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• 101. [Article] Effect of Solute and Temperature on Osmotic Tolerance _Final.pdf

  Citation × Citation Citation Abstract Copy Title: Effect of Solute and Temperature on Osmotic Tolerance _Final.pdf Author: Huang, Kenneth Title: Effect of Solute and Temperature on Osmotic Tolerance _Final.pdf Author: Huang, Kenneth Close

• 102. [Article] Comparison between thermophilic and mesophilic aerobic biological treatment of a synthetic organic waste

  Temperature is one of the most important factors affecting microbial activity and consequently is of great importance in a biological waste treatment system. Extensive research has been carried out to ...

  Citation × Citation Citation Abstract Copy Title: Comparison between thermophilic and mesophilic aerobic biological treatment of a synthetic organic waste Author: Streebin, Leale E. Temperature is one of the most important factors affecting microbial activity and consequently is of great importance in a biological waste treatment system. Extensive research has been carried out to determine the effects of temperature on biological reactions in the temperature range of 20° to 35° Centigrade. It is generally agreed that the reaction rate increases by a factor of two to three for each ten degree Centigrade rise in temperature within this range. There has, however, been very little research to determine temperature effects in the range of 35° to 60° Centigrade. Therefore it was deemed necessary to determine the effect of temperature on aerobic biological treatment of an organic waste in the temperature range of 20° to 60° Centigrade. The impetus motivating this research is the need for a treatment process capable of immediate treatment of high temperature wastes such as some canning wastes and pulp and paper wastes, without prior cooling. At present the thermal energy from high temperature wastes is dissipated by use of cooling towers or other cooling devices. If it is possible to use the thermal energy to increase the decomposition rates in a treatment process, then of course it is desirable to do so. To evaluate the feasibility of high temperature treatment it was imperative to devise a method or means by which to compare the organic removal rates and treatment efficiencies at the various temperatures. To make these comparisons it was necessary to determine at the various temperatures the maximum rate of oxygen demand, the efficiency of organic removal, the quantity and forms of nitrogen being discharged in the effluent, the net solids produced, and the settling characteristics of the sludge. To compare treatment efficiencies at the various temperatures the following tests and determinations were performed: 1. Suspended Solids 2. Chemical Oxygen Demand 3. Nitrogen 4. Oxygen Upptake 5. Type of Growth 6. Settling Characteristics The conclusions drawn from these tests results are as follows: 1. The biochemical activity rate as measured by oxygen uptake increased from 20° to 45°C. The rate dropped rapidly as the temperature was increased above 45°C. 2. The COD removal efficiency was above 90% for the entire range. 3. The net solids production decreased as temperature was increased from 25° to 50°C. 4. Clarification is difficult at temperatures above 35°C. 5. Nitrification does not take place above 40°C. 6. The purification rate can be increased tremendously by increasing the temperature from 20°C to 45°C. 7. High temperature treatment appears to be readily adaptable to dispersed growth systems. However, thermophilic treatment does not appear to be applicable to treatment systems which require solids removal because of the poor settling characteristics. Title: Comparison between thermophilic and mesophilic aerobic biological treatment of a synthetic organic waste Author: Streebin, Leale E. Temperature is one of the most important factors affecting microbial activity and consequently is of great importance in a biological waste treatment system. Extensive research has been carried out to determine the effects of temperature on biological reactions in the temperature range of 20° to 35° Centigrade. It is generally agreed that the reaction rate increases by a factor of two to three for each ten degree Centigrade rise in temperature within this range. There has, however, been very little research to determine temperature effects in the range of 35° to 60° Centigrade. Therefore it was deemed necessary to determine the effect of temperature on aerobic biological treatment of an organic waste in the temperature range of 20° to 60° Centigrade. The impetus motivating this research is the need for a treatment process capable of immediate treatment of high temperature wastes such as some canning wastes and pulp and paper wastes, without prior cooling. At present the thermal energy from high temperature wastes is dissipated by use of cooling towers or other cooling devices. If it is possible to use the thermal energy to increase the decomposition rates in a treatment process, then of course it is desirable to do so. To evaluate the feasibility of high temperature treatment it was imperative to devise a method or means by which to compare the organic removal rates and treatment efficiencies at the various temperatures. To make these comparisons it was necessary to determine at the various temperatures the maximum rate of oxygen demand, the efficiency of organic removal, the quantity and forms of nitrogen being discharged in the effluent, the net solids produced, and the settling characteristics of the sludge. To compare treatment efficiencies at the various temperatures the following tests and determinations were performed: 1. Suspended Solids 2. Chemical Oxygen Demand 3. Nitrogen 4. Oxygen Upptake 5. Type of Growth 6. Settling Characteristics The conclusions drawn from these tests results are as follows: 1. The biochemical activity rate as measured by oxygen uptake increased from 20° to 45°C. The rate dropped rapidly as the temperature was increased above 45°C. 2. The COD removal efficiency was above 90% for the entire range. 3. The net solids production decreased as temperature was increased from 25° to 50°C. 4. Clarification is difficult at temperatures above 35°C. 5. Nitrification does not take place above 40°C. 6. The purification rate can be increased tremendously by increasing the temperature from 20°C to 45°C. 7. High temperature treatment appears to be readily adaptable to dispersed growth systems. However, thermophilic treatment does not appear to be applicable to treatment systems which require solids removal because of the poor settling characteristics. Close

• 103. [Article] The Effect of HSA and Hematocrit on the Cake Collapse Temperature of Lyophilized Red Blood Cells

  Freeze-drying, or lyophilization, has shown great promise in addressing many of the logistical challenges of storing and preserving red blood cells (RBCs). A crucial part of any future RBC lyophilization ...

  Citation × Citation Citation Abstract Copy Title: The Effect of HSA and Hematocrit on the Cake Collapse Temperature of Lyophilized Red Blood Cells Author: Runyon, Daniel E. Freeze-drying, or lyophilization, has shown great promise in addressing many of the logistical challenges of storing and preserving red blood cells (RBCs). A crucial part of any future RBC lyophilization protocol is the primary drying temperature, which affects the sample drying rate and the dried cake’s ability to form a stable glassy solid which is critical to long-term RBC survival. The optimal temperature for primary drying is just below the temperature at which the porous structure of the cake begins to collapse, known as the cake collapse temperature. Therefore, this study utilized Freeze-Dry Microscopy of intracellular Trehalose-loaded RBC suspended in a buffer solution containing Human Serum Albumin (HSA) to determine the effect of both RBC and HSA concentration on the measured cake collapse temperature. It was found that increasing RBC concentration from 5% to 20% hematocrit raised the cake collapse temperature from -36.4°C ± 0.3 to -34.8°C ± 0.2, while increasing HSA concentration from 0 to 5% (w/v) raised the cake collapse temperature from -34.8°C ± 0.2 to -20.4°C ± 1.5. This data provides a basis for future study of the relationship between cake collapse and overall cell survival, with the object of building a clinically-viable RBC lyophilization protocol. Title: The Effect of HSA and Hematocrit on the Cake Collapse Temperature of Lyophilized Red Blood Cells Author: Runyon, Daniel E. Freeze-drying, or lyophilization, has shown great promise in addressing many of the logistical challenges of storing and preserving red blood cells (RBCs). A crucial part of any future RBC lyophilization protocol is the primary drying temperature, which affects the sample drying rate and the dried cake’s ability to form a stable glassy solid which is critical to long-term RBC survival. The optimal temperature for primary drying is just below the temperature at which the porous structure of the cake begins to collapse, known as the cake collapse temperature. Therefore, this study utilized Freeze-Dry Microscopy of intracellular Trehalose-loaded RBC suspended in a buffer solution containing Human Serum Albumin (HSA) to determine the effect of both RBC and HSA concentration on the measured cake collapse temperature. It was found that increasing RBC concentration from 5% to 20% hematocrit raised the cake collapse temperature from -36.4°C ± 0.3 to -34.8°C ± 0.2, while increasing HSA concentration from 0 to 5% (w/v) raised the cake collapse temperature from -34.8°C ± 0.2 to -20.4°C ± 1.5. This data provides a basis for future study of the relationship between cake collapse and overall cell survival, with the object of building a clinically-viable RBC lyophilization protocol. Close

• 104. [Article] Mapping the thermal climate of the H. J. Andrews Experimental Forest, Oregon

  The H. J. Andrews Experimental Forest in the Cascades of central Oregon provides a unique opportunity to study spatial climate patterns on a relatively small scale. Historical records at the 64 square-kilometer ...

  Citation × Citation Citation Abstract Copy Title: Mapping the thermal climate of the H. J. Andrews Experimental Forest, Oregon Author: Smith, Jonathan W. The H. J. Andrews Experimental Forest in the Cascades of central Oregon provides a unique opportunity to study spatial climate patterns on a relatively small scale. Historical records at the 64 square-kilometer site provide a spatiallydense 30-year dataset. Thermal regimes at the H. J. Andrews are generally known but the effects of its complex topography and canopy cover on temperatures have been poorly understood. In this study, 1971-2000 mean monthly maximum and minimum temperature maps of the H. J. Andrews were created over a 50- meter grid, accounting for several environmental factors affecting microclimates in forested, mountainous terrain. The effects of elevation, forest canopy, cloudiness, and topographic shading on radiation regimes were assumed to be the primary factors and the datasets were adjusted to account for them. Specifically, it was assumed that maximum temperatures were affected by shortwave daytime radiation regimes, and minimum temperatures were affected by surface longwave radiation emission at night. The Image-Processing Workbench (IPW) was used to estimate incoming shortwave solar radiation at all climate station sites, taking into account elevation, cloudiness and topographic shading. Using IPW, fisheye photographs, and the HemiView program, proportions of solar radiation and sky view factors blocked by the tree canopy were calculated at each site, and accounted for when calculating daily shortwave radiation values for each month. Sky view factors were calculated at each site accounting for canopy and surrounding topography. Specific site pairs were then analyzed by plotting observed monthly temperature differences against simulated radiation and sky view factors and computing monthly regression functions. Monthly maximum temperature/shortwave radiation regression functions were used to adjust maximum temperatures onto 'open, flat' terrain, (leaving only elevation effects on temperatures), and monthly minimum temperature/sky view factor regression functions were used to adjust minimum temperatures. Temperatures were spatially interpolated over the H. J. Andrews using the Parameter-elevation Regressions on Independent Slopes Model (PRISM) program, which calculates spatially-varying temperature/elevation gradients. Topographic effects of shortwave radiation and sky view factors were reintroduced to the PRISM temperature grids using the appropriate regression functions. To make the resulting maps as useful and applicable as possible for future research, temperatures were modeled to simulate open siting conditions common in NWS station networks. Overall, temperatures were most sensitive to elevation and topographic position. Maximum temperature was sensitive to variations in shortwave radiation, especially in winter when solar radiation loads were small. Minimum temperature was sensitive to variations in sky view factors, particularly during clear summer months. Factors not accounted for in the project include small-scale effects of cold-air drainage, forest edge effects, topographic scale effects, and stream effects. These and other issues are summarized in a set of recommendations for future climate mapping research in the H. J. Andrews. Title: Mapping the thermal climate of the H. J. Andrews Experimental Forest, Oregon Author: Smith, Jonathan W. The H. J. Andrews Experimental Forest in the Cascades of central Oregon provides a unique opportunity to study spatial climate patterns on a relatively small scale. Historical records at the 64 square-kilometer site provide a spatiallydense 30-year dataset. Thermal regimes at the H. J. Andrews are generally known but the effects of its complex topography and canopy cover on temperatures have been poorly understood. In this study, 1971-2000 mean monthly maximum and minimum temperature maps of the H. J. Andrews were created over a 50- meter grid, accounting for several environmental factors affecting microclimates in forested, mountainous terrain. The effects of elevation, forest canopy, cloudiness, and topographic shading on radiation regimes were assumed to be the primary factors and the datasets were adjusted to account for them. Specifically, it was assumed that maximum temperatures were affected by shortwave daytime radiation regimes, and minimum temperatures were affected by surface longwave radiation emission at night. The Image-Processing Workbench (IPW) was used to estimate incoming shortwave solar radiation at all climate station sites, taking into account elevation, cloudiness and topographic shading. Using IPW, fisheye photographs, and the HemiView program, proportions of solar radiation and sky view factors blocked by the tree canopy were calculated at each site, and accounted for when calculating daily shortwave radiation values for each month. Sky view factors were calculated at each site accounting for canopy and surrounding topography. Specific site pairs were then analyzed by plotting observed monthly temperature differences against simulated radiation and sky view factors and computing monthly regression functions. Monthly maximum temperature/shortwave radiation regression functions were used to adjust maximum temperatures onto 'open, flat' terrain, (leaving only elevation effects on temperatures), and monthly minimum temperature/sky view factor regression functions were used to adjust minimum temperatures. Temperatures were spatially interpolated over the H. J. Andrews using the Parameter-elevation Regressions on Independent Slopes Model (PRISM) program, which calculates spatially-varying temperature/elevation gradients. Topographic effects of shortwave radiation and sky view factors were reintroduced to the PRISM temperature grids using the appropriate regression functions. To make the resulting maps as useful and applicable as possible for future research, temperatures were modeled to simulate open siting conditions common in NWS station networks. Overall, temperatures were most sensitive to elevation and topographic position. Maximum temperature was sensitive to variations in shortwave radiation, especially in winter when solar radiation loads were small. Minimum temperature was sensitive to variations in sky view factors, particularly during clear summer months. Factors not accounted for in the project include small-scale effects of cold-air drainage, forest edge effects, topographic scale effects, and stream effects. These and other issues are summarized in a set of recommendations for future climate mapping research in the H. J. Andrews. Close

• 105. [Article] Studies on the effect of moderate temperature on Vibrio marinus

  Washed cells of Vibrio marinus MP-1 grown at 15 C (organism's optimum growth temperature) were employed in this study. These cells were exposed to heat at and above their maximal growth temperature (20 ...

  Citation × Citation Citation Abstract Copy Title: Studies on the effect of moderate temperature on Vibrio marinus Author: Robison, Sarah May Washed cells of Vibrio marinus MP-1 grown at 15 C (organism's optimum growth temperature) were employed in this study. These cells were exposed to heat at and above their maximal growth temperature (20 C) for one hour and tested manometrically at 15 C for their ability to take up oxygen. Endogenous activity, as evidenced by oxygen uptake, decreased with increased temperatures of exposure and was destroyed at 30 C. The same pattern of oxygen uptake was noted when glucose was employed as the substrate. Oxygen uptake decreased with increasing exposure periods at temperatures above the maximum growth temperature. Endogenous oxygen uptake was negligible after exposure at 29.2 C for 50 minutes. The supernatants, which resulted from suspensions of cells exposed to 15 to 35 C, contained 260-280 mμ absorbing material. This increased with increased temperature as well as increased time of exposure. The most radical changes occurred above 28 C. Supernatants were further analyzed for Kjeldahl nitrogen, orcinol reacting material and diphenylamine reacting material. The latter are indicative of ribonucleic and deoxyribonucleic acid respectively. The data indicates that moderate temperatures from 20 to 30 C are sufficient to inactivate the metabolic systems involved in oxygen uptake both endogenously and in the presence of glucose. Also, cellular composition and permeability are affected, as evidenced by the leakage of 260-280 mμ material. Title: Studies on the effect of moderate temperature on Vibrio marinus Author: Robison, Sarah May Washed cells of Vibrio marinus MP-1 grown at 15 C (organism's optimum growth temperature) were employed in this study. These cells were exposed to heat at and above their maximal growth temperature (20 C) for one hour and tested manometrically at 15 C for their ability to take up oxygen. Endogenous activity, as evidenced by oxygen uptake, decreased with increased temperatures of exposure and was destroyed at 30 C. The same pattern of oxygen uptake was noted when glucose was employed as the substrate. Oxygen uptake decreased with increasing exposure periods at temperatures above the maximum growth temperature. Endogenous oxygen uptake was negligible after exposure at 29.2 C for 50 minutes. The supernatants, which resulted from suspensions of cells exposed to 15 to 35 C, contained 260-280 mμ absorbing material. This increased with increased temperature as well as increased time of exposure. The most radical changes occurred above 28 C. Supernatants were further analyzed for Kjeldahl nitrogen, orcinol reacting material and diphenylamine reacting material. The latter are indicative of ribonucleic and deoxyribonucleic acid respectively. The data indicates that moderate temperatures from 20 to 30 C are sufficient to inactivate the metabolic systems involved in oxygen uptake both endogenously and in the presence of glucose. Also, cellular composition and permeability are affected, as evidenced by the leakage of 260-280 mμ material. Close

• 106. [Article] HuffJulieA2009.pdf

  Citation × Citation Citation Abstract Copy Title: HuffJulieA2009.pdf Author: Huff, Julie A. Title: HuffJulieA2009.pdf Author: Huff, Julie A. Close

• 107. [Article] Simulation of postdiapause development of the western cherry fruit fly, Rhagoletis indifferens Curran, and its application to predicting the time of adult emergence

  Air temperatures and soil temperatures at the surface, two inches, and four inches under a grass cover were recorded over a 93 day period. These data were used along with other temperature data from bare ...

  Citation × Citation Citation Abstract Copy Title: Simulation of postdiapause development of the western cherry fruit fly, Rhagoletis indifferens Curran, and its application to predicting the time of adult emergence Author: Stark, Steven Bruce Air temperatures and soil temperatures at the surface, two inches, and four inches under a grass cover were recorded over a 93 day period. These data were used along with other temperature data from bare soil in the construction of three sets of models for the prediction of maximum and minimum daily temperatures at several depths below bare and grass-covered soils. The model set having the most accurate predictions was used in conjunction with models for predicting the temperature-dependent postdiapause development of the western cherry fruit fly, Rhagoletis indifferens Curran. Postdiapause developmental rates of R. indifferens pupae collected from Albany, Oregon and Zillah, Washington were determined under constant temperature conditions. Mean times until adult emergence from Albany puparia and Zillah puparia exposed to the same constant temperature were found to be significantly different (α = .01) for all temperatures tested (15.5°C., 19.5°C., and 25.5°C.). Mean times until adult emergence from Zillah puparia held in moist sand at 15.5°C. and in dry sand at 15.5°C. were also found to be significantly different (α = .01). Thus, geographical location and presence or absence of moisture were implicated as factors which may affect the accuracy of the postdiapause development models. Albany puparia were exposed to two alternating temperature regimes to determine if the mean time of adult emergence under alternating temperature conditions can be predicted using constant temperature developmental rate data. The observed mean time of emergence from puparia exposed to a regime with extreme temperature changes was found to be significantly different (α = .01) from the expected mean time of emergence. No significant difference (α = .01) was found between observed and expected mean times of emergence from puparia exposed to the other regime, in which temperatures more closely simulated those found in the field. Albany puparia from which no emergence occurred were dissected to determine the developmental stages of their contents. These data were used in an attempt to determine the upper and lower temperature thresholds for postdiapause development. Thirty degrees C. was established as the upper threshold. A lower threshold was not clearly shown, although the data suggest that it is greater than 6°C. Four models of the postdiapause development of R. indifferens were constructed and evaluated for accuracy of predictions of the times of several levels of adult emergence from an experimental abandoned orchard in Albany, Oregon. The models predict temperature-dependent postdiapause development based on soil temperatures predicted by the soil temperature model set. Three of the models predict postdiapause development on the basis of day-degree relationships. The predictions of the fourth model are based upon a nonlinear temperature-dependent developmental rate function. This model predicted the times of adult emergence with mean errors of ca. two days per year. Thus, it was found to likely be more accurate than other models reported here and elsewhere for the prediction of the times of various levels of emergence of the adult western cherry fruit fly. Title: Simulation of postdiapause development of the western cherry fruit fly, Rhagoletis indifferens Curran, and its application to predicting the time of adult emergence Author: Stark, Steven Bruce Air temperatures and soil temperatures at the surface, two inches, and four inches under a grass cover were recorded over a 93 day period. These data were used along with other temperature data from bare soil in the construction of three sets of models for the prediction of maximum and minimum daily temperatures at several depths below bare and grass-covered soils. The model set having the most accurate predictions was used in conjunction with models for predicting the temperature-dependent postdiapause development of the western cherry fruit fly, Rhagoletis indifferens Curran. Postdiapause developmental rates of R. indifferens pupae collected from Albany, Oregon and Zillah, Washington were determined under constant temperature conditions. Mean times until adult emergence from Albany puparia and Zillah puparia exposed to the same constant temperature were found to be significantly different (α = .01) for all temperatures tested (15.5°C., 19.5°C., and 25.5°C.). Mean times until adult emergence from Zillah puparia held in moist sand at 15.5°C. and in dry sand at 15.5°C. were also found to be significantly different (α = .01). Thus, geographical location and presence or absence of moisture were implicated as factors which may affect the accuracy of the postdiapause development models. Albany puparia were exposed to two alternating temperature regimes to determine if the mean time of adult emergence under alternating temperature conditions can be predicted using constant temperature developmental rate data. The observed mean time of emergence from puparia exposed to a regime with extreme temperature changes was found to be significantly different (α = .01) from the expected mean time of emergence. No significant difference (α = .01) was found between observed and expected mean times of emergence from puparia exposed to the other regime, in which temperatures more closely simulated those found in the field. Albany puparia from which no emergence occurred were dissected to determine the developmental stages of their contents. These data were used in an attempt to determine the upper and lower temperature thresholds for postdiapause development. Thirty degrees C. was established as the upper threshold. A lower threshold was not clearly shown, although the data suggest that it is greater than 6°C. Four models of the postdiapause development of R. indifferens were constructed and evaluated for accuracy of predictions of the times of several levels of adult emergence from an experimental abandoned orchard in Albany, Oregon. The models predict temperature-dependent postdiapause development based on soil temperatures predicted by the soil temperature model set. Three of the models predict postdiapause development on the basis of day-degree relationships. The predictions of the fourth model are based upon a nonlinear temperature-dependent developmental rate function. This model predicted the times of adult emergence with mean errors of ca. two days per year. Thus, it was found to likely be more accurate than other models reported here and elsewhere for the prediction of the times of various levels of emergence of the adult western cherry fruit fly. Close

• 108. [Article] Surface temperature lapse rates over complex terrain: Lessons from the Cascade Mountains

  The typically sparse distribution of weather stations in mountainous terrain inadequately resolves temperature variability. Accordingly, high‐resolution gridding of climate data (for applications such ...

  Citation × Citation Citation Abstract Copy Title: Surface temperature lapse rates over complex terrain: Lessons from the Cascade Mountains Author: Mote, Philip W., Lundquist, Jessica D., Minder, Justin R. The typically sparse distribution of weather stations in mountainous terrain inadequately resolves temperature variability. Accordingly, high‐resolution gridding of climate data (for applications such as hydrological modeling) often relies on assumptions such as a constant surface temperature lapse rate (i.e., decrease of surface temperature with altitude) of 6.5°C km⁻¹. Using an example of the Cascade Mountains, we describe the temporal and spatial variability of the surface temperature lapse rate, combining data from: (1) COOP stations, (2) nearby radiosonde launches, (3) a temporary dense network of sensors, (4) forecasts from the MM5 regional model, and (5) PRISM geo‐statistical analyses. On the windward side of the range, the various data sources reveal annual mean lapse rates of 3.9–5.2°C km⁻¹, substantially smaller than the often‐assumed 6.5°C km⁻¹. The data sets show similar seasonal and diurnal variability, with lapse rates smallest (2.5–3.5°C km⁻¹) in late‐summer minimum temperatures, and largest (6.5–7.5°C km⁻¹) in spring maximum temperatures. Geographic (windward versus lee side) differences in lapse rates are found to be substantial. Using a simple runoff model, we show the appreciable implications of these results for hydrological modeling. Title: Surface temperature lapse rates over complex terrain: Lessons from the Cascade Mountains Author: Mote, Philip W., Lundquist, Jessica D., Minder, Justin R. The typically sparse distribution of weather stations in mountainous terrain inadequately resolves temperature variability. Accordingly, high‐resolution gridding of climate data (for applications such as hydrological modeling) often relies on assumptions such as a constant surface temperature lapse rate (i.e., decrease of surface temperature with altitude) of 6.5°C km⁻¹. Using an example of the Cascade Mountains, we describe the temporal and spatial variability of the surface temperature lapse rate, combining data from: (1) COOP stations, (2) nearby radiosonde launches, (3) a temporary dense network of sensors, (4) forecasts from the MM5 regional model, and (5) PRISM geo‐statistical analyses. On the windward side of the range, the various data sources reveal annual mean lapse rates of 3.9–5.2°C km⁻¹, substantially smaller than the often‐assumed 6.5°C km⁻¹. The data sets show similar seasonal and diurnal variability, with lapse rates smallest (2.5–3.5°C km⁻¹) in late‐summer minimum temperatures, and largest (6.5–7.5°C km⁻¹) in spring maximum temperatures. Geographic (windward versus lee side) differences in lapse rates are found to be substantial. Using a simple runoff model, we show the appreciable implications of these results for hydrological modeling. Close

• 109. [Article] Studies involving substrate binding, uptake, and respiration near the minimum growth temperature of Escherichia coli

  Escherichia coli K12, UC41 (an auxotroph) and UC175 (a wild type) were used to determine possible relationships between binding, uptake, and respiration and minimum growth temperature. Both E. coli strains ...

  Citation × Citation Citation Abstract Copy Title: Studies involving substrate binding, uptake, and respiration near the minimum growth temperature of Escherichia coli Author: Goodrich, Thomas Dale Escherichia coli K12, UC41 (an auxotroph) and UC175 (a wild type) were used to determine possible relationships between binding, uptake, and respiration and minimum growth temperature. Both E. coli strains had a minimum growth temperature of 8.0 C in glucose minimal medium when cells were previously grown at 15 C. UC41 showed a greater uptake rate of the amino acids than did UC175. A nearly constant uptake rate of L-methionine by UC41 below the minimum growth temperature was seen regardless of the wash treatment used during filtration. At and above the minimum growth temperature, uptake increased with increasing temperature indicating a direct relationship between binding and uptake and the minimum growth temperature. Cells of UC41 which were osmotically shocked to remove the histidine-binding protein were unable to resynthesize new binding protein below 8 C. The auxotroph also had a smaller uptake constant for arginine at and above the minimum growth temperature than below. Title: Studies involving substrate binding, uptake, and respiration near the minimum growth temperature of Escherichia coli Author: Goodrich, Thomas Dale Escherichia coli K12, UC41 (an auxotroph) and UC175 (a wild type) were used to determine possible relationships between binding, uptake, and respiration and minimum growth temperature. Both E. coli strains had a minimum growth temperature of 8.0 C in glucose minimal medium when cells were previously grown at 15 C. UC41 showed a greater uptake rate of the amino acids than did UC175. A nearly constant uptake rate of L-methionine by UC41 below the minimum growth temperature was seen regardless of the wash treatment used during filtration. At and above the minimum growth temperature, uptake increased with increasing temperature indicating a direct relationship between binding and uptake and the minimum growth temperature. Cells of UC41 which were osmotically shocked to remove the histidine-binding protein were unable to resynthesize new binding protein below 8 C. The auxotroph also had a smaller uptake constant for arginine at and above the minimum growth temperature than below. Close

• 110. [Article] Topographic heterogeneity and the spatial pattern of air temperature in a mountain landscape

  The objective of this study was to compile, validate, and map minimum and maximum mean monthly temperature and temperature ranges for periods of 10 to 14 months between July 2009 and June 2012, measured ...

  Citation × Citation Citation Abstract Copy Title: Topographic heterogeneity and the spatial pattern of air temperature in a mountain landscape Author: Wilson, Brian Marc The objective of this study was to compile, validate, and map minimum and maximum mean monthly temperature and temperature ranges for periods of 10 to 14 months between July 2009 and June 2012, measured using 16 to 182 sensors distributed over the HJ Andrews Forest, a mountain landscape of 64 km². Maps were created using inverse distance weighting (IDW) as an extrapolation method in Arc GIS 10.1. We found that temperature was dominated by lapse-rate, topographic shading, and cold air pooling effects, depending on the time of year. Both minimum and maximum monthly temperature in spring (some Mar, April, May, and even June) and fall (Oct, Nov) tends to be lapse-rate dominated. Late summer (Aug, Sep, Oct) maximum temperature tends to be dominated by topographic shading, despite interannual variation in precipitation. Cold air pooling appeared in July, August, and September minimum temperature, but in maximum temperature only for a dry December (2011). Additional sensors (from 16 to 40 or even 56) increase the ability to identify topographic shading patterns and the associated heterogeneity in temperature, with weak indications of cold air pooling. Even more sensors (from 40/56 to 166/182) increase the ability to identify very small scale variability, including cool air pooling in the main-stem valley of the Andrews Forest. For a given month, temperature spatial patterns were fairly consistent from one year to another. For a given month, temperature values between years vary with interannual variation in precipitation. Some sites in the Andrews Forest have a very large diurnal temperature range (mean monthly min to mean monthly max) while other sites have very small ranges. Sites close to each other may have very different mean monthly temperature, due to the effect of topography. Sites with the largest temperature ranges were on the south-facing slopes of Carpenter Mountain, and those with the smallest ranges were along the north-facing slope of the south side of Andrews Forest (Lookout Ridge) and northwest of the upper end of Lookout Creek. North-facing slopes on Lookout Mountain and Roswell Ridge may also have very small temperature ranges, but these areas were not instrumented. Sites with small temperature ranges may serve as refugia for organisms in response to climate change. For mountain environments subjected to climate change, these findings imply that different parts of the landscape experience climate change differently. There may be "refugia" from climate change in mountain landscapes, defined as locations with small diurnal and seasonal temperature ranges. Title: Topographic heterogeneity and the spatial pattern of air temperature in a mountain landscape Author: Wilson, Brian Marc The objective of this study was to compile, validate, and map minimum and maximum mean monthly temperature and temperature ranges for periods of 10 to 14 months between July 2009 and June 2012, measured using 16 to 182 sensors distributed over the HJ Andrews Forest, a mountain landscape of 64 km². Maps were created using inverse distance weighting (IDW) as an extrapolation method in Arc GIS 10.1. We found that temperature was dominated by lapse-rate, topographic shading, and cold air pooling effects, depending on the time of year. Both minimum and maximum monthly temperature in spring (some Mar, April, May, and even June) and fall (Oct, Nov) tends to be lapse-rate dominated. Late summer (Aug, Sep, Oct) maximum temperature tends to be dominated by topographic shading, despite interannual variation in precipitation. Cold air pooling appeared in July, August, and September minimum temperature, but in maximum temperature only for a dry December (2011). Additional sensors (from 16 to 40 or even 56) increase the ability to identify topographic shading patterns and the associated heterogeneity in temperature, with weak indications of cold air pooling. Even more sensors (from 40/56 to 166/182) increase the ability to identify very small scale variability, including cool air pooling in the main-stem valley of the Andrews Forest. For a given month, temperature spatial patterns were fairly consistent from one year to another. For a given month, temperature values between years vary with interannual variation in precipitation. Some sites in the Andrews Forest have a very large diurnal temperature range (mean monthly min to mean monthly max) while other sites have very small ranges. Sites close to each other may have very different mean monthly temperature, due to the effect of topography. Sites with the largest temperature ranges were on the south-facing slopes of Carpenter Mountain, and those with the smallest ranges were along the north-facing slope of the south side of Andrews Forest (Lookout Ridge) and northwest of the upper end of Lookout Creek. North-facing slopes on Lookout Mountain and Roswell Ridge may also have very small temperature ranges, but these areas were not instrumented. Sites with small temperature ranges may serve as refugia for organisms in response to climate change. For mountain environments subjected to climate change, these findings imply that different parts of the landscape experience climate change differently. There may be "refugia" from climate change in mountain landscapes, defined as locations with small diurnal and seasonal temperature ranges. Close

• 111. [Article] Spatial and temporal characteristics of surface air temperature for Portland, Oregon

  This study examines the spatial and temporal characteristics of the surface air temperature in Portland, Oregon. Spatial temperature patterns indicate that the dominant control factors on seasonal temperature ...

  Citation × Citation Citation Abstract Copy Title: Spatial and temporal characteristics of surface air temperature for Portland, Oregon Author: Yang, Li-min Year: 1987 This study examines the spatial and temporal characteristics of the surface air temperature in Portland, Oregon. Spatial temperature patterns indicate that the dominant control factors on seasonal temperature distribution are local topography, elevation, and urban-rural differences in surface structure. A heat island exists in the Portland area; the intensity of the heat island rang€s from 4° to 10° F, and varies throughout the year. The strongest heat island is found in the July minimum temperature. Temperature distribution in Portland and the adjacent area is affected by winds and rainy conditions, but less influenced under overcast skies. The long-term temperature over the last century shows that Portland's mean annual temperature trends are 0.057° F/yr and 0.052° F/yr in the two warming periods 1900-1940 and 1961-1984, respectively, and these warming trends are largely due to warming in spring and early summer as well as in winter months except January. Comparisons between Portland and other local non-urban climatic stations show a general warming trend in Portland since the end of the last century, which is 0.028° F/yr in the mean annual temperature, and 0.017° F/yr in maximum temperature after the regional trends are removed. Monthly mean temperature in July and January demonstrate a warming by 0.023° F/yr and 0.015° F/yr at Portland, respectively. All these warming trends are due mainly to the impact of urbanization. It is found that the cooling effect on the northern Willamette Valley due to the presence of the Columbia Gorge is most noticeable in the daytime and in January. Title: Spatial and temporal characteristics of surface air temperature for Portland, Oregon Author: Yang, Li-min Year: 1987 This study examines the spatial and temporal characteristics of the surface air temperature in Portland, Oregon. Spatial temperature patterns indicate that the dominant control factors on seasonal temperature distribution are local topography, elevation, and urban-rural differences in surface structure. A heat island exists in the Portland area; the intensity of the heat island rang€s from 4° to 10° F, and varies throughout the year. The strongest heat island is found in the July minimum temperature. Temperature distribution in Portland and the adjacent area is affected by winds and rainy conditions, but less influenced under overcast skies. The long-term temperature over the last century shows that Portland's mean annual temperature trends are 0.057° F/yr and 0.052° F/yr in the two warming periods 1900-1940 and 1961-1984, respectively, and these warming trends are largely due to warming in spring and early summer as well as in winter months except January. Comparisons between Portland and other local non-urban climatic stations show a general warming trend in Portland since the end of the last century, which is 0.028° F/yr in the mean annual temperature, and 0.017° F/yr in maximum temperature after the regional trends are removed. Monthly mean temperature in July and January demonstrate a warming by 0.023° F/yr and 0.015° F/yr at Portland, respectively. All these warming trends are due mainly to the impact of urbanization. It is found that the cooling effect on the northern Willamette Valley due to the presence of the Columbia Gorge is most noticeable in the daytime and in January. Close

• 112. [Article] Impact of Soil Moisture–Atmosphere Interactions on Surface Temperature Distribution

  Understanding how different physical processes can shape the probability distribution function (PDF) of surface temperature, in particular the tails of the distribution, is essential for the attribution ...

  Citation × Citation Citation Abstract Copy Title: Impact of Soil Moisture–Atmosphere Interactions on Surface Temperature Distribution Author: Berg, Alexis, Lintner, Benjamin R., Findell, Kirsten L., Malyshev, Sergey, Loikith, Paul C., Gentine, Pierre Year: 2014 Understanding how different physical processes can shape the probability distribution function (PDF) of surface temperature, in particular the tails of the distribution, is essential for the attribution and projection of future extreme temperature events. In this study, the contribution of soil moisture–atmosphere interactions to surface temperature PDFs is investigated. Soil moisture represents a key variable in the coupling of the land and atmosphere, since it controls the partitioning of available energy between sensible and latent heat flux at the surface. Consequently, soil moisture variability driven by the atmosphere may feed back onto the near-surface climate—in particular, temperature. In this study, two simulations of the current-generation Geophysical Fluid Dynamics Laboratory (GFDL) Earth System Model, with and without interactive soil moisture, are analyzed in order to assess how soil moisture dynamics impact the simulated climate. Comparison of these simulations shows that soil moisture dynamics enhance both temperature mean and variance over regional ‘‘hotspots’’ of land–atmosphere coupling.Moreover, higher-order distribution moments, such as skewness and kurtosis, are also significantly impacted, suggesting an asymmetric impact on the positive and negative extremes of the temperature PDF. Such changes are interpreted in the context of altered distributions of the surface turbulent and radiative fluxes. That the moments of the temperature distribution may respond differentially to soil moisture dynamics underscores the importance of analyzing moments beyond the mean and variance to characterize fully the interplay of soil moisture and near-surface temperature. In addition, it is shown that soil moisture dynamics impacts daily temperature variability at different time scales over different regions in the model. Title: Impact of Soil Moisture–Atmosphere Interactions on Surface Temperature Distribution Author: Berg, Alexis, Lintner, Benjamin R., Findell, Kirsten L., Malyshev, Sergey, Loikith, Paul C., Gentine, Pierre Year: 2014 Understanding how different physical processes can shape the probability distribution function (PDF) of surface temperature, in particular the tails of the distribution, is essential for the attribution and projection of future extreme temperature events. In this study, the contribution of soil moisture–atmosphere interactions to surface temperature PDFs is investigated. Soil moisture represents a key variable in the coupling of the land and atmosphere, since it controls the partitioning of available energy between sensible and latent heat flux at the surface. Consequently, soil moisture variability driven by the atmosphere may feed back onto the near-surface climate—in particular, temperature. In this study, two simulations of the current-generation Geophysical Fluid Dynamics Laboratory (GFDL) Earth System Model, with and without interactive soil moisture, are analyzed in order to assess how soil moisture dynamics impact the simulated climate. Comparison of these simulations shows that soil moisture dynamics enhance both temperature mean and variance over regional ‘‘hotspots’’ of land–atmosphere coupling.Moreover, higher-order distribution moments, such as skewness and kurtosis, are also significantly impacted, suggesting an asymmetric impact on the positive and negative extremes of the temperature PDF. Such changes are interpreted in the context of altered distributions of the surface turbulent and radiative fluxes. That the moments of the temperature distribution may respond differentially to soil moisture dynamics underscores the importance of analyzing moments beyond the mean and variance to characterize fully the interplay of soil moisture and near-surface temperature. In addition, it is shown that soil moisture dynamics impacts daily temperature variability at different time scales over different regions in the model. Close

• 113. [Article] Optimization of single- and double-flash cycles and space heating systems in geothermal engineering

  Two different problems of optimization in the utilization of geothermal energy are presented: First, the thermodynamic optimization for a geothermal power plant using a single- or double-flash process ...

  Citation × Citation Citation Abstract Copy Title: Optimization of single- and double-flash cycles and space heating systems in geothermal engineering Author: Hassoun, Talal Hussein Year: 1974 Two different problems of optimization in the utilization of geothermal energy are presented: First, the thermodynamic optimization for a geothermal power plant using a single- or double-flash process is considered; in this analysis, the optimum flash temperature giving the maximum power output is determined. Second, an economic optimization for space heating systems using geothermal energy is developed to obtain operating conditions for which the total (capital and operating) cost is a minimum. Both graphical and analytical methods are used in the thermodynamic optimization to determine the optimum flash temperature. The graphical method is based on thermodynamic data provided by an i-s (enthalpy-entropy) diagram for water and steam, in the analytical method, first and second order approximations (first and second degree polynomial approximations), are used for the functions which express enthalpy differences in terms of flash temperature. Numerical results are provided by computer programs developed for the analytical method. These results cover the temperature range normally encountered in practice. In the case of the single-flash cycle, results from both the graphical and analytical method using the first order approximation indicate the same optimum flash temperature; however, the correction factor resulting from the second order approximation improves the value of the temperature by a correction of about -2 ° C. Optimum flash temperatures for the double-flash cycle are similarly determined using the analytical method with a first order approximation. In the economic optimization of space heating systems, the analysis is made on the basis of the annual total cost per unit area of wall surface. It takes into account the cost of the geothermal fluid, cost of wall insulation, and heat exchanger cost. For a specific case where the inlet temperature to the heat exchanger is at 100° C and the outlet temperature at 28° C, the minimum annual cost to maintain a space at 20°C with an outside temperature of -l0°C is given at $0.0257 per square meter of wall area while the optimum thickness for the wall insulation is 0. 126 meter. Additional improvement in the optimization of flash temperature can be made by using a second order approximation method for the double-flash power cycle. Title: Optimization of single- and double-flash cycles and space heating systems in geothermal engineering Author: Hassoun, Talal Hussein Year: 1974 Two different problems of optimization in the utilization of geothermal energy are presented: First, the thermodynamic optimization for a geothermal power plant using a single- or double-flash process is considered; in this analysis, the optimum flash temperature giving the maximum power output is determined. Second, an economic optimization for space heating systems using geothermal energy is developed to obtain operating conditions for which the total (capital and operating) cost is a minimum. Both graphical and analytical methods are used in the thermodynamic optimization to determine the optimum flash temperature. The graphical method is based on thermodynamic data provided by an i-s (enthalpy-entropy) diagram for water and steam, in the analytical method, first and second order approximations (first and second degree polynomial approximations), are used for the functions which express enthalpy differences in terms of flash temperature. Numerical results are provided by computer programs developed for the analytical method. These results cover the temperature range normally encountered in practice. In the case of the single-flash cycle, results from both the graphical and analytical method using the first order approximation indicate the same optimum flash temperature; however, the correction factor resulting from the second order approximation improves the value of the temperature by a correction of about -2 ° C. Optimum flash temperatures for the double-flash cycle are similarly determined using the analytical method with a first order approximation. In the economic optimization of space heating systems, the analysis is made on the basis of the annual total cost per unit area of wall surface. It takes into account the cost of the geothermal fluid, cost of wall insulation, and heat exchanger cost. For a specific case where the inlet temperature to the heat exchanger is at 100° C and the outlet temperature at 28° C, the minimum annual cost to maintain a space at 20°C with an outside temperature of -l0°C is given at $0.0257 per square meter of wall area while the optimum thickness for the wall insulation is 0. 126 meter. Additional improvement in the optimization of flash temperature can be made by using a second order approximation method for the double-flash power cycle. Close

• 114. [Article] Douglas-fir displays a range of growth responses to temperature, water, and Swiss needle cast in western Oregon, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Elsevier and is ...

  Citation × Citation Citation Abstract Copy Title: Douglas-fir displays a range of growth responses to temperature, water, and Swiss needle cast in western Oregon, USA Author: Bollman, Michael, Lee, E. Henry, Carlile, Cailie, Waschmann, Ronald S., Cline, Steve, Tingey, David T., Beedlow, Peter A., Wickham, Charlotte To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Elsevier and is in the public domain. The published article can be found at: http://www.journals.elsevier.com/agricultural-and-forest-meteorology/ Title: Douglas-fir displays a range of growth responses to temperature, water, and Swiss needle cast in western Oregon, USA Author: Bollman, Michael, Lee, E. Henry, Carlile, Cailie, Waschmann, Ronald S., Cline, Steve, Tingey, David T., Beedlow, Peter A., Wickham, Charlotte To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by the Elsevier and is in the public domain. The published article can be found at: http://www.journals.elsevier.com/agricultural-and-forest-meteorology/ Close

• 115. [Article] Predicting the thermo-mechanical behavior of a gypsum-to-wood nailed connection

  With high costs of testing and rating a structural system for fire resistance, the utilization of computer simulations that approximate the integrity of structural subsystems could conceivably reduce development ...

  Citation × Citation Citation Abstract Copy Title: Predicting the thermo-mechanical behavior of a gypsum-to-wood nailed connection Author: Fuller, James J. With high costs of testing and rating a structural system for fire resistance, the utilization of computer simulations that approximate the integrity of structural subsystems could conceivably reduce development costs. Before an analysis of a light-frame wood system can occur, information on the components of the substructure must be known. The purpose of this study was to systematically study the effects of thermal load on the strength and mode of failure in a nailed gypsum-to-wood stud connection. Initially the distribution of temperatures within the connection was sought by using a finite element analysis. The analysis simulated exposure to a standard fire as dictated by the American Society for Testing Materials standard E-119. The thermal properties of the materials involved are documented in the literature. Close agreement was found between analytical results and specimens exposed to standard test conditions. With the temperatures along the connection known, the properties of the three materials at elevated temperatures were needed. For wood and steel, this information has been well documented. The property values for gypsum were accumulated through testing gypsum board in compression at various temperatures. The results showed an increase in compressive strength and stiffness up to 100 C followed by a decrease in strength. These results were combined with the analytically determined temperature distribution to obtain the material properties in the neighborhood of the connection. The overall model was an extension of the yield theory available in the literature. The approach used was to evaluate the connection at set time intervals and calculate the strength of the connection. Each time interval had a different set of material property values for each material in the connection as dictated by the temperature distribution. The mode of failure did not change from that which occurred at room temperature, compression strength of the gypsum being the determining factor. The load at which failure occurred increased in the first five minutes and then sharply decreased. This can now be incorporated into models of wall systems for room temperature to predict behavior of walls during exposure to fire. Title: Predicting the thermo-mechanical behavior of a gypsum-to-wood nailed connection Author: Fuller, James J. With high costs of testing and rating a structural system for fire resistance, the utilization of computer simulations that approximate the integrity of structural subsystems could conceivably reduce development costs. Before an analysis of a light-frame wood system can occur, information on the components of the substructure must be known. The purpose of this study was to systematically study the effects of thermal load on the strength and mode of failure in a nailed gypsum-to-wood stud connection. Initially the distribution of temperatures within the connection was sought by using a finite element analysis. The analysis simulated exposure to a standard fire as dictated by the American Society for Testing Materials standard E-119. The thermal properties of the materials involved are documented in the literature. Close agreement was found between analytical results and specimens exposed to standard test conditions. With the temperatures along the connection known, the properties of the three materials at elevated temperatures were needed. For wood and steel, this information has been well documented. The property values for gypsum were accumulated through testing gypsum board in compression at various temperatures. The results showed an increase in compressive strength and stiffness up to 100 C followed by a decrease in strength. These results were combined with the analytically determined temperature distribution to obtain the material properties in the neighborhood of the connection. The overall model was an extension of the yield theory available in the literature. The approach used was to evaluate the connection at set time intervals and calculate the strength of the connection. Each time interval had a different set of material property values for each material in the connection as dictated by the temperature distribution. The mode of failure did not change from that which occurred at room temperature, compression strength of the gypsum being the determining factor. The load at which failure occurred increased in the first five minutes and then sharply decreased. This can now be incorporated into models of wall systems for room temperature to predict behavior of walls during exposure to fire. Close

• 116. [Article] Distributed fiber-optic temperature sensing for hydrologic systems

  This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://www.agu.org/.

  Citation × Citation Citation Abstract Copy Title: Distributed fiber-optic temperature sensing for hydrologic systems Author: van de Giesen, Nick, Stejskal, Martin, Westhoff, Martijn, Huwald, Hendrik, Mallet, Alfred, Luxemburg, Wim, Zeman, Josef, Parlange, Marc B., Thevenaz, Luc, Selker, John S. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://www.agu.org/. Title: Distributed fiber-optic temperature sensing for hydrologic systems Author: van de Giesen, Nick, Stejskal, Martin, Westhoff, Martijn, Huwald, Hendrik, Mallet, Alfred, Luxemburg, Wim, Zeman, Josef, Parlange, Marc B., Thevenaz, Luc, Selker, John S. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://www.agu.org/. Close

• 117. [Article] Small sample, low-temperature calorimetry

  A calorimeter capable of measuring the heat capacity of 1 mg size samples from 4.2 to greater than 100 K has been designed, constructed, and tested. The sample is bonded to the end of a 0.002 inch diameter, ...

  Citation × Citation Citation Abstract Copy Title: Small sample, low-temperature calorimetry Author: Wolochuk, Lee A calorimeter capable of measuring the heat capacity of 1 mg size samples from 4.2 to greater than 100 K has been designed, constructed, and tested. The sample is bonded to the end of a 0.002 inch diameter, 0.5 cm long chromel-constantan thermocouple (type E) and heated optically with a laser and fiber optic. An advantage of this calorimeter is the low addenda heat capacity of the thermocouple. The thermocouple, which serves not only as the temperature sensor of the sample but also as the thermal link between the sample and a constant temperature reservoir, is anchored to a copper block, which acts as the constant temperature reservoir. Heat capacity is determined from the temperature rate of decay of the sample using a sweep method. The sample is heated to an initial temperature above the block temperature by the laser. The laser is then turned off and the sample temperature is allowed to decay to the block temperature. By measuring the temperature of the sample as a function of time and relating it to the thermal conductivity of the thermocouple in a separate experiment, the sample's heat capacity can be determined. The thermal conductivity of the thermocouple is determined by performing an experiment with a sample of known heat capacity. A design model created with a spreadsheet helped to determine what size thermocouple should be used as well as the best materials and dimensions of the components that make up the calorimeter. The model was also useful in determining the nature of a calorimetry experiment and helped determine how high above the block temperature the sample should be heated, how low the pressure inside the calorimeter should be, and how much time a calorimetry experiment would require. Experiments using copper samples have confirmed the validity of the design. The results of an experiment using a 1.1 mg copper sample agree (within expected uncertainty) with the accepted heat capacity of copper from 7 to 100 K. One factor in the uncertainty is the large heat capacity of the grease (Apiezon N) used to bond the sample to the tip of the thermocouple, especially below 15 K. Title: Small sample, low-temperature calorimetry Author: Wolochuk, Lee A calorimeter capable of measuring the heat capacity of 1 mg size samples from 4.2 to greater than 100 K has been designed, constructed, and tested. The sample is bonded to the end of a 0.002 inch diameter, 0.5 cm long chromel-constantan thermocouple (type E) and heated optically with a laser and fiber optic. An advantage of this calorimeter is the low addenda heat capacity of the thermocouple. The thermocouple, which serves not only as the temperature sensor of the sample but also as the thermal link between the sample and a constant temperature reservoir, is anchored to a copper block, which acts as the constant temperature reservoir. Heat capacity is determined from the temperature rate of decay of the sample using a sweep method. The sample is heated to an initial temperature above the block temperature by the laser. The laser is then turned off and the sample temperature is allowed to decay to the block temperature. By measuring the temperature of the sample as a function of time and relating it to the thermal conductivity of the thermocouple in a separate experiment, the sample's heat capacity can be determined. The thermal conductivity of the thermocouple is determined by performing an experiment with a sample of known heat capacity. A design model created with a spreadsheet helped to determine what size thermocouple should be used as well as the best materials and dimensions of the components that make up the calorimeter. The model was also useful in determining the nature of a calorimetry experiment and helped determine how high above the block temperature the sample should be heated, how low the pressure inside the calorimeter should be, and how much time a calorimetry experiment would require. Experiments using copper samples have confirmed the validity of the design. The results of an experiment using a 1.1 mg copper sample agree (within expected uncertainty) with the accepted heat capacity of copper from 7 to 100 K. One factor in the uncertainty is the large heat capacity of the grease (Apiezon N) used to bond the sample to the tip of the thermocouple, especially below 15 K. Close

• 118. [Article] Does Temperature-Mediated Reproductive Success Drive the Direction of Species Displacement in Two Invasive Species of Leafminer Fly?

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/.

  Citation × Citation Citation Abstract Copy Title: Does Temperature-Mediated Reproductive Success Drive the Direction of Species Displacement in Two Invasive Species of Leafminer Fly? Author: Wang, Haihong, Xiang, Juncheng, Reitz, Stuart R., Smagghe, Guy, Lei, Zhongren This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Title: Does Temperature-Mediated Reproductive Success Drive the Direction of Species Displacement in Two Invasive Species of Leafminer Fly? Author: Wang, Haihong, Xiang, Juncheng, Reitz, Stuart R., Smagghe, Guy, Lei, Zhongren This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Close

• 119. [Article] Elevated Temperature Alters the Lunar Timing of Planulation in the Brooding Coral Pocillopora damicornis

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/.

  Citation × Citation Citation Abstract Copy Title: Elevated Temperature Alters the Lunar Timing of Planulation in the Brooding Coral Pocillopora damicornis Author: Weis, Virginia M., Liang, Wei-Lo, Fan, Tung-Yung, Crowder, Camerron M. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Title: Elevated Temperature Alters the Lunar Timing of Planulation in the Brooding Coral Pocillopora damicornis Author: Weis, Virginia M., Liang, Wei-Lo, Fan, Tung-Yung, Crowder, Camerron M. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Public Library of Science. The published article can be found at: http://www.plosone.org/. Close

• 120. [Article] Technical Note: Bed conduction impact on fiber optic DTS water temperature measurements

  The final revised paper is available at: http://hdl.handle.net/1957/56579

  Citation × Citation Citation Abstract Copy Title: Technical Note: Bed conduction impact on fiber optic DTS water temperature measurements Author: O'Donnell Meininger, T., Selker, J. S. The final revised paper is available at: http://hdl.handle.net/1957/56579 Title: Technical Note: Bed conduction impact on fiber optic DTS water temperature measurements Author: O'Donnell Meininger, T., Selker, J. S. The final revised paper is available at: http://hdl.handle.net/1957/56579 Close

• 121. [Article] Soil physical conditions and nitrogen fixation of soybeans (Glycine max. Merrill, var. Chippewa 64)

  The effect of soil water suction and soil temperature on rates of transpiration, photosynthesis, respiration and nitrogen fixation of soybean (Glycine max. Merrill, var. Chippewa 64) seedlings was studied. ...

  Citation × Citation Citation Abstract Copy Title: Soil physical conditions and nitrogen fixation of soybeans (Glycine max. Merrill, var. Chippewa 64) Author: Kuo, Tsungmin The effect of soil water suction and soil temperature on rates of transpiration, photosynthesis, respiration and nitrogen fixation of soybean (Glycine max. Merrill, var. Chippewa 64) seedlings was studied. A special apparatus was developed in which the soil water suction of several cells with soybeans growing in them could be maintained independently at a selected temperature. Transpiration was determined by a constant-water level device which recorded the amount of water used over a period of time. Photosynthesis and respiration were measured using an infra-red gas analyzer. The total nitrogen content of plants was measured by the micro-Kjeldahl method at the beginning and end of a ten-day experimental period. Leaf surface areas were determined with an air flow planimeter. In general with increasing soil temperature rates of transpiration, photosynthesis, and nitrogen fixation increased slowly at first and then rapidly until a certain optimum range was reached and decreased at higher temperatures. Maximum rates occurred around soil temperatures, of 30, 27 and 27°C, respectively. The rate of respiration also increased with increasing soil temperature until an optimum range around 27°C was reached and then dropped rapidly as the soil temperature further increased. Rates of photosynthesis, respiration, transpiration and N-fixation decreased steadily with increasing soil water suction. The decrease in the rate of these metabolic processes with increased soil water suction was attributed to effects of changes in viscosity and root cell permeability, stomatal movement and translocation of metabolic substrates. At low soil temperatures the dry matter accumulation seemed to be controlled by the water supply. At higher than optimum soil temperatures the dry dry matter accumulation was very sensitive-to temperature changes and less soil water dependent. When the nitrogen supply from the soil is limiting, the nitrogen fixation may possibly be a most important factor in the metabolic processes and thus the growth of leguminous plants. It is obvious that for such a plant, soil water availability, soil temperature and nodule rhyzobium organism-plant relationships are important. Title: Soil physical conditions and nitrogen fixation of soybeans (Glycine max. Merrill, var. Chippewa 64) Author: Kuo, Tsungmin The effect of soil water suction and soil temperature on rates of transpiration, photosynthesis, respiration and nitrogen fixation of soybean (Glycine max. Merrill, var. Chippewa 64) seedlings was studied. A special apparatus was developed in which the soil water suction of several cells with soybeans growing in them could be maintained independently at a selected temperature. Transpiration was determined by a constant-water level device which recorded the amount of water used over a period of time. Photosynthesis and respiration were measured using an infra-red gas analyzer. The total nitrogen content of plants was measured by the micro-Kjeldahl method at the beginning and end of a ten-day experimental period. Leaf surface areas were determined with an air flow planimeter. In general with increasing soil temperature rates of transpiration, photosynthesis, and nitrogen fixation increased slowly at first and then rapidly until a certain optimum range was reached and decreased at higher temperatures. Maximum rates occurred around soil temperatures, of 30, 27 and 27°C, respectively. The rate of respiration also increased with increasing soil temperature until an optimum range around 27°C was reached and then dropped rapidly as the soil temperature further increased. Rates of photosynthesis, respiration, transpiration and N-fixation decreased steadily with increasing soil water suction. The decrease in the rate of these metabolic processes with increased soil water suction was attributed to effects of changes in viscosity and root cell permeability, stomatal movement and translocation of metabolic substrates. At low soil temperatures the dry matter accumulation seemed to be controlled by the water supply. At higher than optimum soil temperatures the dry dry matter accumulation was very sensitive-to temperature changes and less soil water dependent. When the nitrogen supply from the soil is limiting, the nitrogen fixation may possibly be a most important factor in the metabolic processes and thus the growth of leguminous plants. It is obvious that for such a plant, soil water availability, soil temperature and nodule rhyzobium organism-plant relationships are important. Close

• 122. [Article] Low temperature deformation characteristics of high purity zirconium single crystals

  High purity single crystals of zirconium were produced and mechanically strained in the temperature range from 4.2°K to 293°K. The crystals were produced by thermal treatment with a specially constructed ...

  Citation × Citation Citation Abstract Copy Title: Low temperature deformation characteristics of high purity zirconium single crystals Author: Goodrich, David George High purity single crystals of zirconium were produced and mechanically strained in the temperature range from 4.2°K to 293°K. The crystals were produced by thermal treatment with a specially constructed electron beam zone refiner which provided the abrupt temperature gradient necessary for crystal growth. Specimens were electrolytically machined to have a reduced center section and chemically polished. Both examination under polarized light and Laue back reflection patterns were necessary to select specimens without alpha variants. Single crystals were tested at liquid helium temperature in a cryostat which was constructed for this study. Intermediate test temperatures were obtained with the specimen immersed in the proper refrigerant. The flow stress was determined for strains of 0.02%, 0.1%, and 0.2%. Strain rate was cycled from 0.002 inches per minute to 0.02 inches per minute to obtain data for calculation of activation volumes. The flow stress versus temperature curve was found to level off at a temperature of approximately 120°K which is 330°K lower than the lowest temperature observed previously for the phenomina. A pronounced peak in the curve of activation volume versus temperature was found at 230°K. Two possible explanations are proposed for the peak in activation volume. Inverse strain rate sensitivity was observed in three specimens two of which were tested at room temperature and one in liquid nitrogen. No evidence of basal slip or twinning was found at any temperature. A complete description of the design and operation of the zone refiner and cryostat is given in separate appendixes. Title: Low temperature deformation characteristics of high purity zirconium single crystals Author: Goodrich, David George High purity single crystals of zirconium were produced and mechanically strained in the temperature range from 4.2°K to 293°K. The crystals were produced by thermal treatment with a specially constructed electron beam zone refiner which provided the abrupt temperature gradient necessary for crystal growth. Specimens were electrolytically machined to have a reduced center section and chemically polished. Both examination under polarized light and Laue back reflection patterns were necessary to select specimens without alpha variants. Single crystals were tested at liquid helium temperature in a cryostat which was constructed for this study. Intermediate test temperatures were obtained with the specimen immersed in the proper refrigerant. The flow stress was determined for strains of 0.02%, 0.1%, and 0.2%. Strain rate was cycled from 0.002 inches per minute to 0.02 inches per minute to obtain data for calculation of activation volumes. The flow stress versus temperature curve was found to level off at a temperature of approximately 120°K which is 330°K lower than the lowest temperature observed previously for the phenomina. A pronounced peak in the curve of activation volume versus temperature was found at 230°K. Two possible explanations are proposed for the peak in activation volume. Inverse strain rate sensitivity was observed in three specimens two of which were tested at room temperature and one in liquid nitrogen. No evidence of basal slip or twinning was found at any temperature. A complete description of the design and operation of the zone refiner and cryostat is given in separate appendixes. Close

• 123. [Article] Development of complex perovskite dielectric ceramics for high temperature capacitor applications

  Dielectric ceramics designed for capacitor applications for use in extreme environments, such as high temperatures, high voltages, or high-pressure environments, are in great demand. Existing capacitor ...

  Citation × Citation Citation Abstract Copy Title: Development of complex perovskite dielectric ceramics for high temperature capacitor applications Author: Raengthon, Natthaphon Dielectric ceramics designed for capacitor applications for use in extreme environments, such as high temperatures, high voltages, or high-pressure environments, are in great demand. Existing capacitor technology fails to perform within these extreme conditions or such environments. The development of new dielectric ceramic materials for high temperature capacitor applications is of specific interest in this study. Two major factors that influence the performance of dielectric ceramics, including a high insulation resistance and high permittivity were investigated. Complex perovskites based on BaTiO₃ - Bi(Zn₁/₂Ti₁/₂)O₃ (BT-BZT) compounds are the focus of this study due to the existence of a linear dielectric behavior persisting with high permittivity, which is highly suitable for use in demanding capacitor applications. Compositions of complex perovskite based on BT-BZT compounds were fabricated using a solid-state reaction technique. By understanding conduction mechanisms of pseudo-binary BT-BZT, the high insulation resistance dielectric ceramics can be controlled. Pseudo-ternary BaTiO₃ - Bi(Zn₁/₂Ti₁/₂)O₃ - ABO₃ compounds were also explored, where ABO₃ represents BiInO₃, BiScO₃, and NaNbO₃, in order to develop dielectric ceramics that exhibit a temperature- stable permittivity over a wide temperature range, particularly at high temperatures, while maintaining their high permittivity characteristics. The addition of small concentration of dopants and the control of stoichiometry of the BT-BZT compounds significantly affected the insulation behavior. The improved insulation resistance, especially at high temperatures (> 200 °C), can be obtained via the introduction of Ba-vacancies into the compound. The intrinsic conduction mechanism, the electrically homogeneous microstructure, and the presence of Ba-vacancy - O- vacancy (VBa-VO) defect associates as a trap site were observed to govern the high insulation resistance of the Ba-deficient BT-BZT compounds. In contrast, the electrically inhomogeneous microstructure and an oxygen vacancy-based conduction mechanism were the main factors giving rise to low insulation resistance behavior at high temperatures for the stoichiometric BT-BZT compound. The formation of pseudo-ternary BT-BZT-ABO₃ complex perovskite strongly modified the dielectric characteristics to a more temperature-stable permittivity in the case of ABO₃ is BiInO₃ and BiScO₃. With a combination of pseudo-ternary compositions and control of the non-stoichiometry in the BT-BZT-BiScO₃ system, a temperature stable dielectric response was obtained over a broad temperature ranges (T > 100 °C), with a high permittivity (> 1000), and a high insulation resistance at elevated temperatures (> 200 °C). Additionally, the temperature-stable permittivity could be extended to low temperatures (< -50 °C) to satisfy X9R specifications with pseudo- ternary BT-BZT-NaNbO₃ compounds. The results obtained in this study clearly show that compounds based on BT-BZT complex perovskite are promising candidates for future use as a high permittivity dielectric ceramic for high temperature capacitor applications. Title: Development of complex perovskite dielectric ceramics for high temperature capacitor applications Author: Raengthon, Natthaphon Dielectric ceramics designed for capacitor applications for use in extreme environments, such as high temperatures, high voltages, or high-pressure environments, are in great demand. Existing capacitor technology fails to perform within these extreme conditions or such environments. The development of new dielectric ceramic materials for high temperature capacitor applications is of specific interest in this study. Two major factors that influence the performance of dielectric ceramics, including a high insulation resistance and high permittivity were investigated. Complex perovskites based on BaTiO₃ - Bi(Zn₁/₂Ti₁/₂)O₃ (BT-BZT) compounds are the focus of this study due to the existence of a linear dielectric behavior persisting with high permittivity, which is highly suitable for use in demanding capacitor applications. Compositions of complex perovskite based on BT-BZT compounds were fabricated using a solid-state reaction technique. By understanding conduction mechanisms of pseudo-binary BT-BZT, the high insulation resistance dielectric ceramics can be controlled. Pseudo-ternary BaTiO₃ - Bi(Zn₁/₂Ti₁/₂)O₃ - ABO₃ compounds were also explored, where ABO₃ represents BiInO₃, BiScO₃, and NaNbO₃, in order to develop dielectric ceramics that exhibit a temperature- stable permittivity over a wide temperature range, particularly at high temperatures, while maintaining their high permittivity characteristics. The addition of small concentration of dopants and the control of stoichiometry of the BT-BZT compounds significantly affected the insulation behavior. The improved insulation resistance, especially at high temperatures (> 200 °C), can be obtained via the introduction of Ba-vacancies into the compound. The intrinsic conduction mechanism, the electrically homogeneous microstructure, and the presence of Ba-vacancy - O- vacancy (VBa-VO) defect associates as a trap site were observed to govern the high insulation resistance of the Ba-deficient BT-BZT compounds. In contrast, the electrically inhomogeneous microstructure and an oxygen vacancy-based conduction mechanism were the main factors giving rise to low insulation resistance behavior at high temperatures for the stoichiometric BT-BZT compound. The formation of pseudo-ternary BT-BZT-ABO₃ complex perovskite strongly modified the dielectric characteristics to a more temperature-stable permittivity in the case of ABO₃ is BiInO₃ and BiScO₃. With a combination of pseudo-ternary compositions and control of the non-stoichiometry in the BT-BZT-BiScO₃ system, a temperature stable dielectric response was obtained over a broad temperature ranges (T > 100 °C), with a high permittivity (> 1000), and a high insulation resistance at elevated temperatures (> 200 °C). Additionally, the temperature-stable permittivity could be extended to low temperatures (< -50 °C) to satisfy X9R specifications with pseudo- ternary BT-BZT-NaNbO₃ compounds. The results obtained in this study clearly show that compounds based on BT-BZT complex perovskite are promising candidates for future use as a high permittivity dielectric ceramic for high temperature capacitor applications. Close

• 124. [Article] Geomorphic and Climatic Controls on Water Temperature and Streambed Scour, Copper River Delta, Alaska : Implications for Understanding Climate Change Impacts to the Pacific Salmon Egg Incubation Environment

  Pacific salmon (Oncorhynchus spp.) face numerous challenges associated with climate change. Most research has emphasized the potential effects of elevated summer water temperatures; however, climatic changes ...

  Citation × Citation Citation Abstract Copy Title: Geomorphic and Climatic Controls on Water Temperature and Streambed Scour, Copper River Delta, Alaska : Implications for Understanding Climate Change Impacts to the Pacific Salmon Egg Incubation Environment Author: Adelfio, Luca A. Pacific salmon (Oncorhynchus spp.) face numerous challenges associated with climate change. Most research has emphasized the potential effects of elevated summer water temperatures; however, climatic changes are also projected to significantly alter incubation and rearing habitats during the late autumn, winter, and spring months ("the incubation period"). Along the southern coast of Alaska, projected climatic changes include increases in the frequency of above freezing winter temperatures and reductions in low elevation snowpack. These changes are expected to impact the hydrology of salmon streams by increasing both water temperatures and the magnitude and frequency of winter floods. Projected increases in water temperature may accelerate embryo development, impacting juvenile viability. More powerful and more frequent winter floods could reduce the survival of salmon eggs by increasing streambed scour. Here, I investigate climatic and geomorphic controls of water temperature and potential scour depth at salmon spawning and rearing sites on the Copper River Delta, a large coastal foreland in Southcentral Alaska. In chapter 2, I utilized surface water temperature data collected at 18 sites to test the abilities of regression models to project year-round water temperature metrics based on catchment characteristics (elevation, slope, area, percent lake area) and air-water temperature correlations. Considerable variability in water temperature was observed on spatial and temporal scales. Both temperature maxima and the frequency of freezing conditions were positively correlated with percent lake area and negatively correlated with catchment elevation and slope. Sites with upwelling groundwater and sites with high-relief, high elevation catchments exhibited lower thermal sensitivity and water temperatures are anticipated to be less impacted by projected climatic changes. In chapter 3, I utilized surface and streambed water temperature data collected at 8 spawning sites to compare water temperatures during incubation periods under climatological mean ("severe winter") and anomalously warm ("mild winter") conditions. I also collected stream stage and channel geometry data at a subset of 3 sites and calculated streambed scour at bankfull discharge. The magnitude and seasonality of accumulated thermal units (°C/day) (ATU) within spawning gravels varied significantly between severe and mild winters at shallow flowpath sites, but not at upwelling groundwater sites. When seasonal snow and ice was absent, increases in spring ATU at shallow flowpath sites were particularly significant. Modelled mean scour depths varied from 3 to 72 cm, suggesting the impacts of scour on egg mortality will be variable across the landscape. I conclude that the impacts of projected climatic changes are likely to vary in magnitude across the Copper River Delta, even at small spatial scales, due to heterogeneity in climatic and geomorphic controls. Title: Geomorphic and Climatic Controls on Water Temperature and Streambed Scour, Copper River Delta, Alaska : Implications for Understanding Climate Change Impacts to the Pacific Salmon Egg Incubation Environment Author: Adelfio, Luca A. Pacific salmon (Oncorhynchus spp.) face numerous challenges associated with climate change. Most research has emphasized the potential effects of elevated summer water temperatures; however, climatic changes are also projected to significantly alter incubation and rearing habitats during the late autumn, winter, and spring months ("the incubation period"). Along the southern coast of Alaska, projected climatic changes include increases in the frequency of above freezing winter temperatures and reductions in low elevation snowpack. These changes are expected to impact the hydrology of salmon streams by increasing both water temperatures and the magnitude and frequency of winter floods. Projected increases in water temperature may accelerate embryo development, impacting juvenile viability. More powerful and more frequent winter floods could reduce the survival of salmon eggs by increasing streambed scour. Here, I investigate climatic and geomorphic controls of water temperature and potential scour depth at salmon spawning and rearing sites on the Copper River Delta, a large coastal foreland in Southcentral Alaska. In chapter 2, I utilized surface water temperature data collected at 18 sites to test the abilities of regression models to project year-round water temperature metrics based on catchment characteristics (elevation, slope, area, percent lake area) and air-water temperature correlations. Considerable variability in water temperature was observed on spatial and temporal scales. Both temperature maxima and the frequency of freezing conditions were positively correlated with percent lake area and negatively correlated with catchment elevation and slope. Sites with upwelling groundwater and sites with high-relief, high elevation catchments exhibited lower thermal sensitivity and water temperatures are anticipated to be less impacted by projected climatic changes. In chapter 3, I utilized surface and streambed water temperature data collected at 8 spawning sites to compare water temperatures during incubation periods under climatological mean ("severe winter") and anomalously warm ("mild winter") conditions. I also collected stream stage and channel geometry data at a subset of 3 sites and calculated streambed scour at bankfull discharge. The magnitude and seasonality of accumulated thermal units (°C/day) (ATU) within spawning gravels varied significantly between severe and mild winters at shallow flowpath sites, but not at upwelling groundwater sites. When seasonal snow and ice was absent, increases in spring ATU at shallow flowpath sites were particularly significant. Modelled mean scour depths varied from 3 to 72 cm, suggesting the impacts of scour on egg mortality will be variable across the landscape. I conclude that the impacts of projected climatic changes are likely to vary in magnitude across the Copper River Delta, even at small spatial scales, due to heterogeneity in climatic and geomorphic controls. Close

• 125. [Article] Stream temperatures, riparian vegetation, and channel morphology in the Upper Grande Ronde River Watershed, Oregon

  The Upper Grande Ronde River Watershed in northeastern Oregon is considered important habitat for threatened stocks of chinook salmon (Oncorhynchus tshawytscha). Documented reductions in channel complexity ...

  Citation × Citation Citation Abstract Copy Title: Stream temperatures, riparian vegetation, and channel morphology in the Upper Grande Ronde River Watershed, Oregon Author: Bohle, Todd S. The Upper Grande Ronde River Watershed in northeastern Oregon is considered important habitat for threatened stocks of chinook salmon (Oncorhynchus tshawytscha). Documented reductions in channel complexity and riparian vegetation within the watershed have increased concern over loss of viable habitat. An important component of salmonid habitat is stream temperature during critical summer periods. In general, annual maximum stream temperatures and diurnal fluctuations in the Upper Grande Ronde River were found to reflect local reach characteristics, position in the drainage, and large-scale changes in valley shape. Stream temperatures on the Grande Ronde River at a distance of 71 km from the watershed divide exceeded 14°C, the "upper preferred temperature" for chinook salmon, more than 90% of time in July of 1991 and in July and August of 1992. While the occurrence of temperatures above 14°C were less common in the headwaters of the Grande Ronde River, downstream of a large meadow (i.e., Vey Meadow) (29 km from the divide) 14°C was exceeded at least 60% of the time during the same three month period. Seven-day maximum stream temperatures on the Upper Grande Ronde River ranged between 17.9°C and 26.6°C in 1991 and between 19.1°C and 26.7°C in 1992. Diel fluctuations on the mainstem were greatest immediately below Vey Meadow (about 12°C) but tended to stabilize at approximately 8°C at distances of over 49 km from the divide. Maximum stream temperatures in tributaries of the Upper Grande Ronde River varied by as much as 11°C (during 1992), reflecting large differences in stream cover, aspect, and flow. The timing of annual maximums seemed to be strongly linked to aspect during 1992. In addition, the high-elevation, forested tributaries had annual maximum stream temperatures and diel fluctuations which were 3°C lower than those associated with more open, low-elevation sites. Relationships between stream temperatures, riparian vegetation, and channel morphology characteristics were evaluated for 11 tributary reaches. Differences in stream cover, average flow velocity, bankfull depth and percent undercut bank were found to be significantly (p <0.1) related to maximum stream temperatures and/or average August diel fluctuations based on linear regression models. A stream temperature prediction model (i.e., TEMP-86) was found to be an accurate predictor of average hourly strew temperatures through short 250-m long reaches. An average WSTAT (a measure of model accuracy) of -0.18°C was calculated based on 11 reaches though two reaches led to consistent over- and under-predictions of downstream temperatures. A series of temperature simulations using TEMP-86 and combinations of wetted width and percent stream cover suggest that lower maximum daily stream temperatures would be observed through altered reaches if concurrent changes in both parameters occurred. Title: Stream temperatures, riparian vegetation, and channel morphology in the Upper Grande Ronde River Watershed, Oregon Author: Bohle, Todd S. The Upper Grande Ronde River Watershed in northeastern Oregon is considered important habitat for threatened stocks of chinook salmon (Oncorhynchus tshawytscha). Documented reductions in channel complexity and riparian vegetation within the watershed have increased concern over loss of viable habitat. An important component of salmonid habitat is stream temperature during critical summer periods. In general, annual maximum stream temperatures and diurnal fluctuations in the Upper Grande Ronde River were found to reflect local reach characteristics, position in the drainage, and large-scale changes in valley shape. Stream temperatures on the Grande Ronde River at a distance of 71 km from the watershed divide exceeded 14°C, the "upper preferred temperature" for chinook salmon, more than 90% of time in July of 1991 and in July and August of 1992. While the occurrence of temperatures above 14°C were less common in the headwaters of the Grande Ronde River, downstream of a large meadow (i.e., Vey Meadow) (29 km from the divide) 14°C was exceeded at least 60% of the time during the same three month period. Seven-day maximum stream temperatures on the Upper Grande Ronde River ranged between 17.9°C and 26.6°C in 1991 and between 19.1°C and 26.7°C in 1992. Diel fluctuations on the mainstem were greatest immediately below Vey Meadow (about 12°C) but tended to stabilize at approximately 8°C at distances of over 49 km from the divide. Maximum stream temperatures in tributaries of the Upper Grande Ronde River varied by as much as 11°C (during 1992), reflecting large differences in stream cover, aspect, and flow. The timing of annual maximums seemed to be strongly linked to aspect during 1992. In addition, the high-elevation, forested tributaries had annual maximum stream temperatures and diel fluctuations which were 3°C lower than those associated with more open, low-elevation sites. Relationships between stream temperatures, riparian vegetation, and channel morphology characteristics were evaluated for 11 tributary reaches. Differences in stream cover, average flow velocity, bankfull depth and percent undercut bank were found to be significantly (p <0.1) related to maximum stream temperatures and/or average August diel fluctuations based on linear regression models. A stream temperature prediction model (i.e., TEMP-86) was found to be an accurate predictor of average hourly strew temperatures through short 250-m long reaches. An average WSTAT (a measure of model accuracy) of -0.18°C was calculated based on 11 reaches though two reaches led to consistent over- and under-predictions of downstream temperatures. A series of temperature simulations using TEMP-86 and combinations of wetted width and percent stream cover suggest that lower maximum daily stream temperatures would be observed through altered reaches if concurrent changes in both parameters occurred. Close

• 126. [Article] Effects of temperature and ration size on the growth of juvenile Chum salmon, Oncorhynchus keta, in sea water

  The effects of temperature and ration on growth, food consumption, and food conversion efficiency of chum salmon, Oncorhynchus keta, in sea water were studied in two experiments conducted during the spring, ...

  Citation × Citation Citation Abstract Copy Title: Effects of temperature and ration size on the growth of juvenile Chum salmon, Oncorhynchus keta, in sea water Author: Rowan, Gerald Duane The effects of temperature and ration on growth, food consumption, and food conversion efficiency of chum salmon, Oncorhynchus keta, in sea water were studied in two experiments conducted during the spring, summer, and fall, 1973, at the Oregon State University Marine Science Center, Newport, Oregon. The test temperatures employed in the study were nominally 11.0, 13.5, 16.5, and 20.0 C. The fish were fed the Oregon Moist pellet. Rations fed during the first experiment (May 29-July 7) were 3, 6, 9, and 15 percent of the dry body weight of the fish per day. Rations fed during the second experiment (Sept. 28-Nov. 7) were 3, 8, 13, and 18%/day. The growth rates of the fish increased with an increase in ration level at all test temperatures. Growth during the first experiment was markedly lower than during the second experiment at each ration level. Growth rates during both experiments were generally higher at 13.5 C than at lower or higher temperatures. During the first experiment, growth rates at the highest test temperatures (16.5 and 20.0 C) were positive only at the highest ration level (15%/day). Values of growth rate during the second experiment were positive at all but the lowest level (3%/day) at all test temperatures. Food conversion efficiency was found to be directly related to ration level and inversely related to temperature. At low consumption rates, increases in temperature markedly reduced efficiency. As ration levels increased, the effects of temperature were ameliorated. The highest conversion efficiencies at the lowest temperatures reflect the decrease in maintenance rations with a decrease in temperature. As with growth, the highest conversion efficiencies were generally found at 13.5 C. Maximum food consumption rates and maintenance rations were generally lower in experiment U than in experiment I. These differences in consumption and maintenance may be attributable to the larger sizes of fish used in the second experiment than in the first experiment. The number of deaths resulting from Vibrio disease during experiment I was found to be directly related to temperature and inversely related to ration level. Mortality resulting from Vibrio disease during experiment II was generally highest at the highest temperatures. Unlike experiment I, there was no clear relationship between mortality and ration level during the second experiment. The results of the study suggest that elevation of sea water temperatures beyond approximately 13.5 C does not benefit the growth of chum salmon, but the extent to which disease may have influenced the growth and food relationships of the fish at elevated temperatures could not be adequately evaluated. Further studies to determine the temperatures most favorable for the culture of chum salmon should be undertaken upon development of methods for the control of Vibrio disease. Title: Effects of temperature and ration size on the growth of juvenile Chum salmon, Oncorhynchus keta, in sea water Author: Rowan, Gerald Duane The effects of temperature and ration on growth, food consumption, and food conversion efficiency of chum salmon, Oncorhynchus keta, in sea water were studied in two experiments conducted during the spring, summer, and fall, 1973, at the Oregon State University Marine Science Center, Newport, Oregon. The test temperatures employed in the study were nominally 11.0, 13.5, 16.5, and 20.0 C. The fish were fed the Oregon Moist pellet. Rations fed during the first experiment (May 29-July 7) were 3, 6, 9, and 15 percent of the dry body weight of the fish per day. Rations fed during the second experiment (Sept. 28-Nov. 7) were 3, 8, 13, and 18%/day. The growth rates of the fish increased with an increase in ration level at all test temperatures. Growth during the first experiment was markedly lower than during the second experiment at each ration level. Growth rates during both experiments were generally higher at 13.5 C than at lower or higher temperatures. During the first experiment, growth rates at the highest test temperatures (16.5 and 20.0 C) were positive only at the highest ration level (15%/day). Values of growth rate during the second experiment were positive at all but the lowest level (3%/day) at all test temperatures. Food conversion efficiency was found to be directly related to ration level and inversely related to temperature. At low consumption rates, increases in temperature markedly reduced efficiency. As ration levels increased, the effects of temperature were ameliorated. The highest conversion efficiencies at the lowest temperatures reflect the decrease in maintenance rations with a decrease in temperature. As with growth, the highest conversion efficiencies were generally found at 13.5 C. Maximum food consumption rates and maintenance rations were generally lower in experiment U than in experiment I. These differences in consumption and maintenance may be attributable to the larger sizes of fish used in the second experiment than in the first experiment. The number of deaths resulting from Vibrio disease during experiment I was found to be directly related to temperature and inversely related to ration level. Mortality resulting from Vibrio disease during experiment II was generally highest at the highest temperatures. Unlike experiment I, there was no clear relationship between mortality and ration level during the second experiment. The results of the study suggest that elevation of sea water temperatures beyond approximately 13.5 C does not benefit the growth of chum salmon, but the extent to which disease may have influenced the growth and food relationships of the fish at elevated temperatures could not be adequately evaluated. Further studies to determine the temperatures most favorable for the culture of chum salmon should be undertaken upon development of methods for the control of Vibrio disease. Close

• 127. [Article] Prediction of low temperature cracking of asphalt concrete mixtures with thermal stress restrained specimen test results

  Low temperature cracking is attributed to tensile stresses induced in an asphalt concrete pavement that develop when the pavement is subjected to a cold temperature. Cracking results in poor ride quality ...

  Citation × Citation Citation Abstract Copy Title: Prediction of low temperature cracking of asphalt concrete mixtures with thermal stress restrained specimen test results Author: Kanerva, Hannele K. Low temperature cracking is attributed to tensile stresses induced in an asphalt concrete pavement that develop when the pavement is subjected to a cold temperature. Cracking results in poor ride quality and a reduction in service life of the pavement. Low temperature cracking has been predicted by regression equations, mechanistic approaches and by simulation measurements. The purpose of the study reported herein is to (1) evaluate the Thermal Stress Restrained Specimen Test (TSRST) as an accelerated performance test to simulate low temperature cracking of asphalt concrete mixtures and (2) develop a deterministic and probabilistic model to predict low temperature cracking with TSRST results. Construction histories, cracking observations and temperature data were collected for five test roads in Alaska, Pennsylvania and Finland. A full scale and fully controlled low temperature cracking test program was conducted at the U.S. Army Cold Regions Research and Engineering Laboratory (USACRREL). Specimens were fabricated in the laboratory with original asphalt cements and aggregates from the test roads. In addition, asphalt concrete pavement specimens were cut from the test sections. The TSRST results obtained for these samples were correlated with the field observations. Based on a statistical analysis of the data, the TSRST fracture temperature is associated with the field cracking temperature and crack frequency for the test roads where mixture properties dominated low temperature cracking. It was concluded that the TSRST can be used to simulate low temperature cracking of asphalt concrete mixtures. A deterministic and a probabilistic model were developed to predict crack spacing as a function of time using the TSRST results, pavement thickness and bulk density, pavement restraint conditions and air temperature. The affect of aging on pavement properties was incorporated in the models by predicting the field aging with Long Term Oven Aging (LTOA) treatment in the laboratory. The calculation of the crack spacing is based on the theory that the pavement slab cracks when the pavement temperature reaches the cracking temperature of the mixture and the slab is fully restrained. The deterministic model predicts crack spacing with time whereas the probabilistic model predicts crack spacing and its variation with time and yields the reliability of the design with regard to a minimum acceptable crack spacing criterion defined by road authorities. The models were verified by comparing the predicted crack spacings for the five test roads to the observed crack spacings. The probabilistic model is recommended for use in predicting the low temperature cracking of asphalt concrete mixtures. Title: Prediction of low temperature cracking of asphalt concrete mixtures with thermal stress restrained specimen test results Author: Kanerva, Hannele K. Low temperature cracking is attributed to tensile stresses induced in an asphalt concrete pavement that develop when the pavement is subjected to a cold temperature. Cracking results in poor ride quality and a reduction in service life of the pavement. Low temperature cracking has been predicted by regression equations, mechanistic approaches and by simulation measurements. The purpose of the study reported herein is to (1) evaluate the Thermal Stress Restrained Specimen Test (TSRST) as an accelerated performance test to simulate low temperature cracking of asphalt concrete mixtures and (2) develop a deterministic and probabilistic model to predict low temperature cracking with TSRST results. Construction histories, cracking observations and temperature data were collected for five test roads in Alaska, Pennsylvania and Finland. A full scale and fully controlled low temperature cracking test program was conducted at the U.S. Army Cold Regions Research and Engineering Laboratory (USACRREL). Specimens were fabricated in the laboratory with original asphalt cements and aggregates from the test roads. In addition, asphalt concrete pavement specimens were cut from the test sections. The TSRST results obtained for these samples were correlated with the field observations. Based on a statistical analysis of the data, the TSRST fracture temperature is associated with the field cracking temperature and crack frequency for the test roads where mixture properties dominated low temperature cracking. It was concluded that the TSRST can be used to simulate low temperature cracking of asphalt concrete mixtures. A deterministic and a probabilistic model were developed to predict crack spacing as a function of time using the TSRST results, pavement thickness and bulk density, pavement restraint conditions and air temperature. The affect of aging on pavement properties was incorporated in the models by predicting the field aging with Long Term Oven Aging (LTOA) treatment in the laboratory. The calculation of the crack spacing is based on the theory that the pavement slab cracks when the pavement temperature reaches the cracking temperature of the mixture and the slab is fully restrained. The deterministic model predicts crack spacing with time whereas the probabilistic model predicts crack spacing and its variation with time and yields the reliability of the design with regard to a minimum acceptable crack spacing criterion defined by road authorities. The models were verified by comparing the predicted crack spacings for the five test roads to the observed crack spacings. The probabilistic model is recommended for use in predicting the low temperature cracking of asphalt concrete mixtures. Close

• 128. [Article] Physiological and biochemical characteristics of two cultivars of tall fescue (Festuca arundinacea Schreb.) under different environmental conditions

  Two cultivars of tall fescue (Festuca arundinacea Schreb.) with contrasting growth habits were studied under field and growth chamber conditions. Fawn, an established cultivar since 1964, and TFM, an experimental ...

  Citation × Citation Citation Abstract Copy Title: Physiological and biochemical characteristics of two cultivars of tall fescue (Festuca arundinacea Schreb.) under different environmental conditions Author: Fino, Antonio Carlos Two cultivars of tall fescue (Festuca arundinacea Schreb.) with contrasting growth habits were studied under field and growth chamber conditions. Fawn, an established cultivar since 1964, and TFM, an experimental line, were observed to grow better during spring and fall months respectively, in the field. Different temperature regimes of 10/4, 16/4, 27/10, and 32/16°C were employed to study the effect of temperatures on the growth and biochemical characteristics of these two cultivars. Fawn was significantly greater than TFM across the three harvests in dry matter production. There were no significant differences between Fawn and TFM in watersoluble carbohydrates (WSC) across the three harvest material. During the seven month period, there were also no significant differences in water-soluble carbohydrates and crude protein between the two cultivars. Stems had a higher concentration of WSC but were lower in crude protein than leaves in both cultivars. Fawn also produced more foliage dry matter (for the first and second harvests) across all temperatures tested. In regrowth, TFM and Fawn grew better at low and high temperatures respectively. This was expected on the basis of field results. Fawn was significantly greater than TFM in WSC and free sugars in both the first and second harvests and in the regrowth but in percent fructosans there were no significant differences between cultivars. TFM was significantly greater than Fawn in percent crude protein in both first and second harvest and regrowth. Temperature affected crude protein and WSC content as temperature increased, WSC, fructosan, and free sugars content decreased. Fructosans were lower in the regrowth material than either the first or second harvest. Percent crude protein in the foliage dry matter increased as temperature increased except in the regrowth where the lowest and highest temperatures showed the highest concentration. Tillering was higher in Fawn, and the most favorable temperature for both cultivars was at 16/4°C. Root dry weight was lower in Fawn, however, the concentration of WSC, fructosans, and free sugars in the roots were higher in Fawn than TFM. These sugar components were lower in the root material than in the foliage or regrowth material. There were no differences in the mean relative growth rate between cultivars, although Fawn was highest at the high temperatures, with TFM being higher at the three lower temperatures. There were no differences in net carbon exchange in the light or gross photosynthesis between these two cultivars, but Fawn was significantly greater in dark respiration at the highest temperature. Dark respiration and gross photosynthesis were higher at the highest temperatures in each cultivar. TFM was significantly higher than Fawn in leaf area at the lower temperatures, but leaf area was lower at the highest temperature for both cultivars. Fawn was significantly higher than TFM in perloline content across temperatures. In both cultivars, the higher temperatures had higher perloline content. Title: Physiological and biochemical characteristics of two cultivars of tall fescue (Festuca arundinacea Schreb.) under different environmental conditions Author: Fino, Antonio Carlos Two cultivars of tall fescue (Festuca arundinacea Schreb.) with contrasting growth habits were studied under field and growth chamber conditions. Fawn, an established cultivar since 1964, and TFM, an experimental line, were observed to grow better during spring and fall months respectively, in the field. Different temperature regimes of 10/4, 16/4, 27/10, and 32/16°C were employed to study the effect of temperatures on the growth and biochemical characteristics of these two cultivars. Fawn was significantly greater than TFM across the three harvests in dry matter production. There were no significant differences between Fawn and TFM in watersoluble carbohydrates (WSC) across the three harvest material. During the seven month period, there were also no significant differences in water-soluble carbohydrates and crude protein between the two cultivars. Stems had a higher concentration of WSC but were lower in crude protein than leaves in both cultivars. Fawn also produced more foliage dry matter (for the first and second harvests) across all temperatures tested. In regrowth, TFM and Fawn grew better at low and high temperatures respectively. This was expected on the basis of field results. Fawn was significantly greater than TFM in WSC and free sugars in both the first and second harvests and in the regrowth but in percent fructosans there were no significant differences between cultivars. TFM was significantly greater than Fawn in percent crude protein in both first and second harvest and regrowth. Temperature affected crude protein and WSC content as temperature increased, WSC, fructosan, and free sugars content decreased. Fructosans were lower in the regrowth material than either the first or second harvest. Percent crude protein in the foliage dry matter increased as temperature increased except in the regrowth where the lowest and highest temperatures showed the highest concentration. Tillering was higher in Fawn, and the most favorable temperature for both cultivars was at 16/4°C. Root dry weight was lower in Fawn, however, the concentration of WSC, fructosans, and free sugars in the roots were higher in Fawn than TFM. These sugar components were lower in the root material than in the foliage or regrowth material. There were no differences in the mean relative growth rate between cultivars, although Fawn was highest at the high temperatures, with TFM being higher at the three lower temperatures. There were no differences in net carbon exchange in the light or gross photosynthesis between these two cultivars, but Fawn was significantly greater in dark respiration at the highest temperature. Dark respiration and gross photosynthesis were higher at the highest temperatures in each cultivar. TFM was significantly higher than Fawn in leaf area at the lower temperatures, but leaf area was lower at the highest temperature for both cultivars. Fawn was significantly higher than TFM in perloline content across temperatures. In both cultivars, the higher temperatures had higher perloline content. Close

• 129. [Article] Bright air : geoprocessing thermal imagery to map the nocturnal dynamics of the boundary layer in a mountain valley

  A thermal infrared (TIR) camera is used to remotely sense the foliage temperature in a mountain valley. The foliage temperature is used as a proxy for air temperature and can be used to study and map the ...

  Citation × Citation Citation Abstract Copy Title: Bright air : geoprocessing thermal imagery to map the nocturnal dynamics of the boundary layer in a mountain valley Author: Johnson, Christopher (Raymond Christopher) A thermal infrared (TIR) camera is used to remotely sense the foliage temperature in a mountain valley. The foliage temperature is used as a proxy for air temperature and can be used to study and map the dynamics of the nocturnal, weak-wind boundary layer in this valley. All radiative flux not originating from the forest canopy must be filtered out of the captured imagery. Once the image has been filtered it must be georeferenced and orthorectified before useful analyses can be performed. After geoprocessing is complete, a spatially explicit time series of temperatures for an entire forested mountain valley will be available for further exploitation. The geoprocessed thermal imagery can, when combined with various data recorded in situ, yield data sets such as sensible heat flux at the canopy surface, potential temperature profiles, the adiabatic lapse rate in the watershed, the state of static stability in the watershed, and to map cold-air pool dynamics. Evidence was established that two concepts underlying the Bright Air study are valid for this study site. The first is that a TIR camera can accurately record foliage canopy temperature. The second is that on clear nights, foliage canopy temperature can be a proxy for the temperature of air immediately adjacent to the canopy. This study indicates that a TIR camera can accurately measure foliage canopy temperature on clear nights. Furthermore, the study indicates that on clear or intermittently cloudy nights, foliage canopy temperatures as measured by a TIR camera can be a proxy for the temperature of air immediately adjacent to the canopy. A process to georeference and orthorectify thermal imagery was selected and a tool to geoprocess the thermal imagery was created. Vertical profiles of potential temperature in the study area were created for times of interest and classified according to flow regimes. Dominant flow regimes were found to correlate well with earlier studies. Cold-air pool formation and drainage evolution were characterized for several clear nights. Nocturnal cold-air dynamics in the study area do not agree with common explanations of behavior of cold-air pools and drainage in mountain valleys. Up-valley flow patterns in the watershed indicate that nocturnal flows in mountain valleys are not driven solely by gravity. For the nights studied, flows in the watershed interact with flows from other connected basins and have identifiable patterns and typical evolutionary stages. Title: Bright air : geoprocessing thermal imagery to map the nocturnal dynamics of the boundary layer in a mountain valley Author: Johnson, Christopher (Raymond Christopher) A thermal infrared (TIR) camera is used to remotely sense the foliage temperature in a mountain valley. The foliage temperature is used as a proxy for air temperature and can be used to study and map the dynamics of the nocturnal, weak-wind boundary layer in this valley. All radiative flux not originating from the forest canopy must be filtered out of the captured imagery. Once the image has been filtered it must be georeferenced and orthorectified before useful analyses can be performed. After geoprocessing is complete, a spatially explicit time series of temperatures for an entire forested mountain valley will be available for further exploitation. The geoprocessed thermal imagery can, when combined with various data recorded in situ, yield data sets such as sensible heat flux at the canopy surface, potential temperature profiles, the adiabatic lapse rate in the watershed, the state of static stability in the watershed, and to map cold-air pool dynamics. Evidence was established that two concepts underlying the Bright Air study are valid for this study site. The first is that a TIR camera can accurately record foliage canopy temperature. The second is that on clear nights, foliage canopy temperature can be a proxy for the temperature of air immediately adjacent to the canopy. This study indicates that a TIR camera can accurately measure foliage canopy temperature on clear nights. Furthermore, the study indicates that on clear or intermittently cloudy nights, foliage canopy temperatures as measured by a TIR camera can be a proxy for the temperature of air immediately adjacent to the canopy. A process to georeference and orthorectify thermal imagery was selected and a tool to geoprocess the thermal imagery was created. Vertical profiles of potential temperature in the study area were created for times of interest and classified according to flow regimes. Dominant flow regimes were found to correlate well with earlier studies. Cold-air pool formation and drainage evolution were characterized for several clear nights. Nocturnal cold-air dynamics in the study area do not agree with common explanations of behavior of cold-air pools and drainage in mountain valleys. Up-valley flow patterns in the watershed indicate that nocturnal flows in mountain valleys are not driven solely by gravity. For the nights studied, flows in the watershed interact with flows from other connected basins and have identifiable patterns and typical evolutionary stages. Close

• 130. [Article] Elevation, thermal environment, and stream temperatures on headwater streams in northeastern Oregon

  A case study examining the relationship between stream temperatures and the thermal environment through which streams flow was conducted on the headwaters of 4 tributaries of the Burnt River (Barney, Elk, ...

  Citation × Citation Citation Abstract Copy Title: Elevation, thermal environment, and stream temperatures on headwater streams in northeastern Oregon Author: Meays, Cynthia L. A case study examining the relationship between stream temperatures and the thermal environment through which streams flow was conducted on the headwaters of 4 tributaries of the Burnt River (Barney, Elk, Greenhorn, and Stevens Creeks) in northeastern Oregon during July through August 1998 and 1999. Barney Creek and Stevens Creek are in adjacent drainages, both with northerly aspects. Barney Creek drainage was completely burned over in 1989 while Stevens Creek vegetation remained intact. Elk Creek had 2 cold water tributaries and groundwater inputs. Greenhorn Creek was much more variable in terms of disturbance and vegetation. Stream discharge and air, soil, and water temperature data were collected at 150 m increments from 1370 to 1830 m elevation on each stream. Analyses compared daily mean air, soil, and water temperatures at each elevation within each stream, year, and month. Mean daily minimum and daily maximum air and water temperatures were also analyzed. For all streams in this study. elevation was significantly associated with air, soil, and water temperatures (p<O.000I). For most cases on each of the streams, mean daily air, soil, and water temperatures increased with every 150 meter drop in elevation. The thermal environment (air and soil surrounding the stream) as well as the stream temperatures responded similarly on each creek. Barney Creek had the overall highest mean daily air, soil, and water temperatures, followed by Greenhorn, Stevens, and Elk Creeks. Barney Creek was burned over in 1989 and had essentially no overstory canopy cover. Elk Creek consistently had the lowest mean daily air, soil and water temperatures. Elk Creek received substantial cold water subsurface and from 2 tributaries. Of the 4 creeks, Stevens Creek consistently had the greatest increases in mean daily air, water, and soil temperatures with descending elevation. Stevens Creek was adjacent to and very similar to Barney Creek with 2 notable differences. Stevens Creek had intact forest overstory canopy and it carried about half the flow of Barney Creek. Greenhorn Creek was the most variable in terms of temperature changes with descending elevation for mean daily air, water, and soil. Greenhorn Creek has been heavily disturbed by mining activity. Elevation was also significant for mean daily maximum temperatures for air, soil, and water (p<O.000I). Mean daily maximum air and water, as well as mean daily minimum water temperatures generally increased with descending elevation on all 4 streams. Mean daily minimum air temperature showed more variation with elevation, and likely reflected patterns of cold air drainage or cold air pockets. Thermal environment, heavily influenced by elevation, appeared to be a major influence on stream temperature. Title: Elevation, thermal environment, and stream temperatures on headwater streams in northeastern Oregon Author: Meays, Cynthia L. A case study examining the relationship between stream temperatures and the thermal environment through which streams flow was conducted on the headwaters of 4 tributaries of the Burnt River (Barney, Elk, Greenhorn, and Stevens Creeks) in northeastern Oregon during July through August 1998 and 1999. Barney Creek and Stevens Creek are in adjacent drainages, both with northerly aspects. Barney Creek drainage was completely burned over in 1989 while Stevens Creek vegetation remained intact. Elk Creek had 2 cold water tributaries and groundwater inputs. Greenhorn Creek was much more variable in terms of disturbance and vegetation. Stream discharge and air, soil, and water temperature data were collected at 150 m increments from 1370 to 1830 m elevation on each stream. Analyses compared daily mean air, soil, and water temperatures at each elevation within each stream, year, and month. Mean daily minimum and daily maximum air and water temperatures were also analyzed. For all streams in this study. elevation was significantly associated with air, soil, and water temperatures (p<O.000I). For most cases on each of the streams, mean daily air, soil, and water temperatures increased with every 150 meter drop in elevation. The thermal environment (air and soil surrounding the stream) as well as the stream temperatures responded similarly on each creek. Barney Creek had the overall highest mean daily air, soil, and water temperatures, followed by Greenhorn, Stevens, and Elk Creeks. Barney Creek was burned over in 1989 and had essentially no overstory canopy cover. Elk Creek consistently had the lowest mean daily air, soil and water temperatures. Elk Creek received substantial cold water subsurface and from 2 tributaries. Of the 4 creeks, Stevens Creek consistently had the greatest increases in mean daily air, water, and soil temperatures with descending elevation. Stevens Creek was adjacent to and very similar to Barney Creek with 2 notable differences. Stevens Creek had intact forest overstory canopy and it carried about half the flow of Barney Creek. Greenhorn Creek was the most variable in terms of temperature changes with descending elevation for mean daily air, water, and soil. Greenhorn Creek has been heavily disturbed by mining activity. Elevation was also significant for mean daily maximum temperatures for air, soil, and water (p<O.000I). Mean daily maximum air and water, as well as mean daily minimum water temperatures generally increased with descending elevation on all 4 streams. Mean daily minimum air temperature showed more variation with elevation, and likely reflected patterns of cold air drainage or cold air pockets. Thermal environment, heavily influenced by elevation, appeared to be a major influence on stream temperature. Close

• 131. [Article] Summertime stream temperatures in the North and South Forks of the Sprague River, south central Oregon

  The Upper Sprague River Watershed (North and South Forks of the Sprague River) in south central Oregon provides important habitat for salmonid species, including native bull trout (Salvelinus confluentus) ...

  Citation × Citation Citation Abstract Copy Title: Summertime stream temperatures in the North and South Forks of the Sprague River, south central Oregon Author: Friedrichsen, Paul T. The Upper Sprague River Watershed (North and South Forks of the Sprague River) in south central Oregon provides important habitat for salmonid species, including native bull trout (Salvelinus confluentus) and redband trout (Oncorhynchus mykiss ssp.). Concern over the loss of viable habitat for these species has increased due to reductions in channel and habitat complexity, and modification of riparian vegetation. Many of the factors affecting habitat quality also influence water temperature, which is an important habitat component of salmonids during the summer months. Maximum stream temperatures and diel fluctuations in the Upper Sprague River System generally reflected local reach characteristics, position in the drainage, and large scale changes in valley shape. Stream temperatures in the North Fork Sprague River (NFSR), at a distance of 35 km from the drainage divide, equalled or exceeded 15°C, the 'upper preferred temperature' for salmonids, 16% and 36% of the time during the seven-consecutive warmest days of 1993 and 1994, respectively. Upstream of Lee Thomas Meadow (LTM), 6.5 km from the drainage divide, 15°C was equalled or exceeded only 1% and 13% of the time during the same period, while below LTM (18.3 km from the drainage divide), 15°C was exceeded 66% and 85% of the time during this sante period. Diel fluctuations in the NFSR were greatest immediately below LTM (>11.8°C), decreasing to <6.0°C below the canyon section at the mouth of the watershed during both 1993 and 1994. In the South Fork Sprague River (SFSR), 15°C was equalled or exceeded 79% and 99% of the time during the seven-consecutive warmest days of 1993 and 1994, respectively, 28.4 km from the divide. At this same distance, the upper lethal limit of 25°C was equalled or exceeded 16% of the time in 1994, representing very stressful or potentially life-threatening conditions for salmonids. Diel fluctuations for the SFSR were >6.5°C both years, the highest values being 9.5°C or greater at 28.4 kin from the divide. Seven-day maximum stream temperatures and diel fluctuations in tributaries of the Upper Sprague River System varied widely during the study period. Maximum stream temperatures varied from 13.8°C to 23.1°C while diel fluctuations varied from 4.8°C to 11.0°C; the highest values corresponding with relatively open, unshaded reaches and the lower values corresponding with shaded, forested reaches. Relationships between stream temperatures, stream cover and channel morphology characteristics were evaluated for eight reaches within the study area. Only stream cover was found to be significantly (p <0.05) related to seven-day maximum stream temperatures, change in stream temperatures, and diurnal fluctuations in stream temperatures based on simple linear regression. When multiple linear regression analysis was used, several combinations of independent variables were found to be significantly (p <0.05) related to seven-day maximum stream temperatures, and/or change in stream temperatures, and/or diurnal fluctuations in stream temperatures. The variables that were consistently part of significant (p <0.05) regressions included: stream cover, wetted width, thalweg depth, width/depth ratio, and reach length. A stream temperature model, SHADOW, was found to be a relatively good predictor of maximum stream temperatures for short (1130 m) reaches and generally a poor predictor for longer (1340-4130 m) reaches. For the three short reaches (1130 m), the average difference between observed and modelled temperatures was 0°C (±0.3°C); for the five longer reaches (1340-4130 m), the average difference was 2.9°C (±0.6°C) indicating that the SHADOW Model over-predicted stream temperatures for these longer reaches. The shortest forested reach was under-predicted by 0.4°C. Temperature simulations for five meadow reaches using SHADOW and multiple regression models suggest that lower maximum stream temperatures would be observed if stream cover were increased. Title: Summertime stream temperatures in the North and South Forks of the Sprague River, south central Oregon Author: Friedrichsen, Paul T. The Upper Sprague River Watershed (North and South Forks of the Sprague River) in south central Oregon provides important habitat for salmonid species, including native bull trout (Salvelinus confluentus) and redband trout (Oncorhynchus mykiss ssp.). Concern over the loss of viable habitat for these species has increased due to reductions in channel and habitat complexity, and modification of riparian vegetation. Many of the factors affecting habitat quality also influence water temperature, which is an important habitat component of salmonids during the summer months. Maximum stream temperatures and diel fluctuations in the Upper Sprague River System generally reflected local reach characteristics, position in the drainage, and large scale changes in valley shape. Stream temperatures in the North Fork Sprague River (NFSR), at a distance of 35 km from the drainage divide, equalled or exceeded 15°C, the 'upper preferred temperature' for salmonids, 16% and 36% of the time during the seven-consecutive warmest days of 1993 and 1994, respectively. Upstream of Lee Thomas Meadow (LTM), 6.5 km from the drainage divide, 15°C was equalled or exceeded only 1% and 13% of the time during the same period, while below LTM (18.3 km from the drainage divide), 15°C was exceeded 66% and 85% of the time during this sante period. Diel fluctuations in the NFSR were greatest immediately below LTM (>11.8°C), decreasing to <6.0°C below the canyon section at the mouth of the watershed during both 1993 and 1994. In the South Fork Sprague River (SFSR), 15°C was equalled or exceeded 79% and 99% of the time during the seven-consecutive warmest days of 1993 and 1994, respectively, 28.4 km from the divide. At this same distance, the upper lethal limit of 25°C was equalled or exceeded 16% of the time in 1994, representing very stressful or potentially life-threatening conditions for salmonids. Diel fluctuations for the SFSR were >6.5°C both years, the highest values being 9.5°C or greater at 28.4 kin from the divide. Seven-day maximum stream temperatures and diel fluctuations in tributaries of the Upper Sprague River System varied widely during the study period. Maximum stream temperatures varied from 13.8°C to 23.1°C while diel fluctuations varied from 4.8°C to 11.0°C; the highest values corresponding with relatively open, unshaded reaches and the lower values corresponding with shaded, forested reaches. Relationships between stream temperatures, stream cover and channel morphology characteristics were evaluated for eight reaches within the study area. Only stream cover was found to be significantly (p <0.05) related to seven-day maximum stream temperatures, change in stream temperatures, and diurnal fluctuations in stream temperatures based on simple linear regression. When multiple linear regression analysis was used, several combinations of independent variables were found to be significantly (p <0.05) related to seven-day maximum stream temperatures, and/or change in stream temperatures, and/or diurnal fluctuations in stream temperatures. The variables that were consistently part of significant (p <0.05) regressions included: stream cover, wetted width, thalweg depth, width/depth ratio, and reach length. A stream temperature model, SHADOW, was found to be a relatively good predictor of maximum stream temperatures for short (1130 m) reaches and generally a poor predictor for longer (1340-4130 m) reaches. For the three short reaches (1130 m), the average difference between observed and modelled temperatures was 0°C (±0.3°C); for the five longer reaches (1340-4130 m), the average difference was 2.9°C (±0.6°C) indicating that the SHADOW Model over-predicted stream temperatures for these longer reaches. The shortest forested reach was under-predicted by 0.4°C. Temperature simulations for five meadow reaches using SHADOW and multiple regression models suggest that lower maximum stream temperatures would be observed if stream cover were increased. Close

• 132. [Article] DRAFT Walla Walla Subbasin Stream Temperature TMDL and Water Quality Management Plan

  Abstract -- This document lays out goals and planning to address elevated stream temperatures in the Walla Walla subbasin in Oregon. The first part establishes the Total Maximum Daily Load as required ...

  Citation × Citation Citation Abstract Copy Title: DRAFT Walla Walla Subbasin Stream Temperature TMDL and Water Quality Management Plan Abstract -- This document lays out goals and planning to address elevated stream temperatures in the Walla Walla subbasin in Oregon. The first part establishes the Total Maximum Daily Load as required by Section 303(d) of the federal Clean Water Act for streams whose quality has been compromised by pollutants or high temperatures. The second part, the Water Quality Management Plan, lays out specific guidelines for attaining the goals of the TMDL. The third part of this document is an extensive analysis of stream temperatures which addresses the vegetation, hydrology, and morphology of the Walla Walla subbasin. Title: DRAFT Walla Walla Subbasin Stream Temperature TMDL and Water Quality Management Plan Abstract -- This document lays out goals and planning to address elevated stream temperatures in the Walla Walla subbasin in Oregon. The first part establishes the Total Maximum Daily Load as required by Section 303(d) of the federal Clean Water Act for streams whose quality has been compromised by pollutants or high temperatures. The second part, the Water Quality Management Plan, lays out specific guidelines for attaining the goals of the TMDL. The third part of this document is an extensive analysis of stream temperatures which addresses the vegetation, hydrology, and morphology of the Walla Walla subbasin. Close

• 133. [Article] Sea surface temperature and salinity conditions in 1969 at Agate Beach and Yaquina Bay, Oregon : a technical report to the Office of Naval Research

  Citation × Citation Citation Abstract Copy Title: Sea surface temperature and salinity conditions in 1969 at Agate Beach and Yaquina Bay, Oregon : a technical report to the Office of Naval Research Author: Thum, Alan Bradley, Gonor, J. J., Oregon State University. Dept. of Oceanography Title: Sea surface temperature and salinity conditions in 1969 at Agate Beach and Yaquina Bay, Oregon : a technical report to the Office of Naval Research Author: Thum, Alan Bradley, Gonor, J. J., Oregon State University. Dept. of Oceanography Close

• 134. [Article] Economic analysis of restoration practices to improve water quality and fish habitat of a large river floodplain : a case study of the Willamette River, Oregon

  In- stream water temperature is one of the most important environmental factors associated with the decline in salmonid populations and their habitats in the Pacific Northwest. Most ecological restoration ...

  Citation × Citation Citation Abstract Copy Title: Economic analysis of restoration practices to improve water quality and fish habitat of a large river floodplain : a case study of the Willamette River, Oregon Author: Seedang, Saichon In- stream water temperature is one of the most important environmental factors associated with the decline in salmonid populations and their habitats in the Pacific Northwest. Most ecological restoration practices that attempt to reduce instream temperatures center on replanting or reestablishing riparian vegetation and increasing flows. However, in a large floodplain river like the Willamette, restoring hyporheic flow may also play an important role in reducing water temperature. The objective of this dissertation is to examine restoration practices that focus on the reduction of water temperatures in the upper mainstem Willamette River, Oregon, for the benefit of salmonid species. Economic information is developed to determine the cost-effectiveness of water temperature reduction strategies. The CEQUAL- W2 water temperature model is used to simulate the effects of upstream combinations of riparian shading and flow increments on downstream water temperatures. Costs associated with these strategies are estimated. These costs consist of the opportunity costs of losing agricultural production, and losing recreation due to flow releases from up-stream reservoirs. The effectiveness of each strategy in reducing water temperature and the associated costs are used to construct a cost-effectiveness frontier. The results indicate that the cumulative effects of shading and flows have little impact on temperature reduction downstream. Even when maximum available resources are allocated to investments in shade and flow increases they cannot lower summer water temperatures sufficiently to meet the state water temperature standard. However, the restoration practices selected from the cost-effectiveness frontiers method do provide ranges of achievable temperature reductions at minimum costs. These results are thus useful management tools when selecting policies to pursue water temperature goals. Hyporheic temperature reduction is also examined. Restoration practices associated with this type of cooling are done through removal/reconnection of the obstacles that are necessary to allow the process of re-creating dynamic channel complexity. The observed significant reduction of summer water temperatures associated with channel complexity indicates that this approach is more flexible in reducing temperature than approaches that rely on flow increments or/and shade. Although the costs associated with the hyporheic approach are substantial, the effects of such a long-term ecological improvement of floodplain habitat may substantially benefit salmonid populations. Title: Economic analysis of restoration practices to improve water quality and fish habitat of a large river floodplain : a case study of the Willamette River, Oregon Author: Seedang, Saichon In- stream water temperature is one of the most important environmental factors associated with the decline in salmonid populations and their habitats in the Pacific Northwest. Most ecological restoration practices that attempt to reduce instream temperatures center on replanting or reestablishing riparian vegetation and increasing flows. However, in a large floodplain river like the Willamette, restoring hyporheic flow may also play an important role in reducing water temperature. The objective of this dissertation is to examine restoration practices that focus on the reduction of water temperatures in the upper mainstem Willamette River, Oregon, for the benefit of salmonid species. Economic information is developed to determine the cost-effectiveness of water temperature reduction strategies. The CEQUAL- W2 water temperature model is used to simulate the effects of upstream combinations of riparian shading and flow increments on downstream water temperatures. Costs associated with these strategies are estimated. These costs consist of the opportunity costs of losing agricultural production, and losing recreation due to flow releases from up-stream reservoirs. The effectiveness of each strategy in reducing water temperature and the associated costs are used to construct a cost-effectiveness frontier. The results indicate that the cumulative effects of shading and flows have little impact on temperature reduction downstream. Even when maximum available resources are allocated to investments in shade and flow increases they cannot lower summer water temperatures sufficiently to meet the state water temperature standard. However, the restoration practices selected from the cost-effectiveness frontiers method do provide ranges of achievable temperature reductions at minimum costs. These results are thus useful management tools when selecting policies to pursue water temperature goals. Hyporheic temperature reduction is also examined. Restoration practices associated with this type of cooling are done through removal/reconnection of the obstacles that are necessary to allow the process of re-creating dynamic channel complexity. The observed significant reduction of summer water temperatures associated with channel complexity indicates that this approach is more flexible in reducing temperature than approaches that rely on flow increments or/and shade. Although the costs associated with the hyporheic approach are substantial, the effects of such a long-term ecological improvement of floodplain habitat may substantially benefit salmonid populations. Close

• 135. [Article] Examining effectiveness of Oregon’s forest practice rules for maintaining warm-season maximum stream temperature patterns in the Oregon Coast Range

  Stream temperature, as an important component of stream ecosystems, can be affected by forest harvesting through removal of riparian shade and changes in hydrology. Riparian Management Areas (RMAs), as ...

  Citation × Citation Citation Abstract Copy Title: Examining effectiveness of Oregon’s forest practice rules for maintaining warm-season maximum stream temperature patterns in the Oregon Coast Range Author: Fleuret, Jennifer Marie Stream temperature, as an important component of stream ecosystems, can be affected by forest harvesting through removal of riparian shade and changes in hydrology. Riparian Management Areas (RMAs), as implemented through the current Oregon Forest Practice Rules, are designed, in part, to maintain stream temperature following forest harvesting. However, effectiveness of RMAs in achieving this outcome is uncertain. The objective of this research was to examine effectiveness of RMAs, as outlined by the current Oregon Forest Practices Act and the Northwest State Forests Management Plan, in maintaining warm-season temperature patterns of streamwater. Twenty-two headwater streams, on either private- or state-owned forestlands in the Oregon Coast Range that encompassed a range of RMA widths and harvest prescriptions, were evaluated for effectiveness of RMAs on stream temperature. A Before-After-Control-Impact/Intervention design was used, and each stream had an upstream control and a downstream treatment reach. Temperature probes were placed 1) at the top of the control reach, 2) at the boundary between the control and treatment reaches, and 3) at the bottom of the treatment reach from June to September for four years starting in 2002. All but one stream have at least two years of pre2 harvest temperature data, and one year of post-harvest temperature data. Selected stream and riparian characteristics were collected every 60 m within the control and treatment reaches once prior to and once following harvest. I hypothesized that RMAs would be effective if pre-harvest warmseason maximum temperature patterns were maintained following harvest treatments. Comparisons of temperature patterns between control and treatment reaches both pre- and post-harvest indicate that my hypothesis should be rejected because warm-season maximum temperature patterns were not maintained when mean values in treatment reaches across all study streams were considered. Difference in temperature gradients between control and treatment reaches averaged 0.6°C, based on two years of pre-harvest and one year of post-harvest data. This indicates that more warming or less cooling occurred in treatment reaches than occurred in control reaches when pre-harvest and post-harvest periods were compared, suggesting that current RMAs for small- and medium fishbearing streams of the Oregon Coast Range are not effective for maintenance of warm-season maximum temperature patterns. Title: Examining effectiveness of Oregon’s forest practice rules for maintaining warm-season maximum stream temperature patterns in the Oregon Coast Range Author: Fleuret, Jennifer Marie Stream temperature, as an important component of stream ecosystems, can be affected by forest harvesting through removal of riparian shade and changes in hydrology. Riparian Management Areas (RMAs), as implemented through the current Oregon Forest Practice Rules, are designed, in part, to maintain stream temperature following forest harvesting. However, effectiveness of RMAs in achieving this outcome is uncertain. The objective of this research was to examine effectiveness of RMAs, as outlined by the current Oregon Forest Practices Act and the Northwest State Forests Management Plan, in maintaining warm-season temperature patterns of streamwater. Twenty-two headwater streams, on either private- or state-owned forestlands in the Oregon Coast Range that encompassed a range of RMA widths and harvest prescriptions, were evaluated for effectiveness of RMAs on stream temperature. A Before-After-Control-Impact/Intervention design was used, and each stream had an upstream control and a downstream treatment reach. Temperature probes were placed 1) at the top of the control reach, 2) at the boundary between the control and treatment reaches, and 3) at the bottom of the treatment reach from June to September for four years starting in 2002. All but one stream have at least two years of pre2 harvest temperature data, and one year of post-harvest temperature data. Selected stream and riparian characteristics were collected every 60 m within the control and treatment reaches once prior to and once following harvest. I hypothesized that RMAs would be effective if pre-harvest warmseason maximum temperature patterns were maintained following harvest treatments. Comparisons of temperature patterns between control and treatment reaches both pre- and post-harvest indicate that my hypothesis should be rejected because warm-season maximum temperature patterns were not maintained when mean values in treatment reaches across all study streams were considered. Difference in temperature gradients between control and treatment reaches averaged 0.6°C, based on two years of pre-harvest and one year of post-harvest data. This indicates that more warming or less cooling occurred in treatment reaches than occurred in control reaches when pre-harvest and post-harvest periods were compared, suggesting that current RMAs for small- and medium fishbearing streams of the Oregon Coast Range are not effective for maintenance of warm-season maximum temperature patterns. Close

• 136. [Article] Method of computing the rate of temperature change in wood and plywood panels when the two opposite surfaces are maintained at different temperatures

  Information reviewed and reaffirmed, September 1956.

  Citation × Citation Citation Abstract Copy Title: Method of computing the rate of temperature change in wood and plywood panels when the two opposite surfaces are maintained at different temperatures Author: MacLean, J. D. (James Donald), Forest Products Laboratory (U.S.) Information reviewed and reaffirmed, September 1956. Title: Method of computing the rate of temperature change in wood and plywood panels when the two opposite surfaces are maintained at different temperatures Author: MacLean, J. D. (James Donald), Forest Products Laboratory (U.S.) Information reviewed and reaffirmed, September 1956. Close

• 137. [Article] Temperature preconditioning of ryegrass (Lolium sp.) seed dormancy

  The purposes of this study were to determine the effects of temperature, nutrients, growth regulators, and culm detachment during seed development on ryegrass seed dormancy and weight. The effects of storage ...

  Citation × Citation Citation Abstract Copy Title: Temperature preconditioning of ryegrass (Lolium sp.) seed dormancy Author: Wiesner, Loren E. The purposes of this study were to determine the effects of temperature, nutrients, growth regulators, and culm detachment during seed development on ryegrass seed dormancy and weight. The effects of storage temperature on seed dormancy were also studied. Seed dormancy of annual (Lolium multiflorum Lam.) and perennial (Lolium perenne L.) ryegrass was evaluated by observing germination in the dark at 30, 25, 20, 15, and 15-25C. Dormant ryegrass seeds failed to germinate at 30 and 25C, but as after-ripening occurred seeds became insensitive to germination temperature. Field-grown ryegrass varieties were found to differ in degree of seed dormancy when grown under the same environment. 'Gulf', 'Florida Rust Resistant', and 'Magnolia' annual and 'NK- 100', 'Manhattan', 'Atempo', 'Petra', and 'Pelo' perennial ryegrass varieties were considered dormant. 'Oobahikari' annual and 'Verna Pajbjerg' and 'Linn' perennial ryegrass varieties were nearly nondormant. Dormancy patterns of greenhouse-grown Manhattan perennial ryegrass seed differed from those of field grown Gulf annual ryegrass. Dormancy of Manhattan was reduced when seeds reached maximum dry weight; whereas, Gulf seeds were dormant at all stages of maturity. A detached culm technique was used in growth chamber and greenhouse studies to determine the effects of nutrients, growth regulators and temperature on seed weight and dormancy. The dormancy response of Gulf seed produced on detached culms was similar to that of seeds from intact plants; lending validity to the use of the detached culm technique in studying seed dormancy. Development of Gulf seed in solutions deficient in nitrogen, phosphorus, and potassium did not significantly reduce dormancy. Phosphorus deficiency was more detrimental to seed weight than deficiencies of nitrogen or potassium. Production of Gulf seed on detached culms in gibberellic acid, benzyladenine and sucrose reduced dormancy. Seed developed in sucrose on culms cut at the soil surface produced the largest seeds. However, these seeds were not equal in size to seeds from intact culms. Gibberellic acid had no effect on seed size, while benzyladenine solution significantly reduced seed weight. Ryegrass seed dormancy and weight were affected by temperature during seed development. Gulf seeds developed at low temperature were dormant; whereas, seeds developed at high temperature were nondormant. The duration of exposure to different temperatures and the stage of development at which the seeds were exposed to high or low temperature also influenced the degree of dormancy. Exposure to one week of low temperature during the ripening stage increased seed dormancy, while the same duration of exposure to high temperature immediately after anthesis reduced seed dormancy. Extended periods of low temperature during seed development increased seed weight, while seed weight was decreased if low temperature preconditioning was delayed until later stages of development. The greatest reduction in seed weight occurred when seeds were exposed to high temperatures during the second week of seed development. In storage studies with seven ryegrass varieties, dormancy was quickly overcome at storage temperatures of 30 and 20C, but storage at 5 and -18C increased dormancy. Title: Temperature preconditioning of ryegrass (Lolium sp.) seed dormancy Author: Wiesner, Loren E. The purposes of this study were to determine the effects of temperature, nutrients, growth regulators, and culm detachment during seed development on ryegrass seed dormancy and weight. The effects of storage temperature on seed dormancy were also studied. Seed dormancy of annual (Lolium multiflorum Lam.) and perennial (Lolium perenne L.) ryegrass was evaluated by observing germination in the dark at 30, 25, 20, 15, and 15-25C. Dormant ryegrass seeds failed to germinate at 30 and 25C, but as after-ripening occurred seeds became insensitive to germination temperature. Field-grown ryegrass varieties were found to differ in degree of seed dormancy when grown under the same environment. 'Gulf', 'Florida Rust Resistant', and 'Magnolia' annual and 'NK- 100', 'Manhattan', 'Atempo', 'Petra', and 'Pelo' perennial ryegrass varieties were considered dormant. 'Oobahikari' annual and 'Verna Pajbjerg' and 'Linn' perennial ryegrass varieties were nearly nondormant. Dormancy patterns of greenhouse-grown Manhattan perennial ryegrass seed differed from those of field grown Gulf annual ryegrass. Dormancy of Manhattan was reduced when seeds reached maximum dry weight; whereas, Gulf seeds were dormant at all stages of maturity. A detached culm technique was used in growth chamber and greenhouse studies to determine the effects of nutrients, growth regulators and temperature on seed weight and dormancy. The dormancy response of Gulf seed produced on detached culms was similar to that of seeds from intact plants; lending validity to the use of the detached culm technique in studying seed dormancy. Development of Gulf seed in solutions deficient in nitrogen, phosphorus, and potassium did not significantly reduce dormancy. Phosphorus deficiency was more detrimental to seed weight than deficiencies of nitrogen or potassium. Production of Gulf seed on detached culms in gibberellic acid, benzyladenine and sucrose reduced dormancy. Seed developed in sucrose on culms cut at the soil surface produced the largest seeds. However, these seeds were not equal in size to seeds from intact culms. Gibberellic acid had no effect on seed size, while benzyladenine solution significantly reduced seed weight. Ryegrass seed dormancy and weight were affected by temperature during seed development. Gulf seeds developed at low temperature were dormant; whereas, seeds developed at high temperature were nondormant. The duration of exposure to different temperatures and the stage of development at which the seeds were exposed to high or low temperature also influenced the degree of dormancy. Exposure to one week of low temperature during the ripening stage increased seed dormancy, while the same duration of exposure to high temperature immediately after anthesis reduced seed dormancy. Extended periods of low temperature during seed development increased seed weight, while seed weight was decreased if low temperature preconditioning was delayed until later stages of development. The greatest reduction in seed weight occurred when seeds were exposed to high temperatures during the second week of seed development. In storage studies with seven ryegrass varieties, dormancy was quickly overcome at storage temperatures of 30 and 20C, but storage at 5 and -18C increased dormancy. Close

• 138. [Article] A multipoint environmental temperature recorder

  A multipoint environmental temperature recorder is described. Some of the many features that recommend the application of this recorder to field studies are multiple input capability, efficient use of ...

  Citation × Citation Citation Abstract Copy Title: A multipoint environmental temperature recorder Author: University of Washington, U.S. International Biological Program. Coniferous Forest Biome, Holbo, Harold Richard A multipoint environmental temperature recorder is described. Some of the many features that recommend the application of this recorder to field studies are multiple input capability, efficient use of chart paper, reliability, and low power consumption from batteries. Design considerations and electrical details are provided. Title: A multipoint environmental temperature recorder Author: University of Washington, U.S. International Biological Program. Coniferous Forest Biome, Holbo, Harold Richard A multipoint environmental temperature recorder is described. Some of the many features that recommend the application of this recorder to field studies are multiple input capability, efficient use of chart paper, reliability, and low power consumption from batteries. Design considerations and electrical details are provided. Close

• 139. [Article] The Influence of Recurrent Modes of Climate Variability on the Occurrence of Winter and Summer Extreme Temperatures over North America

  The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. ...

  Citation × Citation Citation Abstract Copy Title: The Influence of Recurrent Modes of Climate Variability on the Occurrence of Winter and Summer Extreme Temperatures over North America Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2014 The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. Associations between extreme temperature days and months are strongest with the PNA and NAM andweaker for ENSO. In general, the associationwith extremes tends to be stronger onmonthly than daily time scales and for winter as compared to summer. Extreme temperatures are associated with the PNAandNAMin the vicinity of the centers of action of these circulation patterns; however, many extremes also occur on days when the amplitude and polarity of these patterns do not favor their occurrence. In winter, synoptic-scale, transient weather disturbances are important drivers of extreme temperature days; however, many of these smaller-scale events are concurrent with amplified PNA or NAMpatterns. Associations are weaker in summer when other physicalmechanisms affecting the surface energy balance, such as anomalous soilmoisture content, also influence the occurrence of extreme temperatures. Title: The Influence of Recurrent Modes of Climate Variability on the Occurrence of Winter and Summer Extreme Temperatures over North America Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2014 The influence of the Pacific–North American (PNA) pattern, the northern annular mode (NAM), and the El Ni~no–Southern Oscillation (ENSO) on extreme temperature days and months over North America is examined. Associations between extreme temperature days and months are strongest with the PNA and NAM andweaker for ENSO. In general, the associationwith extremes tends to be stronger onmonthly than daily time scales and for winter as compared to summer. Extreme temperatures are associated with the PNAandNAMin the vicinity of the centers of action of these circulation patterns; however, many extremes also occur on days when the amplitude and polarity of these patterns do not favor their occurrence. In winter, synoptic-scale, transient weather disturbances are important drivers of extreme temperature days; however, many of these smaller-scale events are concurrent with amplified PNA or NAMpatterns. Associations are weaker in summer when other physicalmechanisms affecting the surface energy balance, such as anomalous soilmoisture content, also influence the occurrence of extreme temperatures. Close

• 140. [Article] Temperature dependence of dark current in a CCD

  We present data for dark current of a back-illuminated CCD over the temperature range of 222 to 291 K. Using an Arrhenius law, we found that the analysis of the data leads to the relation between the prefactor ...

  Citation × Citation Citation Abstract Copy Title: Temperature dependence of dark current in a CCD Author: Widenhorn, Ralf, Blouke, Morley M., Weber, Alexander, Rest, Armin, Bodegom, Erik Year: 2002 We present data for dark current of a back-illuminated CCD over the temperature range of 222 to 291 K. Using an Arrhenius law, we found that the analysis of the data leads to the relation between the prefactor and the apparent activation energy as described by the Meyer-Neldel rule. However, a more detailed analysis shows that the activation energy for the dark current changes in the temperature range investigated. This transition can be explained by the larger relative importance at high temperatures of the diffusion dark current and at low temperatures by the depletion dark current. The diffusion dark current, characterized by the band gap of silicon, is uniform for all pixels. At low temperatures, the depletion dark current, characterized by half the band gap, prevails, but it varies for different pixels. Dark current spikes are pronounced at low temperatures and can be explained by large concentrations of deep level impurities in those particular pixels. We show that fitting the data with the impurity concentration as the only variable can explain the dark current characteristics of all the pixels on the chip. Title: Temperature dependence of dark current in a CCD Author: Widenhorn, Ralf, Blouke, Morley M., Weber, Alexander, Rest, Armin, Bodegom, Erik Year: 2002 We present data for dark current of a back-illuminated CCD over the temperature range of 222 to 291 K. Using an Arrhenius law, we found that the analysis of the data leads to the relation between the prefactor and the apparent activation energy as described by the Meyer-Neldel rule. However, a more detailed analysis shows that the activation energy for the dark current changes in the temperature range investigated. This transition can be explained by the larger relative importance at high temperatures of the diffusion dark current and at low temperatures by the depletion dark current. The diffusion dark current, characterized by the band gap of silicon, is uniform for all pixels. At low temperatures, the depletion dark current, characterized by half the band gap, prevails, but it varies for different pixels. Dark current spikes are pronounced at low temperatures and can be explained by large concentrations of deep level impurities in those particular pixels. We show that fitting the data with the impurity concentration as the only variable can explain the dark current characteristics of all the pixels on the chip. Close

• 141. [Article] The impact of increasing temperatures on dormancy duration in Calanus finmarchicus

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Oxford ...

  Citation × Citation Citation Abstract Copy Title: The impact of increasing temperatures on dormancy duration in Calanus finmarchicus Author: Runge, Jeffrey, Leising, Andrew, Batchelder, Harold, Saumweber, Whitley, Pierson, James J. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Oxford University Press and can be found at: http://www.oxfordjournals.org/ Title: The impact of increasing temperatures on dormancy duration in Calanus finmarchicus Author: Runge, Jeffrey, Leising, Andrew, Batchelder, Harold, Saumweber, Whitley, Pierson, James J. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Oxford University Press and can be found at: http://www.oxfordjournals.org/ Close

• 142. [Article] A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah

  Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these ...

  Citation × Citation Citation Abstract Copy Title: A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these two quantities. The influence of surface air temperature (SAT), incident solar radiation, and snow cover on surface ground temperature (SGT) variations are explored. SAT variations explain 94% of the variance in SGT. Incident solar radiation is the primary variable governing the remaining variance misfit and is significantly more important during summer months than winter months. A linear relationship between the ground–air temperature difference (ΔT[subscript]sgt-sat) and solar radiation exists with a trend of 1.21 K/(100 W m⁻²); solar radiation accounts for 1.3% of the variance in SGT. The effects of incident solar radiation also account for the 2.47-K average offset in ΔT[subscript]sgt-sat. During the winter, snow cover plays a role in governing SGT variability, but exerts only a minor influence on the annual tracking of ground and air temperatures at the site, accounting for 0.5% of the variance in SGT. These observations of the tracking of SGT and SAT confirm that borehole temperature changes mimic changes in SAT at frequencies appropriate for climatic reconstructions. Title: A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these two quantities. The influence of surface air temperature (SAT), incident solar radiation, and snow cover on surface ground temperature (SGT) variations are explored. SAT variations explain 94% of the variance in SGT. Incident solar radiation is the primary variable governing the remaining variance misfit and is significantly more important during summer months than winter months. A linear relationship between the ground–air temperature difference (ΔT[subscript]sgt-sat) and solar radiation exists with a trend of 1.21 K/(100 W m⁻²); solar radiation accounts for 1.3% of the variance in SGT. The effects of incident solar radiation also account for the 2.47-K average offset in ΔT[subscript]sgt-sat. During the winter, snow cover plays a role in governing SGT variability, but exerts only a minor influence on the annual tracking of ground and air temperatures at the site, accounting for 0.5% of the variance in SGT. These observations of the tracking of SGT and SAT confirm that borehole temperature changes mimic changes in SAT at frequencies appropriate for climatic reconstructions. Close

• 143. [Article] Behavior of juvenile bluefish Pomatomus saltatrix in vertical thermal gradients: influence of season, temperature acclimation and food

  Behavioral responses of juvenile bluefish P. saltatrix L. exposed to cold water in a vertical thermal gradient were measured under controlled laboratory conditions. The temperature regime was similar to ...

  Citation × Citation Citation Abstract Copy Title: Behavior of juvenile bluefish Pomatomus saltatrix in vertical thermal gradients: influence of season, temperature acclimation and food Author: Studholme, Anne L., Bejda, Allen J., Olla, Bori L. Behavioral responses of juvenile bluefish P. saltatrix L. exposed to cold water in a vertical thermal gradient were measured under controlled laboratory conditions. The temperature regime was similar to conditions that these fish encounter in their inshore and estuarine habitats along the Middle Atlantic coast. Measures included activity, schooling, position with respect to depth and temperature, and feeding. The change in behavioral response to temperature coincided with this species southerly fall migration. When food was presented at potentially debilitating temperatures which were normally avoided, motivation to feed modified their avoidance response, with the fish entering these temperatures and successfully feeding. Results are discussed in relation to natural patterns of migration and distribution. Title: Behavior of juvenile bluefish Pomatomus saltatrix in vertical thermal gradients: influence of season, temperature acclimation and food Author: Studholme, Anne L., Bejda, Allen J., Olla, Bori L. Behavioral responses of juvenile bluefish P. saltatrix L. exposed to cold water in a vertical thermal gradient were measured under controlled laboratory conditions. The temperature regime was similar to conditions that these fish encounter in their inshore and estuarine habitats along the Middle Atlantic coast. Measures included activity, schooling, position with respect to depth and temperature, and feeding. The change in behavioral response to temperature coincided with this species southerly fall migration. When food was presented at potentially debilitating temperatures which were normally avoided, motivation to feed modified their avoidance response, with the fish entering these temperatures and successfully feeding. Results are discussed in relation to natural patterns of migration and distribution. Close

• 144. [Article] Last interglacial model-data mismatch of thermal maximum temperatures partially explained

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the European Geosciences Union. The published article can ...

  Citation × Citation Citation Abstract Copy Title: Last interglacial model-data mismatch of thermal maximum temperatures partially explained Author: Renssen, H., Bakker, P. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the European Geosciences Union. The published article can be found at: http://www.climate-of-the-past.net/home.html. Title: Last interglacial model-data mismatch of thermal maximum temperatures partially explained Author: Renssen, H., Bakker, P. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications on behalf of the European Geosciences Union. The published article can be found at: http://www.climate-of-the-past.net/home.html. Close

• 145. [Article] Long-term temperature records following the M[subscript w] 7.9 Wenchuan (China) earthquake are consistent with low friction

  This is the publisher’s final pdf. The published article is copyrighted by the Geological Society of America and can be found at: http://geology.gsapubs.org/.

  Citation × Citation Citation Abstract Copy Title: Long-term temperature records following the M[subscript w] 7.9 Wenchuan (China) earthquake are consistent with low friction Author: Brodsky, Emily E., Xue, Lian, et al., Li, Haibing, Harris, Robert N. This is the publisher’s final pdf. The published article is copyrighted by the Geological Society of America and can be found at: http://geology.gsapubs.org/. Title: Long-term temperature records following the M[subscript w] 7.9 Wenchuan (China) earthquake are consistent with low friction Author: Brodsky, Emily E., Xue, Lian, et al., Li, Haibing, Harris, Robert N. This is the publisher’s final pdf. The published article is copyrighted by the Geological Society of America and can be found at: http://geology.gsapubs.org/. Close

• 146. [Article] Estimating the economic net returns of Oregon & Washington forests with regard to climate change

  Little work has been conducted regarding the net returns of forest lands. The Ricardian model is ripe with potential to estimate the effects of climate on net returns to forestry. Multiple linear regression ...

  Citation × Citation Citation Abstract Copy Title: Estimating the economic net returns of Oregon & Washington forests with regard to climate change Author: Johnson, Zoe I. Little work has been conducted regarding the net returns of forest lands. The Ricardian model is ripe with potential to estimate the effects of climate on net returns to forestry. Multiple linear regression allows each climate variable to measure its effect of net returns with the assumption of all other factors being fixed. Independent variables of average temperature (°C), average temperature squared (°C²), average precipitation (mm), average precipitation squared (mm2), maximum August temperature (°C), and minimum December temperature (°C) were scaled by year using dummy variables to output the dependent variable of real net returns (USD 2010) per county of tree species. This OLS linear regression showed annual precipitation, marginal precipitation, and maximum temperature experienced by forests to affect the net returns they produced. Increased precipitation is expected to increase net returns to forests while higher maximum temperatures will negatively impact net returns in Douglas Fir regions and positively affect pine regions. Precipitation is linearly related to forest net returns, while temperature is not linearly related. With this finding, various areas of Oregon and Washington that are expected to experience heavier precipitation due to climate change should expect more net returns from their forestlands. Title: Estimating the economic net returns of Oregon & Washington forests with regard to climate change Author: Johnson, Zoe I. Little work has been conducted regarding the net returns of forest lands. The Ricardian model is ripe with potential to estimate the effects of climate on net returns to forestry. Multiple linear regression allows each climate variable to measure its effect of net returns with the assumption of all other factors being fixed. Independent variables of average temperature (°C), average temperature squared (°C²), average precipitation (mm), average precipitation squared (mm2), maximum August temperature (°C), and minimum December temperature (°C) were scaled by year using dummy variables to output the dependent variable of real net returns (USD 2010) per county of tree species. This OLS linear regression showed annual precipitation, marginal precipitation, and maximum temperature experienced by forests to affect the net returns they produced. Increased precipitation is expected to increase net returns to forests while higher maximum temperatures will negatively impact net returns in Douglas Fir regions and positively affect pine regions. Precipitation is linearly related to forest net returns, while temperature is not linearly related. With this finding, various areas of Oregon and Washington that are expected to experience heavier precipitation due to climate change should expect more net returns from their forestlands. Close

• 147. [Article] An exploration of microcombustor feasibility

  The goals of this research were first to examine flame quenching in tubing smaller than the quench diameter, and then to place lower size limits on microcombustor and microreactor systems by studying a ...

  Citation × Citation Citation Abstract Copy Title: An exploration of microcombustor feasibility Author: Hatfield, Jonathan M. The goals of this research were first to examine flame quenching in tubing smaller than the quench diameter, and then to place lower size limits on microcombustor and microreactor systems by studying a catalytic microcombustor burning propane. In the first set of experiments, flame quenching was examined as a function of wall temperature for various hydrocarbon fuels. This was accomplished by creating a wall temperature profile along a tube, allowing a flame to propagate down the tube, and measuring the temperature of the tube wall coincident with the flame front. This wall quench temperature was plotted as a function of both the equivalence ratio and tube diameter. Fuels tested included propane, hexane, kerosene and diesel. Results showed that quench diameter was reduced by elevating the wall temperature and that the quench temperature increased for increasing mixture flow velocities. Flames were produced in tubes down to 0.8 mm in diameter. In the second set of experiments, a catalyst was used in combination with fuel preheating to obtain a self-sustaining combustion reaction in a chamber approximately 0.25 mm³ in size. Propane was used in this experiment. Results demonstrated that a stable self-sustaining reaction can be obtained in the microscale regime and that reaction temperatures are on the order of 900°C. This research not only aided in the characterization of hydrocarbon combustion in small diameter channels but also showed promise for development of microcombustor systems. Title: An exploration of microcombustor feasibility Author: Hatfield, Jonathan M. The goals of this research were first to examine flame quenching in tubing smaller than the quench diameter, and then to place lower size limits on microcombustor and microreactor systems by studying a catalytic microcombustor burning propane. In the first set of experiments, flame quenching was examined as a function of wall temperature for various hydrocarbon fuels. This was accomplished by creating a wall temperature profile along a tube, allowing a flame to propagate down the tube, and measuring the temperature of the tube wall coincident with the flame front. This wall quench temperature was plotted as a function of both the equivalence ratio and tube diameter. Fuels tested included propane, hexane, kerosene and diesel. Results showed that quench diameter was reduced by elevating the wall temperature and that the quench temperature increased for increasing mixture flow velocities. Flames were produced in tubes down to 0.8 mm in diameter. In the second set of experiments, a catalyst was used in combination with fuel preheating to obtain a self-sustaining combustion reaction in a chamber approximately 0.25 mm³ in size. Propane was used in this experiment. Results demonstrated that a stable self-sustaining reaction can be obtained in the microscale regime and that reaction temperatures are on the order of 900°C. This research not only aided in the characterization of hydrocarbon combustion in small diameter channels but also showed promise for development of microcombustor systems. Close

• 148. [Article] A study of the thermal characteristics of x-ray tube housings

  The relationship of x-ray tube housing temperature to duty cycle was studied for a superficial therapy x-ray installation, a dental radiographic installation, and a rotating-anode medical diagnostic installation. ...

  Citation × Citation Citation Abstract Copy Title: A study of the thermal characteristics of x-ray tube housings Author: Stovall, John Walter The relationship of x-ray tube housing temperature to duty cycle was studied for a superficial therapy x-ray installation, a dental radiographic installation, and a rotating-anode medical diagnostic installation. Thermistors were used to measure the tube housing temperature at points selected to be representative of thermal conditions on the surface of the x-ray tube housing. Measurements were made for continuous operation and intermittent operation, for the beam directed horizontally, and for the beam directed vertically down. Maximum temperatures were observed on the uppermost surfaces of the tube housings and minimum temperatures were observed on the lower surfaces of the tube housings. The orientation of the tube housing was found in some cases to alter the maximum tube housing temperature. Theoretically, tube housing temperatures for continuous and intermittent operation should be the same, but some differences were observed. These differences between tube housing temperatures observed for continuous operation and those observed for intermittent operation were due to differences in the duty cycle ratings specified by the x-ray tube manufacturer for continuous and intermittent operation. Title: A study of the thermal characteristics of x-ray tube housings Author: Stovall, John Walter The relationship of x-ray tube housing temperature to duty cycle was studied for a superficial therapy x-ray installation, a dental radiographic installation, and a rotating-anode medical diagnostic installation. Thermistors were used to measure the tube housing temperature at points selected to be representative of thermal conditions on the surface of the x-ray tube housing. Measurements were made for continuous operation and intermittent operation, for the beam directed horizontally, and for the beam directed vertically down. Maximum temperatures were observed on the uppermost surfaces of the tube housings and minimum temperatures were observed on the lower surfaces of the tube housings. The orientation of the tube housing was found in some cases to alter the maximum tube housing temperature. Theoretically, tube housing temperatures for continuous and intermittent operation should be the same, but some differences were observed. These differences between tube housing temperatures observed for continuous operation and those observed for intermittent operation were due to differences in the duty cycle ratings specified by the x-ray tube manufacturer for continuous and intermittent operation. Close

• 149. [Article] Field-effect transistor noise at low temperatures

  Low temperature noise measurements on junction field-effect transistors tend to substantiate a theory of low frequency field-effect transistor noise based on the presence of generation centers in the gate-channel ...

  Citation × Citation Citation Abstract Copy Title: Field-effect transistor noise at low temperatures Author: Spaulding, Richard Alan Low temperature noise measurements on junction field-effect transistors tend to substantiate a theory of low frequency field-effect transistor noise based on the presence of generation centers in the gate-channel depletion region. Measurements of device noise voltage versus temperature reveal pronounced maxima and minima over the temperature range of 300° K to 77° K. Analysis of the maxima can yield information on time constants, capture cross-sections and energy levels of generation centers in the depletion region. The pertinent theories of junction FET noise are reviewed with regard to temperature-dependent phenomena. Contributions due to thermal noise, shot noise, induced gate noise, surface leakage and generation centers are considered. Techniques for measuring the temperature dependence of FET noise are discussed, and a practical approach is described. Measurements are made in a typical circuit configuration in order that the results may be directly related to device applications. Measured data on the temperature dependence of noise in the 300° K to 77°K range is presented for 14 n- and p-channel FET's. Salient features of the data are analyzed and correlated with theoretical predictions. Title: Field-effect transistor noise at low temperatures Author: Spaulding, Richard Alan Low temperature noise measurements on junction field-effect transistors tend to substantiate a theory of low frequency field-effect transistor noise based on the presence of generation centers in the gate-channel depletion region. Measurements of device noise voltage versus temperature reveal pronounced maxima and minima over the temperature range of 300° K to 77° K. Analysis of the maxima can yield information on time constants, capture cross-sections and energy levels of generation centers in the depletion region. The pertinent theories of junction FET noise are reviewed with regard to temperature-dependent phenomena. Contributions due to thermal noise, shot noise, induced gate noise, surface leakage and generation centers are considered. Techniques for measuring the temperature dependence of FET noise are discussed, and a practical approach is described. Measurements are made in a typical circuit configuration in order that the results may be directly related to device applications. Measured data on the temperature dependence of noise in the 300° K to 77°K range is presented for 14 n- and p-channel FET's. Salient features of the data are analyzed and correlated with theoretical predictions. Close

• 150. [Article] Temperature-effective periods during crossvein development in crossveinless-like strains of Drosophila melanogaster

  This investigation is concerned with the determination of the temperature-effective period (T.E.P.) for crossvein development at physiological temperatures using three isogenic crossveinlesslike (cvl) ...

  Citation × Citation Citation Abstract Copy Title: Temperature-effective periods during crossvein development in crossveinless-like strains of Drosophila melanogaster Author: Wong, Patrick Tin-Choi This investigation is concerned with the determination of the temperature-effective period (T.E.P.) for crossvein development at physiological temperatures using three isogenic crossveinlesslike (cvl) lines of Drosophila melanogaster. The method used to determine T.E.P. relies on temperature differences in phenotypes and on a program of transfers from one temperature to another at regular intervals during development. The T.E.P. in each cvl line occurs in the interval between one-eighth and one-quarter of pupal development. The onset of T.E.P. in each cvl line is fairly well determined. The end points are not obtained in some cases and are ambiguous in others. Therefore, the durations of the T.E.P.'s cannot be stated. One of the complications in defining T.E.P. is the "Switching effect", an effect on the phenotype due to transfer from one temperature to another. Though temperature, genotypic and sex differences in T.E.P. are evident in some cases, theoretical interpretation of their significances are limited by the several complications. Title: Temperature-effective periods during crossvein development in crossveinless-like strains of Drosophila melanogaster Author: Wong, Patrick Tin-Choi This investigation is concerned with the determination of the temperature-effective period (T.E.P.) for crossvein development at physiological temperatures using three isogenic crossveinlesslike (cvl) lines of Drosophila melanogaster. The method used to determine T.E.P. relies on temperature differences in phenotypes and on a program of transfers from one temperature to another at regular intervals during development. The T.E.P. in each cvl line occurs in the interval between one-eighth and one-quarter of pupal development. The onset of T.E.P. in each cvl line is fairly well determined. The end points are not obtained in some cases and are ambiguous in others. Therefore, the durations of the T.E.P.'s cannot be stated. One of the complications in defining T.E.P. is the "Switching effect", an effect on the phenotype due to transfer from one temperature to another. Though temperature, genotypic and sex differences in T.E.P. are evident in some cases, theoretical interpretation of their significances are limited by the several complications. Close