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• 2171. [Article] The occurrence of abscisic acid in the dormant shoots of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco]

  Methanolic extracts of the dormant Douglas-fir shoots (buds, leaves, and stems) were fractionated by solvent partitioning (sodium bicarbonate-diethyl ether). The acidic portion of the extract was subjected ...

  Citation × Citation Citation Abstract Copy Title: The occurrence of abscisic acid in the dormant shoots of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] Author: Webber, John Edinburgh Methanolic extracts of the dormant Douglas-fir shoots (buds, leaves, and stems) were fractionated by solvent partitioning (sodium bicarbonate-diethyl ether). The acidic portion of the extract was subjected to column (Sephadex LH-2O, Silica Gel and Polyvinylpyrrolidone), preparative thick-layer and gas-liquid chromatography. Fractions collected from chromatographic separations were collected and tested for biological activity by the standard straight-growth Avena bioassay. Three series of extracts, collected in 1969 (preliminary series), 1970-1971 (first series), and 1972 (second series) were analyzed. Results of the preliminary series (buds only) showed only the presence of growth inhibiting compounds. No growth promoters were observed. Analyses of the first series extracts (buds only) showed that the zones of maximum growth inhibition in column and preparative thick-layer chromatographic separations corresponded to the elution volumes and Rf values of abscisic acid. Preparative thick-layer and gas-liquid chromatography were used successfully to isolate abscisic acid from the extract. Confirmation of its presence was determined on the purified methylated (diazomethane) extract by mass spectrometry, conversion of abscisic acid into its C2-trans-isomer, and the positive results for specific color reaction. This is the first reported occurrence of abscisic acid in Douglas-fir. Abscisic acid was quantified in the remaining extracts of the first series. The occurrence of the C2-trans-isomer was not observed in any of the extracts. In the second series, abscisic acid in the dormant buds, leaves and stems was quantified. The results from this series showed high levels of abscisic acid in the buds (1.2 g/g fresh weight), leaves (0.347 g/g fresh weight), and stems (0.094 g/g fresh weight) for the fall collection (October 1972). All tissues showed the lowest levels of abscisic acid in early spring (February, March and April). Although the concentration of abs cisic acid was shown to follow the dormancy cycle in Douglas-fir, it appears to play a secondary role (if any)in the induction of dormancy in this species. The trend for abscisic acid concentration throughout the dormancy cycle appears to follow more closely the tree s capacity to biosynthe size the compound. One of the interfering compounds in the gas-liquid chromatographic analyses of abs cisic acid was determined by mass spectrometry and nuclear magnetic resonance to be dioctyl phthalate [di-(2-ethylhexyl)phthalate]. The natural occurrence of this phthalate ester in Douglas-fir is doubted and its presence was probably introduced as an artifact of the isolation procedure. The fact that it possessed inhibitory activity, however, stressed the importance for rigorous isolation procedures in abscisic acid analysis. Two other regions of growth inhibition were observed but no further chemical characterization was attempted. Title: The occurrence of abscisic acid in the dormant shoots of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] Author: Webber, John Edinburgh Methanolic extracts of the dormant Douglas-fir shoots (buds, leaves, and stems) were fractionated by solvent partitioning (sodium bicarbonate-diethyl ether). The acidic portion of the extract was subjected to column (Sephadex LH-2O, Silica Gel and Polyvinylpyrrolidone), preparative thick-layer and gas-liquid chromatography. Fractions collected from chromatographic separations were collected and tested for biological activity by the standard straight-growth Avena bioassay. Three series of extracts, collected in 1969 (preliminary series), 1970-1971 (first series), and 1972 (second series) were analyzed. Results of the preliminary series (buds only) showed only the presence of growth inhibiting compounds. No growth promoters were observed. Analyses of the first series extracts (buds only) showed that the zones of maximum growth inhibition in column and preparative thick-layer chromatographic separations corresponded to the elution volumes and Rf values of abscisic acid. Preparative thick-layer and gas-liquid chromatography were used successfully to isolate abscisic acid from the extract. Confirmation of its presence was determined on the purified methylated (diazomethane) extract by mass spectrometry, conversion of abscisic acid into its C2-trans-isomer, and the positive results for specific color reaction. This is the first reported occurrence of abscisic acid in Douglas-fir. Abscisic acid was quantified in the remaining extracts of the first series. The occurrence of the C2-trans-isomer was not observed in any of the extracts. In the second series, abscisic acid in the dormant buds, leaves and stems was quantified. The results from this series showed high levels of abscisic acid in the buds (1.2 g/g fresh weight), leaves (0.347 g/g fresh weight), and stems (0.094 g/g fresh weight) for the fall collection (October 1972). All tissues showed the lowest levels of abscisic acid in early spring (February, March and April). Although the concentration of abs cisic acid was shown to follow the dormancy cycle in Douglas-fir, it appears to play a secondary role (if any)in the induction of dormancy in this species. The trend for abscisic acid concentration throughout the dormancy cycle appears to follow more closely the tree s capacity to biosynthe size the compound. One of the interfering compounds in the gas-liquid chromatographic analyses of abs cisic acid was determined by mass spectrometry and nuclear magnetic resonance to be dioctyl phthalate [di-(2-ethylhexyl)phthalate]. The natural occurrence of this phthalate ester in Douglas-fir is doubted and its presence was probably introduced as an artifact of the isolation procedure. The fact that it possessed inhibitory activity, however, stressed the importance for rigorous isolation procedures in abscisic acid analysis. Two other regions of growth inhibition were observed but no further chemical characterization was attempted. Close

• 2172. [Article] Carbon fluxes across three climatically-distinct forest chronosequences in Oregon

  Biometric and gas exchange techniques were used to measure soil respiration (soil surface CO₂ efflux) and NEP (Net Ecosystem Production) across three climatically-distinct forest chronosequences in Oregon. Results ...

  Citation × Citation Citation Abstract Copy Title: Carbon fluxes across three climatically-distinct forest chronosequences in Oregon Author: Campbell, John Biometric and gas exchange techniques were used to measure soil respiration (soil surface CO₂ efflux) and NEP (Net Ecosystem Production) across three climatically-distinct forest chronosequences in Oregon. Results indicate significant forest type, age, and forest type x age interaction effects on annual soil respiration. A regional age class distribution skewed away from the youngest and oldest forests moderate regional variation in soil respiration. Sensitivity analysis suggests that the regional variation in annual soil respiration is most dependent on summer base rates (i.e. soil respiration normalized to a common temperature) and much less dependent on site-specific temperature response curve (to which annual rates are relatively insensitive) and soil degree-days (which vary only 10% among sites). Across all plots, annual soil respiration was not correlated with aboveground net primary production (ANPP, R²=O.06, p>0.1) but it was correlated with belowground net primary production (R²=0.43, p<0.001). Despite the wide range in temperature and precipitation regimes experienced by these forests, all exhibited similar soil respiration per unit fine root biomass, (R²=0.45, p<0.00l). Forest floor mass and mineral soil carbon were only weakly coupled to soil respiration (R²=0.14, and 0.12, respectively). Trends between soil respiration, production, and root mass among age classes within cover type were inconsistent and do not always reflect cross-site trends. NEP was highly negative immediately following stand replacing disturbance in all forests and recovered to positive values by 10, 20, and 30 years of age for the mild and mesic Coast Range, West Cascades and East Cascades, respectively. The response of stand-level NEP to individual disturbance events is greater than that attributable to edaphoclimatic differences between forest type. However, when successional trends in NEP are weighted by current age class distributions, the variability in landscape-level NEP attributable to whole disturbance regimes is equivalent to that attributable regional edaphoclimatic differences between forest types. Simulations of age class distribution under varying disturbance frequencies suggest that the sensitivity of landscape-level NEP to changes in disturbance regime varies among forest types and is linked to both remnant detritus and photosynthetic recovery rate that are partly a function of long-term edaphoclimatic differences. Title: Carbon fluxes across three climatically-distinct forest chronosequences in Oregon Author: Campbell, John Biometric and gas exchange techniques were used to measure soil respiration (soil surface CO₂ efflux) and NEP (Net Ecosystem Production) across three climatically-distinct forest chronosequences in Oregon. Results indicate significant forest type, age, and forest type x age interaction effects on annual soil respiration. A regional age class distribution skewed away from the youngest and oldest forests moderate regional variation in soil respiration. Sensitivity analysis suggests that the regional variation in annual soil respiration is most dependent on summer base rates (i.e. soil respiration normalized to a common temperature) and much less dependent on site-specific temperature response curve (to which annual rates are relatively insensitive) and soil degree-days (which vary only 10% among sites). Across all plots, annual soil respiration was not correlated with aboveground net primary production (ANPP, R²=O.06, p>0.1) but it was correlated with belowground net primary production (R²=0.43, p<0.001). Despite the wide range in temperature and precipitation regimes experienced by these forests, all exhibited similar soil respiration per unit fine root biomass, (R²=0.45, p<0.00l). Forest floor mass and mineral soil carbon were only weakly coupled to soil respiration (R²=0.14, and 0.12, respectively). Trends between soil respiration, production, and root mass among age classes within cover type were inconsistent and do not always reflect cross-site trends. NEP was highly negative immediately following stand replacing disturbance in all forests and recovered to positive values by 10, 20, and 30 years of age for the mild and mesic Coast Range, West Cascades and East Cascades, respectively. The response of stand-level NEP to individual disturbance events is greater than that attributable to edaphoclimatic differences between forest type. However, when successional trends in NEP are weighted by current age class distributions, the variability in landscape-level NEP attributable to whole disturbance regimes is equivalent to that attributable regional edaphoclimatic differences between forest types. Simulations of age class distribution under varying disturbance frequencies suggest that the sensitivity of landscape-level NEP to changes in disturbance regime varies among forest types and is linked to both remnant detritus and photosynthetic recovery rate that are partly a function of long-term edaphoclimatic differences. Close

• 2173. [Article] Stratigraphic correlation of seismoturbidites and the integration of sediment cores with 3.5 kHz chirp subbottom data in southern Cascadia

  In order to evaluate the shallow stratigraphy along the southern Cascadia abyssal margin and northern California abyssal plain, CHIRP subbottom profiles capable of imaging individual turbidite beds in ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphic correlation of seismoturbidites and the integration of sediment cores with 3.5 kHz chirp subbottom data in southern Cascadia Author: Black, Bran In order to evaluate the shallow stratigraphy along the southern Cascadia abyssal margin and northern California abyssal plain, CHIRP subbottom profiles capable of imaging individual turbidite beds in the upper tens of meters of the subsurface were collected. Reflectors imaged with the 3.5 kHz CHIRP subbottom data represent turbidite beds within the first 20-30 m of seafloor sediments that have sufficient impedance contrast and are separated by at least 20 cm vertically. Correlation of subbottom reflectors along both margins, constrained by core data at numerous sites along strike, revealed that many of these reflectors were contiguous over distances of hundreds of kilometers in southern Cascadia. The placement of subbottom reflectors coincided strongly with the configuration of many of the turbidite beds identified in nearby cores. A number of thin, low density beds evident in the cores are not imaged in the subbottom data in the northern part of the study area near Rogue Canyon, but become more robust southward where some are imaged as reflectors in the subbottom data. The independently derived core and subbottom based correlations of beds in southern Cascadia were found to be in fairly close agreement, and collectively support the continuity of beds over significant distances of up to 200 km along strike. Robustness of the beds between Trinidad and Rogue Canyons does not appear to be related to proximity to canyon mouths, suggesting that these beds and their transport are not exclusively related to canyon sources. The combined core and reflection data and the continuity of beds support a seismogenic source for Holocene beds correlated over long distances owing to the broad areal extent and lack of strong linkage to canyon systems. Data from paleoseismic studies worldwide were compiled in an effort to parameterize the likely triggering distances associated with turbidity currents initiated by earthquakes on the CSZ and NSAF. These ranges are estimated at 60-120 km for the CSZ and 40-75 km for the NSAF. A similar approach using MMI values associated with earthquakes linked to seismoturbidites yielded a threshold estimate for northern California of ~ MMI 5.5. A region from between Eel Canyon and Mendocino Channel in the north to the area north of Noyo Canyon in the south was identified as having a higher likelihood for recording at least a portion past seismicity from both the NSAF and CSZ in local sediments. The high frequency of turbidite beds in southernmost Cascadia could be the result of Cascadia and NSAF seismicity combined, though some input from hyperpycnal flows cannot be excluded. Further study of sediments in this zone may improve our understanding of potential stress triggering interactions between the CSZ and NSAF. Title: Stratigraphic correlation of seismoturbidites and the integration of sediment cores with 3.5 kHz chirp subbottom data in southern Cascadia Author: Black, Bran In order to evaluate the shallow stratigraphy along the southern Cascadia abyssal margin and northern California abyssal plain, CHIRP subbottom profiles capable of imaging individual turbidite beds in the upper tens of meters of the subsurface were collected. Reflectors imaged with the 3.5 kHz CHIRP subbottom data represent turbidite beds within the first 20-30 m of seafloor sediments that have sufficient impedance contrast and are separated by at least 20 cm vertically. Correlation of subbottom reflectors along both margins, constrained by core data at numerous sites along strike, revealed that many of these reflectors were contiguous over distances of hundreds of kilometers in southern Cascadia. The placement of subbottom reflectors coincided strongly with the configuration of many of the turbidite beds identified in nearby cores. A number of thin, low density beds evident in the cores are not imaged in the subbottom data in the northern part of the study area near Rogue Canyon, but become more robust southward where some are imaged as reflectors in the subbottom data. The independently derived core and subbottom based correlations of beds in southern Cascadia were found to be in fairly close agreement, and collectively support the continuity of beds over significant distances of up to 200 km along strike. Robustness of the beds between Trinidad and Rogue Canyons does not appear to be related to proximity to canyon mouths, suggesting that these beds and their transport are not exclusively related to canyon sources. The combined core and reflection data and the continuity of beds support a seismogenic source for Holocene beds correlated over long distances owing to the broad areal extent and lack of strong linkage to canyon systems. Data from paleoseismic studies worldwide were compiled in an effort to parameterize the likely triggering distances associated with turbidity currents initiated by earthquakes on the CSZ and NSAF. These ranges are estimated at 60-120 km for the CSZ and 40-75 km for the NSAF. A similar approach using MMI values associated with earthquakes linked to seismoturbidites yielded a threshold estimate for northern California of ~ MMI 5.5. A region from between Eel Canyon and Mendocino Channel in the north to the area north of Noyo Canyon in the south was identified as having a higher likelihood for recording at least a portion past seismicity from both the NSAF and CSZ in local sediments. The high frequency of turbidite beds in southernmost Cascadia could be the result of Cascadia and NSAF seismicity combined, though some input from hyperpycnal flows cannot be excluded. Further study of sediments in this zone may improve our understanding of potential stress triggering interactions between the CSZ and NSAF. Close

• 2174. [Article] Oregon klanswomen of the 1920s : a study of tribalism, gender, and women's power

  The fraternal order of the KKK, originally founded in the 1860s, reemerged in 1915, to present itself as an organization committed to the Cause - a dangerous reactionary political ideology to protect white, ...

  Citation × Citation Citation Abstract Copy Title: Oregon klanswomen of the 1920s : a study of tribalism, gender, and women's power Author: Rielly Thorson, Wendy P. The fraternal order of the KKK, originally founded in the 1860s, reemerged in 1915, to present itself as an organization committed to the Cause - a dangerous reactionary political ideology to protect white, native born, Protestant, middle class values from all outsiders. Concomitantly, the Ladies of the Invisible Empire (LOTIE5) and the Women's Ku Klux Klan (WKKK) were women who rallied to the Cause, by oppressing outsiders who were considered the real enemy that generated lies in order to bring the Klan down. Klan loyalty required patriotic pledges to America, religious pledges to Protestantism, and, importantly, moral pledges to protect the purity of manhood arid womanhood. As the 1920s Ku Klux Klan struggled with its own masculine ideology concerning the 'woman question' to determine Klanswomen's place within Klan culture, Oregon Klanswomen themselves redefined gender norms, challenged male hegemony, and acted in accordance with their own interpretation of their feminine roles as mothers and as citizens within the Klan. The focus of this thesis, then, is to understand how Oregon Klanswomen stretched normative gender boundaries within the patriarchal dominion of the Klan itself, and to understand their participation in the Ku Klux Klan in terms of their access to power and authority. As Klansmen defined women's power within the confines of gender normative boundaries, women took advantage of the power and authority given to them to create and self define themselves as a group. The emergence of Klanswomen forming identifiable tribal groups such as the LOTIEs and the WKKK emanated from the highly masculinized fraternal group of the KKK. These women led other white Protestant women into a campaign against outsiders including other women. Klansmen may have set the gender boundaries to restrict Klanswomen under their power, only to have the women undermine male Klan authority and redefine the gender norms themselves. Women do not always agree with societal dictation of their roles as women, and when a tribal group such as the Oregon LOTIEs grew in political autonomy, male hegemony was militantly challenged. Hence, Oregon Klanswomen were not invisible, nor were they influencing politics from their homes, instead they played several important political roles within the Klan. Whether women hid KKK terrorism by bringing normalcy to the campaign, acted as hostesses at events, or contributed financially, they exemplified autonomy and fierce tribalism as women within the Ku Klux Klan. Title: Oregon klanswomen of the 1920s : a study of tribalism, gender, and women's power Author: Rielly Thorson, Wendy P. The fraternal order of the KKK, originally founded in the 1860s, reemerged in 1915, to present itself as an organization committed to the Cause - a dangerous reactionary political ideology to protect white, native born, Protestant, middle class values from all outsiders. Concomitantly, the Ladies of the Invisible Empire (LOTIE5) and the Women's Ku Klux Klan (WKKK) were women who rallied to the Cause, by oppressing outsiders who were considered the real enemy that generated lies in order to bring the Klan down. Klan loyalty required patriotic pledges to America, religious pledges to Protestantism, and, importantly, moral pledges to protect the purity of manhood arid womanhood. As the 1920s Ku Klux Klan struggled with its own masculine ideology concerning the 'woman question' to determine Klanswomen's place within Klan culture, Oregon Klanswomen themselves redefined gender norms, challenged male hegemony, and acted in accordance with their own interpretation of their feminine roles as mothers and as citizens within the Klan. The focus of this thesis, then, is to understand how Oregon Klanswomen stretched normative gender boundaries within the patriarchal dominion of the Klan itself, and to understand their participation in the Ku Klux Klan in terms of their access to power and authority. As Klansmen defined women's power within the confines of gender normative boundaries, women took advantage of the power and authority given to them to create and self define themselves as a group. The emergence of Klanswomen forming identifiable tribal groups such as the LOTIEs and the WKKK emanated from the highly masculinized fraternal group of the KKK. These women led other white Protestant women into a campaign against outsiders including other women. Klansmen may have set the gender boundaries to restrict Klanswomen under their power, only to have the women undermine male Klan authority and redefine the gender norms themselves. Women do not always agree with societal dictation of their roles as women, and when a tribal group such as the Oregon LOTIEs grew in political autonomy, male hegemony was militantly challenged. Hence, Oregon Klanswomen were not invisible, nor were they influencing politics from their homes, instead they played several important political roles within the Klan. Whether women hid KKK terrorism by bringing normalcy to the campaign, acted as hostesses at events, or contributed financially, they exemplified autonomy and fierce tribalism as women within the Ku Klux Klan. Close

• 2175. [Article] The changing glaciers of Mt. Hood, Oregon and Mt. Rainier, Washington : implications for periglacial debris flows

  Mountain glaciers are receding worldwide with numerous consequences including changing hydrology and geomorphology. This study focuses on changes in glacier area on Mt. Hood, Oregon and Mt. Rainier, Washington ...

  Citation × Citation Citation Abstract Copy Title: The changing glaciers of Mt. Hood, Oregon and Mt. Rainier, Washington : implications for periglacial debris flows Author: Ellinger, Jonathan R. Mountain glaciers are receding worldwide with numerous consequences including changing hydrology and geomorphology. This study focuses on changes in glacier area on Mt. Hood, Oregon and Mt. Rainier, Washington where damaging debris flows have occurred in glaciated basins. Landsat imagery is used to map debris-free ice on a decadal time scale from 1987 to 2005. Debris-free glacier ice is clearly delineated using a ratio of Landsat spectral bands in the near-infrared part of the spectrum (bands 4 & 5). Landsat scenes were chosen during the months of September and October to minimize snow cover left over from the accumulation season and maximize exposure of debris-free glacial ice. SNOTEL data were also used to find the lowest snow year for each decade to minimize the potential of misclassifying remnant snow as glacial ice. Changes in debris-free ice are mapped to produce the most up-to-date rates of glacier retreat. Average glacial slopes, derived from airborne LiDAR data are used to compute slope corrected debris-free ice areas for all glaciers. A threshold value for the Landsat NDGI scenes was selected based on threshold testing on the Eliot and Reid glaciers on Mt. Hood. Contradicting earlier studies that say the glaciers on Mt. Hood are receding faster than the glaciers on Mt. Rainier, results show that from 1987 to 2005 Mt. Rainier and Mt. Hood lost similar amounts of debris-free ice extent at 14.0% and 13.9%, respectively. For both Mt. Hood and Mt. Rainier the change in slope corrected debris-free ice area was greater than that of the projected area change due to the steep slopes of both mountains. For Mt. Rainier an increase in recession rate was shown from 1992-2005 compared to 1987-1992 while on Mt. Hood the opposite is seen. On Mt. Rainier it was found that highly fragmented glaciers at lower elevations such as the Inter, Pyramid, and the Van Trump Glaciers lost the highest percent of their original 1987 ice extent and were also shown to be associated with new debris flows in 2006. On Mt. Hood none of the 2006 debris flows initiated within zones of recent glacial recession, however, all debris flows from 2006 originated from streams with a direct connection to glaciers. The Newton Clark Glacier, having lost the most coverage of debris-free ice from 1987 to 2005, is also associated with the highest number of debris-flows in its drainage since 1980. Precipitation data for both mountains show no trend but there was a statistically significant increase in summer air temperature at Mt. Hood over the period 1984-2009. This study suggests that glaciers may play a role in the location of initiation sites, of debris flows, but there is not enough evidence to argue that glacier recession is responsible for producing debris flows. Title: The changing glaciers of Mt. Hood, Oregon and Mt. Rainier, Washington : implications for periglacial debris flows Author: Ellinger, Jonathan R. Mountain glaciers are receding worldwide with numerous consequences including changing hydrology and geomorphology. This study focuses on changes in glacier area on Mt. Hood, Oregon and Mt. Rainier, Washington where damaging debris flows have occurred in glaciated basins. Landsat imagery is used to map debris-free ice on a decadal time scale from 1987 to 2005. Debris-free glacier ice is clearly delineated using a ratio of Landsat spectral bands in the near-infrared part of the spectrum (bands 4 & 5). Landsat scenes were chosen during the months of September and October to minimize snow cover left over from the accumulation season and maximize exposure of debris-free glacial ice. SNOTEL data were also used to find the lowest snow year for each decade to minimize the potential of misclassifying remnant snow as glacial ice. Changes in debris-free ice are mapped to produce the most up-to-date rates of glacier retreat. Average glacial slopes, derived from airborne LiDAR data are used to compute slope corrected debris-free ice areas for all glaciers. A threshold value for the Landsat NDGI scenes was selected based on threshold testing on the Eliot and Reid glaciers on Mt. Hood. Contradicting earlier studies that say the glaciers on Mt. Hood are receding faster than the glaciers on Mt. Rainier, results show that from 1987 to 2005 Mt. Rainier and Mt. Hood lost similar amounts of debris-free ice extent at 14.0% and 13.9%, respectively. For both Mt. Hood and Mt. Rainier the change in slope corrected debris-free ice area was greater than that of the projected area change due to the steep slopes of both mountains. For Mt. Rainier an increase in recession rate was shown from 1992-2005 compared to 1987-1992 while on Mt. Hood the opposite is seen. On Mt. Rainier it was found that highly fragmented glaciers at lower elevations such as the Inter, Pyramid, and the Van Trump Glaciers lost the highest percent of their original 1987 ice extent and were also shown to be associated with new debris flows in 2006. On Mt. Hood none of the 2006 debris flows initiated within zones of recent glacial recession, however, all debris flows from 2006 originated from streams with a direct connection to glaciers. The Newton Clark Glacier, having lost the most coverage of debris-free ice from 1987 to 2005, is also associated with the highest number of debris-flows in its drainage since 1980. Precipitation data for both mountains show no trend but there was a statistically significant increase in summer air temperature at Mt. Hood over the period 1984-2009. This study suggests that glaciers may play a role in the location of initiation sites, of debris flows, but there is not enough evidence to argue that glacier recession is responsible for producing debris flows. Close

• 2176. [Article] Indoor cycling wear : a needs assessment

  As designer it is important to understand the needs and wants of the consumer. In sportswear design it is particularly important to know what consumers think they want and what are the physical movements ...

  Citation × Citation Citation Abstract Copy Title: Indoor cycling wear : a needs assessment Author: Ho, Yi-Ling As designer it is important to understand the needs and wants of the consumer. In sportswear design it is particularly important to know what consumers think they want and what are the physical movements needs which the apparel must meet. This study was developed to provide the researcher with a foundation in designing sportswear for particular sports. Indoor cycling was selected because of the popularity of the activity and the lack of specific apparel. Though indoor cycling is viewed as substitute for road cycling, the conditions and participants are not the same. This study uses a design process which asks the consumer about their aesthetic needs of the clothing as well as the functional needs. The purpose of this study is to identify needs related to indoor cycling wear design and to examine commitment differences in clothing attributes selection. Data was gathered as to the preferences of indoor cyclists for garment characteristics of ideal indoor cycling wear. A questionnaire was developed as the instrument that would be used to gather the indoor cyclists' preferences. The goal is to establish design criteria of indoor cycling wear that meets the needs of highly committed and casual indoor cyclists. Each questionnaire was made up of three major parts: (1)Demographics (2) Personal value statements and(3) Indoor cycling wear design preferences. The 137 questionnaires were analyzed to test the hypotheses and investigate the clothing needs of indoor cyclists who were involved with indoor cycling class. The respondents for this study were a sample of 135 (85 females and 50 males) participants. Demographic data analysis showed that most of the respondents were between 46 to 60 years. The majority of the participants reported the length of participation in indoor cycling class was above 3 years and amount of time spent for indoor cycling class was 2 to 3 times a week. Over 75% of the respondents were not only attending indoor cycling class but also enjoyed in outdoor cycling for exercise. In this study, frequencies were used to identify the design criteria for males and females indoor cycling design. The indoor cycling clothing design criteria were combined and composite drawings of indoor cycling wear preferences were developed. It was not an objective of this research to develop prototypes from the design criteria. However, the reported design criteria could be used as guidelines for the development of future indoor cycling clothing. Though it is not an original objective of the study, this research also indicates that an older consumer may have different athletic clothing needs and should be a topic for future research. Title: Indoor cycling wear : a needs assessment Author: Ho, Yi-Ling As designer it is important to understand the needs and wants of the consumer. In sportswear design it is particularly important to know what consumers think they want and what are the physical movements needs which the apparel must meet. This study was developed to provide the researcher with a foundation in designing sportswear for particular sports. Indoor cycling was selected because of the popularity of the activity and the lack of specific apparel. Though indoor cycling is viewed as substitute for road cycling, the conditions and participants are not the same. This study uses a design process which asks the consumer about their aesthetic needs of the clothing as well as the functional needs. The purpose of this study is to identify needs related to indoor cycling wear design and to examine commitment differences in clothing attributes selection. Data was gathered as to the preferences of indoor cyclists for garment characteristics of ideal indoor cycling wear. A questionnaire was developed as the instrument that would be used to gather the indoor cyclists' preferences. The goal is to establish design criteria of indoor cycling wear that meets the needs of highly committed and casual indoor cyclists. Each questionnaire was made up of three major parts: (1)Demographics (2) Personal value statements and(3) Indoor cycling wear design preferences. The 137 questionnaires were analyzed to test the hypotheses and investigate the clothing needs of indoor cyclists who were involved with indoor cycling class. The respondents for this study were a sample of 135 (85 females and 50 males) participants. Demographic data analysis showed that most of the respondents were between 46 to 60 years. The majority of the participants reported the length of participation in indoor cycling class was above 3 years and amount of time spent for indoor cycling class was 2 to 3 times a week. Over 75% of the respondents were not only attending indoor cycling class but also enjoyed in outdoor cycling for exercise. In this study, frequencies were used to identify the design criteria for males and females indoor cycling design. The indoor cycling clothing design criteria were combined and composite drawings of indoor cycling wear preferences were developed. It was not an objective of this research to develop prototypes from the design criteria. However, the reported design criteria could be used as guidelines for the development of future indoor cycling clothing. Though it is not an original objective of the study, this research also indicates that an older consumer may have different athletic clothing needs and should be a topic for future research. Close

• 2177. [Article] Development of a guideline for estimating tsunami forces on bridge superstructures

  Infrastructures along the Oregon Coast are vulnerable to seismic events in the Cascadia Subduction Zone that could generate large tsunamis. Bridges along the coast are an important part of the transportation ...

  Citation × Citation Citation Abstract Copy Title: Development of a guideline for estimating tsunami forces on bridge superstructures Author: Boon-intra, Sutaporn Infrastructures along the Oregon Coast are vulnerable to seismic events in the Cascadia Subduction Zone that could generate large tsunamis. Bridges along the coast are an important part of the transportation and lifeline system in the area. The major damages on these bridges due to earthquake and/or tsunami would result in traffic disruption along the coast which in turn could significantly damage the economic in the region. Most of these bridges, built between the 1950's and 1970's, were not designed to withstand such large seismic and tsunami loads; thus, they are at risk of being damaged. Since specific design codes for tsunami impact on bridge superstructures are currently not available in general, and in the State of Oregon in particular, this thesis develops and presents a guideline for estimating tsunami forces on bridge superstructures along the Oregon Coast for practical use in engineering design. These guidelines are generally expected to be applicable in other locations under similar situations. In the development of the guideline, numerical models based on a finite-element code (LS-DYNA) were developed to analyze tsunami impact on full-scaled bridge superstructures of four selected bridges on the Oregon coast - Schooner Creek Bridge, Drift Creek Bridge, Millport Slough Bridge, and Siletz River Bridge. The numerical models were analyzed for a better understanding of the interaction between tsunamis and bridge superstructures and to calculate tsunami forces time-histories on the bridges. Two different types of bridge superstructure, deck-girder and box section, were developed in the case of the Schooner Creek Bridge to study the performance of both the cross-sectional configuration subjected to identical tsunami load conditions. The results showed that the tsunami forces on box section are significantly higher than the forces on deck-girder section; thus, the box section might not be appropriate to be used in a tsunami run-up zone. Moreover, numerical testing of bridge superstructures with rails and without rails under identical tsunami loads are performed to examine an effect of rails to tsunami forces. The results suggested that horizontal and vertical tsunami forces on bridge without rails is smaller than on bridge with rigid rails up to 20% and 15%, respectively. Furthermore, results obtained from the numerical models are incorporated into the mathematical formulations from the existing literature to develop a simplified method for estimating tsunami forces on bridge superstructures. Appropriate empirical coefficients for bridge superstructures under tsunami loads were evaluated in this study based on an average value of the scattering data from the numerical results. However, the guideline is intended to be used as a preliminary guidance for design only as it did not accounted for uncertainties, therefore, an appropriate factor of safety must be included in the design. A previous analysis of tsunami forces on the Spencer Creek Bridge on the Oregon Coast, also performed by the research group in which the author is a member, is revisited to examine the applicability of the developed guideline. This thesis also presents computational performance studies and an optimal number of CPUs for running fluid-structure interaction (FSI) numerical models of bridge superstructures using LS-DYNA software on high-performance computing (HPC) systems. Title: Development of a guideline for estimating tsunami forces on bridge superstructures Author: Boon-intra, Sutaporn Infrastructures along the Oregon Coast are vulnerable to seismic events in the Cascadia Subduction Zone that could generate large tsunamis. Bridges along the coast are an important part of the transportation and lifeline system in the area. The major damages on these bridges due to earthquake and/or tsunami would result in traffic disruption along the coast which in turn could significantly damage the economic in the region. Most of these bridges, built between the 1950's and 1970's, were not designed to withstand such large seismic and tsunami loads; thus, they are at risk of being damaged. Since specific design codes for tsunami impact on bridge superstructures are currently not available in general, and in the State of Oregon in particular, this thesis develops and presents a guideline for estimating tsunami forces on bridge superstructures along the Oregon Coast for practical use in engineering design. These guidelines are generally expected to be applicable in other locations under similar situations. In the development of the guideline, numerical models based on a finite-element code (LS-DYNA) were developed to analyze tsunami impact on full-scaled bridge superstructures of four selected bridges on the Oregon coast - Schooner Creek Bridge, Drift Creek Bridge, Millport Slough Bridge, and Siletz River Bridge. The numerical models were analyzed for a better understanding of the interaction between tsunamis and bridge superstructures and to calculate tsunami forces time-histories on the bridges. Two different types of bridge superstructure, deck-girder and box section, were developed in the case of the Schooner Creek Bridge to study the performance of both the cross-sectional configuration subjected to identical tsunami load conditions. The results showed that the tsunami forces on box section are significantly higher than the forces on deck-girder section; thus, the box section might not be appropriate to be used in a tsunami run-up zone. Moreover, numerical testing of bridge superstructures with rails and without rails under identical tsunami loads are performed to examine an effect of rails to tsunami forces. The results suggested that horizontal and vertical tsunami forces on bridge without rails is smaller than on bridge with rigid rails up to 20% and 15%, respectively. Furthermore, results obtained from the numerical models are incorporated into the mathematical formulations from the existing literature to develop a simplified method for estimating tsunami forces on bridge superstructures. Appropriate empirical coefficients for bridge superstructures under tsunami loads were evaluated in this study based on an average value of the scattering data from the numerical results. However, the guideline is intended to be used as a preliminary guidance for design only as it did not accounted for uncertainties, therefore, an appropriate factor of safety must be included in the design. A previous analysis of tsunami forces on the Spencer Creek Bridge on the Oregon Coast, also performed by the research group in which the author is a member, is revisited to examine the applicability of the developed guideline. This thesis also presents computational performance studies and an optimal number of CPUs for running fluid-structure interaction (FSI) numerical models of bridge superstructures using LS-DYNA software on high-performance computing (HPC) systems. Close

• 2178. [Article] Monte Carlo design and simulation of a shipboard ²⁵²Cf-based PGNAA analyzer for the sensitivity analysis of seafloor cores

  The seabed is envisaged to meet the increased future demands for minerals from the rapidly growing industrialized societies of the world. Shipboard analysis of cores can significantly reduce the cost and ...

  Citation × Citation Citation Abstract Copy Title: Monte Carlo design and simulation of a shipboard ²⁵²Cf-based PGNAA analyzer for the sensitivity analysis of seafloor cores Author: Anand, Ajay, 1961- The seabed is envisaged to meet the increased future demands for minerals from the rapidly growing industrialized societies of the world. Shipboard analysis of cores can significantly reduce the cost and time spent at the exploratory drilling stage by obviating the need to go back to land for analysis. It can further speed the exploration process by enabling a quick modification of the exploration plan based on the results of the shipboard analysis. A ²⁵²Cf-based analyzer utilizing the prompt gamma neutron activation analysis technique has been designed. The analyzer is a spherical iron shell with the source at its center. The seabed core is passed through a hollow composite tube which is positioned a short distance directly below the source and the resulting prompt gamma rays are collimated to a HPGe detector. The rest of the sphere is filled with paraffin. The gamma ray flux at the detector is converted into a count rate by using a semi-empirical detector response function. This count rate data are then used to determine the sensitivity and detection limits for the chosen elements (Mg, Al, Ti, Cr, Mn, Fe, Ni and Cu). Monte Carlo simulations using the Monte Carlo neutron photon coupled transport code, MCNP, were carried out for a parametric study of important variables influencing the design of the analyzer. These parameters included the moderator type, source to sample distance and sample porosity. MCNP was then used to model the analyzer and to generate the neutron flux profiles in the sample and the prompt gamma flux at the detector. Due to the non-availability of the prompt gamma data for most of the elements of economic interest in the ENDF/B-V cross section libraries associated with MCNP, the point kernel photon transport code ISOSHLD-II (modified for high energy gamma rays) was used to generate the gamma flux at the detector for specific elements. The ISOSHLD-II source term was calculated based on known gamma production data (thermal capture only) and the thermal neutron flux in the sample obtained from MCNP computations. The sensitivity and detection limits obtained from the isotopic source based analyzer were compared for the case of aluminum with values reported from reactor facilities. The results obtained indicate that the analyzer designed in this work could prove suitable for the on-line analysis of many elements of economic interest in seabed cores at the 1 weight percent level. Title: Monte Carlo design and simulation of a shipboard ²⁵²Cf-based PGNAA analyzer for the sensitivity analysis of seafloor cores Author: Anand, Ajay, 1961- The seabed is envisaged to meet the increased future demands for minerals from the rapidly growing industrialized societies of the world. Shipboard analysis of cores can significantly reduce the cost and time spent at the exploratory drilling stage by obviating the need to go back to land for analysis. It can further speed the exploration process by enabling a quick modification of the exploration plan based on the results of the shipboard analysis. A ²⁵²Cf-based analyzer utilizing the prompt gamma neutron activation analysis technique has been designed. The analyzer is a spherical iron shell with the source at its center. The seabed core is passed through a hollow composite tube which is positioned a short distance directly below the source and the resulting prompt gamma rays are collimated to a HPGe detector. The rest of the sphere is filled with paraffin. The gamma ray flux at the detector is converted into a count rate by using a semi-empirical detector response function. This count rate data are then used to determine the sensitivity and detection limits for the chosen elements (Mg, Al, Ti, Cr, Mn, Fe, Ni and Cu). Monte Carlo simulations using the Monte Carlo neutron photon coupled transport code, MCNP, were carried out for a parametric study of important variables influencing the design of the analyzer. These parameters included the moderator type, source to sample distance and sample porosity. MCNP was then used to model the analyzer and to generate the neutron flux profiles in the sample and the prompt gamma flux at the detector. Due to the non-availability of the prompt gamma data for most of the elements of economic interest in the ENDF/B-V cross section libraries associated with MCNP, the point kernel photon transport code ISOSHLD-II (modified for high energy gamma rays) was used to generate the gamma flux at the detector for specific elements. The ISOSHLD-II source term was calculated based on known gamma production data (thermal capture only) and the thermal neutron flux in the sample obtained from MCNP computations. The sensitivity and detection limits obtained from the isotopic source based analyzer were compared for the case of aluminum with values reported from reactor facilities. The results obtained indicate that the analyzer designed in this work could prove suitable for the on-line analysis of many elements of economic interest in seabed cores at the 1 weight percent level. Close

• 2179. [Article] Endocrinology of fur growth and reproduction in mink

  Experiments were conducted to determine: 1) the effects of exogenous melatonin and reduced photoperiod on molting and growth of the winter pelage (fur) and 2) whether changes in serum prolactin levels ...

  Citation × Citation Citation Abstract Copy Title: Endocrinology of fur growth and reproduction in mink Author: Rose, William Jackson Experiments were conducted to determine: 1) the effects of exogenous melatonin and reduced photoperiod on molting and growth of the winter pelage (fur) and 2) whether changes in serum prolactin levels of treated and control mink during this same period were correlated with growth of winter fur. Adult and kit female and male mink were utilized and treatments were initiated in late June. Regardless of sex or age, mink treated with 10 mg melatonin or a 6 hour light:18 hour dark photoperiod molted the summer pelage and attained prime winter pelage 6 weeks earlier than controls (P <.001). Both reduced photoperiod and exogenous melatonin caused serum prolactin concentrations to decline from a mean high of 5.9 ng/ml in mid-July to basal levels of less than 1.5 ng/ml by late July-early August, 6 to 8 weeks earlier than controls. These findings indicate that the photoperiodic effects on growth of the winter pelage of mink may be mediated through the pineal gland and its secretion of melatonin. These data also suggest that part of the mechanism of action of melatonin may be through the regulation of prolactin synthesis and secretion. Experiments were also designed to determine: 1) if prolactin receptors were present in the ovaries and uterus of the mink and 2) the relationship of changes in serum prolactin concentrations to levels of ovarian prolactin receptors during embryonic diapause. Concentrations of uterine and ovarian prolactin receptors of mink were quantified during 1) anestrus (uterus only), 2) when blastocysts were entering a state of diapause, and 3) during the period of blastocyst reactivation, just prior to implantation. Mink were also bled at periodic intervals during gestation and the serum levels of prolactin determined by use of radioimmunoassay. Scatchard analysis revealed a single class of binding sites for prolactin with K[subscript d] values of 8.25 x 10 [superscript -11] ± .68 M (uterus) and of 6.14 x 10 [superscript -11] ± .93 M (ovaries). The total concentration of uterine prolactin receptors during anestrus was 28 fmol/mg protein. The total concentration of ovarian receptors during anestrus was 90 fmol/mg protein, which increased significantly during embryonic diapause to 484 fmol/mg protein, and then declined to 16 fmol/mg protein during blastocyst reactivation. Serum prolactin concentrations began to increase soon after the vernal equinox (March 21) and were significantly elevated by March 27. The results of these studies clearly establish that the ovaries and possibly the uterus of the mink are target organs for prolactin. Title: Endocrinology of fur growth and reproduction in mink Author: Rose, William Jackson Experiments were conducted to determine: 1) the effects of exogenous melatonin and reduced photoperiod on molting and growth of the winter pelage (fur) and 2) whether changes in serum prolactin levels of treated and control mink during this same period were correlated with growth of winter fur. Adult and kit female and male mink were utilized and treatments were initiated in late June. Regardless of sex or age, mink treated with 10 mg melatonin or a 6 hour light:18 hour dark photoperiod molted the summer pelage and attained prime winter pelage 6 weeks earlier than controls (P <.001). Both reduced photoperiod and exogenous melatonin caused serum prolactin concentrations to decline from a mean high of 5.9 ng/ml in mid-July to basal levels of less than 1.5 ng/ml by late July-early August, 6 to 8 weeks earlier than controls. These findings indicate that the photoperiodic effects on growth of the winter pelage of mink may be mediated through the pineal gland and its secretion of melatonin. These data also suggest that part of the mechanism of action of melatonin may be through the regulation of prolactin synthesis and secretion. Experiments were also designed to determine: 1) if prolactin receptors were present in the ovaries and uterus of the mink and 2) the relationship of changes in serum prolactin concentrations to levels of ovarian prolactin receptors during embryonic diapause. Concentrations of uterine and ovarian prolactin receptors of mink were quantified during 1) anestrus (uterus only), 2) when blastocysts were entering a state of diapause, and 3) during the period of blastocyst reactivation, just prior to implantation. Mink were also bled at periodic intervals during gestation and the serum levels of prolactin determined by use of radioimmunoassay. Scatchard analysis revealed a single class of binding sites for prolactin with K[subscript d] values of 8.25 x 10 [superscript -11] ± .68 M (uterus) and of 6.14 x 10 [superscript -11] ± .93 M (ovaries). The total concentration of uterine prolactin receptors during anestrus was 28 fmol/mg protein. The total concentration of ovarian receptors during anestrus was 90 fmol/mg protein, which increased significantly during embryonic diapause to 484 fmol/mg protein, and then declined to 16 fmol/mg protein during blastocyst reactivation. Serum prolactin concentrations began to increase soon after the vernal equinox (March 21) and were significantly elevated by March 27. The results of these studies clearly establish that the ovaries and possibly the uterus of the mink are target organs for prolactin. Close

• 2180. [Article] Determination of selected secondary and tertiary amine alkaloids in barley malt

  The malt alkaloids N-methyltyramine, N,N-dimethyltyramine (hordenine), N-methyl-3-aminomethylindole and N,N-dimethyl-3-aminomethylindole (gramine) are known precursors for N-nitrosamines. Analytical procedures ...

  Citation × Citation Citation Abstract Copy Title: Determination of selected secondary and tertiary amine alkaloids in barley malt Author: Poocharoen, Boonthong The malt alkaloids N-methyltyramine, N,N-dimethyltyramine (hordenine), N-methyl-3-aminomethylindole and N,N-dimethyl-3-aminomethylindole (gramine) are known precursors for N-nitrosamines. Analytical procedures were developed and applied to extract and quantify these alkaloids from malt, green malt, malt roots, and raw barley. A ground malt sample under nitrogen atmosphere was extracted with 5 percent concentrated ammonium hydroxide in methanol at room temperature for 24 hours. After purification, the extracted alkaloids were quantitated by reverse phase high performance liquid chromatography using both phosphate buffer and ion-pairing solvent systems. The recoveries obtained for the alkaloids listed were, respectively, 77.4, 92.0, 74.0 and 80.5 percent with detection limit of 0.2, 0.2, 0.1 and 0.1 μg/gm. Conformation of identity of each alkaloid was accomplished by TLC, UV, and MS. Twenty-three samples of kilned malts, five samples of green malts, ten samples of kilned malt roots, five samples of green malt roots, and ten raw barley samples, from a total of 11 varieties of Hordeum vulgare were analyzed for the alkaloids of interest. N-Methyltyramine was found in every sample from all sources with a mean and range, respectively, of 26.8 (15.7-48.5), 21.4 (11.6-37.5), 1959.8 (1358.4-2798.4), 1532.5 (962.3-2091.1) and 4.7 μg/gm (0.4-17.9 μg/gm) on a dry weight basis. The means and ranges for hordenine were, respectively, 28.1 (8.9-42.4), 21.2 (9.6-35.5), 4066.4 (2741.2-5180.1), 3363.3 (1956.2-4744.3) and 0.7 μg/gm (0.5-1.0 μg/gm). Gramine was found in only two barley malt varieties examined where kilned and green malts contained, respectively, mean values and ranges of 7.4 (4.9-10.0) and 6.0 μg/gm (4.7-7.3 μg/gm). N-Methyl-3-aminomethylindole was not detected in any of the samples examined. The results of this investigation indicated that the variety of barley affected alkaloid production during malting. The results also showed that the kilning step of the malting process increased the total amount of each alkaloid produced. Finally, room temperature nitrosation of five varieties of kilned and green malts, in which the contents of hordenine and gramine were known, was carried out with an excess of nitrite in acetic acid at pH 3.2 for 18 hours. The amounts of N-nitrosodimethylamine (NDMA) obtained from this nitrosation were far greater than the expected yields for NDMA from the hordenine and gramine present in the malts. The results strongly suggest that the alkaloids hordenine and gramine were not the only precursors for NDMA and that there must be additional precursors; dimethylamine was suggested as a possibility. Title: Determination of selected secondary and tertiary amine alkaloids in barley malt Author: Poocharoen, Boonthong The malt alkaloids N-methyltyramine, N,N-dimethyltyramine (hordenine), N-methyl-3-aminomethylindole and N,N-dimethyl-3-aminomethylindole (gramine) are known precursors for N-nitrosamines. Analytical procedures were developed and applied to extract and quantify these alkaloids from malt, green malt, malt roots, and raw barley. A ground malt sample under nitrogen atmosphere was extracted with 5 percent concentrated ammonium hydroxide in methanol at room temperature for 24 hours. After purification, the extracted alkaloids were quantitated by reverse phase high performance liquid chromatography using both phosphate buffer and ion-pairing solvent systems. The recoveries obtained for the alkaloids listed were, respectively, 77.4, 92.0, 74.0 and 80.5 percent with detection limit of 0.2, 0.2, 0.1 and 0.1 μg/gm. Conformation of identity of each alkaloid was accomplished by TLC, UV, and MS. Twenty-three samples of kilned malts, five samples of green malts, ten samples of kilned malt roots, five samples of green malt roots, and ten raw barley samples, from a total of 11 varieties of Hordeum vulgare were analyzed for the alkaloids of interest. N-Methyltyramine was found in every sample from all sources with a mean and range, respectively, of 26.8 (15.7-48.5), 21.4 (11.6-37.5), 1959.8 (1358.4-2798.4), 1532.5 (962.3-2091.1) and 4.7 μg/gm (0.4-17.9 μg/gm) on a dry weight basis. The means and ranges for hordenine were, respectively, 28.1 (8.9-42.4), 21.2 (9.6-35.5), 4066.4 (2741.2-5180.1), 3363.3 (1956.2-4744.3) and 0.7 μg/gm (0.5-1.0 μg/gm). Gramine was found in only two barley malt varieties examined where kilned and green malts contained, respectively, mean values and ranges of 7.4 (4.9-10.0) and 6.0 μg/gm (4.7-7.3 μg/gm). N-Methyl-3-aminomethylindole was not detected in any of the samples examined. The results of this investigation indicated that the variety of barley affected alkaloid production during malting. The results also showed that the kilning step of the malting process increased the total amount of each alkaloid produced. Finally, room temperature nitrosation of five varieties of kilned and green malts, in which the contents of hordenine and gramine were known, was carried out with an excess of nitrite in acetic acid at pH 3.2 for 18 hours. The amounts of N-nitrosodimethylamine (NDMA) obtained from this nitrosation were far greater than the expected yields for NDMA from the hordenine and gramine present in the malts. The results strongly suggest that the alkaloids hordenine and gramine were not the only precursors for NDMA and that there must be additional precursors; dimethylamine was suggested as a possibility. Close