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• 1421. [Article] An Evaluation of a Graduate Social Work Training Program at John Adams High School

  This research study is an evaluation of a graduate social work training program funded by NIMH of the Department of Health, Education, and Welfare entitled "Teaching-Trainingship Grant in School Social ...

  Citation × Citation Citation Abstract Copy Title: An Evaluation of a Graduate Social Work Training Program at John Adams High School Author: Hall, George E., Lutz, Guy H. Year: 1973 This research study is an evaluation of a graduate social work training program funded by NIMH of the Department of Health, Education, and Welfare entitled "Teaching-Trainingship Grant in School Social Work." This grant provides training opportunities in a field placement at John Adams High School in Portland, Oregon, for Portland State University School of Social Work Masters degree candidates. Originally approved in June 1969, the grant became operational for the school year 1970-71. In addition to faculty salaries, supplies, professional consu1tation, fees, etc. the grant provides trainee stipends for selected students participating in the program. Both first and second year students in the graduate program are eligible for field placement at John Adams High School where they spend two days per week as school social work trainees. The unit is currently instucted by an MSW social worker who is a faculty member of the School of Social Work at Portland State University. The instructor provides a variety of training experiences for students including direct services to clients and families, supervision, consultation, program development, teaching and research. The primary focus of this study is to evaluate the effectiveness of the training program. at Adams High School. Secondarily, this study will attempt to answer three basic questions: Can a graduate school social work field instruction program in public school social work on the elementary and secondary levels be evaluated? Can an ongoing instrument be developed allowing for evaluation of program and individual instruction? Can the study provide analytical data for the program director's evaluation of the effectiveness of his training? This study was undertaken by the authors because of an interest in program evaluation as an integral function of professional social work practice. We feel agencies, particularly those financed through public funds are increasingly being pressured to not only quantify, but to qualify program effectiveness. Funding bodies now require evaluative research documenting direction and effectiveness of social programs. Findings of this study should be of value not only to the funding source and the program director, but also to other students who in the future may wish to conduct similar studies in evaluation of graduate social work field instruction. The following chapter discusses the background and development of John Adams High School and the educational climate that made possible the inclusion of this training program as a part of the learning experiences offered. Chapter III deals with the objectives of the training program. Chapter IV examines evaluative research. Chapter V develops the methodology of the research. The charts and statistics used are examined in Chapter VI. The data are presented and analyzed in Chapter VII. Summary, conclusions and recommendations are then set forth in the final chapter. Title: An Evaluation of a Graduate Social Work Training Program at John Adams High School Author: Hall, George E., Lutz, Guy H. Year: 1973 This research study is an evaluation of a graduate social work training program funded by NIMH of the Department of Health, Education, and Welfare entitled "Teaching-Trainingship Grant in School Social Work." This grant provides training opportunities in a field placement at John Adams High School in Portland, Oregon, for Portland State University School of Social Work Masters degree candidates. Originally approved in June 1969, the grant became operational for the school year 1970-71. In addition to faculty salaries, supplies, professional consu1tation, fees, etc. the grant provides trainee stipends for selected students participating in the program. Both first and second year students in the graduate program are eligible for field placement at John Adams High School where they spend two days per week as school social work trainees. The unit is currently instucted by an MSW social worker who is a faculty member of the School of Social Work at Portland State University. The instructor provides a variety of training experiences for students including direct services to clients and families, supervision, consultation, program development, teaching and research. The primary focus of this study is to evaluate the effectiveness of the training program. at Adams High School. Secondarily, this study will attempt to answer three basic questions: Can a graduate school social work field instruction program in public school social work on the elementary and secondary levels be evaluated? Can an ongoing instrument be developed allowing for evaluation of program and individual instruction? Can the study provide analytical data for the program director's evaluation of the effectiveness of his training? This study was undertaken by the authors because of an interest in program evaluation as an integral function of professional social work practice. We feel agencies, particularly those financed through public funds are increasingly being pressured to not only quantify, but to qualify program effectiveness. Funding bodies now require evaluative research documenting direction and effectiveness of social programs. Findings of this study should be of value not only to the funding source and the program director, but also to other students who in the future may wish to conduct similar studies in evaluation of graduate social work field instruction. The following chapter discusses the background and development of John Adams High School and the educational climate that made possible the inclusion of this training program as a part of the learning experiences offered. Chapter III deals with the objectives of the training program. Chapter IV examines evaluative research. Chapter V develops the methodology of the research. The charts and statistics used are examined in Chapter VI. The data are presented and analyzed in Chapter VII. Summary, conclusions and recommendations are then set forth in the final chapter. Close

• 1422. [Article] OSMB AIS Funds Final Report: Task 1 Boat Ramp Monitoring for New Zealand Mud Snails

  The New Zealand mud snail (Potamopyrgus antipodarum; NZMS) is an invasive species found in a variety of ecosystems in Oregon, including brackish estuaries, heavily used recreational rivers, and highly ...

  Citation × Citation Citation Abstract Copy Title: OSMB AIS Funds Final Report: Task 1 Boat Ramp Monitoring for New Zealand Mud Snails Author: Brenneis, Valance, Cimino, Samuel, Strecker, Angela L. Year: 2013 The New Zealand mud snail (Potamopyrgus antipodarum; NZMS) is an invasive species found in a variety of ecosystems in Oregon, including brackish estuaries, heavily used recreational rivers, and highly trafficked coastal freshwater lakes. NZMS are an invasive species of concern because once established, they may out-compete native invertebrate grazers, such as native insect larvae that provide important food resources for fish, and NZMS themselves provide little nutritional value. Monitoring for the presence and population density of NZMS was performed at boat ramps located along several water bodies in 2006 – 2007. These water bodies were then re-sampled during the summer of 2012 and winter of 2013 to investigate changes in population densities, as well as the potential spread of NZMS. In addition, six brackish estuaries and six freshwater coastal lakes were sampled in the summer of 2013 once again for population densities but also for stable isotope analysis to better understand the influence NZMS may have on these different ecosystem food webs. This work addresses how NZMS densities differ across invaded sites, how densities vary over time, how community diversity in rivers and estuaries varies between sites and over time, whether there is a correlation between NZMS densities and invertebrate diversity, and whether NZMS density correlates with decreasing dietary specificity for competing benthic invertebrates. Samples were sorted, identified, and counted, and stable isotope analyses from the summer 2013 field season were conducted on macroinvertebrates, zooplankton, and primary producers at the UC Davis Stable Isotope Facility. NZMS densities were found to be dynamic, with population densities increasing and decreasing over time and space. Additionally, two waterbodies (the lower Siuslaw River and the Nestucca River Estuary) previously without reported NZMS presence were identified to have established NZMS populations. Across invaded sites during the 2006 and 2012 sampling periods, there was a strong negative correlation between NZMS density and the diversity of the benthic invertebrate community. Within sites, no significant correlation was detected. High NZMS population densities were found to have a significantly negative relationship with detritivore density populations in the freshwater lake sites sampled in the summer of 2013. There were no significant relationships between NZMS and the density of any particular macroinvertebrate feeding habit group in estuaries. Additionally, stable isotope analyses indicated that NZMS at high population densities in the freshwater lakes share a similar stable isotope signature with macroinvertebrate herbivores, but NZMS had a more specific or narrow dietary range suggesting macroinvertebrate herbivores had more generalized diets than NZMS when at high densities. Conversely, NZMS population densities in the brackish estuary ecosystems showed no discernable patterns from the stable isotope analyses to indicate that their presence, either at high or low density, had an effect on the estuarine food webs. We concluded that continued research on long term population dynamics of invasive species like NZMS and their effects on native food webs remain crucial to future management and mitigation. Title: OSMB AIS Funds Final Report: Task 1 Boat Ramp Monitoring for New Zealand Mud Snails Author: Brenneis, Valance, Cimino, Samuel, Strecker, Angela L. Year: 2013 The New Zealand mud snail (Potamopyrgus antipodarum; NZMS) is an invasive species found in a variety of ecosystems in Oregon, including brackish estuaries, heavily used recreational rivers, and highly trafficked coastal freshwater lakes. NZMS are an invasive species of concern because once established, they may out-compete native invertebrate grazers, such as native insect larvae that provide important food resources for fish, and NZMS themselves provide little nutritional value. Monitoring for the presence and population density of NZMS was performed at boat ramps located along several water bodies in 2006 – 2007. These water bodies were then re-sampled during the summer of 2012 and winter of 2013 to investigate changes in population densities, as well as the potential spread of NZMS. In addition, six brackish estuaries and six freshwater coastal lakes were sampled in the summer of 2013 once again for population densities but also for stable isotope analysis to better understand the influence NZMS may have on these different ecosystem food webs. This work addresses how NZMS densities differ across invaded sites, how densities vary over time, how community diversity in rivers and estuaries varies between sites and over time, whether there is a correlation between NZMS densities and invertebrate diversity, and whether NZMS density correlates with decreasing dietary specificity for competing benthic invertebrates. Samples were sorted, identified, and counted, and stable isotope analyses from the summer 2013 field season were conducted on macroinvertebrates, zooplankton, and primary producers at the UC Davis Stable Isotope Facility. NZMS densities were found to be dynamic, with population densities increasing and decreasing over time and space. Additionally, two waterbodies (the lower Siuslaw River and the Nestucca River Estuary) previously without reported NZMS presence were identified to have established NZMS populations. Across invaded sites during the 2006 and 2012 sampling periods, there was a strong negative correlation between NZMS density and the diversity of the benthic invertebrate community. Within sites, no significant correlation was detected. High NZMS population densities were found to have a significantly negative relationship with detritivore density populations in the freshwater lake sites sampled in the summer of 2013. There were no significant relationships between NZMS and the density of any particular macroinvertebrate feeding habit group in estuaries. Additionally, stable isotope analyses indicated that NZMS at high population densities in the freshwater lakes share a similar stable isotope signature with macroinvertebrate herbivores, but NZMS had a more specific or narrow dietary range suggesting macroinvertebrate herbivores had more generalized diets than NZMS when at high densities. Conversely, NZMS population densities in the brackish estuary ecosystems showed no discernable patterns from the stable isotope analyses to indicate that their presence, either at high or low density, had an effect on the estuarine food webs. We concluded that continued research on long term population dynamics of invasive species like NZMS and their effects on native food webs remain crucial to future management and mitigation. Close

• 1423. [Article] Effects of residual trees on growth of young to mature Douglas-fir and western hemlock in the western central Oregon Cascades

  The purpose of this study was to assess how growth of young to mature Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sar.) in mixed stands was influenced ...

  Citation × Citation Citation Abstract Copy Title: Effects of residual trees on growth of young to mature Douglas-fir and western hemlock in the western central Oregon Cascades Author: Zenner, Eric K. The purpose of this study was to assess how growth of young to mature Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sar.) in mixed stands was influenced by the presence of residual trees. Fourteen paired plots with and without residual trees were examined in a retrospective study on the Willamette National Forest, Oregon. Growth was analyzed at the stand level, and at the individual tree level, contrasting growth behavior of Douglas-fir and western hemlock. Stands were generally highly stocked with relative densities between 0.38 and 1.05 and age ranged between 55 and 121 years. Results indicate that both understory and residual tree densities had a major influence on average tree size and growth and yield of the young cohort. At the stand level, residual trees and high understory densities reduced volume, basal area, and the mean squared diameter of the young cohort, while understory mortality increased. The influence of residual tree density on total understory and Douglas-fir volume and basal area was best fit by a negative logarithmic function. After accounting for understory density effects, the decrease of understory volume and basal area per individual residual tree decreased with increasing residual tree density. With 5 to 50 residual trees/ha, total understory volume reduction was 22 and 45%, respectively, averaging 2.4 and 1.5% per residual tree, respectively. In mixed stands, Douglas-fir volume and basal area declined more rapidly than the volume and basal area of the entire young cohort, when residual tree density exceeded 15 trees/ha. This was probably due to the relative shade-intolerance of Douglas-fir. Douglas-fir volume and basal area on southerly aspects was more than double the values on northerly aspects. Examination of quadratic mean diameters and radial growth rates by crown class revealed that the average size and growth rates of dominant Douglas-fir were not reduced by residual trees. However, the number and basal area of understory trees, particularly dominant and codominant Douglas-fir, declined with increasing residual tree densities. Understory volume was highest in stands that had lowest understory densities. High understory stocking levels were associated with reduced growth and high mortality rates of the young cohort, suggesting stands were undergoing self-thinning. At the individual tree level, basal area growth and diameter growth of trees increased with increasing size and dominance. The marginal effect of residual trees declined with increasing numbers of residual trees per hectare. No residual tree effects on heights of dominant Douglas-fir was found, perhaps because the few dominant Douglas-firs may have been located sufficiently far from residual trees to minimize interaction. Due to high stocking levels in the young cohort, results from this study only apply to stands with relative densities above 0.38. In addition, leave-trees in managed stands may be younger, smaller, and may have different growth rates from residual trees in this study, thus affecting the young cohort differently. Finally, due to the observational nature of this study, cause-and-effect relationships cannot be established. However, since understory volume was highest in stands with low understory densities, understory density management may reduce growth losses from self-thinning of the young cohort and competition from leave-trees. Title: Effects of residual trees on growth of young to mature Douglas-fir and western hemlock in the western central Oregon Cascades Author: Zenner, Eric K. The purpose of this study was to assess how growth of young to mature Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sar.) in mixed stands was influenced by the presence of residual trees. Fourteen paired plots with and without residual trees were examined in a retrospective study on the Willamette National Forest, Oregon. Growth was analyzed at the stand level, and at the individual tree level, contrasting growth behavior of Douglas-fir and western hemlock. Stands were generally highly stocked with relative densities between 0.38 and 1.05 and age ranged between 55 and 121 years. Results indicate that both understory and residual tree densities had a major influence on average tree size and growth and yield of the young cohort. At the stand level, residual trees and high understory densities reduced volume, basal area, and the mean squared diameter of the young cohort, while understory mortality increased. The influence of residual tree density on total understory and Douglas-fir volume and basal area was best fit by a negative logarithmic function. After accounting for understory density effects, the decrease of understory volume and basal area per individual residual tree decreased with increasing residual tree density. With 5 to 50 residual trees/ha, total understory volume reduction was 22 and 45%, respectively, averaging 2.4 and 1.5% per residual tree, respectively. In mixed stands, Douglas-fir volume and basal area declined more rapidly than the volume and basal area of the entire young cohort, when residual tree density exceeded 15 trees/ha. This was probably due to the relative shade-intolerance of Douglas-fir. Douglas-fir volume and basal area on southerly aspects was more than double the values on northerly aspects. Examination of quadratic mean diameters and radial growth rates by crown class revealed that the average size and growth rates of dominant Douglas-fir were not reduced by residual trees. However, the number and basal area of understory trees, particularly dominant and codominant Douglas-fir, declined with increasing residual tree densities. Understory volume was highest in stands that had lowest understory densities. High understory stocking levels were associated with reduced growth and high mortality rates of the young cohort, suggesting stands were undergoing self-thinning. At the individual tree level, basal area growth and diameter growth of trees increased with increasing size and dominance. The marginal effect of residual trees declined with increasing numbers of residual trees per hectare. No residual tree effects on heights of dominant Douglas-fir was found, perhaps because the few dominant Douglas-firs may have been located sufficiently far from residual trees to minimize interaction. Due to high stocking levels in the young cohort, results from this study only apply to stands with relative densities above 0.38. In addition, leave-trees in managed stands may be younger, smaller, and may have different growth rates from residual trees in this study, thus affecting the young cohort differently. Finally, due to the observational nature of this study, cause-and-effect relationships cannot be established. However, since understory volume was highest in stands with low understory densities, understory density management may reduce growth losses from self-thinning of the young cohort and competition from leave-trees. Close

• 1424. [Article] Investigation of solution-based processes for functional metal oxides : printing, nanostructures, and applications

  The various solution-based processes, spin coating, inkjet printing, microreactor assisted nanoparticle deposition (MANDTM) and spin-successive ionic layer absorption and reaction (Spin-SILAR) were used ...

  Citation × Citation Citation Abstract Copy Title: Investigation of solution-based processes for functional metal oxides : printing, nanostructures, and applications Author: Han, Seung-Yeol The various solution-based processes, spin coating, inkjet printing, microreactor assisted nanoparticle deposition (MANDTM) and spin-successive ionic layer absorption and reaction (Spin-SILAR) were used to demonstrate thin film electronics and anti-reflective coatings. Several aspects of thin film transistors (TFTs) were tested including a range of temperatures, annealing atmosphere, and deposition methods. At high processing temperature, TFTs with spin coated-InO, -IWO, -IZO and -IGO achieved high mobilites of 55.26, 37.86, 6.06 and 5.50 cm²/V•s, some of the highest reported mobilities for the spin coating process. Inkjet printed-ZTO, -IGZO and -IGTO from metal halide chemistry were fabricated and achieved mobilities of 3.09, 25.62 and 14.96 cm²/V•s, the highest reported values in inkjet printed TFTs. At low processing temperature, an ozone annealing process was adopted. TFTs with spin coated InO, IWO and IZO were processed with ozone. High mobilities of 0.85 ~ 16.76 cm²/V•s and I[subscript on/off] of 10⁵ ~ 10⁶ were achieved with the ozone annealing process at temperatures as low as 200 °C. A newly developed MANDTM system was used to fabricate ZnO TFTs which were shown to have strong potential for high performance devices made with low processing temperature. In addition, solution processing was used to produce anti-reflective coating of biomimic moth-eye structure on polished aluminum substrates, a textured silicon surface, glass slides and eyeglass lenses. Two films materials were explored - ZnO nanostructures, by MANDTM, and silica nanoparticles, by batch process - in which experimental conditions were tested and characterized. On aluminum two ZnO nanostructures were created by controlling temperature, flower-like shapes which dramatically reduced reflectance from ~65% to ~4% and chrysanthemum shapes which reduced reflectance down to ~0.7%. On silicon, pyramid shaped texture reduced reflectance and was used with and without a Ag nanoparticle seed layer as a substrate for ZnO nanostructures; the presence of a seed layer initiated a unique orzo nanostructured shape, which minimized anti-reflectance for silicon from 30.8% of polished silicon, 10.6% of textured silicon to 3.4% with the orzo structure. SiO₂ nanoparticles were deposited on glass and CR-39 substrates with and without hardcoat material and it was found that the smallest produced SiO₂ nanoparticles gave the highest performance and that a very dilute layer of hard coat material followed by nanoparticle deposition, and again followed by a very dilute layer of hard coat material was successful in preserving the biomimic nanostructure of the film and producing a minimized reflectance of as low as 1%, while maintaining a higher durability than commercially available products. Overall, these films achieved a minimization in reflectance and high durability. Title: Investigation of solution-based processes for functional metal oxides : printing, nanostructures, and applications Author: Han, Seung-Yeol The various solution-based processes, spin coating, inkjet printing, microreactor assisted nanoparticle deposition (MANDTM) and spin-successive ionic layer absorption and reaction (Spin-SILAR) were used to demonstrate thin film electronics and anti-reflective coatings. Several aspects of thin film transistors (TFTs) were tested including a range of temperatures, annealing atmosphere, and deposition methods. At high processing temperature, TFTs with spin coated-InO, -IWO, -IZO and -IGO achieved high mobilites of 55.26, 37.86, 6.06 and 5.50 cm²/V•s, some of the highest reported mobilities for the spin coating process. Inkjet printed-ZTO, -IGZO and -IGTO from metal halide chemistry were fabricated and achieved mobilities of 3.09, 25.62 and 14.96 cm²/V•s, the highest reported values in inkjet printed TFTs. At low processing temperature, an ozone annealing process was adopted. TFTs with spin coated InO, IWO and IZO were processed with ozone. High mobilities of 0.85 ~ 16.76 cm²/V•s and I[subscript on/off] of 10⁵ ~ 10⁶ were achieved with the ozone annealing process at temperatures as low as 200 °C. A newly developed MANDTM system was used to fabricate ZnO TFTs which were shown to have strong potential for high performance devices made with low processing temperature. In addition, solution processing was used to produce anti-reflective coating of biomimic moth-eye structure on polished aluminum substrates, a textured silicon surface, glass slides and eyeglass lenses. Two films materials were explored - ZnO nanostructures, by MANDTM, and silica nanoparticles, by batch process - in which experimental conditions were tested and characterized. On aluminum two ZnO nanostructures were created by controlling temperature, flower-like shapes which dramatically reduced reflectance from ~65% to ~4% and chrysanthemum shapes which reduced reflectance down to ~0.7%. On silicon, pyramid shaped texture reduced reflectance and was used with and without a Ag nanoparticle seed layer as a substrate for ZnO nanostructures; the presence of a seed layer initiated a unique orzo nanostructured shape, which minimized anti-reflectance for silicon from 30.8% of polished silicon, 10.6% of textured silicon to 3.4% with the orzo structure. SiO₂ nanoparticles were deposited on glass and CR-39 substrates with and without hardcoat material and it was found that the smallest produced SiO₂ nanoparticles gave the highest performance and that a very dilute layer of hard coat material followed by nanoparticle deposition, and again followed by a very dilute layer of hard coat material was successful in preserving the biomimic nanostructure of the film and producing a minimized reflectance of as low as 1%, while maintaining a higher durability than commercially available products. Overall, these films achieved a minimization in reflectance and high durability. Close

• 1425. [Article] Late quaternary oceanic circulation along the Pacific Coast of South America

  The distribution patterns of quartz and opal contents and the distribution patterns of radiolarian assemblages, in the sediments of the southeastern Pacific, are largely controlled by both the surface ...

  Citation × Citation Citation Abstract Copy Title: Late quaternary oceanic circulation along the Pacific Coast of South America Author: Molina-Cruz, Adolfo The distribution patterns of quartz and opal contents and the distribution patterns of radiolarian assemblages, in the sediments of the southeastern Pacific, are largely controlled by both the surface winds and the mixed-layer oceanic circulation. The distribution pattern of quartz is related to eolian and ice-rafted transport, as well as to runoff. In the subtropical region, quartz distribution extends offshore of Peru as a tongue in the same direction and position as the prevailing trade winds. Along the South American and Antarctic coast, high quartz concentrations are found in patches near shore or abundances commonly decrease rapidly seaward. Opal distribution follows the mixed-layer circulation around the subtropical anticyclonic gyre and shows high values under areas of oceanic divergence, characterized by high primary productivity. Along the continental margins, opal abundances are diluted by terrigenous debris; even off the Peruvian coast, where strong upwelling occurs and consequently high primary productivity prevails The distribution patterns of six radiolarian assemblages, defined through Q-mode factor analysis, reflect the geographical distribution of water masses associated with both surface and subsurface circulation. These are: 1) the surface Antarctic water mass, 2) the surface Subantarctic-Temperate water mass, 3) the Chile Current, 4) the Peru Current, 5) the surface Subtropical water mass and 6) the Equatorial Undercurrent. The Equatorial Undercurrent surfaces either because of strong trade winds or because of considerable relaxed trade winds. The above mentioned distribution patterns have shifted geographically during the Late Quaternary because of global climatic changes (glacial and interglacial stages). Fluctuations in the strength of the winds have been concurrent with fluctuations in the amount of ice stored on the continents, represented by the δ18O stratigraphic record, however, the direction and position of the winds have varied in a rather complex manner. Consequently, the oceanic circulation and associated water masses have presented a different behavior within each of the last five δ18O stages. Approximately 127,000 years ago, at the δ18O stage 5/6 boundary, the oceanographic conditions along the Pacific coast of South America were like the ones observed presently. During δ18O stage 5, weak trade winds, probably less parallel to the Peruvian coast than at the present, caused reduction in coastal upwelling and allowed advection of subantarctic-temperate waters, via the Chi1 Current, along the Peruvian coast. During δ18O stage 4, the trade winds were strong and more parallel to the equator, even to the east of the Galapagos Islands This gave rise to surfacing of the Equatorial Undercurrent through divergence processes Because of weak trade winds, the Galapagos front was positioned nearer to the South American coast during the lower part of stage 3. During the upper δ18O stage 3 and stage 2, the Pacific coast of South America experienced an intensified circulation, a strong development of upwelling, and as a result "cool" surface water temperatures. Approximately 18,000 years ago, at the climax of the last glaciation (δ18O stage 2), sea surface temperatures in the subtropical southeastern Pacific, were as much as 4°C cooler than present during the austral winter. It appears that the trend to the present oceanographic conditions began first in high latitudes and later in the tropical regions. Similar features in oceanographic changes were also observed during the onset of δ18O stage 5. A significant waning of the Antarctic ice occurred approximately 400,000 years ago. This was preceded by a considerable waxing of the Antarctic ice close to the Brunhes-Matuyama paleo-magnetic boundary (approximately 700,000 years ago). During the last 700,000 years the Polar front zone has shifted from its present position toward the north. Title: Late quaternary oceanic circulation along the Pacific Coast of South America Author: Molina-Cruz, Adolfo The distribution patterns of quartz and opal contents and the distribution patterns of radiolarian assemblages, in the sediments of the southeastern Pacific, are largely controlled by both the surface winds and the mixed-layer oceanic circulation. The distribution pattern of quartz is related to eolian and ice-rafted transport, as well as to runoff. In the subtropical region, quartz distribution extends offshore of Peru as a tongue in the same direction and position as the prevailing trade winds. Along the South American and Antarctic coast, high quartz concentrations are found in patches near shore or abundances commonly decrease rapidly seaward. Opal distribution follows the mixed-layer circulation around the subtropical anticyclonic gyre and shows high values under areas of oceanic divergence, characterized by high primary productivity. Along the continental margins, opal abundances are diluted by terrigenous debris; even off the Peruvian coast, where strong upwelling occurs and consequently high primary productivity prevails The distribution patterns of six radiolarian assemblages, defined through Q-mode factor analysis, reflect the geographical distribution of water masses associated with both surface and subsurface circulation. These are: 1) the surface Antarctic water mass, 2) the surface Subantarctic-Temperate water mass, 3) the Chile Current, 4) the Peru Current, 5) the surface Subtropical water mass and 6) the Equatorial Undercurrent. The Equatorial Undercurrent surfaces either because of strong trade winds or because of considerable relaxed trade winds. The above mentioned distribution patterns have shifted geographically during the Late Quaternary because of global climatic changes (glacial and interglacial stages). Fluctuations in the strength of the winds have been concurrent with fluctuations in the amount of ice stored on the continents, represented by the δ18O stratigraphic record, however, the direction and position of the winds have varied in a rather complex manner. Consequently, the oceanic circulation and associated water masses have presented a different behavior within each of the last five δ18O stages. Approximately 127,000 years ago, at the δ18O stage 5/6 boundary, the oceanographic conditions along the Pacific coast of South America were like the ones observed presently. During δ18O stage 5, weak trade winds, probably less parallel to the Peruvian coast than at the present, caused reduction in coastal upwelling and allowed advection of subantarctic-temperate waters, via the Chi1 Current, along the Peruvian coast. During δ18O stage 4, the trade winds were strong and more parallel to the equator, even to the east of the Galapagos Islands This gave rise to surfacing of the Equatorial Undercurrent through divergence processes Because of weak trade winds, the Galapagos front was positioned nearer to the South American coast during the lower part of stage 3. During the upper δ18O stage 3 and stage 2, the Pacific coast of South America experienced an intensified circulation, a strong development of upwelling, and as a result "cool" surface water temperatures. Approximately 18,000 years ago, at the climax of the last glaciation (δ18O stage 2), sea surface temperatures in the subtropical southeastern Pacific, were as much as 4°C cooler than present during the austral winter. It appears that the trend to the present oceanographic conditions began first in high latitudes and later in the tropical regions. Similar features in oceanographic changes were also observed during the onset of δ18O stage 5. A significant waning of the Antarctic ice occurred approximately 400,000 years ago. This was preceded by a considerable waxing of the Antarctic ice close to the Brunhes-Matuyama paleo-magnetic boundary (approximately 700,000 years ago). During the last 700,000 years the Polar front zone has shifted from its present position toward the north. Close

• 1426. [Article] An assessment of the change in the learning environment as perceived by junior high students whose teachers are participating in a field-centered teacher-education program

  Purpose of the Study Teacher education is changing to meet the needs of students going into teaching. Almost without exception, the emphasis is on some form of field study as a part of the professional ...

  Citation × Citation Citation Abstract Copy Title: An assessment of the change in the learning environment as perceived by junior high students whose teachers are participating in a field-centered teacher-education program Author: Coon, George Laus Purpose of the Study Teacher education is changing to meet the needs of students going into teaching. Almost without exception, the emphasis is on some form of field study as a part of the professional training. This study was an attempt to evaluate the effects of a field-centered teacher-education program on the boys and girls in classes to which trainees were assigned. In order to support or refute the basic premise of this study, nine hypotheses were formulated for testing. Procedures This research is restricted to 444 students in 20 classes of seventh, eighth, and ninth graders. They are included in 20 classes taught by ten teachers. The ten experimental classes, each under a different teacher, were matched against an equivalent number of control classes taught by the same teachers. Following a pre-test covering seven different areas of attitude, teacher trainees were assigned to the experimental classes. After eight weeks a post-test was administered and results of the two tests were compared. Also compared were the students' nine-week grades and Iowa Achievement Test scores. Included as support for the study were observations and comments of the principal, the teachers, the trainees, and the junior high students. Findings The findings of this study are presented in terms of their reference to the nine hypotheses: 1. The experimental group will have a significantly more positive attitude towards the teacher's mode of instruction. There was a significant difference, favoring the experimental group at the .05 level, and the hypothesis was accepted with confidence. 2. The experimental group will have a significantly more positive attitude toward the teacher's authority and control in the classroom. There was not a significant difference at the .05 level. The hypothesis, as stated, was refuted. 3. The experimental group will have a significantly more positive attitude toward the teacher's interpersonal relations. There was not a significant difference at the .05 level, and the hypothesis was refuted. 4. The experimental group will have a significantly, more positive sentiment toward the school social structure and climate. There was a significant difference favoring the experimental group beyond the .05 level, and the hypothesis was supported with confidence. 5. The experimental group will have a significantly more positive attitude toward learning. The results for this section of the test showed a significant difference beyond the .05 level of confidence favoring the experimental group. The hypothesis was supported with confidence. 6. The experimental group will have a significantly more positive sentiment toward school. There was a significant difference favoring the experimental group, and the hypothesis was supported with statistical purity. 7. The experimental group will have a significantly more positive sentiment toward their classmates. The experimental group was not significantly different. As stated, the hypothesis was refuted. 8. The experimental group will not differ significantly from the control group in terms of the teacher's grades. The grades received by the two groups were not significantly different at the .05 level. As stated, the hypothesis was supported.. 9. The experimental group will not differ significantly from the control group in terms of achievement as measured by the Iowa Test of Basic Skills. Again, there was not a significant difference, and the hypothesis was supported as stated. Conclusions It was concluded that teacher trainees assisting junior high teachers can create a more positive attitude toward the learning environment of students with whom they work. In all the data collected and all the observational evaluation made, there was none that indicated that the project was detrimental to the boys and girls. Recommendations 1. The results of this study demonstrate that teacher trainees can be of value in junior high school classes, and the schools should encourage their use. 2. Further study should be made to determine the most effective use of tutors by teachers. 3. Further studies should be made to determine ways of evaluating field-training experiences. Title: An assessment of the change in the learning environment as perceived by junior high students whose teachers are participating in a field-centered teacher-education program Author: Coon, George Laus Purpose of the Study Teacher education is changing to meet the needs of students going into teaching. Almost without exception, the emphasis is on some form of field study as a part of the professional training. This study was an attempt to evaluate the effects of a field-centered teacher-education program on the boys and girls in classes to which trainees were assigned. In order to support or refute the basic premise of this study, nine hypotheses were formulated for testing. Procedures This research is restricted to 444 students in 20 classes of seventh, eighth, and ninth graders. They are included in 20 classes taught by ten teachers. The ten experimental classes, each under a different teacher, were matched against an equivalent number of control classes taught by the same teachers. Following a pre-test covering seven different areas of attitude, teacher trainees were assigned to the experimental classes. After eight weeks a post-test was administered and results of the two tests were compared. Also compared were the students' nine-week grades and Iowa Achievement Test scores. Included as support for the study were observations and comments of the principal, the teachers, the trainees, and the junior high students. Findings The findings of this study are presented in terms of their reference to the nine hypotheses: 1. The experimental group will have a significantly more positive attitude towards the teacher's mode of instruction. There was a significant difference, favoring the experimental group at the .05 level, and the hypothesis was accepted with confidence. 2. The experimental group will have a significantly more positive attitude toward the teacher's authority and control in the classroom. There was not a significant difference at the .05 level. The hypothesis, as stated, was refuted. 3. The experimental group will have a significantly more positive attitude toward the teacher's interpersonal relations. There was not a significant difference at the .05 level, and the hypothesis was refuted. 4. The experimental group will have a significantly, more positive sentiment toward the school social structure and climate. There was a significant difference favoring the experimental group beyond the .05 level, and the hypothesis was supported with confidence. 5. The experimental group will have a significantly more positive attitude toward learning. The results for this section of the test showed a significant difference beyond the .05 level of confidence favoring the experimental group. The hypothesis was supported with confidence. 6. The experimental group will have a significantly more positive sentiment toward school. There was a significant difference favoring the experimental group, and the hypothesis was supported with statistical purity. 7. The experimental group will have a significantly more positive sentiment toward their classmates. The experimental group was not significantly different. As stated, the hypothesis was refuted. 8. The experimental group will not differ significantly from the control group in terms of the teacher's grades. The grades received by the two groups were not significantly different at the .05 level. As stated, the hypothesis was supported.. 9. The experimental group will not differ significantly from the control group in terms of achievement as measured by the Iowa Test of Basic Skills. Again, there was not a significant difference, and the hypothesis was supported as stated. Conclusions It was concluded that teacher trainees assisting junior high teachers can create a more positive attitude toward the learning environment of students with whom they work. In all the data collected and all the observational evaluation made, there was none that indicated that the project was detrimental to the boys and girls. Recommendations 1. The results of this study demonstrate that teacher trainees can be of value in junior high school classes, and the schools should encourage their use. 2. Further study should be made to determine the most effective use of tutors by teachers. 3. Further studies should be made to determine ways of evaluating field-training experiences. Close

• 1427. [Article] A comparison of the educational attitudes of eighth-grade students of Portland, Oregon : urban black and urban white

  This study was based on the assumption that urban black students hold more positive attitudes and opinions toward teachers, school, and education than urban white students. The black students were from ...

  Citation × Citation Citation Abstract Copy Title: A comparison of the educational attitudes of eighth-grade students of Portland, Oregon : urban black and urban white Author: Rini, Victor Matthew This study was based on the assumption that urban black students hold more positive attitudes and opinions toward teachers, school, and education than urban white students. The black students were from schools with a high concentration of lower-to-middle-class students and the white students were from schools with a high concentration of middle-to-upper-middle-class students. Both sets of students were from the metropolitan school district of Portland, Oregon. The purpose of this study was to compare differences in the educational attitudes and opinions of these two groups of students. In meeting this objective, it was first necessary to construct an appropriate survey-instrument composed of three separate scales of attitudes and opinions toward (a) teachers, (b) school, and (c) education. The instrument was comprised of thirty-three statements: eleven items having to do with teachers, eighteen items having to do with school, and four items having to do with education. Based on Portland Public Schools' academic and demographic data, eight schools were selected to participate in the study. Four schools had a high concentration of black students from lower-to-middle-class families and four schools had a high concentration of white students from middle-to-upper-middle-class families. A total of 213 eighth-grade students (100 black students and 113 white students) completed the attitude and opinion questionnaire during the week of April 21, 1975. Questionnaires were scored, allowing one point for each positive response, and no points for each negative or for no response. Appropriate statistical tests were used: three Student's "t" tests in testing differences of means between the two groups were applied to total, teacher, and school scores; and four Chi-Square tests in testing differences between the two groups were applied to four items having to do with the concept of education. In all tests, the .05 level of significance was used. The findings of the statistical tests revealed that these two racially- and socio-economically-different groups of students held essentially the same attitudes and opinions toward school and education. The tests, however, revealed that "the white group" was more positive toward teachers than "the black group," and that "the black group" was slightly more positive toward the concept of education than "the white group." Both sets of students responded equally toward statements concerning school. The assumption that "the black group" held more positive attitudes and opinions toward the composite of the concepts of teachers, school, and education was rejected. Because these two sets of students were from different racial and socio-economic backgrounds, the findings that they both valued school and education positively and almost equally is of importance. As pointed out by the literature, social class is not a determining factor in attitudes and opinions toward schooling. Based on this study, at least for these two groups of students, it was concluded that race does not influence attitudes toward school and education. Title: A comparison of the educational attitudes of eighth-grade students of Portland, Oregon : urban black and urban white Author: Rini, Victor Matthew This study was based on the assumption that urban black students hold more positive attitudes and opinions toward teachers, school, and education than urban white students. The black students were from schools with a high concentration of lower-to-middle-class students and the white students were from schools with a high concentration of middle-to-upper-middle-class students. Both sets of students were from the metropolitan school district of Portland, Oregon. The purpose of this study was to compare differences in the educational attitudes and opinions of these two groups of students. In meeting this objective, it was first necessary to construct an appropriate survey-instrument composed of three separate scales of attitudes and opinions toward (a) teachers, (b) school, and (c) education. The instrument was comprised of thirty-three statements: eleven items having to do with teachers, eighteen items having to do with school, and four items having to do with education. Based on Portland Public Schools' academic and demographic data, eight schools were selected to participate in the study. Four schools had a high concentration of black students from lower-to-middle-class families and four schools had a high concentration of white students from middle-to-upper-middle-class families. A total of 213 eighth-grade students (100 black students and 113 white students) completed the attitude and opinion questionnaire during the week of April 21, 1975. Questionnaires were scored, allowing one point for each positive response, and no points for each negative or for no response. Appropriate statistical tests were used: three Student's "t" tests in testing differences of means between the two groups were applied to total, teacher, and school scores; and four Chi-Square tests in testing differences between the two groups were applied to four items having to do with the concept of education. In all tests, the .05 level of significance was used. The findings of the statistical tests revealed that these two racially- and socio-economically-different groups of students held essentially the same attitudes and opinions toward school and education. The tests, however, revealed that "the white group" was more positive toward teachers than "the black group," and that "the black group" was slightly more positive toward the concept of education than "the white group." Both sets of students responded equally toward statements concerning school. The assumption that "the black group" held more positive attitudes and opinions toward the composite of the concepts of teachers, school, and education was rejected. Because these two sets of students were from different racial and socio-economic backgrounds, the findings that they both valued school and education positively and almost equally is of importance. As pointed out by the literature, social class is not a determining factor in attitudes and opinions toward schooling. Based on this study, at least for these two groups of students, it was concluded that race does not influence attitudes toward school and education. Close

• 1428. [Article] Metabolic Effects in C57B/6J Mice Fed a High-Fat Diet Supplemented With Walnuts, Raspberries and Other Whole Foods

  Health benefits obtained from consumption of fruits and vegetables have the potential to improve the lifestyle of individuals. The walnut is a polyunsaturated fatty acid (PUFA)-rich whole food that is ...

  Citation × Citation Citation Abstract Copy Title: Metabolic Effects in C57B/6J Mice Fed a High-Fat Diet Supplemented With Walnuts, Raspberries and Other Whole Foods Author: Miranda-Garcia, Omar Health benefits obtained from consumption of fruits and vegetables have the potential to improve the lifestyle of individuals. The walnut is a polyunsaturated fatty acid (PUFA)-rich whole food that is readily available in the U.S and has been shown to potentially reduce risk of Metabolic Syndrome. Furthermore, consumption of polyphenol rich plant-based foods have also been shown to be negatively correlated with the risk of the development of chronic diseases. In Study 1 we tested the hypothesis that addition of walnut and polyphenol-rich foods to a high-fat obesogenic diet (HF) would improve metabolism in male C57BL/6J mice. Mice were provided HF supplemented with walnut (W), or W diet supplemented with blueberry (W+BB), raspberry (W+RB), apple (W+AP), cranberry (W+CB), cherry (W+CH), broccoli (W+BR) and green tea (GT) for 9 weeks. Animals were fed experimental diets ad libitum; body weight, glucose tolerance, liver lipid accumulation, and expression of genes associated with lipid metabolism and inflammation were measured. Glucose tolerance was significantly lower in W+RB when compared to HF, meanwhile W+AP showed an intermediate value between W+RB and HF. A custom-designed focused gene array was used to evaluate expression of 87 different mRNAs. A subset of six groups were evaluated: LF, HF, W, W+RB, W+CH, and W+GT. Finally, a biochemical evaluation of 594 different metabolites was conducted and examined by principle component analysis (PCA). In Study 2 mice were fed experimental diets for ten weeks. Diets were formulated to include a typical dietary level of whole raspberry food products: HF+ raspberry juice concentrate (RJC), HF+ raspberry puree concentrate (RPC), HF+ raspberry fruit powder (RFP), and HF+ raspberry seed extract (RSE). Body weight, glucose tolerance, liver lipid accumulation, and expression of genes associated with lipid metabolism and inflammation were observed. Addition of raspberry food products to high-fat diet reduced body weight gain significantly, particularly for raspberry juice and puree concentrates. Serum insulin and resistin levels were measured and suggest intake of raspberry products and phytochemicals improve glucose control. A histological evaluation of liver tissue indicates a profound increase in liver lipid content in all high-fat fed mice. However, intake of raspberry puree concentrate appeared to reduce liver lipid levels compared to other groups fed high-fat diets. A custom-designed focused gene array was used to evaluate expression of 87 different mRNAs related to hepatic lipid and carbohydrate metabolism, inflammation, nuclear hormone reception action, and other cell signaling pathways We demonstrated that intake of walnut, alone, or in combination with a polyphenol-rich food, and consumption of raspberry and raspberry products, may have significant effects on physiological parameters related to metabolic syndrome and changes in hepatic gene expression levels consistent with an improved metabolic state. Title: Metabolic Effects in C57B/6J Mice Fed a High-Fat Diet Supplemented With Walnuts, Raspberries and Other Whole Foods Author: Miranda-Garcia, Omar Health benefits obtained from consumption of fruits and vegetables have the potential to improve the lifestyle of individuals. The walnut is a polyunsaturated fatty acid (PUFA)-rich whole food that is readily available in the U.S and has been shown to potentially reduce risk of Metabolic Syndrome. Furthermore, consumption of polyphenol rich plant-based foods have also been shown to be negatively correlated with the risk of the development of chronic diseases. In Study 1 we tested the hypothesis that addition of walnut and polyphenol-rich foods to a high-fat obesogenic diet (HF) would improve metabolism in male C57BL/6J mice. Mice were provided HF supplemented with walnut (W), or W diet supplemented with blueberry (W+BB), raspberry (W+RB), apple (W+AP), cranberry (W+CB), cherry (W+CH), broccoli (W+BR) and green tea (GT) for 9 weeks. Animals were fed experimental diets ad libitum; body weight, glucose tolerance, liver lipid accumulation, and expression of genes associated with lipid metabolism and inflammation were measured. Glucose tolerance was significantly lower in W+RB when compared to HF, meanwhile W+AP showed an intermediate value between W+RB and HF. A custom-designed focused gene array was used to evaluate expression of 87 different mRNAs. A subset of six groups were evaluated: LF, HF, W, W+RB, W+CH, and W+GT. Finally, a biochemical evaluation of 594 different metabolites was conducted and examined by principle component analysis (PCA). In Study 2 mice were fed experimental diets for ten weeks. Diets were formulated to include a typical dietary level of whole raspberry food products: HF+ raspberry juice concentrate (RJC), HF+ raspberry puree concentrate (RPC), HF+ raspberry fruit powder (RFP), and HF+ raspberry seed extract (RSE). Body weight, glucose tolerance, liver lipid accumulation, and expression of genes associated with lipid metabolism and inflammation were observed. Addition of raspberry food products to high-fat diet reduced body weight gain significantly, particularly for raspberry juice and puree concentrates. Serum insulin and resistin levels were measured and suggest intake of raspberry products and phytochemicals improve glucose control. A histological evaluation of liver tissue indicates a profound increase in liver lipid content in all high-fat fed mice. However, intake of raspberry puree concentrate appeared to reduce liver lipid levels compared to other groups fed high-fat diets. A custom-designed focused gene array was used to evaluate expression of 87 different mRNAs related to hepatic lipid and carbohydrate metabolism, inflammation, nuclear hormone reception action, and other cell signaling pathways We demonstrated that intake of walnut, alone, or in combination with a polyphenol-rich food, and consumption of raspberry and raspberry products, may have significant effects on physiological parameters related to metabolic syndrome and changes in hepatic gene expression levels consistent with an improved metabolic state. Close

• 1429. [Article] The effects of alfalfa hay fiber and vitamin B₁₂ levels in body fluids on milk fat production in high-producing dairy cows

  The research presented in this thesis was designed to evaluate the effects of feeding alfalfa hays from the Klamath Basin of Oregon in practical dairy rations on milk fat production in high-producing Holstein ...

  Citation × Citation Citation Abstract Copy Title: The effects of alfalfa hay fiber and vitamin B₁₂ levels in body fluids on milk fat production in high-producing dairy cows Author: Dudley, Eric George The research presented in this thesis was designed to evaluate the effects of feeding alfalfa hays from the Klamath Basin of Oregon in practical dairy rations on milk fat production in high-producing Holstein cows. Thirty-two second lactation or older animals estimated to be capable of producing at least 70 lbs of milk daily were utilized in a 4 X 4 latin square experiment with eight replications. Four rations based upon four different lots of hay, ranging from 15.2 to 22.0% crude protein (CP), from 29.9 to 35.1% acid detergent fiber (ADF) and from 109 to 132 in Relative Feed Value, were fed during four periods, each lasting about 28 days. Rations were formulated to be comparable in caloric and nitrogen content, and all consisted (as a percent of ration dry matter) of 50% concentrate, 30% chopped alfalfa and 20% corn silage, fed as a mixed, complete ration. A digestibility study was also carried out involving four steers fed the four alfalfa hays only. The digestibility trial showed that there were no significant differences among the four alfalfa hays in feed intake, % digestible dry matter, % digestible ADF and % digestible CP. In the production trial, no differences were seen in feed intake or persistency, and body weight changes were significantly different only for periods. Both daily 4% fat-corrected milk (FCM) and milk fat percentage were observed to have highly significant differences for all sources of variation except treatments. Treatment means for rations 1 through 4 for 4% FCM were 48.88, 48.02, 48.38 and 48.24 lbs, respectively, and those for percent milk fat were 3.13, 3.12, 3.05 and 3.01, respectively. Differences in other sources of variation for these two measurements were attributed to variation among cows and stage of lactation effects. Important changes were noted in the relative proportions of volatile fatty acids in the rumen. While there were no significant changes in rumen acetate concentration, highly significant differences in propionate content were seen for all sources of variation. Treatment means for rations 1 to 4 were 18.14, 17.56, 19.44 and 23.03 pmoles /ml of rumen fluid. This response was reflected also in highly significant differences in ruminal acetate:propionate (A:P) ratios. Means here for rations 1 through It were 2.82, 3.00, 2.36 and 2.23, respectively. Correlation coefficients were determined for A:P ratios and several hay and ration characteristics, and only that with hay % NDF was significant. It was concluded that changes in rumen fermentation typical of milk fat depression occurred which were not severe enough to actually reduce butterfat levels. The literature indicates that there may be a relationship between milk fat synthesis and tissue vitamin B₁₂ status, i.e., that B₁₂- deficient animals will secrete milk with reduced fat percentage. In this experiment, serum vitamin B₁₂ levels did not respond significantly to treatments, nor did fat percentage, the correlation between them was very low, and there was no indication of vitamin B₁₂ deficiency among experimental animals. Our results, therefore, are interpreted as not being in conflict with the hypothesized relationship. Title: The effects of alfalfa hay fiber and vitamin B₁₂ levels in body fluids on milk fat production in high-producing dairy cows Author: Dudley, Eric George The research presented in this thesis was designed to evaluate the effects of feeding alfalfa hays from the Klamath Basin of Oregon in practical dairy rations on milk fat production in high-producing Holstein cows. Thirty-two second lactation or older animals estimated to be capable of producing at least 70 lbs of milk daily were utilized in a 4 X 4 latin square experiment with eight replications. Four rations based upon four different lots of hay, ranging from 15.2 to 22.0% crude protein (CP), from 29.9 to 35.1% acid detergent fiber (ADF) and from 109 to 132 in Relative Feed Value, were fed during four periods, each lasting about 28 days. Rations were formulated to be comparable in caloric and nitrogen content, and all consisted (as a percent of ration dry matter) of 50% concentrate, 30% chopped alfalfa and 20% corn silage, fed as a mixed, complete ration. A digestibility study was also carried out involving four steers fed the four alfalfa hays only. The digestibility trial showed that there were no significant differences among the four alfalfa hays in feed intake, % digestible dry matter, % digestible ADF and % digestible CP. In the production trial, no differences were seen in feed intake or persistency, and body weight changes were significantly different only for periods. Both daily 4% fat-corrected milk (FCM) and milk fat percentage were observed to have highly significant differences for all sources of variation except treatments. Treatment means for rations 1 through 4 for 4% FCM were 48.88, 48.02, 48.38 and 48.24 lbs, respectively, and those for percent milk fat were 3.13, 3.12, 3.05 and 3.01, respectively. Differences in other sources of variation for these two measurements were attributed to variation among cows and stage of lactation effects. Important changes were noted in the relative proportions of volatile fatty acids in the rumen. While there were no significant changes in rumen acetate concentration, highly significant differences in propionate content were seen for all sources of variation. Treatment means for rations 1 to 4 were 18.14, 17.56, 19.44 and 23.03 pmoles /ml of rumen fluid. This response was reflected also in highly significant differences in ruminal acetate:propionate (A:P) ratios. Means here for rations 1 through It were 2.82, 3.00, 2.36 and 2.23, respectively. Correlation coefficients were determined for A:P ratios and several hay and ration characteristics, and only that with hay % NDF was significant. It was concluded that changes in rumen fermentation typical of milk fat depression occurred which were not severe enough to actually reduce butterfat levels. The literature indicates that there may be a relationship between milk fat synthesis and tissue vitamin B₁₂ status, i.e., that B₁₂- deficient animals will secrete milk with reduced fat percentage. In this experiment, serum vitamin B₁₂ levels did not respond significantly to treatments, nor did fat percentage, the correlation between them was very low, and there was no indication of vitamin B₁₂ deficiency among experimental animals. Our results, therefore, are interpreted as not being in conflict with the hypothesized relationship. Close

• 1430. [Article] Physical activity, hormone replacement therapy, and insulin resistant coronary artery disease risk factors in postmenopausal women

  Low physical activity levels and high serum C-reactive protein (CRP) levels are risk factors for coronary artery disease (CAD) in both men and women. However, postmenopausal women who take hormone replacement ...

  Citation × Citation Citation Abstract Copy Title: Physical activity, hormone replacement therapy, and insulin resistant coronary artery disease risk factors in postmenopausal women Author: Manns, Patricia J. Low physical activity levels and high serum C-reactive protein (CRP) levels are risk factors for coronary artery disease (CAD) in both men and women. However, postmenopausal women who take hormone replacement therapy (HRT) may have increased risk of CAD because of HRT-related increases in serum CRP. There are two manuscripts in this dissertation. The purpose of the first manuscript was to determine whether higher physical activity energy expenditure was associated with lower serum CRP, independent of oral HRT status and body fatness, in 133 postmenopausal women. Higher physical activity energy expenditures were significantly associated with lower serum CRP levels (r=-0.21, p=0.0l9), independent of oral HRT use, age, smoking behavior, alcohol consumption, aspirin use, and statin use. However, in the complete multivariate model, which included body fat, the association between higher physical activity and lower serum CRP levels was abolished. The purpose of the second study was to quantify the biological variability of insulin resistant CAD risk factors in a sample of 8 postmenopausal women. Risk factor outcomes, including serum total cholesterol, serum triglycerides (TG), serum high-density lipoprotein cholesterol (HDL-C), serum glucose, plasma insulin, serum CRP, waist and hip circumferences, abdominal sagittal diameter, body fat, systolic (SBP) and diastolic blood pressure, and self-reported physical activity energy expenditure, were measured on two occasions, 7-12 days apart. High absolute biological variability values (by standard error of measurement) were observed for serum TG (32.0 mg/dl), serum CRP (5.6 mg/l), SBP (4.0 mmHg), and physical activity (9.4 kcal/kg/week). High relative biological variability (by within-subjects coefficient of variation ≥27.3%) was also observed for serum TG, serum CRP, and physical activity. Bland-Altman plots identified individual outliers for serum TG, serum CRP, plasma insulin, and SBP. Together, the results suggest that the correlations between lower levels of serum CRP and higher levels of physical activity, though significant, may have been attenuated by the high biological variability of both serum CRP and physical activity. Thus, the importance of higher levels of physical activity, in decreasing serum CRP and the concomitant risk of heart disease, may be underestimated in the absence of serial measurement of serum CRP and physical activity. Title: Physical activity, hormone replacement therapy, and insulin resistant coronary artery disease risk factors in postmenopausal women Author: Manns, Patricia J. Low physical activity levels and high serum C-reactive protein (CRP) levels are risk factors for coronary artery disease (CAD) in both men and women. However, postmenopausal women who take hormone replacement therapy (HRT) may have increased risk of CAD because of HRT-related increases in serum CRP. There are two manuscripts in this dissertation. The purpose of the first manuscript was to determine whether higher physical activity energy expenditure was associated with lower serum CRP, independent of oral HRT status and body fatness, in 133 postmenopausal women. Higher physical activity energy expenditures were significantly associated with lower serum CRP levels (r=-0.21, p=0.0l9), independent of oral HRT use, age, smoking behavior, alcohol consumption, aspirin use, and statin use. However, in the complete multivariate model, which included body fat, the association between higher physical activity and lower serum CRP levels was abolished. The purpose of the second study was to quantify the biological variability of insulin resistant CAD risk factors in a sample of 8 postmenopausal women. Risk factor outcomes, including serum total cholesterol, serum triglycerides (TG), serum high-density lipoprotein cholesterol (HDL-C), serum glucose, plasma insulin, serum CRP, waist and hip circumferences, abdominal sagittal diameter, body fat, systolic (SBP) and diastolic blood pressure, and self-reported physical activity energy expenditure, were measured on two occasions, 7-12 days apart. High absolute biological variability values (by standard error of measurement) were observed for serum TG (32.0 mg/dl), serum CRP (5.6 mg/l), SBP (4.0 mmHg), and physical activity (9.4 kcal/kg/week). High relative biological variability (by within-subjects coefficient of variation ≥27.3%) was also observed for serum TG, serum CRP, and physical activity. Bland-Altman plots identified individual outliers for serum TG, serum CRP, plasma insulin, and SBP. Together, the results suggest that the correlations between lower levels of serum CRP and higher levels of physical activity, though significant, may have been attenuated by the high biological variability of both serum CRP and physical activity. Thus, the importance of higher levels of physical activity, in decreasing serum CRP and the concomitant risk of heart disease, may be underestimated in the absence of serial measurement of serum CRP and physical activity. Close