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• 1. [Article] Twentieth-Century Trends in Runoff, Evapotranspiration, and Soil Moisture in the Western United States

  A physically based hydrology model is used to produce time series for the period 1916–2003 of evapotranspiration (ET), runoff, and soil moisture (SM) over the western United States from which long-term ...

  Citation × Citation Citation Abstract Copy Title: Twentieth-Century Trends in Runoff, Evapotranspiration, and Soil Moisture in the Western United States Author: Clark, Martyn P., Lettenmaier, Dennis P., Mote, Philip W., Hamlet, Alan F. A physically based hydrology model is used to produce time series for the period 1916–2003 of evapotranspiration (ET), runoff, and soil moisture (SM) over the western United States from which long-term trends are evaluated. The results show that trends in ET in spring and summer are determined primarily by trends in precipitation and snowmelt that determine water availability. From April to June, ET trends are mostly positive due primarily to earlier snowmelt and earlier emergence of snow-free ground, and secondarily to increasing trends in spring precipitation. From July to September trends in ET are more strongly influenced by precipitation trends, with the exception of areas (most notably California) that receive little summer precipitation and have experienced large changes in snowmelt timing. Trends in the seasonal timing of ET are modest, but during the period 1947–2003 when temperature trends are large, they reflect a shift of ET from midsummer to early summer and late spring. As in other studies, it is found that runoff is occurring earlier in spring, a trend that is related primarily to increasing temperature, and is most apparent during 1947–2003. Trends in the annual runoff ratio, a variable critical to western water management, are determined primarily by trends in cool season precipitation, rather than changes in the timing of runoff or ET. It was found that the signature of temperature-related trends in runoff and SM is strongly keyed to mean midwinter [December–February (DJF)] temperatures. Areas with warmer winter temperatures show increasing trends in the runoff fraction as early as February, and colder areas as late as June. Trends toward earlier spring SM recharge are apparent and increasing trends in SM on 1 April are evident over much of the region. The 1 July SM trends are less affected by snowmelt changes and are controlled more by precipitation trends. Title: Twentieth-Century Trends in Runoff, Evapotranspiration, and Soil Moisture in the Western United States Author: Clark, Martyn P., Lettenmaier, Dennis P., Mote, Philip W., Hamlet, Alan F. A physically based hydrology model is used to produce time series for the period 1916–2003 of evapotranspiration (ET), runoff, and soil moisture (SM) over the western United States from which long-term trends are evaluated. The results show that trends in ET in spring and summer are determined primarily by trends in precipitation and snowmelt that determine water availability. From April to June, ET trends are mostly positive due primarily to earlier snowmelt and earlier emergence of snow-free ground, and secondarily to increasing trends in spring precipitation. From July to September trends in ET are more strongly influenced by precipitation trends, with the exception of areas (most notably California) that receive little summer precipitation and have experienced large changes in snowmelt timing. Trends in the seasonal timing of ET are modest, but during the period 1947–2003 when temperature trends are large, they reflect a shift of ET from midsummer to early summer and late spring. As in other studies, it is found that runoff is occurring earlier in spring, a trend that is related primarily to increasing temperature, and is most apparent during 1947–2003. Trends in the annual runoff ratio, a variable critical to western water management, are determined primarily by trends in cool season precipitation, rather than changes in the timing of runoff or ET. It was found that the signature of temperature-related trends in runoff and SM is strongly keyed to mean midwinter [December–February (DJF)] temperatures. Areas with warmer winter temperatures show increasing trends in the runoff fraction as early as February, and colder areas as late as June. Trends toward earlier spring SM recharge are apparent and increasing trends in SM on 1 April are evident over much of the region. The 1 July SM trends are less affected by snowmelt changes and are controlled more by precipitation trends. Close

• 2. [Article] Google Trends: Is there any significant correlation between Google Search Volume Index and Actual World Trends?

  Google Trends is a powerful tool in extracting and comparing searched terms through the time. It simply shows the increasing or decreasing of searching times for any term on the biggest search engine on ...

  Citation × Citation Citation Abstract Copy Title: Google Trends: Is there any significant correlation between Google Search Volume Index and Actual World Trends? Author: Alizadeh, Yasser, Lingga, Marwan Mossa Year: 2010 Google Trends is a powerful tool in extracting and comparing searched terms through the time. It simply shows the increasing or decreasing of searching times for any term on the biggest search engine on the web. The goal of this paper is to find out whether Google Trends data has a significant correlation with the characteristics of the subject in the real world or not? For instance, is there any meaningful correlation between “volume search index” in Google Trends for a term like “Oil Price” and actual worldwide Oil price? This paper tests the hypothesis on two similar cases; “Oil Price” and “Gold Price” to answer the above question. Research findings have shown a strong correlation between Google Trends volume search index and actual real world data for both terms. We have concluded that Google Trends could be a valuable, fast and free tool to predict the trends of such a trends, although it definitely needs more studies for verification or generalize the method. Limitations of Google Trends and our research have been mentioned as well. Title: Google Trends: Is there any significant correlation between Google Search Volume Index and Actual World Trends? Author: Alizadeh, Yasser, Lingga, Marwan Mossa Year: 2010 Google Trends is a powerful tool in extracting and comparing searched terms through the time. It simply shows the increasing or decreasing of searching times for any term on the biggest search engine on the web. The goal of this paper is to find out whether Google Trends data has a significant correlation with the characteristics of the subject in the real world or not? For instance, is there any meaningful correlation between “volume search index” in Google Trends for a term like “Oil Price” and actual worldwide Oil price? This paper tests the hypothesis on two similar cases; “Oil Price” and “Gold Price” to answer the above question. Research findings have shown a strong correlation between Google Trends volume search index and actual real world data for both terms. We have concluded that Google Trends could be a valuable, fast and free tool to predict the trends of such a trends, although it definitely needs more studies for verification or generalize the method. Limitations of Google Trends and our research have been mentioned as well. Close

• 3. [Article] Structure and evolution of the Horse Heaven Hills in south-central Washington

  The Horse Heaven Hills uplift in south-central Washington consists of distinct northwest and northeast trends which merge in the lower Yakima Valley. The northwest trend is adjacent to and parallels the ...

  Citation × Citation Citation Abstract Copy Title: Structure and evolution of the Horse Heaven Hills in south-central Washington Author: Hagood, Michael Curtis Year: 1985 The Horse Heaven Hills uplift in south-central Washington consists of distinct northwest and northeast trends which merge in the lower Yakima Valley. The northwest trend is adjacent to and parallels the Rattlesnake-Wallula alignment (RAW; a part of the Olympic-Wallowa lineament). The northwest trend and northeast trend consist of aligned or en echelon anticlines and monoclines whose axes are generally oriented in the direction of the trend. At the intersection, folds in the northeast trend plunge onto and are terminated by folds of the northwest trend. Title: Structure and evolution of the Horse Heaven Hills in south-central Washington Author: Hagood, Michael Curtis Year: 1985 The Horse Heaven Hills uplift in south-central Washington consists of distinct northwest and northeast trends which merge in the lower Yakima Valley. The northwest trend is adjacent to and parallels the Rattlesnake-Wallula alignment (RAW; a part of the Olympic-Wallowa lineament). The northwest trend and northeast trend consist of aligned or en echelon anticlines and monoclines whose axes are generally oriented in the direction of the trend. At the intersection, folds in the northeast trend plunge onto and are terminated by folds of the northwest trend. Close

• 4. [Article] Precipitation Intensity Trend Detection using Hourly and Daily Observations in Portland, Oregon

  The intensity of precipitation is expected to increase in response to climate change, but the regions where this may occur are unclear. The lack of certainty from climate models warrants an examination ...

  Citation × Citation Citation Abstract Copy Title: Precipitation Intensity Trend Detection using Hourly and Daily Observations in Portland, Oregon Author: Cooley, Alexis, Chang, Heejun Year: 2017 The intensity of precipitation is expected to increase in response to climate change, but the regions where this may occur are unclear. The lack of certainty from climate models warrants an examination of trends in observational records. However, the temporal resolution of records may affect the success of trend detection. Daily observations are often used, but may be too coarse to detect changes. Sub-daily records may improve detection, but their value is not yet quantified. Using daily and hourly records from 24 rain gages in Portland, Oregon (OR), trends in precipitation intensity and volume are examined for the period of 1999–2015. Daily intensity is measured using the Simple Daily Intensity Index, and this method is adapted to measure hourly scale intensity. Kendall’s tau, a non-parametric correlation coefficient, is used for monotonic trend detection. Field significance and tests for spatial autocorrelation using Moran’s Index are used to determine the significance of group hypothesis tests. Results indicate that the hourly data is superior in trend detection when compared with daily data; more trends are detected with hourly scale data at both the 5% and 10% significance levels. Hourly records showed a significant increase in 6 of 12 months, while daily records showed a significant increase in 4 of 12 months at the 10% significance level. At both scales increasing trends were concentrated in spring and summer months, while no winter trends were detected. Volume was shown to be increasing in most months experiencing increased intensity, and is a probable driver of the intensity trends observed. Title: Precipitation Intensity Trend Detection using Hourly and Daily Observations in Portland, Oregon Author: Cooley, Alexis, Chang, Heejun Year: 2017 The intensity of precipitation is expected to increase in response to climate change, but the regions where this may occur are unclear. The lack of certainty from climate models warrants an examination of trends in observational records. However, the temporal resolution of records may affect the success of trend detection. Daily observations are often used, but may be too coarse to detect changes. Sub-daily records may improve detection, but their value is not yet quantified. Using daily and hourly records from 24 rain gages in Portland, Oregon (OR), trends in precipitation intensity and volume are examined for the period of 1999–2015. Daily intensity is measured using the Simple Daily Intensity Index, and this method is adapted to measure hourly scale intensity. Kendall’s tau, a non-parametric correlation coefficient, is used for monotonic trend detection. Field significance and tests for spatial autocorrelation using Moran’s Index are used to determine the significance of group hypothesis tests. Results indicate that the hourly data is superior in trend detection when compared with daily data; more trends are detected with hourly scale data at both the 5% and 10% significance levels. Hourly records showed a significant increase in 6 of 12 months, while daily records showed a significant increase in 4 of 12 months at the 10% significance level. At both scales increasing trends were concentrated in spring and summer months, while no winter trends were detected. Volume was shown to be increasing in most months experiencing increased intensity, and is a probable driver of the intensity trends observed. Close

• 5. [Article] Can Significant Trends be Detected in Surface Air Temperature and Precipitation Over South America in Recent Decades?

  Trends in near-surface air temperature and precipitation over South America are examined for the periods 1975–2004 and 1955–2004, respectively, using multiple observational and climate model data sets. ...

  Citation × Citation Citation Abstract Copy Title: Can Significant Trends be Detected in Surface Air Temperature and Precipitation Over South America in Recent Decades? Author: de Barros Soares, Daniel, Lee, Huikyo, Loikith, Paul C., Barkhordarian, Armineh, Mechoso, Carlos R. Year: 2016 Trends in near-surface air temperature and precipitation over South America are examined for the periods 1975–2004 and 1955–2004, respectively, using multiple observational and climate model data sets. The results for observed near-surface air temperature show an overall warming trend over much of the continent, with the largest magnitudes over central Brazil. These observed trends are found to be statistically significant using pre-industrial control simulations from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) as the baseline to estimate natural climate variability. The observed trends are compared with those obtained in natural-only CMIP5 simulations, in which only natural forcings (i.e. volcanoes and solar variability) are included, and in historical CMIP5 simulations, in which anthropogenic forcings (i.e. changes in the atmospheric composition) are further incorporated. The historical CMIP5 simulations are more successful in capturing the observed temperature trends than the simulations with natural forcings only. It is suggested that anthropogenic warming is already evident over much of South America. Unlike the warming trends, observed precipitation trends over South America are less spatially coherent with both negative and positive values across the continent. Significant positive trends are found over South America in only one of the data sets used, and over a region that roughly encompasses the southern part of La Plata Basin (southern Brazil, Uruguay, and northeastern Argentina) in all data sets used. The historical CMIP5 simulations do not capture this feature. No firm conclusions are reached, therefore, for anthropogenic influences on precipitation changes in the period selected for study. Title: Can Significant Trends be Detected in Surface Air Temperature and Precipitation Over South America in Recent Decades? Author: de Barros Soares, Daniel, Lee, Huikyo, Loikith, Paul C., Barkhordarian, Armineh, Mechoso, Carlos R. Year: 2016 Trends in near-surface air temperature and precipitation over South America are examined for the periods 1975–2004 and 1955–2004, respectively, using multiple observational and climate model data sets. The results for observed near-surface air temperature show an overall warming trend over much of the continent, with the largest magnitudes over central Brazil. These observed trends are found to be statistically significant using pre-industrial control simulations from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) as the baseline to estimate natural climate variability. The observed trends are compared with those obtained in natural-only CMIP5 simulations, in which only natural forcings (i.e. volcanoes and solar variability) are included, and in historical CMIP5 simulations, in which anthropogenic forcings (i.e. changes in the atmospheric composition) are further incorporated. The historical CMIP5 simulations are more successful in capturing the observed temperature trends than the simulations with natural forcings only. It is suggested that anthropogenic warming is already evident over much of South America. Unlike the warming trends, observed precipitation trends over South America are less spatially coherent with both negative and positive values across the continent. Significant positive trends are found over South America in only one of the data sets used, and over a region that roughly encompasses the southern part of La Plata Basin (southern Brazil, Uruguay, and northeastern Argentina) in all data sets used. The historical CMIP5 simulations do not capture this feature. No firm conclusions are reached, therefore, for anthropogenic influences on precipitation changes in the period selected for study. Close

• 6. [Article] Detecting Change in Rainstorm Properties from 1977-2016 and Associated Future Flood Risks in Portland, Oregon

  In response to increased greenhouse gases and global temperatures, changes to the hydrologic cycle are projected to occur and new precipitation characteristics are expected to emerge. The study of these ...

  Citation × Citation Citation Abstract Copy Title: Detecting Change in Rainstorm Properties from 1977-2016 and Associated Future Flood Risks in Portland, Oregon Author: Cooley, Alexis Kirsten Year: 2017 In response to increased greenhouse gases and global temperatures, changes to the hydrologic cycle are projected to occur and new precipitation characteristics are expected to emerge. The study of these characteristics is facilitated by common indices to measure precipitation and temperature developed by the Expert Team on Climate Change Detection and Indices (ETCCDI). These indices can be used to describe the likely consequences of climate change such as increased daily precipitation intensity (SDII) and heavier rainfall events (R95p). This study calculates a subset of these indices from observed and modelled precipitation data in Portland, Oregon. Five rainfall gages from a high resolution rain gage network and projections from three downscaled global climate models including CanESM2, CESM1, CNRM-CM5 are used to calculate precipitation indices. Mann-Kendall's tau is used to detect monotonic trends in indices. The observational record is compared with models for the historic period (1977-2005) and these past trends are compared with projected future trends (2006-2100). The influence of study unit on trend detection is analyzed by computing trends at the annual and monthly scale. Study unit is show to be important for trend detection. When the annual study unit is used, projected future trends towards increased precipitation intensity and event volumes are not observed in the historic data. However, when analyzed with a monthly study unit, trends towards increased precipitation intensity and event volumes are observed in the historic data. These trends are shown to be important for Portland area flooding, as precipitation indices are shown to significantly correlate with 40 maximum peak flow events that occurred during the period of study. Title: Detecting Change in Rainstorm Properties from 1977-2016 and Associated Future Flood Risks in Portland, Oregon Author: Cooley, Alexis Kirsten Year: 2017 In response to increased greenhouse gases and global temperatures, changes to the hydrologic cycle are projected to occur and new precipitation characteristics are expected to emerge. The study of these characteristics is facilitated by common indices to measure precipitation and temperature developed by the Expert Team on Climate Change Detection and Indices (ETCCDI). These indices can be used to describe the likely consequences of climate change such as increased daily precipitation intensity (SDII) and heavier rainfall events (R95p). This study calculates a subset of these indices from observed and modelled precipitation data in Portland, Oregon. Five rainfall gages from a high resolution rain gage network and projections from three downscaled global climate models including CanESM2, CESM1, CNRM-CM5 are used to calculate precipitation indices. Mann-Kendall's tau is used to detect monotonic trends in indices. The observational record is compared with models for the historic period (1977-2005) and these past trends are compared with projected future trends (2006-2100). The influence of study unit on trend detection is analyzed by computing trends at the annual and monthly scale. Study unit is show to be important for trend detection. When the annual study unit is used, projected future trends towards increased precipitation intensity and event volumes are not observed in the historic data. However, when analyzed with a monthly study unit, trends towards increased precipitation intensity and event volumes are observed in the historic data. These trends are shown to be important for Portland area flooding, as precipitation indices are shown to significantly correlate with 40 maximum peak flow events that occurred during the period of study. Close

• 7. [Article] Avian population trends within the evolving agricultural landscape of the eastern and central United States

  State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have ...

  Citation × Citation Citation Abstract Copy Title: Avian population trends within the evolving agricultural landscape of the eastern and central United States Author: Murphy, Michael T. Year: 2003 State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have driven population trends of grassland and shrub habitat birds over the past two decades. The degree to which population trends differed between grassland and shrub habitats was evaluated with respect to migratory and nesting behavior. Grassland birds declined significantly between 1980 and 1999, but, on average, shrub habitat species did not. Grassland-breeding, long-distance migrants exhibited the strongest negative trends. Most species (78%; n = 63) exhibited at least one significant association between population trends and changes in agricultural land use, and in most, land use "explained" 25-30% of the variation in population trends among states. Changes in the farmland landscape accounted for more of the interstate variability of population trends of short-distance migrants than of both long-distance migrants and residents, and that variability was greater in grassland than shrub species. Declines in the area of rangeland and cover crops were followed by population declines and increases, respectively, by many species. Increases of land in the Conservation Reserve Program had negative associations with population trends of some shrub species. The results indicate that grassland birds have declined strongly over the past two decades, and that regardless of migratory behavior or nesting habits, avian population trends are linked strongly to changes in agricultural land use within North America. Title: Avian population trends within the evolving agricultural landscape of the eastern and central United States Author: Murphy, Michael T. Year: 2003 State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have driven population trends of grassland and shrub habitat birds over the past two decades. The degree to which population trends differed between grassland and shrub habitats was evaluated with respect to migratory and nesting behavior. Grassland birds declined significantly between 1980 and 1999, but, on average, shrub habitat species did not. Grassland-breeding, long-distance migrants exhibited the strongest negative trends. Most species (78%; n = 63) exhibited at least one significant association between population trends and changes in agricultural land use, and in most, land use "explained" 25-30% of the variation in population trends among states. Changes in the farmland landscape accounted for more of the interstate variability of population trends of short-distance migrants than of both long-distance migrants and residents, and that variability was greater in grassland than shrub species. Declines in the area of rangeland and cover crops were followed by population declines and increases, respectively, by many species. Increases of land in the Conservation Reserve Program had negative associations with population trends of some shrub species. The results indicate that grassland birds have declined strongly over the past two decades, and that regardless of migratory behavior or nesting habits, avian population trends are linked strongly to changes in agricultural land use within North America. Close

• 8. [Article] Teachers' beliefs and willingness to be involved with certain aspects of Oregon home economics education curriculum

  The purpose of this study was designed to answer 1. What are the beliefs and attitudes that Oregon home economics teachers hold about various new trends? 2. Are Oregon home economics teachers willing to ...

  Citation × Citation Citation Abstract Copy Title: Teachers' beliefs and willingness to be involved with certain aspects of Oregon home economics education curriculum Author: Alexander, Capi Forsgren The purpose of this study was designed to answer 1. What are the beliefs and attitudes that Oregon home economics teachers hold about various new trends? 2. Are Oregon home economics teachers willing to support the various new trends? 3. Are Oregon home economics teachers willing to further prepare themselves to work with the trends? 4. Are Oregon home economics teachers willing to accept teaching responsibilities for the trends? 5. Are Oregon home economics teachers willing to assume leadership responsibilities for the trends? The six trends included in the study were related to programs for 1. The handicapped 2. The socio-economically disadvantaged 3. Occupational education 4. Coeducational classes 5. Specialized semester courses 6. Family life courses A questionnaire was constructed, validated, and sent to 394 home economics teachers in the State of Oregon to gain answers to the five questions as they related to the six trends. Of the questionnaires mailed out, 241 were returned and 160 (41 percent) were usable. Nearly one half of the respondents were 40 years of age or older. Approximately two thirds were married. Nearly 70 percent received their bachelor's degrees since 1940. Fewer than 15 percent of the respondents had master's degrees and over 80 percent of these were received since 1960. About one half of the teachers had taken from 1-42 quarter hours beyond their last degree. At least one half of the respondents had had six or fewer years teaching experience and some experience in teaching other subject matter areas. Most (two thirds) taught in senior high schools where enrollments of more than one half of the schools were less than 1,000. Nearly one half of the respondents did not indicate that boys were a part of their program. Analysis of data showed that the respondents held quite positive beliefs concerning each of the six trends. For every trend, except programs for the handicapped, at least 70 percent felt that the home economics education programs were very important or moderately important. Fewer than five percent had negative feelings about any of the trends excepting programs for the handicapped and occupational education where 30 percent and 12 percent of the replies were negative and most often showed the feeling that respondents felt other groups were better qualified. The respondents showed a general willingness to support the trends with at least three fourths giving positive replies for every trend except programs for the handicapped and coeducational classes. The majority of the positive responses showed that the respondents were most interested in indirect types of support rather than active support. Negative replies most often showed that respondents believed other programs were more important, that they did not have time to support the trend, or that there was no need for the program in their community. Over one half of the respondents were willing to further prepare themselves for involvement in the six trends and were most interested in family life courses, occupational education and programs for the socio-economically disadvantaged. Special workshops was most often indicated as the preferred method of preparation. Negative replies showed that respondents were more interested in other areas or were already prepared. At least 80 percent of the respondents were willing to assume teaching responsibilities for every trend except occupational education and programs for the handicapped. Respondents often said they would teach in these trends only if they were given special preparation or if they were given time to prepare. Replies in the negative category most often indicated that the respondents were already involved or were more interested in other areas. Although nearly 70 percent of the respondents would assume leadership roles for family life, specialized semester, and coeducational classes, fewer than one half would take on this responsibility for occupational education and programs for the socio- economically disadvantaged and fewer than one fourth would lead programs for the handicapped. Respondents who replied negatively felt that they did not have the background or did not have the time or interest. The following conclusions were reached. 1. The majority of the respondents held favorable attitudes about the six trends. 2. Programs for the handicapped, the socio- economically disadvantaged, and occupational education followed similar patterns of acceptance and of respondents' willingness to be involved, while coeducational classes, specialized semester courses, family life courses were more accepted than the first three trends. Title: Teachers' beliefs and willingness to be involved with certain aspects of Oregon home economics education curriculum Author: Alexander, Capi Forsgren The purpose of this study was designed to answer 1. What are the beliefs and attitudes that Oregon home economics teachers hold about various new trends? 2. Are Oregon home economics teachers willing to support the various new trends? 3. Are Oregon home economics teachers willing to further prepare themselves to work with the trends? 4. Are Oregon home economics teachers willing to accept teaching responsibilities for the trends? 5. Are Oregon home economics teachers willing to assume leadership responsibilities for the trends? The six trends included in the study were related to programs for 1. The handicapped 2. The socio-economically disadvantaged 3. Occupational education 4. Coeducational classes 5. Specialized semester courses 6. Family life courses A questionnaire was constructed, validated, and sent to 394 home economics teachers in the State of Oregon to gain answers to the five questions as they related to the six trends. Of the questionnaires mailed out, 241 were returned and 160 (41 percent) were usable. Nearly one half of the respondents were 40 years of age or older. Approximately two thirds were married. Nearly 70 percent received their bachelor's degrees since 1940. Fewer than 15 percent of the respondents had master's degrees and over 80 percent of these were received since 1960. About one half of the teachers had taken from 1-42 quarter hours beyond their last degree. At least one half of the respondents had had six or fewer years teaching experience and some experience in teaching other subject matter areas. Most (two thirds) taught in senior high schools where enrollments of more than one half of the schools were less than 1,000. Nearly one half of the respondents did not indicate that boys were a part of their program. Analysis of data showed that the respondents held quite positive beliefs concerning each of the six trends. For every trend, except programs for the handicapped, at least 70 percent felt that the home economics education programs were very important or moderately important. Fewer than five percent had negative feelings about any of the trends excepting programs for the handicapped and occupational education where 30 percent and 12 percent of the replies were negative and most often showed the feeling that respondents felt other groups were better qualified. The respondents showed a general willingness to support the trends with at least three fourths giving positive replies for every trend except programs for the handicapped and coeducational classes. The majority of the positive responses showed that the respondents were most interested in indirect types of support rather than active support. Negative replies most often showed that respondents believed other programs were more important, that they did not have time to support the trend, or that there was no need for the program in their community. Over one half of the respondents were willing to further prepare themselves for involvement in the six trends and were most interested in family life courses, occupational education and programs for the socio-economically disadvantaged. Special workshops was most often indicated as the preferred method of preparation. Negative replies showed that respondents were more interested in other areas or were already prepared. At least 80 percent of the respondents were willing to assume teaching responsibilities for every trend except occupational education and programs for the handicapped. Respondents often said they would teach in these trends only if they were given special preparation or if they were given time to prepare. Replies in the negative category most often indicated that the respondents were already involved or were more interested in other areas. Although nearly 70 percent of the respondents would assume leadership roles for family life, specialized semester, and coeducational classes, fewer than one half would take on this responsibility for occupational education and programs for the socio- economically disadvantaged and fewer than one fourth would lead programs for the handicapped. Respondents who replied negatively felt that they did not have the background or did not have the time or interest. The following conclusions were reached. 1. The majority of the respondents held favorable attitudes about the six trends. 2. Programs for the handicapped, the socio- economically disadvantaged, and occupational education followed similar patterns of acceptance and of respondents' willingness to be involved, while coeducational classes, specialized semester courses, family life courses were more accepted than the first three trends. Close

• 9. [Article] An identification of and a comparison between trends in clothing and textiles in a selected group of colleges and universities

  The purpose of this study was to identify the most recent trends in Clothing and Textiles, to find whether any relationship existed between them, and whether there was difference of emphasis between large ...

  Citation × Citation Citation Abstract Copy Title: An identification of and a comparison between trends in clothing and textiles in a selected group of colleges and universities Author: Jacobsz, Maretha Stephanie The purpose of this study was to identify the most recent trends in Clothing and Textiles, to find whether any relationship existed between them, and whether there was difference of emphasis between large and small schools. The information about existing trends in Clothing and Textiles was collected from literature published in Clothing and Textiles Teachers Conference Reports and in Home Economics journals In addition, twenty catalogs from schools offering majors in Clothing and Textiles were analyzed for course content and educational objectives. The schools were divided in large and small categories according to the number of students enrolled as majors in Home Economics. From the literature it was concluded that the following four pairs of opposing trends existed: development of creative abilities, the development of skills; breadth in subject matter, depth in subject matter; family centeredness, subject matter orientation; general education, and professional education. A questionnaire was devised which tested the opposing trends in the four areas of Clothing and Textiles (clothing construction, clothing selection, textiles, and consumer economics). The face-validity was checked by nine faculty members experienced in the area of Clothing and Textiles, and rechecked by three Home Economics department heads and one textiles advisor, before it was finally sent out. The questions in the first part were indirect forced-choice type and referred only to the beginning courses. In Part II, the eight trends were independently listed and each department head was asked to rate her department as to the amount of emphasis given on the issues. The questionnaires were sent to 112 colleges and universities in the United States which offered Clothing and Textiles as a major in their Home Economics program. The chairmen of the departments were asked to participate and to return the completed questionnaires, of which 54 percent were returned, The returned questionnaires were statistically analyzed in the following way: means were determined for the trends for the indirect questions in Part I and for the ranking of trends in Part II in order to determine whether the trends existed and which were considered most important; Pearson r correlations were used to find the relationships between any of the trends in Part I, in Part II, and between Part I and Part II; t-test of mean differences between large and small schools were computed for each trend to find whether the difference was significant; and an analysis of variance was performed to find the significance of variance within the four areas of Clothing and Textiles in each of the trends. Data collected revealed that the mean scores of trends differed and that breadth in subject matter scored highest in both parts of the device. Significant correlations existed between all trends in the indirect questions, and between a few trends in the direct rating scale. The relations of creativity in the latter with breadth, depth, family centeredness and subject matter were the most significant. Correlations existed between some of the trends in both parts of the questionnaire, namely: breadth, family centeredness, between general and family centeredness, and between professional and depth. The opposing trends were in the negative direction. The significant relations of all trends in the beginning courses might be due to the tendency to teach the mastery of skills, breadth in subject matter with subject matter emphasis in the professional curricula. There were no significant differences in the mean scores between large and small schools but significant F ratios were found within the four areas of Clothing and Textiles for each pair of variables for the small schools and between one pair of variables for the large schools. An analysis of the course offerings, course content, and educational objectives were made from the catalog material. This revealed differences between small and large schools in general requirements for graduation and course offerings in Clothing and Textiles. Based on this information it was concluded that the small schools were more concerned with individual development of the students through a wide variety of general education courses, while the larger schools offered more courses within Clothing and Textiles and were more concerned with preparation for a professional career. Title: An identification of and a comparison between trends in clothing and textiles in a selected group of colleges and universities Author: Jacobsz, Maretha Stephanie The purpose of this study was to identify the most recent trends in Clothing and Textiles, to find whether any relationship existed between them, and whether there was difference of emphasis between large and small schools. The information about existing trends in Clothing and Textiles was collected from literature published in Clothing and Textiles Teachers Conference Reports and in Home Economics journals In addition, twenty catalogs from schools offering majors in Clothing and Textiles were analyzed for course content and educational objectives. The schools were divided in large and small categories according to the number of students enrolled as majors in Home Economics. From the literature it was concluded that the following four pairs of opposing trends existed: development of creative abilities, the development of skills; breadth in subject matter, depth in subject matter; family centeredness, subject matter orientation; general education, and professional education. A questionnaire was devised which tested the opposing trends in the four areas of Clothing and Textiles (clothing construction, clothing selection, textiles, and consumer economics). The face-validity was checked by nine faculty members experienced in the area of Clothing and Textiles, and rechecked by three Home Economics department heads and one textiles advisor, before it was finally sent out. The questions in the first part were indirect forced-choice type and referred only to the beginning courses. In Part II, the eight trends were independently listed and each department head was asked to rate her department as to the amount of emphasis given on the issues. The questionnaires were sent to 112 colleges and universities in the United States which offered Clothing and Textiles as a major in their Home Economics program. The chairmen of the departments were asked to participate and to return the completed questionnaires, of which 54 percent were returned, The returned questionnaires were statistically analyzed in the following way: means were determined for the trends for the indirect questions in Part I and for the ranking of trends in Part II in order to determine whether the trends existed and which were considered most important; Pearson r correlations were used to find the relationships between any of the trends in Part I, in Part II, and between Part I and Part II; t-test of mean differences between large and small schools were computed for each trend to find whether the difference was significant; and an analysis of variance was performed to find the significance of variance within the four areas of Clothing and Textiles in each of the trends. Data collected revealed that the mean scores of trends differed and that breadth in subject matter scored highest in both parts of the device. Significant correlations existed between all trends in the indirect questions, and between a few trends in the direct rating scale. The relations of creativity in the latter with breadth, depth, family centeredness and subject matter were the most significant. Correlations existed between some of the trends in both parts of the questionnaire, namely: breadth, family centeredness, between general and family centeredness, and between professional and depth. The opposing trends were in the negative direction. The significant relations of all trends in the beginning courses might be due to the tendency to teach the mastery of skills, breadth in subject matter with subject matter emphasis in the professional curricula. There were no significant differences in the mean scores between large and small schools but significant F ratios were found within the four areas of Clothing and Textiles for each pair of variables for the small schools and between one pair of variables for the large schools. An analysis of the course offerings, course content, and educational objectives were made from the catalog material. This revealed differences between small and large schools in general requirements for graduation and course offerings in Clothing and Textiles. Based on this information it was concluded that the small schools were more concerned with individual development of the students through a wide variety of general education courses, while the larger schools offered more courses within Clothing and Textiles and were more concerned with preparation for a professional career. Close

• 10. [Article] Height-related trends in structure and function of Douglas-fir foliage

  This dissertation investigated the impacts of tree height upon a range of physiological and structural characteristics of Douglas-fir foliage; relationships between structural and functional trends with ...

  Citation × Citation Citation Abstract Copy Title: Height-related trends in structure and function of Douglas-fir foliage Author: Woodruff, David R. This dissertation investigated the impacts of tree height upon a range of physiological and structural characteristics of Douglas-fir foliage; relationships between structural and functional trends with height; and compensatory mechanisms that mitigate height-related growth constraints. Height-related trends in foliar physiological and anatomical characteristics were examined both within trees as well as between trees of different heights. Emphasis was placed on discovering the mechanistic nature of the observed growth constraints and adaptive strategies. This research was conducted in the interest of enhancing our knowledge of the causes of age- and size-related decline in forest productivity. The research conducted for this dissertation explored several previously uninvestigated mechanisms for size-related reductions in forest productivity that are associated with tree foliar structure and function. Height-related trends in foliar turgor associated with the gravitational hydrostatic pressure gradient were identified as well as subsequent impacts on leaf and shoot morphology. Osmotic potential declined with height providing evidence of osmotic adjustment to offset the height-related decline in leaf turgor. This osmotic adjustment occurred only seasonally, and not during the spring when turgor maintenance is most important for leaf expansion. Gradients in leaf turgor were reflected in height-related trends in leaf and shoot morphology. Previous work has documented height-related trends in foliar morphological characteristics and earlier studies have examined osmotic adjustment as an adaptation to drought and salinity stress. Height-related trends in foliar morphological characteristics have typically been attributed to light gradients along vertical profiles. The work in this dissertation is the first to evaluate the effects of the gravitational component of water potential on the osmotic, morphological and growth characteristics of foliage along a height gradient in tall trees. Trends in leaf hydraulic efficiency and safety along a height gradient were examined, and correlations between changes in leaf hydraulic conductance (Kleaf) and changes in stomatal conductance (gs) were identified that provided evidence of a control mechanism for gs. A consistent relationship was discovered between changes in Kleaf and gs providing evidence that leaf tracheid embolism is associated with stomatal closure during periods of declining water availability. Hydraulic vulnerability curves of foliage collected at different heights indicated that increased height is correlated with reduced hydraulic efficiency and increased hydraulic safety. These opposing trends suggest the existence of a compensatory mechanism in foliage that functions to reduce hydraulic vulnerability at the expense of transport capacity. The research in this dissertation is the first to examine the dynamic relationships between leaf hydraulics and stomatal behavior in temperate conifers, and the first to examine how these characteristics are affected by tree height. Height-related trends in leaf xylem anatomical characteristics were examined and strong correlations were identified between these anatomical characteristics and the patterns of leaf hydraulic efficiency and safety that were observed in previous work for this dissertation. Theoretical estimates of leaf hydraulic efficiency (Kleaf-theoretical) based upon the Hagen-Pouseille equation and measured leaf tracheid anatomical characteristics were strongly correlated with laboratory measurements of Kleaf, providing further evidence of a causal relationship between height-related trends in both leaf tracheid anatomical properties and leaf hydraulic function. Earlier studies have documented connections between leaf anatomical characteristics and leaf physiological characteristics such as correlations between leaf architecture and gas exchange and leaf architecture and transport efficiency. The research in this dissertation however, is the first to examine the impact of tree height on leaf anatomical characteristics and associated shoot physiological properties. Trends in gas-exchange along a height gradient were identified, independent of the immediate effects of path length and gravitational resistance. Photosynthesis under ambient [CO2] declined with height in a manner that was consistent with height-related trends in mesophyll anatomy and independent of leaf nitrogen content. Analyses of mesophyll resistance from assimilation versus internal CO2 concentration (A-Ci) curves indicated that height-related trends in mesophyll resistance were correlated with trends in both photosynthesis and mesophyll anatomy along a height gradient. Analyses of integrated and instantaneous water use efficiency indicated that height-related trends in integrated water use efficiency are attributable to the effects of path length and gravity on stomatal behavior as opposed to a height-related trend in intrinsic foliar properties. The research in this dissertation is the first to isolate the influence of height-related trends in foliar structure on different gas exchange properties such as assimilation and mesophyll conductance, independent of the direct effects of vertical gradients in xylem tension on stomatal and photosynthetic physiology. Title: Height-related trends in structure and function of Douglas-fir foliage Author: Woodruff, David R. This dissertation investigated the impacts of tree height upon a range of physiological and structural characteristics of Douglas-fir foliage; relationships between structural and functional trends with height; and compensatory mechanisms that mitigate height-related growth constraints. Height-related trends in foliar physiological and anatomical characteristics were examined both within trees as well as between trees of different heights. Emphasis was placed on discovering the mechanistic nature of the observed growth constraints and adaptive strategies. This research was conducted in the interest of enhancing our knowledge of the causes of age- and size-related decline in forest productivity. The research conducted for this dissertation explored several previously uninvestigated mechanisms for size-related reductions in forest productivity that are associated with tree foliar structure and function. Height-related trends in foliar turgor associated with the gravitational hydrostatic pressure gradient were identified as well as subsequent impacts on leaf and shoot morphology. Osmotic potential declined with height providing evidence of osmotic adjustment to offset the height-related decline in leaf turgor. This osmotic adjustment occurred only seasonally, and not during the spring when turgor maintenance is most important for leaf expansion. Gradients in leaf turgor were reflected in height-related trends in leaf and shoot morphology. Previous work has documented height-related trends in foliar morphological characteristics and earlier studies have examined osmotic adjustment as an adaptation to drought and salinity stress. Height-related trends in foliar morphological characteristics have typically been attributed to light gradients along vertical profiles. The work in this dissertation is the first to evaluate the effects of the gravitational component of water potential on the osmotic, morphological and growth characteristics of foliage along a height gradient in tall trees. Trends in leaf hydraulic efficiency and safety along a height gradient were examined, and correlations between changes in leaf hydraulic conductance (Kleaf) and changes in stomatal conductance (gs) were identified that provided evidence of a control mechanism for gs. A consistent relationship was discovered between changes in Kleaf and gs providing evidence that leaf tracheid embolism is associated with stomatal closure during periods of declining water availability. Hydraulic vulnerability curves of foliage collected at different heights indicated that increased height is correlated with reduced hydraulic efficiency and increased hydraulic safety. These opposing trends suggest the existence of a compensatory mechanism in foliage that functions to reduce hydraulic vulnerability at the expense of transport capacity. The research in this dissertation is the first to examine the dynamic relationships between leaf hydraulics and stomatal behavior in temperate conifers, and the first to examine how these characteristics are affected by tree height. Height-related trends in leaf xylem anatomical characteristics were examined and strong correlations were identified between these anatomical characteristics and the patterns of leaf hydraulic efficiency and safety that were observed in previous work for this dissertation. Theoretical estimates of leaf hydraulic efficiency (Kleaf-theoretical) based upon the Hagen-Pouseille equation and measured leaf tracheid anatomical characteristics were strongly correlated with laboratory measurements of Kleaf, providing further evidence of a causal relationship between height-related trends in both leaf tracheid anatomical properties and leaf hydraulic function. Earlier studies have documented connections between leaf anatomical characteristics and leaf physiological characteristics such as correlations between leaf architecture and gas exchange and leaf architecture and transport efficiency. The research in this dissertation however, is the first to examine the impact of tree height on leaf anatomical characteristics and associated shoot physiological properties. Trends in gas-exchange along a height gradient were identified, independent of the immediate effects of path length and gravitational resistance. Photosynthesis under ambient [CO2] declined with height in a manner that was consistent with height-related trends in mesophyll anatomy and independent of leaf nitrogen content. Analyses of mesophyll resistance from assimilation versus internal CO2 concentration (A-Ci) curves indicated that height-related trends in mesophyll resistance were correlated with trends in both photosynthesis and mesophyll anatomy along a height gradient. Analyses of integrated and instantaneous water use efficiency indicated that height-related trends in integrated water use efficiency are attributable to the effects of path length and gravity on stomatal behavior as opposed to a height-related trend in intrinsic foliar properties. The research in this dissertation is the first to isolate the influence of height-related trends in foliar structure on different gas exchange properties such as assimilation and mesophyll conductance, independent of the direct effects of vertical gradients in xylem tension on stomatal and photosynthetic physiology. Close