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• 151. [Article] 3-D modelling of IC interconnect using OpenAccess and Art of Illusion

  In search of higher speed and integration, the integrated circuit (IC) technology is scaling down. The total on-chip interconnect length is increasing exponentially. In fact, interconnect takes up the ...

  Citation × Citation Citation Abstract Copy Title: 3-D modelling of IC interconnect using OpenAccess and Art of Illusion Author: Jamadagni, Navaneeth Prasannakumar Year: 2010 In search of higher speed and integration, the integrated circuit (IC) technology is scaling down. The total on-chip interconnect length is increasing exponentially. In fact, interconnect takes up the most part of the total chip area. The parasitics associated with these interconnect have significant impact on the circuit performance. Some of the effects of parasitics include cross talk, voltage drop and high current density. These issues can result in cross-talk induced functional failure and failures due to IR drop and electro-migration. This has resulted in interconnect- driven design trend in state-of-the-art integrated circuits. Reliability analysis, that includes simulating the effects of parasitics for voltage drop, current density, has become one of the most important steps in the VLSI design flow. Most of the CAD/EDA tools available, map these analysis results two dimensionally. Al- though this helps the designer, providing a three dimensional view of these results is highly desirable when dealing with complex circuits. In pursuit of visualizing reliability analysis results three dimensionally, as a first step, this work presents a tool that can visualize IC interconnect three di- mensionally. Throughout the course of this research open source tools were used to achieve the objective. In this work the circuit layout is stored as an OpenAc- cess database. A C++ program reads the design information using OpenAccess API and converts it to the .OBJ file format. Art of Illusion, an open source 3D modeling and rendering tool, reads this .OBJ file and models the IC interconnect three-dimensionally. In addition, Eclipse, an open source java IDE is used as a development platform. The tool presented has the capability to zoom in, zoom out and pan in real time. Title: 3-D modelling of IC interconnect using OpenAccess and Art of Illusion Author: Jamadagni, Navaneeth Prasannakumar Year: 2010 In search of higher speed and integration, the integrated circuit (IC) technology is scaling down. The total on-chip interconnect length is increasing exponentially. In fact, interconnect takes up the most part of the total chip area. The parasitics associated with these interconnect have significant impact on the circuit performance. Some of the effects of parasitics include cross talk, voltage drop and high current density. These issues can result in cross-talk induced functional failure and failures due to IR drop and electro-migration. This has resulted in interconnect- driven design trend in state-of-the-art integrated circuits. Reliability analysis, that includes simulating the effects of parasitics for voltage drop, current density, has become one of the most important steps in the VLSI design flow. Most of the CAD/EDA tools available, map these analysis results two dimensionally. Al- though this helps the designer, providing a three dimensional view of these results is highly desirable when dealing with complex circuits. In pursuit of visualizing reliability analysis results three dimensionally, as a first step, this work presents a tool that can visualize IC interconnect three di- mensionally. Throughout the course of this research open source tools were used to achieve the objective. In this work the circuit layout is stored as an OpenAc- cess database. A C++ program reads the design information using OpenAccess API and converts it to the .OBJ file format. Art of Illusion, an open source 3D modeling and rendering tool, reads this .OBJ file and models the IC interconnect three-dimensionally. In addition, Eclipse, an open source java IDE is used as a development platform. The tool presented has the capability to zoom in, zoom out and pan in real time. Close

• 152. [Article] Phylogeographic Patterns and Intervarietal Relationships within Lupinus lepidus: Morphological Differences, Genetic Similarities

  Lupinus lepidus (Fabaceae) contains many morphologically divergent varieties and was restricted in its range during the last period of glaciation. A combination of phylogenetic (with the trnDT and LEGCYC1A ...

  Citation × Citation Citation Abstract Copy Title: Phylogeographic Patterns and Intervarietal Relationships within Lupinus lepidus: Morphological Differences, Genetic Similarities Author: Weitemier, Kevin Allen Year: 2010 Lupinus lepidus (Fabaceae) contains many morphologically divergent varieties and was restricted in its range during the last period of glaciation. A combination of phylogenetic (with the trnDT and LEGCYC1A loci) and population genetics approaches (with microsatellites and LEGCYC1A are used here to characterize intervarietal relationships and examine hypotheses of recolonization of areas in the Pacific Northwest affected by glaciation. Sequenced loci are not found to form a clade exclusive to L. lepidus, nor are any of the varieties found to form clades. Population genetics analyses reveal only negligible genetic structure within L. lepidus, with the majority of variation being found within populations. Isolation-by-distance analysis reveals some correlation between population genetic distances and geographic distance. Microsatellite and sequence results are consistent with a scenario whereby the Oregon and Washington regions were rapidly colonized from the south, with independent invasions along the eastern and western sides of the Cascade Mountains. A predicted disjunction between northern and southern populations is found within the microsatellite data but not the sequence data, suggesting that northern populations were recolonized via a process involving the spread of novel microsatellite mutations, perhaps through the persistence of a glacial refuge isolated from southern populations. Varieties are not shown to be genetically isolated, and are interpreted as representing ecotypes, with local selection outpacing the effects of migration. Title: Phylogeographic Patterns and Intervarietal Relationships within Lupinus lepidus: Morphological Differences, Genetic Similarities Author: Weitemier, Kevin Allen Year: 2010 Lupinus lepidus (Fabaceae) contains many morphologically divergent varieties and was restricted in its range during the last period of glaciation. A combination of phylogenetic (with the trnDT and LEGCYC1A loci) and population genetics approaches (with microsatellites and LEGCYC1A are used here to characterize intervarietal relationships and examine hypotheses of recolonization of areas in the Pacific Northwest affected by glaciation. Sequenced loci are not found to form a clade exclusive to L. lepidus, nor are any of the varieties found to form clades. Population genetics analyses reveal only negligible genetic structure within L. lepidus, with the majority of variation being found within populations. Isolation-by-distance analysis reveals some correlation between population genetic distances and geographic distance. Microsatellite and sequence results are consistent with a scenario whereby the Oregon and Washington regions were rapidly colonized from the south, with independent invasions along the eastern and western sides of the Cascade Mountains. A predicted disjunction between northern and southern populations is found within the microsatellite data but not the sequence data, suggesting that northern populations were recolonized via a process involving the spread of novel microsatellite mutations, perhaps through the persistence of a glacial refuge isolated from southern populations. Varieties are not shown to be genetically isolated, and are interpreted as representing ecotypes, with local selection outpacing the effects of migration. Close

• 153. [Article] Effects of the nerve during the dedifferentiative phase of limb regeneration in the Mexican axolotl, Ambystoma Iilexicanum

  It is known that nerves are particularly critical during the early or dedifferentiative phase of limb regeneration. During this period in the innervated limb, cells just proximal to the amputation surface ...

  Citation × Citation Citation Abstract Copy Title: Effects of the nerve during the dedifferentiative phase of limb regeneration in the Mexican axolotl, Ambystoma Iilexicanum Author: Wald, Roberta Gail Year: 1974 It is known that nerves are particularly critical during the early or dedifferentiative phase of limb regeneration. During this period in the innervated limb, cells just proximal to the amputation surface dedifferentiate, migrate to the limb tip, and undergo mitosis. These processes give rise to a population of undifferentiated mesenchymatous cells capable of redifferentiating into the missing components of the newly forming regenerate. The consequences of denervation stand in stark contrast to the normal events occurring in the innervated limb, because neither a blastema nor a regenerate forms. Results from this study indicate that during the early portion of the dedifferentiative phase in regenerates less than 2 3/4, days old the nerve apparently has little or no effect on the internal stump tissues. Of considerable interest in this regard is this study's documentation of a lack of neural influence on DNA synthesis and thus the cell cycle during the early dedifferentiative phase. Subsequently, during a transition period represented by 2 3/4 to 5 1/2 days regenerates there is some evidence for a neural influence on DNA synthesis in cells of the limb stump. Finally, on days 6 through 8, DNA synthesis is clearly nerve dependent. Since DNA synthesis is a prerequisite for mitosis, the depressed synthesis in a denervated limb precludes mitotic activity during the nerve-dependent, later portion of the dedifferentiative phase. Therefore, this research supports the idea that during the late dedifferentiative phase, including mound and early cone blastemal stages, there is a neural influence on the G1 or S phases of the cell cycle. This conclusion thereby makes progress toward explaining earlier observations of depressed mitotic activity during this period. Title: Effects of the nerve during the dedifferentiative phase of limb regeneration in the Mexican axolotl, Ambystoma Iilexicanum Author: Wald, Roberta Gail Year: 1974 It is known that nerves are particularly critical during the early or dedifferentiative phase of limb regeneration. During this period in the innervated limb, cells just proximal to the amputation surface dedifferentiate, migrate to the limb tip, and undergo mitosis. These processes give rise to a population of undifferentiated mesenchymatous cells capable of redifferentiating into the missing components of the newly forming regenerate. The consequences of denervation stand in stark contrast to the normal events occurring in the innervated limb, because neither a blastema nor a regenerate forms. Results from this study indicate that during the early portion of the dedifferentiative phase in regenerates less than 2 3/4, days old the nerve apparently has little or no effect on the internal stump tissues. Of considerable interest in this regard is this study's documentation of a lack of neural influence on DNA synthesis and thus the cell cycle during the early dedifferentiative phase. Subsequently, during a transition period represented by 2 3/4 to 5 1/2 days regenerates there is some evidence for a neural influence on DNA synthesis in cells of the limb stump. Finally, on days 6 through 8, DNA synthesis is clearly nerve dependent. Since DNA synthesis is a prerequisite for mitosis, the depressed synthesis in a denervated limb precludes mitotic activity during the nerve-dependent, later portion of the dedifferentiative phase. Therefore, this research supports the idea that during the late dedifferentiative phase, including mound and early cone blastemal stages, there is a neural influence on the G1 or S phases of the cell cycle. This conclusion thereby makes progress toward explaining earlier observations of depressed mitotic activity during this period. Close

• 154. [Article] The effects of urban-rural life histories of the aged on urban adaptation

  Among the major interests of students of urbanism and urbanization in the United States have been the understanding and explication of differences between urban and rural segments of American society. ...

  Citation × Citation Citation Abstract Copy Title: The effects of urban-rural life histories of the aged on urban adaptation Author: DeShane, Michael R. Year: 1977 Among the major interests of students of urbanism and urbanization in the United States have been the understanding and explication of differences between urban and rural segments of American society. Coupled with this has been an attempt to theoretically delineate the effects of these differences on the social psychological adjustment of urban and rural inhabitants. The culmination of this work in sociology is to be found in Wirth's (1938) essay "Urbanism as a Way of Life." Wirth identified three major differences between urban and rural lifestyles which have been the impetus for considerable research and controversy. The three major differences identified by Wirth are: 1. the weakening of primary relationships, 2. the development of a distinctly urban personality characterized by rationality, utility and adaptability, and 3. the development of a community based on interest rather than locality. Research has, to date, been equivocal in its support or rejection of these differences. This dissertation represents another attempt to test what might be called the "Wirthian hypotheses II but with a major departure from other attempts. Rather than using current urban or rural residence as the major independent variables, urban or rural residences at age 16 are used. The research was conducted using data from two sample surveys, one a national sample (the "General Social Survey" conducted by NORC in the Spring of 1975), and one a sample of Portland, Oregon's 65 and over population (the "Supplementary Security Income Survey" conducted by the Institute on Aging in 1975). The research was limited to older persons 60 years of age and over. This dissertation, then, is an attempt to gauge the effects of residential history on the three central hypotheses derived from the earlier formulations of Louis Wirth. The three research hypotheses are: 1. Lifelong urban residents are likely to exhibit less intense primary group/ties than are lifelong rural residents or urban migrants. 2. Lifelong urban residents are more likely to develop adaptable and individualistic personality structures than are lifelong rural residents or urban migrants. 3. Lifelong urban residents are less likely to maintain a community based upon proximity than are lifelong rural residents or urban migrants. Title: The effects of urban-rural life histories of the aged on urban adaptation Author: DeShane, Michael R. Year: 1977 Among the major interests of students of urbanism and urbanization in the United States have been the understanding and explication of differences between urban and rural segments of American society. Coupled with this has been an attempt to theoretically delineate the effects of these differences on the social psychological adjustment of urban and rural inhabitants. The culmination of this work in sociology is to be found in Wirth's (1938) essay "Urbanism as a Way of Life." Wirth identified three major differences between urban and rural lifestyles which have been the impetus for considerable research and controversy. The three major differences identified by Wirth are: 1. the weakening of primary relationships, 2. the development of a distinctly urban personality characterized by rationality, utility and adaptability, and 3. the development of a community based on interest rather than locality. Research has, to date, been equivocal in its support or rejection of these differences. This dissertation represents another attempt to test what might be called the "Wirthian hypotheses II but with a major departure from other attempts. Rather than using current urban or rural residence as the major independent variables, urban or rural residences at age 16 are used. The research was conducted using data from two sample surveys, one a national sample (the "General Social Survey" conducted by NORC in the Spring of 1975), and one a sample of Portland, Oregon's 65 and over population (the "Supplementary Security Income Survey" conducted by the Institute on Aging in 1975). The research was limited to older persons 60 years of age and over. This dissertation, then, is an attempt to gauge the effects of residential history on the three central hypotheses derived from the earlier formulations of Louis Wirth. The three research hypotheses are: 1. Lifelong urban residents are likely to exhibit less intense primary group/ties than are lifelong rural residents or urban migrants. 2. Lifelong urban residents are more likely to develop adaptable and individualistic personality structures than are lifelong rural residents or urban migrants. 3. Lifelong urban residents are less likely to maintain a community based upon proximity than are lifelong rural residents or urban migrants. Close

• 155. [Article] Water Quality Within East Portland Terraces

  Groundwater from thirty-three wells which are randomly distributed within 42 square miles of the residential, agricultural and industrial area of East Portland Terraces have been analyzed. The area is ...

  Citation × Citation Citation Abstract Copy Title: Water Quality Within East Portland Terraces Author: Tawfik, Fouad Mohamed Year: 1974 Groundwater from thirty-three wells which are randomly distributed within 42 square miles of the residential, agricultural and industrial area of East Portland Terraces have been analyzed. The area is moderately wet with an annual precipitation of about 37 inches. Residual and transported sediments from different sources, dominantly volcanic, comprise the subsurface lithology. The sedimentary units that were deposited by means of rivers and lakes have filled an original structural and erosional valley in the area. This relatively unconsolidated valley filling is about 900 feet of predominantly lenticular, stratified and cross-bedded lenses of clay, silt, sand, gravel, cobbles and boulders. The topsoil throughout the area has generally similar mechanical characteristics with good drainage. Due to the physical characteristics of the rocks, soils and topography, the area has an open hydraulic system that contains a substantial amount of usable subsurface water. The wells sampled are relatively shallow and their aquifers receive their main recharge from percolated rainfall water. Most of these aquifers occur within the Troutdale Formation rock unit. The major sources of the dissolved elements in the water are the rock units and the organic material of present or buried soils. These sources, along with mixing of water through subsurface migration, created similar compositions in all the tested aquifers, except nitrates and probably phosphates which show a general minor change from east to west, generally correlative with population density. These major mechanisms, man-made activities and/or analytical errors produced only minor differences in the analyses. No major change was detected which could be related to the minor lithologic differences or of the small changes in soils. Comparison with a few older analyses did not indicate a change with time. Alkaline earths in the water exceeded alkalies and weak acids alee exceeded strong ones. This meteoric ground water is bicarbonaceous-siliceous and is good for general use. It is diluted, neutral, fresh, moderately hard and has low salinity hazard. Title: Water Quality Within East Portland Terraces Author: Tawfik, Fouad Mohamed Year: 1974 Groundwater from thirty-three wells which are randomly distributed within 42 square miles of the residential, agricultural and industrial area of East Portland Terraces have been analyzed. The area is moderately wet with an annual precipitation of about 37 inches. Residual and transported sediments from different sources, dominantly volcanic, comprise the subsurface lithology. The sedimentary units that were deposited by means of rivers and lakes have filled an original structural and erosional valley in the area. This relatively unconsolidated valley filling is about 900 feet of predominantly lenticular, stratified and cross-bedded lenses of clay, silt, sand, gravel, cobbles and boulders. The topsoil throughout the area has generally similar mechanical characteristics with good drainage. Due to the physical characteristics of the rocks, soils and topography, the area has an open hydraulic system that contains a substantial amount of usable subsurface water. The wells sampled are relatively shallow and their aquifers receive their main recharge from percolated rainfall water. Most of these aquifers occur within the Troutdale Formation rock unit. The major sources of the dissolved elements in the water are the rock units and the organic material of present or buried soils. These sources, along with mixing of water through subsurface migration, created similar compositions in all the tested aquifers, except nitrates and probably phosphates which show a general minor change from east to west, generally correlative with population density. These major mechanisms, man-made activities and/or analytical errors produced only minor differences in the analyses. No major change was detected which could be related to the minor lithologic differences or of the small changes in soils. Comparison with a few older analyses did not indicate a change with time. Alkaline earths in the water exceeded alkalies and weak acids alee exceeded strong ones. This meteoric ground water is bicarbonaceous-siliceous and is good for general use. It is diluted, neutral, fresh, moderately hard and has low salinity hazard. Close

• 156. [Article] Chicanos in Oregon: An historical overview

  Spaniards were the first Europeans to explore the Pacific Northwest coastline, but the only evidence of these early visits is a sprinkling of Spanish place names commemorating the intrepid voyagers. The ...

  Citation × Citation Citation Abstract Copy Title: Chicanos in Oregon: An historical overview Author: Slatta, Richard Wayne Year: 1974 Spaniards were the first Europeans to explore the Pacific Northwest coastline, but the only evidence of these early visits is a sprinkling of Spanish place names commemorating the intrepid voyagers. The more than four centuries of recorded history since that time are nearly devoid, of references to Spanish-speaking people, especially Mexicans and Americans of Mexican descent (Chicanos). Even the heavy influx of Chicano migrant farm workers in the 1950’s and 1960's failed to attract the attention of historians or social science researchers. By 1970, the Spanish-language population had become Oregon's largest ethnic minority and was exerting influence in most areas of state life. This study documents the depth and diversity of Oregon’s Chicano community and provides an historical context for the movement of Spanish-speaking people into the state. Even in the strongly Anglo-American milieu of the Northwest, Chicanos have retained their unique blend of Mexican and American cultural and linguistic characteristics. Through social clubs, cultural centers, economic and political organizations and an independent college, Chicanos in Oregon are preserving and proclaiming their heritage. Hopefully, this study will aid Anglo Americans in understanding and accepting cultural differences without prejudice or animosity, and help Chicanos to better appreciate their position in the state. The dominantly oral tradition of the Chicano coupled with the dearth of standard documentation, primary and secondary, required reliance upon interviews and conversations and generalization upon limited data. Research revealed that the migrant farm worker image of the Chicano has become obsolete as the Oregon population has become settled and primarily urban. If this study provides a frame of reference for and generates interest in further investigation of the migration of Chicanos into Oregon, it will have served its purpose. Title: Chicanos in Oregon: An historical overview Author: Slatta, Richard Wayne Year: 1974 Spaniards were the first Europeans to explore the Pacific Northwest coastline, but the only evidence of these early visits is a sprinkling of Spanish place names commemorating the intrepid voyagers. The more than four centuries of recorded history since that time are nearly devoid, of references to Spanish-speaking people, especially Mexicans and Americans of Mexican descent (Chicanos). Even the heavy influx of Chicano migrant farm workers in the 1950’s and 1960's failed to attract the attention of historians or social science researchers. By 1970, the Spanish-language population had become Oregon's largest ethnic minority and was exerting influence in most areas of state life. This study documents the depth and diversity of Oregon’s Chicano community and provides an historical context for the movement of Spanish-speaking people into the state. Even in the strongly Anglo-American milieu of the Northwest, Chicanos have retained their unique blend of Mexican and American cultural and linguistic characteristics. Through social clubs, cultural centers, economic and political organizations and an independent college, Chicanos in Oregon are preserving and proclaiming their heritage. Hopefully, this study will aid Anglo Americans in understanding and accepting cultural differences without prejudice or animosity, and help Chicanos to better appreciate their position in the state. The dominantly oral tradition of the Chicano coupled with the dearth of standard documentation, primary and secondary, required reliance upon interviews and conversations and generalization upon limited data. Research revealed that the migrant farm worker image of the Chicano has become obsolete as the Oregon population has become settled and primarily urban. If this study provides a frame of reference for and generates interest in further investigation of the migration of Chicanos into Oregon, it will have served its purpose. Close

• 157. [Article] Cross-Species Array Comparative Genomic Hybridization Identifies Novel Oncogenic Events in Zebrafish and Human Embryonal Rhabdomyosarcoma

  Human cancer genomes are highly complex, making it challenging to identify specific drivers of cancer growth, progression, and tumor maintenance. To bypass this obstacle, we have applied array comparative ...

  Citation × Citation Citation Abstract Copy Title: Cross-Species Array Comparative Genomic Hybridization Identifies Novel Oncogenic Events in Zebrafish and Human Embryonal Rhabdomyosarcoma Author: Chen, Eleanor Y., Dobrinski, Kimberly P., Brown, Kim H., Clagg, Ryan, Edelman, Elena, Ignatius, Myron S., Chen, Jin Yun Helen, Brockmann, Jillian, Nielsen, G. Petur, Ramaswamy, Sridhar, Keller, Charles, Lee, Charles, Langenau, David M. Year: 2013 Human cancer genomes are highly complex, making it challenging to identify specific drivers of cancer growth, progression, and tumor maintenance. To bypass this obstacle, we have applied array comparative genomic hybridization (array CGH) to zebrafish embryonal rhabdomyosaroma (ERMS) and utilized cross-species comparison to rapidly identify genomic copy number aberrations and novel candidate oncogenes in human disease. Zebrafish ERMS contain small, focal regions of low-copy amplification. These same regions were commonly amplified in human disease. For example, 16 of 19 chromosomal gains identified in zebrafish ERMS also exhibited focal, low-copy gains in human disease. Genes found in amplified genomic regions were assessed for functional roles in promoting continued tumor growth in human and zebrafish ERMS – identifying critical genes associated with tumor maintenance. Knockdown studies identified important roles for Cyclin D2 (CCND2), Homeobox Protein C6 (HOXC6) and PlexinA1 (PLXNA1) in human ERMS cell proliferation. PLXNA1 knockdown also enhanced differentiation, reduced migration, and altered anchorage-independent growth. By contrast, chemical inhibition of vascular endothelial growth factor (VEGF) signaling reduced angiogenesis and tumor size in ERMS-bearing zebrafish. Importantly, VEGFA expression correlated with poor clinical outcome in patients with ERMS, implicating inhibitors of the VEGF pathway as a promising therapy for improving patient survival. Our results demonstrate the utility of array CGH and cross-species comparisons to identify candidate oncogenes essential for the pathogenesis of human cancer. Title: Cross-Species Array Comparative Genomic Hybridization Identifies Novel Oncogenic Events in Zebrafish and Human Embryonal Rhabdomyosarcoma Author: Chen, Eleanor Y., Dobrinski, Kimberly P., Brown, Kim H., Clagg, Ryan, Edelman, Elena, Ignatius, Myron S., Chen, Jin Yun Helen, Brockmann, Jillian, Nielsen, G. Petur, Ramaswamy, Sridhar, Keller, Charles, Lee, Charles, Langenau, David M. Year: 2013 Human cancer genomes are highly complex, making it challenging to identify specific drivers of cancer growth, progression, and tumor maintenance. To bypass this obstacle, we have applied array comparative genomic hybridization (array CGH) to zebrafish embryonal rhabdomyosaroma (ERMS) and utilized cross-species comparison to rapidly identify genomic copy number aberrations and novel candidate oncogenes in human disease. Zebrafish ERMS contain small, focal regions of low-copy amplification. These same regions were commonly amplified in human disease. For example, 16 of 19 chromosomal gains identified in zebrafish ERMS also exhibited focal, low-copy gains in human disease. Genes found in amplified genomic regions were assessed for functional roles in promoting continued tumor growth in human and zebrafish ERMS – identifying critical genes associated with tumor maintenance. Knockdown studies identified important roles for Cyclin D2 (CCND2), Homeobox Protein C6 (HOXC6) and PlexinA1 (PLXNA1) in human ERMS cell proliferation. PLXNA1 knockdown also enhanced differentiation, reduced migration, and altered anchorage-independent growth. By contrast, chemical inhibition of vascular endothelial growth factor (VEGF) signaling reduced angiogenesis and tumor size in ERMS-bearing zebrafish. Importantly, VEGFA expression correlated with poor clinical outcome in patients with ERMS, implicating inhibitors of the VEGF pathway as a promising therapy for improving patient survival. Our results demonstrate the utility of array CGH and cross-species comparisons to identify candidate oncogenes essential for the pathogenesis of human cancer. Close

• 158. [Article] North America. Climate Change 2007: Impacts, Adaptation and Vulnerability

  The United States (U.S.) and Canada will experience climate changes through direct effects of local changes (e.g., temperature, precipitation and extreme weather events), as well as through indirect effects, ...

  Citation × Citation Citation Abstract Copy Title: North America. Climate Change 2007: Impacts, Adaptation and Vulnerability Author: Fields, Christopher B., Mortsch, Linda D., Brklacich, Michael, Forbes, Donald L., Kovacs, Paul, Patz, Jonathan A., Running, Steven W., Scott, Michael J., Andrey, Jean, Cayan, Dan, Demuth, Mike, Hamlet, Alan, Jones, Gregory, Mills, Evan, Mills, Scott, Minns, Charles K., Sailor, David J., Saunders, Mark, Scott, Daniel, Solecki, William Year: 2007 The United States (U.S.) and Canada will experience climate changes through direct effects of local changes (e.g., temperature, precipitation and extreme weather events), as well as through indirect effects, transmitted among regions by interconnected economies and migrations of humans and other species. Variations in wealth and geography, however, lead to an uneven distribution of likely impacts, vulnerabilities and capacities to adapt. This chapter reviews and synthesises the state of knowledge on direct and indirect impacts, vulnerability and adaptations for North America (comprising Canada and the U.S). Hawaii and other U.S. protectorates are discussed in Chapter 16 on Small Islands, and Mexico and Central America are treated in Chapter 13 on Latin America. Chapter 15, Polar Regions, covers high-latitude issues and peoples. Title: North America. Climate Change 2007: Impacts, Adaptation and Vulnerability Author: Fields, Christopher B., Mortsch, Linda D., Brklacich, Michael, Forbes, Donald L., Kovacs, Paul, Patz, Jonathan A., Running, Steven W., Scott, Michael J., Andrey, Jean, Cayan, Dan, Demuth, Mike, Hamlet, Alan, Jones, Gregory, Mills, Evan, Mills, Scott, Minns, Charles K., Sailor, David J., Saunders, Mark, Scott, Daniel, Solecki, William Year: 2007 The United States (U.S.) and Canada will experience climate changes through direct effects of local changes (e.g., temperature, precipitation and extreme weather events), as well as through indirect effects, transmitted among regions by interconnected economies and migrations of humans and other species. Variations in wealth and geography, however, lead to an uneven distribution of likely impacts, vulnerabilities and capacities to adapt. This chapter reviews and synthesises the state of knowledge on direct and indirect impacts, vulnerability and adaptations for North America (comprising Canada and the U.S). Hawaii and other U.S. protectorates are discussed in Chapter 16 on Small Islands, and Mexico and Central America are treated in Chapter 13 on Latin America. Chapter 15, Polar Regions, covers high-latitude issues and peoples. Close

• 159. [Article] Transient flow inverse study calculation of unsaturated permeability of wood

  One of the major processes in lumber industry is wood drying. This process consumes large amounts of energy and capital, and due to the length of time it takes, it acts as a governing factor in lumber ...

  Citation × Citation Citation Abstract Copy Title: Transient flow inverse study calculation of unsaturated permeability of wood Author: Piroozmandi, Farid Year: 1985 One of the major processes in lumber industry is wood drying. This process consumes large amounts of energy and capital, and due to the length of time it takes, it acts as a governing factor in lumber production levels. Development of improvements in processes and equipment used in wood drying can be expedited through computer simulation of various drying procedures. These numerical simulations depend on the accuracy of numerical models representing wood transport properties, including functional dependency of liquid permeability through wood with respect to local saturation level. Data available in the literature mainly represent wood permeability properties at fully saturated levels. This is an indication of steady state flow methods used in determining these values which are based on wide spread use of similar methods utilized in studies on fluid flow through soil. This research determines unsaturated wood permeability using transient liquid flow methods that are more representative of actual drying process. Initially saturated wood samples are spun in a low speed centrifuge to induce liquid migration through the cell structures. Transient local moisture profiles along the sample are measured using a scanning gamma ray densitometer. Numerical integration and curve fitting procedures are used to process these data. Finally, utilizing liquid continuity equation the functional dependency of permeability with respect to saturation is calculated. Some permeability results appear to be reasonable when compared with actual wood behavior during drying. Measurement procedures prove to yield accurate results for moisture content and saturation levels in wood with less than 5% relative error in average saturation level of .75. However, due to natural inhomogeneities in wood cellular structure, the final calculated results for unsaturated permeability show high levels of uncertainty (up to 112% relative error). Title: Transient flow inverse study calculation of unsaturated permeability of wood Author: Piroozmandi, Farid Year: 1985 One of the major processes in lumber industry is wood drying. This process consumes large amounts of energy and capital, and due to the length of time it takes, it acts as a governing factor in lumber production levels. Development of improvements in processes and equipment used in wood drying can be expedited through computer simulation of various drying procedures. These numerical simulations depend on the accuracy of numerical models representing wood transport properties, including functional dependency of liquid permeability through wood with respect to local saturation level. Data available in the literature mainly represent wood permeability properties at fully saturated levels. This is an indication of steady state flow methods used in determining these values which are based on wide spread use of similar methods utilized in studies on fluid flow through soil. This research determines unsaturated wood permeability using transient liquid flow methods that are more representative of actual drying process. Initially saturated wood samples are spun in a low speed centrifuge to induce liquid migration through the cell structures. Transient local moisture profiles along the sample are measured using a scanning gamma ray densitometer. Numerical integration and curve fitting procedures are used to process these data. Finally, utilizing liquid continuity equation the functional dependency of permeability with respect to saturation is calculated. Some permeability results appear to be reasonable when compared with actual wood behavior during drying. Measurement procedures prove to yield accurate results for moisture content and saturation levels in wood with less than 5% relative error in average saturation level of .75. However, due to natural inhomogeneities in wood cellular structure, the final calculated results for unsaturated permeability show high levels of uncertainty (up to 112% relative error). Close

• 160. [Article] Hydrogeology of Pumice-Hosted Fens in the Winema-Fremont National Forest, Oregon, USA

  Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim ...

  Citation × Citation Citation Abstract Copy Title: Hydrogeology of Pumice-Hosted Fens in the Winema-Fremont National Forest, Oregon, USA Author: Cummings, Michael L., Weatherford, Jonathan Michael, Mowbray, Leslie A Year: 2014 Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim study area, erosion by ephemeral streams shortly after the eruption disrupted the lateral continuity of the 270 to 300 cm-thick pumice deposit. Co-evolution of the surface- and ground-water systems in a low-relief, low-slope landscape allowed diffuse groundwater discharge from the banks of the evolving stream system. Accumulation of organic material from groundwater dependent ecosystems at these sites of discharge allowed peat deposits to form on gently sloping erosion surfaces cut into the pumice deposit. Following early stream incision, fine-grained, silt-rich deposits accumulated in valleys and contributed permeability barriers to the lateral migration of water in the pumice aquifer. Fens discharge from the pumice aquifer through gently sloping surfaces patterned after the slope of the erosion surface cut into the pumice deposit and overlain by approximately 1 m of peat on the sloping surface and alluvium or iron-cemented pumice overlain by alluvium at the toe of the slope. The predominant source of groundwater is snowmelt which infiltrates the pumice deposit during the freshet. However, shallow groundwater flow also takes place along permeable pathways in bedrock units. Locally, low volume discharge takes place along faults. The snowmelt-dependent hydrologic system that supports the fens of the Walker Rim study area occurs at elevations primarily above 1585 m. Title: Hydrogeology of Pumice-Hosted Fens in the Winema-Fremont National Forest, Oregon, USA Author: Cummings, Michael L., Weatherford, Jonathan Michael, Mowbray, Leslie A Year: 2014 Subaerial fallout from the Holocene eruption of Mount Mazama in the Oregon Cascade Range was deposited upon relatively low permeability volcanic and volcaniclastic bedrock and regolith. In the Walker Rim study area, erosion by ephemeral streams shortly after the eruption disrupted the lateral continuity of the 270 to 300 cm-thick pumice deposit. Co-evolution of the surface- and ground-water systems in a low-relief, low-slope landscape allowed diffuse groundwater discharge from the banks of the evolving stream system. Accumulation of organic material from groundwater dependent ecosystems at these sites of discharge allowed peat deposits to form on gently sloping erosion surfaces cut into the pumice deposit. Following early stream incision, fine-grained, silt-rich deposits accumulated in valleys and contributed permeability barriers to the lateral migration of water in the pumice aquifer. Fens discharge from the pumice aquifer through gently sloping surfaces patterned after the slope of the erosion surface cut into the pumice deposit and overlain by approximately 1 m of peat on the sloping surface and alluvium or iron-cemented pumice overlain by alluvium at the toe of the slope. The predominant source of groundwater is snowmelt which infiltrates the pumice deposit during the freshet. However, shallow groundwater flow also takes place along permeable pathways in bedrock units. Locally, low volume discharge takes place along faults. The snowmelt-dependent hydrologic system that supports the fens of the Walker Rim study area occurs at elevations primarily above 1585 m. Close