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• 311. [Article] A Beer Party and Watermelon: The Archaeology of Community and Resistance at CCC Camp Zigzag, Company 928, Zigzag, Oregon, 1933-1942

  In March 1933, the administration of United States President Franklin D. Roosevelt initiated a national relief program aimed at alleviating the disastrous effects ofthe Great Depression. The Civilian Conservation ...

  Citation × Citation Citation Abstract Copy Title: A Beer Party and Watermelon: The Archaeology of Community and Resistance at CCC Camp Zigzag, Company 928, Zigzag, Oregon, 1933-1942 Author: Tuck, Janna Beth Year: 2010 In March 1933, the administration of United States President Franklin D. Roosevelt initiated a national relief program aimed at alleviating the disastrous effects ofthe Great Depression. The Civilian Conservation Corp (CCC) began as one of these programs designed to employ young men from all over the country and put them "back to work". The CCC provided these young men with training, a monthly stipend, and basic supplies such as food, clothing, and accommodations. After 1942, CCC camps were closed and many of these sites were abandoned or destroyed, leaving little historical documentation as to the experiences ofthe people involved. This project revolves around the archaeological investigations and data recovery of a CCC camp that was in operation from 1933-1942 in Zigzag, Oregon. This research analyzes the remains of the camp in order to gain further knowledge about this important period in American history, and more specifically, Oregon history. In assessing the material culture left behind, combined with the historical documents and oral history interviews, the goal of this project was to expand the historical and archaeological narrative of the CCC experience. More specifically, the aim of this research was to reveal the unwritten record of CCC camp life in a pivotal period of American history. The results of the historical archaeological research indicates that Camp Zigzag represents a community that participated in resistance related activities, such as drinking alcohol on camp property, but one that also adhered to the regulations of camp policy. Military-style order and training permeated even the surrounding architectural environment. The rituals of daily life in the structured order of the camp appear to have developed and formulated a strong sense of cohesion among the men. However, resistance-related items, such as alcohol bottles, suggest that Camp Zigzag enrollees resisted the authoritarian dynamic of the camp. Social drinking would have provided the men with a sense of solidarity and commonality that would have been maintained beyond the ideals of camp uniformity. This communal familiarity may have influenced the men's behaviour in daily camp routines, rituals, and work. Overall, the archaeological evidence depicts the Camp Zigzag community as united through the bonds of formality and in its resistance to it. Camp Zigzag offered a unique and unusually expansive window into not only the history of Oregon State, but into the history of our nation as a whole. The camp's archaeological assemblage remains as an important learning tool and its value far exceeds the humble nature of its material contents. It is a collection of untold stories representing the lives of young men and their families at a tumultuous turning point in American history. Title: A Beer Party and Watermelon: The Archaeology of Community and Resistance at CCC Camp Zigzag, Company 928, Zigzag, Oregon, 1933-1942 Author: Tuck, Janna Beth Year: 2010 In March 1933, the administration of United States President Franklin D. Roosevelt initiated a national relief program aimed at alleviating the disastrous effects ofthe Great Depression. The Civilian Conservation Corp (CCC) began as one of these programs designed to employ young men from all over the country and put them "back to work". The CCC provided these young men with training, a monthly stipend, and basic supplies such as food, clothing, and accommodations. After 1942, CCC camps were closed and many of these sites were abandoned or destroyed, leaving little historical documentation as to the experiences ofthe people involved. This project revolves around the archaeological investigations and data recovery of a CCC camp that was in operation from 1933-1942 in Zigzag, Oregon. This research analyzes the remains of the camp in order to gain further knowledge about this important period in American history, and more specifically, Oregon history. In assessing the material culture left behind, combined with the historical documents and oral history interviews, the goal of this project was to expand the historical and archaeological narrative of the CCC experience. More specifically, the aim of this research was to reveal the unwritten record of CCC camp life in a pivotal period of American history. The results of the historical archaeological research indicates that Camp Zigzag represents a community that participated in resistance related activities, such as drinking alcohol on camp property, but one that also adhered to the regulations of camp policy. Military-style order and training permeated even the surrounding architectural environment. The rituals of daily life in the structured order of the camp appear to have developed and formulated a strong sense of cohesion among the men. However, resistance-related items, such as alcohol bottles, suggest that Camp Zigzag enrollees resisted the authoritarian dynamic of the camp. Social drinking would have provided the men with a sense of solidarity and commonality that would have been maintained beyond the ideals of camp uniformity. This communal familiarity may have influenced the men's behaviour in daily camp routines, rituals, and work. Overall, the archaeological evidence depicts the Camp Zigzag community as united through the bonds of formality and in its resistance to it. Camp Zigzag offered a unique and unusually expansive window into not only the history of Oregon State, but into the history of our nation as a whole. The camp's archaeological assemblage remains as an important learning tool and its value far exceeds the humble nature of its material contents. It is a collection of untold stories representing the lives of young men and their families at a tumultuous turning point in American history. Close

• 312. [Article] Assessing the Impact of Restrictiveness and Placement Type on Transition-Related Outcomes for Youth With and Without Disabilities Aging Out of Foster Care

  Nearly 23,000 youth age out of the foster care system between the ages of 18 and 21 each year in a transition fraught with challenges and barriers. These young people often lack developmentally appropriate ...

  Citation × Citation Citation Abstract Copy Title: Assessing the Impact of Restrictiveness and Placement Type on Transition-Related Outcomes for Youth With and Without Disabilities Aging Out of Foster Care Author: Schmidt, Jessica Danielle Year: 2015 Nearly 23,000 youth age out of the foster care system between the ages of 18 and 21 each year in a transition fraught with challenges and barriers. These young people often lack developmentally appropriate experiences and exposure to necessary knowledge, role modeling, skill building, and long-term social support to promote positive transitions to adulthood while in foster care. As a result, young people who exit care face an array of poor adult outcomes. Nearly 60% of transition-aged foster youth experience a disability, and as such, face compounded challenges exiting foster care. While the examination of young adult outcomes for youth with disabilities has been largely missing from the literature, available research documents that young adults with disabilities who had exited foster care were significantly behind their peers without disabilities in several key areas. Literature examining the experiences of transition-aged youth with disabilities in the general population also highlights gaps in young adult outcomes for young people with disabilities compared to their peers. Compounding the issue for youth in foster care, those who experience disabilities often reside in restrictive placement settings such as developmental disability (DD) certified homes, group homes, or residential treatment centers. Though limited, there is some evidence to suggest that these types of placements negatively impact young adult outcomes for those aging out of foster care. The rules and regulations in place to promote safety in these types of placements could further restrict youth from engaging in meaningful transition preparation engagement while in foster care. Therefore, youth with disabilities, whose needs necessitate a higher level of support towards transition preparation engagement, may actually receive fewer opportunities than their peers in non-relative foster care and kinship care as they prepare to exit care into adulthood. The work in this dissertation provides knowledge to address gaps in the literature around transition preparation engagement during foster care for youth with disabilities, youth residing in restrictive foster care placements, and youth who report high levels of perceived restrictiveness as they prepare to enter into adulthood. This dissertation is a secondary analysis of transition preparation engagement data collected at baseline for 294 transition-aged youth in foster care who participated in an evaluation of an intervention to promote self-determination and enhance young adult outcomes, called My Life. Transition preparation engagement in this study was represented by eight domains: youth perceptions of preparedness for adult life, post-secondary education preparation engagement, career preparation engagement, employment, daily life preparation engagement, Independent Living Program (ILP) participation, transition planning engagement, and self-determination. Transition preparation engagement domains were examined using hierarchical multiple regression analysis to explore differences by disability status, placement setting, and youth self-report of perceptions of restrictiveness. In alignment with the literature, 58.8% of youth in this sample experienced a disability. Additional key demographics, including age, gender, and race, and foster care experiences, including length of time in care and placement instability, were entered into the regression models as covariates. Results indicated significantly less transition preparation engagement for 1) youth with disabilities compared to youth without disabilities, 2) youth residing in restrictive placements compared to youth in non-relative foster care and kinship care, and 3) youth who reported higher levels of perceived restrictiveness compared to youth who reported lower levels of perceived restrictiveness. Program, policy, and research recommendations are discussed that highlight the need to promote transition preparation engagement for this particularly vulnerable group of young people in foster care who experience disabilities, are residing in restrictive placement settings and who report high levels of perceived restrictiveness. Title: Assessing the Impact of Restrictiveness and Placement Type on Transition-Related Outcomes for Youth With and Without Disabilities Aging Out of Foster Care Author: Schmidt, Jessica Danielle Year: 2015 Nearly 23,000 youth age out of the foster care system between the ages of 18 and 21 each year in a transition fraught with challenges and barriers. These young people often lack developmentally appropriate experiences and exposure to necessary knowledge, role modeling, skill building, and long-term social support to promote positive transitions to adulthood while in foster care. As a result, young people who exit care face an array of poor adult outcomes. Nearly 60% of transition-aged foster youth experience a disability, and as such, face compounded challenges exiting foster care. While the examination of young adult outcomes for youth with disabilities has been largely missing from the literature, available research documents that young adults with disabilities who had exited foster care were significantly behind their peers without disabilities in several key areas. Literature examining the experiences of transition-aged youth with disabilities in the general population also highlights gaps in young adult outcomes for young people with disabilities compared to their peers. Compounding the issue for youth in foster care, those who experience disabilities often reside in restrictive placement settings such as developmental disability (DD) certified homes, group homes, or residential treatment centers. Though limited, there is some evidence to suggest that these types of placements negatively impact young adult outcomes for those aging out of foster care. The rules and regulations in place to promote safety in these types of placements could further restrict youth from engaging in meaningful transition preparation engagement while in foster care. Therefore, youth with disabilities, whose needs necessitate a higher level of support towards transition preparation engagement, may actually receive fewer opportunities than their peers in non-relative foster care and kinship care as they prepare to exit care into adulthood. The work in this dissertation provides knowledge to address gaps in the literature around transition preparation engagement during foster care for youth with disabilities, youth residing in restrictive foster care placements, and youth who report high levels of perceived restrictiveness as they prepare to enter into adulthood. This dissertation is a secondary analysis of transition preparation engagement data collected at baseline for 294 transition-aged youth in foster care who participated in an evaluation of an intervention to promote self-determination and enhance young adult outcomes, called My Life. Transition preparation engagement in this study was represented by eight domains: youth perceptions of preparedness for adult life, post-secondary education preparation engagement, career preparation engagement, employment, daily life preparation engagement, Independent Living Program (ILP) participation, transition planning engagement, and self-determination. Transition preparation engagement domains were examined using hierarchical multiple regression analysis to explore differences by disability status, placement setting, and youth self-report of perceptions of restrictiveness. In alignment with the literature, 58.8% of youth in this sample experienced a disability. Additional key demographics, including age, gender, and race, and foster care experiences, including length of time in care and placement instability, were entered into the regression models as covariates. Results indicated significantly less transition preparation engagement for 1) youth with disabilities compared to youth without disabilities, 2) youth residing in restrictive placements compared to youth in non-relative foster care and kinship care, and 3) youth who reported higher levels of perceived restrictiveness compared to youth who reported lower levels of perceived restrictiveness. Program, policy, and research recommendations are discussed that highlight the need to promote transition preparation engagement for this particularly vulnerable group of young people in foster care who experience disabilities, are residing in restrictive placement settings and who report high levels of perceived restrictiveness. Close

• 313. [Article] Effects of Daily Social Support on Tension-Reduction Drinking

  Researchers have argued that in times of need having supportive, caring people available can make all the difference between achieving optimum health and well-being or suffering from mental or physical ...

  Citation × Citation Citation Abstract Copy Title: Effects of Daily Social Support on Tension-Reduction Drinking Author: Brannan, Deborah L. Year: 2011 Researchers have argued that in times of need having supportive, caring people available can make all the difference between achieving optimum health and well-being or suffering from mental or physical illness (Cobb, 1976; Sarason & Sarason, 1985; Thoits, 1986). The direct-effect model of support postulates that having the knowledge of available relationship resources (i.e., perceived support) and receiving benefits from those relationships (i.e., received support) both have beneficial effects on health behaviors and well-being (Cohen & Wills, 1985). According to the stress-buffering model, when stressors are encountered, the certainty of having available resources, as well as having tangible support resources, is hypothesized to lessen the negative effects of stressors (Cohen, et al., 2000; Cohen &Wills, 1985, Cutrona, 1986; Thoits, 1986). Most of the research that has examined social support effects on drinking-related outcomes has focused on the association between support and alcohol problems, particularly among high risk populations (those who are alcohol dependent, alcohol abusers, or adolescents). Yet, it could be argued that when examining drinking levels, not all consumption is harmful. Of particular concern is drinking that is motivated to reduce negative or stressful experiences. Individuals who use drinking as a method of avoidant coping, or reducing tension drink significantly more alcohol and be at a greater risk for developing later drinking problems (Cooper, Russell, & George, 1988). Research employing daily process methodology has been able to resolve documented methodological inconsistencies (e.g., Greeley & Oei, 1999) by examining the within-person processes between negative experiences and alcohol consumption (Tennen & Affleck, 1996; Tennen, Affleck, Armeli, & Carney, 2000; Mohr et al., 2008). Similarly, these methodologies have been useful to social support researchers in helping to understand social support as a within-person process rather than just an interpersonal event between two individuals. This research was part of a larger study about the influence of alcohol use on daily emotion regulation among 47 moderate-to-heavy drinking adults in the local metropolitan area. Participants carried a personal data assistant (handheld interviewer) for 30 days, responding to surveys three times each day (late afternoon, evening). Each survey probed supportive and negative interpersonal exchanges and drinking behaviors. Prior to the daily diary portion of the study, participants completed the Interpersonal Support Evaluation List, a measure of perceived social support. For purposes of analyses, I examined the extent to which exchanges occurring in an earlier interview predicted subsequent solitary drinking at home using data from 2 of the three interviews (predicting evening and late evening drinking only). My analyses revealed that daily socially supportive exchanges had a significant direct effect on subsequent drinking at home alone. Interestingly, the daily supportive exchanges did not buffer the negative exchanges-later drinking relationship. However, my findings revealed that negative exchanges also resulted in a reduction in subsequent consumption, which contrasts previous studies that used similar methodologies but with heavier drinkers (e.g., Mohr et al., 2001). Further, perceived support was not related to solitary consumption. The results of this study indicate that in healthy adults, positively appraised received support directly reduces solitary consumption. This is an important finding given that received support is difficult to document. At the same time, my results showed that among these types of drinkers, negative exchanges may have a stronger direct effect than positive exchanges on solitary consumption. In non-clinical samples, such as this the relationship between social support and drinking is not straightforward. Thus, using a sophisticated methodology (i.e., daily process methods), this study was able to examine the relationship of drinking and social support on a daily basis; thus, further bridging the gap between social support and the drinking literature. Title: Effects of Daily Social Support on Tension-Reduction Drinking Author: Brannan, Deborah L. Year: 2011 Researchers have argued that in times of need having supportive, caring people available can make all the difference between achieving optimum health and well-being or suffering from mental or physical illness (Cobb, 1976; Sarason & Sarason, 1985; Thoits, 1986). The direct-effect model of support postulates that having the knowledge of available relationship resources (i.e., perceived support) and receiving benefits from those relationships (i.e., received support) both have beneficial effects on health behaviors and well-being (Cohen & Wills, 1985). According to the stress-buffering model, when stressors are encountered, the certainty of having available resources, as well as having tangible support resources, is hypothesized to lessen the negative effects of stressors (Cohen, et al., 2000; Cohen &Wills, 1985, Cutrona, 1986; Thoits, 1986). Most of the research that has examined social support effects on drinking-related outcomes has focused on the association between support and alcohol problems, particularly among high risk populations (those who are alcohol dependent, alcohol abusers, or adolescents). Yet, it could be argued that when examining drinking levels, not all consumption is harmful. Of particular concern is drinking that is motivated to reduce negative or stressful experiences. Individuals who use drinking as a method of avoidant coping, or reducing tension drink significantly more alcohol and be at a greater risk for developing later drinking problems (Cooper, Russell, & George, 1988). Research employing daily process methodology has been able to resolve documented methodological inconsistencies (e.g., Greeley & Oei, 1999) by examining the within-person processes between negative experiences and alcohol consumption (Tennen & Affleck, 1996; Tennen, Affleck, Armeli, & Carney, 2000; Mohr et al., 2008). Similarly, these methodologies have been useful to social support researchers in helping to understand social support as a within-person process rather than just an interpersonal event between two individuals. This research was part of a larger study about the influence of alcohol use on daily emotion regulation among 47 moderate-to-heavy drinking adults in the local metropolitan area. Participants carried a personal data assistant (handheld interviewer) for 30 days, responding to surveys three times each day (late afternoon, evening). Each survey probed supportive and negative interpersonal exchanges and drinking behaviors. Prior to the daily diary portion of the study, participants completed the Interpersonal Support Evaluation List, a measure of perceived social support. For purposes of analyses, I examined the extent to which exchanges occurring in an earlier interview predicted subsequent solitary drinking at home using data from 2 of the three interviews (predicting evening and late evening drinking only). My analyses revealed that daily socially supportive exchanges had a significant direct effect on subsequent drinking at home alone. Interestingly, the daily supportive exchanges did not buffer the negative exchanges-later drinking relationship. However, my findings revealed that negative exchanges also resulted in a reduction in subsequent consumption, which contrasts previous studies that used similar methodologies but with heavier drinkers (e.g., Mohr et al., 2001). Further, perceived support was not related to solitary consumption. The results of this study indicate that in healthy adults, positively appraised received support directly reduces solitary consumption. This is an important finding given that received support is difficult to document. At the same time, my results showed that among these types of drinkers, negative exchanges may have a stronger direct effect than positive exchanges on solitary consumption. In non-clinical samples, such as this the relationship between social support and drinking is not straightforward. Thus, using a sophisticated methodology (i.e., daily process methods), this study was able to examine the relationship of drinking and social support on a daily basis; thus, further bridging the gap between social support and the drinking literature. Close

• 314. [Article] Mechanism of Calcium Release from Skeletal Muscle Sarcoplasmic Reticulum

  The sarcoplasmic reticulum (SR) is an intracellular membrane system dedicated to the active regulation of cytosolic calcium in muscle. The opening of Ca²⁺ channels in the SR results in a rapid increase ...

  Citation × Citation Citation Abstract Copy Title: Mechanism of Calcium Release from Skeletal Muscle Sarcoplasmic Reticulum Author: Buck, Edmond Year: 1993 The sarcoplasmic reticulum (SR) is an intracellular membrane system dedicated to the active regulation of cytosolic calcium in muscle. The opening of Ca²⁺ channels in the SR results in a rapid increase in the myoplasmic Ca²⁺ concentration and the initiation of contraction. Closure of these channels allows the SR to re-accumulate the released Ca²⁺ which results in muscle relaxation. While it is known that a muscle fiber is stimulated to contract by the depolarization of the sarcolemma, it is not understood how this signal is communicated to the SR. The focus of this dissertation is twofold. The first objective is to gain an understanding of the mechanism of Ca²⁺ release from the SR. To this end, three studies have been performed which indicate that Ca²⁺ release is mediated by an oxidation reaction. The second goal is to gain insight into the function of the Ca²⁺ release channel. This is addressed by a fourth study which characterizes the effect of the plant alkaloid, ryanodine on channel operation. The anthraquinones mitoxantrone , doxorubicin, daunorubicin, and rubidazone are shown to be potent stimulators of Ca²⁺ release from SR vesicles. Anthraquinoneinduced Ca²⁺ release is shown to be via a specific interaction with the Ca²⁺ release system of the SR. In addition, a strong interaction between anthraquinone and caffeine binding sites on the Ca²⁺ release channel is observed when monitoring Ca²⁺ fluxes across the SR. It is shown that Ca²⁺ release stimulated by anthraquinones is inhibited by preincubating the quinone with dithionite, a strong reducing agent. Spectrophotometric measurements show that the dithionite treated quinone is in a reduced state. Previous work in this lab has shown that the photooxidizing xanthene dye rose bengal stimulates rapid Ca²⁺ release from skeletal muscle SR vesicles. In this thesis, it is shown that following fusion of vesicles to a bilayer lipid membrane (BLM), Ca²⁺ channel activity is stimulated by nanomolar concentrations of rose bengal in the presence of a broad-spectrum light source. This stimulation is shown to be independent of the Ca²⁺ concentration but is inhibited by μM ruthenium red. The photooxidation of rose bengal is shown to not affect either the K+ or Cl- channels which are present in the SR. Exposure of the Ca²⁺ release channel to 500 nM rose bengal in the presence of light is shown to reverse the modification to the channel induced by μM ryanodine. This apparent displacement of bound ryanodine by nanomolar concentrations of rose bengal is directly observed upon measurement of [³H]ryanodine binding to TSR vesicles. Evidence is presented which suggests that Ca²⁺ release is mediated by singlet oxygen. Micromolar concentrations of the porphyrin meso-Tetra(4-N-methylpyridyl)porphine tetraiodide (TMPyP) is shown to induce the rapid release of Ca²⁺ from skeletal muscle SR vesicles. Porphyrin-induced Ca²⁺ release is stimulated by adenine nucleotides and μM Ca²⁺, and is inhibited by mM Mg²⁺ and μM ruthenium red. High-affinity [³H]ryanodine binding is also enhanced in the presence of the porphyrin. The presence of 1 mM Mg²⁺ in the assay medium sensitizes ryanodine binding to activation by ca²⁺. Porphyrin stimulated single channel activity is also sensitized to activation by Ca²⁺ in the presence of Mg²⁺. Reduction of the porphyrin by dithionite, a strong reducing agent, prior to exposure to the Ca²⁺ release channel inhibited the ability of TMPyP to stimulate Ca²⁺ release. These observations indicate that anthraquinones, rose bengal , and porphyrins induce a stimulation of the Ca²⁺ release protein from skeletal muscle SR by interacting with the ryanodine binding site. In addition, the mechanism of interaction for these compounds appears to be via an oxidation reaction. Nanomolar to micromolar concentrations of ryanodine are shown to alter the gating kinetics of the Ca²⁺ release channel from skeletal muscle SR fused with bilayer lipid membranes. In the presence of asymmetric CsCl, 5 to 40 nM concentrations of ryanodine are shown to activate the channel by increasing the open probability (P₀) without changing the conductance. Statistical analysis of gating kinetics reveal that the open and closed dwell times exhibit bi-exponential distributions that are significantly modified by nM ryanodine. The altered channel gating kinetics seen with low nM ryanodine is reversible and is shown to correlate with the binding kinetics of [³H]ryanodine with its highest affinity site under identical ionic conditions. Ryanodine concentrations between 20 and 50 nM are observed to induce occasional 1/2 conductance fluctuations while ryanodine concentrations greater than 50 nM stabilize the channel into a ½ conductance state which is not reversible. These results are shown to correlate with [³H]ryanodine binding to a second site having lower affinity than the first site. Ryanodine at concentrations greater than 70 μM from the 1/2 to a 1/4 conductance fluctuation , whereas ryanodine concentrations greater than 200 μM cause complete closure of the channel. The concentration of ryanodine required to stabilize either the 1/4 conductance transitions or channel closure do not directly correlate with the measured [³H]ryanodine equilibrium binding constants. However, these results can be explained by considering the association kinetics of ryanodine concentrations greater than 200 nM in the presence of 500 mM CsCl. These results indicate that ryanodine stabilizes four discrete states of the SR release channel and supports the existence of multiple interacting ryanodine binding sites on the channel protein. Title: Mechanism of Calcium Release from Skeletal Muscle Sarcoplasmic Reticulum Author: Buck, Edmond Year: 1993 The sarcoplasmic reticulum (SR) is an intracellular membrane system dedicated to the active regulation of cytosolic calcium in muscle. The opening of Ca²⁺ channels in the SR results in a rapid increase in the myoplasmic Ca²⁺ concentration and the initiation of contraction. Closure of these channels allows the SR to re-accumulate the released Ca²⁺ which results in muscle relaxation. While it is known that a muscle fiber is stimulated to contract by the depolarization of the sarcolemma, it is not understood how this signal is communicated to the SR. The focus of this dissertation is twofold. The first objective is to gain an understanding of the mechanism of Ca²⁺ release from the SR. To this end, three studies have been performed which indicate that Ca²⁺ release is mediated by an oxidation reaction. The second goal is to gain insight into the function of the Ca²⁺ release channel. This is addressed by a fourth study which characterizes the effect of the plant alkaloid, ryanodine on channel operation. The anthraquinones mitoxantrone , doxorubicin, daunorubicin, and rubidazone are shown to be potent stimulators of Ca²⁺ release from SR vesicles. Anthraquinoneinduced Ca²⁺ release is shown to be via a specific interaction with the Ca²⁺ release system of the SR. In addition, a strong interaction between anthraquinone and caffeine binding sites on the Ca²⁺ release channel is observed when monitoring Ca²⁺ fluxes across the SR. It is shown that Ca²⁺ release stimulated by anthraquinones is inhibited by preincubating the quinone with dithionite, a strong reducing agent. Spectrophotometric measurements show that the dithionite treated quinone is in a reduced state. Previous work in this lab has shown that the photooxidizing xanthene dye rose bengal stimulates rapid Ca²⁺ release from skeletal muscle SR vesicles. In this thesis, it is shown that following fusion of vesicles to a bilayer lipid membrane (BLM), Ca²⁺ channel activity is stimulated by nanomolar concentrations of rose bengal in the presence of a broad-spectrum light source. This stimulation is shown to be independent of the Ca²⁺ concentration but is inhibited by μM ruthenium red. The photooxidation of rose bengal is shown to not affect either the K+ or Cl- channels which are present in the SR. Exposure of the Ca²⁺ release channel to 500 nM rose bengal in the presence of light is shown to reverse the modification to the channel induced by μM ryanodine. This apparent displacement of bound ryanodine by nanomolar concentrations of rose bengal is directly observed upon measurement of [³H]ryanodine binding to TSR vesicles. Evidence is presented which suggests that Ca²⁺ release is mediated by singlet oxygen. Micromolar concentrations of the porphyrin meso-Tetra(4-N-methylpyridyl)porphine tetraiodide (TMPyP) is shown to induce the rapid release of Ca²⁺ from skeletal muscle SR vesicles. Porphyrin-induced Ca²⁺ release is stimulated by adenine nucleotides and μM Ca²⁺, and is inhibited by mM Mg²⁺ and μM ruthenium red. High-affinity [³H]ryanodine binding is also enhanced in the presence of the porphyrin. The presence of 1 mM Mg²⁺ in the assay medium sensitizes ryanodine binding to activation by ca²⁺. Porphyrin stimulated single channel activity is also sensitized to activation by Ca²⁺ in the presence of Mg²⁺. Reduction of the porphyrin by dithionite, a strong reducing agent, prior to exposure to the Ca²⁺ release channel inhibited the ability of TMPyP to stimulate Ca²⁺ release. These observations indicate that anthraquinones, rose bengal , and porphyrins induce a stimulation of the Ca²⁺ release protein from skeletal muscle SR by interacting with the ryanodine binding site. In addition, the mechanism of interaction for these compounds appears to be via an oxidation reaction. Nanomolar to micromolar concentrations of ryanodine are shown to alter the gating kinetics of the Ca²⁺ release channel from skeletal muscle SR fused with bilayer lipid membranes. In the presence of asymmetric CsCl, 5 to 40 nM concentrations of ryanodine are shown to activate the channel by increasing the open probability (P₀) without changing the conductance. Statistical analysis of gating kinetics reveal that the open and closed dwell times exhibit bi-exponential distributions that are significantly modified by nM ryanodine. The altered channel gating kinetics seen with low nM ryanodine is reversible and is shown to correlate with the binding kinetics of [³H]ryanodine with its highest affinity site under identical ionic conditions. Ryanodine concentrations between 20 and 50 nM are observed to induce occasional 1/2 conductance fluctuations while ryanodine concentrations greater than 50 nM stabilize the channel into a ½ conductance state which is not reversible. These results are shown to correlate with [³H]ryanodine binding to a second site having lower affinity than the first site. Ryanodine at concentrations greater than 70 μM from the 1/2 to a 1/4 conductance fluctuation , whereas ryanodine concentrations greater than 200 μM cause complete closure of the channel. The concentration of ryanodine required to stabilize either the 1/4 conductance transitions or channel closure do not directly correlate with the measured [³H]ryanodine equilibrium binding constants. However, these results can be explained by considering the association kinetics of ryanodine concentrations greater than 200 nM in the presence of 500 mM CsCl. These results indicate that ryanodine stabilizes four discrete states of the SR release channel and supports the existence of multiple interacting ryanodine binding sites on the channel protein. Close

• 315. [Article] Predicting Parturition in a Long-Gestating Species: Behavioral and Hormonal Indicators in the Asian Elephant (Elephas maximus)

  Captive populations of Asian elephants (Elephas maximus) in North America are not self-sustaining, and increasing reproductive success within captive populations is a high priority. The ability to accurately ...

  Citation × Citation Citation Abstract Copy Title: Predicting Parturition in a Long-Gestating Species: Behavioral and Hormonal Indicators in the Asian Elephant (Elephas maximus) Author: Velonis, Heather Kelly Year: 2017 Captive populations of Asian elephants (Elephas maximus) in North America are not self-sustaining, and increasing reproductive success within captive populations is a high priority. The ability to accurately predict parturition can have a direct impact on elephant welfare. Elephants in captivity often require significant preparation and management throughout the birthing process, and complications during labor and delivery can necessitate immediate intervention, including stillbirth, protracted labor, maternal aggression towards a newborn calf, and dystocia. Being able to predict when parturition will commence can ensure appropriate staff is available and adequate monitoring is performed. Routine endocrine sampling can be used to predict parturition in Asian elephants, with a drop in progesterone (P4) to baseline levels signaling parturition in 2-5 days. However, we determined this method is not without limitations, and it is not used in all institutions that house elephants. As changes in hormones regulate and alter behaviors, we investigated behavioral indicators as an additional management tool for predicting parturition, a time of drastic hormone changes. We conducted a study of five pregnancies in Asian elephants at the Oregon Zoo, U.S.A, and Taronga Zoo, Australia, between 2008 and 2012. In Chapter 2, I evaluated progesterone (P4) and cortisol levels across three time periods: Baseline; Pre, (the week preceding the drop in P4); and Post, (the period after the P4 drop). Levels of P4 were significantly lower, and levels of cortisol were significantly higher in the days just prior to parturition. I found considerable intra- and inter-individual variation in both endocrine profiles, which can make endocrine assessments difficult to interpret in real time. In Chapter 3, I investigated whether behaviors in the preparturition period could be predictive of impending parturition in the Asian elephant. ANOVA results indicated a significant difference in the amount of time that elephants spent walking backwards across three time periods (F(2) = 3.723, p = 0.033), with the behavior increasing as parturition approached. These results were supported by a non-parametric Kruskal- Wallis. Using a generalized linear mixed model (GLMM), I found that as P4 levels decrease, walking backwards behavior significantly increases. In Chapter 4, I evaluated investigative trunk behaviors, or “trunk checks”, directed towards the temporal gland near the ear, mammary glands, vulva and anus of the pregnant dam. Investigative behaviors included both self-directed behaviors and those sent from herd mates towards the pregnant dam. Self-directed behaviors are most likely associated with physical changes in the pregnant dam, such as using the trunk to pull on swollen teats. Other-directed behaviors may stem from chemo-sensory signaling or other types of communication between herd mates, such as detecting changes in progesterone or cortisol. I ran GLMM and found that four trunk-check behaviors varied significantly with P4 and/or cortisol profiles. These were: self-checks of mammary glands increased with decreasing P4 levels; herd-mate-checks of mammary glands increased with decreasing P4 levels; self-checks of vulva increased with decreasing P4 levels and increasing cortisol levels; herd-mate-checks of anus increased with increasing cortisol levels. In Chapter 5, I evaluated activity budget behaviors in the pregnant elephants. Generalized comparisons were made to published activity budgets of typical captive Asian elephants. I report that activity budgets are within the range of normal activity, though I note a high level of inter-individual variation. In addition, I compared two sampling techniques, including one-zero and instantaneous sampling, that were used for activity budget data collection. I discuss the different results obtained by each sampling technique. These results are a very promising indication that behaviors, including walking backwards and multiple trunk-check behaviors, are changing over time or with parturition-related hormone profiles. We recommend that keepers, veterinary staff, and other observers that are familiar with the regular behavioral repertoire of a pregnant female should pay close attention to these highlighted behaviors. Keeping track of these behaviors, especially in conjunction with P4 and cortisol tracking, can help staff refine existing windows of expected parturition. Title: Predicting Parturition in a Long-Gestating Species: Behavioral and Hormonal Indicators in the Asian Elephant (Elephas maximus) Author: Velonis, Heather Kelly Year: 2017 Captive populations of Asian elephants (Elephas maximus) in North America are not self-sustaining, and increasing reproductive success within captive populations is a high priority. The ability to accurately predict parturition can have a direct impact on elephant welfare. Elephants in captivity often require significant preparation and management throughout the birthing process, and complications during labor and delivery can necessitate immediate intervention, including stillbirth, protracted labor, maternal aggression towards a newborn calf, and dystocia. Being able to predict when parturition will commence can ensure appropriate staff is available and adequate monitoring is performed. Routine endocrine sampling can be used to predict parturition in Asian elephants, with a drop in progesterone (P4) to baseline levels signaling parturition in 2-5 days. However, we determined this method is not without limitations, and it is not used in all institutions that house elephants. As changes in hormones regulate and alter behaviors, we investigated behavioral indicators as an additional management tool for predicting parturition, a time of drastic hormone changes. We conducted a study of five pregnancies in Asian elephants at the Oregon Zoo, U.S.A, and Taronga Zoo, Australia, between 2008 and 2012. In Chapter 2, I evaluated progesterone (P4) and cortisol levels across three time periods: Baseline; Pre, (the week preceding the drop in P4); and Post, (the period after the P4 drop). Levels of P4 were significantly lower, and levels of cortisol were significantly higher in the days just prior to parturition. I found considerable intra- and inter-individual variation in both endocrine profiles, which can make endocrine assessments difficult to interpret in real time. In Chapter 3, I investigated whether behaviors in the preparturition period could be predictive of impending parturition in the Asian elephant. ANOVA results indicated a significant difference in the amount of time that elephants spent walking backwards across three time periods (F(2) = 3.723, p = 0.033), with the behavior increasing as parturition approached. These results were supported by a non-parametric Kruskal- Wallis. Using a generalized linear mixed model (GLMM), I found that as P4 levels decrease, walking backwards behavior significantly increases. In Chapter 4, I evaluated investigative trunk behaviors, or “trunk checks”, directed towards the temporal gland near the ear, mammary glands, vulva and anus of the pregnant dam. Investigative behaviors included both self-directed behaviors and those sent from herd mates towards the pregnant dam. Self-directed behaviors are most likely associated with physical changes in the pregnant dam, such as using the trunk to pull on swollen teats. Other-directed behaviors may stem from chemo-sensory signaling or other types of communication between herd mates, such as detecting changes in progesterone or cortisol. I ran GLMM and found that four trunk-check behaviors varied significantly with P4 and/or cortisol profiles. These were: self-checks of mammary glands increased with decreasing P4 levels; herd-mate-checks of mammary glands increased with decreasing P4 levels; self-checks of vulva increased with decreasing P4 levels and increasing cortisol levels; herd-mate-checks of anus increased with increasing cortisol levels. In Chapter 5, I evaluated activity budget behaviors in the pregnant elephants. Generalized comparisons were made to published activity budgets of typical captive Asian elephants. I report that activity budgets are within the range of normal activity, though I note a high level of inter-individual variation. In addition, I compared two sampling techniques, including one-zero and instantaneous sampling, that were used for activity budget data collection. I discuss the different results obtained by each sampling technique. These results are a very promising indication that behaviors, including walking backwards and multiple trunk-check behaviors, are changing over time or with parturition-related hormone profiles. We recommend that keepers, veterinary staff, and other observers that are familiar with the regular behavioral repertoire of a pregnant female should pay close attention to these highlighted behaviors. Keeping track of these behaviors, especially in conjunction with P4 and cortisol tracking, can help staff refine existing windows of expected parturition. Close

• 316. [Article] Beyond the Angle of Repose: A Review and Synthesis of Landslide Processes in Response to Rapid Uplift, Eel River, Northern Eel River, Northern California

  In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope ...

  Citation × Citation Citation Abstract Copy Title: Beyond the Angle of Repose: A Review and Synthesis of Landslide Processes in Response to Rapid Uplift, Eel River, Northern Eel River, Northern California Author: Roering, Joshua J., Mackey, Benjamin H., Handwerger, Alexander L., Booth, Adam M., Schmidt, David A., Bennett, Georgina L., Cerovski-Darriau, Corina Year: 2015 In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope angles approach a limiting value. For decades, the threshold slope model has been invoked to account for landslide-driven increases in sediment flux that limit topographic relief, but the manner by which slope failures organize themselves spatially and temporally in order for erosion to keep pace with rock uplift has not been well documented. Here, we review past work and present new findings from remote sensing, cosmogenic adionuclides, suspended sediment records, and airborne lidar data, to decipher patterns of landslide activity and geomorphic processes related to rapid uplift along the northward-migrating Mendocino Triple Junction in Northern California. From historical air photos and airborne lidar, we estimated the velocity and sediment flux associated with active, slow-moving landslides (or earthflows) in the mélange- and argillite-dominated Eel River watershed using the downslope displacement of surface markers such as trees and shrubs. Although active landslides that directly convey sediment into the channel network account for only 7% of the landscape surface, their sediment flux amounts to more than 50% of the suspended load recorded at downstream sediment gauging stations. These active slides tend to exhibit seasonal variations in velocity as satellite-based interferometry has demonstrated that rapid acceleration commences within 1 to 2 months of the onset of autumn rainfall events before slower deceleration ensues in the spring and summer months. Curiously, this seasonal velocity pattern does not appear to vary with landslide size, suggesting that complex hydrologic-mechanical feedbacks (rather than 1-D pore pressure diffusion) may govern slide dynamics. A new analysis of 14 years of discharge and sediment concentration data for the Eel River indicates that the characteristic mid-winter timing of earthflow acceleration corresponds with increased suspended concentration values, suggesting that the seasonal onset of landslide motion each year may be reflected in the export of sediments to the continental margin. The vast majority of active slides exhibit gullied surfaces and the gully networks, which are also seasonally active, may facilitate sediment export although the proportion of material produced by this pathway is poorly known. Along Kekawaka Creek, a prominent tributary to the Eel River, new analyses of catchment-averaged erosion rates derived from cosmogenic radionuclides reveal rapid erosion (0.76 mm/yr) below a prominent knickpoint and slower erosion (0.29 mm/yr) upstream. Such knickpoints are frequently observed in Eel tributaries and are usually comprised of massive (>10m) interlocking resistant boulders that likely persist in the landscape for long time periods (>105yr). Upstream of these knickpoints, active landslides tend to be less frequent and average slope angles are slightly gentler than in downstream areas, which indicates that landslide density and average slope angle appear to increase with erosion rate. Lastly, we synthesize evidence for the role of large, catastrophic landslides in regulating sediment flux and landscape form. The emergence of resistant blocks within the mélange bedrock has promoted large catastrophic slides that have dammed the Eel River and perhaps generated outburst events in the past. The frequency and impact of these landslide dams likely depend on the spatial and size distributions of resistant blocks relative to the width and drainage area of adjacent valley networks. Overall, our findings demonstrate that landslides within the Eel River catchment do not occur randomly, but instead exhibit spatial and temporal patterns related to baselevel lowering, climate forcing, and lithologic variations. Combined with recent landscape evolution models that incorporate landslides, these results provide predictive capability for estimating erosion rates and managing hazards in mountainous regions. Title: Beyond the Angle of Repose: A Review and Synthesis of Landslide Processes in Response to Rapid Uplift, Eel River, Northern Eel River, Northern California Author: Roering, Joshua J., Mackey, Benjamin H., Handwerger, Alexander L., Booth, Adam M., Schmidt, David A., Bennett, Georgina L., Cerovski-Darriau, Corina Year: 2015 In mountainous settings, increases in rock uplift are often followed by a commensurate uptick in denudation as rivers incise and steepen hillslopes, making them increasingly prone to landsliding as slope angles approach a limiting value. For decades, the threshold slope model has been invoked to account for landslide-driven increases in sediment flux that limit topographic relief, but the manner by which slope failures organize themselves spatially and temporally in order for erosion to keep pace with rock uplift has not been well documented. Here, we review past work and present new findings from remote sensing, cosmogenic adionuclides, suspended sediment records, and airborne lidar data, to decipher patterns of landslide activity and geomorphic processes related to rapid uplift along the northward-migrating Mendocino Triple Junction in Northern California. From historical air photos and airborne lidar, we estimated the velocity and sediment flux associated with active, slow-moving landslides (or earthflows) in the mélange- and argillite-dominated Eel River watershed using the downslope displacement of surface markers such as trees and shrubs. Although active landslides that directly convey sediment into the channel network account for only 7% of the landscape surface, their sediment flux amounts to more than 50% of the suspended load recorded at downstream sediment gauging stations. These active slides tend to exhibit seasonal variations in velocity as satellite-based interferometry has demonstrated that rapid acceleration commences within 1 to 2 months of the onset of autumn rainfall events before slower deceleration ensues in the spring and summer months. Curiously, this seasonal velocity pattern does not appear to vary with landslide size, suggesting that complex hydrologic-mechanical feedbacks (rather than 1-D pore pressure diffusion) may govern slide dynamics. A new analysis of 14 years of discharge and sediment concentration data for the Eel River indicates that the characteristic mid-winter timing of earthflow acceleration corresponds with increased suspended concentration values, suggesting that the seasonal onset of landslide motion each year may be reflected in the export of sediments to the continental margin. The vast majority of active slides exhibit gullied surfaces and the gully networks, which are also seasonally active, may facilitate sediment export although the proportion of material produced by this pathway is poorly known. Along Kekawaka Creek, a prominent tributary to the Eel River, new analyses of catchment-averaged erosion rates derived from cosmogenic radionuclides reveal rapid erosion (0.76 mm/yr) below a prominent knickpoint and slower erosion (0.29 mm/yr) upstream. Such knickpoints are frequently observed in Eel tributaries and are usually comprised of massive (>10m) interlocking resistant boulders that likely persist in the landscape for long time periods (>105yr). Upstream of these knickpoints, active landslides tend to be less frequent and average slope angles are slightly gentler than in downstream areas, which indicates that landslide density and average slope angle appear to increase with erosion rate. Lastly, we synthesize evidence for the role of large, catastrophic landslides in regulating sediment flux and landscape form. The emergence of resistant blocks within the mélange bedrock has promoted large catastrophic slides that have dammed the Eel River and perhaps generated outburst events in the past. The frequency and impact of these landslide dams likely depend on the spatial and size distributions of resistant blocks relative to the width and drainage area of adjacent valley networks. Overall, our findings demonstrate that landslides within the Eel River catchment do not occur randomly, but instead exhibit spatial and temporal patterns related to baselevel lowering, climate forcing, and lithologic variations. Combined with recent landscape evolution models that incorporate landslides, these results provide predictive capability for estimating erosion rates and managing hazards in mountainous regions. Close

• 317. [Article] Report on Nutria Management and Research in the Pacific Northwest

  The nutria (Myocastor coypus) is a large semi-aquatic mammal native to South America that has been introduced to numerous countries around the world, primarily for fur farming. Nutria were introduced in ...

  Citation × Citation Citation Abstract Copy Title: Report on Nutria Management and Research in the Pacific Northwest Author: Sheffels, Trevor Robert, Sytsma, Mark Year: 2007 The nutria (Myocastor coypus) is a large semi-aquatic mammal native to South America that has been introduced to numerous countries around the world, primarily for fur farming. Nutria were introduced in Oregon and Washington in the 1930s, and feral populations were documented in 1943. Populations are known to be expanding in both Oregon and Washington, and regional nutria damage and nuisance complaints have increased in recent years. Most of the extensive damage caused by nutria is a direct result of feeding and burrowing, but nutria are also capable of transporting parasites and pathogens transmittable to humans, livestock, and pets. Although several past regional and local nutria research and management projects have been identified, there is a shortage of nutria information from the Pacific Northwest considering that the species has been present in the region for approximately seventy years. The Center for Lakes and Reservoirs (CLR) at Portland State University (PSU), in partnership with several local, state, and federal agencies, has taken the lead in addressing the regional nutria problem. Activities completed to date include a regional nutria management workshop, the ongoing development of a regional nutria distribution/density map, and a research project to analyze the impact of nutria herbivory on regional riparian wetland habitat restoration projects. In addition, the CLR at PSU is participating in the development of the national Aquatic Nuisance Species Task Force nutria management plan. This initial assessment of the current nutria situation in the Pacific Northwest conducted by the CLR at PSU has revealed that regional nutria problems are more extensive than previously realized. Nutria sightings have now been confirmed from the Canadian border to near the southern border of Oregon, confirming a larger range than was previously known. It was also found that the main nutria issues in the Pacific Northwest differ from the main nutria issues in Louisiana and Maryland. For example, the most significant category of regional nutria damage appears to be the destruction of water control structures and associated erosion caused by nutria burrowing, as opposed to nutria herbivory damage in Louisiana and Maryland. Another unique situation in the Pacific Northwest is the high density of nutria populations in urban areas, increasing the potential for conflicts between nutria and humans. Nutria attacks have been reported in isolated cases, and nutria are rodents that carry a variety of transmittable parasites and pathogens. It has also been confirmed that significant regional nutria herbivory damage does occur at some locations. Fortunately, it has become evident through the course of this assessment that a strong regional interest to address the nutria problem exists. A wide variety of agencies and organizations across the region are being negatively impacted by nutria, and these entities are ready to move forward to develop a feasible solution. To date, small-scale nutria management and eradication efforts have been somewhat effective temporarily, but a more permanent solution requires that the situation be addressed on a much larger scale. Due to the long period of time since the initial nutria introduction, the extent of current regional nutria populations, and the changing climate patterns, a long-term effort will likely be required to effectively address the regional nutria issue. The most immediate management need is to develop an official regional nutria management plan with the focus of greatly reducing the amount of damage being caused by this invasive rodent and preventing further population growth and expansion. The effectiveness of initial management efforts will shed light on how to adapt management strategies in the future and whether or not regional eradication is a feasible option. Continued nutria research and the development of coordinated management efforts at the regional scale are vital in order to bring the current regional nutria problem under control. The CLR at PSU has developed initial recommendations to help guide the process of determining how to most effectively manage nutria in the Pacific Northwest. First and foremost, funding sources for continued work on the regional nutria problem must be found. Once funding is secured, the development of an official nutria regional management plan is crucial. Priorities connected with the management plan would include creating an early detection rapid response plan, identifying best management practices, initiating a pilot eradication program, and identifying priority research needs. Potential research studies include a long-term pilot eradication project at the watershed level, relationships between climate change and regional nutria dispersal, and the dynamics of nutria-muskrat interactions. It is also evident that further coordination between local, state, and federal agencies is necessary to delegate responsibilities and keep all parties updated. The creation of a central regional database and appropriate agency protocols could be used to collect information about nutria damage and associated economic impacts. Current laws and regulations pertaining to nutria should be enforced and possibly updated so that Oregon and Washington laws are uniform. Finally, it is important to inform the public about current nutria issues and utilize resources the general public can potentially provide. Title: Report on Nutria Management and Research in the Pacific Northwest Author: Sheffels, Trevor Robert, Sytsma, Mark Year: 2007 The nutria (Myocastor coypus) is a large semi-aquatic mammal native to South America that has been introduced to numerous countries around the world, primarily for fur farming. Nutria were introduced in Oregon and Washington in the 1930s, and feral populations were documented in 1943. Populations are known to be expanding in both Oregon and Washington, and regional nutria damage and nuisance complaints have increased in recent years. Most of the extensive damage caused by nutria is a direct result of feeding and burrowing, but nutria are also capable of transporting parasites and pathogens transmittable to humans, livestock, and pets. Although several past regional and local nutria research and management projects have been identified, there is a shortage of nutria information from the Pacific Northwest considering that the species has been present in the region for approximately seventy years. The Center for Lakes and Reservoirs (CLR) at Portland State University (PSU), in partnership with several local, state, and federal agencies, has taken the lead in addressing the regional nutria problem. Activities completed to date include a regional nutria management workshop, the ongoing development of a regional nutria distribution/density map, and a research project to analyze the impact of nutria herbivory on regional riparian wetland habitat restoration projects. In addition, the CLR at PSU is participating in the development of the national Aquatic Nuisance Species Task Force nutria management plan. This initial assessment of the current nutria situation in the Pacific Northwest conducted by the CLR at PSU has revealed that regional nutria problems are more extensive than previously realized. Nutria sightings have now been confirmed from the Canadian border to near the southern border of Oregon, confirming a larger range than was previously known. It was also found that the main nutria issues in the Pacific Northwest differ from the main nutria issues in Louisiana and Maryland. For example, the most significant category of regional nutria damage appears to be the destruction of water control structures and associated erosion caused by nutria burrowing, as opposed to nutria herbivory damage in Louisiana and Maryland. Another unique situation in the Pacific Northwest is the high density of nutria populations in urban areas, increasing the potential for conflicts between nutria and humans. Nutria attacks have been reported in isolated cases, and nutria are rodents that carry a variety of transmittable parasites and pathogens. It has also been confirmed that significant regional nutria herbivory damage does occur at some locations. Fortunately, it has become evident through the course of this assessment that a strong regional interest to address the nutria problem exists. A wide variety of agencies and organizations across the region are being negatively impacted by nutria, and these entities are ready to move forward to develop a feasible solution. To date, small-scale nutria management and eradication efforts have been somewhat effective temporarily, but a more permanent solution requires that the situation be addressed on a much larger scale. Due to the long period of time since the initial nutria introduction, the extent of current regional nutria populations, and the changing climate patterns, a long-term effort will likely be required to effectively address the regional nutria issue. The most immediate management need is to develop an official regional nutria management plan with the focus of greatly reducing the amount of damage being caused by this invasive rodent and preventing further population growth and expansion. The effectiveness of initial management efforts will shed light on how to adapt management strategies in the future and whether or not regional eradication is a feasible option. Continued nutria research and the development of coordinated management efforts at the regional scale are vital in order to bring the current regional nutria problem under control. The CLR at PSU has developed initial recommendations to help guide the process of determining how to most effectively manage nutria in the Pacific Northwest. First and foremost, funding sources for continued work on the regional nutria problem must be found. Once funding is secured, the development of an official nutria regional management plan is crucial. Priorities connected with the management plan would include creating an early detection rapid response plan, identifying best management practices, initiating a pilot eradication program, and identifying priority research needs. Potential research studies include a long-term pilot eradication project at the watershed level, relationships between climate change and regional nutria dispersal, and the dynamics of nutria-muskrat interactions. It is also evident that further coordination between local, state, and federal agencies is necessary to delegate responsibilities and keep all parties updated. The creation of a central regional database and appropriate agency protocols could be used to collect information about nutria damage and associated economic impacts. Current laws and regulations pertaining to nutria should be enforced and possibly updated so that Oregon and Washington laws are uniform. Finally, it is important to inform the public about current nutria issues and utilize resources the general public can potentially provide. Close

• 318. [Article] The Effect of Temperature on Phenotypes of the Invasive European Green Crab: Physiologic Mechanisms that Facilitate Invasion Success

  Invasion physiology is an emerging field that endeavors to understand the influence of physiological traits on the establishment of non-native species in novel environments. The invasive European green ...

  Citation × Citation Citation Abstract Copy Title: The Effect of Temperature on Phenotypes of the Invasive European Green Crab: Physiologic Mechanisms that Facilitate Invasion Success Author: Kelley, Amanda Year: 2013 Invasion physiology is an emerging field that endeavors to understand the influence of physiological traits on the establishment of non-native species in novel environments. The invasive European green crab,Carcinus maenas, is one of the world's most successful aquatic invaders, and is currently distributed across temperate marine ecosystems globally. The work presented here explored the thermal physiology of this species, and has highlighted several physiological traits that have likely influenced establishment success. Intraspecific comparisons of crabs sampled from the northern and southern edges of their recipient, or invaded range on the west coast of North America have identified both organismal and cellular physiological difference with respect to upper and lower thermal tolerances. Crabs sampled from British Columbia, Canada (BC) had a significantly lower mean upper thermal tolerance threshold and heat shock protein synthesis, Hsp70, compared to their warm acclimated conspecifics sampled from California (CA). These differential physiologic responses may be rooted in the disparate natural thermal habitats that each population occupies within their respective environments. The ability of this species to extend its current range limits was also investigated. Range expansion to the south has been limited, and is likely restricted by this species lack of adaptation to warmer temperatures. Because range expansion has been chiefly northward, characterizing this species' response to cold stress can identify whether colder temperatures poleward may limit further range expansion. Cold tolerance capacity was determined in the laboratory, and crabs sampled from Vancouver Island, British Columbia were able to withstand the over-wintering thermal regime that occurs in Sitka, Alaska, a site that is currently beyond the range limits of this species. Furthermore, intraspecific assessments found that the cold acclimated BC population exposed to cold shock significantly down regulated protein levels of cyclin D1, cell cycle modulator. Distinct differences in carapace width (CW) were detected along the thermal gradient present in the green crabs' range. This variation in body size was utilized to the test the temperature size rule hypothesis for ectotherms. Simply stated, the temperature size rule is the tendency for ectotherms to develop slower but mature to a larger body sizes at cooler temperatures. The results supported this hypothesis as crabs sampled from the warm portion of the range were found to be smaller than crabs sampled from the colder portion of the range. This pattern was detected along the native range as well. Differences in body size have the potential to influence the scope of invasion; larger individuals are generally more fecund and longer lived, which can increase both the intensity and frequency of larval dispersal that could further propel range expansion. The physiologic properties that the green crab possesses which may influence invasion success were examined using peer-reviewed literature with the aim of determining if these physiological traits confer invasion success across taxa. This analysis tested four hypotheses: 1) Broad geographic temperature tolerances (thermal width) confer a higher upper thermal tolerance threshold when comparing invasive and native species. 2) The upper thermal extreme experienced in nature is correlated with upper thermal tolerance threshold. 3) Protein chaperone expression, a cellular mechanism underlying thermal tolerance threshold, is greater in invasive organisms than in native ones. 4) Acclimation to higher temperatures can promote a greater range of thermal tolerance for invasives compared to natives. These preliminary results generally support the four stated hypotheses, and provide a solid foundation for further studies to explore and identify physiologic traits that facilitate invasion success. Overall, these studies investigated the thermal physiology ofCarcinus maenasfrom an invasive metapopulation and have brought about significant advances in our understanding of what physiologic traits correlate to invasion success in this species. In addition, the data presented here can aid resource managers in identifying habitats, based on thermal tolerance measurements that fit the criteria for invasion. Understanding how invasive organisms vary with respect to thermal tolerance can aid our understanding the patterns and processes of species invasions. Title: The Effect of Temperature on Phenotypes of the Invasive European Green Crab: Physiologic Mechanisms that Facilitate Invasion Success Author: Kelley, Amanda Year: 2013 Invasion physiology is an emerging field that endeavors to understand the influence of physiological traits on the establishment of non-native species in novel environments. The invasive European green crab,Carcinus maenas, is one of the world's most successful aquatic invaders, and is currently distributed across temperate marine ecosystems globally. The work presented here explored the thermal physiology of this species, and has highlighted several physiological traits that have likely influenced establishment success. Intraspecific comparisons of crabs sampled from the northern and southern edges of their recipient, or invaded range on the west coast of North America have identified both organismal and cellular physiological difference with respect to upper and lower thermal tolerances. Crabs sampled from British Columbia, Canada (BC) had a significantly lower mean upper thermal tolerance threshold and heat shock protein synthesis, Hsp70, compared to their warm acclimated conspecifics sampled from California (CA). These differential physiologic responses may be rooted in the disparate natural thermal habitats that each population occupies within their respective environments. The ability of this species to extend its current range limits was also investigated. Range expansion to the south has been limited, and is likely restricted by this species lack of adaptation to warmer temperatures. Because range expansion has been chiefly northward, characterizing this species' response to cold stress can identify whether colder temperatures poleward may limit further range expansion. Cold tolerance capacity was determined in the laboratory, and crabs sampled from Vancouver Island, British Columbia were able to withstand the over-wintering thermal regime that occurs in Sitka, Alaska, a site that is currently beyond the range limits of this species. Furthermore, intraspecific assessments found that the cold acclimated BC population exposed to cold shock significantly down regulated protein levels of cyclin D1, cell cycle modulator. Distinct differences in carapace width (CW) were detected along the thermal gradient present in the green crabs' range. This variation in body size was utilized to the test the temperature size rule hypothesis for ectotherms. Simply stated, the temperature size rule is the tendency for ectotherms to develop slower but mature to a larger body sizes at cooler temperatures. The results supported this hypothesis as crabs sampled from the warm portion of the range were found to be smaller than crabs sampled from the colder portion of the range. This pattern was detected along the native range as well. Differences in body size have the potential to influence the scope of invasion; larger individuals are generally more fecund and longer lived, which can increase both the intensity and frequency of larval dispersal that could further propel range expansion. The physiologic properties that the green crab possesses which may influence invasion success were examined using peer-reviewed literature with the aim of determining if these physiological traits confer invasion success across taxa. This analysis tested four hypotheses: 1) Broad geographic temperature tolerances (thermal width) confer a higher upper thermal tolerance threshold when comparing invasive and native species. 2) The upper thermal extreme experienced in nature is correlated with upper thermal tolerance threshold. 3) Protein chaperone expression, a cellular mechanism underlying thermal tolerance threshold, is greater in invasive organisms than in native ones. 4) Acclimation to higher temperatures can promote a greater range of thermal tolerance for invasives compared to natives. These preliminary results generally support the four stated hypotheses, and provide a solid foundation for further studies to explore and identify physiologic traits that facilitate invasion success. Overall, these studies investigated the thermal physiology ofCarcinus maenasfrom an invasive metapopulation and have brought about significant advances in our understanding of what physiologic traits correlate to invasion success in this species. In addition, the data presented here can aid resource managers in identifying habitats, based on thermal tolerance measurements that fit the criteria for invasion. Understanding how invasive organisms vary with respect to thermal tolerance can aid our understanding the patterns and processes of species invasions. Close

• 319. [Article] Examination of Human Impacts on the Biodiversity and Ecology of Lichen and Moss Communities

  Globally, more than half of the world's population is living in urban areas and it is well accepted that human activities (e.g. climate warming, pollution, landscape homogenization) pose a multitude of ...

  Citation × Citation Citation Abstract Copy Title: Examination of Human Impacts on the Biodiversity and Ecology of Lichen and Moss Communities Author: Prather, Hannah Marie Year: 2017 Globally, more than half of the world's population is living in urban areas and it is well accepted that human activities (e.g. climate warming, pollution, landscape homogenization) pose a multitude of threats to ecosystems. Largely, human-related impacts on biodiversity will hold consequences for larger ecological processes and research looking into human impacts on sensitive epiphytic lichen and moss communities is an emerging area of research. While seemingly small, lichen and moss communities exist on nearly every terrestrial ecosystem on Earth and contribute to whole-system processes (e.g. hydrology, mineral cycling, food web energetics) worldwide. To further examine human impacts on epiphytic communities, I conducted three studies examining urbanization and climate warming effects on epiphytic lichen and moss biodiversity and ecology. In the first study I revisited a historic urban lichen community study to assess how urban lichen communities have responded to regional air quality changes occurring over the last nearly two decades. I further investigated, for the first time, the biodiversity of urban tree canopy-dwelling lichen communities in a native coniferous tree species, Pseudotsuga menziesii. I found that urban parks and forested areas harbor a species rich community of lichens epiphytes. Further, I found evidence for the distinct homogenization of urban epiphytic lichen communities, suggesting that expanding beyond simplistic measures of biodiversity to consider community composition and functional biodiversity may be necessary when assessing the ecology and potential ecosystem services of epiphyte communites within urbanizing landscapes. Next, I present the first tall tree canopy study across a regional gradient of urbanization near Portland, Oregon, USA. I found that tall tree canopy epiphyte communities change dramatically along gradients of increasing urbanization, most notably by the transitioning of species functional groups from sensitive, oligotrophic species to a dominance of urban-tolerant, eutrophic species. The implications these dramatic shifts in species composition have on essential PNW ecosystem processes, like N-fixation and canopy microclimate regulation, is still not well understood and is difficult to formally evaluate. However, I find strong evidence that native conifer trees in urban areas may provide a diversity of essential ecosystem services, including providing stratified habitat for epiphyte communities and their associated micro arthropod communities and the scavenging of atmospherically deposited nutrients. Future work is needed to understand how losses in canopy N fixation and species with large biomass (both lichens and bryophytes) will affect nutrient and hydrologic cycling in the PNW region, which continue to undergo rapid growth and urbanization. The final chapter investigates the impacts of passive warming by Open Top Chambers (OTCs) in moss-dominated ecosystems located on the Western Antarctic Peninsula, an area of increasing climate warming. I compared species-specific temperature effects, moss canopy morphology, sexual reproductive effort and invertebrate communities between OTC and control moss communities for two moss species, Polytrichastrum alpinum and Sanionia uncinata, that make up over 65% of the terrestrial vegetative cover in the area. I found distinct reproductive shifts in P. alpinum under passive warming compared to controls. Moss communities under warming also had substantially larger total invertebrate communities than those in control moss communities, and invertebrate communities were significantly affected by moss species and moss reproductive effort. Further, substantial species-specific thermal differences among contiguous patches of these dominant moss species were revealed. These results suggest that continued warming will differentially impact the reproductive output of Antarctic moss species and is likely to dramatically alter terrestrial ecosystems dynamics from the bottom up. This combined work provides a diverse contribution to the field of epiphyte ecology and biology by providing new insights on how human impacts will affect epiphyte lichen and moss communities across diverse ecosystems, in light of a rapidly changing planet. Title: Examination of Human Impacts on the Biodiversity and Ecology of Lichen and Moss Communities Author: Prather, Hannah Marie Year: 2017 Globally, more than half of the world's population is living in urban areas and it is well accepted that human activities (e.g. climate warming, pollution, landscape homogenization) pose a multitude of threats to ecosystems. Largely, human-related impacts on biodiversity will hold consequences for larger ecological processes and research looking into human impacts on sensitive epiphytic lichen and moss communities is an emerging area of research. While seemingly small, lichen and moss communities exist on nearly every terrestrial ecosystem on Earth and contribute to whole-system processes (e.g. hydrology, mineral cycling, food web energetics) worldwide. To further examine human impacts on epiphytic communities, I conducted three studies examining urbanization and climate warming effects on epiphytic lichen and moss biodiversity and ecology. In the first study I revisited a historic urban lichen community study to assess how urban lichen communities have responded to regional air quality changes occurring over the last nearly two decades. I further investigated, for the first time, the biodiversity of urban tree canopy-dwelling lichen communities in a native coniferous tree species, Pseudotsuga menziesii. I found that urban parks and forested areas harbor a species rich community of lichens epiphytes. Further, I found evidence for the distinct homogenization of urban epiphytic lichen communities, suggesting that expanding beyond simplistic measures of biodiversity to consider community composition and functional biodiversity may be necessary when assessing the ecology and potential ecosystem services of epiphyte communites within urbanizing landscapes. Next, I present the first tall tree canopy study across a regional gradient of urbanization near Portland, Oregon, USA. I found that tall tree canopy epiphyte communities change dramatically along gradients of increasing urbanization, most notably by the transitioning of species functional groups from sensitive, oligotrophic species to a dominance of urban-tolerant, eutrophic species. The implications these dramatic shifts in species composition have on essential PNW ecosystem processes, like N-fixation and canopy microclimate regulation, is still not well understood and is difficult to formally evaluate. However, I find strong evidence that native conifer trees in urban areas may provide a diversity of essential ecosystem services, including providing stratified habitat for epiphyte communities and their associated micro arthropod communities and the scavenging of atmospherically deposited nutrients. Future work is needed to understand how losses in canopy N fixation and species with large biomass (both lichens and bryophytes) will affect nutrient and hydrologic cycling in the PNW region, which continue to undergo rapid growth and urbanization. The final chapter investigates the impacts of passive warming by Open Top Chambers (OTCs) in moss-dominated ecosystems located on the Western Antarctic Peninsula, an area of increasing climate warming. I compared species-specific temperature effects, moss canopy morphology, sexual reproductive effort and invertebrate communities between OTC and control moss communities for two moss species, Polytrichastrum alpinum and Sanionia uncinata, that make up over 65% of the terrestrial vegetative cover in the area. I found distinct reproductive shifts in P. alpinum under passive warming compared to controls. Moss communities under warming also had substantially larger total invertebrate communities than those in control moss communities, and invertebrate communities were significantly affected by moss species and moss reproductive effort. Further, substantial species-specific thermal differences among contiguous patches of these dominant moss species were revealed. These results suggest that continued warming will differentially impact the reproductive output of Antarctic moss species and is likely to dramatically alter terrestrial ecosystems dynamics from the bottom up. This combined work provides a diverse contribution to the field of epiphyte ecology and biology by providing new insights on how human impacts will affect epiphyte lichen and moss communities across diverse ecosystems, in light of a rapidly changing planet. Close