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• 1. [Article] Neurobiology of Seasonal Life-history Transitions

  Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such ...

  Citation × Citation Citation Abstract Copy Title: Neurobiology of Seasonal Life-history Transitions Author: Lucas, Ashley Rae Year: 2015 Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected male and female snakes in different migratory stages during the spring and fall. Brains were processed for AVT and NPY immunohistochemistry and the total number of immunoreactive (-ir) cells quantified for each individual. As predicted, males had significantly more AVT-ir cells in the preoptic area and bed nucleus of the stria terminalis, brain regions important for courtship behavior, during the spring mating season compared to the fall. Females had significantly more AVT-ir cells in the preoptic area during the spring compared to the fall and, surprisingly, did not exhibit seasonal changes in NPY. In contrast, males had significantly more NPY-ir cells in the cortex, a region important for spatial memory, and in the posterior hypothalamus during the fall compared to the spring, which likely reflects increased feeding behavior during the summer foraging period. Neither AVT- nor NPY-ir cell number varied significantly with migratory status, indicating that seasonal changes in these neuropeptides are not directly related to migration. I then asked if the observed seasonal changes in AVT and NPY in males and females are related to the transition from reproductive to non-reproductive states. Compared to courting males, non-courting males had significantly more AVT-ir cells in the supraoptic nucleus and more NPY-ir cells in the cortex. AVT- and NPY-ir cells did not differ between unmated and mated females. Collectively, my results suggest that AVT and NPY play a role in regulating seasonal transitions in male reproductive behavior, rather than regulating migration per se. Further, these data indicate that both AVT and NPY are regulating reproductive behavior differently in males versus females. These data provide the framework for future studies examining the mechanisms regulating transitions between reproductive, migratory and foraging behaviors. Title: Neurobiology of Seasonal Life-history Transitions Author: Lucas, Ashley Rae Year: 2015 Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected male and female snakes in different migratory stages during the spring and fall. Brains were processed for AVT and NPY immunohistochemistry and the total number of immunoreactive (-ir) cells quantified for each individual. As predicted, males had significantly more AVT-ir cells in the preoptic area and bed nucleus of the stria terminalis, brain regions important for courtship behavior, during the spring mating season compared to the fall. Females had significantly more AVT-ir cells in the preoptic area during the spring compared to the fall and, surprisingly, did not exhibit seasonal changes in NPY. In contrast, males had significantly more NPY-ir cells in the cortex, a region important for spatial memory, and in the posterior hypothalamus during the fall compared to the spring, which likely reflects increased feeding behavior during the summer foraging period. Neither AVT- nor NPY-ir cell number varied significantly with migratory status, indicating that seasonal changes in these neuropeptides are not directly related to migration. I then asked if the observed seasonal changes in AVT and NPY in males and females are related to the transition from reproductive to non-reproductive states. Compared to courting males, non-courting males had significantly more AVT-ir cells in the supraoptic nucleus and more NPY-ir cells in the cortex. AVT- and NPY-ir cells did not differ between unmated and mated females. Collectively, my results suggest that AVT and NPY play a role in regulating seasonal transitions in male reproductive behavior, rather than regulating migration per se. Further, these data indicate that both AVT and NPY are regulating reproductive behavior differently in males versus females. These data provide the framework for future studies examining the mechanisms regulating transitions between reproductive, migratory and foraging behaviors. Close

• 2. [Article] Cascades Island Lamprey Passage Structure: Evaluating Passage and Migration Following Structure Modifications

  Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are ...

  Citation × Citation Citation Abstract Copy Title: Cascades Island Lamprey Passage Structure: Evaluating Passage and Migration Following Structure Modifications Author: Lopez-Johnston, Siena Marie Year: 2014 Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are threatened severely by a lack of passage at mainstem dams, lamprey specific passage structures have been designed and constructed to address the problem. The Cascades Island Lamprey Passage Structure (LPS) at Bonneville Dam is the longest and steepest structure of its type, following the addition of an exit pipe which allows lampreys to travel from the tailrace of the dam to the forebay. The intent of this study was to assess lamprey use of the structure and whether the structure hinders lamprey migration to subsequent dams. The study was carried out during the 2013 migration season. The study used three different treatment groups of lampreys released on five dates spanning the migration season (n=75 lamprey). Two of these groups (n=50), with different tagging methods, were released directly into the LPS to assess passage success, travel time, and tagging effect. The third group (n=25) was released into the forebay to test whether the structure impedes migration upstream. Fish were monitored via receiver arrays on the LPS and at dams on the river system. Overall passage efficiency was 74% (37 of 50 used the CI LPS successfully). Mean travel time to navigate the structure was 12 h. Fish size had no significant effect on travel time in the LPS. Water temperature had a significant effect on travel time in the LPS. There was no statistically significant effect of tagging on passage efficiency or travel time. The groups that used the LPS performed slightly better migrating upstream to the next dam than the group that bypassed the structure, but the difference was not significant. The groups that used the LPS traveled to more subsequent dams upstream than did the group that bypassed the LPS. It can be concluded that lamprey passed the structure successfully. Temperature (proxy for seasonality) had an effect on travel time in the LPS; however fish size and tagging had no effect. The LPS does not affect the ability of migrating lampreys to continue migration to subsequent dams. Such findings have important implications for management of lamprey in the region. Title: Cascades Island Lamprey Passage Structure: Evaluating Passage and Migration Following Structure Modifications Author: Lopez-Johnston, Siena Marie Year: 2014 Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are threatened severely by a lack of passage at mainstem dams, lamprey specific passage structures have been designed and constructed to address the problem. The Cascades Island Lamprey Passage Structure (LPS) at Bonneville Dam is the longest and steepest structure of its type, following the addition of an exit pipe which allows lampreys to travel from the tailrace of the dam to the forebay. The intent of this study was to assess lamprey use of the structure and whether the structure hinders lamprey migration to subsequent dams. The study was carried out during the 2013 migration season. The study used three different treatment groups of lampreys released on five dates spanning the migration season (n=75 lamprey). Two of these groups (n=50), with different tagging methods, were released directly into the LPS to assess passage success, travel time, and tagging effect. The third group (n=25) was released into the forebay to test whether the structure impedes migration upstream. Fish were monitored via receiver arrays on the LPS and at dams on the river system. Overall passage efficiency was 74% (37 of 50 used the CI LPS successfully). Mean travel time to navigate the structure was 12 h. Fish size had no significant effect on travel time in the LPS. Water temperature had a significant effect on travel time in the LPS. There was no statistically significant effect of tagging on passage efficiency or travel time. The groups that used the LPS performed slightly better migrating upstream to the next dam than the group that bypassed the structure, but the difference was not significant. The groups that used the LPS traveled to more subsequent dams upstream than did the group that bypassed the LPS. It can be concluded that lamprey passed the structure successfully. Temperature (proxy for seasonality) had an effect on travel time in the LPS; however fish size and tagging had no effect. The LPS does not affect the ability of migrating lampreys to continue migration to subsequent dams. Such findings have important implications for management of lamprey in the region. Close

• 3. [Article] Has Capitalism Lost its Puritan Spirit? What do Recent WVS Data Say about Religiosity and Work Values?

  This paper tests the arguments of social theorists about the changing spirit of capitalism in countries with different levels of economic development using the recent World Values Survey (WVS). Max Weber ...

  Citation × Citation Citation Abstract Copy Title: Has Capitalism Lost its Puritan Spirit? What do Recent WVS Data Say about Religiosity and Work Values? Author: Bozkurt, Veysel, Yeşilada, Birol A. Year: 2017 This paper tests the arguments of social theorists about the changing spirit of capitalism in countries with different levels of economic development using the recent World Values Survey (WVS). Max Weber claimed that the Protestant Ethic was the spirit of capitalism for salvation and improved economic development in Europe. During the last 40 years, sociologists, such as Bell and Bauman, have claimed that capitalism has started to lose its puritan spirit and a new secular/hedonist personality type has emerged as the new characteristic of post-industrial/ consumer capitalism. The data show that religiosity and work values decline but leisure and self-expression values increase in knowledge economy-based post-industrial societies and late consumer capitalism has a new spirit which is the polar opposite of the Protestant ethic. However, the puritan spirit has not totally disappeared from the world but has migrated to newly industrializing societies. Title: Has Capitalism Lost its Puritan Spirit? What do Recent WVS Data Say about Religiosity and Work Values? Author: Bozkurt, Veysel, Yeşilada, Birol A. Year: 2017 This paper tests the arguments of social theorists about the changing spirit of capitalism in countries with different levels of economic development using the recent World Values Survey (WVS). Max Weber claimed that the Protestant Ethic was the spirit of capitalism for salvation and improved economic development in Europe. During the last 40 years, sociologists, such as Bell and Bauman, have claimed that capitalism has started to lose its puritan spirit and a new secular/hedonist personality type has emerged as the new characteristic of post-industrial/ consumer capitalism. The data show that religiosity and work values decline but leisure and self-expression values increase in knowledge economy-based post-industrial societies and late consumer capitalism has a new spirit which is the polar opposite of the Protestant ethic. However, the puritan spirit has not totally disappeared from the world but has migrated to newly industrializing societies. Close

• 4. [Article] Characterization and Comparative Analysis of 2,4-Toluene Diisocyanate and 1,6-Hexamethylene Diisocyanate Haptenated Human Serum Albumin and Hemoglobin

  Diisocyanates (dNCOs) are lowmolecularweight chemical sensitizers that reactwith autologous proteins to produce neoantigens. dNCO-haptenated proteins have been used as immunogens for generation of dNCO-specific ...

  Citation × Citation Citation Abstract Copy Title: Characterization and Comparative Analysis of 2,4-Toluene Diisocyanate and 1,6-Hexamethylene Diisocyanate Haptenated Human Serum Albumin and Hemoglobin Author: Mhike, Morgen, Chipinda, Ita, Law, Brandon F., Bledsoe, Toni A., Lemons, Angela R., Nayak, Ajay P., Green, Brett J., Beezhold, Donald H., Simoyi, Reuben H., Siegel, Paul D. Year: 2016 Diisocyanates (dNCOs) are lowmolecularweight chemical sensitizers that reactwith autologous proteins to produce neoantigens. dNCO-haptenated proteins have been used as immunogens for generation of dNCO-specific antibodies and as antigens to screen for dNCO-specific antibodies in exposed individuals. Detection of dNCOspecific antibodies in exposed individuals for diagnosis of dNCO asthma has been hampered by poor sensitivities of the assay methods in that specific IgE can only be detected in approximately 25% of the dNCO asthmatics. Apart from characterization of the conjugates used for these immunoassays, the choice of the carrier protein and the dNCO used are important parameters that can influence the detection of dNCO-specific antibodies. Human serum albumin (HSA) is the most common carrier protein used for detection of dNCO specific-IgE and -IgG but the immunogenicity and/or antigenicity of other proteins that may bemodified by dNCO in vivo is not well documented. In the current study, 2,4-toluene diisocyanate (TDI) and 1,6-hexamethylene diisocyanate (HDI) were reacted with HSA and human hemoglobin (Hb) and the resultant adducts were characterized by (i) HPLC quantification of the diamine produced from acid hydrolysis of the adducts, (ii) 2,4,6-trinitrobenzene sulfonic acid (TNBS) assay to assess extent of cross-linking, (iii) electrophoretic migration in polyacrylamide gels to analyze intra- and inter-molecular cross-linking, and (iv) evaluation of antigenicity using a monoclonal antibody developed previously to TDI conjugated to Keyhole limpet hemocyanin (KLH). Concentration-dependent increases in the amount of dNCO bound to HDI and TDI, cross-linking, migration in gels, and antibody-binding were observed. TDI reactivity with both HSA and Hb was significantly higher than HDI. Hb–TDI antigenicity was approximately 30% that of HSA–TDI. In conclusion, this data suggests that both, the extent of haptenation as well as the degree of cross-linking differs between the two diisocyanate species studied, which may influence their relative immunogenicity and/or antigenicity. Title: Characterization and Comparative Analysis of 2,4-Toluene Diisocyanate and 1,6-Hexamethylene Diisocyanate Haptenated Human Serum Albumin and Hemoglobin Author: Mhike, Morgen, Chipinda, Ita, Law, Brandon F., Bledsoe, Toni A., Lemons, Angela R., Nayak, Ajay P., Green, Brett J., Beezhold, Donald H., Simoyi, Reuben H., Siegel, Paul D. Year: 2016 Diisocyanates (dNCOs) are lowmolecularweight chemical sensitizers that reactwith autologous proteins to produce neoantigens. dNCO-haptenated proteins have been used as immunogens for generation of dNCO-specific antibodies and as antigens to screen for dNCO-specific antibodies in exposed individuals. Detection of dNCOspecific antibodies in exposed individuals for diagnosis of dNCO asthma has been hampered by poor sensitivities of the assay methods in that specific IgE can only be detected in approximately 25% of the dNCO asthmatics. Apart from characterization of the conjugates used for these immunoassays, the choice of the carrier protein and the dNCO used are important parameters that can influence the detection of dNCO-specific antibodies. Human serum albumin (HSA) is the most common carrier protein used for detection of dNCO specific-IgE and -IgG but the immunogenicity and/or antigenicity of other proteins that may bemodified by dNCO in vivo is not well documented. In the current study, 2,4-toluene diisocyanate (TDI) and 1,6-hexamethylene diisocyanate (HDI) were reacted with HSA and human hemoglobin (Hb) and the resultant adducts were characterized by (i) HPLC quantification of the diamine produced from acid hydrolysis of the adducts, (ii) 2,4,6-trinitrobenzene sulfonic acid (TNBS) assay to assess extent of cross-linking, (iii) electrophoretic migration in polyacrylamide gels to analyze intra- and inter-molecular cross-linking, and (iv) evaluation of antigenicity using a monoclonal antibody developed previously to TDI conjugated to Keyhole limpet hemocyanin (KLH). Concentration-dependent increases in the amount of dNCO bound to HDI and TDI, cross-linking, migration in gels, and antibody-binding were observed. TDI reactivity with both HSA and Hb was significantly higher than HDI. Hb–TDI antigenicity was approximately 30% that of HSA–TDI. In conclusion, this data suggests that both, the extent of haptenation as well as the degree of cross-linking differs between the two diisocyanate species studied, which may influence their relative immunogenicity and/or antigenicity. Close

• 5. [Article] Drift of Plumes in the Mantle

  We quantified the fixity of mantle plumes relative to the mantle in high Rayleigh number numerical thermal convection with radially- and temperature-dependent viscosity structures in a 3D spherical shell ...

  Citation × Citation Citation Abstract Copy Title: Drift of Plumes in the Mantle Author: Brown, Luke Douglas Year: 2015 We quantified the fixity of mantle plumes relative to the mantle in high Rayleigh number numerical thermal convection with radially- and temperature-dependent viscosity structures in a 3D spherical shell geometry. The relative velocities between plumes and the mantle increased with increasing Rayleigh number. Net migration rates of plumes vary from ~0.016-0.053 °/Myr, and differential plume velocities can be up to ~25% of past- and present-day rates of net lithospheric rotation. Individual plumes migrate on average at ~0.0617-0.223 °/Myr for Rayleigh numbers between 1·107 and 2·108. We compared the ratio of plume velocity to horizontal average velocity (a) at the surface and (b) at mid-mantle for experiments with Rayleigh number between 5·107 and 2·108, which were (a) ~0.15 and (b) ~0.35. Additionally, we plotted the mean migration rates of plumes against Rayleigh number and found that a linear fit had a greater R2 value than a power law fit. There is a transition in the long-wavelength structure of convection from degree-2 to degree-1 poloidally dominant motion between Ra = 1·107 and Ra = 2·108 where thermal upwellings change from dominantly sheet-like to dominantly plume-like. Future studies should investigate whether the scaling of plume velocities with vigor of convection depends on the mode of convection. We find that all cases produce long-lived plume-like features which generate from a thermal boundary layer at the core-mantle boundary, and persist for more than 80 Myr. On average, the lifespan of mantle plumes decreased with increasing Rayleigh number. Our studies suggest that hotspots may be an imperfect proxy for a lower mantle reference frame. Title: Drift of Plumes in the Mantle Author: Brown, Luke Douglas Year: 2015 We quantified the fixity of mantle plumes relative to the mantle in high Rayleigh number numerical thermal convection with radially- and temperature-dependent viscosity structures in a 3D spherical shell geometry. The relative velocities between plumes and the mantle increased with increasing Rayleigh number. Net migration rates of plumes vary from ~0.016-0.053 °/Myr, and differential plume velocities can be up to ~25% of past- and present-day rates of net lithospheric rotation. Individual plumes migrate on average at ~0.0617-0.223 °/Myr for Rayleigh numbers between 1·107 and 2·108. We compared the ratio of plume velocity to horizontal average velocity (a) at the surface and (b) at mid-mantle for experiments with Rayleigh number between 5·107 and 2·108, which were (a) ~0.15 and (b) ~0.35. Additionally, we plotted the mean migration rates of plumes against Rayleigh number and found that a linear fit had a greater R2 value than a power law fit. There is a transition in the long-wavelength structure of convection from degree-2 to degree-1 poloidally dominant motion between Ra = 1·107 and Ra = 2·108 where thermal upwellings change from dominantly sheet-like to dominantly plume-like. Future studies should investigate whether the scaling of plume velocities with vigor of convection depends on the mode of convection. We find that all cases produce long-lived plume-like features which generate from a thermal boundary layer at the core-mantle boundary, and persist for more than 80 Myr. On average, the lifespan of mantle plumes decreased with increasing Rayleigh number. Our studies suggest that hotspots may be an imperfect proxy for a lower mantle reference frame. Close

• 6. [Article] Intestinal Microbiota Diversity of Pre-Smolt Steelhead (Oncorhynchus mykiss) Across Six Oregon and Washington Hatcheries

  The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, ...

  Citation × Citation Citation Abstract Copy Title: Intestinal Microbiota Diversity of Pre-Smolt Steelhead (Oncorhynchus mykiss) Across Six Oregon and Washington Hatcheries Author: Yildirimer, Christina Carrell Year: 2017 The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, federal and state agencies annually release hundreds of thousands of hatchery-reared fish into the wild. However, accumulating data indicate that hatchery fish have lower fitness in natural environments, and that hatchery rearing negatively influences return rates of anadromous salmonids. Recently, mounting evidence revealed that the richness and diversity of intestinal microbial species influence host health. We examined the gut microbiota of pre-migratory hatchery-reared steelhead (Oncorhynchus mykiss) to assess microbial community diversity. The Cascade Mountains serve as an allopatric border between two distinct clades of steelhead that show significant differences in genomic and mitochondrial diversity. We identified differences in core microbiota of hatchery-reared fish that correlate with this divergent phylogeographic distribution. Steelhead sampled from hatcheries east of the Cascades had overall greater core gut microbiota diversity. These differences were found despite similarities in diet and rearing conditions. In addition to taxonomic variation across the geographic divide, we identified significant differences in metabolic pathways using PICRUSt gene prediction software. Our analysis revealed significant enrichment of genes associated with lipid metabolism in the gut microbiome of western fish. 8 of 19 individual lipid metabolism pathways were more prominent in western populations. Lipids are a vital nutritional component for teleost species involved in migration and subsequent return for spawning in natal environments. We hypothesize that the observed differences in lipid metabolism across this phylogenetic divide results from an increased ability of eastern Cascade (O. m. gairdneri) fish to utilize lipids taken in via the diet. This increased absorption and utilization would make lipids less available for the intestinal microbiota of the eastern fish, as evidenced by the lower abundance of lipid metabolism genes in the east. Our research utilizes information from the microbiome to understand the phenotypic implications occurring in segregated populations of hatchery-reared steelhead, further confirming elements of coevolution between an organism and its internal environment. Title: Intestinal Microbiota Diversity of Pre-Smolt Steelhead (Oncorhynchus mykiss) Across Six Oregon and Washington Hatcheries Author: Yildirimer, Christina Carrell Year: 2017 The Pacific Northwest is known for its once-abundant wild salmonid populations that have been in decline for more than 50 years due to habitat destruction and commercial overexploitation. To compensate, federal and state agencies annually release hundreds of thousands of hatchery-reared fish into the wild. However, accumulating data indicate that hatchery fish have lower fitness in natural environments, and that hatchery rearing negatively influences return rates of anadromous salmonids. Recently, mounting evidence revealed that the richness and diversity of intestinal microbial species influence host health. We examined the gut microbiota of pre-migratory hatchery-reared steelhead (Oncorhynchus mykiss) to assess microbial community diversity. The Cascade Mountains serve as an allopatric border between two distinct clades of steelhead that show significant differences in genomic and mitochondrial diversity. We identified differences in core microbiota of hatchery-reared fish that correlate with this divergent phylogeographic distribution. Steelhead sampled from hatcheries east of the Cascades had overall greater core gut microbiota diversity. These differences were found despite similarities in diet and rearing conditions. In addition to taxonomic variation across the geographic divide, we identified significant differences in metabolic pathways using PICRUSt gene prediction software. Our analysis revealed significant enrichment of genes associated with lipid metabolism in the gut microbiome of western fish. 8 of 19 individual lipid metabolism pathways were more prominent in western populations. Lipids are a vital nutritional component for teleost species involved in migration and subsequent return for spawning in natal environments. We hypothesize that the observed differences in lipid metabolism across this phylogenetic divide results from an increased ability of eastern Cascade (O. m. gairdneri) fish to utilize lipids taken in via the diet. This increased absorption and utilization would make lipids less available for the intestinal microbiota of the eastern fish, as evidenced by the lower abundance of lipid metabolism genes in the east. Our research utilizes information from the microbiome to understand the phenotypic implications occurring in segregated populations of hatchery-reared steelhead, further confirming elements of coevolution between an organism and its internal environment. Close

• 7. [Article] ] To Mother

  Four weeks before the collapse of the Berlin Wall in 1989 an eleven-year-old flees the Soviet Union with her young father. As political refugee determined to eventually settle in the United States they ...

  Citation × Citation Citation Abstract Copy Title: ] To Mother Author: Pfaff-Shalmiyev, Sophia Year: 2015 Four weeks before the collapse of the Berlin Wall in 1989 an eleven-year-old flees the Soviet Union with her young father. As political refugee determined to eventually settle in the United States they hastily abandon the girl's estranged alcoholic mother, future stepmother, their friends and relatives, their collection of books and all but a handful of family photographs. She eventually attempts to seek out and recover the people, ideas and objects lost on that voyage to America by going back to a much changed Russia and stitching together the scattered and forgotten pieces in between her old and new homes through dream-like snapshots. Two decades after her emigration the author examines the concept of bad luck in one's travels, the significance of the number four, ambivalent attachments, learning to mother from a place of abandonment, the familial legacy of escape and the pursuit of wholeness within inconsolable loss. The un-tellability of the story is considered through the lens of Sappho, Bernadette Mayer, Yoko Ono, Roland Barthes, Doris Lessing, Nico and many other surrogate mothers and fathers brought together as a chorus in a multi-vocal, lyric approach. Title: ] To Mother Author: Pfaff-Shalmiyev, Sophia Year: 2015 Four weeks before the collapse of the Berlin Wall in 1989 an eleven-year-old flees the Soviet Union with her young father. As political refugee determined to eventually settle in the United States they hastily abandon the girl's estranged alcoholic mother, future stepmother, their friends and relatives, their collection of books and all but a handful of family photographs. She eventually attempts to seek out and recover the people, ideas and objects lost on that voyage to America by going back to a much changed Russia and stitching together the scattered and forgotten pieces in between her old and new homes through dream-like snapshots. Two decades after her emigration the author examines the concept of bad luck in one's travels, the significance of the number four, ambivalent attachments, learning to mother from a place of abandonment, the familial legacy of escape and the pursuit of wholeness within inconsolable loss. The un-tellability of the story is considered through the lens of Sappho, Bernadette Mayer, Yoko Ono, Roland Barthes, Doris Lessing, Nico and many other surrogate mothers and fathers brought together as a chorus in a multi-vocal, lyric approach. Close

• 8. [Article] Winter Diet of Bobolink, a Long-Distance Migratory Grassland Bird, Inferred from Feather Isotopes

  Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat ...

  Citation × Citation Citation Abstract Copy Title: Winter Diet of Bobolink, a Long-Distance Migratory Grassland Bird, Inferred from Feather Isotopes Author: Renfrew, Rosalind B., Hill, Jason M., Kim, Daniel H., Romanek, Christopher, Perlut, Noah G. Year: 2017 Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat use and diet composition) remains limited, which limits assessment of threats to populations during winter. Bobolink (Dolichonyx oryzivorus) is a year-round grassland obligate and Nearctic-Neotropical migrant that undergoes 2 complete molts each year, including a complete prealternate molt on the South American wintering grounds. This unusual winter molt provides a rare opportunity to examine, using stable isotope analysis, the timing and contribution of foraging resources in the Bobolink diet prior to northbound migration from disparate breeding populations. We compared winter diet composition among 3 breeding populations of Bobolinks and during 3 stages of winter molt using stable carbon isotope ratios. We used mixing models to compare the ratio of carbon-12 to carbon-13 isotope (d13C value) in feathers—grown on the wintering grounds but collected from individuals (n ¼ 105) breeding in Vermont, Nebraska, and North Dakota, USA—to estimate diet during early, middle, and late winter molt. Across the 3 breeding populations, Bobolinks relied on C3 sources for nearly one-third of their diet during the winter molt. Isotope data from feathers collected while growing on the wintering grounds from birds in rice vs. non-rice regions supported our assumption that C3 signatures are primarily due to a rice diet. The proportion of rice consumed was highest during late molt, corresponding with a period of greater rice availability to Bobolinks. Our results demonstrate that rice was a substantial component of the diet throughout the winter molt and was most exploited prior to northbound migration. Research is needed on the potential trade-offs of feeding on abundant cultivated rice, including its nutritional value and associated risks and conflicts from foraging in an agricultural setting. Title: Winter Diet of Bobolink, a Long-Distance Migratory Grassland Bird, Inferred from Feather Isotopes Author: Renfrew, Rosalind B., Hill, Jason M., Kim, Daniel H., Romanek, Christopher, Perlut, Noah G. Year: 2017 Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat use and diet composition) remains limited, which limits assessment of threats to populations during winter. Bobolink (Dolichonyx oryzivorus) is a year-round grassland obligate and Nearctic-Neotropical migrant that undergoes 2 complete molts each year, including a complete prealternate molt on the South American wintering grounds. This unusual winter molt provides a rare opportunity to examine, using stable isotope analysis, the timing and contribution of foraging resources in the Bobolink diet prior to northbound migration from disparate breeding populations. We compared winter diet composition among 3 breeding populations of Bobolinks and during 3 stages of winter molt using stable carbon isotope ratios. We used mixing models to compare the ratio of carbon-12 to carbon-13 isotope (d13C value) in feathers—grown on the wintering grounds but collected from individuals (n ¼ 105) breeding in Vermont, Nebraska, and North Dakota, USA—to estimate diet during early, middle, and late winter molt. Across the 3 breeding populations, Bobolinks relied on C3 sources for nearly one-third of their diet during the winter molt. Isotope data from feathers collected while growing on the wintering grounds from birds in rice vs. non-rice regions supported our assumption that C3 signatures are primarily due to a rice diet. The proportion of rice consumed was highest during late molt, corresponding with a period of greater rice availability to Bobolinks. Our results demonstrate that rice was a substantial component of the diet throughout the winter molt and was most exploited prior to northbound migration. Research is needed on the potential trade-offs of feeding on abundant cultivated rice, including its nutritional value and associated risks and conflicts from foraging in an agricultural setting. Close

• 9. [Article] Using Satellite Observations to Characterize the Response of Estuarine Turbidity Maxima to External Forcing

  This study explores the spatial and temporal character of turbidity maxima in the Columbia River Estuary (CRE) using satellite observations. Surface reflectance data measured by the Moderate Imaging Spectroradiometer ...

  Citation × Citation Citation Abstract Copy Title: Using Satellite Observations to Characterize the Response of Estuarine Turbidity Maxima to External Forcing Author: Hudson, Austin S., Talke, Stefan A., Jay, David A. Year: 2017 This study explores the spatial and temporal character of turbidity maxima in the Columbia River Estuary (CRE) using satellite observations. Surface reflectance data measured by the Moderate Imaging Spectroradiometer (MODIS) were calibrated against in situ measurements of surface turbidity (R2 = 0.85 for 205 measurements). More than 1500 satellite images from 2000 to 2015 were then conditionally sampled to explore the physical processes that drive the spatial distribution of the turbidity field. We find satellite measurements are able to describe seasonal, spring–neap, and spatial features of the estuarine turbidity maxima (ETM) that are not easily observable by other means. System-wide levels of turbidity are most sensitive to river flow and spring–neap tidal range, with a weaker correlation to wind and waves. Maximum surface turbidity is observed in winter during elevated flow from coastal tributaries and remains elevated during the spring freshet of the main stem Columbia. Two ETM with asymmetric along-channel profiles are observed, one in the North Channel and another in the South Channel. Turbidity distributions migrate downstream as tidal range and river flow increase but appear to become topographically trapped near topographic holes at river kilometers 15–20. Hence, depth-sensitive circulation processes like internal asymmetry and gravitational circulation are likely important mechanisms for trapping particles and determining ETM location. These conclusions confirm the theoretical result that along-channel distributions of turbidity should have an asymmetric distribution and emphasize the role of bottom topography. Title: Using Satellite Observations to Characterize the Response of Estuarine Turbidity Maxima to External Forcing Author: Hudson, Austin S., Talke, Stefan A., Jay, David A. Year: 2017 This study explores the spatial and temporal character of turbidity maxima in the Columbia River Estuary (CRE) using satellite observations. Surface reflectance data measured by the Moderate Imaging Spectroradiometer (MODIS) were calibrated against in situ measurements of surface turbidity (R2 = 0.85 for 205 measurements). More than 1500 satellite images from 2000 to 2015 were then conditionally sampled to explore the physical processes that drive the spatial distribution of the turbidity field. We find satellite measurements are able to describe seasonal, spring–neap, and spatial features of the estuarine turbidity maxima (ETM) that are not easily observable by other means. System-wide levels of turbidity are most sensitive to river flow and spring–neap tidal range, with a weaker correlation to wind and waves. Maximum surface turbidity is observed in winter during elevated flow from coastal tributaries and remains elevated during the spring freshet of the main stem Columbia. Two ETM with asymmetric along-channel profiles are observed, one in the North Channel and another in the South Channel. Turbidity distributions migrate downstream as tidal range and river flow increase but appear to become topographically trapped near topographic holes at river kilometers 15–20. Hence, depth-sensitive circulation processes like internal asymmetry and gravitational circulation are likely important mechanisms for trapping particles and determining ETM location. These conclusions confirm the theoretical result that along-channel distributions of turbidity should have an asymmetric distribution and emphasize the role of bottom topography. Close

• 10. [Article] Migration Movement

  All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements ...

  Citation × Citation Citation Abstract Copy Title: Migration Movement Author: Porte, Robert Year: 2016 All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements of their citizens, they end up doing the work of a dam, they generate power and control floods, but in doing so they destroy life and wreck the surrounding space." Justseeds†(excerpt) As the current administration at the time of this writing continues its program of deportation of women and children from the U.S. to their war torn and violent countries of origin, I want not to engage in an art practice that doesn’t consider the sociopolitical climate of our times. Title: Migration Movement Author: Porte, Robert Year: 2016 All†Borders†Are†Temporary "Migration is a phenomenon, not a problem – something that simply is. The right to migrate and to move freely is our human right. When societies restrict or choke off the movements of their citizens, they end up doing the work of a dam, they generate power and control floods, but in doing so they destroy life and wreck the surrounding space." Justseeds†(excerpt) As the current administration at the time of this writing continues its program of deportation of women and children from the U.S. to their war torn and violent countries of origin, I want not to engage in an art practice that doesn’t consider the sociopolitical climate of our times. Close