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• 81. [Article] Climate Change and Shifts in Water Related Ecosystem Services in the Tualatin and Yamhill River Basins

  Water related ecosystem services (WES), such as flow regulation, drinking water supply, temperature regulation, and water recreational activities, are affected by anthropogenic climate change. Forecasting ...

  Citation × Citation Citation Abstract Copy Title: Climate Change and Shifts in Water Related Ecosystem Services in the Tualatin and Yamhill River Basins Author: Chang, Heejun, Anthony, Terrance, Ennaanay, Driss, Sharma, Manu Year: 2011 Water related ecosystem services (WES), such as flow regulation, drinking water supply, temperature regulation, and water recreational activities, are affected by anthropogenic climate change. Forecasting potential shifts in such WES is critical to identifying the form and magnitude of likely impacts. We quantified the levels and values of WES under multiple climate change scenarios in the two watersheds located in the Portland metropolitan area, Oregon, USA using the combination of a hydrologic model Better Assessment Science Integrating point and Non-point Sources - Soil and Water Assessment Tool (BASINS-SWAT) and an ecosystem evaluation model ? Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). Using the Intergovernmental Panel on Climate Change?s AR4 climate change simulation results, we found that there is a slight relative increase in annual water yield, sediment yield, and dissolved phosphorus, but storm peak management does not change substantially by the 2050s. Spatial analysis shows that the locations of hot and cold spots remain relatively stable. It is also shown that there are high spatial and temporal uncertainties associated with climate change projections due to variations in precipitation projections toward the middle of the 21st century. The findings of our study provide useful information for water and land managers in identifying target areas for conservation to best sustain WES provision, use, and value under a range of climate change scenarios. Title: Climate Change and Shifts in Water Related Ecosystem Services in the Tualatin and Yamhill River Basins Author: Chang, Heejun, Anthony, Terrance, Ennaanay, Driss, Sharma, Manu Year: 2011 Water related ecosystem services (WES), such as flow regulation, drinking water supply, temperature regulation, and water recreational activities, are affected by anthropogenic climate change. Forecasting potential shifts in such WES is critical to identifying the form and magnitude of likely impacts. We quantified the levels and values of WES under multiple climate change scenarios in the two watersheds located in the Portland metropolitan area, Oregon, USA using the combination of a hydrologic model Better Assessment Science Integrating point and Non-point Sources - Soil and Water Assessment Tool (BASINS-SWAT) and an ecosystem evaluation model ? Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). Using the Intergovernmental Panel on Climate Change?s AR4 climate change simulation results, we found that there is a slight relative increase in annual water yield, sediment yield, and dissolved phosphorus, but storm peak management does not change substantially by the 2050s. Spatial analysis shows that the locations of hot and cold spots remain relatively stable. It is also shown that there are high spatial and temporal uncertainties associated with climate change projections due to variations in precipitation projections toward the middle of the 21st century. The findings of our study provide useful information for water and land managers in identifying target areas for conservation to best sustain WES provision, use, and value under a range of climate change scenarios. Close

• 82. [Article] Effect of ethanol on thermoregulation in the goldfish, Carassius auratus

  In an attempt to elucidate the mechanism by which ethanol affects vertebrate thermoregulation, the effect of ethanol on temperature selection was studied in the goldfish, Carassius auratus. Ethanol was ...

  Citation × Citation Citation Abstract Copy Title: Effect of ethanol on thermoregulation in the goldfish, Carassius auratus Author: O'Connor, Candace Sharon Year: 1986 In an attempt to elucidate the mechanism by which ethanol affects vertebrate thermoregulation, the effect of ethanol on temperature selection was studied in the goldfish, Carassius auratus. Ethanol was administered to 10 to 15 g fish by mixing it in the water of a temperature gradient. The dose response curve was very steep between 0.5% (v/v) ethanol (no response) and 0.7% (significant lowering of selected temperature in treated fish). Fish were exposed to concentrations of ethanol as high as 1.7%, at which concentration most experimental fish lost their ability to swim upright in the water. At concentrations higher than 0.7%, the magnitude of the effect did not increase with increasing concentration of ethanol; treated animals continued to select temperatures about 2 C below temperatures selected by controls. Experiments alternating exposure to 1.0% ethanol and water showed that the rate of onset and disappearance of the ethanol effect was rapid (within 10 min). Other experiments exposing fish to 1.0% ethanol for up to 3 hr showed that the effect remained stable for this period of time. The thermoregulatory responses of fish are behavioral, and therefore relatively easy to observe and quantify. Ethanol produces a prompt, stable and reproducible depression of selected temperature in the goldfish. Because the temperature at which fish regulate is controlled by a central nervous system set point and not altered by effects on peripheral effector systems, it appears that ethanol may cause hypothermia in goldfish by directly acting to lower the set point. Title: Effect of ethanol on thermoregulation in the goldfish, Carassius auratus Author: O'Connor, Candace Sharon Year: 1986 In an attempt to elucidate the mechanism by which ethanol affects vertebrate thermoregulation, the effect of ethanol on temperature selection was studied in the goldfish, Carassius auratus. Ethanol was administered to 10 to 15 g fish by mixing it in the water of a temperature gradient. The dose response curve was very steep between 0.5% (v/v) ethanol (no response) and 0.7% (significant lowering of selected temperature in treated fish). Fish were exposed to concentrations of ethanol as high as 1.7%, at which concentration most experimental fish lost their ability to swim upright in the water. At concentrations higher than 0.7%, the magnitude of the effect did not increase with increasing concentration of ethanol; treated animals continued to select temperatures about 2 C below temperatures selected by controls. Experiments alternating exposure to 1.0% ethanol and water showed that the rate of onset and disappearance of the ethanol effect was rapid (within 10 min). Other experiments exposing fish to 1.0% ethanol for up to 3 hr showed that the effect remained stable for this period of time. The thermoregulatory responses of fish are behavioral, and therefore relatively easy to observe and quantify. Ethanol produces a prompt, stable and reproducible depression of selected temperature in the goldfish. Because the temperature at which fish regulate is controlled by a central nervous system set point and not altered by effects on peripheral effector systems, it appears that ethanol may cause hypothermia in goldfish by directly acting to lower the set point. Close

• 83. [Article] Mindfulness and Test Performance after Stereotype Activation: a Randomized Experiment

  Although stereotype threat – pressure to avoid confirming or being judged based on a stereotype – has been found to affect performance on an array of tasks, few studies have examined ways to alleviate ...

  Citation × Citation Citation Abstract Copy Title: Mindfulness and Test Performance after Stereotype Activation: a Randomized Experiment Author: Daniel, Charles J.Z. Year: 2014 Although stereotype threat – pressure to avoid confirming or being judged based on a stereotype – has been found to affect performance on an array of tasks, few studies have examined ways to alleviate the threat after it has been activated. Previous research has demonstrated several outcomes of mindfulness exercises - increased emotional regulation, increased attentional regulation, change in perspective of self, and greater resources available to devote to learning – which parallel four potential mechanisms for stereotype threat: anxiety and SNS arousal, decreased working memory capacity, mindset, and effort. The present study tested the impact of two interventions - a 10-minute meditation practice and 10-minutes spent listening to relaxation music - on female math test performance in a stereotype threat situation. Participants were asked to indicate gender and the number of math courses they had taken in order to activate the "men are better than women at math" stereotype, then listened to music or meditation instructions for 10 minutes before filling taking a 20-item test consisting of sample GRE questions. After the test, a 17 item survey was administered in order to evaluate potential mediators. Results showed that (a) participants receiving the mindfulness intervention scored higher on the math test than participants who received no intervention after activation; and (b) participants receiving both the mindfulness and relaxation interventions reported putting forth greater effort on the math test than participants who received no intervention. Title: Mindfulness and Test Performance after Stereotype Activation: a Randomized Experiment Author: Daniel, Charles J.Z. Year: 2014 Although stereotype threat – pressure to avoid confirming or being judged based on a stereotype – has been found to affect performance on an array of tasks, few studies have examined ways to alleviate the threat after it has been activated. Previous research has demonstrated several outcomes of mindfulness exercises - increased emotional regulation, increased attentional regulation, change in perspective of self, and greater resources available to devote to learning – which parallel four potential mechanisms for stereotype threat: anxiety and SNS arousal, decreased working memory capacity, mindset, and effort. The present study tested the impact of two interventions - a 10-minute meditation practice and 10-minutes spent listening to relaxation music - on female math test performance in a stereotype threat situation. Participants were asked to indicate gender and the number of math courses they had taken in order to activate the "men are better than women at math" stereotype, then listened to music or meditation instructions for 10 minutes before filling taking a 20-item test consisting of sample GRE questions. After the test, a 17 item survey was administered in order to evaluate potential mediators. Results showed that (a) participants receiving the mindfulness intervention scored higher on the math test than participants who received no intervention after activation; and (b) participants receiving both the mindfulness and relaxation interventions reported putting forth greater effort on the math test than participants who received no intervention. Close

• 84. [Article] Waldo Lake Research in 2003

  This report summarizes the first year of an effort to develop a more complete understanding of the physical, chemical, and biological characteristics that drive the ecological processes of Waldo Lake. ...

  Citation × Citation Citation Abstract Copy Title: Waldo Lake Research in 2003 Author: Sytsma, Mark D., Rueter, John, Petersen, Richard, Koch, Roy, Wells, Scott A., Miller, Rich, Johnson, Laura, Annear, Robert Leslie Year: 2004 This report summarizes the first year of an effort to develop a more complete understanding of the physical, chemical, and biological characteristics that drive the ecological processes of Waldo Lake. Modern limnology recognizes the importance of watershed processes as well as in- lake processes in lake ecosystem functioning. Therefore, the approach included consideration of watershed hydrology and forcing functions that determine hydrodynamics of the system as well physical and chemical factors that may be important in regulating primary production in the lake. Data collected since 1998 was summarized and bathymetry of the basin was mapped using state-of-the-art digital depth sounding and GPS technology. A hypothesis that UV light may play an important role in regulating phytoplankton efficiency was examined in an effort to move toward more hypothesis-driven investigations to elucidate the factors controlling productivity. A Quality Assurance/Quality Control Plan was developed to guide data collection for long-term monitoring of the lake. Lastly, initial steps were made in the development of a model of lake hydrodynamics and primary production to aid in integration of the physical, chemical, and biological data that has been collected on the lake. Title: Waldo Lake Research in 2003 Author: Sytsma, Mark D., Rueter, John, Petersen, Richard, Koch, Roy, Wells, Scott A., Miller, Rich, Johnson, Laura, Annear, Robert Leslie Year: 2004 This report summarizes the first year of an effort to develop a more complete understanding of the physical, chemical, and biological characteristics that drive the ecological processes of Waldo Lake. Modern limnology recognizes the importance of watershed processes as well as in- lake processes in lake ecosystem functioning. Therefore, the approach included consideration of watershed hydrology and forcing functions that determine hydrodynamics of the system as well physical and chemical factors that may be important in regulating primary production in the lake. Data collected since 1998 was summarized and bathymetry of the basin was mapped using state-of-the-art digital depth sounding and GPS technology. A hypothesis that UV light may play an important role in regulating phytoplankton efficiency was examined in an effort to move toward more hypothesis-driven investigations to elucidate the factors controlling productivity. A Quality Assurance/Quality Control Plan was developed to guide data collection for long-term monitoring of the lake. Lastly, initial steps were made in the development of a model of lake hydrodynamics and primary production to aid in integration of the physical, chemical, and biological data that has been collected on the lake. Close

• 85. [Article] A Study of the U.S. Intrastate Crowdfunding Exemptions

  The enactment of intrastate crowdfunding exemptions around the United States has built up a lot of excitement. Crowdfunding became a popular phenomenon in the past 15 years for art and design projects. ...

  Citation × Citation Citation Abstract Copy Title: A Study of the U.S. Intrastate Crowdfunding Exemptions Author: Bohliqa, Ahmed Year: 2015 The enactment of intrastate crowdfunding exemptions around the United States has built up a lot of excitement. Crowdfunding became a popular phenomenon in the past 15 years for art and design projects. Crowdfunding companies only allowed raising money by receiving donations or loans without giving funders any security interests in the project's company. This is because any potential economic return could turn the transaction into a securities offering subject to the costly federal and state laws and regulations. Nonetheless, crowdfunding has been effective in enabling new innovations and ideas bloom. Intrastate securities crowdfunding might prove to be one of the most rewarding and game changing financial movements in the United States. It will strengthen the local economy represented by small businesses and help launch innovative new startups. However, its unique position between non-securities-based crowdfunding and private equity investments introduces complexity that must be mitigated before rewards can be harnesses. The paper analyzes this complexity by breaking it down into advantages and disadvantages. Each potential advantage and disadvantage is discussed and recommendations are made. Recommendations will be found useful for technology managers, technology entrepreneurs, organizations and agencies that plan to provide technical business services to entrepreneurs and small businesses, as well as advocates and regulators. Title: A Study of the U.S. Intrastate Crowdfunding Exemptions Author: Bohliqa, Ahmed Year: 2015 The enactment of intrastate crowdfunding exemptions around the United States has built up a lot of excitement. Crowdfunding became a popular phenomenon in the past 15 years for art and design projects. Crowdfunding companies only allowed raising money by receiving donations or loans without giving funders any security interests in the project's company. This is because any potential economic return could turn the transaction into a securities offering subject to the costly federal and state laws and regulations. Nonetheless, crowdfunding has been effective in enabling new innovations and ideas bloom. Intrastate securities crowdfunding might prove to be one of the most rewarding and game changing financial movements in the United States. It will strengthen the local economy represented by small businesses and help launch innovative new startups. However, its unique position between non-securities-based crowdfunding and private equity investments introduces complexity that must be mitigated before rewards can be harnesses. The paper analyzes this complexity by breaking it down into advantages and disadvantages. Each potential advantage and disadvantage is discussed and recommendations are made. Recommendations will be found useful for technology managers, technology entrepreneurs, organizations and agencies that plan to provide technical business services to entrepreneurs and small businesses, as well as advocates and regulators. Close

• 86. [Article] Neuropeptide Y: A potential Marker for a Life-History Transition in the Red-Sided Garter Snake (Thamnophis sirtalis)

  It is essential for organisms to exhibit appropriate behaviors as they transition from one life-history stage to another. While such life-history transitions are critical to both individual survival and ...

  Citation × Citation Citation Abstract Copy Title: Neuropeptide Y: A potential Marker for a Life-History Transition in the Red-Sided Garter Snake (Thamnophis sirtalis) Author: Richards, Daelyn Year: 2014 It is essential for organisms to exhibit appropriate behaviors as they transition from one life-history stage to another. While such life-history transitions are critical to both individual survival and reproductive fitness, we know very little about the underlying mechanisms. This project explores a potential mechanism regulating the transition of red-sided garter snakes (Thamnophis sirtalis) from reproductive to foraging behavior. After emerging from winter dormancy, male snakes engage in mate searching and mating behavior followed by a transition to foraging. Neuropeptide Y (NPY) is a neurohormone that controls appetite and feeding behavior in all organisms studied. We previously demonstrated that NPY cell number in the brain is increased in snakes exhibiting feeding behavior. In this study, we asked if brain NPY is involved in regulating the transition from courtship to foraging behavior under natural field conditions. To address this question, courting and foraging snakes were collected from the field and their behavioral preference confirmed by testing on a Y-maze. Snakes were then euthanized and the brains collected. An immunohistochemistry assay was performed for NPY; immunoreactive cells were counted manually. Quantification of NPY cell number in three different brain regions is currently being finalized (cortex, amygdala, and hypothalamus). We hypothesize that male snakes exhibiting feeding behavior will have more NPY cells than male snakes exhibiting mating behavior. If our hypothesis is supported, these data will provide evidence that NPY plays a role in mediating an important life-history transition between reproductive and feeding behaviors under natural field conditions. Title: Neuropeptide Y: A potential Marker for a Life-History Transition in the Red-Sided Garter Snake (Thamnophis sirtalis) Author: Richards, Daelyn Year: 2014 It is essential for organisms to exhibit appropriate behaviors as they transition from one life-history stage to another. While such life-history transitions are critical to both individual survival and reproductive fitness, we know very little about the underlying mechanisms. This project explores a potential mechanism regulating the transition of red-sided garter snakes (Thamnophis sirtalis) from reproductive to foraging behavior. After emerging from winter dormancy, male snakes engage in mate searching and mating behavior followed by a transition to foraging. Neuropeptide Y (NPY) is a neurohormone that controls appetite and feeding behavior in all organisms studied. We previously demonstrated that NPY cell number in the brain is increased in snakes exhibiting feeding behavior. In this study, we asked if brain NPY is involved in regulating the transition from courtship to foraging behavior under natural field conditions. To address this question, courting and foraging snakes were collected from the field and their behavioral preference confirmed by testing on a Y-maze. Snakes were then euthanized and the brains collected. An immunohistochemistry assay was performed for NPY; immunoreactive cells were counted manually. Quantification of NPY cell number in three different brain regions is currently being finalized (cortex, amygdala, and hypothalamus). We hypothesize that male snakes exhibiting feeding behavior will have more NPY cells than male snakes exhibiting mating behavior. If our hypothesis is supported, these data will provide evidence that NPY plays a role in mediating an important life-history transition between reproductive and feeding behaviors under natural field conditions. Close

• 87. [Article] Ecosystem Services as Boundary Objects for Transdisciplinary Collaboration

  The ecosystem services (ES) framework has potential to bring transdisciplinary teams together to achieve societal goals. Some label ES as “boundary objects” that help integrate diverse forms of knowledge ...

  Citation × Citation Citation Abstract Copy Title: Ecosystem Services as Boundary Objects for Transdisciplinary Collaboration Author: Steger, Cara, Hirsch, Shana, Evers, Cody, Branoff, Benjamin, Petrova, Maria, Nielsen-Pincus, Max, Wardropper, Chloe, van Riper, Carena J. Year: 2018 The ecosystem services (ES) framework has potential to bring transdisciplinary teams together to achieve societal goals. Some label ES as “boundary objects” that help integrate diverse forms of knowledge across social groups and organizational scales. However, this classification masks complexities that arise from unique characteristics of ES types (i.e., provisioning, regulating, and cultural), which influence their ability to function as boundary objects. We argue that interpretive flexibility and material structures interact in distinct ways across ES types throughout a boundary object “life cycle.” Viewing a 2015 U.S. federal memorandum as a catalyst, we critically evaluate the evolution of ES and its role as a boundary object. We propose that provisioning and regulating services are transitioning out of boundary object status, moving into a more standardized state. However, we anticipate that cultural services may continue to behave as boundary objects if collaborators maintain them as such. This shift in the functionality of ES as boundary objects is an important consideration for future research that attempts to reach across social worlds and disciplinary perspectives. We urge collaborations to rely on the most relevant disciplinary knowledge, rather than allowing the ease of standardized solutions to dictate the boundary of a given problem. Title: Ecosystem Services as Boundary Objects for Transdisciplinary Collaboration Author: Steger, Cara, Hirsch, Shana, Evers, Cody, Branoff, Benjamin, Petrova, Maria, Nielsen-Pincus, Max, Wardropper, Chloe, van Riper, Carena J. Year: 2018 The ecosystem services (ES) framework has potential to bring transdisciplinary teams together to achieve societal goals. Some label ES as “boundary objects” that help integrate diverse forms of knowledge across social groups and organizational scales. However, this classification masks complexities that arise from unique characteristics of ES types (i.e., provisioning, regulating, and cultural), which influence their ability to function as boundary objects. We argue that interpretive flexibility and material structures interact in distinct ways across ES types throughout a boundary object “life cycle.” Viewing a 2015 U.S. federal memorandum as a catalyst, we critically evaluate the evolution of ES and its role as a boundary object. We propose that provisioning and regulating services are transitioning out of boundary object status, moving into a more standardized state. However, we anticipate that cultural services may continue to behave as boundary objects if collaborators maintain them as such. This shift in the functionality of ES as boundary objects is an important consideration for future research that attempts to reach across social worlds and disciplinary perspectives. We urge collaborations to rely on the most relevant disciplinary knowledge, rather than allowing the ease of standardized solutions to dictate the boundary of a given problem. Close

• 88. [Article] Neoliberal and Neo-Communal Herring Fisheries in Southeast Alaska: Reframing Sustainability in Marine Ecosystems

  The transformation of Pacific herring (Clupea pallasii) fisheries from communal to commons to neoliberal regulation has had significant impacts on the health and sustainability of marine ecosystems on ...

  Citation × Citation Citation Abstract Copy Title: Neoliberal and Neo-Communal Herring Fisheries in Southeast Alaska: Reframing Sustainability in Marine Ecosystems Author: Thornton, Thomas F., Hebert, Jamie Year: 2015 The transformation of Pacific herring (Clupea pallasii) fisheries from communal to commons to neoliberal regulation has had significant impacts on the health and sustainability of marine ecosystems on the Northwest Coast of North America. Due to their abundance, seasonality, and sensitivity in disturbance, herring were carefully cultivated and protected by coastal Tlingit, Haida, and Tsimshian communities. The early industrial fishing era undermined this communalist approach in favor of an unregulated commons for bait and reduction fisheries, attracting non-local fleets and leading to conflicts with local Natives and tragedy of the commons style overexploitation of herring stocks by the mid-twentieth century. Since the 1970s, a re-regulated neoliberal sac roe fishery for Japanese markets has provided new opportunities for limited commercial permit holders, but with further depredations on local spawning populations. This paper uses frame theory and historical and political ecology to show how this transformation was justified by three critical but dubious (re)framings of Southeast herring populations under modern scientific management: (1) a reductionist framing of single species productivity models, expressed as herring “biomass,” within space and time (baseline scale framing); (2) the selective framing and privileging of human industrial predation under maximum sustainable yield (MSY) within a dynamic ecosystem of multiple predator populations (actor relations framing); and (3) the strategic framing of spawning failure events and policy responses to those events by professional fisheries managers (event–response framing). Finally, the paper argues for a new social–ecological systems approach, based on aboriginal models of herring cultivation, to sustain a commercial, subsistence, and restoration economy for the fishery. Title: Neoliberal and Neo-Communal Herring Fisheries in Southeast Alaska: Reframing Sustainability in Marine Ecosystems Author: Thornton, Thomas F., Hebert, Jamie Year: 2015 The transformation of Pacific herring (Clupea pallasii) fisheries from communal to commons to neoliberal regulation has had significant impacts on the health and sustainability of marine ecosystems on the Northwest Coast of North America. Due to their abundance, seasonality, and sensitivity in disturbance, herring were carefully cultivated and protected by coastal Tlingit, Haida, and Tsimshian communities. The early industrial fishing era undermined this communalist approach in favor of an unregulated commons for bait and reduction fisheries, attracting non-local fleets and leading to conflicts with local Natives and tragedy of the commons style overexploitation of herring stocks by the mid-twentieth century. Since the 1970s, a re-regulated neoliberal sac roe fishery for Japanese markets has provided new opportunities for limited commercial permit holders, but with further depredations on local spawning populations. This paper uses frame theory and historical and political ecology to show how this transformation was justified by three critical but dubious (re)framings of Southeast herring populations under modern scientific management: (1) a reductionist framing of single species productivity models, expressed as herring “biomass,” within space and time (baseline scale framing); (2) the selective framing and privileging of human industrial predation under maximum sustainable yield (MSY) within a dynamic ecosystem of multiple predator populations (actor relations framing); and (3) the strategic framing of spawning failure events and policy responses to those events by professional fisheries managers (event–response framing). Finally, the paper argues for a new social–ecological systems approach, based on aboriginal models of herring cultivation, to sustain a commercial, subsistence, and restoration economy for the fishery. Close

• 89. [Article] Mitochondria-derived Small Non-coding RNAs in Extreme Anoxia Tolerance

  Mitochondria are critical sensors of oxygen and play a major role in the regulation of the cellular response to oxygen deprivation. Understanding mitochondrial function during transitions into and out ...

  Citation × Citation Citation Abstract Copy Title: Mitochondria-derived Small Non-coding RNAs in Extreme Anoxia Tolerance Author: Riggs, Claire L., Podrabsky, Jason E. Year: 2017 Mitochondria are critical sensors of oxygen and play a major role in the regulation of the cellular response to oxygen deprivation. Understanding mitochondrial function during transitions into and out of anoxia in species that can tolerate anoxia may lend new insights into the role that mitochondria play in cellular homeostasis in response to fluctuating levels of oxygen. The objective of this study was to examine the potential role of small RNAs in long-term vertebrate anoxia tolerance. Expression patterns of small RNAs were determined using RNAseq in the most anoxia tolerant vertebrate, embryos of the annual killifishAustrofundulus limnaeus. Anoxia tolerance varies during development in this species in a way that allows for the comparison of developmental stages with extreme anoxia tolerance to stages with a more typical vertebrate anoxia tolerance. Embryos of 4 different developmental stages were exposed to anoxia, followed by aerobic recovery, and small RNA expression was determined with Illumina RNAseq under aerobic conditions, anoxia, and during aerobic recovery. A large proportion of the differentially expressed small RNAs were found to be encoded in the mitochondrial genome. About 12% of the unique small RNAs identified were encoded within the mitochondrial genome, and around 20% of the highly differentially expressed RNAs in response to anoxia were mitochondrial in origin. Of the differentially expressed sequences mapping to the mitochondrial genome, small RNAs derived from mitochondrial tRNAs were particularly enriched, with sequences up-regulated during anoxia and aerobic recovery from anoxia. These small RNAs of interest localize to anoxia sensitive tissues, such as the brain and heart, providing further evidence for a potential role in supporting anoxia tolerance. These same small RNAs have been detected in cell cultures derived from A. limnaeus embryos, by RNAseq and in situ hybridization. Cell culture expression patterns corroborated whole-embryo sequence expression patterns. This work highlights a potential new class of small RNAs derived from the mitochondrial genome that may act to mediate and coordinate the physiological response to anoxia in this species. Further understanding the biology of these mitochondrially-derived small RNAs and their role in anoxia tolerance may provide novel insight into combating cellular damage induced by heart attack and stroke, two lethal consequences of heart disease in humans. Title: Mitochondria-derived Small Non-coding RNAs in Extreme Anoxia Tolerance Author: Riggs, Claire L., Podrabsky, Jason E. Year: 2017 Mitochondria are critical sensors of oxygen and play a major role in the regulation of the cellular response to oxygen deprivation. Understanding mitochondrial function during transitions into and out of anoxia in species that can tolerate anoxia may lend new insights into the role that mitochondria play in cellular homeostasis in response to fluctuating levels of oxygen. The objective of this study was to examine the potential role of small RNAs in long-term vertebrate anoxia tolerance. Expression patterns of small RNAs were determined using RNAseq in the most anoxia tolerant vertebrate, embryos of the annual killifishAustrofundulus limnaeus. Anoxia tolerance varies during development in this species in a way that allows for the comparison of developmental stages with extreme anoxia tolerance to stages with a more typical vertebrate anoxia tolerance. Embryos of 4 different developmental stages were exposed to anoxia, followed by aerobic recovery, and small RNA expression was determined with Illumina RNAseq under aerobic conditions, anoxia, and during aerobic recovery. A large proportion of the differentially expressed small RNAs were found to be encoded in the mitochondrial genome. About 12% of the unique small RNAs identified were encoded within the mitochondrial genome, and around 20% of the highly differentially expressed RNAs in response to anoxia were mitochondrial in origin. Of the differentially expressed sequences mapping to the mitochondrial genome, small RNAs derived from mitochondrial tRNAs were particularly enriched, with sequences up-regulated during anoxia and aerobic recovery from anoxia. These small RNAs of interest localize to anoxia sensitive tissues, such as the brain and heart, providing further evidence for a potential role in supporting anoxia tolerance. These same small RNAs have been detected in cell cultures derived from A. limnaeus embryos, by RNAseq and in situ hybridization. Cell culture expression patterns corroborated whole-embryo sequence expression patterns. This work highlights a potential new class of small RNAs derived from the mitochondrial genome that may act to mediate and coordinate the physiological response to anoxia in this species. Further understanding the biology of these mitochondrially-derived small RNAs and their role in anoxia tolerance may provide novel insight into combating cellular damage induced by heart attack and stroke, two lethal consequences of heart disease in humans. Close

• 90. [Article] A Metabolic Hypothesis for the Evolution of Temperature Effects on the Arterial PCO2 and pH of Vertebrate Ectotherms

  Body temperature increases in ectothermic vertebrates characteristically lead to both increases in arterial PCO2 (PaCO2) and declines in resting arterial pH (pHa) of about 0.017 pH units/°C increase in ...

  Citation × Citation Citation Abstract Copy Title: A Metabolic Hypothesis for the Evolution of Temperature Effects on the Arterial PCO2 and pH of Vertebrate Ectotherms Author: Hillman, Stanley S., Hedrick, Michael Scott Year: 2017 Body temperature increases in ectothermic vertebrates characteristically lead to both increases in arterial PCO2 (PaCO2) and declines in resting arterial pH (pHa) of about 0.017 pH units/°C increase in temperature. This ‘alphastat’ pH pattern has previously been interpreted as being evolutionarily-driven by the maintenance of a constant protonation state on the imidazole moiety of histidine protein residues, hence stabilizing protein structure-function. Analysis of the existing data for interclass responses of ectothermic vertebrates show different degrees of PaCO2 increases and pH declines with temperature between the classes with reptiles>amphibians>fish. The PaCO2 at the temperature where maximal aerobic metabolism (VO2max) is achieved is significantly and positively correlated with temperature for all vertebrate classes. For ectotherms, the PaCO2 where VO2max is greatest is also correlated with VO2max indicating there is an increased driving force for CO2 efflux that is lowest in fish, intermediate in amphibians and highest in reptiles. The pattern of increased PaCO2 and the resultant reduction of pHa to increased body temperature would serve to increase CO2 efflux, O2 delivery, blood buffering capacity and maintain ventilatory scope. This represents a new hypothesis for the selective advantage of arterial pH regulation from a systems physiology perspective in addition to the advantages of maintenance of protein structure-function. Title: A Metabolic Hypothesis for the Evolution of Temperature Effects on the Arterial PCO2 and pH of Vertebrate Ectotherms Author: Hillman, Stanley S., Hedrick, Michael Scott Year: 2017 Body temperature increases in ectothermic vertebrates characteristically lead to both increases in arterial PCO2 (PaCO2) and declines in resting arterial pH (pHa) of about 0.017 pH units/°C increase in temperature. This ‘alphastat’ pH pattern has previously been interpreted as being evolutionarily-driven by the maintenance of a constant protonation state on the imidazole moiety of histidine protein residues, hence stabilizing protein structure-function. Analysis of the existing data for interclass responses of ectothermic vertebrates show different degrees of PaCO2 increases and pH declines with temperature between the classes with reptiles>amphibians>fish. The PaCO2 at the temperature where maximal aerobic metabolism (VO2max) is achieved is significantly and positively correlated with temperature for all vertebrate classes. For ectotherms, the PaCO2 where VO2max is greatest is also correlated with VO2max indicating there is an increased driving force for CO2 efflux that is lowest in fish, intermediate in amphibians and highest in reptiles. The pattern of increased PaCO2 and the resultant reduction of pHa to increased body temperature would serve to increase CO2 efflux, O2 delivery, blood buffering capacity and maintain ventilatory scope. This represents a new hypothesis for the selective advantage of arterial pH regulation from a systems physiology perspective in addition to the advantages of maintenance of protein structure-function. Close