The Experts below are selected from a list of 130173 Experts worldwide ranked by ideXlab platform
Gerald T Ankley - One of the best experts on this subject based on the ideXlab platform.
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assessment of status of white sucker catostomus commersoni Populations exposed to bleached kraft pulp mill effluent
Environmental Toxicology and Chemistry, 2013Co-Authors: David H Miller, Joseph E Tietge, Mark E Mcmaster, Kelly R Munkittrick, Xiangsheng Xia, Gerald T AnkleyAbstract:Credible ecological risk assessments often need to include analysis of Population-level impacts. In the present study, a predictive model was developed to investigate Population dynamics for white sucker (Catostomus commersoni) exposed to pulp mill effluent at a well-studied site in Jackfish Bay, Lake Superior, Canada. The model uniquely combines a Leslie Population projection matrix and the logistic equation to translate changes in the fecundity and the age structure of a breeding Population of white sucker exposed to pulp mill effluent to alterations in Population growth rate. Application of this density-dependent Population projection model requires construction of a life table for the organism of interest, a measure of carrying capacity, and an estimation of the effect of stressors on vital rates. A white sucker Population existing at carrying capacity and subsequently exposed to pulp mill effluent equivalent to a documented exposure experienced during the period 1988 to 1994 in Jackfish Bay would be expected to exhibit a 34% to 51% annual decrease in recruitment during the first 5 yr of exposure and approach a Population size of 71% of carrying capacity. The Jackfish Bay study site contains monitoring data for biochemical endpoints in white sucker, including circulating sex steroid concentrations, that could be combined with Population Modeling to utilize the model demonstrated at the Jackfish Bay study site for investigation of other white sucker Populations at sites that are less data-rich.
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assessment of status of white sucker catostomus commersoni Populations exposed to bleached kraft pulp mill effluent
Environmental Toxicology and Chemistry, 2013Co-Authors: David H Miller, Joseph E Tietge, Mark E Mcmaster, Kelly R Munkittrick, Xiangsheng Xia, Gerald T AnkleyAbstract:Credible ecological risk assessments often need to include analysis of Population-level impacts. In the present study, a predictive model was developed to investigate Population dynamics for white sucker (Catostomus commersoni) exposed to pulp mill effluent at a well-studied site in Jackfish Bay, Lake Superior, Canada. The model uniquely combines a Leslie Population projection matrix and the logistic equation to translate changes in the fecundity and the age structure of a breeding Population of white sucker exposed to pulp mill effluent to alterations in Population growth rate. Application of this density-dependent Population projection model requires construction of a life table for the organism of interest, a measure of carrying capacity, and an estimation of the effect of stressors on vital rates. A white sucker Population existing at carrying capacity and subsequently exposed to pulp mill effluent equivalent to a documented exposure experienced during the period 1988 to 1994 in Jackfish Bay would be expected to exhibit a 34% to 51% annual decrease in recruitment during the first 5 yr of exposure and approach a Population size of 71% of carrying capacity. The Jackfish Bay study site contains monitoring data for biochemical endpoints in white sucker, including circulating sex steroid concentrations, that could be combined with Population Modeling to utilize the model demonstrated at the Jackfish Bay study site for investigation of other white sucker Populations at sites that are less data-rich. Environ Toxicol Chem 2013;32:1592–1603. © 2013 SETAC
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adverse outcome pathways and ecological risk assessment bridging to Population level effects
Environmental Toxicology and Chemistry, 2011Co-Authors: Vincent J Kramer, Cheryl A. Murphy, Markus Hecker, Matthew A Etterson, Guritno Roesijadi, Daniel J Spade, Julann A Spromberg, Magnus Wang, Gerald T AnkleyAbstract:Maintaining the viability of Populations of plants and animals is a key focus for environmental regulation. Population-level responses integrate the cumulative effects of chemical stressors on individuals as those individuals interact with and are affected by their conspecifics, competitors, predators, prey, habitat, and other biotic and abiotic factors. Models of Population-level effects of contaminants can integrate information from lower levels of biological organization and feed that information into higher-level community and ecosystem models. As individual-level endpoints are used to predict Population responses, this requires that biological responses at lower levels of organization be translated into a form that is usable by the Population modeler. In the current study, we describe how mechanistic data, as captured in adverse outcome pathways (AOPs), can be translated into Modeling focused on Population-level risk assessments. First, we describe the regulatory context surrounding Population Modeling, risk assessment and the emerging role of AOPs. Then we present a succinct overview of different approaches to Population Modeling and discuss the types of data needed for these models. We describe how different key biological processes measured at the level of the individual serve as the linkage, or bridge, between AOPs and predictions of Population status, including consideration of community-level interactions and genetic adaptation. Several case examples illustrate the potential for use of AOPs in Population Modeling and predictive ecotoxicology. Finally, we make recommendations for focusing toxicity studies to produce the quantitative data needed to define AOPs and to facilitate their incorporation into Population Modeling. Environ. Toxicol. Chem. 2011;30:64–76. © 2010 SETAC
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adverse outcome pathways and ecological risk assessment bridging to Population level effects
Environmental Toxicology and Chemistry, 2011Co-Authors: Vincent J Kramer, Cheryl A. Murphy, Markus Hecker, Matthew A Etterson, Guritno Roesijadi, Daniel J Spade, Julann A Spromberg, Magnus Wang, Gerald T AnkleyAbstract:Maintaining the viability of Populations of plants and animals is a key focus for environmental regulation. Population-level responses integrate the cumulative effects of chemical stressors on individuals as those individuals interact with and are affected by their conspecifics, competitors, predators, prey, habitat, and other biotic and abiotic factors. Models of Population-level effects of contaminants can integrate information from lower levels of biological organization and feed that information into higher-level community and ecosystem models. As individual-level endpoints are used to predict Population responses, this requires that biological responses at lower levels of organization be translated into a form that is usable by the Population modeler. In the current study, we describe how mechanistic data, as captured in adverse outcome pathways (AOPs), can be translated into Modeling focused on Population-level risk assessments. First, we describe the regulatory context surrounding Population Modeling, risk assessment and the emerging role of AOPs. Then we present a succinct overview of different approaches to Population Modeling and discuss the types of data needed for these models. We describe how different key biological processes measured at the level of the individual serve as the linkage, or bridge, between AOPs and predictions of Population status, including consideration of community-level interactions and genetic adaptation. Several case examples illustrate the potential for use of AOPs in Population Modeling and predictive ecotoxicology. Finally, we make recommendations for focusing toxicity studies to produce the quantitative data needed to define AOPs and to facilitate their incorporation into Population Modeling.
Steven Russell - One of the best experts on this subject based on the ideXlab platform.
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a crispr cas9 gene drive system targeting female reproduction in the malaria mosquito vector anopheles gambiae
Nature Biotechnology, 2016Co-Authors: Andrew Hammond, Roberto Galizi, Kyros Kyrou, Alekos Simoni, Carla Siniscalchi, Dimitris Katsanos, Matthew Gribble, Dean A Baker, Eric Marois, Steven RussellAbstract:Development of a CRISPR/Cas9-based gene drive system in Anopheles gambiae, the main vector for the malaria parasite, paves the way for control of this pest insect. Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect Populations over a timeframe of a few years. We describe CRISPR-Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female-sterility phenotype upon disruption, and inserted into each locus CRISPR-Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6%. Population Modeling and cage experiments indicate that a CRISPR-Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect Population. These findings could expedite the development of gene drives to suppress mosquito Populations to levels that do not support malaria transmission.
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a crispr cas9 gene drive system targeting female reproduction in the malaria mosquito vector anopheles gambiae
Nature Biotechnology, 2016Co-Authors: Andrew Hammond, Roberto Galizi, Kyros Kyrou, Alekos Simoni, Carla Siniscalchi, Dimitris Katsanos, Matthew Gribble, Dean A Baker, Eric Marois, Steven RussellAbstract:Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect Populations over a timeframe of a few years. We describe CRISPR-Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female-sterility phenotype upon disruption, and inserted into each locus CRISPR-Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6%. Population Modeling and cage experiments indicate that a CRISPR-Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect Population. These findings could expedite the development of gene drives to suppress mosquito Populations to levels that do not support malaria transmission.
David H Miller - One of the best experts on this subject based on the ideXlab platform.
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assessment of status of white sucker catostomus commersoni Populations exposed to bleached kraft pulp mill effluent
Environmental Toxicology and Chemistry, 2013Co-Authors: David H Miller, Joseph E Tietge, Mark E Mcmaster, Kelly R Munkittrick, Xiangsheng Xia, Gerald T AnkleyAbstract:Credible ecological risk assessments often need to include analysis of Population-level impacts. In the present study, a predictive model was developed to investigate Population dynamics for white sucker (Catostomus commersoni) exposed to pulp mill effluent at a well-studied site in Jackfish Bay, Lake Superior, Canada. The model uniquely combines a Leslie Population projection matrix and the logistic equation to translate changes in the fecundity and the age structure of a breeding Population of white sucker exposed to pulp mill effluent to alterations in Population growth rate. Application of this density-dependent Population projection model requires construction of a life table for the organism of interest, a measure of carrying capacity, and an estimation of the effect of stressors on vital rates. A white sucker Population existing at carrying capacity and subsequently exposed to pulp mill effluent equivalent to a documented exposure experienced during the period 1988 to 1994 in Jackfish Bay would be expected to exhibit a 34% to 51% annual decrease in recruitment during the first 5 yr of exposure and approach a Population size of 71% of carrying capacity. The Jackfish Bay study site contains monitoring data for biochemical endpoints in white sucker, including circulating sex steroid concentrations, that could be combined with Population Modeling to utilize the model demonstrated at the Jackfish Bay study site for investigation of other white sucker Populations at sites that are less data-rich. Environ Toxicol Chem 2013;32:1592–1603. © 2013 SETAC
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assessment of status of white sucker catostomus commersoni Populations exposed to bleached kraft pulp mill effluent
Environmental Toxicology and Chemistry, 2013Co-Authors: David H Miller, Joseph E Tietge, Mark E Mcmaster, Kelly R Munkittrick, Xiangsheng Xia, Gerald T AnkleyAbstract:Credible ecological risk assessments often need to include analysis of Population-level impacts. In the present study, a predictive model was developed to investigate Population dynamics for white sucker (Catostomus commersoni) exposed to pulp mill effluent at a well-studied site in Jackfish Bay, Lake Superior, Canada. The model uniquely combines a Leslie Population projection matrix and the logistic equation to translate changes in the fecundity and the age structure of a breeding Population of white sucker exposed to pulp mill effluent to alterations in Population growth rate. Application of this density-dependent Population projection model requires construction of a life table for the organism of interest, a measure of carrying capacity, and an estimation of the effect of stressors on vital rates. A white sucker Population existing at carrying capacity and subsequently exposed to pulp mill effluent equivalent to a documented exposure experienced during the period 1988 to 1994 in Jackfish Bay would be expected to exhibit a 34% to 51% annual decrease in recruitment during the first 5 yr of exposure and approach a Population size of 71% of carrying capacity. The Jackfish Bay study site contains monitoring data for biochemical endpoints in white sucker, including circulating sex steroid concentrations, that could be combined with Population Modeling to utilize the model demonstrated at the Jackfish Bay study site for investigation of other white sucker Populations at sites that are less data-rich.
Richard M Sibly - One of the best experts on this subject based on the ideXlab platform.
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adding value to ecological risk assessment with Population Modeling
Human and Ecological Risk Assessment, 2011Co-Authors: Valery E. Forbes, P Calow, Volker Grimm, Takehiko I Hayashi, Tjalling Jager, Agnete Krabbe Katholm, Annemette Palmqvist, Rob Pastorok, Dan Salvito, Richard M SiblyAbstract:Current measures used to estimate the risks of toxic chemicals are not relevant to the goals of the environmental protection process, and thus ecological risk assessment (ERA) is not used as extensively as it should be as a basis for cost-effective management of environmental resources. Appropriate Population models can provide a powerful basis for expressing ecological risks that better inform the environmental management process and thus that are more likely to be used by managers. Here we provide at least five reasons why Population Modeling should play an important role in bridging the gap between what we measure and what we want to protect. We then describe six actions needed for its implementation into management-relevant ERA.
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the extrapolation problem and how Population Modeling can help
Environmental Toxicology and Chemistry, 2008Co-Authors: Valery E. Forbes, P Calow, Richard M SiblyAbstract:We argue that Population Modeling can add value to ecological risk assessment by reducing uncertainty when extrapolating from ecotoxicological observations to relevant ecological effects. We review other methods of extrapolation, ranging from application factors to species sensitivity distributions to suborganismal (biomarker and "-omics") responses to quantitative structure-activity relationships and model ecosystems, drawing attention to the limitations of each. We suggest a simple classification of Population models and critically examine each model in an extrapolation context. We conclude that Population models have the potential for adding value to ecological risk assessment by incorporating better understanding of the links between individual responses and Population size and structure and by incorporating greater levels of ecological complexity. A number of issues, however, need to be addressed before such models are likely to become more widely used. In a science context, these involve challenges in parameterization, questions about appropriate levels of complexity, issues concerning how specific or general the models need to be, and the extent to which interactions through competition and trophic relationships can be easily incorporated.
Andrew Hammond - One of the best experts on this subject based on the ideXlab platform.
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a crispr cas9 gene drive system targeting female reproduction in the malaria mosquito vector anopheles gambiae
Nature Biotechnology, 2016Co-Authors: Andrew Hammond, Roberto Galizi, Kyros Kyrou, Alekos Simoni, Carla Siniscalchi, Dimitris Katsanos, Matthew Gribble, Dean A Baker, Eric Marois, Steven RussellAbstract:Development of a CRISPR/Cas9-based gene drive system in Anopheles gambiae, the main vector for the malaria parasite, paves the way for control of this pest insect. Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect Populations over a timeframe of a few years. We describe CRISPR-Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female-sterility phenotype upon disruption, and inserted into each locus CRISPR-Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6%. Population Modeling and cage experiments indicate that a CRISPR-Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect Population. These findings could expedite the development of gene drives to suppress mosquito Populations to levels that do not support malaria transmission.
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a crispr cas9 gene drive system targeting female reproduction in the malaria mosquito vector anopheles gambiae
Nature Biotechnology, 2016Co-Authors: Andrew Hammond, Roberto Galizi, Kyros Kyrou, Alekos Simoni, Carla Siniscalchi, Dimitris Katsanos, Matthew Gribble, Dean A Baker, Eric Marois, Steven RussellAbstract:Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect Populations over a timeframe of a few years. We describe CRISPR-Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female-sterility phenotype upon disruption, and inserted into each locus CRISPR-Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6%. Population Modeling and cage experiments indicate that a CRISPR-Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect Population. These findings could expedite the development of gene drives to suppress mosquito Populations to levels that do not support malaria transmission.