The Experts below are selected from a list of 267 Experts worldwide ranked by ideXlab platform

Daniel Schlenk - One of the best experts on this subject based on the ideXlab platform.

  • annual and seasonal evaluation of reproductive status in hornyhead turbot at municipal wastewater outfalls in the southern california bight
    Environmental Toxicology and Chemistry, 2012
    Co-Authors: Kristy L Forsgren, Steven M Bay, Doris E Vidaldorsch, Xin Deng, Jeff Armstrong, Joseph R Gully, Daniel Schlenk
    Abstract:

    Treated wastewater effluent containing endocrine-disrupting chemicals is discharged into the coastal waters of the Southern California Bight (SCB) daily. The present study investigated changes in indicators of reproductive health and environmental estrogen exposure in hornyhead turbot (Pleuronichthys verticalis) near wastewater outfalls. Fish were collected from discharge areas, farfield stations, and a Reference Location in the SCB to examine spatial and temporal patterns. Fish from the Orange County outfall farfield site were younger and less sexually mature than fish from other sites. The sex ratio was skewed in some fish from outfall sites as well as from the Dana Point Reference site. However, no consistent pattern in sex ratio was present over time. Low-level induction of vitellogenin was frequently observed in male fish from all sites, suggesting widespread exposure to estrogenic compounds, but did not appear to impact reproductive function as there was no incidence of gonad abnormalities (ova-testis). Analysis of historical hornyhead turbot trawl data indicated that populations are either increasing or stable in the SCB; thus, environmental estrogen exposure was not adversely impacting fish abundance. Additional research is needed to determine the cause of the estrogenic response in hornyhead turbot and whether the source of the estrogenic compounds is a consequence of historical contamination or of ongoing sources or representative of baseline characteristic of this species. Environ. Toxicol. Chem. 2012; 31: 2701–2710. © 2012 SETAC

  • Site-specific effects of 17β-estradiol in hornyhead turbot (Pleuronichthys verticalis) collected from a wastewater outfall and Reference Location
    Environmental research, 2009
    Co-Authors: Mary Ann Rempel-hester, Xin Deng, Jeff Armstrong, Joseph R Gully, Haizheng Hong, Yinsheng Wang, Daniel Schlenk
    Abstract:

    Abstract Studies throughout the southern California bight have indicated persistent estrogenic activity in male hornyhead turbot (Pleuronichthys verticalis). Plasma 17β-estradiol (E2) concentrations correlated with gonadal DNA damage in fish collected near a wastewater treatment plant outfall, but not from fish collected at the Reference Location. When the same species was collected from the same Reference Location and treated with E2, no relationship between uptake and gonadal DNA damage was observed. To evaluate the site-specific effects of E2 in fish from a wastewater outfall and fish from a Reference Location, male hornyhead turbot from each Location were exposed to 15 μg/L aqueous E2 in a time-course experiment, with fish sampled every 12 h for 48 h. Concentrations of E2 were measured in the aqueous exposure and in plasma from the fish. Vitellogenin (vtg) was also measured in the plasma, and 8-oxo-7,8-dihydro-2′-deoxyguanosine levels in male gonads were measured as an indicator of DNA damage. Untreated fish from the outfall had significantly lower E2 in the plasma relative to the untreated Reference fish, and this trend was consistent at each time point in the E2-treated fish. Vtg was significantly induced after 36 h of exposure in fish from both sites and no significant differences were observed between the sites. A significant increase of oxidative DNA damage was observed in E2-treated fish from the outfall population and the damage was significantly correlated with plasma E2 concentrations only in fish from the outfall after 48 h. These results indicated that there were significant differences in E2 disposition and gonadal genotoxicity between the hornyhead turbot populations following exposure to E2, suggesting that fish at wastewater outfalls may be more sensitive to DNA damage, which may be temporally related to concentrations of E2 in plasma.

Rajesh Vasa - One of the best experts on this subject based on the ideXlab platform.

  • SIGSPATIAL/GIS - Spatio-Temporal Reference Frames as Geographic Objects
    Proceedings of the 25th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 2017
    Co-Authors: Andrew J. Simmons, Rajesh Vasa
    Abstract:

    It is often desirable to analyse trajectory data in local coordinates relative to a Reference Location. Similarly, temporal data also needs to be transformed to be relative to an event. Together, temporal and spatial contextualisation permits comparative analysis of similar trajectories taken across multiple Reference Locations. To the GIS professional, the procedures to establish a Reference frame at a Location and reproject the data into local coordinates are well known, albeit tedious. However, GIS tools are now often used by subject matter experts who may not have the deep knowledge of coordinate frames and projections required to use these techniques effectively. We introduce a novel method for representing spatio-temporal Reference frames using ordinary geographic objects available in GIS tools. We argue that our method both reduces the number of manual steps required to reproject data to a local Reference frame, in addition to reducing the number of concepts a novice user would need to learn.

  • Spatio-Temporal Reference Frames as Geographic Objects
    arXiv: Human-Computer Interaction, 2017
    Co-Authors: Andrew J. Simmons, Rajesh Vasa
    Abstract:

    It is often desirable to analyse trajectory data in local coordinates relative to a Reference Location. Similarly, temporal data also needs to be transformed to be relative to an event. Together, temporal and spatial contextualisation permits comparative analysis of similar trajectories taken across multiple Reference Locations. To the GIS professional, the procedures to establish a Reference frame at a Location and reproject the data into local coordinates are well known, albeit tedious. However, GIS tools are now often used by subject matter experts who may not have the deep knowledge of coordinate frames and projections required to use these techniques effectively. We introduce a novel method for representing spatio-temporal Reference frames using ordinary geographic objects available in GIS tools. We argue that our method both reduces the number of manual steps required to reproject data to a local Reference frame, in addition to reducing the number of concepts a novice user would need to learn.

Andrew J. Simmons - One of the best experts on this subject based on the ideXlab platform.

  • SIGSPATIAL/GIS - Spatio-Temporal Reference Frames as Geographic Objects
    Proceedings of the 25th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems, 2017
    Co-Authors: Andrew J. Simmons, Rajesh Vasa
    Abstract:

    It is often desirable to analyse trajectory data in local coordinates relative to a Reference Location. Similarly, temporal data also needs to be transformed to be relative to an event. Together, temporal and spatial contextualisation permits comparative analysis of similar trajectories taken across multiple Reference Locations. To the GIS professional, the procedures to establish a Reference frame at a Location and reproject the data into local coordinates are well known, albeit tedious. However, GIS tools are now often used by subject matter experts who may not have the deep knowledge of coordinate frames and projections required to use these techniques effectively. We introduce a novel method for representing spatio-temporal Reference frames using ordinary geographic objects available in GIS tools. We argue that our method both reduces the number of manual steps required to reproject data to a local Reference frame, in addition to reducing the number of concepts a novice user would need to learn.

  • Spatio-Temporal Reference Frames as Geographic Objects
    arXiv: Human-Computer Interaction, 2017
    Co-Authors: Andrew J. Simmons, Rajesh Vasa
    Abstract:

    It is often desirable to analyse trajectory data in local coordinates relative to a Reference Location. Similarly, temporal data also needs to be transformed to be relative to an event. Together, temporal and spatial contextualisation permits comparative analysis of similar trajectories taken across multiple Reference Locations. To the GIS professional, the procedures to establish a Reference frame at a Location and reproject the data into local coordinates are well known, albeit tedious. However, GIS tools are now often used by subject matter experts who may not have the deep knowledge of coordinate frames and projections required to use these techniques effectively. We introduce a novel method for representing spatio-temporal Reference frames using ordinary geographic objects available in GIS tools. We argue that our method both reduces the number of manual steps required to reproject data to a local Reference frame, in addition to reducing the number of concepts a novice user would need to learn.

Joseph R Gully - One of the best experts on this subject based on the ideXlab platform.

  • annual and seasonal evaluation of reproductive status in hornyhead turbot at municipal wastewater outfalls in the southern california bight
    Environmental Toxicology and Chemistry, 2012
    Co-Authors: Kristy L Forsgren, Steven M Bay, Doris E Vidaldorsch, Xin Deng, Jeff Armstrong, Joseph R Gully, Daniel Schlenk
    Abstract:

    Treated wastewater effluent containing endocrine-disrupting chemicals is discharged into the coastal waters of the Southern California Bight (SCB) daily. The present study investigated changes in indicators of reproductive health and environmental estrogen exposure in hornyhead turbot (Pleuronichthys verticalis) near wastewater outfalls. Fish were collected from discharge areas, farfield stations, and a Reference Location in the SCB to examine spatial and temporal patterns. Fish from the Orange County outfall farfield site were younger and less sexually mature than fish from other sites. The sex ratio was skewed in some fish from outfall sites as well as from the Dana Point Reference site. However, no consistent pattern in sex ratio was present over time. Low-level induction of vitellogenin was frequently observed in male fish from all sites, suggesting widespread exposure to estrogenic compounds, but did not appear to impact reproductive function as there was no incidence of gonad abnormalities (ova-testis). Analysis of historical hornyhead turbot trawl data indicated that populations are either increasing or stable in the SCB; thus, environmental estrogen exposure was not adversely impacting fish abundance. Additional research is needed to determine the cause of the estrogenic response in hornyhead turbot and whether the source of the estrogenic compounds is a consequence of historical contamination or of ongoing sources or representative of baseline characteristic of this species. Environ. Toxicol. Chem. 2012; 31: 2701–2710. © 2012 SETAC

  • Site-specific effects of 17β-estradiol in hornyhead turbot (Pleuronichthys verticalis) collected from a wastewater outfall and Reference Location
    Environmental research, 2009
    Co-Authors: Mary Ann Rempel-hester, Xin Deng, Jeff Armstrong, Joseph R Gully, Haizheng Hong, Yinsheng Wang, Daniel Schlenk
    Abstract:

    Abstract Studies throughout the southern California bight have indicated persistent estrogenic activity in male hornyhead turbot (Pleuronichthys verticalis). Plasma 17β-estradiol (E2) concentrations correlated with gonadal DNA damage in fish collected near a wastewater treatment plant outfall, but not from fish collected at the Reference Location. When the same species was collected from the same Reference Location and treated with E2, no relationship between uptake and gonadal DNA damage was observed. To evaluate the site-specific effects of E2 in fish from a wastewater outfall and fish from a Reference Location, male hornyhead turbot from each Location were exposed to 15 μg/L aqueous E2 in a time-course experiment, with fish sampled every 12 h for 48 h. Concentrations of E2 were measured in the aqueous exposure and in plasma from the fish. Vitellogenin (vtg) was also measured in the plasma, and 8-oxo-7,8-dihydro-2′-deoxyguanosine levels in male gonads were measured as an indicator of DNA damage. Untreated fish from the outfall had significantly lower E2 in the plasma relative to the untreated Reference fish, and this trend was consistent at each time point in the E2-treated fish. Vtg was significantly induced after 36 h of exposure in fish from both sites and no significant differences were observed between the sites. A significant increase of oxidative DNA damage was observed in E2-treated fish from the outfall population and the damage was significantly correlated with plasma E2 concentrations only in fish from the outfall after 48 h. These results indicated that there were significant differences in E2 disposition and gonadal genotoxicity between the hornyhead turbot populations following exposure to E2, suggesting that fish at wastewater outfalls may be more sensitive to DNA damage, which may be temporally related to concentrations of E2 in plasma.

Jeff Armstrong - One of the best experts on this subject based on the ideXlab platform.

  • annual and seasonal evaluation of reproductive status in hornyhead turbot at municipal wastewater outfalls in the southern california bight
    Environmental Toxicology and Chemistry, 2012
    Co-Authors: Kristy L Forsgren, Steven M Bay, Doris E Vidaldorsch, Xin Deng, Jeff Armstrong, Joseph R Gully, Daniel Schlenk
    Abstract:

    Treated wastewater effluent containing endocrine-disrupting chemicals is discharged into the coastal waters of the Southern California Bight (SCB) daily. The present study investigated changes in indicators of reproductive health and environmental estrogen exposure in hornyhead turbot (Pleuronichthys verticalis) near wastewater outfalls. Fish were collected from discharge areas, farfield stations, and a Reference Location in the SCB to examine spatial and temporal patterns. Fish from the Orange County outfall farfield site were younger and less sexually mature than fish from other sites. The sex ratio was skewed in some fish from outfall sites as well as from the Dana Point Reference site. However, no consistent pattern in sex ratio was present over time. Low-level induction of vitellogenin was frequently observed in male fish from all sites, suggesting widespread exposure to estrogenic compounds, but did not appear to impact reproductive function as there was no incidence of gonad abnormalities (ova-testis). Analysis of historical hornyhead turbot trawl data indicated that populations are either increasing or stable in the SCB; thus, environmental estrogen exposure was not adversely impacting fish abundance. Additional research is needed to determine the cause of the estrogenic response in hornyhead turbot and whether the source of the estrogenic compounds is a consequence of historical contamination or of ongoing sources or representative of baseline characteristic of this species. Environ. Toxicol. Chem. 2012; 31: 2701–2710. © 2012 SETAC

  • Site-specific effects of 17β-estradiol in hornyhead turbot (Pleuronichthys verticalis) collected from a wastewater outfall and Reference Location
    Environmental research, 2009
    Co-Authors: Mary Ann Rempel-hester, Xin Deng, Jeff Armstrong, Joseph R Gully, Haizheng Hong, Yinsheng Wang, Daniel Schlenk
    Abstract:

    Abstract Studies throughout the southern California bight have indicated persistent estrogenic activity in male hornyhead turbot (Pleuronichthys verticalis). Plasma 17β-estradiol (E2) concentrations correlated with gonadal DNA damage in fish collected near a wastewater treatment plant outfall, but not from fish collected at the Reference Location. When the same species was collected from the same Reference Location and treated with E2, no relationship between uptake and gonadal DNA damage was observed. To evaluate the site-specific effects of E2 in fish from a wastewater outfall and fish from a Reference Location, male hornyhead turbot from each Location were exposed to 15 μg/L aqueous E2 in a time-course experiment, with fish sampled every 12 h for 48 h. Concentrations of E2 were measured in the aqueous exposure and in plasma from the fish. Vitellogenin (vtg) was also measured in the plasma, and 8-oxo-7,8-dihydro-2′-deoxyguanosine levels in male gonads were measured as an indicator of DNA damage. Untreated fish from the outfall had significantly lower E2 in the plasma relative to the untreated Reference fish, and this trend was consistent at each time point in the E2-treated fish. Vtg was significantly induced after 36 h of exposure in fish from both sites and no significant differences were observed between the sites. A significant increase of oxidative DNA damage was observed in E2-treated fish from the outfall population and the damage was significantly correlated with plasma E2 concentrations only in fish from the outfall after 48 h. These results indicated that there were significant differences in E2 disposition and gonadal genotoxicity between the hornyhead turbot populations following exposure to E2, suggesting that fish at wastewater outfalls may be more sensitive to DNA damage, which may be temporally related to concentrations of E2 in plasma.