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Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Selecting Surrogate Endpoints For Estimating Pesticide Effects On Avian Reproductive Success, Richard S. Bennett, Matthew A. Etterson
Selecting Surrogate Endpoints For Estimating Pesticide Effects On Avian Reproductive Success, Richard S. Bennett, Matthew A. Etterson
United States Environmental Protection Agency: Staff Publications
A Markov chain nest productivity model (MCnest) has been developed for projecting the effects of a specific pesticide‐use scenario on the annual reproductive success of avian species of concern. A critical element in MCnest is the use of surrogate endpoints, defined as measured endpoints from avian toxicity tests that represent specific types of effects possible in field populations at specific phases of a nesting attempt. In this article, we discuss the attributes of surrogate endpoints and provide guidance for selecting surrogates from existing avian laboratory tests as well as other possible sources.We also discuss some of the assumptions and uncertainties …
Exposure And Effects Of Perfluoroalkyl Substances In Tree Swallows Nesting In Minnesota And Wisconsin, Usa, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Matthew A. Etterson, Wayne E. Thogmartin, Qian Wu, Kurunthachalam Kannan, Annette Trowbridge, Patrick C. Mckann
Exposure And Effects Of Perfluoroalkyl Substances In Tree Swallows Nesting In Minnesota And Wisconsin, Usa, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Matthew A. Etterson, Wayne E. Thogmartin, Qian Wu, Kurunthachalam Kannan, Annette Trowbridge, Patrick C. Mckann
United States Environmental Protection Agency: Staff Publications
The exposure and effects of perfluoroalkyl substances (PFASs) were studied at eight locations in Minnesota and Wisconsin between 2007 and 2011 using tree swallows (Tachycineta bicolor). Concentrations of PFASs were quantified as were reproductive success end points. The sample egg method was used wherein an egg sample is collected, and the hatching success of the remaining eggs in the nest is assessed. The association between PFAS exposure and reproductive success was assessed by site comparisons, logistic regression analysis, and multistate modeling, a technique not previously used in this context. There was a negative association between concentrations of perfluorooctane …
Molecular Detection Of Campylobacter Spp. And Fecal Indicator Bacteria During The Northern Migration Of Sandhill Cranes (Grus Canadensis) At The Central Platte River, Jingrang Lu, Hodon Ryu, Jason R. Vogel, Jorge Santo Domingo, Nicholas J. Ashbolt
Molecular Detection Of Campylobacter Spp. And Fecal Indicator Bacteria During The Northern Migration Of Sandhill Cranes (Grus Canadensis) At The Central Platte River, Jingrang Lu, Hodon Ryu, Jason R. Vogel, Jorge Santo Domingo, Nicholas J. Ashbolt
United States Environmental Protection Agency: Staff Publications
The risk to human health of the annual sandhill crane (Grus canadensis) migration through Nebraska, which is thought to be a major source of fecal pollution of the central Platte River, is unknown. To better understand potential risks, the presence of Campylobacter species and three fecal indicator bacterial groups (Enterococcus spp., Escherichia coli, and Bacteroidetes) was assayed by PCR from crane excreta and water samples collected during their stopover at the Platte River, Nebraska, in 2010. Genus-specific PCR assays and sequence analyses identified Campylobacter jejuni as the predominant Campylobacter species in sandhill crane excreta. Campylobacter …
Quantifying The Effects Of Pesticide Exposure On Annual Reproductive Success Of Birds, Matthew A. Etterson, Richard S. Bennett
Quantifying The Effects Of Pesticide Exposure On Annual Reproductive Success Of Birds, Matthew A. Etterson, Richard S. Bennett
United States Environmental Protection Agency: Staff Publications
The Markov chain nest productivity model (MCnest) was developed for quantifying the effects of specific pesticide‐use scenarios on the annual reproductive success of simulated populations of birds. Each nesting attempt is divided into a series of discrete phases (e.g., egg laying, incubation, nestling rearing), and results from avian toxicity tests are used to represent the types of effects possible in the field during each breeding phase. The expected exposure dose each day throughout the breeding season can be compared to the toxicity thresholds assigned to each breeding phase to determine whether the nest attempt is at risk. The primary output …
Hidden Markov Models For Estimating Animal Mortality From Anthropogenic Hazards, Matthew A. Etterson
Hidden Markov Models For Estimating Animal Mortality From Anthropogenic Hazards, Matthew A. Etterson
United States Environmental Protection Agency: Staff Publications
Carcass searches are a common method for studying the risk of anthropogenic hazards to wildlife, including nontarget poisoning and collisions with anthropogenic structures. Typically, numbers of carcasses found must be corrected for scavenging rates and imperfect detection. Parameters for these processes (scavenging and detection) are often estimated using carcass distribution trials in which researchers place carcasses in the field at known times and locations. In this manuscript I develop a variety of estimators based on multi-event or hidden Markov models for use under different experimental conditions. I apply the estimators to two case studies of avian mortality, one from pesticide …
Comparison Of Pcr And Quantitative Real-Time Pcr Methods For The Characterization Of Ruminant And Cattle Fecal Pollution Sources, Meredith R. Raith, Catherine A. Kelty, John F. Griffith, Alexander Schriewer, Stefan Wuertz, Sophie Mieszkin, Michele Gourmelon, Georg H. Reischer, Andreas H. Farnleitner, Jared S. Ervin, Patricia A. Holden, Darcy L. Ebentier, Jennifer A. Jay, Dan Wang, Alexandria B. Boehm, Tiong Gim Aw, Joan B. Rose, E. Balleste, W.G. Meijer, Mano Sivaganesan, Orin C. Shanks
Comparison Of Pcr And Quantitative Real-Time Pcr Methods For The Characterization Of Ruminant And Cattle Fecal Pollution Sources, Meredith R. Raith, Catherine A. Kelty, John F. Griffith, Alexander Schriewer, Stefan Wuertz, Sophie Mieszkin, Michele Gourmelon, Georg H. Reischer, Andreas H. Farnleitner, Jared S. Ervin, Patricia A. Holden, Darcy L. Ebentier, Jennifer A. Jay, Dan Wang, Alexandria B. Boehm, Tiong Gim Aw, Joan B. Rose, E. Balleste, W.G. Meijer, Mano Sivaganesan, Orin C. Shanks
United States Environmental Protection Agency: Staff Publications
The State of California has mandated the preparation of a guidance document on the application of fecal source identification methods for recreational water quality management. California contains the fifth highest population of cattle in the United States, making the inclusion of cow-associated methods a logical choice. Because the performance of these methods has been shown to change based on geography and/or local animal feeding practices, laboratory comparisons are needed to determine which assays are best suited for implementation. We describe the performance characterization of two end-point PCR assays (CF128 and CF193) and five real-time quantitative PCR (qPCR) assays (Rum2Bac, BacR, …