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1.
J Environ Manage ; 358: 120702, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631165

RESUMO

Wildfires are increasing in duration and intensity across the United States' Pacific West region, resulting in heightened particulate matter from smoke in the atmosphere. Levels of peak particulate matter are concurrent to peak visitor attendance at National Parks, given seasonal alignment with summer vacation travel and heightened forest fire conditions. Particulate matter threatens visitor health and safety and contributes to poor visibility and a deteriorated visitor experience. To assess visitation response to diminished air quality, we utilized wildfire-generated particulate matter (PM2.5) data in conjunction with monthly attendance records for three ecoregions containing eight national parks in Washington, Oregon, and California from 2009 to 2019. We analyzed daily PM2.5 levels from data gridded at the 10 km scale for National Park Service units by Level III forest ecoregions within the National Park Service's Pacific West Unit. Data were then compared to normalized monthly visitation trends for each of the ecoregions using two statistical methods Kendall's Tau and Analysis of Variance (ANOVA) with post-hoc Tukey tests. Results demonstrate that attendance at these national parks does not decrease in response to increased PM2.5 levels. Instead, we see several statistically significant increases in attendance across these ecoregions during periods of reduced air quality. Of 115 shifts between air quality categories during the busy season of July to September, there are no significant decreases in attendance as air quality worsens. These findings suggest that visitors are willing to tolerate reduced air quality compared to other factors such as temperature or precipitation. Given that park units within each ecoregion feature diverse historical contexts, varied built environments, and unique ecological systems, our discussion specifically addresses managerial concerns associated with maintained high levels of visitation during suboptimal, and potentially dangerous, conditions. There is substantial need for specific, scalable approaches to mitigate adverse health and experiential impacts as visitors are exposed to increased risks during a range of exertional activities associated with diverse settings.


Assuntos
Poluição do Ar , Material Particulado , Estações do Ano , Poluição do Ar/análise , Material Particulado/análise , Oregon , Florestas , Parques Recreativos , Incêndios Florestais , California , Washington , Humanos , Monitoramento Ambiental
2.
J Environ Manage ; 357: 120699, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552516

RESUMO

The US National Park System encompasses diverse environmental and tourism management regimes, together governed by the 1916 Organic Act and its dual mandate of conservation and provision of public enjoyment. However, with the introduction of transformative science policy in the 2000's, the mission scope has since expanded to promote overarching science-based objectives. Yet despite this paradigm shift instituting "science for parks, parks for science", there is scant research exploring the impact of the National Park Science Policy on the provision of knowledge. We address this gap by developing a spatiotemporal framework for evaluating research alignment, here operationalized via quantifiable measures of supply and demand for scientific knowledge. Specifically, we apply a machine learning algorithm (Latent Dirichlet analysis) to a comprehensive park-specific text corpus (combining official needs statements -i.e. demand- and scientific research metadata -i.e. supply-) to define a joint topic space, which thereby facilitates quantifying the direction and degree of alignment at multiple levels. Results indicate an overall robust degree of research alignment, with misaligned topics tending to be over-researched (as opposed to over-demanded), which may be favorable to many parks, but is inefficient from the park system perspective. Results further indicate that the transformative science policy exacerbated the misalignment in mandated research domains. In light of these results, we argue for improved decision support mechanisms to achieve more timely alignment of research efforts towards distinctive park needs, thereby fostering convergent knowledge co-production and leveraging the full value of National Parks as living laboratories.


Assuntos
Conservação dos Recursos Naturais , Parques Recreativos , Conservação dos Recursos Naturais/métodos , Políticas
3.
Environ Manage ; 73(6): 1215-1229, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38578324

RESUMO

As representative of the water-energy-food nexus, fossil fuel development and industrial agriculture are rural industries that continue to expand and increasingly occur in the same areas. Being a top agricultural export county and the fossil fuel capital of California while ranking among the worst in the US for industrial pollution, Kern County is a poster child of rural nexus development and, thus, an essential place for initiating sustainability transitions. Such transitions rely on policy support and the adoption of methods by individuals and communities who may disagree with such changes. While sense of place and impact perceptions are recognized as playing critical roles in sustainability management, they have yet to be utilized in nexus research. A survey (N = 256) of the perceived impacts of nexus industries with place meaning and place attachment as possible drivers for perceptions was conducted in nexus industry pollution exposure risk zones. Factor analysis and bivariate correlations showed that place meaning and place attachment are drivers for perceptions while also being drivers for concern for changes in nexus industries. While perceptions of impacts indicated contested place meanings, participants strongly perceive the economy and environment as being in decline. To build support for sustainability policy, directing funds from Kern County's renewable energy industry to local sectors of society, implementation of regenerative agriculture, cooperative management, and nurturing place meaning as aligned with nature's restorative quality are important paths forward. These nexus management foci could strengthen place attachment, build trust in government, and repair environmental alienation.


Assuntos
Agricultura , Conservação dos Recursos Naturais , California , Humanos , População Rural , Combustíveis Fósseis
5.
Neuroimage ; 132: 439-454, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26931817

RESUMO

In this work, we propose DR-TAMAS (Diffeomorphic Registration for Tensor Accurate alignMent of Anatomical Structures), a novel framework for intersubject registration of Diffusion Tensor Imaging (DTI) data sets. This framework is optimized for brain data and its main goal is to achieve an accurate alignment of all brain structures, including white matter (WM), gray matter (GM), and spaces containing cerebrospinal fluid (CSF). Currently most DTI-based spatial normalization algorithms emphasize alignment of anisotropic structures. While some diffusion-derived metrics, such as diffusion anisotropy and tensor eigenvector orientation, are highly informative for proper alignment of WM, other tensor metrics such as the trace or mean diffusivity (MD) are fundamental for a proper alignment of GM and CSF boundaries. Moreover, it is desirable to include information from structural MRI data, e.g., T1-weighted or T2-weighted images, which are usually available together with the diffusion data. The fundamental property of DR-TAMAS is to achieve global anatomical accuracy by incorporating in its cost function the most informative metrics locally. Another important feature of DR-TAMAS is a symmetric time-varying velocity-based transformation model, which enables it to account for potentially large anatomical variability in healthy subjects and patients. The performance of DR-TAMAS is evaluated with several data sets and compared with other widely-used diffeomorphic image registration techniques employing both full tensor information and/or DTI-derived scalar maps. Our results show that the proposed method has excellent overall performance in the entire brain, while being equivalent to the best existing methods in WM.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Algoritmos , Anisotropia , Substância Cinzenta/anatomia & histologia , Humanos , Processamento de Imagem Assistida por Computador , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Substância Branca/anatomia & histologia
6.
Am J Phys Med Rehabil ; 103(6): 561-565, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363773

RESUMO

ABSTRACT: Residency recruitment practices have undergone significant changes in the last several years. Interviews are now conducted fully virtually leading to both positive and negative downstream effects, including decreased cost to applicants and programs, decreased time away from clinical activities, flexibility in scheduling, and increased applications for applicants and program directors. In response to these changes, the Association of Academic Physiatrists Residency and Fellowship Program Directors Council convened a workgroup consisting of program directors, program coordinators, residents, and medical students who reviewed the available literature to provide an evidence-based set of best practices for program leaders and applicants. Available data from the Association of American Medical Colleges and its relevance to future recruitment cycles are also discussed.


Assuntos
Bolsas de Estudo , Internato e Residência , Seleção de Pessoal , Medicina Física e Reabilitação , Humanos , Estados Unidos , Medicina Física e Reabilitação/educação , Educação de Pós-Graduação em Medicina
7.
Sci Total Environ ; 819: 152955, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35007592

RESUMO

In the U.S. Pacific Northwest and California contaminants entering surface water may harm Endangered Species Act (ESA) listed salmonid species and consequently there is ongoing concern regarding agricultural practices and resulting pesticide surface water loading may adversely impact salmonid species, their food web, and habitat. Characterizing pesticide exposure in surface water at the watershed scale and beyond is challenging due to uncertainty regarding pesticide use practices and sparse monitoring data. We report here a 2-year continuous deployment of passive sampling devices (PSDs) for monitoring of pesticides in surface water at the outflow of the Zollner Creek watershed located within the Willamette Basin, Oregon, USA. This watershed is predominately agricultural and within the geographic range of two ESA listed Pacific salmonid species. Grab and passive sampling monitoring data were used to evaluate the performance of a probabilistic application of the Soil and Water Assessment Tool (SWAT), a physically based process model which integrates institutional and local knowledge and expertise to investigate the relationship between land use practices and pesticide surface water loading at the watershed scale. SWAT estimated pesticide surface water concentrations for the pesticides chlorpyrifos and trifluralin followed temporal trend in PSD monitoring results and the 5th to 95th percentile range of estimated pesticide concentrations based on the probabilistic assessment encompassed 65-76% of the observed PSD concentrations. Evaluation of model estimates for metolachlor in surface water was challenged by insufficient publicly available grab sample monitoring data. A process to estimate pesticide surface water concentrations on biologically relevant time scales and comparison to screening level aquatic life benchmarks is presented. Additionally, model estimates were used to characterize the variance in surface water concentrations in this small hydrologically responsive watershed to determine grab sampling frequency adequate for model evaluation.


Assuntos
Praguicidas , Poluentes Químicos da Água , Agricultura , Monitoramento Ambiental/métodos , Oregon , Praguicidas/análise , Água , Poluentes Químicos da Água/análise
8.
Environ Toxicol Chem ; 41(4): 1054-1065, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34964987

RESUMO

Chlorpyrifos, a broad-spectrum neurotoxic organophosphate insecticide, is subject to atmospheric and hydrolytic transport from application sites to aquatic ecosystems. Across the landscape, concentrations in surface water can vary spatially and temporally according to seasonal use practices. Standardized bioassays can provide a screening-level understanding of aquatic receptor acute and chronic toxicity. However, these bioassays do not address ecologically relevant exposure patterns that may impact fitness and survival within and across generations. The aim of the present study was to evaluate the utility of a second-tier, screening-level methodology employing Daphnia magna multi- and transgenerational bioassays spanning four generations to investigate the effect of variable chronic chlorpyrifos exposure. The multigenerational assay consisted of continuous chlorpyrifos exposure across four consecutive 21-day bioassays using progeny from the previous assay for each successive generation. In the transgenerational assay, only the parent (F0) generation was exposed. For both assays, survival and reproduction were assessed across treatments and generations. Results indicated that (1) following continuous chlorpyrifos exposure at ecologically relevant concentrations to four generations of D. magna, the highest treatment showed an apparent tolerance response for both survival and reproductive success in the F3 generation, and (2) chlorpyrifos exposure to the F0 generation did not result in treatment effects in the unexposed F1, F2, and F3 generations in the apical endpoints of survival and reproduction. Employing a suite of acute and chronic bioassays, including chronic exposures spanning multiple generations, allows for a more robust screening-level evaluation of the potential impact of chlorpyrifos on aquatic receptors for variable periods of exposure. Environ Toxicol Chem 2022;41:1054-1065. © 2021 SETAC.


Assuntos
Clorpirifos , Inseticidas , Poluentes Químicos da Água , Animais , Clorpirifos/toxicidade , Daphnia , Ecossistema , Inseticidas/toxicidade , Reprodução , Poluentes Químicos da Água/toxicidade
9.
PLoS One ; 17(11): e0276442, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36350919

RESUMO

Patients often provide untruthful information about their health to avoid embarrassment, evade treatment, or prevent financial loss. Privacy disclosures (e.g. HIPAA) intended to dissuade privacy concerns may actually increase patient lying. We used new mouse tracking-based technology to detect lies through mouse movement (distance and time to response) and patient answer adjustment in an online controlled study of 611 potential patients, randomly assigned to one of six treatments. Treatments differed in the notices patients received before health information was requested, including notices about privacy, benefits of truthful disclosure, and risks of inaccurate disclosure. Increased time or distance of device mouse movement and greater adjustment of answers indicate less truthfulness. Mouse tracking revealed a significant overall effect (p<0.001) by treatment on the time to reach their final choice. The control took the least time indicating greater truthfulness and the privacy + risk group took the longest indicating least truthfulness. Privacy, risk, and benefit disclosure statements led to greater lying. These differences were moderated by gender. Mouse tracking results largely confirmed the answer adjustment lie detection method with an overall treatment effect (p < .0001) and gender differences (p < .0001) on truthfulness. Privacy notices led to decreased patient honesty. Privacy notices should perhaps be administered well before personal health disclosure is requested to minimize patient untruthfulness. Mouse tracking and answer adjustment appear to be health care lie-detection methods to enhance optimal diagnosis and treatment.


Assuntos
Confidencialidade , Privacidade , Revelação , Coleta de Dados , Atenção à Saúde
10.
Chemosphere ; 276: 130120, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33706179

RESUMO

Chlorpyrifos (CPF) is a widely used broad-spectrum organophosphate insecticide. CPF elicits neurotoxic effects in exposed organisms by inhibiting the activity of acetylcholinesterase enzymes (AChE), which prolongs nerve transmission and results in neurotoxic symptoms and death at high doses. While CPF is capable of eliciting neurotoxic effects, chlorpyrifos-oxon (CPFO) is the primary neurotoxicant agent. Aquatic organisms bioactivate CPF to CPFO through the Cytochrome P450 phase I metabolic pathway following exposure to CPF. Additionally, in the environment, CPF transforms to CPFO, primarily through photo-oxidation. As both compounds can be transported in air and water to aquatic ecosystems, there is the potential for exposure to non-target organisms. The potential for adverse impacts on aquatic receptors depends on patterns of exposure and toxicity of individual compounds and the mixture. To study the neurotoxicity of these compounds, a 48 h acute and 21 d chronic Daphnia magna bioassay was conducted independently with CPF and CPFO. Acute bioassay results show a median lethal concentration (LC50) of 0.76 µg L-1 for CPF and 0.32 µg L-1 for CPFO, suggesting that CPFO is 2.4 times more acutely toxic to D. magna. Acute assay results were also used to derive Benchmark Dose Levels of 0.58 µg L-1 for CPF and 0.25 µg L-1 for CPFO. However, neither compound elicited an effect on reproduction or growth at relevant chronic exposures. As D. magna are a small and relatively sensitive species, and the AChE inhibition adverse outcome pathway is highly conserved, these results may be cautiously extrapolated in assessing adverse impacts on aquatic receptors.1.


Assuntos
Clorpirifos , Inseticidas , Acetilcolinesterase , Animais , Clorpirifos/toxicidade , Daphnia , Ecossistema , Inseticidas/toxicidade
11.
Am J Phys Med Rehabil ; 100(2S Suppl 1): S45-S50, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33252467

RESUMO

ABSTRACT: In 2015, the Accreditation Council for Graduate Medical Education published the Physical Medicine and Rehabilitation Milestones 1.0 as part of the Next Accreditation System. This was the culmination of more than 20 yrs of work on the part of the Accreditation Council for Graduate Medical Education to improve graduate medical education competency assessments. The six core competencies were patient care, medical knowledge, systems-based practice, practice-based learning and improvement, professionalism, and interpersonal and communication skills. While providing a good foundation for resident assessment, the Physical Medicine and Rehabilitation Milestones 1.0 was not without faults. With input from program directors, national organizations, and the public, the Physical Medicine and Rehabilitation Milestones 2.0 strives to further advance resident assessment, providing improvements through the integration of the harmonized Milestones and the addition of a supplemental guide.


Assuntos
Acreditação/normas , Competência Clínica/normas , Educação Baseada em Competências/normas , Educação de Pós-Graduação em Medicina/normas , Internato e Residência/normas , Medicina Física e Reabilitação/educação , Atitude do Pessoal de Saúde , Humanos , Estados Unidos
12.
Front Psychol ; 11: 528079, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33364992

RESUMO

Computer users are often the last line of defense in computer security. However, with repeated exposures to system messages and computer security warnings, neural and behavioral responses show evidence of habituation. Habituation has been demonstrated at a neural level as repetition suppression where responses are attenuated with subsequent repetitions. In the brain, repetition suppression to visual stimuli has been demonstrated in multiple cortical areas, including the occipital lobe and medial temporal lobe. Prior research into the repetition suppression effect has generally focused on a single repetition and has not examined the pattern of signal suppression with repeated exposures. We used complex, everyday stimuli, in the form of images of computer programs or security warning messages, to examine the repetition suppression effect across repeated exposures. The use of computer warnings as stimuli also allowed us to examine the activation of learned fearful stimuli. We observed widespread linear decreases in activation with repeated exposures, suggesting that repetition suppression continues after the first repetition. Further, we found greater activation for warning messages compared to neutral images in the anterior insula, pre-supplemental motor area, and inferior frontal gyrus, suggesting differential processing of security warning messages. However, the repetition suppression effect was similar in these regions for both warning messages and neutral images. Additionally, we observed an increase of activation in the default mode network with repeated exposures, suggestive of increased mind wandering with continuing habituation.

13.
Environ Health ; 8: 18, 2009 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-19379510

RESUMO

BACKGROUND: Regulatory decisions to phase-out the availability and use of common organophosphate pesticides among the general public were announced in 2000 and continued through 2004. Based on revised risk assessments, chlorpyrifos and diazinon were determined to pose unacceptable risks. To determine the impact of these decisions, organophosphate (OP) exposure incidents reported to the National Pesticide Information Center (NPIC) were analyzed for longitudinal trends. METHODS: Non-occupational human exposure incidents reported to NPIC were grouped into pre- (1995-2000) and post-announcement periods (2001-2007). The number of total OP exposure incidents, as well as reports for chlorpyrifos, diazinon and malathion, were analyzed for significant differences between these two periods. The number of informational inquiries from the general public was analyzed over time as well. RESULTS: The number of average annual OP-related exposure incidents reported to NPIC decreased significantly between the pre- and post-announcement periods (p < 0.001). A significant decrease in the number of chlorpyrifos and diazinon reports was observed over time (p < 0.001). No significant difference in the number of incident reports for malathion was observed (p = 0.4), which was not phased-out of residential use. Similar to exposure incidents, the number of informational inquiries received by NPIC declined over time following the phase-out announcement. CONCLUSION: Consistent with other findings, the number of chlorpyrifos and diazinon exposure incidents reported to NPIC significantly decreased following public announcement and targeted regulatory action.


Assuntos
Exposição Ambiental/efeitos adversos , Fiscalização e Controle de Instalações , Regulamentação Governamental , Organofosfatos/efeitos adversos , Exposição Ambiental/análise , Humanos , Incidência , Estudos Longitudinais , Medição de Risco
14.
J Environ Qual ; 48(4): 1047-1056, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31589676

RESUMO

Nonpoint-source pollutant surface water loading from agricultural lands, including sediment, nutrients, and pesticides, is a major concern. As contaminants entering surface water may harm endangered species, there is ongoing concern regarding the compliance of agricultural practices with the Endangered Species Act (ESA). Compliance with the ESA for the protection of threatened salmonid species is of particular concern in the Pacific Northwest region of the United States. We report here use of the Soil and Water Assessment Tool (SWAT) to characterize ecohydrology and solute transport in the Zollner Creek watershed, Willamette River basin, Oregon. Using a systems approach, integrating institutional expertise with local knowledge, we evaluated a succession of parameterization scenarios designed to sufficiently simulate watershed ecohydrology. The model was further evaluated through simulation of solute transport. Using probabilistic methods to characterize pesticide application patterns, SWAT concurrent mean estimates of daily atrazine surface water concentrations were correlated with observed instantaneous grab samples ( = 0.37) and followed the general trend of the observed data near the watershed outlet. Further development of this modeling application may provide a new understanding of continuous pesticide surface water loading at the watershed scale, allowing assessment of environmental impacts with much greater certainty, thereby facilitating consideration of refined mitigation strategies.


Assuntos
Praguicidas , Poluentes Químicos da Água , Agricultura , Modelos Teóricos , Noroeste dos Estados Unidos , Análise de Sistemas , Estados Unidos
15.
Environ Toxicol Chem ; 27(2): 397-403, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18348627

RESUMO

Field-collected Brachycentrus americanus Banks (Trichoptera: Brachycentridae) larvae were used to investigate the relationship between esfenvalerate exposure and case-abandonment response, determine larval ability to construct a new case, and measure the change in predation risk to insects in rebuilt cases. We evaluated case-abandonment following four environmentally relevant esfenvalerate exposures, 0.05, 0.1, 0.2, and 0.4 microg/L; 48-h exposures to 0.2 and 0.4 microg/L (nominal) esfenvalerate both resulted in over 60% of larvae abandoning cases and were statistically indistinguishable. Propensity to engage in building behaviors was significantly diminished in 0.2 and 0.4 microg/L esfenvalerate-exposed insects that had abandoned cases, with less than 20% of exposed insects producing cases. Cases built by intoxicated larvae were characterized by a disorganized composition, and required half the pressure to crush versus cases built by nonexposed larvae. Pre-exposing case-building material to 1 microg/L esfenvalerate also reduced the physical strength of rebuilt cases. Larvae inhabiting weaker rebuilt cases and larvae without cases were significantly more susceptible to predation by second year Hesperoperla pacifica Banks (Plecoptera: Perlidae) stonefly nymphs than those in original cases. Overall, we concluded that small behavioral responses can have profound consequences for survival of species and reveal susceptible stages in life-cycles that can be overlooked by conventional approaches to ecological risk assessment.


Assuntos
Comportamento Animal/efeitos dos fármacos , Insetos/efeitos dos fármacos , Inseticidas/farmacologia , Nitrilas/farmacologia , Piretrinas/farmacologia , Animais , Bioensaio/métodos , Relação Dose-Resposta a Droga , Monitoramento Ambiental/métodos , Insetos/fisiologia , Larva/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia
16.
Environ Toxicol Chem ; 27(8): 1713-20, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18616380

RESUMO

We investigated Baetis spp. (mayfly), Hesperoperla pacifica (stonefly), and Brachycentrus americanus (caddisfly) susceptibility at the egg stage to esfenvalerate, a synthetic pyrethroid insecticide. Eggs were obtained from the field or from field-collected gravid females at sites near Corvallis (OR, USA) and the Metolius River at Camp Sherman (OR, USA) for static exposures under controlled conditions for temperature and light. Eggs were exposed to esfenvalerate for 48 h at concentrations ranging from 0.025 to 4.0 microg/L. No effect on mortality or posthatch growth was detected in H. pacifica eggs exposed to esfenvalerate concentrations up to 1.0 microg/L. Exposure to 0.07 microg/L of esfenvalerate, however, caused a significant increase in Baetis spp. egg mortality, and exposure of near-eclosion eggs to lower concentrations (0.025 and 0.05 microg/L) resulted in behavioral effects and reduced survivorship in newly hatched Baetis nymphs. Early stage B. americanus eggs were 10-fold more sensitive to esfenvalerate when removed from the gelatinous clutch before exposure, an indication that the gelatin affords protection from toxicant exposure. Exposures of near-hatch B. americanus clutches to esfenvalerate concentrations ranging between 0.035 and 0.2 microg/L, however, resulted in significant clutch death within clutches resulting from behavioral aberrations of first-instar larvae. The results of the present study suggest that aquatic insect egg clutch morphology can be a strong influence on susceptibility of embryos to esfenvalerate exposure.


Assuntos
Larva/efeitos dos fármacos , Nitrilas/toxicidade , Piretrinas/toxicidade , Animais , Bioensaio , Relação Dose-Resposta a Droga , Exposição Ambiental , Monitoramento Ambiental , Insetos , Inseticidas/toxicidade , Luz , Temperatura , Fatores de Tempo
17.
Environ Toxicol Chem ; 27(8): 1721-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18616382

RESUMO

Given the chemical properties of synthetic pyrethroids, it is probable that compounds, including esfenvalerate, that enter surface waters may become incorporated into aquatic insect food sources. We examined the effect of dietary esfenvalerate uptake in aquatic insects representing different functional feeding groups. We used three field-collected aquatic insect species: A grazing scraper, Cinygmula reticulata McDunnough (Ephemeroptera: Heptageniidae); an omnivorous filter feeder, Brachycentrus americanus Banks (Trichoptera: Brachycentridae); and a predator, Hesperoperla pacifica Banks (Plecoptera: Perlidae). Laboratory-cultured algae were preexposed for 24 h to esfenvalerate concentrations of 0, 0.025, 0.05, and 0.1 microg/L and provided to two C. reticulata age classes (small and final-instar nymphs). Reduction in small nymph growth was observed following three weeks of feeding on algae exposed to 0.05 and 0.1 microg/L of esfenvalerate, and the highest dietary exposure reduced egg production in final-instar nymphs. The diet for B. americanus and H. pacifica consisted of dead third-instar Chironomus tentans larvae preexposed for 24 h to esfenvalerate concentrations ranging between 0.1 and 1.0 microg/L. Consumption of larvae exposed to 0.5 to 1.0 microg/L of esfenvalerate caused case abandonment and mortality in B. americanus caddisfly larvae. Although H. pacifica nymphs readily consumed esfenvalerate-exposed larvae, no adverse effects were observed during the present study. Furthermore, no evidence of esfenvalerate-induced feeding deterrence was found in any of the species tested, suggesting that aquatic insects may not be able to distinguish between pyrethroid-contaminated and uncontaminated food sources. These findings indicate that feeding deterrence is not a factor in regulating aquatic insect dietary exposures to synthetic pyrethroids.


Assuntos
Larva/efeitos dos fármacos , Nitrilas/toxicidade , Ninfa/efeitos dos fármacos , Piretrinas/toxicidade , Poluentes Químicos da Água/farmacologia , Ração Animal , Animais , Comportamento Animal , Dieta , Relação Dose-Resposta a Droga , Comportamento Alimentar , Insetos , Inseticidas/toxicidade , Especificidade da Espécie
18.
Environ Toxicol Chem ; 27(8): 1728-34, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18616381

RESUMO

We investigated the impact of aquatic insect life stage and emergence strategy on sensitivity to esfenvalerate, a synthetic pyrethroid insecticide, using field-collected Brachycentrus americanus Banks (Trichoptera: Brachycentridae) and Cinygmula reticulata McDunnough (Ephemeroptera: Heptageniidae) insects. Final-instar C. reticulata emergence was observed for one week following three environmentally relevant, 48-h esfenvalerate exposures (0.005, 0.01, and 0.015 microg/L). Emergence was significantly depressed following exposure to esfenvalerate and resulted from an increase in nymph mortality during the emergence process. This experiment was duplicated for late-instar C. reticulata nymphs, which were similar in size to the final-instar nymphs but were not near emergence. Late-instar C. reticulata mayflies were approximately fivefold less sensitive to esfenvalerate exposures as gauged by one-week mortality rates. Brachycentrus americanus pupal mortality was significantly increased over that in controls following 48-h esfenvalerate exposures of 0.1 and 0.2 microg/L. These response concentrations correlated closely with those for case-abandonment rates of fourth-instar B. americanus larvae (a sublethal effect of esfenvalerate exposure). Pupal mortality rates were approximately 16-fold higher than those observed in larvae. Adult female egg weight as a percentage of total body weight was significantly decreased following pupal esfenvalerate exposures of 0.05, 0.1, and 0.2 microg/L. These findings suggest that exposure to esfenvalerate may impair hemimetabolous insect emergence behaviors and may decrease fecundity in holometabolous aquatic insects.


Assuntos
Larva/efeitos dos fármacos , Nitrilas/toxicidade , Ninfa/efeitos dos fármacos , Piretrinas/toxicidade , Poluentes Químicos da Água/farmacologia , Animais , Bioensaio , Tamanho Corporal , Peso Corporal , Dieta , Relação Dose-Resposta a Droga , Feminino , Insetos , Inseticidas/toxicidade , Fatores de Tempo
19.
Environ Toxicol Chem ; 26(4): 732-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17447558

RESUMO

Growth, reproductive ability, and metabolic functions may be impaired by disruption of early endocrine patterning. Natural and synthetic estrogens detected in surface waters have been linked to reproductive endocrine signaling disruption in several species. The present study characterizes the nonreproductive morphological endpoint of vertebral anomalies in fish exposed to environmental estrogens. Estrogen is a proliferation-inducing compound in osteoblasts, regulating cartilage and bone deposition during development in vertebrates. The hypothesis for the present work is that xenobiotics with estrogenic activity adversely impact vertebral bone formation. Fathead minnows (Pimephales promelas) were exposed to 0.1 to 100 microg/L 17alpha-ethinylestradiol (EE2) and 0.1 to 1,000 microg/L bisphenol A (BPA) from egg stage (24 h postfertilization) to 25 to 26 d posthatch. Fish were measured for length and analyzed microscopically to determine degree of skeletal development (developmental score) and the occurrence of spinal abnormalities, including vertebral compression, bone fusion, and spinal curvatures. Fish length and developmental score were inversely related to vertebral malformations in exposed fish. Skeletal developmental was affected significantly in EE2-exposed fish: Vertebral malformations were observed in up to 62% of fish in a nonmonotonic dose-response. However, BPA did not significantly impair skeletal development or induce vertebral malformations. The bioassay results suggest vertebral bone development is a potential endpoint of endocrine disruption from potent estrogenic compounds in surface waters.


Assuntos
Cyprinidae/fisiologia , Exposição Ambiental , Poluentes Ambientais/toxicidade , Estradiol/toxicidade , Osteogênese/efeitos dos fármacos , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/crescimento & desenvolvimento , Animais , Pesos e Medidas Corporais , Relação Dose-Resposta a Droga , Radiografia , Coluna Vertebral/diagnóstico por imagem
20.
Vet Clin North Am Exot Anim Pract ; 19(2): 501-12, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27131161

RESUMO

Successful care of the critical pet bird patient is dependent on preparation and planning and begins with the veterinarian and hospital staff. An understanding of avian physiology and pathophysiology is key. Physical preparation of the hospital or clinic includes proper equipment and understanding of the procedures necessary to provide therapeutic and supportive care to the avian patient. An overview of patient intake and assessment, intensive care environment, and fluid therapy is included.


Assuntos
Animais Exóticos , Doenças das Aves/diagnóstico , Emergências/veterinária , Animais , Doenças das Aves/terapia , Aves , Cuidados Críticos , Exame Físico/veterinária , Medicina Veterinária
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