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The habitat amount hypothesis (HAH) stresses the importance of total patch amount over the size of individual patches in determining species richness within a local landscape. However, the absence of some species from patches too small to contain a territory would be inconsistent with the HAH. Using the association of territory size with body size and the circle as optimal territory shape, we tested several HAH predictions of threshold patch occupancy and richness of 19 guilds of primarily insectivorous breeding birds. We characterized 16 guild-associated patch types at high spatial resolution and assigned one type to each guild. We measured functional patch size as the largest circle that fit within each patch type occurring in a local landscape. Functional patch size was the sole or primary predictor in regression models of species richness for 15 of the 19 guilds. Total patch amount was the sole or primary variable in only 2 models. Quantifying patch size at high resolution also demonstrated that breeding birds should be absent from patches that are too small to contain a territory and larger species should occur only in larger patches. Functional patch size is a readily interpretable metric that helps explain the habitat basis for differences in species composition and richness between areas. It provides a tool to assess the combined effects of patch size, shape and perforation on threshold habitat availability, and with total patch amount can inform design and/or evaluation of conservation, restoration or enhancement options for focal taxa or biodiversity in general.
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Biodiversidad , Ecosistema , Animales , AvesRESUMEN
Microplastic pollution is measured with a variety of sampling methods. Field experiments indicate that commonly used sampling methods, including net, pump, and grab samples, do not always result in equivalent measured concentration. We investigate the comparability of these methods through a meta-analysis of 121 surface water microplastic studies. We find systematic relationships between measured concentration and sampled volume, method of collection, mesh size used for filtration, and waterbody sampled. Most significantly, a strong log-linear relationship exists between sample volume and measured concentration, with small-volume grab samples measuring up to 104 particles/L higher concentrations than larger volume net samples, even when sampled concurrently. Potential biasing factors explored included filtration size (±102 particles/L), net volume overestimation (±101 particles/L), fiber loss through net mesh (unknown magnitude), intersample variability (±101 particles/L), and contamination, the potential factor with an effect large enough (±103 particles/L) to explain the observed differences. On the basis of these results, we caution against comparing concentrations across multiple studies or combining multiple study results to identify regional patterns. Additionally, we emphasize the importance of contamination reduction and quantification strategies, namely that blank samples from all stages of field sampling be collected and reported as a matter of course for all studies.
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Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Contaminación Ambiental , Plásticos , Contaminantes Químicos del Agua/análisisAsunto(s)
Investigación Biomédica , Neoplasias , Humanos , Neoplasias/terapia , Niño , Investigadores , Defensa del Paciente , Conducta CooperativaRESUMEN
This paper provides a response to Hanna Pickard and Stephen Pearce's paper 'Balancing costs and benefits: a clinical perspective does not support a harm minimisation approach for self-injury outside of community settings.' This paper responded to my article 'Should healthcare professionals sometimes allow harm? The case of self-injury.' There is much in the paper that I would agree with, but I feel it is important to respond to a number of the criticisms of my paper in order to clarify my position and to facilitate ongoing debate in relation to this important issue.
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Autonomía Personal , Conducta Autodestructiva , Reducción del Daño , Personal de Salud , Humanos , PaternalismoRESUMEN
A 30-year-old bald eagle ( Haliaeetus leucocephalus) was presented with a history of hyporexia and lethargy. Results of initial hematologic testing, biochemical analysis, and fecal examination were unremarkable, and clinical signs did not resolve with supportive care and management changes. Results of echocardiography, based on auscultation of a murmur, and coelomic endoscopy, based on the presence of a soft tissue opacity on radiographs, as well as an aspergillosis panel were largely unsuccessful in determining a definitive diagnosis. Euthanasia was performed after the eagle did not recover from anesthesia after endoscopy. Necropsy results demonstrated bilateral testicular seminomas with metastases to the ventriculus. This case demonstrates an abnormal metastasis of a common reproductive tumor in an avian species.
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Enfermedades de las Aves/patología , Águilas , Neoplasias Cardíacas/veterinaria , Seminoma/veterinaria , Neoplasias Testiculares/veterinaria , Testículo/patología , Animales , Neoplasias Cardíacas/secundario , Masculino , Seminoma/patología , Neoplasias Testiculares/patologíaRESUMEN
This paper considers the ethical justification for the use of harm minimisation approaches with individuals who self-injure. While the general issues concerning harm minimisation have been widely debated, there has been only limited consideration of the ethical issues raised by allowing people to continue injuring themselves as part of an agreed therapeutic programme. I will argue that harm minimisation should be supported on the basis that it results in an overall reduction in harm when compared with more traditional ways of dealing with self-injurious behaviour. It will be argued that this is an example of a situation where healthcare professionals sometimes have a moral obligation to allow harm to come to their patients.
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Reducción del Daño/ética , Paternalismo/ética , Relaciones Médico-Paciente/ética , Conducta Autodestructiva/terapia , Actitud del Personal de Salud , Conducta de Ayuda , Humanos , Obligaciones Morales , Autonomía Personal , Conducta Autodestructiva/psicologíaRESUMEN
Macrorhabdus ornithogaster is a yeast organism that infects multiple species of captive and wild birds. Diagnosis of infection in vivo has proven difficult historically, as shedding can be intermittent, and not all positive animals are clinically ill. We compared polymerase chain reaction (PCR) of cloacal swab samples and fecal Gram's stain (FGS) for diagnosis of active shedding of M ornithogaster in a captive flock of budgerigars ( Melopsittacus undulatus ). Of the 100 birds sampled, 57 (57%) were positive for M ornithogaster by PCR and 24 (24%) were positive for M ornithogaster by FGS. All FGS-tested birds also were positive on PCR. There was a significant association between the two methods, but the overall percent agreement for the two methods was only 67%. Based on these findings, cloacal swab PCR is more likely to diagnose the presence of M ornithogaster than FGS in budgerigars.
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Enfermedades de las Aves/diagnóstico , Melopsittacus , Micosis/veterinaria , Levaduras/aislamiento & purificación , Animales , Cloaca/microbiología , Micosis/diagnóstico , Micosis/microbiologíaRESUMEN
Forest degradation is arguably the greatest threat to biodiversity, ecosystem services, and rural livelihoods. Therefore, increasing understanding of how organisms respond to degradation is essential for management and conservation planning. We were motivated by the need for rapid and practical analytical tools to assess the influence of management and degradation on biodiversity and system state in areas subject to rapid environmental change. We compared bird community composition and size in managed (ejido, i.e., communally owned lands) and unmanaged (national park) forests in the Sierra Tarahumara region, Mexico, using multispecies occupancy models and data from a 2-year breeding bird survey. Unmanaged sites had on average higher species occupancy and richness than managed sites. Most species were present in low numbers as indicated by lower values of detection and occupancy associated with logging-induced degradation. Less than 10% of species had occupancy probabilities >0.5, and degradation had no positive effects on occupancy. The estimated metacommunity size of 125 exceeded previous estimates for the region, and sites with mature trees and uneven-aged forest stand characteristics contained the highest species richness. Higher estimation uncertainty and decreases in richness and occupancy for all species, including habitat generalists, were associated with degraded young, even-aged stands. Our findings show that multispecies occupancy methods provide tractable measures of biodiversity and system state and valuable decision support for landholders and managers. These techniques can be used to rapidly address gaps in biodiversity information, threats to biodiversity, and vulnerabilities of species of interest on a landscape level, even in degraded or fast-changing environments. Moreover, such tools may be particularly relevant in the assessment of species richness and distribution in a wide array of habitats.
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Aves/fisiología , Conservación de los Recursos Naturales , Animales , Teorema de Bayes , Biodiversidad , Agricultura Forestal , México , Modelos Teóricos , Densidad de Población , Dinámica PoblacionalRESUMEN
Subjective risk perceptions give rise to unique policy implications as they reflect both the expectation of risk exposure and the ability to mitigate or cope with the adverse impacts. Based on data collected from semistructured interviews and iterative ranking exercises with 159 households in the Altay and Tianshan Mountains of Xinjiang, China, this study investigates and explains the risks with respect to a seriously understudied population and location. Using both geostatistical and econometric methods, we show that although fear of environmental crisis is prevalent among our respondents, recently implemented pastoral conservation, sedentarization, and development projects are more likely to be ranked as the top concerns among affected households. In order to reduce these concerns, future pastoral policy must be built on the livestock economy, and intervention priority should be given to the geographic areas identified as risk hot spots. In cases where pastoralists have to give up their pastures, the transition to other comparable livelihood strategies must be enabled by creating new opportunities and training pastoralists to acquire the needed skills.
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Crianza de Animales Domésticos , Salud Ambiental , Medición de Riesgo , Medio Social , Animales , China , HumanosRESUMEN
Copper-based aquatic algaecides have been widely used in the management of aquatic macrophyte and harmful algal blooms for decades due to their effectiveness and low cost. However, repeated treatment of freshwater lakes results in the accumulation of copper in the sediment, which may adversely affect the ecosystem of the lakes through toxicity to benthic invertebrates and other organisms. Consequently, copper-based aquatic herbicides and algaecides have been frequently subjected to regulations aimed at preventing further ecological deterioration in treated waterbodies. Many states in the US are taking or considering taking an approach that limits or prohibits copper treatment in waterbodies. Freshwater lakes with extensive historical copper treatments typically have significantly higher concentrations of copper in the sediment than untreated lakes. However, the correlation between the extent of the treatments and level of copper accumulation in the sediment has not been quantitatively characterized. In the present study, between 2006 and 2017, copper concentrations were measured in the sediment from selected lakes in New York State with different histories of copper-based aquatic algaecide treatment. Analysis of these data confirmed findings from earlier studies conducted by New York State that lakes with histories of copper treatment have significantly higher copper concentrations in the sediment. It also demonstrated that sediment copper concentrations were significantly higher in the sublittoral zone than the littoral zone in treated lakes. Moreover, a positive correlation was detected between sediment copper concentrations and the total number of treatments with copper-based aquatic algaecide for both littoral and sublittoral zones (p-value = 7.94 × 10-8 and 3.1 × 10-13, respectively). This relationship can be used as a screening tool for regulatory agencies to identify lakes with sediment copper levels possibly higher than the toxicity threshold for aquatic life. Consequently, additional ecological risk assessment may be required before allowing future treatment with copper-based aquatic algaecides. Integr Environ Assess Manag 2024;20:1586-1597. © 2024 SETAC.
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Cobre , Monitoreo del Ambiente , Sedimentos Geológicos , Lagos , Contaminantes Químicos del Agua , Lagos/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Cobre/toxicidad , Sedimentos Geológicos/química , Monitoreo del Ambiente/métodos , New York , Herbicidas/toxicidad , Herbicidas/análisis , Floraciones de Algas NocivasRESUMEN
SUMMARY: We are building the world's first Virtual Child-a computer model of normal and cancerous human development at the level of each individual cell. The Virtual Child will "develop cancer" that we will subject to unlimited virtual clinical trials that pinpoint, predict, and prioritize potential new treatments, bringing forward the day when no child dies of cancer, giving each one the opportunity to lead a full and healthy life.
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Neoplasias , Humanos , Neoplasias/genéticaRESUMEN
Cancer advocates and researchers share the same goal of driving science forward to create new therapies to cure more patients. The power of combining cancer researchers and advocates has become of increased importance due to their complementary expertise. Therefore, advocacy is a critical component of grant structures and has become embedded into the Stand Up 2 Cancer (SU2C) applications. To date, the optimal way to combine these skillsets and experiences to benefit the cancer community is currently unknown. The Saint Baldrick's Foundation (SBF)-SU2C now called St. Baldrick's Empowering Pediatric Immunotherapies for Childhood Cancer (EPICC) Team is comprised of a collaborative network across nine institutions in the United States and Canada. Since SU2C encourages incorporating advocacy into the team structure, we have assembled a diverse team of advocates and scientists by nominating a young investigator (YI) and advocate from each site. In order to further bridge this interaction beyond virtual monthly and yearly in person meetings, we have developed a questionnaire and conducted interviews. The questionnaire is focused on understanding each member's experience at the intersection between science/advocacy, comparing to previous experiences, providing advice on incorporating advocacy into team science and discussing how we can build on our work. Through creating a YI and advocate infrastructure, we have cultivated a supportive environment for meaningful conversation that impacts the entire research team. We see this as a model for team science by combining expertise to drive innovation forward and positively impact pediatric cancer patients, and perhaps those with adult malignancies. Significance: Questionnaire results show both advocates and YI's see this structure to be valuable and beneficial. YI's communicated their research to a non-scientific audience and learned advocate's experience. This was their first advocacy experience for most YIs. Advocates learned more about the research being conducted to provide hope. They can also aid with fundraising, publicity and lobbying. This collaboration improves science communication, designing patient-friendly clinical trials and sharing experience across institutions.
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Headwater streams are critical components of the stream network, yet landowner perceptions, attitudes, and property management behaviors surrounding these intermittent and ephemeral streams are not well understood. Our research uses the concept of watershed disproportionality, where coupled social-biophysical conditions bear a disproportionate responsibility for harmful water quality outcomes, to analyze the potential influence of riparian landowner perceptions and attitudes on water quality in headwater regions. We combine social science survey data, aerial imagery, and an analysis of spatial point processes to assess the relationship between riparian landowner perceptions and attitudes in relation to stream flow regularity. Stream flow regularity directly and positively shapes landowners' water quality concerns, and also positively influences landowners' attitudes of stream importance-a key determinant of water quality concern as identified in a path analysis. Similarly, riparian landowners who do not notice or perceive a stream on their property are likely located in headwater regions. Our findings indicate that landowners of headwater streams, which are critical areas for watershed-scale water quality, are less likely to manage for water quality than landowners with perennial streams in an obvious, natural channel. We discuss the relationships between streamflow and how landowners develop understandings of their stream, and relate this to the broader water quality implications of headwater stream mismanagement.
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Ríos , Calidad del Agua , Agua/análisisRESUMEN
The contribution of runoff from various land uses to stream channels in a watershed is often speculated and used to underpin many model predictions. However, these contributions, often based on little or no measurements in the watershed, fail to appropriately consider the influence of the hydrologic location of a particular landscape unit in relation to the stream network. A simple model was developed to predict storm runoff and the phosphorus (P) status of a perennial stream in an urban watershed in New York State using the covariance structure of runoff from different landscape units in the watershed to predict runoff in time. One hundred and twenty-seven storm events were divided into parameterization (n = 85) and forecasting (n = 42) data sets. Runoff, dissolved P (DP), and total P (TP) were measured at nine sites distributed among three land uses (high maintenance, unmaintained, wooded), three positions in the watershed (near the outlet, midwatershed, upper watershed), and in the stream at the watershed outlet. The autocorrelation among runoff and P concentrations from the watershed landscape units (n = 9) and the covariance between measurements from the landscape units and measurements from the stream were calculated and used to predict the stream response. Models, validated using leave-one-out cross-validation and a forecasting method, were able to correctly capture temporal trends in streamflow and stream P chemistry (Nash-Sutcliffe efficiencies, 0.49-0.88). The analysis suggests that the covariance structure was consistent for all models, indicating that the physical processes governing runoff and P loss from these landscape units were stationary in time and that landscapes located in hydraulically active areas have a direct hydraulic link to the stream. This methodology provides insight into the impact of various urban landscape units on stream water quantity and quality.
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Ciudades , Monitoreo del Ambiente/métodos , Ríos/química , Movimientos del Agua , Contaminantes Químicos del Agua/química , Predicción , Modelos Teóricos , Fósforo/química , LluviaRESUMEN
As part of the Deepwater Horizon Oil Spill Natural Resource Damage Assessment in the Gulf of Mexico, we conducted a large passive acoustic survey across the eastern Gulf continental shelf edge to assess impacts to sperm whale population. In the months immediately after the spill, sperm whale occurrence was significantly higher in areas closest to the spill. Over the following seasons in 2010-2011, we documented cyclical patterns of decreased and increased occurrence suggesting that this population exhibits a seasonal occurrence pattern in the region, with seasonal movements to other regions, and not likely directly influenced by the oil spill. Unfortunately, a lack of adequately scaled, pre-spill data on sperm whales, along with limitations on the survey duration constrain our ability to infer spill-related changes in sperm whale occurrence. However, our study establishes post-disaster baseline data for continued monitoring, and an expanded study design could provide a model for continued monitoring.
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Contaminación por Petróleo , Contaminantes Químicos del Agua , Animales , Monitoreo del Ambiente , Golfo de México , Estaciones del Año , Cachalote , Contaminantes Químicos del Agua/análisisRESUMEN
Population control through harvest has the potential to reduce the abundance of nuisance and invasive species. However, demographic structure and density-dependent processes can confound removal efforts and lead to undesirable consequences, such as overcompensation (an increase in abundance in response to harvest) and instability (population cycling or chaos). Recent empirical studies have demonstrated the potential for increased mortality (such as that caused by harvest) to lead to overcompensation and instability in plant, insect, and fish populations. We developed a general population model with juvenile and adult stages to help determine the conditions under which control harvest efforts can produce unintended outcomes. Analytical and simulation analyses of the model demonstrated that the potential for overcompensation as a result of harvest was significant for species with high fecundity, even when annual stage-specific survivorship values were fairly low. Population instability as a result of harvest occurred less frequently and was only possible with harvest strategies that targeted adults when both fecundity and adult survivorship were high. We considered these results in conjunction with current literature on nuisance and invasive species to propose general guidelines for assessing the risks associated with control harvest based on life history characteristics of target populations. Our results suggest that species with high per capita fecundity (over discrete breeding periods), short juvenile stages, and fairly constant survivorship rates are most likely to respond undesirably to harvest. It is difficult to determine the extent to which overcompensation and instability could occur during real-world removal efforts, and more empirical removal studies should be undertaken to evaluate population-level responses to control harvests. Nevertheless, our results identify key issues that have been seldom acknowledged and are potentially generic across taxa.
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Conservación de los Recursos Naturales , Ecosistema , Modelos Biológicos , Animales , Dinámica PoblacionalRESUMEN
Dams are known to trap pollutants such as metals and PCBs in the sediment that accumulates within their reservoirs. As more attention is paid to microplastics, an emerging contaminant in waterways worldwide, and how they move along rivers, whether microplastic particles also accumulate behind dams is an important question for informing estimates of global river inputs to oceans. In this study, we measured microplastic concentrations above, below, and within the reservoirs of six dams near Ithaca, NY USA. Samples were processed following the wet peroxide oxidation method and visual counting, followed by Raman Spectroscopy validation. We found that microplastic concentrations in sediment within reservoirs was significantly higher than in sediment above the dams (pâ¯=â¯0.005), and in water samples, concentrations within reservoirs was significantly lower (pâ¯=â¯0.02). Plastic fibers were the dominant plastic type, but in within-reservoir sediment samples, less abundant plastic types such as plastic fragments were found in higher proportions. These results show that the sediment collecting behind dams is one sink for microplastics in river systems at long timescales, indicating that accounting for dams may be important when modeling global riverine microplastic transport.
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Microplastics, particles less than 5 mm in size, are an emerging contaminant in waterways worldwide. Most microplastic studies focus on spatial trends in concentration, but in systems as dynamic as rivers, to draw conclusions from existing spatial studies, we must first examine how microplastic concentrations may change with time and flow conditions. In this study, we investigate how microplastic concentrations change over a 24-h period and between seasonally high and low flows. We do this in two streams, controlling for wastewater treatment strategy: one stream in a watershed where waste is treated with septic systems and the other receiving wastewater treatment plant effluent. We hypothesized that a stream with wastewater treatment plant effluent would exhibit higher and more variable microplastic concentrations than a stream in a watershed with septic systems. Results indicate, however, that there is no significant difference between the two streams despite their differing treatment strategies. Additionally, no significant variation in concentrations was measured over two 24-h sampling campaigns. There was, however, significantly higher concentrations measured in summer low flow conditions relative to spring high flow conditions across both sampled streams (p value <0.001), indicating that increases in stream discharge unrelated to storm events dilute and decrease measured microplastic concentrations. From this, we learn that pairing measured concentrations with a description of flow conditions at sampling time is a requisite for a robust microplastic literature that allows for comparisons between existing spatial studies and extrapolations to global loads.
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Plásticos/análisis , Ríos , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , New York , Estaciones del AñoRESUMEN
OBJECTIVE: To explore whether early analysis of spatial data may result in identification of variables associated with epidemic spread of foot and mouth disease. SAMPLE POPULATION: 37 farms with infected cattle (ie, case farms) reported within the first 6 days of the 2001 Uruguayan foot-and-mouth disease epidemic. PROCEDURE: A georeferenced database was created and retrospective analysis was performed on case farm location in relation to farm density, cattle density, farm type (ie, beef vs dairy cattle production), road density, case farm distance to the nearest road, farm size, farm ownership, and day of infection. Mean or median results of 1 to 3 day versus 4 to 6 day spatial data were compared. Spatial-temporal associations were investigated by correlation analysis. RESULTS: Comparison of mean or median values between the first 3 days and days 4 to 6 of the epidemic and results of correlation analysis indicated a significant increase in road density, cattle density, and dairy cattle production and a significant decrease in farm size and case farm distance to the nearest road that developed over time. A route that linked most case farms by the shortest possible distance and also considered significantly associated variables was created. It included 86.1% of all case farms reported by 60 days into the epidemic. CONCLUSIONS AND CLINICAL RELEVANCE: Epidemic direction can be assessed on the basis of road density and other spatial variables as early as 6 days into an epidemic. Epidemic control areas may be more effectively identified if local and regional georeferenced data are considered.