1,064 research outputs found

    An assessment of sampling biases across studies of diel activity patterns in marine ray-finned fishes (Actinopterygii)

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    Author Posting. © University of Miami - Rosenstiel School of Marine and Atmospheric Science, 2016. This article is posted here by permission of University of Miami - Rosenstiel School of Marine and Atmospheric Science for personal use, not for redistribution. The definitive version was published in Bulletin of Marine Science 93 (2017): 611-639, doi:10.5343/bms.2016.1016.Understanding the promotion and regulation of circadian rhythms in marine fishes is important for studies spanning conservation, evolutionary biology, and physiology. Given numerous challenges inherent to quantifying behavioral activity across the full spectrum of marine environments and fish biodiversity, case studies offer a tractable means of gaining insights or forecasting broad patterns of diel activity. As these studies continue to accumulate, assessing whether, and to what extent, the cumulatively collected data are biased in terms of geography, habitat, or taxa represents a fundamentally important step in the development of a broad overview of circadian rhythms in marine fish. As such investigations require a phylogenetic framework, general trends in the phylogenetic sampling of marine fishes should be simultaneously assessed for biases in the sampling of taxa and trait data. Here, we compile diel activity data for more than 800 marine species from more than five decades of scientific studies to assess general patterns of bias. We found significant geographic biases that largely reflect a preference toward sampling warm tropical waters. Additionally, taxonomic biases likewise reflect a tendency toward conspicuous reef associated clades. Placing these data into a phylogenetic framework that includes all known marine fishes revealed significant under-dispersion of behavioral data and taxon sampling across the whole tree, with a few subclades exhibiting significant over-dispersion. In total, our study illuminates substantial gaps in our understanding of diel activity patterns and highlights significant sampling biases that have the potential to mislead evolutionary or ecological analyses.Partial funding was provided by the North Carolina Museum of Natural Sciences

    The effects of climate change on Australia’s only endemic Pokémon: Measuring bias in species distribution models

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    1. Species distribution models (SDMs) are frequently used to predict the effects of climate change on species of conservation concern. Biases inherent in the process of constructing SDMs and transferring them to new climate scenarios may result in undesirable conservation outcomes. We explore these issues and demonstrate new methods to estimate biases induced by the design of SDM studies. We present these methods in the context of estimating the effects of climate change on Australia\u27s only endemic Pokémon.2. Using a citizen science dataset, we build species distribution models for Garura kangaskhani to predict the effects of climate change on the suitability of habitat for the species. We demonstrate a novel Monte Carlo procedure for estimating the biases implicit in a given study design, and compare the results seen for Pokémon to those seen from our Monte Carlo tests as well as previous studies in the same region using both simulated and real data.3. Our models suggest that climate change will impact the suitability of habitat for G. kangaskhani, which may compound the effects of threats such as habitat loss and their use in blood sport. However, we also find that using SDMs to estimate the effects of climate change can be accompanied by biases so strong that the data themselves have minimal impact on modelling outcomes. 4. We show that the direction and magnitude of bias in estimates of climate change impacts are affected by every aspect of the modelling process, and suggest that bias estimates should be included in future studies of this type. Given the widespread use of SDMs, systemic biases could have substantial financial and opportunity costs. By demonstrating these biases and presenting a novel statistical tool to estimate them, we hope to provide a more secure future for G. kangaskhani and the rest of the world\u27s biodiversity

    Prevalence of asthma and rhinitis symptoms in a Coruña (Spain)

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    Ponencia presentada en el IV Congreso de la Sociedad de Pediatría de Galicia, Verín, 2004[Resumen] Introducción. El asma y la rinitis son dos enfermedades con elevada prevalencia en la infancia, con tendencia a incrementarse en los últimos años. En ambas es frecuente el infradiagnóstico. Objetivo. Verificar la prevalencia de síntomas de asma y rinitis en la población infantil. Material y métodos. Hemos realizado, mediante cuestionario escrito, un estudio transversal siguiendo la metodología del International Study of Asthma and Allergies in Childhood (ISAAC), de prevalencia de sintomatología de asma y rinitis en el área de A Coruña. Resultados. Han sido incluidos 3.017 niños y niñas de 6 y 7 años (tasa de respuesta del 73,9%), y 2.981 de 13 y 14 años (tasa de respuesta del 93,6%). Refirieron haber presentado sibilancias alguna vez el 25,3% de los niños y niñas de 13 y 14 años y el 37,2% de los de 6 y 7 años. Han presentado asma en alguna ocasión el 18,5% de los adolescentes y el 13,7 % del grupo de menor edad. La prevalencia de rinitis alguna vez fue del 30,4% a los 6 y 7 años y del 47,3% a los 13 y 14 años. La mayor prevalencia de rinitis se produjo en el otoño. Conclusiones. El asma y la rinitis son especialmente frecuentes en nuestra población, superior a la observada en la mayoría de poblaciones españolas estudiadas.[Abstract] Introduction. The prevalence of asthma and rhinitis is high in childhood and has been increasing in the last few years. In both diseases underdiagnosis is frequent. Objective. To asses the prevalence of asthma and rhinitis symptoms in childhood. Material and methods. We performed a cross-sectional study using a written questionnaire, following the methodology of the International Study of Asthma and Allergies in Childhood (ISAAC), on the prevalence of symptoms of asthma and rhinitis in La Coruña. Results. A total of 3017 boys and girls aged 6-7 years old (response rate 73.9 %) and 2981 boys and girls aged 13-14 years old (response rate 93.6 %) were included. The prevalence of “wheezing at some time” was 25.3% in adolescents aged 13-14 years old and was 37.2 % in children aged 6-7 years. The prevalence of “asthma at some time” was 18.5% in adolescents and 13.7% in children. The prevalence of “rhinitis at some time” was 30.4% in the group aged 6-7 years and 47.3% in the group of adolescents. The prevalence of rhinitis was highest in autumn. Conclusions. The prevalence of asthma and rhinitis is high in our population and is higher than that observed in most Spanish populations studied

    La sobrehidratación persistente asocia un riesgo significativo de infección peritoneal por gérmenes entéricos en pacientes tratados con diálisis peritoneal

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    [Abstract] Background: Overhydration (OH) complicates frequently the clinical course of Peritoneal Dialysis (PD) patients, and keeps a controversial association with the risk of peritoneal infection. The main objective of this study was to disclose an association between persistent OH and the risk of enteric peritonitis in a relatively large sample of patients undergoing PD. Method: Following a prospective design, we monitorized systematically body composition of patients treated with PD in our unit (2011–2016), searching for a correlation with the ensuing risk of peritonitis, with an emphasis on the association between persistent OH (main study variable) and the risk of infection by enteric pathogens (main outcome). Essential demographic, clinical and laboratory variables with a potential influence on the risk of peritonitis were recorded. We used multivariate survival analysis to clarify the specific effect of different body composition parameters on the main outcome. Main results: We included 139 patients for analysis (mean follow-up 24 months). Sixty-three patients suffered at least one peritonitis, and 17 had at least one diagnosis of enteric peritonitis. Univariate analysis disclosed a general trend to an increased risk of enteric peritonitis in overhydrated patients, as evidenced by associations of this outcome with mean extracellular water/intracellular water (ECW/ICW)(p = 0007), OH/ECW (p = 0033) and ECW/total body water (ECW/TBW)(p = 0004) ratios, but not with absolute OH values. Multivariate analysis confirmed similar associations or trends (RR 3,48, 95 % CI 1,03–14,59, p = 0,046, highest versus lowest tertile of ECW/ICW, RR 2,31, 95 % CI 0,98-6,56, p = 0,061, highest versus lowest tertile of OH/ECW, and RR 6,33, 95 % CI 1,37-19,37, p = 0,011, highest versus lowest tertile of ECW/TBW). On the contrary, no apparent association was detected between OH and the overall risk of peritoneal infection.[Resumen] Antecedentes y objetivos. La sobrehidratación (SH) es frecuente, y a menudo persistente, en pacientes tratados con diálisis peritoneal (DP), y mantiene una asociación controvertida con el riesgo de infección peritoneal. El objetivo principal de este estudio fue desvelar una posible asociación entre la presencia de SH y el riesgo subsiguiente de infección peritoneal por gérmenes entéricos, en una población relativamente amplia de pacientes tratados con DP. Método Según diseño prospectivo, monitorizamos de manera sistemática la composición corporal de pacientes tratados con DP en nuestra unidad (2011-2016), buscando una posible correlación con el riesgo de peritonitis durante el seguimiento, con un interés particular en la asociación entre SH persistente (variable de estudio principal) y el riesgo de infección peritoneal por patógenos entéricos (variable resultado principal). Para el análisis tuvimos en cuenta variables demográficas, clínicas y de laboratorio con influencia potencial en el riesgo de infección peritoneal. Utilizamos técnicas de análisis multivariante para clarificar el efecto específico de diferentes parámetros de composición corporal sobre la variable resultado principal. Resultados principales. Incluimos 139 pacientes, con seguimiento medio de 24 meses. Sesenta y tres pacientes sufrieron al menos una peritonitis, y 17 al menos una infección por gérmenes entéricos. El análisis univariante mostró una tendencia general a mayor riesgo de infección peritoneal entérica en pacientes sobrehidratados, que se hacía evidente cuando se usaba el cociente agua extracelular/agua intracelular (AEC/AIC) (p=0,007), el cociente SH/AEC (SH/AEG) (p=0,033), o el cociente AEC/agua corporal total (AEC/ACT) (p=0,004), pero no cuando se usaba la SH absoluta, como variable de estudio. El análisis multivariante confirmó estas asociaciones o tendencias (RR: 3,48; IC 95%: 1,03-14,59; p=0,046, tercil mayor versus menor para AEC/AIC, RR: 2,31; IC 95%: 0,98-6,56; p=0,061, tercil mayor versus menor para SH/AEC, y RR: 6,33; IC 95%: 1,37-19,37; p=0,011, tercil mayor versus menor para AEC/ACT). Por el contrario, no observamos asociación consistente entre SH y riesgo general de infección peritoneal. Conclusión. La SH persistente asocia un riesgo significativo de infección peritoneal por patógenos entéricos, en pacientes tratados con DP

    Disentangling the influence of urbanization and invasion on endemic geckos in tropical biodiversity hot spots : a case study of Phyllodactylus martini (Squamata: Phyllodactylidae) along an Urban Gradient in Curaçao

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    Author Posting. © Peabody Museum of Natural History, 2016. This article is posted here by permission of Peabody Museum of Natural History for personal use, not for redistribution. The definitive version was published in Bulletin of the Peabody Museum of Natural History 57(2016): 147–164, doi:10.3374/014.057.0209.Predicting the response of endemic species to urbanization has emerged as a fundamental challenge in 21st century conservation biology. The factors that underlie population declines of reptiles are particularly nebulous, as these are often the least understood class of vertebrates in a given community. In this study, we assess correlations between feeding ecology and phenotypic traits of the Lesser Antillean endemic Dutch leaf-toed gecko, Phyllodactylus martini, along an urban gradient in the Caribbean island of Curaçao. There has been a marked decline of this species in developed habitats associated with the invasive tropical house gecko Hemidactylus mabouia. We find a correlation between aspects of locomotor morphology and prey in undeveloped habitats that is absent in developed habitats. Analyses of stomach contents further suggest that Phyllodactylus martini alters primary prey items in developed areas. However, changes in prey promote the overlap in foraging niches between Phyllodactylus martini and Hemidactylus mabouia, suggesting that direct resource competition is contributing to the decline of Phyllodactylus martini. In addition to competitive exclusion, we suggest that the urban extirpation of Phyllodactylus martini could also be attributed to a top-down control on population growth by Hemidactylus mabouia. Colonizations of walls put Phyllodactylus martini in direct contact with Hemidactylus mabouia increasing the chances for predation events, as evidenced by our observation of a predation event on a Phyllodactylus martini juvenile by an adult Hemidactylus mabuoia. In total, our results add to a growing body of literature demonstrating the threat that invasive synanthropic reptiles pose to endemics that might otherwise be able to cope with increased urbanization pressures

    Reevaluating claims of ecological speciation in Halichoeres bivittatus

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    Allopatry has traditionally been viewed as the primary driver of speciation in marine taxa, but the geography of the marine environment and the larval dispersal capabilities of many marine organisms render this view somewhat questionable. In marine fishes, one of the earliest and most highly cited empirical examples of ecological speciation with gene flow is the slippery dick wrasse, Halichoeres bivittatus. Evidence for this cryptic or incipient speciation event was primarily in the form of a deep divergence in a single mitochondrial locus between the northern and southern Gulf of Mexico, combined with a finding that these two haplotypes were associated with different habitat types (“tropical” vs. “subtropical”) in the Florida Keys and Bermuda, where they overlap. Here, we examine habitat assortment in the Florida Keys using a broader sampling of populations and habitat types than were available for the original study. We find no evidence to support the claim that haplotype frequencies differ between habitat types, and little evidence to support any differences between populations in the Keys. These results undermine claims of ecological speciation with gene flow in Halichoeres bivittatus. Future claims of this type should be supported by multiple lines of evidence that illuminate potential mechanisms and allow researchers to rule out alternative explanations for spatial patterns of genetic differences

    SEOM clinical guideline thyroid cancer (2019)

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    Thyroid carcinoma is the most frequent endocrine malignancy and accounts for around 3% of global cancer incidence. Different histologies and clinical scenarios make necessary a multidisciplinary approach that includes new diagnostic methods and surgical, radiopharmaceutical and systemic therapies. This guideline updates several aspects of management of thyroid cancer
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