1,744 research outputs found
Are we selecting appropriate metrics to assess human impacts on biodiversity?
Biased and subjective choices in the variable selection processes used in ecological studies commonly lead researchers to reach misleading conclusions regarding patterns of biodiversity response to disturbances. Nevertheless, little attention has been given to these processes in the majority of studies published to date. Here, we assess the extent to which variables commonly employed in ecological studies correspond to those deemed to be most important by researchers of the same studies. Specifically, we examined both biodiversity (response) and environmental (explanatory) metrics from a comprehensive literature review and compared their use with their relative importance, according to a survey with the studies’ authors. We used the literature concerning land use change effects on dung beetles as our study case. Our results highlight marked disparities between researchers opinion and their choice of variables in published papers. We suggest that these disparities are due to the high costs of sampling and processing some variables, as well as to logistical constraints and researchers own bias. If current practices and these discrepancies persist then our understanding of the biodiversity consequences of land-use change will remain compromised, while further undermining our confidence in the results of ecological studies
Relato de caso de miastenia grave infantil / Case report of serious child miastenia
Introdução : A Miastenia Grave ou Myasthenia Gravis ( MG ) é uma doença autoimune da junção neuromuscular na qual ocorre a produção de anticorpos que atuam contra os receptores nicotínicos da acetilcolina, localizados na membrana pós - sináptica da placa motora. Foi internado no Instituto da Saúde da Criança do Amazonas - ICAM com o quadro estável. Mantém as pálpebras semiabertas pela manhã, mas evolui com ptose palpebral e fadiga proeminentes ao final do dia. Ptose palpebral bilateral. Hipótese diagnóstica : Miastenia Grave. Resultados : Eletroneuromiografia compatível com Miastenia Grave de 06/10/2017 e Tomografia Computadorizada de Tórax com imagem nodular sugestivo de sombra tímica de 17/11/2017. Conclusão : A Miastenia Grave deve ser encarada como um problema de saúde pública, a investigação deve avançar na tentativa de se encontrar uma solução eficaz, segura, com um perfil de efeitos adversos favorável, que corrija especificamente as alterações imunitárias causadoras da doença, sem comprometer o restante sistema imunitário.
Caracterização morfométrica da bacia hidrográfica do Rio Grande, oeste da Bahia-BA / Morphometric characterization of the Rio Grande basin, west Bahia-BA
O estudo das características morfométrica de uma bacia hidrográfica é importante no entendimento da dinâmica dos processos hidrológicos e no auxílio da gestão e conservação dos recursos hídricos. O presente trabalho tem por objetivo caracterizar a morfometria da bacia hidrográfica do Rio Grande, localizada na Região Oeste do estado da Bahia utilizando o software Qgis. A base de dados constitui no Modelo Digital de Elevação e shapefiles do IBGE. A partir da calculadora de campo do Qgis foram calculados alguns parâmetros, a área da bacia encontrada foi de 72.701,97 km² e o perímetro igual a 1430,593 km. A bacia hidrográfica do Rio Grande tem formato alongado, coeficiente de compacidade de 1,48, fator de forma de 0,29, índice de circularidade de 0,13, índice de sinuosidade de 1,31 e relação de relevo de 0,012. A densidade de drenagem da bacia foi considerada regular (1,33 km km-2). Conforme as características morfométrica, a bacia apresenta susceptibilidade moderada de ocorrência de enchentes em sua extensão em condições normais de precipitação. Palavras-chave: Bacia hidrográfica, morfometria e geoprocessamento
How pervasive is biotic homogenization in human‐modified tropical forest landscapes?
Land-cover change and ecosystem degradation may lead to biotic homogenization, yet our understanding of this phenomenon over large spatial scales and different biotic groups remains weak. We used a multi-taxa dataset from 335 sites and 36 heterogeneous landscapes in the Brazilian Amazon to examine the potential for landscape-scale processes to modulate the cumulative effects of local disturbances. Biotic homogenization was high in production areas but much less in disturbed and regenerating forests, where high levels of among-site and among-landscape β-diversity appeared to attenuate species loss at larger scales. We found consistently high levels of β-diversity among landscapes for all land cover classes, providing support for landscape-scale divergence in species composition. Our findings support concerns that β-diversity has been underestimated as a driver of biodiversity change and underscore the importance of maintaining a distributed network of reserves, including remaining areas of undisturbed primary forest, but also disturbed and regenerating forests, to conserve regional biota
PROSTATECTOMIA : UMA REVISAO ABRANGENTE
Benign Prostatic Hyperplasia (BPH) is a common urological condition in older men, characterized by the non-cancerous growth of the prostate gland. It manifests through lower urinary tract symptoms, such as difficulty in urination, increased urinary frequency, and a sensation of incomplete emptying. The diagnosis involves a comprehensive clinical assessment, including imaging tests and measurement of the prostate-specific antigen (PSA). Exploration of the medical literature reveals a intricate narrative about Benign Prostatic Hyperplasia and its surgical approach, prostatectomy. Prostatectomy is a surgical intervention performed to address prostate conditions, most commonly associated with prostate cancer. There are two main approaches: radical prostatectomy, involving the complete removal of the prostate and sometimes the seminal vesicles; and partial prostatectomy, aiming to preserve part of the gland. Indications for prostatectomy include the stage and aggressiveness of cancer, while complications may involve bleeding, infection, and erectile dysfunction. The choice between approaches depends on the individualized assessment of the patient. The relevance of a multidisciplinary team, including urologists, clinicians, surgeons, psychologists, and other healthcare professionals, resonates as a constant theme. This collaboration is crucial not only in interpreting clinical data but also in considering the psychosocial aspects that impact the patient's journey.A Hiperplasia Prostática Benigna (HPB) é uma condição urológica comum em homens mais velhos, caracterizada pelo crescimento não canceroso da glândula prostática. Manifesta-se por meio de sintomas do trato urinário inferior, como dificuldade em urinar, aumento da frequência urinária e sensação de esvaziamento incompleto. O diagnóstico envolve uma avaliação clínica abrangente, incluindo exames de imagem e mensuração do antígeno prostático específico (PSA). a exploração da literatura médica revela uma narrativa intricada sobre a Hiperplasia Prostática Benigna e sua abordagem cirúrgica, a prostatectomia. A prostatectomia é uma intervenção cirúrgica realizada para tratar condições prostáticas, sendo mais comumente associada ao câncer de próstata. Existem duas abordagens principais: a prostatectomia radical, que envolve a remoção completa da próstata e, às vezes, das vesículas seminais; e a prostatectomia parcial, que busca preservar parte da glândula. Indicações para a prostatectomia incluem o estágio e a agressividade do câncer, enquanto complicações podem envolver sangramento, infecção e disfunção erétil. A escolha entre as abordagens depende da avaliação individualizada do paciente. A relevância da equipe multidisciplinar, permeada por urologistas, clínicos, cirurgiões, psicólogos e outros profissionais de saúde, ressoa como uma constante. Essa colaboração é crucial não apenas na interpretação dos dados clínicos, mas também na consideração dos aspectos psicossociais que impactam a jornada do paciente
Anthropogenic disturbance in tropical forests can double biodiversity loss from deforestation
© 2016 Macmillan Publishers Limited. All rights reserved. Concerted political attention has focused on reducing deforestation, and this remains the cornerstone of most biodiversity conservation strategies. However, maintaining forest cover may not reduce anthropogenic forest disturbances, which are rarely considered in conservation programmes. These disturbances occur both within forests, including selective logging and wildfires, and at the landscape level, through edge, area and isolation effects. Until now, the combined effect of anthropogenic disturbance on the conservation value of remnant primary forests has remained unknown, making it impossible to assess the relative importance of forest disturbance and forest loss. Here we address these knowledge gaps using a large data set of plants, birds and dung beetles (1,538, 460 and 156 species, respectively) sampled in 36 catchments in the Brazilian state of Pará. Catchments retaining more than 69-80% forest cover lost more conservation value from disturbance than from forest loss. For example, a 20% loss of primary forest, the maximum level of deforestation allowed on Amazonian properties under Brazil's Forest Code, resulted in a 39-54% loss of conservation value: 96-171% more than expected without considering disturbance effects. We extrapolated the disturbance-mediated loss of conservation value throughout Pará, which covers 25% of the Brazilian Amazon. Although disturbed forests retained considerable conservation value compared with deforested areas, the toll of disturbance outside Pará's strictly protected areas is equivalent to the loss of 92,000-139,000 km2 of primary forest. Even this lowest estimate is greater than the area deforested across the entire Brazilian Amazon between 2006 and 2015 (ref. 10). Species distribution models showed that both landscape and within-forest disturbances contributed to biodiversity loss, with the greatest negative effects on species of high conservation and functional value. These results demonstrate an urgent need for policy interventions that go beyond the maintenance of forest cover to safeguard the hyper-diversity of tropical forest ecosystems
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