142 research outputs found

    Widespread forest vertebrate extinctions induced by a mega hydroelectric dam in lowland Amazonia

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    Mega hydropower projects in tropical forests pose a major emergent threat to terrestrial and freshwater biodiversity worldwide. Despite the unprecedented number of existing, underconstruction and planned hydroelectric dams in lowland tropical forests, long-term effects on biodiversity have yet to be evaluated. We examine how medium and large-bodied assemblages of terrestrial and arboreal vertebrates (including 35 mammal, bird and tortoise species) responded to the drastic 26-year post-isolation history of archipelagic alteration in landscape structure and habitat quality in a major hydroelectric reservoir of Central Amazonia. The Balbina Hydroelectric Dam inundated 3,129 km2 of primary forests, simultaneously isolating 3,546 land-bridge islands. We conducted intensive biodiversity surveys at 37 of those islands and three adjacent continuous forests using a combination of four survey techniques, and detected strong forest habitat area effects in explaining patterns of vertebrate extinction. Beyond clear area effects, edge-mediated surface fire disturbance was the most important additional driver of species loss, particularly in islands smaller than 10 ha. Based on species-area models, we predict that only 0.7% of all islands now harbor a species-rich vertebrate assemblage consisting of ≥80% of all species. We highlight the colossal erosion in vertebrate diversity driven by a man-made dam and show that the biodiversity impacts of mega dams in lowland tropical forest regions have been severely overlooked. The geopolitical strategy to deploy many more large hydropower infrastructure projects in regions like lowland Amazonia should be urgently reassessed, and we strongly advise that long-term biodiversity impacts should be explicitly included in pre-approval environmental impact assessments

    PAKs supplement improves immune status and body composition but not muscle strength in resistance trained individuals

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    Mixed formula supplements are very popular among recreational and professional weightlifters. They are usually known as PAKs and they are supposed to have a synergistic effect of their different nutrients. The purpose of this study was to determine the effects of chronic (4 weeks) PAKS supplementation in combination with strength training on body composition, immune status and performance measures in recreationally trained individuals with or without PAKs supplementation. Methods: Twelve male subjects (Placebo n = 6 and PAKs supplement n = 6) were recruited for this study. The body composition, one maximum strength repetition tests and immune status were assessed before and after 4 week supplementation. Our data showed that, 4 week PAK supplementation associated with strength exercise not was effective in change strength than compared with placebo group. However, we observed that, PAK supplement was able to improve immune status and reduced body composition when compared with placebo group. These results indicate that, a mixed formula supplement is able to improve immune status and body composition but not maximum strength in recreational strength trained subjects in a 4 weeks period

    Omics Approaches for Understanding Biogenesis, Composition and Functions of Fungal Extracellular Vesicles

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    This is the final version. Available on open access from Frontiers Media via the DOI in this recordExtracellular vesicles (EVs) are lipid bilayer structures released by organisms from all kingdoms of life. The diverse biogenesis pathways of EVs result in a wide variety of physical properties and functions across different organisms. Fungal EVs were first described in 2007 and different omics approaches have been fundamental to understand their composition, biogenesis, and function. In this review, we discuss the role of omics in elucidating fungal EVs biology. Transcriptomics, proteomics, metabolomics, and lipidomics have each enabled the molecular characterization of fungal EVs, providing evidence that these structures serve a wide array of functions, ranging from key carriers of cell wall biosynthetic machinery to virulence factors. Omics in combination with genetic approaches have been instrumental in determining both biogenesis and cargo loading into EVs. We also discuss how omics technologies are being employed to elucidate the role of EVs in antifungal resistance, disease biomarkers, and their potential use as vaccines. Finally, we review recent advances in analytical technology and multi-omic integration tools, which will help to address key knowledge gaps in EVs biology and translate basic research information into urgently needed clinical applications such as diagnostics, and immuno- and chemotherapies to fungal infections.NIHPacific Northwest National Laboratory (PNNL)CNPq/Science Without Borders Science Program, BrazilJohns Hopkins Malaria Research InstituteFAPESPCAPESCNPqMedical Research Council (MRC

    Bootstrapping Q Methodology to Improve the Understanding of Human Perspectives.

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    Q is a semi-qualitative methodology to identify typologies of perspectives. It is appropriate to address questions concerning diverse viewpoints, plurality of discourses, or participation processes across disciplines. Perspectives are interpreted based on rankings of a set of statements. These rankings are analysed using multivariate data reduction techniques in order to find similarities between respondents. Discussing the analytical process and looking for progress in Q methodology is becoming increasingly relevant. While its use is growing in social, health and environmental studies, the analytical process has received little attention in the last decades and it has not benefited from recent statistical and computational advances. Specifically, the standard procedure provides overall and arguably simplistic variability measures for perspectives and none of these measures are associated to individual statements, on which the interpretation is based. This paper presents an innovative approach of bootstrapping Q to obtain additional and more detailed measures of variability, which helps researchers understand better their data and the perspectives therein. This approach provides measures of variability that are specific to each statement and perspective, and additional measures that indicate the degree of certainty with which each respondent relates to each perspective. This supplementary information may add or subtract strength to particular arguments used to describe the perspectives. We illustrate and show the usefulness of this approach with an empirical example. The paper provides full details for other researchers to implement the bootstrap in Q studies with any data collection design

    Cortical Thinning in Patients with Recent Onset Post-Traumatic Stress Disorder after a Single Prolonged Trauma Exposure

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    Most of magnetic resonance imaging (MRI) studies about post-traumatic stress disorder (PTSD) focused primarily on measuring of small brain structure volume or regional brain volume changes. There were rare reports investigating cortical thickness alterations in recent onset PTSD. Recent advances in computational analysis made it possible to measure cortical thickness in a fully automatic way, along with voxel-based morphometry (VBM) that enables an exploration of global structural changes throughout the brain by applying statistical parametric mapping (SPM) to high-resolution MRI. In this paper, Laplacian method was utilized to estimate cortical thickness after automatic segmentation of gray matter from MR images under SPM. Then thickness maps were analyzed by SPM8. Comparison between 10 survivors from a mining disaster with recent onset PTSD and 10 survivors without PTSD from the same trauma indicates cortical thinning in the left parietal lobe, right inferior frontal gyrus, and right parahippocampal gyrus. The regional cortical thickness of the right inferior frontal gyrus showed a significant negative correlation with the CAPS score in the patients with PTSD. Our study suggests that shape-related cortical thickness analysis may be more sensitive than volumetric analysis to subtle alteration at early stage of PTSD

    Forest Fruit Production Is Higher on Sumatra Than on Borneo

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    BACKGROUND: Various studies have shown that the population densities of a number of forest vertebrates, such as orangutans, are higher on Sumatra than Borneo, and that several species exhibit smaller body sizes on Borneo than Sumatra and mainland Southeast Asia. It has been suggested that differences in forest fruit productivity between the islands can explain these patterns. Here we present a large-scale comparison of forest fruit production between the islands to test this hypothesis. METHODOLOGY/PRINCIPAL FINDINGS: Data on fruit production were collated from Sumatran and Bornean sites. At six sites we assessed fruit production in three forest types: riverine, peat swamp and dryland forests. We compared fruit production using time-series models during different periods of overall fruit production and in different tree size classes. We examined overall island differences and differences specifically for fruiting period and tree size class. The results of these analyses indicate that overall the Sumatran forests are more productive than those on Borneo. This difference remains when each of the three forest types (dryland, riverine, and peat) are examined separately. The difference also holds over most tree sizes and fruiting periods. CONCLUSIONS/SIGNIFICANCE: Our results provide strong support for the hypothesis that forest fruit productivity is higher on Sumatra than Borneo. This difference is most likely the result of the overall younger and more volcanic soils on Sumatra than Borneo. These results contribute to our understanding of the determinants of faunal density and the evolution of body size on both islands

    Vitimização por homicídios segundo características de raça no Brasil

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    OBJETIVO: Descrever a tendência temporal da mortalidade por homicídio no Brasil. MÉTODOS: Estudo de série temporal dos homicídios no Brasil de 2000 a 2009. As variáveis explicativas foram raça/cor, sexo e escolaridade. Os óbitos foram provenientes do Sistema de Informações de Mortalidade. A análise de tendência foi realizada por meio de regressão polinomial para séries históricas (p < 0,05; intervalo de 95% de confiança). RESULTADOS: A população negra representou 69% das vítimas de homicídios em 2009. O número de homicídios aumentou entre a população negra e diminuiu entre a branca, com tendência de crescimento da taxa nos negros e de redução nos brancos no período. As taxas aumentaram nos grupos de maior e menor escolaridade entre negros, enquanto, entre brancos, reduziram para os de menor nível escolar e mantiveram-se estáveis no grupo com maior nível de escolaridade. Em 2009 negros tiveram maior risco de morte por homicídios do que a população branca, independentemente do nível de escolaridade. Entre 2004 e 2009, as taxas de homicídios na população branca diminuíram e aumentaram na negra. CONCLUSÕES: O risco relativo de homicídios cresce na população negra, sugerindo o aumento das desigualdades. A repercussão das medidas antiarmas no Brasil, implantada em 2004, foi positiva na população branca e discreta na população negra. Raça/cor pode predizer a ocorrência de homicídio.OBJETIVO: Describir la tendencia temporal de la mortalidad por homicidio en Brasil. MÉTODOS: Estudio de serie temporal de los homicidios en Brasil de 2000 a 2009. Las variables explicativas fueron raza/color, sexo y escolaridad. Los óbitos fueron provenientes del Sistema de Informaciones de Mortalidad. El análisis de tendencia fue realizada por medio de regresión polinomial para series históricas (pOBJECTIVE: To describe the temporal patterns of mortality by homicide in Brazil. METHODS: A series of homicides in Brazil from 2000 to 2009 were studied. The explanatory variables were race/skin color, gender and education. The death statistics were obtained from the Mortality Information System. A trend analysis was performed by means of a polynomial regression for a historic time series (p < 0.05, 95% confidence interval). RESULTS: The black population represented 69% of the homicide victims in 2009. The homicide rate increased in the black population, while it decreased in the white population in the period studied. The homicide rate increased in groups with both higher and lower education among blacks; among whites, the rate decreased for those with the lowest level of schooling and remained stable in the group with higher educational levels. In 2009, blacks had a higher risk of death than whites from homicide, regardless of education level. Between 2004 and 2009, the homicide rate decreased in the white population, while it increased in the black population. CONCLUSIONS: The relative risk of falling victim to homicide increased in the black population, suggesting an increase in inequality. The effect of the anti-gun measures implemented in Brazil in 2004 was positive in the white population and less pronounced in the black population. Overall, race/skin color predicted the occurrence of homicide
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