437 research outputs found

    Milder Alzheimer\u27s Disease Pathology in Heart Failure and Atrial Fibrillation

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    Introduction:Heart failure (HF) and atrial fibrillation (AF) have been associated with a higher risk of Alzheimer’s disease (AD). Whether HF and AF are related to AD by enhancing AD neuropathological changes is unknown. Methods:We applied network analyses and multiple logistic regression models to assess the association between HF and AF with severity of AD neuropathology in patients from the National Alzheimer’s Coordinating Center database with primary neuropathological diagnosis of AD. Results:We included 1593 patients, of whom 129 had HF and 250 had AF. HF and AF patients were older and had milder AD pathology. In the network analyses, HF and AF were associated with milder AD neuropathology. In the regression analyses, age (odds ratio [OR] 0.94, 95

    Projections of Brazilian biomes resilience and socio-environmental risks to climate change

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    Climate change has been considered, at a global level, as one of the main anthropogenic drivers of environmental transformation, especially on biomes, ecosystems and the most vulnerable population. In this regard, the concept of resilience has been widely used in ecology to explain the ecosystem transition thresholds by which forests and other habitats are able to restructure in the face of various external disturbances. However, the concept of resilience in facing climate change impacts and risks through the lens of socio-environmental risks in Brazil is still underdeveloped, especially at the biome level. This article uses the theory of critical transitions to ecological niche distribution modeling in future global warming scenarios by the end of the century, in order to highlight the change in ecological resilience of the Amazon, Caatinga, Cerrado, Atlantic Forest and Pampa biomes, and how the changes in resilience can lead to an increased exposure, vulnerabilities and risks to socio-environmental security. This article shows how an interdisciplinary approach bringing together modeling of biome resilience may be a tool to support decision making and public policies on mitigation and adaptation to climate change and reduce risks to socio-environmental security.Climate change has been considered, at a global level, as one of the main anthropogenic drivers of environmental transformation, especially on biomes, ecosystems and the most vulnerable population. In this regard, the concept of resilience has been widely used in ecology to explain the ecosystem transition thresholds by which forests and other habitats are able to restructure in the face of various external disturbances. However, the concept of resilience in facing climate change impacts and risks through the lens of socio-environmental risks in Brazil is still underdeveloped, especially at the biome level. This article uses the theory of critical transitions to ecological niche distribution modeling in future global warming scenarios by the end of the century, in order to highlight the change in ecological resilience of the Amazon, Caatinga, Cerrado, Atlantic Forest and Pampa biomes, and how the changes in resilience can lead to an increased exposure, vulnerabilities and risks to socio-environmental security. This article shows how an interdisciplinary approach bringing together modeling of biome resilience may be a tool to support decision making and public policies on mitigation and adaptation to climate change and reduce risks to socio-environmental security

    Phytosociology and floristic diversity in a cerrado area under different antropization levels, rio pardo de Minas, MG

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    Este estudo teve como objetivo avaliar a diversidade e a similaridade flor\uedstica de ambientes de Cerrado, sob diferentes n\uedveis de antropiza\ue7\ue3o por uso agr\uedcola e extrativismo, e gerar base de dados para subsidiar propostas de desenvolvimento sustent\ue1vel para a regi\ue3o Norte de Minas e sistemas de agricultura tradicional. Foram amostradas 4 \ue1reas nos seguintes ambientes: Arei\ue3o, Arei\ue3ozinho, Chapada de Latossolo e Tabuleiro, cujas identifica\ue7\uf5es foram feitas a partir de informantes-chave na Comunidade \uc1gua Boa, em Rio Pardo de Minas (MG). As unidades amostrais foram distribu\ueddas em 8 parcelas de 20 x 50 m, com 5 subparcelas. Foram medidos indiv\uedduos arb\uf3reos com circunfer\ueancia ao n\uedvel do solo maior ou igual a 15 cm. Para an\ue1lise dos \uedndices fitossociol\uf3gicos foram calculados os par\ue2metros densidade, domin\ue2ncia, freq\ufc\ueancia, \ue1rea basal e valor de import\ue2ncia, para cada ambiente. Para a diversidade flor\uedstica foi calculado o \uedndice de Shannon (H\u2019) e para an\ue1lise da similaridade o \uedndice de Jaccard (Sij). Em todos os ambientes, foi encontrado um total de 477 indiv\uedduos, distribu\ueddos em 21 fam\uedlias, com 48 esp\ue9cies bot\ue2nicas identificadas e 27 indiv\uedduos n\ue3o identificados. As cinco fam\uedlias mais importantes (maior VI) foram Fabaceae/Papilionoideae, Apocynaceae, Vochysiaceae, Sapotaceae e Fabaceae/Caesalpinoideae. J\ue1 as dez esp\ue9cies de maior import\ue2ncia foram Pouteria ramiflora, Dalbergia miscolobium, Hancornia speciosa, Macherium opacum, Sclerolobium paniculatum var. subvelutinum, Qualea grandiflora, Aspidosperma tomentosum, Byrsonima pachyphylla, Vochysia thyrsoidea e Hymenaea stigonocarpa. O \uedndice H\u2019 foi de 3,01; 2,72; 2,48 e 2,09 para Arei\ue3o, Arei\ue3ozinho, Chapada do Latossolo e Tabuleiro, respectivamente. O \uedndice Sij indicou, para todas as combina\ue7\uf5es entre os ambientes, que existia pouca similaridade flor\uedstica entre eles.The objective of the study was to evaluate diversity and floristic similarity of Cerrado environments, under different levels of anthropization for agricultural usage and extractivism, and to generate a database to subsidize sustainable development proposals for the North region of Minas Gerais State, and traditional agriculture systems. Four areas with different levels of anthropization were sampled, in the following environments: "Arei\ue3o, Arei\ue3ozinho, Chapada de Latossolo and Tabuleiro", whose identifications had been made from key informers in the \uc1gua Boa Community, in Rio Pardo de Minas (MG, Brazil). The sampled units were distributed in 8 parcels of 20 x 50 m, with 5 subplots. The trees with circumference at ground level of 15 cm or bigger were measured. For analysis of the phytosociology indexes the following parameters were calculated for each environment: density, dominance, frequency, basal area, and importance value. For the floristic diversity the Shannon (H') was calculated, and for the analysis of similarity the index of Jaccard index (Sij). In all the environments, it was found a total of 477 individuals, distributed in 21 families, with 48 botanical species identified, and 27 individuals not identified. The five most important (importance value) families was Fabaceae/Papilionoideae, Apocynaceae, Vochysiaceae, Sapotaceae and Fabaceae/Caesalpinoideae. And the ten most important species was Pouteria ramiflora, Dalbergia miscolobium, Hancornia speciosa, Macherium opacum, Sclerolobium paniculatum var. subvelutinum, Qualea grandiflora, Aspidosperma tomentosum, Byrsonima pachyphylla, Vochysia thyrsoidea and Hymenaea stigonocarpa. The H' index was of 3.01; 2.72; 2.48 and 2.09 for "Arei\ue3o, Arei\ue3ozinho, Chapada de Latossolo and Tabuleiro", respectively. The Sij index indicated a small floristic similarity for all the combinations between the environments

    Expanding tropical forest monitoring into Dry Forests: The DRYFLOR protocol for permanent plots

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    This is the final version. Available on open access from Wiley via the DOI in this recordSocietal Impact Statement Understanding of tropical forests has been revolutionized by monitoring in permanent plots. Data from global plot networks have transformed our knowledge of forests’ diversity, function, contribution to global biogeochemical cycles, and sensitivity to climate change. Monitoring has thus far been concentrated in rain forests. Despite increasing appreciation of their threatened status, biodiversity, and importance to the global carbon cycle, monitoring in tropical dry forests is still in its infancy. We provide a protocol for permanent monitoring plots in tropical dry forests. Expanding monitoring into dry biomes is critical for overcoming the linked challenges of climate change, land use change, and the biodiversity crisis.Newton FundNatural Environment Research Council (NERC)Fundação de Amparo à Pesquisa do Estado de São PauloCYTE

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset

    Retinal nerve fiber layer thickness and cognitive ability in older people:the Lothian Birth Cohort 1936 study

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    BACKGROUND: This study aims to examine the relationship between the retinal nerve fiber layer (RNFL) thickness as measured by optical coherence tomography (OCT) and lifetime cognitive change in healthy older people. METHODS: In a narrow-age sample population from the Lothian Birth Cohort 1936 who were all aged approximately 72 years when tested, participants underwent RNFL measurements using OCT. General linear modeling was used to calculate the effect of RNFL thickness on three domains; general cognitive ability (g-factor), general processing speed (g-speed) and general memory ability (g-memory) using age at time of assessment and gender as co-variates. RESULTS: Of 105 participants, 96 completed OCT scans that were of suitable quality for assessment were analyzed. Using age and gender as covariates, we found only one significant association, between the inferior area RNFL thickness and g-speed (p = 0.049, η(2) = 0.045). Interestingly, when we included age 11 IQ as a covariate in addition to age and gender, there were several statistically significant associations (p = 0.029 to 0.048, η(2) = 0.00 to 0.059) in a negative direction; decreasing scores on measures of g-factor and g-speed were associated with increasing RNFL thickness (r = −0.229 to −0.243, p < 0.05). No significant associations were found between RNFL thickness and g-memory ability. When we considered the number of years of education as a covariate, we found no significant associations between the RNFL thickness and cognitive scores. CONCLUSIONS: In a community dwelling cohort of healthy older people, increased RNFL thickness appeared to be associated with lower general processing speed and lower general cognitive ability when age 11 IQ scores were included as a covariate
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