504 research outputs found

    Decrease of deforestation in Protected Areas of Madagascar during the Covid-19 years

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    Deforestation poses a significant threat to global biodiversity and ecosystem services. This study focuses on estimating the deforestation within Protected Areas (PAs) in Madagascar over a 21-year period from 2001 to 2022. A novel methodology utilizing remote sensing data and specific thresholds of tree canopy density is employed to estimate annual deforestation rates and identify trends and patterns within PAs. The analysis reveals significant deforestation in the PA network over the last decade, particularly in 2014, 2017, 2018, and 2019. Notably, the lowest annual deforestation rates were estimated during the Covid-19 years of 2020 (0.66%), 2021 (0.62%), and the subsequent year in 2022 (0.67%) when considering the entire network of 103 PAs with natural forests from 2013 to 2022.   Résumé La déforestation constitue une menace importante pour la biodiversité mondiale et les services écosystémiques. Cette étude se concentre sur l'évaluation de l'efficacité des aires protégées (AP) pour lutter contre la déforestation à Madagascar sur une période de 21 ans, de 2001 à 2022. Une méthodologie novatrice utilisant des données de télédétection et des seuils spécifiques de densité du couvert arboré est employée pour estimer les taux annuels de déforestation et identifier les tendances et les modèles au sein des AP. Au cours de la dernière décennie, l'analyse révèle une déforestation significative dans le réseau des AP au cours de certaines années, notamment en 2014, 2017, 2018 et 2019. En revanche, il est intéressant de noter qu'entre 2013 et 2022, les taux annuels de déforestation les plus bas ont été estimés pendant les années de Covid-19 en 2020 (0,66 %), 2021 (0,62 %) et l'année suivante en 2022 (0,67 %) sur l’ensemble du réseau des 103 AP avec des forêts naturelles

    Nitric oxide synthase 2A (NOS2A) polymorphisms are not associated with invasive pneumococcal disease

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    <p>Abstract</p> <p>Background</p> <p><it>Streptococcus pneumoniae </it>(pneumococcus) is responsible for over one million deaths per year, with young children, the elderly and immunocompromised individuals being most at risk. Approximately half of East African children have been reported to be asymptomatic carriers of pneumococcus with invasive infection occurring after the disruption of the respiratory membrane which is believed to be caused by the host immune response. Racial incidence of invasive pneumococcal disease (IPD) is higher in certain populations even after adjusting for environmental factors suggesting a genetic component to disease susceptibility. The nitric oxide synthase 2A (NOS2A) gene is responsible for the production of nitric oxide under pathological conditions including host defence against bacterial infection. Nitric oxide is a modulator of apoptotic and inflammatory cascades and endothelial permeability. We hypothesised that genetic variants within this gene may predispose to disease risk and survival.</p> <p>Methods</p> <p>A cohort of 299 children with IPD (221 meningitis, 41 pneumonia and 37 with bacteraemia) and 931 age matched controls from Malawi were used in this study. We investigated nine haplotype tagging single nucleotide polymorphisms within the NOS2A gene and compared the presence or absence of the minor alleles in cases and controls and survivors and non-survivors within the cases.</p> <p>Results</p> <p>We observed no significant associations between cases and controls or with survival in either all IPD cases or in the separate analysis of meningitis cases. A near significant association was obtained for the comparison of rs8078340 in cases and controls (p-value, 0.078). However, results were unadjusted for multiple testing.</p> <p>Conclusion</p> <p>Our results suggest that polymorphic variation within the NOS2A gene does not influence invasive pneumococcal disease susceptibility or survival.</p

    Partial silicification of chalk fossils from the Chilterns

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    RESP-624

    Recurrent bridgehead effects accelerate global alien ant spread.

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    Biological invasions are a major threat to biological diversity, agriculture, and human health. To predict and prevent new invasions, it is crucial to develop a better understanding of the drivers of the invasion process. The analysis of 4,533 border interception events revealed that at least 51 different alien ant species were intercepted at US ports over a period of 70 years (1914-1984), and 45 alien species were intercepted entering New Zealand over a period of 68 years (1955-2013). Most of the interceptions did not originate from species' native ranges but instead came from invaded areas. In the United States, 75.7% of the interceptions came from a country where the intercepted ant species had been previously introduced. In New Zealand, this value was even higher, at 87.8%. There was an overrepresentation of interceptions from nearby locations (Latin America for species intercepted in the United States and Oceania for species intercepted in New Zealand). The probability of a species' successful establishment in both the United States and New Zealand was positively related to the number of interceptions of the species in these countries. Moreover, species that have spread to more continents are also more likely to be intercepted and to make secondary introductions. This creates a positive feedback loop between the introduction and establishment stages of the invasion process, in which initial establishments promote secondary introductions. Overall, these results reveal that secondary introductions act as a critical driver of increasing global rates of invasions

    In adult onset myositis, the presence of interstitial lung disease and myositis specific/associated antibodies are governed by HLA class II haplotype, rather than by myositis subtype

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    The aim of this study was to investigate HLA class II associations in polymyositis (PM) and dermatomyositis (DM), and to determine how these associations influence clinical and serological differences. DNA samples were obtained from 225 UK Caucasian idiopathic inflammatory myopathy patients (PM = 117, DM = 108) and compared with 537 randomly selected UK Caucasian controls. All cases had also been assessed for the presence of related malignancy and interstitial lung disease (ILD), and a number of myositis-specific/myositis-associated antibodies (MSAs/MAAs). Subjects were genotyped for HLA-DRB1, DQA1 and DQB1. HLA-DRB1*03, DQA1*05 and DQB1*02 were associated with an increased risk for both PM and DM. The HLA-DRB1*03-DQA1*05-DQB1*02 haplotype demonstrated strong association with ILD, irrespective of myositis subtype or presence of anti-aminoacyl-transfer RNA synthetase antibodies. The HLA-DRB1*07-DQA1*02-DQB1*02 haplotype was associated with risk for anti-Mi-2 antibodies, and discriminated PM from DM (odds ratio 0.3, 95% confidence interval 0.1–0.6), even in anti-Mi-2 negative patients. Other MSA/MAAs showed specific associations with other HLA class II haplotypes, irrespective of myositis subtype. There were no genotype, haplotype or serological associations with malignancy. The HLA-DRB1*03-DQA1*05-DQB1*02 haplotype associations appear to not only govern disease susceptibility in Caucasian PM/DM patients, but also phenotypic features common to PM/DM. Though strongly associated with anti-Mi-2 antibodies, the HLA-DRB1*07-DQA1*02-DQB1*02 haplotype shows differential associations with PM/DM disease susceptibility. In conclusion, these findings support the notion that myositis patients with differing myositis serology have different immunogenetic profiles, and that these profiles may define specific myositis subtypes

    Functional gene group analysis indicates no role for heterotrimeric G proteins in cognitive ability

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    Previous functional gene group analyses implicated common single nucleotide polymorphisms (SNPs) in heterotrimeric G protein coding genes as being associated with differences in human intelligence. Here, we sought to replicate this finding using five independent cohorts of older adults including current IQ and childhood IQ, and using both gene- and SNP-based analytic strategies. No significant associations were found between variation in heterotrimeric G protein genes and intelligence in any cohort at either of the two time points. These results indicate that, whereas G protein systems are important in cognition, common genetic variation in these genes is unlikely to be a substantial influence on human intelligence differences
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