2,427 research outputs found

    Changes in Climate and Land Use Over the Amazon Region: Current and Future Variability and Trends

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    This is the final version. Available on open access from Frontiers media via the DOI in this recordThis paper shows recent progress in our understanding of climate variability and trends in the Amazon region, and how these interact with land use change. The review includes an overview of up-to-date information on climate and hydrological variability, and on warming trends in Amazonia, which reached 0.6–0.7°C over the last 40 years, with 2016 as the warmest year since at least 1950 (0.9°C + 0.3°C). We focus on local and remote drivers of climate variability and change. We review the impacts of these drivers on the length of dry season, the role of the forest in climate and carbon cycles, the resilience of the forest, the risk of fires and biomass burning, and the potential “die back” of the Amazon forests if surpassing a “tipping point”. The role of the Amazon in moisture recycling and transport is also investigated, and a review of model development for climate change projections in the region is included. In sum, future sustainability of the Amazonian forests and its many services requires management strategies that consider the likelihood of multi-year droughts superimposed on a continued warming trend. Science has assembled enough knowledge to underline the global and regional importance of an intact Amazon region that can support policymaking and to keep this sensitive ecosystem functioning. This major challenge requires substantial resources and strategic cross-national planning, and a unique blend of expertise and capacities established in Amazon countries and from international collaboration. This also highlights the role of deforestation control in support of policy for mitigation options as established in the Paris Agreement of 2015.National Institute of Science and Technology for Climate ChangeFAPESPNational Coordination for High Level Education and Training (CAPES)Deutsche ForschungsgemeinschafNewton Fun

    Impacts of climate extremes in Brazil the development of a web platform for understanding long-term sustainability of ecosystems and human health in amazonia (pulse-Brazil)

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    This is the final version of the article. Available from the American Meteorological Society via the DOI in this record.This work was funded by the joint FAPESP 2011/51843-2 and NERC NE/J016276/1 International Opportunities Fund. PULSE-Brazil development is also funded by the FAPESP grant (2012/51876-0) under the Belmont Forum Cooperation Agreement. Marengo and Aragão thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for their Research Productivity Fellowship

    Lymphocyte Subpopulations in Sjögren’s Syndrome Are Distinct in Anti-SSA-Positive Patients and Related to Disease Activity

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    Objectives: Sjögren's syndrome (SjS) patients exhibit great phenotypical heterogeneity, reinforced by the positiveness of anti-SSA antibody. We aimed to evaluate lymphocyte subpopulations in SSA-positive (SSA+SjS) and SSA-negative (SSA-SjS) SjS patients, Sicca patients, and healthy controls (HC), and to investigate associations between lymphocyte subpopulations and disease activity in SjS. Methods: According to the fulfilment of the ACR/EULAR 2016 classification criteria, patients were included as SjS or as Sicca. HC were selected from the Ophthalmology outpatient clinic. Lymphocyte subpopulations were characterized by flow cytometry. Statistical analysis was performed with GraphPad PrismTM, with statistical significance concluded if p < 0.05. Results: We included 53 SjS patients (38 SSA+ and 15 SSA-), 72 Sicca, and 24 HC. SSA+SjS patients presented increased IL-21+CD4+ and CD8+ T cells compared to Sicca and HC, whereas compared to SSA-SjS patients, only IL-21+CD4+ T cell percentages were increased and Tfh17 percentages and numbers were decreased. Compared to Sicca and HC, SSA+SjS patients had higher levels of CD24HiCD38Hi B cells, naïve B cells, and IgM-/+CD38++ plasmablasts, and lower levels of memory B cells, including CD24HiCD27+ B cells. SSA+SjS patients with clinically active disease had positive correlations between ESSDAI and IL-21+CD4+ (p = 0.038, r = 0.456) and IL-21+CD8+ T cells (p = 0.046, r = 0.451). Conclusions: In SjS, a distinct lymphocyte subset distribution profile seems to be associated with positive anti-SSA. Moreover, the association between ESSDAI and IL-21+CD4+ and IL-21+CD8+ (follicular) T cells in SSA+SjS patients suggests the involvement of these cells in disease pathogenesis and activity, and possibly their utility for the prognosis and assessment of response to therapy. Key Points • SSA+SjS patients have a pronounced naïve/memory B cell imbalance. • SSA+SjS patients have more active disease associated with IL-21+CD4+ and IL-21+CD8+ follicular T cell expansion. • IL-21+CD4+ and IL-21+CD8+ T cell quantification may be useful for the prognosis and assessment of response to therapy.info:eu-repo/semantics/publishedVersio

    Assessment of rainfall variability and future change in Brazil across multiple timescales

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordRainfall variability change under global warming is a crucial issue that may have a substantial impact on society and the environment, as it can directly impact biodiversity, agriculture, and water resources. Observed precipitation trends and climate change projections over Brazil indicate that many sectors of society are potentially highly vulnerable to the impacts of climate change. The purpose of this study is to assess model projections of the change in rainfall variability at various temporal scales over sub‐regions of Brazil. For this, daily data from 30 CMIP5 models for historical (1900–2005) and future (2050–2100) experiments under a high‐emission scenario are used. We assess the change in precipitation variability, applying a band‐pass filter to isolate variability on daily, weekly, monthly, intra‐seasonal, and El Nino Southern Oscillation (ENSO) time scales. For historical climate, simulated precipitation is evaluated against observations to establish model reliability. The results show that models largely agree on increases in variability on all timescales in all sub‐regions, except on ENSO timescales where models do not agree on the sign of future change. Brazil will experience more rainfall variability in the future that is, drier or more frequent dry periods and wetter wet periods on daily, weekly, monthly, and intra‐seasonal timescales, even in sub‐regions where future changes in mean rainfall are currently uncertain. This may provide useful information for climate change adaptation across, for example, the agriculture and water resource sectors in Brazil.DFG/FAPES

    Association Between Memory B-Cells and Clinical and Immunological Features of Primary Sjögren’s Syndrome and Sicca Patients

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    B-cells play a pivotal role in primary Sjögren's syndrome (pSS) pathogenesis. We aim to (1) evaluate the distribution of B-lymphocyte subpopulations in pSS and Sicca patients, (2) establish cut-off points that discriminate pSS from controls, (3) evaluate the association between memory B-cells and phenotypic features in pSS. We included 57 pSS patients, 68 Sicca and 24 healthy controls. Circulating B-cells were characterized by flow cytometry as naïve and memory subsets and classified from Bm1 to Bm5. Compared to controls, pSS patients had lower percentages (29.5 vs 44.4%) and absolute numbers (47 vs 106 cells/µl) of memory B-cells. Through ROC curves, a cut-off of ≤ 58 total memory B-cells/µl yielded a specificity of 0.88 and a sensitivity of 0.60 for pSS, and was met by 59.6% of pSS patients, 38.8% of Sicca and 12.5% of controls. A cut-off of < 23.5 Switched-memory B-cells/µl yielded a specificity of 0.88 and a sensitivity of 0.54 and was met by 54.4% of pSS patients, 37.3% of Sicca and 12.5% of controls. In pSS, lower total memory B-cells count was associated with longer disease duration (14.3 vs 8.1 years, p = 0.006) and more active disease profile, as evaluated by the European League Against Rheumatism (EULAR) Sjögren's Syndrome Disease Activity Index (ESSDAI) (3.1 vs 1.4, p = 0.043). Decreased numbers of memory B-cells clearly discriminated pSS from controls and can also have prognostic value. It remains to be clarified whether Sicca patients with decreased memory B-cells represent pSS and if B-cell profiling could help in the diagnosis of pSS.info:eu-repo/semantics/publishedVersio

    Lessons on direct seeding to restore Neotropical savanna

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    Made available in DSpace on 2019-08-20T00:37:11Z (GMT). No. of bitstreams: 1 1s2.0S0925857419302538main.pdf: 860572 bytes, checksum: 311484784c0c84dd5129dd180114070c (MD5) Previous issue date: 2019bitstream/item/201069/1/1-s2.0-S0925857419302538-main.pd

    Added value of lymphocyte subpopulations in the classification of Sjögren's syndrome

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    Sjögren's Syndrome (SjS) is a chronic systemic immune-mediated inflammatory disease characterized by lymphocytic infiltration and consequent lesion of exocrine glands. SjS diagnosis and classification remains a challenge, especially at SjS onset, when patients may have milder phenotypes of the disease or uncommon presentations. New biomarkers are needed for the classification of SjS, thus, we aimed to evaluate the added-value of lymphocyte subpopulations in discriminating SjS and non-Sjögren Sicca patients. Lymphocyte subsets from 62 SjS and 63 Sicca patients were characterized by flow cytometry. The 2002 AECG and the 2016 ACR/EULAR SjS classification criteria were compared with clinical diagnosis. The added discriminative ability of joining lymphocytic populations to classification criteria was assessed by the area under the Receiver-Operating-Characteristic Curve (AUC). Considering clinical diagnosis as the gold-standard, we obtained an AUC = 0.952 (95% CI: 0.916-0.989) for AECG and an AUC = 0.921 (95% CI: 0.875-0.966) for ACR/EULAR criteria. Adding Tfh and Bm1 subsets to AECG criteria, performance increased, attaining an AUC = 0.985 (95% CI: 0.968-1.000) (p = 0.021). Th1/Breg-like CD24hiCD27+ and switched-memory B-cells maximized the AUC of ACR/EULAR criteria to 0.953 (95% CI: 0.916-0.990) (p = 0.043). Our exploratory study supports the potential use of lymphocyte subpopulations, such as unswitched memory B cells, to improve the performance of classification criteria, since their discriminative ability increases when specific subsets are added to the criteria.info:eu-repo/semantics/publishedVersio

    Cell walls of the dimorphic fungal pathogens Sporothrix schenckii and Sporothrix brasiliensis exhibit bilaminate structures and sloughing of extensive and intact layers

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    This work was supported by the Fundação Carlos Chagas de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), grants E-26/202.974/2015 and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), grants 229755/2013-5, Brazil. LMLB is a senior research fellow of CNPq and Faperj. NG acknowledged support from the Wellcome Trust (Trust (097377, 101873, 200208) and MRC Centre for Medical Mycology (MR/N006364/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
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