13 research outputs found

    Patterns and drivers of evapotranspiration in South American wetlands

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    Evapotranspiration (ET) is a key process linking surface and atmospheric energy budgets, yet its drivers and patterns across wetlandscapes are poorly understood worldwide. Here we assess the ET dynamics in 12 wetland complexes across South America, revealing major differences under temperate, tropical, and equatorial climates. While net radiation is a dominant driver of ET seasonality in most environments, flooding also contributes strongly to ET in tropical and equatorial wetlands, especially in meeting the evaporative demand. Moreover, significant water losses through wetlands and ET differences between wetlands and uplands occur in temperate, more water-limited environments and in highly flooded areas such as the Pantanal, where slow river flood propagation drives the ET dynamics. Finally, floodplain forests produce the greatest ET in all environments except the Amazon River floodplains, where upland forests sustain high rates year round. Our findings highlight the unique hydrological functioning and ecosystem services provided by wetlands on a continental scale

    Estimating of gross primary production in an Amazon-Cerrado transitional forest using MODIS and Landsat imagery

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    The acceleration of the anthropogenic activity has increased the atmospheric carbon concentration, which causes changes in regional climate. The Gross Primary Production (GPP) is an important variable in the global carbon cycle studies, since it defines the atmospheric carbon extraction rate from terrestrial ecosystems. The objective of this study was to estimate the GPP of the Amazon-Cerrado Transitional Forest by the Vegetation Photosynthesis Model (VPM) using local meteorological data and remote sensing data from MODIS and Landsat 5 TM reflectance from 2005 to 2008. The GPP was estimated using Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) calculated by MODIS and Landsat 5 TM images. The GPP estimates were compared with measurements in a flux tower by eddy covariance. The GPP measured in the tower was consistent with higher values during the wet season and there was a trend to increase from 2005 to 2008. The GPP estimated by VPM showed the same increasing trend observed in measured GPP and had high correlation and Willmott's coefficient and low error metrics in comparison to measured GPP. These results indicated high potential of the Landsat 5 TM images to estimate the GPP of Amazon-Cerrado Transitional Forest by VPM

    Antileishmanial activity of lapachol analogues

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    The antileishmanial activity of lapachol, isolapachol, and dihydrolapachol, along with soluble derivatives (potassium salt) and acetate was obtained. All the compounds were assayed against metacyclic promastigotes of two different species of Leishmania associated to tegumentar leishmaniasis: L. amazonensis and L. braziliensis. All compounds presented significant activity, being isolapachol acetate the most active against promastigotes, with IC50/24h = 1.6 ± 0.0 µg/ml and 3.4 ± 0.5 µg/ml for, respectively, L. amazonensis and L. braziliensis. This compound was also assayed in vivo against L. amazonensis and showed to be active. Its toxicity in vitro was also established, and at concentration similar to the IC50, no toxicity was evidenced. In all experiments, pentamidine isethionate was used as a reference drug. The present results reinforce the potential use of substituted hydroxyquinones and derivatives as promising antileishmanial drugs and suggest a continuing study within this class of compounds

    Assessment of Remote Sensing and Re-Analysis Estimates of Regional Precipitation over Mato Grosso, Brazil

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    The spatial and temporal distribution of precipitation is of great importance for the rain-fed agricultural production and the socioeconomics of Mato Grosso (MT), Brazil. MT has a sparse network of ground rain gauges that limits the effective use of precipitation information for sustainable agricultural production and water resources in the region. Several gridded precipitation products from remote sensing and reanalysis of land surface models are currently available that can enhance the use of such information. However, these products are available at different spatial and temporal resolutions which add some challenges to stakeholders (users) to identify their appropriateness for specific applications (e.g., irrigation requirements, length of growing season, and drought monitoring). Thus, it is necessary to provide an assessment of the reliability of these precipitation estimates. The objective of this work was to compare regional precipitation estimates over MT as provided by the Global Land Data Assimilation (GLDAS), Modern-Era Retrospective Analysis for Research and Applications (MERRA), Tropical Rainfall Measurement Mission (TRMM), Global Precipitation Measurement (GPM), and the Global Precipitation Climatology Project (GPCP) with ground-based measurements. The comparison was conducted for the 2000–2018 period at eleven ground-based weather stations that covered different climate zones in MT using daily, monthly, and annual temporal resolutions. The comparison used the Pearson correlation index–r, Willmott index–d, root mean square error—RMSE, and the Wilks methods. The results showed GPM and GLDAS estimates did not differ significantly with the measured daily, monthly, and annual precipitation. TRMM estimates slightly overestimated daily precipitation by about 4.7% but did not show significant difference on the monthly and annual scales when compared with local measurements. The GPCP underestimated annual precipitation by about 7.1%. MERRA underestimated daily, monthly, and annual precipitation by about 22.9% on average. In general, all products satisfactorily estimated monthly precipitation, and most of them satisfactorily estimated annual precipitation; however, they showed low accuracy when estimating daily precipitation. The TRMM, GPM, GPCP, and GLDAS estimates had the highest performance, from high to low, while MERRA showed the lowest performance. The findings of this study can be used to support the decision-making process in the region in application related to water resources management, sustainability of agriculture production, and drought management

    Instituto Nacional de Ciência e Tecnologia em Medicina Translacional (INCT-TM): abordagens metodológicas National Science and Technology Institute for Translational Medicine (INCT-TM): advancing the field of translational medicine and mental health

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    OBJETIVO: Medicina translacional pode ser descrita como a aplicação integrada de ferramentas farmacológicas inovadoras, biomarcadores, métodos e tecnologias clínicas e delineamentos de pesquisa para aumentar o conhecimento a respeito das doenças. A pesquisa translacional oferece uma oportunidade para aplicar os achados de pesquisa básica na clínica cotidiana. O Instituto Nacional de Ciência e Tecnologia - Medicina Translacional foi criado com seis centros (Universidade Federal do Rio Grande do Sul, Universidade de São Paulo-Ribeirão Preto, Universidade Federal do Rio de Janeiro, Pontifícia Universidade Católica do Rio Grande do Sul, Universidade Estadual de Santa Catarina e uma core facility que serve a todos os centros). Os objetivos deste projeto são divididos em quatro dimensões: institucional, pesquisa, formação de recursos humanos e transferência de tecnologia para a comunidade e setor produtivo. MÉTODO: Neste artigo, são apresentadas algumas das estratégias utilizadas para atingir os objetivos do Instituto Nacional de Ciência e Tecnologia - Medicina Translacional: 1) Desenvolvimento de modelos animais para o transtorno bipolar; 2) Estratégias de investigação neurocomportamental e disfunções cognitivas dos transtornos cerebrais; 3) Modelos experimentais de funcionamento cerebral e comportamento, proliferação celular e câncer; 4)Teste de Simulação de Falar em Público e 5) Realidade Virtual para indução de Pânico e Agorafobia. CONCLUSÃO: O Instituto Nacional de Ciência e Tecnologia - Medicina Translacional possui como foco principal o desenvolvimento de metodologias mais úteis para aumentar a aplicabilidade dos conhecimentos da pesquisa básica em medicina.<br>OBJECTIVE: Translational medicine has been described as the integrated application of innovative pharmacology tools, biomarkers, clinical methods, clinical technologies and study designs to improve the understanding of medical disorders. In medicine, translational research offers an opportunity for applying the findings obtained from basic research to every-day clinical applications. The National Science and Technology Institute for Translational Medicine is comprised of six member institutions (Universidade Federal do Rio Grande do Sul, Universidade de São Paulo-Ribeirão Preto, Universidade Federal do Rio de Janeiro, Pontifícia Universidade Católica do Rio Grande do Sul, Universidade Estadual de Santa Catarina and a core facility that serves all centers). The objectives of the project are divided into four areas: Institutional, Research, Human Resources and Technology for the Community and Productive Sector. METHOD: In this manuscript, we describe some of the approaches used to attain the main objectives of the National Science and Technology Institute for Translational Medicine, which include the development of 1) animal models for bipolar disorder; 2) strategies to investigate neurobehavioral function and cognitive dysfunction associated with brain disorders; 3) experimental models of brain function and behavior, neuropsychiatric disorders, cell proliferation, and cancer; 4) Simulated Public Speaking and 5) Virtual reality simulation for inducing panic disorder and agoraphobia. CONCLUSION: The main focus of the National Science and Technology Institute for Translational Medicine is the development of more useful methods that allow for a better application of basic research-based knowledge to the medical field
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