Characterization and Trends of Fine Particulate Matter (PM2.5) Fire Emissions in the Brazilian Cerrado during 2002–2017

This work is licensed under a Creative Commons Attribution 4.0 International License.Fire occurrence is a major disturbance in the Brazilian Cerrado, which is driven by both natural and anthropogenic activities. Despite increasing efforts for monitoring the Cerrado, a biome-scale study for quantifying and understanding the variability of fire emissions is still needed. We aimed at characterizing and finding trends in Particulate Matter with diameter less than 2.5 µm (PM2.5) fire emissions in the Brazilian Cerrado using the PREP-CHEM-SRC emissions preprocessing tool and Moderate Resolution Imaging Spectroradiometer (MODIS) active fires datasets for the 2002–2017 period. Our results showed that, on average, the Cerrado emitted 1.08 Tg year−1 of PM2.5 associated with fires, accounting for 25% and 15% of the PM2.5 fire emissions in Brazil and South America, respectively. Most of the PM2.5 fire emissions were concentrated in the end of the dry season (August, 0.224 Tg month−1 and September, 0.386 Tg month−1) and in the transitional month (October, 0.210 Tg month−1). Annually, 66% of the total emissions occurred over the savanna land cover; however, active fires that were detected in the evergreen broadleaf land cover tended to emit more than active fires occurring in the savanna land cover. Spatially, each 0.1° grid cell emitted, on average, 0.5 Mg km−2 year−1 of PM2.5 associated with fires, but the values can reach to 16.6 Mg km−2 year−1 in a single cell. Higher estimates of PM2.5 emissions associated with fires were mostly concentrated in the northern region, which is the current agricultural expansion frontier in this biome. When considering the entire Cerrado, we found an annual decreasing trend representing -1.78% of the annual average PM2.5 emitted from fires during the period analyzed, however, the grid cell analysis found annual trends representing ± 35% of the annual average PM2.5 fire emissions

ANÁLISE DE CRESCIMENTO DA MANCHA URBANA DO MUNICÍPIO DE FREDERICO WESTPHALEN, RS-BRASIL ATRAVÉS DE IMAGENS LANDSAT 5 TM

O estudo do crescimento urbano de um município possibilita a identificação e a análise de tendências quanto à expansão preferencial da mancha urbana. Essas informações auxiliam na definição de estratégias de planejamento para atender aos aspectos sociais, econômicos e ambientais. O objetivo deste estudo foi determinar o crescimento da mancha urbana do município de Frederico Westphalen - RS, no período de 1987 a 2011. Foram utilizadas nove imagens do satélite Landsat 5, sensor TM, de: 1987, 1990, 1993, 1996, 1999, 2002, 2005, 2008 e 2011.  As bandas centradas em 450, 550 e 660 nm foram restauradas pelo método IHS de 30 para 10 metros. Essas cenas foram registradas a partir de uma imagem ortorretificada  GeoCover 2000 utilizada como referência. Delimitou-se a área referente à mancha urbana do município, a qual foi vetorizada e sobreposta em todas as imagens. Foram realizadas classificações baseadas em procedimentos visuais (classificação manual) ao invés de processamento digital (automatizado) com o intuito de estimar o espaço ocupado pela mancha urbana em cada data. Os resultados permitiram estimar o crescimento da mancha urbana em intervalos de três anos e foram confrontados com dados demográficos do censo. A maior taxa de expansão foi verificada para o período entre 2008 e 2011. Entre os anos de 1987 e 2011 o crescimento verificado correspondeu a 295,23 ha, o que equivale a 109,05% de aumento em relação a 1987.  Em geral, a cidade de Frederico Westphalen apresentou uma expansão radial. Como esperado, os resultados do processo de mapeamento apresentaram uma concordância significativa com o crescimento da população urbana

Use of MODIS Sensor Images Combined with Reanalysis Products to Retrieve Net Radiation in Amazonia

In the Amazon region, the estimation of radiation fluxes through remote sensing techniques is hindered by the lack of ground measurements required as input in the models, as well as the difficulty to obtain cloud-free images. Here, we assess an approach to estimate net radiation (Rn) and its components under all-sky conditions for the Amazon region through the Surface Energy Balance Algorithm for Land (SEBAL) model utilizing only remote sensing and reanalysis data. The study period comprised six years, between January 2001–December 2006, and images from MODIS sensor aboard the Terra satellite and GLDAS reanalysis products were utilized. The estimates were evaluated with flux tower measurements within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. Comparison between estimates obtained by the proposed method and observations from LBA towers showed errors between 12.5% and 16.4% and 11.3% and 15.9% for instantaneous and daily Rn, respectively. Our approach was adequate to minimize the problem related to strong cloudiness over the region and allowed to map consistently the spatial distribution of net radiation components in Amazonia. We conclude that the integration of reanalysis products and satellite data, eliminating the need for surface measurements as input model, was a useful proposition for the spatialization of the radiation fluxes in the Amazon region, which may serve as input information needed by algorithms that aim to determine evapotranspiration, the most important component of the Amazon hydrological balance

Redução da esteatose em modelo de doença hepática alcoólica através da suplementação do probiótico Lactobacillus Rhamnosus GG

Pressure measurements are traditionally made using pressure taps connected to a transducer. These measurements are labor-intensive, expensive and only yield discrete values. Pressure-sensitive paint is a method of optically measuring the pressure across an entire model. Originally designed for use in transonic flow, pressure-sensitive paints are absolute pressure sensors. Therefore, application of pressure-sensitive paint to low-speed flow represents a significant challenge to researchers. This study investigates the surface pressure distribution around a U-bend of sharp curvature with three different inlet velocities: 29.7, 21.5 and 12.0ms-1. The absolute accuracy of the paint has been measured and compared with previously published literature and empirical relations. The paint was excited using two LED lamps, and full-field pressure maps have been gathered using a CCD camera. The absolute accuracy of the pressure measurements is ultimately limited by CCD shot noise, but is more commonly limited by the temperature-induced error and the microheterogeneity of the painted surface. © 2013 Elsevier Inc

Effects of tryptophan depletion and tryptophan loading on the affective response to high-dose CO2 challenge in healthy volunteers

It has been reported that in panic disorder (PD), tryptophan depletion enhances the vulnerability to experimentally induced panic, while the administration of serotonin precursors blunts the response to challenges. Using a high-dose carbon dioxide (CO2) challenge, we aimed to investigate the effects of acute tryptophan depletion (ATD) and acute tryptophan loading (ATL) on CO2-induced panic response in healthy volunteers. Eighteen healthy volunteers participated in a randomized, double-blind placebo-controlled study. Each subject received ATD, ATL, and a balanced condition (BAL) in separate days, and a double-breath 35% CO2 inhalation 4.5 h after treatment. Tryptophan (Trp) manipulations were obtained adding 0 g (ATD), 1.21 g (BAL), and 5.15 g (ATL) of l-tryptophan to a protein mixture lacking Trp. Assessments consisted of a visual analogue scale for affect (VAAS) and panic symptom list. A separate analysis on a sample of 55 subjects with a separate-group design has also been performed to study the relationship between plasma amino acid levels and subjective response to CO2. CO2-induced subjective distress and breathlessness were significantly lower after ATD compared to BAL and ATL (p <0.05). In the separate-group analysis, Delta VAAS scores were positively correlated to the ratio Trp:I LNAA pound after treatment (r = 0.39; p <0.05). The present results are in line with preclinical data indicating a role for the serotonergic system in promoting the aversive respiratory sensations to hypercapnic stimuli (Richerson, Nat Rev Neurosci 5(6):449-461, 2004). The differences observed in our study, compared to previous findings in PD patients, might depend on an altered serotonergic modulatory function in patients compared to healthy subjects

Building a Systematic Online Living Evidence Summary of COVID-19 Research

Throughout the global coronavirus pandemic, we have seen an unprecedented volume of COVID-19 researchpublications. This vast body of evidence continues to grow, making it difficult for research users to keep up with the pace of evolving research findings. To enable the synthesis of this evidence for timely use by researchers, policymakers, and other stakeholders, we developed an automated workflow to collect, categorise, and visualise the evidence from primary COVID-19 research studies. We trained a crowd of volunteer reviewers to annotate studies by relevance to COVID-19, study objectives, and methodological approaches. Using these human decisions, we are training machine learning classifiers and applying text-mining tools to continually categorise the findings and evaluate the quality of COVID-19 evidence

ANÁLISE DE CRESCIMENTO DA MANCHA URBANA DO MUNICÍPIO DE FREDERICO WESTPHALEN, RS-BRASIL ATRAVÉS DE IMAGENS LANDSAT 5 TM

O estudo do crescimento urbano de um município possibilita a identificação e a análise de tendências quanto à expansão preferencial da mancha urbana. Essas informações auxiliam na definição de estratégias de planejamento para atender aos aspectos sociais, econômicos e ambientais. O objetivo deste estudo foi determinar o crescimento da mancha urbana do município de Frederico Westphalen - RS, no período de 1987 a 2011. Foram utilizadas nove imagens do satélite Landsat 5, sensor TM, de: 1987, 1990, 1993, 1996, 1999, 2002, 2005, 2008 e 2011.  As bandas centradas em 450, 550 e 660 nm foram restauradas pelo método IHS de 30 para 10 metros. Essas cenas foram registradas a partir de uma imagem ortorretificada  GeoCover 2000 utilizada como referência. Delimitou-se a área referente à mancha urbana do município, a qual foi vetorizada e sobreposta em todas as imagens. Foram realizadas classificações baseadas em procedimentos visuais (classificação manual) ao invés de processamento digital (automatizado) com o intuito de estimar o espaço ocupado pela mancha urbana em cada data. Os resultados permitiram estimar o crescimento da mancha urbana em intervalos de três anos e foram confrontados com dados demográficos do censo. A maior taxa de expansão foi verificada para o período entre 2008 e 2011. Entre os anos de 1987 e 2011 o crescimento verificado correspondeu a 295,23 ha, o que equivale a 109,05% de aumento em relação a 1987.  Em geral, a cidade de Frederico Westphalen apresentou uma expansão radial. Como esperado, os resultados do processo de mapeamento apresentaram uma concordância significativa com o crescimento da população urbana