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Abstract In eastern sub-humid Bahia, Brazil, surface water stored in lined ponds is used to drip irrigate Sumatra tobacco plants grown under partial shading. This work, as part of a large evaporation study, aimed at monitoring, over two irrigation seasons (2015 and 2016), the water turbidity, the radiation balance (shortwave - SW and longwave - LW components), and the skin water temperature (Tw) with sensors deployed in a raft. The water turbidity was very low (around 2.6 NTU on average) due to filtration and reverse osmosis treatment of water prior to storage. Considering data from both seasons, the net SW radiation Snet was about 96% of incoming SW flux Sg. The daily net LW flux Lnet was consistently negative (-55.1 W/m2 average). The net all-wave radiation Rn corresponded to 77% of Snet. Four days were selected from both seasons to evaluate the effects of cloudiness on the SW and LW components. While Snet decreased with cloudiness due to solar radiation blockage, Lnet also decreased but due to increasing of downward LW radiation Latm with cloudiness. Rn also decreased with cloud cover. Based on the 2015 data, on average, daily Tw (26.1 °C) was higher than air temperature Ta (21.8 °C) due to near-surface absorption of solar radiation with Ta showing a much higher daily amplitude.

Abstract The albedo of a water surface and the energy available for evaporation are strongly correlated and studying such processes is of paramount importance for water security at farm and regional levels. In this paper, water albedo (αw) and net all-wave radiation (Rn) were analyzed after being measured above the surface of an artificially cleaned and low-turbidity water used for tobacco irrigation. It was observed that αw decreased as the sun elevation (θ) increased, especially for clear and near clear skies. The results showed that αw can be reasonably predicted with a power law model either in terms of θ or Sg (incoming solar radiation) across different cloud cover conditions. From this study, a mean daily albedo of 0.05 is recommended. Three approaches were considered for estimation of daily Rn. In the first, a linear regression model strongly fitted Rn data in terms of Sg solely. The second option based on the definition of Rn was [0.95Sg - Lnet(56)], where Lnet(56) is net longwave (LW) radiation as used in the FAO56 model for reference evapotranspiration estimation, and the third was [0.95Sg - Lnet(MLR)], where MLR stands for multiple linear regression. The disadvantages of approaches (1) and (3), based on regressions, is that they are constrained to the type of water stored in the farm and the climatic conditions of the region. The performance of approach (2), where Lnet(56) is a widely used model, was comparable to the others can potentially be improved with a site-specific calibration. All three approaches for estimating daily Rn proposed in this study can possibily be extended to clear water that did not go through any filtration process.

Introduction: Epicardial adipose tissue serves as a source of inflammatory cytokines and mediators. Cytokine storm is an important cause of morbidity and mortality in coronavirus disease 2019 (COVID-19). Objectives: To investigate the association between epicardial fat volume (EFV), inflammatory biomarkers and clinical severity of COVID-19. Methods: This retrospective study included 101 patients who were infected with COVID-19. Serum inflammatory biomarkers including C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin (PCT) and ferritin levels were measured. Computed tomography images were analyzed and semi-automated measurements for EFV were obtained. The primary composite endpoint was admission to the intensive care unit (ICU) or death. Results: The primary composite endpoint occurred in 25.1% (n=26) of patients (mean age 64.8±14.8 years, 14 male). A total of 10 patients died. EFV, CRP, PCT, ferritin and IL-6 levels were significantly higher in ICU patients. Moreover, a positive correlation was determined between EFV and CRP (r: 0.494, p102 cm3 were more likely to have severe complications. In multivariate logistic regression analysis, EFV independently predicted admission to the ICU at a significant level (OR: 1.02, 95% CI: 1.01-1.03, p=0.025). Conclusion: EFV and serum CRP, IL-6, PCT and ferritin levels can effectively assess disease severity and predict the outcome in patients with COVID-19. EFV is an independent predictor of admission to the ICU in hospitalized COVID-19 patients. Resumo: Introdução: O tecido adiposo epicárdico é fonte de citocinas inflamatórias e mediadores. A tempestade de citocinas é uma importante causa de morbilidade e mortalidade na doença coronavírus 2019 (COVID-19). Objetivos: Investigar a associação entre volume adiposo epicárdico (VAE), biomarcadores inflamatórios e gravidade clínica da COVID-19. Métodos: Este estudo retrospetivo incluiu 101 doentes infetados com COVID-19. Foram avaliados biomarcadores inflamatórios séricos, incluindo os níveis de proteína C-reativa (PCR), de interleucina-6 (IL-6), de procalcitonina (PCT) e de ferritina. Foram analisadas imagens de tomografia computorizada (TC) e foram obtidas medições semi-automáticas do VAE. O endpoint primário composto foi a admissão na unidade de cuidados intensivos (UCI) ou morte. Resultados: O endpoint primário ocorreu em 25,1% (n=26) dos doentes (idade média 64,8±14,8 anos, 14 homens). Um total de 10 doentes morreu. Os níveis de VAE, PCR, PCT, ferritina e IL-6 foram significativamente superiores nos doentes internados na UCI. Além disso, verificou-se uma correlação positiva entre o VAE e a PCR (r: 0,494, p102 cm3 tinham maior probabilidade de ter complicações graves. Conclusão: O VAE e os níveis séricos de PCR, IL-6, PCT e ferritina podem avaliar a gravidade da doença e prever o resultado em doentes com COVID-19. O VAE constitui um fator preditivo na admissão dos doentes hospitalizados com COVID-19 numa UCI.

JUSTIFICATIVA E OBJETIVOS: O objetivo deste estudo foi desenvolver uma técnica simples e prática para a cateterização crônica em canal peridural sacral de coelhos. MÉTODOS: O estudo incluiu dez coelhos com peso entre 2 e 2,5 kg. Após a anestesia e a analgesia, colocamos um cateter peridural através de uma incisão longitudinal de 2 cm na cauda acima da região do hiato sacral. Confirmamos a localização com a administração de lidocaína a 1% (nivelamento da perda sensorial e da função motora dos membros inferiores). O cateter foi introduzido através de um túnel subcutâneo até o pescoço, onde foi fixado. RESULTADOS: A implantação de cateter crônico peridural caudal foi bem-sucedida em todos os coelhos. Os cateteres permaneceram eficazmente no lugar por dez dias, sem intercorrências durante esse período. A localização do cateter foi reconfirmada por lidocaína a 1% no último dia. Após matar os animais, procedeu-se laminectomia para localização do cateter no espaço peridural. CONCLUSÕES: Há vários métodos de cateterização do espaço peridural em modelos animais na literatura. A cateterização do espaço peridural em coelhos pode ser feita através das vias atlanto-occipital, lombar ou caudal por amputação da cauda. As técnicas de cateterização intratecal e peridural descritas na literatura exigem perícia cirúrgica e conhecimento de procedimentos cirúrgicos, como laminectomia e amputação da cauda. A nossa técnica não requer grande habilidade cirúrgica, a integridade anatômica foi preservada e não houve mau posicionamento de cateter. Em conclusão, podemos sugerir que a nova técnica de cateterização peridural é simples, facilmente aplicável e pode ser usada em estudos experimentais de modelos animais.