Hematological problems are associated with Coronavirus disease 2019 (COVID-19). Respiratory impairment is the higher point studied, although without experimental studies related to the oxygen transport performed by erythrocytes. Therefore, we decided to investigate if erythrocytes from COVID-19 patients have their functionality changed. The case-control study included hospitalized patients with a positive real-time polymerase chain reaction (RT-PCR) result admitted to University Hospital. Volunteers (negative RT-PCR results) were recruited as a control group. Thus, we assessed different erythrocytes parameters, oxidative stress markers, and biophysical studies using whole blood and isolated hemoglobin. We found a decrease of 51% in oxygen uptake and reduced antioxidant enzyme activity in COVID-19 patients compared to controls. Raman spectrometry showed structural changes in the hemoglobin and lipids of the erythrocytes from COVID-19 patients; thus, these results were consolidated with an increase in Young’s modulus in erythrocytes followed by morphology changes. Besides, isolated hemoglobin from COVID-19 patients has a distinct interaction profile using a ligand model compared to the control. COVID-19 leads to structural, functional, and morphological damage to human erythrocytes. Our data showed structural and molecular changes and induction of oxidative stress in erythrocytes by COVID-19, a new perspective on the contribution of erythrocytes to a respiratory commitment in COVID-19.

RESUMO Objetivou-se, com este estudo, determinar as curvas de secagem dos rizomas de açafrão da terra em diferentes temperaturas, ajustar modelos de regressão não linear ao processo, em diversas condições de ar, bem como determinar o coeficiente de difusão efetiva e obter a energia de ativação. Os rizomas de açafrão da terra foram coletados com o auxílio de uma enxada e manualmente, de forma aleatória, no município de Rio Verde, GO. Em seguida, foram selecionados, medidos, higienizados e submetidos ao fatiamento com 2,63 ± 0,1 mm de espessura. Os rizomas foram submetidos a secagem em estufa com ventilação de ar forçada nas temperaturas de 45, 55, 65 e 75 °C. O tempo de secagem foi de 18; 14; 10 e 9 horas, respectivamente, para as temperaturas de 45, 55, 65 e 75 °C. À medida que a temperatura aumentou, o tempo de secagem diminuiu e, consequentemente, o teor de água final de equilíbrio também diminui, uma vez que o aumento da temperatura facilita o processo de secagem, por diminuir a energia necessária para remover moléculas de água ligadas ao produto. Entre os modelos ajustados, o de Midilli foi o que melhor se ajustou aos dados nas diferentes condições do ar de secagem. O coeficiente de difusão efetiva aumentou com a elevação da temperatura, com valores de 9,17 × 10-11, 13,33 × 10-11, 20,09 × 10-11 e 35,89 × 10-11 m2 s-1 para as temperaturas de 45, 55, 65 e 75 °C, respectivamente, e a energia de ativação para a difusão líquida na secagem foi de 21,186 kJ mol-1.

ABSTRACT This study aimed to determine drying curves of land saffron (Curcuma longa L.) rhizomes at different temperatures and ventilation conditions to adjust non-linear regression models, and to calculate effective diffusion coefficients and activation energies. Saffron rhizomes were randomly collected in natura with a hoe from the soil in Rio Verde, Goiás, Brazil. They were subsequently sized, sanitized, and sliced into 2.63 ± 0.1 mm thick sections. Rhizomes were dried in an oven with forced air ventilation at 45, 55, 65 and 75 °C for 18, 14, 10 and 9 hours, respectively. As the temperature increased, drying time was reduced. Consequently, moisture content also decreased, facilitating the drying process by decreasing the energy required to remove water molecules. Among the analyzed models, the Midilli model was best adjusted to the data under different drying air conditions. Effective diffusion coefficients (D) were 9.17 × 10-11, 13.33 × 10-11, 20.09 × 10-11, and 35.89 × 10-11 m2 s-1 at 45, 55, 65 and 75 °C, respectively, increasing with higher temperatures. Activation energy for liquid diffusion during drying was 21.186 kJ mol-1.

RESUMO Com este trabalho objetivou-se definir áreas potenciais de estabelecimento da monilíase do cacaueiro no Estado da Bahia, por meio da lógica fuzzy, com base em séries históricas de temperatura e umidade relativa do ar, disponíveis para 519 pontos de medição distribuídos no Estado da Bahia. Os dados foram submetidos inicialmente a uma análise estatística descritiva. A variabilidade espacial foi determinada através de análise geoestatística, seguida de interpolações para mapear a estrutura da dependência espaço-temporal do fenômeno. Para modelar o risco climático de estabelecimento da doença foram realizadas simulações de classificação contínua, pixel-a-pixel, das representações das variáveis, utilizando o mapeamento fuzzy. Aos dados de temperatura, aplicou-se o modelo fuzzy exponencial, enquanto que aos dados de umidade relativa do ar, o modelo utilizado foi o linear. As definições de áreas potenciais foram realizadas para cada mês, utilizando a informação conjunta das pertinências da temperatura e da umidade relativa do ar. Os modelos fuzzy utilizados permitiram modelar o risco climático de estabelecimento da monilíase no Estado da Bahia. A maior extensão do Estado da Bahia tem riscos elevados para o desenvolvimento da doença, o que exige medidas mitigadoras para evitar a introdução e disseminação do patógeno.

ABSTRACT This work aimed to determine potential areas for the establishment of cocoa moniliasis in Bahia state, Brazil, by means of fuzzy logic, based on historical datasets of temperature and air relative humidity, available for 519 measurement points distributed throughout the state of Bahia. The data were initially submitted to a descriptive statistical analysis. The spatial variability was determined through geostatistical analysis, followed by interpolation to map the spatial-temporal structure dependence of the phenomenon. Simulations of continuous pixel-to-pixel classification of variables were performed using fuzzy mapping to model the climatic risk of disease establishment. The exponential fuzzy model was applied to temperature data, while the linear model was used for air relative humidity data. The potential areas were defined for each month, using data of temperature and air relative humidity. The fuzzy models used allowed for modeling of the climatic risk of cocoa moniliasis establishment. A large area of the state is at high risk of disease, thus requiring mitigating measures to avoid the pathogen’s introduction and dissemination.

RESUMO A distribuição das tensões provocadas por rodados das máquinas agrícolas é dependente da carga da roda e da pressão interna do pneu, bem como das condições do solo. O objetivo do presente trabalho consistiu em avaliar numericamente a distribuição dos deslocamentos e das tensões atuantes em um solo coletado no Estado do Ceará, provocada pela passagem de um trator agrícola. O peso individual do pneu traseiro (dimensões 18.4-34 R1) em que foi medida a área de contato do pneu com o solo era de 17,1 kN. Nas análises numéricas, baseadas no método dos Elementos Finitos, foram considerados diferentes valores da pressão interna do pneu (96,5 kPa, 124,0 kPa, 151,0 kPa e 179,0 kPa) com suas respectivas áreas de contato (0,2256 m2, 0,1660 m2, 0,1522 m2 e 0,1393 m2). A partir dos resultados obtidos, verificou-se que as tensões verticais encontradas na superfície do solo foram aproximadamente iguais às pressões de inflação dos pneus. A menor pressão provocou a menor tensão no solo, demonstrando a importância da redução das pressões na diminuição da compactação do solo até profundidades de 0,30 m. As maiores pressões causaram as maiores deformações no solo provocadas pela diminuição da área de contato pneu/solo. Ficou evidente neste estudo que é necessário buscar soluções para reduzir as pressões de trabalho de forma a causar menor compactação superficial do solo devido às tensões verticais e horizontais.

ABSTRACT The distribution of tensions caused by agricultural machinery depends on wheel load and inner tire pressure, as well as soil conditions. This study aimed to evaluate numerically displacements and tensions caused by tractor traffic on soil from the state of Ceará, Brazil. The rear tire weight (size 18.4-34 R1) on its contact area with the soil was 17.1 kN. Different inner pressures were considered in the numerical analysis based on the method of Finite Elements (96.5 kPa, 124.0 kPa, 151.0 kPa and 179.0 kPa), with their respective contact areas (0.2256 m2, 0 .1660 m2, 0.1522 m2 and 0.1393 m2). Our findings showed that vertical tensions on soil surface were nearly equal to tire inflation pressures. The lower pressure promoted less tension on the soil, showing that pressure reduction is necessary for further decreases on soil compaction up to a depth of 0.30 m. We also concluded that is essential to seek for solutions to reduce operating pressures, in order to decrease surface soil compaction derived from vertical and horizontal tensions.

Background: Physical exercise may modify biologic stress responses. Objective: To investigate the impact of exercise training on vascular alterations induced by acute stress, focusing on nitric oxide and cyclooxygenase pathways. Method: Wistar rats were separated into: sedentary, trained (60-min swimming, 5 days/week during 8 weeks, carrying a 5% body-weight load), stressed (2 h-immobilization), and trained/stressed. Response curves for noradrenaline, in the absence and presence of L-NAME or indomethacin, were obtained in intact and denuded aortas (n=7-10). Results: None of the procedures altered the denuded aorta reactivity. Intact aortas from stressed, trained, and trained/stressed rats showed similar reduction in noradrenaline maximal responses (sedentary 3.54±0.15, stressed 2.80±0.10*, trained 2.82±0.11*, trained/stressed 2.97± 0.21*, *P<0.05 relate to sedentary). Endothelium removal and L-NAME abolished this hyporeactivity in all experimental groups, except in trained/stressed rats that showed a partial aorta reactivity recovery in L-NAME presence (L-NAME: sedentary 5.23±0,26#, stressed 5.55±0.38#, trained 5.28±0.30#, trained/stressed 4.42±0.41, #P<0.05 related to trained/stressed). Indomethacin determined a decrease in sensitivity (EC50) in intact aortas of trained rats without abolishing the aortal hyporeactivity in trained, stressed, and trained/stressed rats. Conclusions: Exercise-induced vascular adaptive response involved an increase in endothelial vasodilator prostaglandins and nitric oxide. Stress-induced vascular adaptive response involved an increase in endothelial nitric oxide. Beside the involvement of the endothelial nitric oxide pathway, the vascular response of trained/stressed rats involved an additional mechanism yet to be elucidated. These findings advance on the understanding of the vascular processes after exercise and stress alone and in combination.

Neste trabalho objetivou-se manter a qualidade e aumentar o tempo de prateleira durante a pós-colheita de bananas 'Prata-Anã' e se avaliou a eficiência do armazenamento refrigerado (AR) e da atmosfera modificada (AM) pelo uso de embalagens plásticas de polietileno de baixa densidade (PEBD), do vácuo e da utilização de sachê adsorvedor de etileno. Os tratamentos foram: T1: Controle (sem embalagem, sistema de adsorção de etileno e sem vácuo); T2: Embalagem de polietileno de baixa densidade (PEBD); T3: PEBD + adsorvedor de etileno; T4: PEBD + vácuo e T5: PEBD + adsorvedor de etileno + vácuo. As análises foram realizadas em intervalos de 5 dias após a colheita, até 35 dias de AR. Verificou-se que os frutos submetidos à embalagem de PEBD apresentaram as menores áreas de lesão na casca, as menores concentrações de etileno, os menores incrementos de acidez titulável (AT) e comportamento normal/manutenção dos valores de pH o que, possivelmente, proporcionou os maiores teores de açúcares totais e redutores ao final do período experimental; concluiu-se,então, que a combinação do uso da embalagem de PEBD com os sachês adsorvedores de etileno resultou no retardamento do processo de maturação dos frutos de banana 'Prata-Anã' proporcionando, comercialmente, a extensão da vida útil dos frutos em até 30 dias após a colheita.

In order to keep the quality and increase the shelf-life during the postharvest of bananas 'Prata-Anã', the efficiency of cold storage (CS), the modified atmosphere (MA) by the use of low density polyethylene (LDPE) plastics bags, vacuum and use of sachet adsorption of ethylene was evaluated. The treatments were: T1: control (no packaging, system of ethylene adsorption or vacuum), T2: LDPE; T3: LDPE + system of ethylene adsorption; T4: LDPE + vacuum and T5: LDPE + system of ethylene adsorption + vacuum. Analysis were performed every 5 days after harvest, up to 35 days. It was verified that the fruit under LDPE bags showed the smallest areas with skin lesions, the lowest ethylene concentration, the lowest increments of titratable acidity (TA) and normal behavior/maintenance of pH levels. This possibly resulted in the highest contents of total and reduced sugars at the end of the experiment. Thus, it was concluded that the combined use of LDPE bags with the ethylene adsorbents sachets resulted in delaying in the process of bananas 'Prata-Anã' ripening, resulting, commercially, in the extension of shelf-life of banana for at least 30 days after harvest.

OBJECTIVE: To report short and midtem follow-up results of balloon aortic valvuloplasty to treat congenital aortic stenosis. METHODS: Seventy-five patients (median age: 8 years) underwent the procedure through the retrograde femoral or carotid route. RESULTS: The procedure was completed in 74 patients (98.6%). The peak-to-peak systolic gradient dropped from 79.6±27.7 to 22.3±17.8 mmHg (P<0.001), the left ventricular systolic pressure dropped from 164±39.1 to 110±24.8 mmHg (P<0.001), and the left ventricular end diastolic pressure dropped from 13.3±5.5 to 8.5±8.3 mmHg (P< 0.01). Four patients (5.3%) died due to the procedure. Aortic regurgitation (AoR) appeared or worsened in 27/71 (38%) patients, and no immediate surgical intervention was required. A mean follow-up of 50±38 months was obtained in 37 patients. Restenosis and significant AoR were observed in 16.6% of the patients. The estimates for being restenosis-free and for having significant AoR in 90 months were 60% and 50%, respectively. CONCLUSION: Aortic valvuloplasty was considered the initial palliative method of choice in managing congenital aortic stenosis, with satisfactory short- and midterm results.