ABSTRACT Introduction: The long-term consequences of COVID-19, especially pulmonary impairment, are frequent but not well understood. The knowledge about sequels or long COVID-19 are necessary, considering the high prevalence and need for specific public strategies. Method: The study was conducted to evaluate symptoms (standardized questionnaire), pulmonary function (spirometry), and exercise capacity (6-minute-walk-test) at 30 (D30), 90 (D90), and 180 (D180) days after hospital discharge of patients surviving to severe COVID-19. We excluded in this follow up patients with comorbidities before COVID infection. Results: 44 patients were included and 31 (26 men) completed the 6-month follow-up (age mean 53.6 ± 9.6 years). At D180, 28% presented still at least one symptom. The most common was dyspnea (17.2%), followed by cough (13.8%), and myalgia (10.3%). All spirometric parameters showed progressive improvement from D30 to D180. However, 16% maintained a restrictive pattern on spirometry test, 44% presented desaturation on the 6-minute walk-test, and 25% walked < 75% of the predicted value. Conclusion: 6-months after hospital discharge, reduced pulmonary function and reduced exercise capacity was founded frequently and more than a quarter remained symptomatic. The persistent symptoms and functional impairment suggest that sequels and development of Long COVID-19 are very common. The identification of these patients to provide the necessary health care is a challenging task, considering the large number of patients infected and surviving to COVID-19 disease.

Abstract Probiotics can be defined as viable or inviable microbial cell (vegetative/spore or intact/ruptured) that is potentially healthful to the host. Commonly linked to fermented milk, one of the most popular fermented beverage, due to the greater consumer acceptance of dairy products. However, technical aspects such as inappropriate storage conditions and transport facilities can influence the viability of the microorganisms in these products. Therefore, the aim of this study was to evaluate the microbiological and physicochemical quality of probiotic fermented milk sold in the city of Botucatu/SP during its shelf life, and to determine the effect of different storage temperatures (4 °C and 12 °C), comparing results with the standard limits. For this purpose, four brands of probiotic fermented milk (A, B, C, and D) were analyzed counting lactic acid bacteria and evaluating physicochemical parameters (pH, acidity, proteins, lipids, moisture, and ash). As a result, only brand D did not fit the parameters determined by the technical norms of the Brazilian legislation; the variation in storage temperature, did not show significant influence on the results of the tested parameters.

Abstract The physicochemical quality parameters of meat from finishing lambs supplemented with quebracho tannin extract (QTE) were evaluated. Lambs were assigned to four treatment groups: CON—animals fed basal diet (BD); QTE 1% (T1%)—BD + tannins at 1% dry matter intake (DMI); QTE 3% (T3%)—BD + tannins at 3% DMI; and QTE 6% (T6%)—BD + tannins at 6% DMI. Longissimus thoracis et lumborum samples were vacuum packaged and stored at 4 °C for 28 days. The samples were evaluated weekly for proximate composition, pH, color, myoglobin forms, cooking loss, shear force, lipid (thiobarbituric acid reactive substances—TBARS), and protein (carbonyl and thiol) oxidation. Chemical composition and pH did not vary among treatments. The meat from lambs fed with higher proportion of QTE (T6%) presented lower redness, chroma, and oxymyoglobin content, and higher yellowness, hue angle, cooking loss, shear force, TBARS, and carbonyl content than the meat from the other groups. Our findings indicate that higher dose of QTE may exert pro-oxidative effects in lamb meat, negatively affecting its quality.

Resumo O presente estudo teve como objetivo verificar a influência do estresse no uso de substâncias psicoativas em universitários. Participaram da pesquisa 166 discentes, sem restrição de gênero, de um Campus de Ciências da Saúde de uma Universidade do Nordeste do Brasil. Para avaliar o estresse foi utilizado o Inventário de Sintomas de Stress para Adultos de Lipp e para análise do uso de substâncias psicoativas foi utilizado o teste de triagem ASSIST. Para análise estatística foram utilizados os testes de Mann Whitney, Kruskal-Wallis e de correlação de Spearman (considerado significativo quando p<0,05). Houve diferença significativa entre o uso de psicoativos em pessoas com e sem estresse. Não houve diferença significativa entre os resultados de estresse e de uso de psicoativos entre os gêneros estudados e entre os cursos. Foram detectados com estresse 125 (75,3%) participantes, sendo a fase de resistência a mais frequente. A predominância das sintomatologias encontradas foi a psicológica. As substâncias psicoativas mais utilizadas pelos estudantes foram álcool, tabaco e maconha, com total de 74 (42,8%) pessoas com necessidade de encaminhamento para algum tipo de intervenção referente ao consumo destas substâncias. Houve correlação forte e significativa entre o número de pessoas com estresse e com necessidade de alguma intervenção devido o uso de psicoativos. O estudo evidencia a relação entre a presença de estresse e o uso de psicoativos em estudantes universitários.

Abstract The present stud to verify the influence of stress on psychoactive substance use. The specific objectives were: Verify the stress phases (alarm, resistance, near-exhaustion and exhaustion) and the predominance of symptoms (whether psychological or physical) in the different courses studied and describe the substance use profile. psychoactive in the sample studied. One hundred and sixty-six students, without gender restriction, participated in the research from a Health Sciences Campus of a University of Northeast Brazil. To assess stress, the Lipp Adult Stress Symptom Inventory was used and the analysis of psychoactive substance use was the ASSIST screening test. For statistical analysis we used the Mann Whitney, Kruskal-Wallis and Spearman correlation test (considered significant when p <0.05). There was a significant difference between psychoactive use in people with and without Stress. There was no significant difference between the results of stress and psychoactive use among the studied genders and between the courses. 125 (75.3%) participants were detected with stress, being the most frequent phase of resistance. The predominance of the symptoms found was psychological. The psychoactive substances most used by students were alcohol, tobacco and cannabis, with a total of 74 (42.8%) people in need of referral for some type of intervention regarding the consumption of these substances. There was a strong and significant correlation between the number of people with stress and needing some intervention due to psychoactive use. The study shows the relationship between the presence of stress and psychoactive use.

Resumo A conversão fotovoltaica de energia é uma área de pesquisa muito ativa devido à necessidade de ampliar a participação das fontes de energia renováveis na matriz energética global. Os esforços de pesquisa vão desde a modelagem de dispositivos fotovoltaicos a partir de princípios físicos fundamentais ou fenomenologias, passando pelo desenvolvimento e caracterização de novos materiais e dispositivos aplicáveis na conversão fotovoltaica e indo até os estudos de impacto ambiental e aspectos econômicos. No presente trabalho, utilizando-se do modelo de sistema de dois níveis acoplado a um campo de fótons, apresentam-se os princípios físicos da conversão fotovoltaica de energia. Com isso, além de servir de rápido guia para os pesquisadores e estudantes no campo da conversão fotovoltaica, o problema spin-bóson é utilizado de forma pedagógica para servir como um exercício contextualizado de mecânica quântica e física dos semicondutores.

Abstract Photovoltaic energy conversion is an extraordinarily active research field, mainly due to the need for increasing the participation of renewable energy sources in the world energy matrix. Research efforts range from the photovoltaic devices modelling from first principles or using phenomenology and the development and characterization of novel photovoltaic materials and devices to environmental and economical aspects of photovoltaic energy. The present work presents the physical aspects of photovoltaic energy conversion, using in a pedagogical way a two system level coupled to a photon field as a toy model to discuss the main ideas, serving as a quick guide for researchers and students in the field.

Resumo A geometria fractal fascina pela capacidade de descrever formas geométricas complexas e que usualmente estão presentes no mundo real . A dimensão fractal ou de Hausdorff d é utilizada para descrever leis de invariância de escala, em que as funções autossimilares seguem uma lei da forma f ( s x ) = s d f ( x ), sendo s o fator de escala. Intimamente relacionado ao problema da invariância de escala está o problema da determinação dos pontos fixos de um sistema, que matematicamente correspondem aos pontos que mapeiam o domínio de uma função para ele mesmo. Em sistemas dinâmicos correspondem ao valor para o qual a resposta do sistema usualmente converge e permanece estável. Na presente contribuição são apresentados os conceitos gerais associados à invariância de escala e ponto fixo, para prontamente empregá-los no problema de associação de impedâncias complexas em série e em topologia de escada. São discutidos em detalhes o problema da função de transferência de linhas de transmissão e o estudo de alguns gráficos de fluxo (flow graphs) de convergência das equações de recursividade.

Abstract Fractal geometry is fascinating due to its ability to describe the complex geometries naturally occurring in real world. The fractal or Hausdorff dimension d is used to describe the laws of scale invariance, which are exemplified by functions satisfying a mathematical law of the form f ( s x ) = s d f ( x ), being s the scale factor. Closely related is the problem of determining the fixed point of physical systems. Mathematically, the fixed point corresponds to a point in the domain of a function which is mapped to itself. In dynamical systems, it typically corresponds to the value to which the response of the system converge and stabilize. The present contribution aims to present the general concepts of scale invariance and fixed or critical points, employing such aspects to the problem of complex impedance association, both in series and in ladder configuration. The complex impedance, and transfer function of transmission lines and flow graphs related to the convergence the iterative equations to a fixed points are discussed in more details.

Resumen El objetivo de este estudio fue caracterizar la variabilidad espacial del pH para suelos de dos fincas en el estado de Paraná, Brasil, con base en dos métodos diferentes de muestreo utilizados en agricultura de precisión, mediante análisis geoestaddísticos. El primero método de muestreo del pH consistió en la colecta de muestras de suelo por ele método tradicional (1punto/ha). El segundo método de determinación del pH fue el sensor de suelo dinâmico (200 puntos / ha). El modelo esférico fue más adecuado para la mayoría de los semivariogramas, independientemente del método de muestreo. La mejor distribución espacial fue obtenida por la cualidad del muestreado del sensor de suelo dinâmico. El número de muestras del pH colectadas y el método de muestreo influyeron en la representación visual de la variabilidad del pH.

Abstract This study aimed to characterize the spatial variability of pH in soils of two farms in the state of Paraná, Brazil, based on two different sampling methods used in precision agriculture, by means of geostatistical analyzes. The first method of sampling the pH grid consisted in the collection of soil samples by the traditional method (1 point / ha). The second method of pH determination was by on-the-go soil sensor (200 points / ha). The spherical model was better suited to most semivariograms, regardless of the sampling method. After adjusting the semivariograms for soil pH determination methods, thematic maps were made using normal kriging. The best spatial distribution of pH was obtained where the attribute was sampled by the on-the-go sensor. The number of pH samples collected and the sampling method influenced the visual representation of pH variability.

RESUMO. O objetivo do experimento foi avaliar a composição nutricional, a recuperação de matéria seca (MS) e a estabilidade aeróbia de silagens de cereais de inverno submetidas a diferentes tempos de estocagem. Os materiais utilizados foram o trigo (Triticum aestivum cv. BRS Gralha Azul), cevada (Hordeum vulgare cv. BRS Brau), aveia branca (Avena sativa cv. URS Guará), aveia preta (Avena strigosa cv. Embrapa 139) e triticale (X Triticosecale cv. IPR 11), em três tempos de estocagem: 60, 120 e 180 dias. O delineamento experimental foi inteiramente casualizado em arranjo fatorial 5x3. Na avaliação nutricional, a silagem de cevada apresentou baixos teores de fibra em detergente ácido (FDA; 331; 355 e 378 g kg MS-1, para 60, 120 e 180 dias, respectivamente) e altos de nutrientes digestíveis totais (NDT; 558; 544 e 531 g kg MS-1 para 60, 120 e 180 dias, respectivamente), além de alta recuperação de MS e estabilidade aeróbia. O trigo e o triticale apresentaram decréscimo na recuperação de MS com o aumento dos dias de estocagem, embora tenham apresentado alta estabilidade aeróbia. O tempo de estocagem influenciou de maneira distinta as forrageiras, no entanto, tempos de estocagem acima de 60 dias não proporcionaram benefícios para as variáveis avaliadas.

ABSTRACT. The objective of the experiment was to evaluate the nutritional composition, dry matter (DM) recovery and aerobic stability of winter cereal silages under different storage periods. The materials used were wheat (Triticum aestivum cv. BRS Gralha Azul), barley (Hordeum vulgare cv. BRS Brau), white oat (Avena sativa cv. URS Guará), black oat (Avena strigosa cv. Embrapa 139) and triticale (X Triticosecale IPR 11), in three storage periods: 60, 120 and 180 days. The experiment was conducted in a 5x3 factorial, completely randomized design, consisting of five forage species and three storage periods, with five replicates. In nutritional assessment, barley silage presented low values of acid detergent fiber (ADF; 331.2, 355.2 and 378.5 g kg DM-1 for 60, 120, 180 days, respectively), high total digestible nutrients (TDN; 558.2, 544.7 and 531.6 g kg DM-1 for 60, 120, 180 days, respectively), high DM recovery and aerobic stability. Wheat and triticale showed a decrease in DM recovery with the increase in storage length, although showed high aerobic stability. The storage period had a different effect on forages; however, storage period above 60 days provided no benefits for the variables evaluated.

RESUMO Objetivou-se, com o presente estudo, aplicar técnicas de agricultura de precisão no cultivo do café utilizando análise de correlação na definição de zonas de manejo. O trabalho foi desenvolvido em uma área de 22 ha de lavoura de cafeeiro (Coffea arabica L.) da cultivar Topázio MG 1190. Demarcou-se na área em estudo e com a utilização de GPS topográfico, uma malha amostral regular totalizando 64 pontos amostrais georreferenciados (em média 2,9 pontos por ha). Utilizou-se o método de análise descritiva dos dados seguido da análise de correlação de Pearson a 0,05 de significância entre os atributos de solo, características agronômicas da planta e altitude. Foi possível verificar a correlação dos atributos do solo, das características agronômicas das plantas e da altitude com a produtividade. Através da análise de correlação observou-se que a altitude foi a variável que mais se correlacionou com a produtividade sendo, assim, selecionada como variável mais propícia para geração de zonas de manejo e de mapas temáticos capazes de auxiliar os cafeicultores. Foram gerados três mapas que caracterizam a área em duas, três e quatro zonas de manejo. Verificou-se que houve influência direta na média da produtividade.

ABSTRACT This study aimed to apply precision agriculture techniques in coffee production, using correlation analysis in the definition of management zones. This work was carried out in a 22-ha area of coffee (Coffea arabica L.), cv. ‘Topázio MG 1190’, which was sampled on a regular grid, using a topographic GPS, totaling 64 georeferenced samples (on average, 2.9 points per ha). Descriptive analysis was used in the data, followed by Pearson’s correlation analysis at 0.05 significance between soil chemical attributes, agronomic characteristics of the plants and altitude. It was possible to verify the correlation of soil chemical attributes, agronomic characteristics of the plants and altitude with coffee yield. Altitude was the variable most correlated with coffee yield through correlation analysis. Therefore, it was chosen as the best variable to define management zones and thematic maps capable to support coffee farmers. Three maps were generated to characterize the area in two, three and four management zones. There was a direct influence on mean yield.

RESUMO Objetivou-se neste estudo avaliar a atividade antifúngica do extrato metanólico e frações das folhas de Randia nitida (Kunth) DC. sobre Colletotrichum truncatum (Schw.) Andrus & Moore, Rhizoctonia solani Kühn e Sclerotinia sclerotiorum (Lib.) de Bary e realizar análise química e atividade antioxidante. O extrato metanólico bruto (EBM) e frações (hexânica= FHX, diclorometano= FDM e acetato de etila= FAE) foram submetidas a análise fitoquímica clássica e determinado os fenóis totais, flavonoides e atividade antioxidante. As amostras foram incorporadas, individualmente, ao meio de cultura BDA (batata-dextrose-ágar) nas concentrações de: 10, 20, 40, 80 e 160 µg mL-1 de extrato ou fração. O crescimento micelial foi avaliado quando a testemunha alcançou a borda da placa. Os resultados fitoquímicos indicaram que os flavonoides, esteroides e triterpenos são os constituintes químicos majoritários no EBM e nas frações. O teor de fenóis totais, flavonoides e a atividade antioxidante foi maior para a fração FAE e extrato EBM, seguido da fração FDM e da FHX, contudo a fração hexânica apresentou maior conteúdo de esteroides e triterpenos em relação as demais frações. Para os três fungos, as frações eficientes foram as frações FAE, FDM e FHX, respectivamente, todas na maior concentração estudada (160 µg mL-1). A maior porcentagem de inibição foi observada frente ao patógeno S. sclerotiorum, chegando a 93,75%. Conclui-se que todas as frações apresentam atividade antifúngica sobre os fitopatógenos e a fração FHX foi a mais ativa frente a Sclerotinia sclerotiorum, provavelmente pela presença de esteroides e triterpenos.

ABSTRACT This study aimed to evaluate the antifungal activity of methanol extract and fractions of leaves of Randia nitida (Kunth) DC on Colletotrichum truncatum (Schw.) Andrus & Moore, Rhizoctonia solani Kühn and Sclerotinia sclerotiorum (Lib.) De Bary and perform chemical and antioxidant activity tests. Crude methanol extract (EBM) and fractions (hexane = FHX, dichloromethane = FDM and ethyl acetate = FAE) underwent classical phytochemical analysis and determination of total phenols, flavonoids and antioxidant activity. Samples were individually incorporated into PDA culture mediums (potato-dextrose-agar) at concentrations of 10, 20, 40, 80 and 160 µg mL-1 of extract or fraction. Mycelial growth was evaluated when control reached the edge of the plate. Phytochemical results indicated that flavonoids, steroids and triterpenoids are the major chemical constituents in both EBM and fractions. Total phenols, flavonoids and antioxidant activity were higher for FAE and EBM, followed by FDM and FHX; however, the latter showed higher content of steroids and triterpenoids compared to the other fractions. For C. truncatum, R. solani and S. sclerotiorum, the most efficient fractions were respectively FAE, FDM and FHX, all of them in the highest concentration (160 µg mL-1). The highest inhibition rate was observed against S. sclerotiorum, reaching 93.75%. We concluded that all fractions have antifungal activity on the plant pathogens, being FHX the most active against S. sclerotiorum, which might have been due to the presence of steroids and triterpenes.