Plants grown in elevated CO environments may exhibit photosynthetic acclimation or down regulation, which is characterised by 2 reduced rates of photosynthesis. In most cases of CO -induced photosynthetic acclimation, the reduced rates of photosynthesis were still 2 higher than those detected in plants growing at ambient CO concentrations. In this work we present a study on the behaviour of seedlings 2 of Hymenaea courbaril, a late secondary/climax species that is one of the most important trees in mature tropical forests of the Americas. After germination, the seedling of H. courbaril increases its rate of growth due to the mobilisation of massive amounts of a storage cell wall polysaccharide (xyloglucan) from its cotyledons. In our experiments, germinated seeds were incubated in open top chambers with increased concentration of atmospheric CO (720 ppm) (control at 360 ppm). To test the effects of the presence of the storage compound 2 on the responses of growing seedlings, cotyledons were detached before the start of polysaccharide mobilisation and parameters such as dry mass, leaf area, CO assimilation rates and chlorophyll a fluorescence were measured during 98 days. A comparison between 360 2 and 720ppm growing seedlings showed a significant increase in leaf area only in metaphylls of seedlings growing under higher CO . However, a marked and persistent increase (2 fold) in photosynthesis (CO assimilation) was observed in all cases (with or without 2 cotyledons). Changes in the levels of sucrose have been suggested to act as a signalling mechanism that switches on/off the storage or development mode in plant tissues. Thus, the explanation for our general observation that the differential response in terms of growth of seedlings ceases to exist when storage mobilisation is functioning, might be related to the fact that higher levels of sucrose are produced as a result of carbon storage compounds degradation. By the results obtained, it appears that plants grown under enriched CO did not 2 acclimate and therefore under the climatic conditions forecasted on the basis of the present carbon dioxide emissions, Hymenaea courbaril should establish faster in its natural environment and might also serve as an efficient mechanism of carbon sequestration within the forest. ResumoPlântulas de jatobá crescidas em ambiente com concentrações elevadas de CO podem exibir aclimatação fotossintética ou retro-2 inibição, a qual é caracterizada pela redução das taxas fotossintéticas. Em muitos casos de aclimatação induzida por alto CO , taxas 2 reduzidas de fotossíntese são observadas, mas ainda são mais altas que aquelas detectadas em plantas crescendo em concentrações atuais de CO atmosférico (360ppm). No presente trabalho, realizamos um estudo do comportamento de plântulas de Hymenaea courbaril, 2 uma espécie secundária tardia/clímax de grande importância em florestas tropicais maduras nas Américas. Em nossos experimentos, sementes recém germinadas foram cultivadas em câmaras de topo aberto com concentrações alteradas ...

O objetivo deste estudo foi avaliar a qualidade do carvão vegetal, utilizado para cocção de alimentos comercializado na cidade de Cuiabá, Mato Grosso. A seleção das marcas foi aleatória, finalizando ao verificar a repetição em diferentes estabelecimentos. Todos os produtos foram obtidos em embalagens de 3 kg, quantidade suficiente para as análises subsequentes. Foram avaliadas sete marcas de carvão vegetal, das quais foram determinadas as propriedades físicas: classificação granulométrica, densidade a granel, densidade relativa aparente, umidade; e análise imediata e poder calorífico superior e útil. Cerca de 70% das peças de carvão das marcas analisadas ficaram entre as granulometrias de 50 e 31,5 mm, a densidade aparente ficou acima de 380 kg.cm-3. A umidade variou de 4 a 10% e o carbono fixo de 57 a 85%. O poder calorífico superior apresentou correlação com o carbono fixo, variando de 6104 a 7527 kcal.kg-1 , e o poder calorífico útil variou de 5784 a 7098 kcal.kg-1 , em razão das diferentes umidades verificadas. O carvão vegetal analisado apresentou indicativos regulares para uso na cocção de alimentos.

RESUMO Não há um consenso entre as indústrias produtoras de carvão sobre qual tipo de madeira é mais adequada, ou seja, se é desejável maior proporção de cerne ou de alburno. Portanto, o objetivo deste trabalho foi avaliar as propriedades da madeira de cerne e alburno de dois clones (I e II) de Eucalyptus camaldulensis, destinados à produção de carvão vegetal. A densidade básica, caracterização anatômica das fibras, composição química, teor de cinzas e poder calorífico da madeira foram avaliados. Para os dois clones avaliados, as porcentagens de cerne diminuíram no sentido base-topo da árvore enquanto as porcentagens de alburno aumentam, sendo que o clone I tinha maiores porcentagens de cerne. A madeira de alburno apresentou maiores valores médios para densidade básica, fração parede, largura e espessura da parede das fibras. Já a região do cerne destacou-se com maiores valores médios de diâmetro do lume das fibras e teores de lignina e extrativos. Para cinzas e poder calorífico, os valores foram semelhantes para os tratamentos, 0,14% e 4649,0 kcal/kg, respectivamente. Conclui-se que o clone II é o indicado para a produção de carvão. Palavras-chave: carbonização; qualidade da madeira; densidade.

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ABSTRACT:Xylanases are useful in several industrial segments, including pulp and paper bleaching, animal feed, and bread-making processes. However, the industrial use of these enzymes is closely related to its production cost and its catalytic properties. The process of solid state fermentation enables the use of agro-industrial residues as substrates for microbial cultivation and enzymes production, reducing costs. In the present study, different cultivation parameters were evaluated for the xylanase production by the thermophilic fungus Thermoascus aurantiacus, by solid state fermentation, using agro-industrial residues as substrates. High production of xylanase (1701.9 U g -1 of dry substrate) was obtained using wheat bran containing 65% of initial moisture, at 120 h of cultivation, and 45°C. The xylanase showed optimal activity at pH 5.0 and 75°C; its stability was maintained at pH 3.0-11.0. The enzyme retained its catalytic potential after 1 h, at 75°C. The enzymatic extract produced under optimized conditions showed reduced activities of endoglucanase and FPase. Our results, including the xylanase production by T. aurantiacus in low-cost cultivation medium, high structural stability of the enzyme, and reduced cellulolytic activity, encourage the application of this enzymatic extract in pulp and paper bleaching processes.

Background: To evaluate the potential factors associated with the nutritional composition of human milk of puerperal women. Methods: cross-sectional study, conducted between March 2016 and August 2017, with 107 women, selected in a Tertiary Health Care Tertiary Health Facility of the Unified Health System (SUS) in the Municipality of Rio de Janeiro. Data were collected two months after delivery. The dependent variable of the study was the nutritional composition of human milk. We divided the independent variables into hierarchical levels: distal (age, schooling, parity and pregestational nutritional status), intermediate (number of prenatal visits and gestational weight gain) and proximal (alcohol consumption, smoking, diabetes mellitus and hypertension). For data analysis, we applied the multiple linear regression, centered on the hierarchical model. Only the variables associated with the nutritional composition of breast milk remained in the final model at a 5% level of significance. Results: The nutritional composition of human milk yielded by women with pregestational overweight, smokers and hypertensive had higher amounts of lipids and energy. Conversely, women with gestational weight gain below the recommended had lower amounts of these components. Conclusion: The evaluation of factors associated with the nutritional composition of human milk is extremely important to assist post-partum care practices. In this study, we observed that lipid and energy contents were associated to pregestational nutritional status, gestational weight gain, smoking and hypertension.

The proposed nanocomposite reveals leishmanial activity and the absence of cytotoxicity in macrophages. Further investigations will be conducted in vivo.

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