117 research outputs found

    Influence of adding kraft lignin in eucalyptus pellets properties

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    The pellets are becoming an important renewable source of energy for industrial and domestic use. The consumer market is increasingly demanding in terms of product quality and this may be improved through the use of various additives, such as kraft lignin. The objective of this study was to evaluate the quality of eucalyptus pellets produced with the addition of different percentages of kraft lignin. The raw material used for production of pellets was wood with bark of an Eucalyptus grandis x E. urophylla clone, with approximately five years of age, obtained from commercial planting, and 10% of waste of eucalyptus harvest (tops, leaves and branches). Excluding the control (0% lignin) was added 1, 2, 3, and 5% kraft lignin, relative to the dry mass of raw material. The pellets were produced in a laboratory pelletizer with a horizontal circular array. The following properties of the pellets were evaluated: moisture content, gross and net calorific value, unit density, bulk density, energy density, ash content, length and diameter, hardness, mechanical durability and fines content. The addition of kraft lignin contributed to improving the pellets physical and mechanical properties, as regards the density, mechanical durability, fines and hardness. The addition of lignin caused the elevation of the levels of ash and moisture content of the pellets. It is concluded that addition of lignin to pellet production is feasible, since lignin is used with lower contents of ash and moisture.Os pellets vêm se tornando uma importante fonte renovável de energia para utilização industrial e doméstica. O mercado consumidor está cada vez mais exigente quanto à qualidade do produto e essa pode ser melhorada por meio da utilização de diferentes aditivos, como a lignina kraft. Assim, o objetivo desse trabalho foi avaliar a qualidade dos pellets de eucalipto produzidos com adição de diferentes percentagens de lignina kraft. A matéria-prima utilizada para produção de pellets foi madeira com casca de um clone de Eucalyptus grandis x Eucalyptus urophylla com aproximadamente cinco anos de idade, proveniente de plantio comercial, além de 10% de resíduos da colheita do eucalipto (ponteira, folhas e galhos). Excluindo-se a testemunha (0% de lignina), adicionou-se 1, 2, 3, e 5% de lignina kraft, em relação à massa seca da matéria-prima. Os pellets foram produzidos em uma peletizadora laboratorial com matriz circular horizontal. Foram avaliadas as seguintes propriedades dos pellets: teor de umidade, poder calorífico superior e útil, densidade a granel e aparente, densidade energética, teor de cinzas, comprimento e diâmetro, dureza, durabilidade mecânica e teor de finos. A adição de lignina kraft em pellets de eucalipto contribuiu para a melhoria das propriedades físicas e mecânicas, no que se diz respeito à densidade, durabilidade mecânica, geração de finos e dureza. A adição de lignina ocasionou a elevação dos teores de cinzas e da umidade dos pellets. Conclui-se que a adição de lignina para produção de pellets é viável, desde que sejam utilizadas ligninas com menores teores de cinzas e umidade

    Perfil de qualidade de vida e felicidade dos moradores de um assentamento rural na Amazônia Brasileira

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    Introduction: quality of life (QOL) is the individual's perception of their position in life, in the cultural context and in the value system. Objective: to evaluate the QOL and the happiness level of the community of the Nova Amazônia Settlement Project (PANA). Methodology: observational, transversal, prospective, descriptive, qualitative and quantitative study, involving 184 residents of PANA. Data collection was carried out between November 2019 and September 2020, using the WHOQOL-100 questionnaire and a happiness scale developed by Lyubomirsky and Lepper. Results: there was an association between being a man and having a better score in the Physical domain (p = 0.014), being a woman and a better score in the Spirituality / Beliefs domain (p = 0.030), having a higher income and a better score in the Environment domain (p = 0.0003), having a higher level of education and a better global assessment of QOL (p = 0.008) and better scores in the domains Independence (p = 0.023) and Environment (p = 0.015), being 18 to 39 years old and having a better score in Independence domain (p = 0.007) and between living in the settlement for less time and having more independence (p = 0.023). No association was found between sociodemographic data and the level of happiness. Conclusion: Despite all the economic and social difficulties experienced by the studied population, both the QOL and happiness scores are at a median level. The Physical and Environmental domains were the most fragile, with the lowest scores and the main problems pointed out by the participants were the occurrence of musculoskeletal pain, the home environment, absence of leisure / recreation and the inefficiency of public transport Keywords: Quality of life;  Happiness; Rural population.Introdução: qualidade de vida (QV) é a percepção do indivíduo de sua posição na vida, no contexto cultural e no sistema de valores. Objetivo: avaliar a QV e o nível de felicidade da comunidade do Projeto de Assentamento Nova Amazônia (PANA). Metodologia: estudo, observacional, transversal, prospectivo, descritivo, quantitativo e qualitativo, envolvendo 184 moradores do PANA. A coleta de dados foi realizada entre novembro de 2019 e setembro de 2020, por meio da aplicação do questionário WHOQOL-100 e de uma escala de felicidade desenvolvida por Lyubomirsky e Lepper. Resultados: evidenciou-se associação entre ser homem e ter melhor escore no domínio Físico (p= 0,014), ser mulher e melhor escore no domínio Espiritualidade/ Crenças (p= 0,030), ter maior renda e melhor escore no domínio Ambiente (p= 0,0003), ter maior nível de escolaridade e melhor avaliação global de QV (p= 0,008) e melhores escores nos domínios Independência (p= 0,023) e Ambiente (p= 0,015), ter de 18 a 39 anos e melhor escore no domínio Independência (p= 0,007) e entre morar no assentamento há menos tempo e ter mais independência (p=0,023). Não foi evidenciada associação entre os dados sociodemográficos e o nível de felicidade.  Conclusão: Apesar de toda a dificuldade econômica e social vivenciada pela população estudada, tanto os escores de QV quanto de felicidade encontram-se em um patamar mediano. Os domínios Físico e Ambiental foram os mais fragilizados, apresentando os menores escores e os principais problemas apontados pelos participantes foram a ocorrência de dores osteomusculares, o ambiente do lar, ausência de lazer/recreação e a ineficiência do transporte público Palavras-chave: Qualidade de vida; Felicidade; População rural

    Leaf and Root Extracts from Campomanesia adamantium (Myrtaceae) Promote Apoptotic Death of Leukemic Cells via Activation of Intracellular Calcium and Caspase-3

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    Phytochemical studies are seeking new alternatives to prevent or treat cancer, including different types of leukemias. Campomanesia adamantium, commonly known as guavira or guabiroba, exhibits pharmacological properties including antioxidant, antimicrobial, and antiproliferative activities. Considering the anticancer potential of this plant species, the aim of this study was to evaluate the antileukemic activity and the chemical composition of aqueous extracts from the leaves (AECL) and roots (AECR) of C. adamantium and their possible mechanisms of action. The extracts were analyzed by LC-DAD-MS, and their constituents were identified based on the UV, MS, and MS/MS data. The AECL and AECR showed different chemical compositions, which were identified as main compounds glycosylated flavonols from AECL and ellagic acid and their derivatives from AECR. The cytotoxicity promoted by these extracts were evaluated using human peripheral blood mononuclear cells and Jurkat leukemic cell line. The cell death profile was evaluated using annexin-V-FITC and propidium iodide labeling. Changes in the mitochondrial membrane potential, the activity of caspases, and intracellular calcium levels were assessed. The cell cycle profile was evaluated using propidium iodide. Both extracts caused concentration-dependent cytotoxicity only in Jurkat cells via late apoptosis. This activity was associated with loss of the mitochondrial membrane potential, activation of caspases-9 and -3, changes in intracellular calcium levels, and cell cycle arrest in S-phase. Therefore, the antileukemic activity of the AECL and AECR is mediated by mitochondrial dysfunction and intracellular messengers, which activate the intrinsic apoptotic pathway. Hence, aqueous extracts of the leaves and roots of C. adamantium show therapeutic potential for use in the prevention and treatment of diseases associated the proliferation of tumor cell.Fundação de Apoio ao Desenvolvimento do Ensino, Ciência e Tecnologia do Mato Grosso do Sul (FUNDECT)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Instituto Nacional de Pesquisa do Pantanal - INPPFundação de Amparo e Desenvolvimento da Pesquisa FadespFed Univ Grande Dourados, Res Grp Biotechnol & Bioprospecting Appl Metab, Dourados, BrazilUniv Fed São Paulo, Dept Biochem, São Paulo, BrazilUniv Braz Cubas, Fac Pharm, Mogi Das Cruzes, BrazilUniv Mogi das Cruzes, Interdisciplinary Ctr Biochem Invest, Mogi Das Cruzes, BrazilUniv Fed São Paulo, Dept Pharmaceut Sci, São Paulo, BrazilUniv Fed Mato Grosso do Sul, Lab Nat Prod & Mass Spectrometry, Campo Grande, MS, BrazilUniv Fed São Paulo, Dept Biochem, São Paulo, BrazilUniv Fed São Paulo, Dept Pharmaceut Sci, São Paulo, BrazilWeb of Scienc

    Methodological approaches for studying the microbial ecology of drinking water distribution systems

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    The study of the microbial ecology of drinking water distribution systems (DWDS) has traditionally been based on culturing organisms from bulk water samples. The development and application of molecular methods has supplied new tools for examining the microbial diversity and activity of environmental samples, yielding new insights into the microbial community and its diversity within these engineered ecosystems. In this review, the currently available methods and emerging approaches for characterising microbial communities, including both planktonic and biofilm ways of life, are critically evaluated. The study of biofilms is considered particularly important as it plays a critical role in the processes and interactions occurring at the pipe wall and bulk water interface. The advantages, limitations and usefulness of methods that can be used to detect and assess microbial abundance, community composition and function are discussed in a DWDS context. This review will assist hydraulic engineers and microbial ecologists in choosing the most appropriate tools to assess drinking water microbiology and related aspects

    Germ band retraction as a landmark in glucose metabolism during Aedes aegypti embryogenesis

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    <p>Abstract</p> <p>Background</p> <p>The mosquito <it>A. aegypti </it>is vector of dengue and other viruses. New methods of vector control are needed and can be achieved by a better understanding of the life cycle of this insect. Embryogenesis is a part of <it>A. aegypty </it>life cycle that is poorly understood. In insects in general and in mosquitoes in particular energetic metabolism is well studied during oogenesis, when the oocyte exhibits fast growth, accumulating carbohydrates, lipids and proteins that will meet the regulatory and metabolic needs of the developing embryo. On the other hand, events related with energetic metabolism during <it>A. aegypti </it>embryogenesis are unknown.</p> <p>Results</p> <p>Glucose metabolism was investigated throughout <it>Aedes aegypti </it>(Diptera) embryonic development. Both cellular blastoderm formation (CBf, 5 h after egg laying - HAE) and germ band retraction (GBr, 24 HAE) may be considered landmarks regarding glucose 6-phosphate (G6P) destination. We observed high levels of glucose 6-phosphate dehydrogenase (G6PDH) activity at the very beginning of embryogenesis, which nevertheless decreased up to 5 HAE. This activity is correlated with the need for nucleotide precursors generated by the pentose phosphate pathway (PPP), of which G6PDH is the key enzyme. We suggest the synchronism of egg metabolism with carbohydrate distribution based on the decreasing levels of phosphoenolpyruvate carboxykinase (PEPCK) activity and on the elevation observed in protein content up to 24 HAE. Concomitantly, increasing levels of hexokinase (HK) and pyruvate kinase (PK) activity were observed, and PEPCK reached a peak around 48 HAE. Glycogen synthase kinase (GSK3) activity was also monitored and shown to be inversely correlated with glycogen distribution during embryogenesis.</p> <p>Conclusions</p> <p>The results herein support the hypothesis that glucose metabolic fate changes according to developmental embryonic stages. Germ band retraction is a moment that was characterized as a landmark in glucose metabolism during <it>Aedes aegypti </it>embryogenesis. Furthermore, the results also suggest a role for GSK3 in glycogen balance/distribution during morphological modifications.</p

    Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

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    The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe

    Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

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    Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

    Pervasive gaps in Amazonian ecological research

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    Improved risk stratification of patients with atrial fibrillation: an integrated GARFIELD-AF tool for the prediction of mortality, stroke and bleed in patients with and without anticoagulation.

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    OBJECTIVES: To provide an accurate, web-based tool for stratifying patients with atrial fibrillation to facilitate decisions on the potential benefits/risks of anticoagulation, based on mortality, stroke and bleeding risks. DESIGN: The new tool was developed, using stepwise regression, for all and then applied to lower risk patients. C-statistics were compared with CHA2DS2-VASc using 30-fold cross-validation to control for overfitting. External validation was undertaken in an independent dataset, Outcome Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF). PARTICIPANTS: Data from 39 898 patients enrolled in the prospective GARFIELD-AF registry provided the basis for deriving and validating an integrated risk tool to predict stroke risk, mortality and bleeding risk. RESULTS: The discriminatory value of the GARFIELD-AF risk model was superior to CHA2DS2-VASc for patients with or without anticoagulation. C-statistics (95% CI) for all-cause mortality, ischaemic stroke/systemic embolism and haemorrhagic stroke/major bleeding (treated patients) were: 0.77 (0.76 to 0.78), 0.69 (0.67 to 0.71) and 0.66 (0.62 to 0.69), respectively, for the GARFIELD-AF risk models, and 0.66 (0.64-0.67), 0.64 (0.61-0.66) and 0.64 (0.61-0.68), respectively, for CHA2DS2-VASc (or HAS-BLED for bleeding). In very low to low risk patients (CHA2DS2-VASc 0 or 1 (men) and 1 or 2 (women)), the CHA2DS2-VASc and HAS-BLED (for bleeding) scores offered weak discriminatory value for mortality, stroke/systemic embolism and major bleeding. C-statistics for the GARFIELD-AF risk tool were 0.69 (0.64 to 0.75), 0.65 (0.56 to 0.73) and 0.60 (0.47 to 0.73) for each end point, respectively, versus 0.50 (0.45 to 0.55), 0.59 (0.50 to 0.67) and 0.55 (0.53 to 0.56) for CHA2DS2-VASc (or HAS-BLED for bleeding). Upon validation in the ORBIT-AF population, C-statistics showed that the GARFIELD-AF risk tool was effective for predicting 1-year all-cause mortality using the full and simplified model for all-cause mortality: C-statistics 0.75 (0.73 to 0.77) and 0.75 (0.73 to 0.77), respectively, and for predicting for any stroke or systemic embolism over 1 year, C-statistics 0.68 (0.62 to 0.74). CONCLUSIONS: Performance of the GARFIELD-AF risk tool was superior to CHA2DS2-VASc in predicting stroke and mortality and superior to HAS-BLED for bleeding, overall and in lower risk patients. The GARFIELD-AF tool has the potential for incorporation in routine electronic systems, and for the first time, permits simultaneous evaluation of ischaemic stroke, mortality and bleeding risks. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier for GARFIELD-AF (NCT01090362) and for ORBIT-AF (NCT01165710)
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