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Influence of variables related to soil weathering on the geomechanical performance of tropical soils

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2423-2440页

作者： Rodrigo Cesar Pierozan Gregorio Luís silva Araújo Ennio Marques palmeira Celso Romanel Department of Civil Engineering Federal Institute of EducationScienceand Technology of RondoniaPorto VelhoROBrazil Department of Civil and Environmental Engineering University of BrasiliaBrasiliaDFBrazil Department of Civil and Environmental Engineering Pontifical Catholic University of Rio de JaneiroRio de JaneiroRJBrazil

This paper presents an experimental and analytical investigation of the influence of variables related to soil weathering on the geomechanical performance of sand-silt mixtures containing lateritic soils,*** weathered tropical soils with the influence of interparticle *** sand-silt mixtures containing different relative proportions between uniform sand and lateritic soil were produced,and geomechanical soil characterization tests were *** on the results,a transition from a primarily coarse-to a fine-grained prevailing soil structure was found to cause considerable impact on the geomechanical performance of these soils,as evidenced by design variables related to soil mineralogy and size distribution ***,fines contents of both individual soil particles and soil aggregations were found to correlate with experimental results,while the relative proportion between sesquioxides(aluminum,and iron oxides),and silica,***-silica ratios(SSR^(-1)),facilitated estimates concerning changes in geomechanical ***,the application of the sandsilt mixtures containing lateritic soil on soil walls reinforced with polymeric strips was also evaluated,further emphasizing the potential advantages of adopting variables related to soil weathering on design guidelines concerning tropical soils.

关键词： Sesquioxides-silica ratio Tropical soils Sand-silt mixtures Lateritic soil Reinforced soil walls

An empiric equation for the latent heat of vaporization of moisture in bananas during its isothermal drying

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Agricultural Sciences 2012年第2期3卷 214-220页

作者： Wilton Pereira da silva Cleide Maria Diniz Pereira da silva e silva Fernando José de Almeida Gama Josivanda palmeira Gomes Federal University of Campina Grande Campina Grande Brazil

In order to determine the energy needed to artificially dry a product, the latent heat of vaporization of moisture in the product, hfg, must be known. Generally, the expressions for hfg reported in the literature are of the form hfg = h(T)f(M), where h(T) is the latent heat of vaporization of free water, and f(M) is a function of the equilibrium moisture content, M. But expressions of this type contain a simplification because, in this case, the ratio hfg/h would only depend to the moisture content. In this article a more general expression for the latent heat of vaporization, namely hfg = g(M,T), is used to determine hfg for banana. To this end, a computer program was developed which fits automatically about 500 functions, with one or two independent variables, imbedded in its library to experimental data. The program uses nonlinear regression, and classifies the best functions according to the least reduced chi-square. A set of executed statistical tests shows that the generalized expression used in this work given by hfg = g(M,T) produces better results of hfg for bananas than other equations found in the literature.

关键词： Energy Agricultural Products Dried Banana Heat and Mass Transfer

Diffusion models for the description of seedless grape drying using analytical and numerical solutions

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Agricultural Sciences 2012年第4期3卷 545-556页

作者： Wilton Pereira da silva Cleide Maria Diniz Pereira da silva e silva Jürgen Wolfgang Precker Josivanda palmeira Gomes Pedro Luiz Nascimento Laerson Duarte da silva Federal University of Campina Grande Campina Grande PB Brazil

This article compares diffusion models used to describe seedless grape drying at low temperature. The models were analyzed, assuming the following characteristics of the drying process: boundary conditions of the first and the third kind;constant and variable volume, V;constant and variable effective mass diffusivity, D;constant convective mass transfer coefficient, h. Solutions of the diffusion equation (analytical and numerical) were used to determine D and h for experimental data of seedless grape drying. Comparison of simulations of drying kinetics indicates that the best model should consider: 1) shrinkage;2) convective boundary condition;3) variable effective mass diffusivity. For the analyzed experimental dataset, the best function to represent the effective mass diffusivity is a hyperbolic cosine. In this case, the statistical indicators of the simulation can be considered excellent (the determination coefficient is R2 = 0.9999 and the chi-square is χ2 = 3.241 × 10–4).

关键词： Optimization Convective Boundary Condition Diffusion Model Finite Volume Method

Chemical Composition of the Cashew Apple Bagasse and Potential Use for Ethanol Production

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Advances in Chemical Engineering and Science 2012年第4期2卷 519-523页

作者： Flávia Cristina dos Santos Lima Flávio Luiz Honorato da silva Josivanda palmeira Gomes José Mariano da silva Neto Department of Chemical Engineering Center of Sciences and TechnologyFederal University of Campina GrandeCampina GrandeBrazil Department of Chemical Engineering Center of TechnologyFederal University of ParaibaJoao PessoaBrazil Department of Agricultural Engineering Center of Science and TechnologyFederal University of Campina GrandeCampina GrandeBrazil

On the world scene, the energy requirements are mainly based on fossil fuels, however, these compounds reserves are finite and their exploitation has caused serious environmental problems. As a consequence, the demand for alternative renewable sources has been intensified in substitution the rising demand for energy and raw materials. The biomass is emerging as one of the few sources that have potential to meet these challenges of sustainability, as is currently the largest energy resource in the world, and only carbon-rich material available on the planet, apart from fossils. Form, the cashew crop has great potential for technological development of alternative sources of energy, from its industrial waste processing cashew adding value to the product. In this sense, this paper aims to study the characterization of the cashew apple bagasse and to verify (by acid prehydrolysis) the potential of this material for ethanol production. Initially it was carried out physicochemical characterization of cashew bagasse used (pH, moisture content, soluble solids, sugars, cellulose, hemicellulose and lignin). Following it was carried prehydrolysis at 105℃ for 1h to obtain fermentable sugars. Analyses of the samples were carried out on HPLC the results showed the saccharification of biomass with glucose (1537.49 mg/L), xylose (3823.22 mg/L) and arabinose (7131.11 mg/L) as well as the capacity of the biomass for ethanol production.

关键词： Pre-Hydrolyze Ethanol Cashew Apple Bagasse

Electrochemical Evaluation of Aminoguanidine Hydrazone Derivative with Potential Anticancer Activity:Studies of Glassy Carbon/CNT and Gold Electrodes Both Modified with PAMAM

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Journal of Biomaterials and Nanobiotechnology 2020年第1期11卷 33-48页

作者： Marilya palmeira Galdino da silva Ygor Mendes de Oliveira Anna Caroline Lima Candido Joao Xavier de Araujo-Junior Erica Erlanny da silva Rodrigues Kadja Luana Chagas Monteiro Thiago Mendonca de Aquino Fabiane Caxico de Abreu Institute of Chemistry and Biotechnology Federal University of AlagoasMaceioALBrazil Institute of Pharmaceutical Sciences Federal University of AlagoasMaceioALBrazil

Aminoguanidine hydrazones (AGHs) are a class of compounds that have interesting pharmacological activities. They are derived from the same chemical group as aminoguanidine, so it has mixed properties (receptor and donor) in the formation of hydrogen bonds. Its anticancer agent properties were recently highlighted, but the molecules of this class have solubility in aqueous solutions that can be considered low. The identification of this class, by a simple, sensitive and low-cost technique, such as electrochemistry, which also allows the evaluation of its solubilization process through agents such as PAMAM dendrimer is the main objective of the work described here. The electrochemical response of the LQM10 (AGH derivative) was evaluated, as well as its behavior in different electrochemical sensors. Electrochemical experiments were performed in buffered (phosphate at pH 7.02 and acetate at 4.5). LQM10 has a reversible oxidation peak with a potential of +0.22 V. It was efficiently detected in different electrodes tested (glass carbon/CNT, glass carbon/CNT/PAMAM), which proves the viability of the electrodes for various analyses and has the determination of the apparent constant association, indicating its interaction with the analysis that is higher in the presence of the PAMAM encapsulating agent. This was corroborated by the results for the modified gold electrode with MUA and PAMAM. The sum of the results shows the possibility of electrochemically evaluating the Aminoguanidine hydrazone derivative, the viability of electrodes employed and the greater solubilization of LQM10 in the presence of the PAMAM dendrimer.

关键词： Drug Delivery Aminoguanidine Hydrazone Modified Electrode PAMAM

Osmotic Dehydration of Pineapple Stems in Hypertonic Sucrose Solutions

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Agricultural Sciences 2015年第9期6卷 916-924页

作者： Ronaldo dos Santos Falcao Filho Rennan Pereira de Gusmao Wilton Pereira da silva Josivanda palmeira Gomes Edvaldo Vasconcelos Carvalho Filho Anoar Abbas El-Aouar Federal Institute of Rio Grande do Norte Currais NovosBrazil Federal University of Campina Grande Campina GrandeBrazil Federal University of Rio Grande do Norte Santa CruzBrazil Federal University of Paraíba Joao PessoaBrazil

The present study provides the evaluation in the influence of the variables: temperature (T), concentration of the osmotic solution (C) and ratio of fruit and osmotic solution (F:OS) during the osmotic dehydration of slices of pineapple stem variety Perola, on the responses: water loss (WL), mass loss (ML), gain of solids (GS) and ratio of gain of solids and water loss (GS/WL). The centesimal composition was determined both in the raw material and in the dehydrated product. To optmize the process, the studied factors were: temperature (T), with factorial points -1 equal to 30°C and +1 equal to 50°C;concentration of sucrose solution (C), with factorial points -1 equal to 40 g·100 g-1 and +1 equal to 60 g·100 g-1 and ratio of fruit and osmotic dehydration solution (F:OS), with factorial points -1 and +1 equal to 1:20 and 3:20, respectively. In all essays, the dehydration time was 4 hours. The essays showed that F:OS was not significant in any responses;the models adopted were predictive and fitted for WL and ML, and reasonable for GS and GS/WL. The temperature was the most significant variable in the process;the optimized values were: T= 50°C, C = 40 g 100 g-1 e F:OS = 3:20. The product needs a complementary drying to adapt itself to the legislation demands.

关键词： Pineapple Dried Fruit Experimental Design

Homocysteine and Cardiovascular Risk Factors in Overweight or Obese Children and Adolescents

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Health 2015年第3期7卷 381-389页

作者： Adriana Amorim de Farias Leal Monica Oliveira da silva Simoes Alessandra Teixeira Carla Campos Muniz Medeiros Astrid Camelo palmeira Gabriella Menezes Almeida de Castro Mayara Larrys Gomes de Assis Maísa Soares de Oliveira Graduate Program in Public Health State University of ParaibaCampina GrandeBrazil Department of Pharmacy State University of ParaibaCampina GrandeBrazil Department of Nursing State University of ParaibaCampina GrandeBrazil Scientific Initiation Program State University of ParaibaCampina GrandeBrazil

Introduction: Among the extrinsic factors, homocysteine (Hy) stands out, which is an intermediate amino acid of the intracellular metabolism of methionine involved in the process of cellular oxidation, which promotes the installation of atheromatous plaques and, therefore, is considered as an emerging cardiovascular risk factor. Objective: To evaluate the plasma homocysteine levels (Hy) in overweight or obese children and adolescents and their relation with cardiovascular risk factors. Methods: A cross-sectional study was conducted from July 2011 to May 2012 with overweight or obesity children and adolescents aged 2 to 18 years followed at the Center for Childhood Obesity (IOC), Campina Grande-PB. A structured form was used to record demographic, socioeconomic and clinics variables and the patients underwent laboratory tests to define their lipid and glucose profiles and measurement of plasma Hy levels. Results: The study evaluated a total of 165 children and adolescents with mean age of 12.5 (±2.5) years;the majority were female (57.0%). Regarding the lipid profile, there was more individuals with low HDL cholesterol (88.5%). Plasma Hy levels were high in 24.2% of the sample. The mean Hy levels ranged from 4.3 to 18.9 μmol/L, being higher in males, obese adolescents and also in patients with high insulin levels and resistance. Conclusions: The results shown in this study emphasize the importance of detecting and controlling the plasma Hy levels as an independent cardiovascular risk factor, and the need for further studies to evaluate the clinical and biological factors related to alterations in its metabolism.

关键词： Homocysteine Cardiovascular Diseases Child Adolescent Obesity

Ex-Patients with COVID-19: Observations after Healing and Its Consequences*

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Open Journal of Epidemiology 2021年第1期11卷 31-36页

作者： José Humberto Cardoso Resende Aline Correia Barbosa Arley Braz Gomides daniel Asafe Ferreira Rocha Gabriela Costa Santos Helena Beatriz Gonç alves Pô rto Mariana palmeira Dias De Souza Rainy da silva Rogério Tágara Alessandra Oliveira Kamimura Emí dio silva Falcã o Brasileiro Alfredo Nasser University Aparecida de Goi&#226 nia GO Brazil

During the SARS-Cov-2 or COVID-19 clinical course pandemic of the coronavirus family, we observed symptoms of the respiratory tract, fever, cough, sore throat, and fatigue. The most common symptoms were loss of smell and taste and, when aggravated, it could develop into pneumonia and even death. We selected 40 former COVID-19 patients, who answered a questionnaire with questions about the symptoms and complications after they were cured and which symptoms remained or appeared after the total isolation quarantine for a specific time. Among the answers, the most cited was about “forgetting”. Another observation noted was the number of cases in children, which surprised us, considering that, at the beginning of the pandemic, the danger was more related to the elderly population and those with comorbidities.

关键词： Corona COVID Disease Infection Pandemic Pneumonia Thrombosis

Additional Records of the American Elephantfish <i>Callorhinchus callorynchus</i>(Chondrichthyes, Holocephali, Chimaeriformes) in Southeastern Brazil

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Natural Resources 2020年第10期11卷 439-445页

作者： Salvatore Siciliano Ana Rita O. palmeira-Nunes Getulio Rincon Jorge Luiz silva Nunes Sérgio C. Moreira Márcio L. V. Barbosa-Filho Laboratório de Biodiversidade Instituto Oswaldo Cruz/Fiocruz Rio de Janeiro RJ Brazil Grupo de Estudos de Mamíferos Marinhos da Regiã o dos Lagos (GEMM-Lagos) Araruama RJ Brazil Universidade Federal do Maranhã o (UFMA) Laboratório de Organismos Aquáticos Departamento de Oceanografia e Limnologia S&#227 o Luís MA Brazil Universidade Federal do Maranhã o (UFMA) Curso de Engenharia de Pesca Pinheiro MA Brazil Setor de Mamíferos Departamento de Vertebrados Museu Nacional/UFRJ Rio de Janeiro RJ Brazil Departamento de Ciências Biológicas Programa de Pós-gradua&#231 o em Etnobiologia e Conservaç o da Natureza Universidade Federal Rural de Pernambuco (UFRuPE) Campus Dois Irm&#227 os Recife PE Brazil

Chimaeras, fish in the order Chimaeriformes, are among the rarest and least studied fish in the class Chondrichthyes (cartilaginous fish). Previous records have indicated that a species of chimaera known as the elephantfish, or cockfish, Callorhinchus callorynchus, may be found in marine waters off southeastern Brazil, as far north as the state of São Paulo. Here we report that C. callorynchus, caught with bottom gillnet, was found in an urban fish market in the city of Rio de Janeiro (~23˚S). This and other records from a variety of places call into question the distribution limits of the American elephantfish in the southwestern Atlantic Ocean and whether, at least seasonally, this species may often be found as far north as the state of Rio de Janeiro. Because of scientific and conservation interests in the poorly known Chimaeriformes, we recommend long-term monitoring of the fish catch in ports along the southern Brazilian coast, to better understand the natural history of the intriguing chimeras.

关键词： Callorhinchus Callorynchus American Elephantfish Holocephali Chimaera Bycatch Southwest Atlantic Ocean