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Search Results: 1 - 10 of 225164 matches for " Julio Cézar Balarini "
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Solvent Extraction of Citric Acid with Different Organic Phases  [PDF]
Estêv?o Magno Rodrigues Araújo, Fabrício Eduardo Bortot Coelho, Julio Cézar Balarini, Tania Lúcia Santos Miranda, Adriane Salum
Advances in Chemical Engineering and Science (ACES) , 2017, DOI: 10.4236/aces.2017.73023
Abstract: The present work aimed at the study of citric acid solvent extraction in order to establish the composition of the organic phase and to obtain thermodynamic and kinetic data for the chosen system. Discontinuous extraction experiments in a single stage were performed from a synthetic solution of citric acid, with the typical concentration (10% w/v) observed in industrial fermented musts. Exploratory experiments were carried out using different organic phases in order to select the most suitable solvent phase to further continuous extraction tests in a mechanically agitated column. The selected organic phase composition was: Alamine 336, ExxalTM 13 tridecyl alcohol, and the aliphatic diluent EscaidTM 110. Next, the effects of the contact time and of the concentrations of extractant and modifier on the citric acid extraction were studied. Among the investigated conditions, the best one was 10 minutes of contact time, 30% w/v of Alamine 336, and 10% w/v of ExxalTM 13 tridecyl alcohol. For this condition, the equilibrium isotherm (28°C ± 2°C) was determined, and the equilibrium constant was calculated (36.8 (mol·L-1)-1.5). It was considered that trioctylamine and citric acid complexation reaction occurs mainly with non-dissociated citric acid form, because the aqueous feed solutions’ pH is lower than the citric acid pKa1. It was found that 1.5 molecules of the extractant, on average, are required to react with one citric acid molecule, which can indicate that reactions with different extractant/citric acid ratios occur simultaneously. Next, the rate constants for the direct and inverse reactions, 2.10 (mol·L-1)-1.5·s-1 and 5.69 × 10-2 s-1, respectively, were calculated. Coefficients of determination (R2) values higher than 0.93 were found in these calculations, suggesting that the results obtained using a computer modeling would be very close to those results obtained experimentally. Therefore, the present work provides data required to future modelling, design, and simulation of citric acid solvent extraction processes.
Individual and Combined Effects of the Extractant, Surfactant and Modifier Concentrations on the Droplet Coalescence Time of the Primary Emulsion in the Liquid Surfactant Membrane Extraction Process  [PDF]
Adriane Salum, Lorena da Costa Nascimento, Tania Lúcia Santos Miranda, Leandro Dornellas Sampaio Andrade, Cibele Konzen, Julio Cézar Balarini, Estêv?o Magno Rodrigues Araújo, Fabrício Eduardo Bortot Coelho
Advances in Chemical Engineering and Science (ACES) , 2018, DOI: 10.4236/aces.2018.84014
Abstract: In this work, the individual and combined effects of the extractant, surfactant and modifier concentrations on the droplet coalescence time of the primary emulsion in the liquid surfactant membrane extraction process were evaluated, through emulsification experiments. Adogen 464 was used as extractant (carrier), and Escaid 110, as diluent. Two systems were studied. The first one composed by the extractant, the surfactant and the diluent, and the second one composed by the same reagents, but with the addition of 1-decanol as modifier. It was observed that, when the modifier is not present in the membrane phase, the surfactant not only stabilizes the primary emulsion, but, apparently, it also plays a role similar to that of the alcohol, promoting the solvation of the amine in a low polarity diluent. Furthermore, the extractant, a quaternary amine, helps to stabilize the primary emulsion in systems without a modifier. For membrane phases consisting of 1 or 5% w/w of Adogen 464 and 2% or 5% w/w of ECA 4360, a concentration of 3% w/w of 1-decanol was sufficient to promote the solvation of Adogen 464 in Escaid 110 and to obtain a low droplet coalescence time.
Julio Cézar Silveira Nunes,Paulo Mar?al Fernandes
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v30i2.2579
Abstract: This work studied the indexes of parasitism of A. grandis in floral buttons of the cotton plants, collected in the soil and in the plants, in an area not treat with insecticides, located in the School of Agronomy of the Universidade Federal de Goiás, municipal district of Goiania-GO. Floral buttons were collected with and without sign of oviparousness of the beaked ones. They presented larger parasitism occurrence in those collected in the soil. The parasites were identified as: Chelonus sp. (Microchelonus), Bracon sp. and Pteromalidae. KEY-WORDS: Insecta; parasitism; cotton plant; Anthonomus grandis. Estudou-se o índice de parasitismo de A. grandis em bot es florais de algodoeiro coletados no solo e nas plantas, em uma área n o tratada com inseticidas, localizada na Escola de Agronomia da Universidade Federal de Goiás, no município de Goiania (GO). Foram coletados bot es florais com e sem puncturas de oviposi o dos bicudos. Verificou-se um maior parasitismo nos bot es florais coletados no solo. Os parasitóides foram identificados como Chelonus sp. (Microchelonus), Bracon sp. e Pteromalidae. PALAVRAS-CHAVE: Insecta; parasitismo; algodoeiro; Anthonomus grandis.
Capacidad para las actividades de la vida diaria en las personas mayores que acudieron a centros de convivencia en Zaragoza capital en 2005
Lázaro Alquézar,Angelina; Rubio Aranda,Encarnación; Sánchez Sánchez,Antonio; García Herrero,Julio César;
Revista Espa?ola de Salud Pública , 2007, DOI: 10.1590/S1135-57272007000600006
Abstract: background: to study the dependence related to aging is of particular interest in aragon, where the population is one of the most aged in spain. the objective of this study is that of quantifying the degree of functional dependence for daily living activities (dla) and identifying the personal traits related thereto among individuals age 65 and above who are living at home and attend community centers in the city of zaragoza. methods: cross-sectional study with 380 individuals selected by two-stage sampling. the oars-mfaq questionnaire was used by way of personal interviews, analyzing questions which assess the functional capacity to carry out the dla?s and their scoring (dependent variable), sociodemographic variables, self-assessed health condition and actual and hypothetical informal help (independent variables). the chi-square was used for evaluating classified residual data (p<0.05) and multiple correspondence analyses. results: a total of 9.6% of the subjects showed "major/total dependence", this percentage increasing to 15.5% and 18.7% for those individuals above age 75 and 80, respectively. the "minor/moderate dependence" is related to being a female (p<0.01), health condition self-assessed as poor-passable (p<0.0001), being a widow(er) (p<0.01), having no elementary school education (p<0.01). conclusions: those individuals who are more elderly, females, widow/widowers, having a lesser degree of education and worse self-assessed health condition are more dependent. practically one out of every ten non-institutionalized individuals 65 years of age or over shows a severe deterioration of their functional capacity. extrapolating, nearly 11,000 individuals in the city of zaragoza would require daily help for the dla?s or should stay institutionalized.
Detec??o da encefalopatia hepática subclínica por espectroscopia cerebral
Schulz, Gustavo Justo;Coelho, Julio Cézar Uili;Matias, Jorge Eduardo Fouto;Campos, Ant?nio Carlos Ligocki;Schulz, Danielle Duck;Bertoldi, Guilherme Augusto;
ABCD. Arquivos Brasileiros de Cirurgia Digestiva (S?o Paulo) , 2007, DOI: 10.1590/S0102-67202007000200003
Abstract: background: hepatic encephalopathy is a common neuro-psychiatric abnormality in liver cirrhosis associated with typical changes of cerebral metabolite pattern, such as a decrease of myo-inositol and cholina and increase of glutamine-glutamate, observed by magnetic resonance spectroscopy. aim: to determine cerebral metabolite ratios in liver cirrhosis patients with early stages of hepatic encephalopathy. methods: twenty-five patients with chronic hepatic failure from liver transplantation unit of the federal university of paraná were studied with clinical evaluation and magnetic resonance spectroscopy. localized magnetic resonance spectra were acquired in the occipital gray/white matter regions. thirty healthy volunteers were also subjected to the same evaluations, making up the control group. results: subclinical hepatic encephalopathy was diagnosed in 12 patients (48%). mi/cr ratios were significantly reduced in cirrhotic patients with hepatic encephalopathy when compared to the control group (0,49±0,10 vs. 0,83±0,13; p < 0,0001). in addition, patients with encephalopathy, showed reduction of the cho/cr ratio (0,54±0,15 vs. 0,77±0,09; p = 0,0001) and an elevated glx/cr ratio (1,12±0,26 vs. 0,89±0,19; p = 0,0146). the ross's quantitive criterions for spectroscopic diagnoses of hepatic encephalopathy (mi/cr and cho/cr below than 2 sd of controls) demonstrated a sensibility of 61,54%, specificity of 91,67% and accuracy of 76%. cho/cr ratio was considered the best parameter. conclusion: cerebral metabolic alterations that occur at an early stage of hepatic encephalopathy may be demonstrated through magnetic resonance spectroscopy, allowing a precise diagnosis before the appearance of clinical signs and symptoms.
Espectroscopia cerebral em candidatos a transplante hepático
Schulz, Gustavo Justo;Coelho, Julio Cézar Uili;Matias, Jorge Eduardo Fouto;Campos, Ant?nio Carlos Ligocki;Schulz, Danielle Duck;Bertoldi, Guilherme Augusto;
Revista da Associa??o Médica Brasileira , 2009, DOI: 10.1590/S0104-42302009000100012
Abstract: objectives: to determine the metabolite levels (myo-inositol [mi], choline [cho], glutamate [glx], creatine [cr] and n-acetylaspartate [naa]) visible on magnetic resonance spectroscopy in patients with chronic hepatic failure, before and after liver transplantation and to correlate these data with results of neuropsychiatric tests and clinical findings. methods: twenty five patients with chronic hepatic failure from the liver transplantation unit of the federal university of parana were prospectively studied. patients were submitted to clinical evaluation and magnetic resonance spectroscopy. thirty healthy volunteers also submitted to the same evaluations. sixteen of the 25 patients were evaluated after liver transplantation. results: before liver transplantation, significant reductions in mi/cr and cho/cr and a significant increase in glx/cr were observed in patients with hepatic encephalopathy compared with healthy subjects. the ross's criteria for spectroscopic diagnosis of the hepatic encephalopathy (mi/cr and cho/cr lower than 2 sd of controls) demonstrated a sensitivity of 61.54%, specificity of 91.67% and accuracy of 76%, further cho/cr was the best parameter. spectroscopy after liver transplantation showed changes in the metabolite ratios compared with the pretransplantation status. conclusion: magnetic resonance spectroscopy permits an accurate diagnosis of hepatic encephalopathy. improvement of metabolic ratios after liver transplantation suggests an important role of mi and cho in the development of hepatic encephalopathy.
Quality in Higher Education: From the Diversity of Conceptions to the Relentless Conceptual Subjectivity  [PDF]
Julio C. G. Bertolin
Creative Education (CE) , 2015, DOI: 10.4236/ce.2015.622247
Abstract: The current article approaches and assesses the different conceptions and understandings of quality in the higher education scope. Initially, the text reviews the concepts of quality based on the taxonomies presented by the top researchers approaching this subject; next, it shows a list of terms that have been recently identified according to the views of quality in higher education, such as economic competitiveness and market growth, sustainable sociocultural and economic development or, yet, to a view of higher education that has the prior mission of social cohesion and equity. Finally, the relentless conceptual relativity of quality in the higher education is approached.
Complica??es oculares da terapêutica com a cloroquina e derivados
Lacava, Augusto Cézar;
Arquivos Brasileiros de Oftalmologia , 2010, DOI: 10.1590/S0004-27492010000400019
Abstract: introduction: byproducts of 4-aminoquinolones are being used since its industrialization in the treatment of malaria, rheumatic and dermatologic diseases. these drugs present systemic and ocular adverse events. systemic adverse reactions affect the gastrointestinal, nervous and skeletal muscular systems and the skin. ocular adverse reactions are: photophobia, cornea verticillata, poliosis, cataract, extraocular muscle palsy, anterior uveitis, toxic maculopathy and optical neuritis. purpose: bibliography review of complications due to the use of chloroquine and its derivatives. to analyze the current practice and propedeutics' evolution. to suggest practical managements for early toxicity signs. methods: bibliographic review through research on medline, pubmed, lilacs and scielo database. discussion: all exams that can be used to screen ocular adverse reactions are described, such as: complete ophthalmologic exam, with emphasis on biomicroscopy and indirect binocular ophthalmoscopy, computerized visual field, amsler grid testing and color vision testing, electrophysiological exams, polarimetry and optical coherence tomography. a description of maculopathy is presented, focusing on epidemiology, risk factors, histopathology and propedeutics. chemical structure and the differences between 4-aminoquinolone derivatives are described. conclusion: all patients using chloroquine and its derivatives must be followed-up and documented since the beginning of the therapy until they reach a cumulative dose above 100 grams. the higher the cumulative dose, the more we must be concerned with patient follow-up.
C. Zar,P. Botez
Jurnalul de Chirurgie , 2009,
Abstract: Osteonecrosis of the femoral head (ONFH) is a disabling condition that affects mainly young subjects (average age 33-38 years old); to this day, it has remained a devastating disease. Osteonecrosis may be defined as the death of the cell components of bone - both osteocytes and bone marrow cells. ONFH is not a specific entity, but the final common pathway of various conditions that impair the blood supply to the femoral head - hence the frequently used term avascular necrosis. Surgical technological advancements have improved outcomes for these patients. However, due to the relatively young age of onset, these patients are often subjected to multiple operative procedures during their lifetime. Differential diagnosis should be made with: pigmented villonodular synovitis; idiopathic transient osteoporosis of the hip; stress fractures of femoral neck; metastastic bone carcinoma.
Los recursos humanos en un espacio natural protegido: Sierra Nevada
Ma. Enriqueta Cózar
Cuadernos Geográficos , 2000,
Abstract: Sierra Nevada, como todas las áreas de monta a espa olas y gran parte del territorio interior andaluz, ha experimentado durante el siglo XX un considerable retroceso demográfico. La población con la que llega al umbral del siglo XXI es una cuarta parte más peque a que la registrada en 1900 y un tercio inferior a la de 1950. Diversos y complejos factores, tanto internos como externos al área de monta a, de carácter más económico que demográfico, fueron los desencadenantes de una fuerte emigración. La gran pérdida de población ha originado cambios trascendentales en la demografía y en la actividad económica de Sierra Nevada. En la actualidad, la población de este espacio protegido se caracteriza por una desequilibrada distribución en el territorio, un escaso crecimiento natural, un acelerado envejecimiento y una actividad mayoritariamente terciaria. La declaración, en Julio de 1989, como espacio natural protegido bajo la figura de Parque Natural, y la más reciente de Parque Nacional, apenas ha modificado la inercia demográfica regresiva de la mayor parte de sus municipios; tan sólo se ha podido apreciar una cierta tendencia a la estabilización demográfica de la población total del macizo
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