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Search Results: 1 - 10 of 251677 matches for " Roberta dos R Ribeiro "
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Optimización de la Concentración de L-Cisteína para la producción de 1,3-Propanodiol por una vía Biotecnológica
Ferreira,Tatiana F; Ribeiro,Roberta dos R; Matos,Pedro M; Coelho,Maria Alice Z;
Información tecnológica , 2013, DOI: 10.4067/S0718-07642013000100006
Abstract: glycerol was converted into 1,3-propanediol (1,3-pdo) using citrobacter freundii atcc 8090. 1,3-pdo is a bifunctional molecule that can be used in many applications, being of great commercial interest. the most recent route used for the production of this compound is through biotechnology using some micro-organisms capable of anaerobically converting glycerol into 1,3-pdo. the conversion done makes it necessary the addition of cysteine ??to the culture medium. five experiments were performed with cysteine at five concentrations to verify which is the optimum concentration that does not affect conversion of glycerol into 1,3-pdo. the concentrations used were 0.05, 0.10, 0.15, 0.20 and 0.25 gl-1. the yields were 15, 20, 26, 35 and 28 % respectively. according to the results it is concluded that the optimum cysteine concentration ??for 1,3-pdo production is 0.20 g.l-1.
Optimización de la Concentración de L-Cisteína para la producción de 1,3-Propanodiol por una vía Biotecnológica Optimization of L-Cysteine Concentration to produce 1,3-Propanediol by a Biotechnological route
Tatiana F Ferreira,Roberta dos R Ribeiro,Pedro M Matos,Maria Alice Z Coelho
Información Tecnológica , 2013,
Abstract: Se ha realizado la conversión de glicerol en 1,3-propanodiol (1,3-PDO) usando la cepa Citrobacter freundii ATCC 8090. El 1,3-PDO es una molécula bifuncional que puede ser utilizada para muchas aplicaciones, siendo así de gran interés comercial. Una ruta más reciente para la producción de este compuesto es la vía biotecnológica utilizando algunos microorganismos capaces de convertir anaeróbicamente glicerol en 1,3-PDO. La conversión realizada hace necesaria la adición de cisteína al medio de cultivo. Se realizaron cinco experimentos con cinco concentraciones de cisteína con el fin de verificar cuál es la menor concentración posible que no afecta la conversión de glicerol en 1,3-PDO. Las concentraciones utilizadas fueron 0,05; 0,10; 0,15; 0,20 y 0,25 g.L-1. Los rendimientos fueron 15, 20, 26, 35 y 28 % respectivamente. De acuerdo a los resultados se concluye que la concentración óptima de cisteína para la producción de 1,3-PDO es 0,20 g.L-1. Glycerol was converted into 1,3-propanediol (1,3-PDO) using Citrobacter freundii ATCC 8090. 1,3-PDO is a bifunctional molecule that can be used in many applications, being of great commercial interest. The most recent route used for the production of this compound is through biotechnology using some micro-organisms capable of anaerobically converting glycerol into 1,3-PDO. The conversion done makes it necessary the addition of cysteine to the culture medium. Five experiments were performed with cysteine at five concentrations to verify which is the optimum concentration that does not affect conversion of glycerol into 1,3-PDO. The concentrations used were 0.05, 0.10, 0.15, 0.20 and 0.25 gL-1. The yields were 15, 20, 26, 35 and 28 % respectively. According to the results it is concluded that the optimum cysteine concentration for 1,3-PDO production is 0.20 g.L-1.
Electrochemical Investigation of Corrosion on AISI 316 Stainless Steel and AISI 1010 Carbon Steel: Study of the Behaviour of Imidazole and Benzimidazole as Corrosion Inhibitors  [PDF]
Roberta R. Moreira, Thiago F. Soares, Josimar Ribeiro
Advances in Chemical Engineering and Science (ACES) , 2014, DOI: 10.4236/aces.2014.44052
Abstract: An electrochemical investigation of the corrosion on AISI 316 austenitic stainless steel and AISI 1010 carbon steel in sodium chloride solution (3.0 wt.%) was performed in the absence and presence of imidazole and benzimidazole corrosion inhibitors. The results showed that at any inhibitor concentration (25 ppm to 1000 ppm), there was an increase in the polarisation resistance of both steels. The highest efficiency of corrosion inhibition was obtained using imidazole at a concentration of 50 ppm for both steels, with values of 96% for the AISI 316 stainless steel and 73% for the AISI 1010 carbon steel.
Study of microbial flora aclimatization to increasing concentrations of efluents “in natura” of the industry of fishing in reactors of sequential batch
Roberta R. Ribeiro,Daniela P. Mesquita,Maria Alice Z. Coelho
Engenharia Ambiental : Pesquisa e Tecnologia , 2009,
Abstract: The present work analyzes the adaptation and activity of a sludge belonging to a UASB reactor of the wastewater treatment unit from a fish processing industry, in a bench scale Sequencing Batch Reactor for biological nitrogen removal. The sludge adaptation was carried using an increasing sequence of the applied load from 1:3.33; 1:2.5; 1:2.0; regarding to volume of in natura wastewater : synthetic sewage. The initial inocullum concentration employed was 20 g VSS / L. During this period COD, nitrate and ammonia concentrations were followed and a removal about 80% of the organic matter and up to 97% of nitrogen could be achieved. An experiment employing the greater dilution (1:3.33) with 0.5% salt (as NaCl) was also carried to evaluate the salinity effect which is considered in the analysis of the results herein presented.
Seroprevalence of Cutaneous Leishmaniasis (LC) in dogs and identification of vectors (Diptera:Psychodidae) in Bela Vista do Paraíso, Parana state Soroprevalência da Leishmaniose Tegumentar Americana (LTA) canina e fauna de Flebotomíneos (Diptera: Psychodidae) em Bela Vista do Paraíso, Paraná
Homero Ribeiro dos Reis,Fabiana Maria Ruiz Lopes-Mori,Célia Rosimarie dos Reis,Roberta Lemos Freire
Semina : Ciências Agrárias , 2011,
Abstract: The aim of this study was to determine the seroprevalence of Cutaneous Leishmaniasis (CL) in dogs of Bela Vista do Paraiso, Parana state, compare the IFA and ELISA techniques and identify the vectors possibly involved in the cycle of the parasite. Were collected blood samples from 489 dogs that were subjected to detection of anti-Leishmania sp. by IFA and by ELISA. Were considered positive samples 340 titers in IFA and for ELISA 3 0.174 optical density. Among the samples analyzed, 222 (45.4%) were positive by IFA and 189 (38.7%) by ELISA. Comparing the tests were found 176 positive samples (36.0%) and 254 negative (51.9%) for both techniques. The sensitivity of ELISA was 79.3% and specificity was 95.1%. The global coefficient of the test was 87.0% with kappa coefficient of 0.75. Analysis of variables for dogs with positive serology by IFA showed significant differences regarding the absence of forests and lack of contact with other animal species. Positive sera by ELISA in dogs variables that showed significant differences were the type of riparian vegetation existing in the environment, the lack of garbage, open sewers and released directly into rivers or streams and garbage thrown on wasteland, burned or buried. The result obtained with the capture of sandflies was the predominance of Lutzomyia whitmani with 79.9% of the species collected. The result obtained with the capture of sandflies was the predominance of Lutzomyia whitmani with 79.9% of the species collected. The results showed that the LTA is widespread in the canine population of Bela Vista do Paraiso, and both the IFI and ELISA can be used for diagnosis. So the dog appears as a link between wild and peridomestic cycle of CL may become an amplifier of disease in this ecosystem. O trabalho teve como objetivo determinar a soroprevalência da Leishmaniose Tegumentar Americana (LTA) canina no município de Bela Vista do Paraíso, Paraná, comparar as técnicas de imunofluorescência indireta (IFI) e ensaio imunoenzimático (ELISA) e identificar as espécies de flebotomíneos presentes, possivelmente envolvidas no ciclo do parasito. Amostras de sangue de 489 c es foram submetidas à pesquisa de anticorpos anti-Leishmania sp. pela IFI e ELISA. Foram consideradas positivas as amostras que apresentaram título 3 40 na IFI e densidade ótica 3 0.174 no ELISA. Entre as amostras analisadas, 222 (45,4%) foram reagentes pela IFI e 189 (38,7%) pelo ELISA. Comparando-se os testes foram encontradas 176 amostras positivas (36,0%) e 254 negativas (51,9%) para ambas as técnicas. A sensibilidade do ELISA foi de 79,3% e a es
Enzimas de fun??o hepática na aflatoxicose aguda experimental em frangos de corte
Borsa, Adriana;Lopes, S?nia Terezinha dos Anjos;Santurio, Janio Morais;Mallmann, Carlos Augusto;Lopes, Juarez Morbini;Fernandes, Roberta Ribeiro;
Ciência Rural , 1998, DOI: 10.1590/S0103-84781998000400009
Abstract: the aim ofthis study is to evaluate ?he hepatic function of experimentally intoxicated broilers by aflatoxin with and without sodium bentonite. forty ross mole broilers, were used divided into 4 groups of 10 birds, and such groups have been submitted to the following treatments: t1- control (feed without aflatoxin or sodium bentonite), t2- feed containing 5ppm of aflatoxin, t3- feed containing 5ppm of aflatoxin and 0.5% of sodium bentonite and t4- feed containing 0.5% of sodium bentonite. ali these treatments have been appiied from the lst to the 42nd day of lif e. on the days 21, 35 and 42, the serum leveis of the enzimes aspartate aminotransferase (ast), alanino aminotransferase (alt), lactate dehydrogenase (ldh) and gamma glutamiltransferase (ggt). the analysis of variance showed an interaction between treatments and time of blood sampling for the following variables: ast, ldh and ggt. tukey test was used to compare significant averages among treatments. it was observed that the enzimes ast, alt and ggt have not shown significam diferences among treatments. however, in treatment 2, ast showed a linear increase (p < 0.01) along the experiment, more pronounced in treatment 2. the alt had no variation in any treatment during the total period. the ggt enzyme in treatments 2 and 3 had a linear increase (p < 0.05) for ali periods. the ldh leveis, at the 21st day, was higher for treatments 2 and 3 compared to treatments l and 4. according to the results, it can be concluded that is possible to detect the hepatotoxicity of aflatoxin in through monitoring of enzimes ast and ggt leveis, in the serum of birds between 21 and 42 days of age, and by evaluation ofldh at 21 days.
Mecanoterapia e fortalecimento muscular: um embasamento seguro para um tratamento eficaz
Ana Paula T. Lima,Itatiara Alves Ribeiro,Leda Maria de Castro Coimbra,Monique Roberta N. dos Santos
Revista Saúde.Com , 2006,
Abstract: Trata-se de um estudo sobre a eficácia dos dispositivos mecanicos fisioterapêuticos no ganho de for a, mediante uma fundamenta o fisiológica e biomecanica associado a correla es clínicas. A metodologia utilizada reporta-se a uma revis o bibliográfica através da verifica o e compara o de textos de livros e artigos de revistas científicas. Apesar do sucesso de um plano de fortalecimento muscular ter uma rela o intrínseca com um embasamento teórico conciso, a bibliografia disponível que correlaciona mecanoterapia e fortalecimento muscular é escassa e as informa es, muitas vezes, s o fragmentadas. Assim este trabalho possibilitou a listagem dos dispositivos mecanicos, fornecendo dados que podem ser úteis para a realiza o de futuros estudos clínicos.
Effect of solvent on the preparation and characterization of DSA?-type anodes containing RuO2-TiO2-SnO2
Coteiro, Roberta D.;Teruel, Fernando S.;Ribeiro, Josimar;Andrade, Adalgisa R. de;
Journal of the Brazilian Chemical Society , 2006, DOI: 10.1590/S0103-50532006000400020
Abstract: anodes containing ruthenium, titanium, and tin oxides supported on metallic ti were prepared by thermal decomposition of precursor salts in order to investigate the effect that changing the solvent (from hcl/h2o to isopropanol) would have on the real composition of the mixed oxide electrodes. the precursor solutions and their mixtures were analyzed by uv-vis spectrophotometry. coatings morphology and composition were analyzed by scanning electronic microscopy (sem) and energy dispersive x-ray (edx). determination of the electrochemically active area and electrode stability was performed by voltammetric characterization (1.0 mol l-1 hclo4) and service life (sl) tests, respectively. electrodes prepared from isopropanol showed excellent agreement between the nominal and experimental composition and they presented higher electrochemically active area and better stability when compared to those prepared in the presence of hcl. preparation of the precursor mixture in isopropanol increases ruo2-tio2-sno2 electrodes service life.
Dos potenciais evocados miogênicos vestibulares nas orelhas comprometida e assintomática na Doen?a de Ménière unilateral
Ribeiro, Súnia;Almeida, Roberta R. de;Caovilla, Heloisa H.;Ganan?a, Maurício M.;
Revista Brasileira de Otorrinolaringologia , 2005, DOI: 10.1590/S0034-72992005000100011
Abstract: aim: to verify whether vestibular evoked myogenic potentials can present abnormalities in the affected ear and in the asymptomatic ear in patients with diagnosis of unilateral ménière's disease. study design: transversal cohort. material and method: the vestibular evoked myogenic potentials of 20 patients with unilateral ménière's disease were analyzed. the selection of individuals was based on the history and in clinical evaluation suggestive of unilaterally defined ménière's disease, and with electrocochleography abnormalities in the affected ear. vestibular evoked myogenic potentials were evaluated in both ears of each patient through absolute latencies of p13 and n23, interaural difference of latency of peaks p13 and n23 and amplitude p13-n23 asymmetry rate. results: vestibular evoked myogenic potentials were altered in 35.0% of the affected ears and in 25.0% of the asymptomatic ears. the alterations were: absence of responses in seven cases, prolongation of p13 latency in three cases, and increase in interaural amplitude difference ratio in one case. conclusion: the vestibular evoked myogenic potentials can present abnormalities in the affected and asymptomatic ears in patients with diagnosis of unilaterally defined ménière's disease.
Metals Complexes Formed with Oleanolic Acid  [PDF]
Nilton C. Ribeiro, Antonio J. Demuner, Marcelo H. dos Santos, Célia R. A. Maltha, Elson A. de Alvarenga, Slavko Komarnytsky
International Journal of Organic Chemistry (IJOC) , 2018, DOI: 10.4236/ijoc.2018.81011
Abstract: The oleanolic acid possesses diverse pharmacological properties, it is considered as a good starting material for creating new compounds. The oleanolic acid isolated of Plumeria obtusa leaves was used as raw material to obtained calcium, magnesium, zinc, nickel and copper complexes. The structures of complexes were confirmed by HRMS, 1H NMR, and 13C NMR. Five new compounds were synthesized to promote increased biological activity of oleanolic acid and PCR assays for the different type of cancer.
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