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Search Results: 1 - 10 of 91179 matches for " Regina da Silva;Garcia "
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Predicting of the Fibrous Filters Efficiency for the Removal Particles from Gas Stream by Artificial Neural Network  [PDF]
érica Regina Filletti, Juliana Maria da Silva, Valdemir Garcia Ferreira
Advances in Chemical Engineering and Science (ACES) , 2015, DOI: 10.4236/aces.2015.53033
Abstract: In this paper, artificial neural networks are used for predicting single fiber efficiency in the process of removing smaller particles from gas stream by fiber filters. For this, numerical simulations are obtained of a classic model of literature for fiber efficiency, which is numerically solved along with the convection diffusion equation in polar coordinates for particle concentration, with associated initial and boundary conditions. A sufficient number of examples from two numerical simulations are employed to construct a database, from which parameters of a novel neural model are adjusted. This model is constructed based on the back propagation algorithm in order to map two features, namely Peclet number and packing density, which are extracted from the numerical simulations into the corresponding single fiber efficiency. The results indicate that the developed neural model can be trained in a reasonable computational time and is capable of estimating single fiber efficiency from examples of the test set with a maximum error of 1.7%.
Analysis of transient otoacoustic emissions and brainstem evoked auditory potentials in neonates with hyperbilirubinemia
Silva, Daniela Polo Camargo da;Martins, Regina Helena Garcia;
Brazilian Journal of Otorhinolaryngology , 2009, DOI: 10.1590/S1808-86942009000300013
Abstract: hyperbilirubinemia is toxic to the auditory pathways and to the central nervous system, leaving sequelae such as hearing loss and encephalopathy. aim: to assess the hearing of neonates with hyperbilirubinemia, using transient evoked otoacoustic emissions (toaes) and brainstem evoked auditory potentials (beap). prospective study. materials and methods: we had two groups: gi (n-25), neonates with hyperbilirubinemia; gii (n-22), neonates without hyperbilirubinemia and without risk factors for hearing loss. all the neonates had up to 60 days of life and were submitted to toae and beap. results: 12 neonates from gi and 10 from gii were girls and 13 from gi and 12 from gii were boys. toaes were present in all the children, however with lower amplitudes in gi, especially in the frequencies of 2 and 3khz (p < 0.05). regarding the beap, we observed a mild pv and li-v increase in bi. the alterations observed in these tests do not correlate to the serum levels of bilirubin. conclusions: in neonates with hyperbilirubinemia, we noticed lower toae amplitudes and mild pv and li-v increase, indicating cochlear and retrocochlear disorders, stressing the importance of using both tests and carefully reading them in these evaluations.
Larvicidal activity of oil-resin fractions from the Brazilian medicinal plant Copaifera reticulata Ducke (Leguminosae-Caesalpinoideae) against Aedes aegypti (Diptera, Culicidae)
Silva, Heloísa Helena Garcia da;Geris, Regina;Rodrigues Filho, Edson;Rocha, Cleonice;Silva, Ionizete Garcia da;
Revista da Sociedade Brasileira de Medicina Tropical , 2007, DOI: 10.1590/S0037-86822007000300002
Abstract: oil-resin fractions from copaifera reticulata ducke (leguminosae-caesalpinoideae) were evaluated for larvicidal activity on third larval instars of aedes aegypti, in searching for alternative control methods for this mosquito. the bioactive fractions were chemically monitored by thin-layer chromatography, 1h and 13c nuclear magnetic resonance and mass spectrometry. bioassays were performed using five repetitions, at a temperature of 28 ± 1°c, relative humidity of 80 ± 5% and light and dark cycles of 12h. mortality was indicated by darkening of the cephalic capsule after 24h of exposure of the larvae to the solutions. the most active fractions were crm1-4 (sesquiterpenes) and crm5-7 (labdane diterpenes), which showed lc50 values of 0.2 and 0.8ppm, respectively.
Atividade larvicida de taninos isolados de Magonia pubescens St. Hil. (Sapindaceae) sobre Aedes aegypti (Diptera, Culicidae)
Silva Heloísa Helena Garcia da,Silva Ionizete Garcia da,Santos Regina Maria Geris dos,Rodrigues Filho Edson
Revista da Sociedade Brasileira de Medicina Tropical , 2004,
Abstract: Apresenta-se, pela primeira vez, o estudo fitoquímico das fra es larvicidas, isoladas da Magonia pubescens, monitorado pelo estudo de eficácia sobre larvas de 3o estádio de Aedes aegypti, na busca de alternativas para o controle desse mosquito e obten o de estruturas químicas passíveis de aprimoramento da atividade pela via sintética de outros derivados. As fra es bioativas foram monitoradas quimicamente através de cromatografia de camada delgada, utilizando como revelador uma solu o ácida de vanilina, e analisadas por ressonancia magnética nuclear de hidrogênio e espectrometria de massas. Os bioensaios com as fra es foram realizados em quintuplicata, à temperatura de 28±1oC, 80±5% de umidade relativa e fotofase de 12 horas. As concentra es letais encontradas da fra o MP-9, que apresentou o maior potencial larvicida, CL50 e CL90, foram de 3,1 e 36,6ppm, respectivamente. Todos os experimentos foram acompanhados por uma série controle, contendo o mesmo número de larvas.
Biologia e exigências térmicas de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) sobre ovos de Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae)
Borba, Regina da Silva;Garcia, Mauro Silveira;Kovaleski, Adalécio;Comiotto, Andressa;Cardoso, Renata Loureiro;
Ciência Rural , 2006, DOI: 10.1590/S0103-84782006000500001
Abstract: this work was aimed at studyng the biology of trichogramma in laboratory, in search of its use in integrated management programs to control bonagota cranaodes in culture of the apple. the biology of trichogramma bruni nagaraja and of two lineages (l3 and l4) of trichogramma pretiosum on eggs of b. cranaodes was done such their thermal demands and annual number of generations. the line l3 presented more parasitism (52.3%), however, the feseability was similar among the lineages studied; with biological cycle of 8.7 days; the longevity of females was 10.65 days; low threshold temperature of 11.35°c and thermal requirement of 128.70 gd, the number of annual generations this line in laboratory was 47.22 and 13.59 for vacaria-rs climate conditions. the low parasitism of the t. bruni and of the lineage l4 of t. pretiosum can be related to the layer of secretion presented on the laying of the pest. although this parasitism is considered low, the use of these lineages cannot be discarded the integrated apple production, systens. new studies shal be accomplished in field conditions.
Technological functional properties of soy, oat and wheat fibers and soy products with added fibers and fermented with kefir culture Propriedades funcionais tecnológicas das fibras de soja, aveia e trigo e produtos de soja com adi o de fibras e fermentados com cultura de kefir
Tahis Regina Baú,Letícia Cardoso da Silva,Sandra Garcia,Elza Iouko Ida
Semina : Ciências Agrárias , 2012,
Abstract: The objective of this study was to characterize the technological functional properties of soy, oats and wheat fibers and evaluate soy products with added fiber and fermented with kefir. The fibers were characterized with regard to pH, water adsorption capacity, water and oil absorption capacity and swelling volume. Soy products were developed with the addition of 3% soy fiber, oat and wheat and fermented with kefir. The fermented products were characterized for pH, acidity, syneresis, viscosity and firmness, Lactococcus lactis counts and analysis of sanitary conditions. The soy fiber showed a higher content of protein and lipids, pH, water adsorption and adsorption capacity. The wheat fiber showed a higher oil absorption capacity. The addition of soy, oat and wheat fibers influence pH, acidity, syneresis, viscosity and firmness of fermented soy products with kefir. The lowest syneresis and highest viscosity and firmness were obtained with the soy fermented products with soy fiber. The addition of soy fiber stimulated Lactococcus lactis growth. The fermented soy products had enough Lactococcus lactis counts to be considered probiotics. The products presented satisfactory hygienic sanitary conditions. O objetivo deste trabalho foi caracterizar as propriedades funcionais tecnológicas das fibras de soja, aveia e trigo e avaliar os produtos de soja com adi o de fibras e fermentados com cultura de kefir. As fibras foram caracterizadas quanto a composi o química, pH, capacidade de adsor o e absor o de água, capacidade de absor o de óleo e volume de intumescimento. Foram desenvolvidos produtos de soja com adi o de 3% de fibra de soja, aveia e trigo e fermentados com cultura de kefir. Os produtos fermentados foram caracterizados quanto o pH, acidez, sinerese, viscosidade e firmeza, contagem de Lactococcus lactis e análise das condi es higiênico-sanitárias. A fibra de soja apresentou maior teor de proteínas e lipídios, pH, capacidade de adsor o e adsor o de água. A fibra de trigo apresentou maior capacidade de absor o de óleo. A adi o de fibras de soja, aveia e trigo influenciaram o pH, acidez, sinerese, viscosidade e firmeza dos produtos de soja fermentados com kefir. A menor sinerese e maior viscosidade e firmeza foram obtidos para os produtos fermentados com fibra de soja. O crescimento de Lactococcus lactis foi favorecido no produto fermentado com adi o de fibra de soja. Por conterem suficiente contagem, ou seja, acima de 6 log UFC.g-1 de Lactococcus lactis, os produtos fermentados podem ser considerados probióticos. Os produtos apresentaram cond
Biologia e exigências térmicas de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) sobre ovos de Bonagota cranaodes (Meyrick) (Lepidoptera: Tortricidae)
Borba Regina da Silva,Garcia Mauro Silveira,Kovaleski Adalécio,Comiotto Andressa
Ciência Rural , 2006,
Abstract: Este trabalho teve como objetivo estudar a biologia de Trichogramma em laboratório, visando a sua utiliza o em programas de manejo integrado para o controle de Bonagota cranaodes na cultura da macieira. A biologia de Trichogramma bruni Nagaraja e de duas linhagens (L3 e L4) de Trichogramma pretiosum foi realizada sobre ovos de B. cranaodes. Além disso, suas exigências térmicas e o número anual de gera es também foram determinados. A linhagem L3 apresentou maior parasitismo (52,3%), no entanto, a viabilidade foi semelhante entre as linhagens estudadas, com ciclo evolutivo de 8,7 dias, longevidade de fêmeas de 10,65 dias, temperatura base de 11,35degreesC e constante térmica de 128,70GD. O número de gera es anuais dessa linhagem em laboratório foi de 47,22 e de 13,59 gera es para as condi es da regi o de Vacaria - RS. O baixo parasitismo de T. bruni e da linhagem L4 de T. pretiosum pode estar ligado à camada de secre o existente sobre as posturas da praga. Embora este parasitismo seja considerado baixo, a utiliza o destas linhagens n o pode ser descartada dentro do sistema de Produ o Integrada da Ma , devendo novos estudos serem realizados em condi es de campo.
Altera??es ultraestruturais em larvas de Aedes aegypti submetidas ao diterpeno labdano, isolado de Copaifera reticulata (Leguminosae), e à uma fra??o rica em taninos de Magonia pubescens (Sapindaceae)
Valotto, Cleyde Ferreira Barreto;Silva, Heloisa Helena Garcia da;Cavasin, Gláucia;Geris, Regina;Rodrigues Filho, Edson;Silva, Ionizete Garcia da;
Revista da Sociedade Brasileira de Medicina Tropical , 2011, DOI: 10.1590/S0037-86822011005000010
Abstract: introduction: dengue is an important public health problem in many countries and its main vector aedes aegypti, is the mosquito most adapted to urban areas. for the first time, the mechanism of action of labdane diterpenoid extracted from copaifera reticulata and the fraction enriched of catechin tannins extracted from magonia pubescens is demonstrated through ultrastructural alterations of aedes aegypti larvae. methods: experiments were performed using a 0.9ppm solution of diterpenoid and 3.7ppm of the fraction as the main catechin tannin of molecular mass 846da. the compounds were obtained by thin layer chromatography and identified by nuclear magnetic resonance of hydrogen and mass spectrometry. larvae that achieved lethargic state were collected and dissected. next, they were contrasted with 1% uranyl acetate, dehydrated, embedded and polymerized. ultrathin sections were made, mixed with 3% uranyl acetate and lead citrate and placed in an electron microscope. results: the main ultrastructural alterations caused by the diterpenoid and by tanins in larvae of aedes aegypti were: cytoplasmic vacuolation, alteration of microvilli, cellular aging, cell disruption and degeneration, formation of secretion vesicles and structural changes in microvilli, irregular nuclei and displacement of cells in the basal lamina. conclusions: the fraction containing tannins and the diterpenoid caused the death of aedes aegypti larvae by cell destruction in the midgut.
Diterpenos de Copaifera reticulata Ducke com atividade larvicida contra Aedes aegypti (L.) (Diptera, Culicidae)
Geris, Regina;Silva, Ionizete Garcia da;Silva, Heloísa Helena Garcia da;Barison, Andersson;Rodrigues-Filho, Edson;Ferreira, Ant?nio Gilberto;
Revista do Instituto de Medicina Tropical de S?o Paulo , 2008, DOI: 10.1590/S0036-46652008000100006
Abstract: the objective of this study was to evaluate the larvicidal activity of diterpenoids obtained from the oil-resin of copaifera reticulata against aedes aegypti larvae, the principal vector of dengue and urban yellow fever. four diterpenes were obtained from oil-resin extraction with organic solvents and subsequent chromatographic and spectroscopic procedures allowed to isolation and identification of these compounds as 3-b-acetoxylabdan-8(17)-13-dien-15-oic acid (1), alepterolic acid (2), 3-b-hidroxylabdan-8(17)-en-15-oic acid (3), and ent-agatic acid (4). each compound was previously dissolved in dimethylsulphoxide, and distilled water was added to obtain the desired concentrations. twenty larvae of third instars were placed into plastic beckers, containing the solution test (25 ml), in a five repetitions scheme, and their mortality, indicated by torpor and darkening of the cephalic capsule, was recorded after 48h. probit analyses were used to determine lethal concentrations (lc50 and lc90) and their respective 95% confidence intervals. this study showed that only diterpenoids 1 and 2 exhibited larvicidal properties with lc50 of 0.8 ppm and 87.3 ppm, respectively, revealing the former as the most toxic compound against third instars of ae. aegypti. therefore, this compound seems to be an interesting source for new metabolite to be exploited.
Atividade larvicida de taninos isolados de Magonia pubescens St. Hil. (Sapindaceae) sobre Aedes aegypti (Diptera, Culicidae)
Silva, Heloísa Helena Garcia da;Silva, Ionizete Garcia da;Santos, Regina Maria Geris dos;Rodrigues Filho, Edson;Elias, Carmeci Natalina;
Revista da Sociedade Brasileira de Medicina Tropical , 2004, DOI: 10.1590/S0037-86822004000500005
Abstract: phytochemical study of the larvicidal fractions wich were carried out for the first time, isolated of the magonia pubescens, monitored by the study of efficacy against the 3rd larval instar of aedes aegypti, in the search of alternatives for the control of that mosquito and to obtain structures susceptible to chemical improving of the activity for the synthetic via of other deriveds. the fractions with biological activity were monitored chemically through chromatography of thin layer, using as revealing a solution acid of vanillin, analyzed by nuclear magnetic resonance of hydrogen and spectrometry of masses. the bioassays with the fractions were accomplished wit five replications, controlled at the temperature of 28±1oc, 80±5% of relative humidity and 12 h light. the found lethal concentrations of the fraction that it presented the largest potential larvicidal, mp-9, lc50 and lc90, were of 3,1 and 36,6ppm, respectively. all the experiments were accompanied by a control series, containing the same number of larvae.
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