973 resultados para Extração de características
Resumo:
Currently, the oil industry is the biggest cause of environmental pollution. The objective was to reduce the concentration of copper and chromium in the water produced by the oil industry. It was used as adsorbent natural sisal fiber Agave sp treated with nitric acid and sodium hydroxide. All vegetable fibers have physical and morphological properties that enablies the adsorption of pollutants. The basic composition of sisal is cellulose, hemicellulose and lignin. The features are typically found in the characterization of vegetable fibers, except the surface area that was practically zero. In the first stage of adsorption, it was evaluated the effect of temperature and time skeeking to optimize the execution of the factorial design. The results showed that the most feasible fiber was the one treated with acid in five hours (30°C). The second phase was a factorial design, using acid and five hours, this time was it determined in the first phase. The tests were conducted following the experimental design and the results were analyzed by statistical methods in order to optimize the main parameters that influence the process: pH, concentration (mol / L) and fiber mass/ metal solution volume. The volume / mass ratio factor showed significant interference in the adsorption process of chromium and copper. The results obtained after optimization showed that the highest percentages of extraction (98%) were obtained on the following operating conditions: pH: 5-6, Concentration: 100 ppm and mass/ volume: 1 gram of fiber/50mL solution. The results showed that the adsorption process was efficient to remove chromium and copper using sisal fibers, however, requiring further studies to optimize the process.
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The produced water is a byproduct formed due to production of petroleum and carries with it a high amount of contaminants such as oil particles in suspension, organic compounds and metals. Thus, these latter pollutants are very difficult to treat because of its high solubility in water. The objective of this work is to use and evaluate a microemulsioned system to remove metals ( K , Mg , Ba , Ca , Cr , Mn , Li , Fe ) of synthetic produced water. For the extraction of metals, it was used a pseudoternary diagram containing the following phases: synthetic produced water as the aqueous phase (AP), hexane as organic phase (OP), and a cosurfactant/surfactant ratio equal to four (C/S = 4) as the third phase, where the OCS (saponified coconut oil) was used as surfactant and n-butanol as cosurfactant. The synthetic produced water was prepared in a bench scale and the region of interest in the diagram for the removal of metals was determined by experimental design called. Ten points located in the phase Winsor II were selected in an area with a large amount of water and small amounts of reagents. The samples were analyzed in atomic absorption spectrometer, and the results were evaluated through a statistical assesment, allowing the efficiency analysis of the effects and their interactions. The results showed percentages of extraction above 90% for the metals manganese, iron, chromium, calcium, barium and magnesium, and around 45% for metals lithium and potassium. The optimal point for the simultaneous removal of metals was calculated using statistical artifact multiple response function (MR). This calculation showed that the point of greatest extraction of metals occurs was the J point, with the composition [72% AP, 9% OP, 19% C/S], obtaining a global extraction percentage about 80%. Considering the aspects analyzed, the microemulsioned system has shown itself to be an effective alternative in the extraction of metals on synthetic produced water remediation
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Nowadays, most of the hydrocarbon reserves in the world are in the form of heavy oil, ultra - heavy or bitumen. For the extraction and production of this resource is required to implement new technologies. One of the promising processes for the recovery of this oil is the Expanding Solvent Steam Assisted Gravity Drainage (ES-SAGD) which uses two parallel horizontal wells, where the injection well is situated vertically above the production well. The completion of the process occurs upon injection of a hydrocarbon additive at low concentration in conjunction with steam. The steam adds heat to reduce the viscosity of the oil and solvent aids in reducing the interfacial tension between oil/ solvent. The main force acting in this process is the gravitational and the heat transfer takes place by conduction, convection and latent heat of steam. In this study was used the discretized wellbore model, where the well is discretized in the same way that the reservoir and each section of the well treated as a block of grid, with interblock connection with the reservoir. This study aims to analyze the influence of the pressure drop and heat along the injection well in the ES-SAGD process. The model used for the study is a homogeneous reservoir, semi synthetic with characteristics of the Brazilian Northeast and numerical simulations were performed using the STARS thermal simulator from CMG (Computer Modelling Group). The operational parameters analyzed were: percentage of solvent injected, the flow of steam injection, vertical distance between the wells and steam quality. All of them were significant in oil recovery factor positively influencing this. The results showed that, for all cases analyzed, the model considers the pressure drop has cumulative production of oil below its respective model that disregards such loss. This difference is more pronounced the lower the value of the flow of steam injection
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Sexually transmitted diseases (STDs) are among the largest public health problems, especially in developing countries. The acquisition of these infections during early sexual activity is common and many infections have a benign course. However, in some pathogens remain in the state of latency can be reactivated and cause productive infection that may progress to severe forms. In addition, some of them are transmitted vertically resulting in congenital infection, causing immediate damage or long-term child. The classic risk factors for sexually transmitted agents are: early onset of sexual and reproductive health, multiple sexual partners throughout life, use of oral contraceptives and co-infections with different pathogens. We present the results of a cross-sectional study aimed to estimate the prevalence of genital infection by human papillomavirus (HPV), Herpes simplex virus (HSV) and Chlamydia trachomatis (CT) in a segment of the female population of the metropolitan area Christmas, among those who enrolled voluntarily sought, Basic Health Units for the examination of cancer screening cervix in the period 2008 to 2010. All participants, a total of 261 women answered a standard questionnaire by which identified the socio-demographic characteristics, classical risk factors for STDs, reproductive and sexual activity and smoking. Of each patient were obtained two samples, one for the completion of the Pap test for detection of cellular changes and the other processed for DNA extraction and analyzed by PCR (polymerase chain reaction) to detect the three pathogens studied. The population of the study was composed of sexually active women aged between 13 and 79 years, mean 38.7 years, most of them being married, low education levels and low incomes. The majority (87%) had normal results on cytology and only 2.7% had low-grade cytological abnormalities. Prevalence rates were 37.9% for HPV, 4.6% for CT and 26% for HSV. HPV prevalence was higher in women under 25, unmarried and in those who had multiple sexual partners. Women with simultaneous infection by HSV-1 and 2 had higher prevalence of HPV infection. The prevalence of HSV infection showed no association whatsoever with the risk factors analyzed and HSV-1 was the predominant type among the cases of genital HSV infection. The overall prevalence of C. Trachomatis was relatively low, thus providing greater value in younger women aged less than or equal to 20 years
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This study assessed the level of knowledge, attitude and practice of Pap smear and human papillomavirus (HPV), in addition to analyzing the prevalence of genital HPV infection, Herpes Simplex Type 2 (HSV-2) and Chlamydia trachomatis in teenagers. The study consisted of two approaches, one based only on interviews conducted with adolescents enrolled in public schools or in public health facilities in the city of Natal. The other approach involved only a group of 132 adolescents enrolled among those admitted to two health units in Natal-RN. This second group of participants two specimens were collected for laboratory analysis: one was directed to prepare the blade for the Pap test, and other processed for DNA extraction for molecular analysis, focusing on the detection of HPV, HSV-2 and C . trachomatis. The presence of DNA of the three pathogens was investigated by the technique of polymerase chain reaction (PCR). The presence of each of the three pathogens was analyzed in terms of socio-demographic characteristics, as well as sexual and reproductive activity to identify risk factors for infection and development of lesions of the uterine cervix. The results show that the adolescents in this study had levels of knowledge and attitude very low, both in relation to cytology to HPV as though they have made a reasonable percentage of adequate practice exam and prevention of HPV infection. The overall prevalence of HPV infection was 54.5% and 48.2% in adolescents with normal cytology and 86.4% in those with abnormal cytology. We observed a higher proportion of cases of infection in the age group of 18 to 21. The prevalence of HPV infection was slightly higher among pregnant teenagers. The overall prevalence of HSV-2 infection was 13.6% and 11.8% in women with normal cytology and 22.7% in those with abnormal cytology. A higher proportion of cases of infection was found in the age group from 14 to 17, with a slightly higher prevalence among pregnant women. The C. trachomatis was found with an overall prevalence of 19.7% and 21.8% in adolescents with normal cytology and 9.1% in those with abnormal cytology. The prevailing rate was highest in the age group 18 to 21 years and in nonpregnant
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Herpes simplex is a virus that can be transmitted sexually and is potentially associated with vertical transmission. This study evaluated the prevalence of genital infection by herpes simplex virus (HSV) types 1 and 2 in pregnant and nonpregnant care in the city of Natal / RN, including a total of 222 women, 92 pregnant and 130 nonpregnant. The participants answered a questionnaire to obtain data and socio-demographic characteristics, as well as potential risk factors for sexually transmitted diseases. After the interview, we collected two cervical specimens, one for the Pap test and the other for DNA extraction and analyzed by polymerase chain reaction (PCR) to detect both virus serotypes. Then the women underwent a clinical examination by colposcopy. For statistical analysis, we used the chi-square and logistic regression by SSPS 17.0 Statistic. Most women were up to 30 years of age, nonwhite ethnicity, married, elementary education, family income below the poverty level; initiated sexual activity with age up to 18 years; had more than one sexual partner lifelong and was not pregnant, but has had at least one child. The HSV-1 showed a prevalence of 26.1% among pregnant women and 30.0% in non-pregnant women. While HSV-2 prevalence was found with 10.9% and 19.2% in pregnant and nonpregnant women, respectively. The largest proportion of morphological changes of the uterine cervix was detected among nonpregnant women, both in cytology and in colposcopy. The women were nonwhite ethnicity, married, became pregnant aged less than or equal to 18 years and who had one to two pregnancies had a lower risk of acquiring genital HSV infection. There was a high prevalence of genital HSV infection, HSV-1 is more prevalent than HSV-2. No association was found between morphological changes of the uterine cervix and the presence of the virus in pregnant and nonpregnant women, nor between genital HSV infection and the classic risk factors for sexually transmitted diseases
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Objetivou-se estudar as características quantitativas da carcaça de 36 bubalinos (12 Murrah 12 Jafarabadi e 12 Mediterrâneo), com idade média de 18 meses e peso vivo inicial de 330 kg, terminados em confinamento. Os 12 animais de cada grupo genético foram divididos aleatoriamente em três subgrupos de quatro animais e submetidos aos seguintes tratamentos: Maturidade 1: 400 kg PV ao abate; Maturidade 2: 450 kg PV ao abate; Maturidade 3: 500 kg PV ao abate. Durante o experimento, uma ração única, em que 50% da MS foi composta por volumoso, foi fornecida, ad libitum, para todos os animais. Após os abates pré-fixados, determinou-se o peso corporal vazio (PCVZ) dos animais pelo somatório das partes integrantes do corpo. Não houve diferença entre grupos genéticos e maturidades, em relação à porcentagem dos cortes dianteiro, paleta, traseiro total e alcatra completa. O rendimento de traseiro especial foi maior nos animais abatidos aos 400 kg PV e menor naqueles com 500 kg PV, enquanto o dos animais com 450 kg PV não diferiu dos demais. O rendimento de ponta-de-agulha, por sua vez, foi maior nos animais com 500 kg PV e menor nos com 400 kg PV. Os valores observados nesses dois pesos de abate não diferiram do obtido nos animais com 450 kg. A produção de carne a partir das raças Murrah, Jafarabadi e Mediterrâneo criadas no Brasil não difere quanto aos rendimentos de carcaça, traseiro, dianteiro e dos principais cortes básicos de interesse comercial.
Resumo:
Objetivou-se avaliar as características físicas, químicas e sensoriais da carne de búfalos abatidos em diferentes períodos de confinamento. Foram utilizados 20 bubalinos da raça Murrah, castrados, descornados, com idade média inicial de 15 meses, abatidos aos 75, 100, 125 ou 150 dias de confinamento. Após o abate, as carcaças foram identificadas e resfriadas por 24 horas. Durante a desossa, foram colhidas amostras do contrafilé entre a 10ª e 11ª costelas para análise das características sensoriais e das perdas por cocção; entre a 11ª e 12ª costelas para avaliação da composição centesimal, do valor calórico, do pH e do índice de fragmentação miofibrilar (IFM); e entre a 12ª e 13ª costelas para a avaliação do escore de marmorização e da força de cisalhamento. A composição centesimal, o pH, a força de cisalhamento, o valor calórico, as perdas por cocção e o IFM não diferiram estatisticamente entre os períodos de confinamento. O grau de marmorização diferiu entre as idades de abate, uma vez os animais abatidos aos 75 dias de confinamento apresentaram escore de 1,25; os abatidos aos 100 e 125 dias, escore 2; e aqueles abatidos aos 150 dias de confinamento, escore 2,2. em todos os períodos de confinamento, a carne bubalina foi classificada como macia (média 3,94 kgf) e apresentou com características que não diferiram pelo painel sensorial entre os 75 e 150 dias de confinamento. O abate de bubalinos aos 75 e 150 dias de confinamento não influencia as características sensoriais sabor, aroma e cor da carne bubalina.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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O Eucalyptus grandis é uma das espécies mais cultivadas no Brasil devido à sua produtividade e qualidade da madeira. Avaliaram-se o efeito da aplicação de lodo de esgoto tratado (0 a 40 t ha-1 base seca) e uma dose de adubo mineral nos atributos físicos e químicos da madeira de Eucalyptus grandis de árvores com cinco anos de idade, no Município de Itatinga, São Paulo, Brasil. O tipo de solo foi caracterizado como Latossolo Vermelho-Amarelo Distrófico (argila = 120 g kg-1 na camada de 0-20 cm) e o clima, como mesotérmico úmido (Cwa), segundo a classificação de Köeppen. O delineamento experimental foi o de blocos ao acaso, com seis tratamentos e quatro repetições. O diâmetro à altura do peito (DAP), a altura das árvores e o volume de madeira foram obtidos em todas as parcelas de oito árvores com DAP na classe de maior freqüência. As caracterizações físicas e químicas da madeira foram realizadas de acordo com as normas da ABTCP, TAPPI e ABNT. O lodo de esgoto diminuiu a densidade básica da madeira, mas não afetou os teores de celulose, lignina, extrativos e o poder calorífico da madeira. O decréscimo de densidade da madeira pela adubação com lodo de esgoto foi compensado pela maior produtividade de madeira.
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Dentistry, as a science and field of knowledge, has presented a substantial development in the last decades in the areas of research and education. The aim of this study was to evaluate the Brazilian scientific production in Dentistry, as from their methodological outlining, which characterizes the XXI Century. Five thousand two hundred and three study abstracts were evaluated, comprising works presented in the meetings of the Brazilian Society of Dentistry Research (SBPqO), during the period of 2001 to 2006. The main results identify that, as for the methodology used in the researches, there was a predominance of the studies of an individuate, interventionist and longitudinal nature; of the researches in the areas of Dentistry, Periodontology, Endodontics, Pedodontics and Collective Oral Health and experimental studies about clinical researches or with collective subjects. The inter and multidisciplinarity are pointed out in the outlining of this study, as the triad Education-Health-Research is discussed, so that they transcend in their fields of action, in the direction of the transdisciplinarity. It is concluded that, in the studied period, there was a reasonable and balanced production in Brazilian dental field
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Hyperhidrosis is an idiopathic condition characterized by excessive sweating. Symptoms generally begin in childhood or early adolescence, and rarely improve with age. The excessive localized sweating generally occurs either spontaneously, or in association with stressful or emotionally charged situations. This prospective study aimed to investigate predictive factors for compensatory hyperhidrosis after thoracoscopic sympathicotomy. From 2000 to 2002, 80 patients (53 female and 27 male) underwent hyperhidrosis surgery. The patients, ranging from 12 to 56 years old, were studied and followed-up for 42.51 ±5.98 months. A satisfaction grading using a visual analogue scale -VAS (0 = not at all satisfied, and 10 = fully satisfied) was used. The surgical procedure was performed bilaterally on the second ganglion (T2) for facial hyperhidrosis, on the third and fourth ganglia (T3 and T4) for axillary hyperhidrosis, and on the third ganglion (T3) for palmar hyperhidrosis. The results showed that, 68 patients (85%) presented with compensatory sweating (CS), which was classified as mild (33.8%), moderate (33.8%) and severe (32.4%). Considering the final surgical results, 70 patients (87.5%) were satisfied with the outcome of the operation, while 10 patients (12.5%) were dissatisfied. Degrees of satisfaction varied according to sex, age, BMI and extent of denervation. Moreover, the compensatory hyperhidrosis was more severe in abdomen and back than in legs. In conclusion, although CS is a frequent adverse effect of sympathicotomy, the degree of patient satisfaction was high. Some factors were related to the occurrence and severity of CS and the most adequate patients to be submitted to this operation are young adult women whose BMI is less than 24.9
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Estudou-se a influência das quatro estações do ano nas características do sêmen e nas concentrações de testosterona e cortisol em touros. Cinco touros Nelore e cinco Simental entre 48 e 72 meses de idade, criados extensivamente, foram avaliados andrologicamente por meio de exames físicos das características morfológicas do sêmen e das concentrações séricas de testosterona e cortisol. Houve redução na motilidade e no vigor do sêmen no inverno (P<0,05) na raça Simental. Observou-se correlação (P<0,01) entre testosterona x motilidade (0,69) e testosterona x vigor (0,57) na raça Simental, e cortisol x motilidade (0,68) e cortisol x vigor (0,65) na raça Nelore. O efeito das estações do ano modificou a qualidade do sêmen com aumento da motilidade e vigor espermáticos na primavera e verão nos touros Simental. A concentração de cortisol diminuiu no outono nos touros Nelore.
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Cordeiros criados em regime de pasto, provenientes de ovelhas Romney acasaladas com três raças paternas (Romney, East Friesian x (Finn x Texel) e Finn x Poll Dorset), foram avaliados quanto às características de qualidade da carne. Os cordeiros foram abatidos aos 150 e 300 dias de idade, cada lote com 15 animais de cada raça paterna, totalizando 90 animais. A carne dos cordeiros Romney foi mais macia que a dos demais genótipos. O pH final do músculo Semimembranosus dos cordeiros abatidos mais precocemente foi superior (5,61) ao dos abatidos mais tardiamente (5,58), entretanto estes últimos apresentaram carne com menor maciez (11,16 kg) que os abatidos aos 150 dias de idade (7,45 kg). Com relação à cor, a luminosidade da carne de cordeiros abatidos aos 150 dias foi maior (38,20) que a dos abatidos mais tardiamente (36,80), mas não foi afetada pelo genótipo. Concluiu-se que o genótipo e a idade de abate influíram na produção e qualidade da carne ovina.
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Existem fortes evidências de que os programas de rastreamento baseados em citologia resultaram em diminuição significativa da incidência e mortalidade por câncer do colo do útero, no entanto, um excesso substancial de tratamento de lesões intraepiteliais de baixo grau que dificilmente progrediriam para carcinoma cervical resulta da baixa especificidade do tradicional rastreio citológico. A detecção precoce das lesões através do rastreamento citológico e a avaliação do grau histológico em espécimes cervicais são fundamentais, entretanto não permitem identificar quais pacientes terão maior probabilidade de progressão para lesões de alto grau e carcinoma invasivo. A busca de potenciais marcadores de prognóstico; objetivando o entendimento da progressão das lesões intraepiteliais é de suma importância. Acredita-se que fatores imunoregulatórios, imunogenéticos e proteínas do ciclo celular estejam intimamente envolvidos no processo de carcinogênese. Considerando o exposto, a proposta do projeto foi inicialmente avaliar a eficácia da citologia oncológica no rastreamento do câncer cervical, foi investigado ainda o polimorfismo do gene do fator de transcrição FOXP3 e a expressão da proteína do ciclo celular P63 (P63) associados respectivamente a diagnóstico e prognóstico das lesões cervicais. Em um primeiro momento foi realizado estudo transversal que envolveu 3194 mulheres. As participantes foram submetidas à citologia e biópsia de colo dirigida por colposcopia e os resultados foram comparados para verificar-se a acurácia do teste de Papanicolaou na detecção de lesões intraepiteliais e câncer cervical. Posteriormente, realizou-se estudo comparativo do tipo observacional estratificado em três grupos: Grupo 1: 16 casos com diagnóstico histopatológico de metaplasia/cervicite, considerados normais, Grupo 2: 11 casos com lesão de baixo grau (LSIL) e Grupo 3: 15 casos com lesão de alto grau (HSIL) ou carcinoma epidermoide de colo. Um total de 42 participantes respondeu a um questionário epidemiológico padronizado sobre as características demográficas, hábitos pregressos, história reprodutiva e de comportamento sexual. Após exame colposcópico, foram coletados fragmentos de espécimes cervicais para a pesquisa da expressão proteica da P63 por imunohistoquímica. Amostras de sangue periférico foram coletadas para extração do DNA e detecção do polimorfismo do gene FOXP3. No primeiro estudo em que se avaliou a acurácia do teste de Papanicolaou, encontrou-se sensibilidade de 0,83, valor preditivo positivo (VPP) de 0,77 e especificidade de 0,23 no rastreamento das lesões cervicais e câncer de colo. viii Melhores resultados foram observados quando se avaliou a acurácia diagnóstica para lesões de alto grau e carcinoma com VPP de 0,99 e especificidade de 0,84.No estudo subsequente onde se comparou a expressão da proteína P63 observou-se maior número de núcleos marcados no grupo com lesões intraepiteliais de alto grau e câncer quando comparado ao grupo com biópsias negativas (p=0,0004). No último estudo pesquisou-se a associação do polimorfismo do gene FOXP3 com lesões intraepiteliais cervicais sendo evidenciada maior prevalência do genótipo heterozigoto, CT, no grupo com lesões de colo na histopatologia (p=0,027). Mulheres com lesões intraepiteliais de baixo ou alto grau e câncer de colo de útero apresentam maior expressão da proteína P63 e maior prevalência de genótipo heterozigoto do gene FOXP3 em comparação com as sem lesões cervicais. A associação da pesquisa da expressão da proteína e do polimorfismo do gene pode tornar os exames utilizados atualmente para a avaliação diagnóstica e prognóstica das lesões de colo uterino mais efetivos em detectar quais as mulheres com maior risco para progressão para câncer