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2005-06-01
Resumo em português Este trabalho objetivou verificar a concentração do mercado internacional de madeira serrada, por meio dos índices de concentração e desigualdade de mercado e das estruturas de classificações de mercado. Utilizou-se como indicador a exportação de 154 diferentes nações nos anos de 1997 e 1999, sendo constatadas a alta concentração e desigualdade do mercado internacional de madeira serrada e a evolução desses parâmetros no período analisado. Resumo em inglês The objective of this study was to analyze the concentration of the international market of sawn wood. Concentration and market inequality indexes and structures of market classifications were used. The base of information was the exportation of 154 different nations in 1997 and 1999. A high concentration and inequality of the sawn wood international market and the evolution of these parameters in the analyzed period, was found.
2009-12-01
Resumo em português O objetivo deste trabalho foi avaliar se a poluição por fluoreto observada em 1996 em Cubatão (SP), utilizando a vegetação como biomarcador, teve alterações nos últimos dez anos. Folhas de Terminalia cattappa (chapéu do sol), localizadas na região das indústrias de fertilizantes e na área urbana municipal, foram coletadas em 1996 e 2006. As folhas foram desidratadas, pulverizadas e fluoreto extraído com água foi analisado com eletrodo específico. A concentr (mais) ação de fluoreto encontrada nas folhas das árvores localizadas ao redor do pólo de fertilizantes foi doze vezes maior do que a naquelas da área urbana, tanto em 1996 como 2006. Sugere-se que a poluição ambiental por fluoreto em Cubatão não apresentou melhoria em dez anos. Resumo em inglês The aim of this study was to evaluate if fluoride pollution found in 1996 in Cubatão, SP, Brazil, using the vegetation as biomarker, changed in the last ten years. Leaves of Terminalia cattappa located at the industrial area around the industries of fertilizers and in the urban area of the city were collected in 1996 and 2006. They were dried, powdered and fluoride water soluble extracted was analyzes with specific electrode. The fluoride concentration in the leaves arou (mais) nd fertilizer industries was 12 times greater than that found in the urban area, either in 1996 or 2006, respectively. The data suggest that in the last ten years the environmental pollution by fluoride in Cubatão has not improved.
2009-12-01
Resumo em português O objetivo deste trabalho foi avaliar se a poluição por fluoreto observada em 1996 em Cubatão (SP), utilizando a vegetação como biomarcador, teve alterações nos últimos dez anos. Folhas de Terminalia cattappa (chapéu do sol), localizadas na região das indústrias de fertilizantes e na área urbana municipal, foram coletadas em 1996 e 2006. As folhas foram desidratadas, pulverizadas e fluoreto extraído com água foi analisado com eletrodo específico. A concentr (mais) ação de fluoreto encontrada nas folhas das árvores localizadas ao redor do pólo de fertilizantes foi doze vezes maior do que a naquelas da área urbana, tanto em 1996 como 2006. Sugere-se que a poluição ambiental por fluoreto em Cubatão não apresentou melhoria em dez anos. Resumo em inglês The aim of this study was to evaluate if fluoride pollution found in 1996 in Cubatão, SP, Brazil, using the vegetation as biomarker, changed in the last ten years. Leaves of Terminalia cattappa located at the industrial area around the industries of fertilizers and in the urban area of the city were collected in 1996 and 2006. They were dried, powdered and fluoride water soluble extracted was analyzes with specific electrode. The fluoride concentration in the leaves arou (mais) nd fertilizer industries was 12 times greater than that found in the urban area, either in 1996 or 2006, respectively. The data suggest that in the last ten years the environmental pollution by fluoride in Cubatão has not improved.
2007-03-01
Resumo em português OBJETIVOS: Comparar a concentração total de proteínas no humor aquoso entre pacientes com glaucoma primário de ângulo aberto e sem glaucoma. MÉTODOS: Foram coletadas amostras de humor aquoso de 22 pacientes com glaucoma primário de ângulo aberto (grupo GPAA) no momento da trabeculectomia. Na coleta, 0,1 mL de humor aquoso foi aspirado da câmara anterior através de uma agulha de calibre 26, no início do procedimento cirúrgico. Coleta semelhante foi realizada em (mais) 22 pacientes sem glaucoma no início da cirurgia de catarata (grupo controle). A amostra de humor aquoso foi armazenada a -20°C após a coleta. A concentração total de proteínas no humor aquoso foi determinada por meio de um teste colorimétrico. RESULTADOS: A média geométrica da concentração total de proteínas no humor aquoso foi de 32 mg/dL (amplitude: 8-137 mg/dL) no grupo glaucoma primário de ângulo aberto e de 16 mg/dL (amplitude: 2-85 mg/dL) no grupo controle. A razão da concentração total de proteínas no humor aquoso entre estes dois grupos foi de 2,0 (intervalo de confiança de 95%: 1,3 a 3,2; p=0,003). CONCLUSÕES: A concentração total de proteínas no humor aquoso de pacientes com glaucoma primário de ângulo aberto foi aproximadamente duas vezes maior quando comparada aos pacientes sem glaucoma. Resumo em inglês PURPOSE: To compare total protein concentration in the aqueous humor of primary open-angle glaucoma and non-glaucomatous patients. METHODS: Aqueous humor samples were obtained from 22 patients just before trabeculectomy for clinically uncontrolled primary open angle glaucoma (POAG group). Aqueous humor (0.1 mL) was aspirated by inserting a 26-gauge needle into the anterior chamber. The same procedure was performed in 22 non-glaucomatous patients just before cataract surge (mais) ry (control group). Immediately after collection, the aqueous humor was stored at -20°C. Aqueous humor total protein concentration was determined using a colorimetric assay. RESULTS: The geometric mean of total protein concentration of the aqueous humor samples was 32 mg/dL (range: 8-137 mg/dL) in the primary open angle glaucoma group and 16 mg/dL (range: 2-85 mg/dL) in the control group. The ratio of the protein concentration between the two groups was 2.0 (95% confidence interval: 1.3 to 3.2; p=0.003). CONCLUSIONS: The total protein concentration in primary open-angle glaucoma aqueous humor was approximately two times higher than that in non-glaucomatous subjects.
2003-09-01
Resumo em português Este trabalho avaliou a influência da concentração de amido de milho nas características físicas e na liberação in vitro de paracetamol a partir de comprimidos. Os granulados foram analisados quanto à granulometria e densidades aparentes bruta e compactada e os comprimidos quanto ao peso médio, espessura, dureza, friabilidade, tempo de desintegração. Os comprimidos foram preparados a partir de granulados obtidos por granulação a úmido, utilizando cozimento d (mais) e amido a 10% como agente granulante, segundo três formulações. Embora os comprimidos obtidos tenham apresentado características dentro dos limites farmacopéicos, os resultados indicam que variações da concentração de amido provocam diferenças nos diversos parâmetros físicos estudados. Concentração mais alta de amido em pó dá origem, provavelmente, à interação entre os componentes da fórmula, interferindo na liberação in vitro do fármaco. Isto demonstra a importância de se otimizar a concentração dos adjuvantes numa formulação de comprimidos, pois, embora uma pequena variação nesta concentração não exerça efeito significativo no tempo de desintegração, a quantidade de fármaco liberado pode ser substancialmente alterada. Resumo em inglês This paper describes the influence of maize starch concentration on the physical characteristics and on in vitro release of acetaminophen from compressed tablets. The granulates were analyzed in relation to size distribution and bulk and compacted densities, and the tablets in relation to mean weight, thickness, hardness, friability and disintegration time. The tablets were prepared from granulates made by wet granulation with 10% starch paste in three formulations. Altho (mais) ugh the tablets obtained have presented characteristics in accordance with pharmacopeial limits, the results indicate that variations on starch concentration cause differences on the several physical parameters studied. Higher starch concentration probably originates an interaction among the ingredients of the formulations, interfering on the in vitro drug release.This fact demonstrates the importance in optimizing the concentration of the adjutants in a tablet formulation, because, although a short variation in this concentration has no significant effect on disintegration time, the amount of released drug can be substantially modified.
2010-12-01
Resumo em português O objetivo desse trabalho é estudar a mudança na concentração dos mercados da indústria brasileira de mineração e transformação entre 1996 e 2003, realizando uma decomposição do índice de Herfindahl-Hirschman em variação da distribuição do tamanho e do número de empresas. Os resultados obtidos sugerem que, na média, a indústria sofreu reduzida mudança no período; contudo, apontam que, em um grupo de indústrias, as mudanças no nível de concentraçã (mais) o foram substanciais. Indicam também que a maior responsabilidade por essas mudanças está associada a alterações na desigualdade do tamanho, apesar de o período ter presenciado um forte movimento de entrada de novas empresas em diversos segmentos industriais. Resumo em inglês The aim of this paper is to study the changes in market concentration in the Brazilian mining and manufacturing industries that took place from 1996 to 2003. The paper decomposes the Herfindahl-Hirschman index into variations in the size distribution and the number of firms. The results show that the average concentration did not change greatly in the period analyzed; however, a small group of industries showed significant differences in concentration. In these cases, changes in size distribution appear to have more importance than changes in the number of firms.
2002-05-01
Resumo em inglês The reaction between hydroxy-terminated polybutadiene and isophorone diisocyanate constitutes the base of the curing process of the most composite solid propellant used in the propulsion of solid rocket propellant. In this work, differential scanning calorimetry and viscosity measurements were used to evaluate the effect of the ferric acetylacetonate catalyst concentration on the reaction between HTBR and IPDI. These analyses show one exotherm, which shifts to lower tempe (mais) ratures as the catalyst concentration increases. The viscosity analyses show that the increase of temperature causes, at first, a reduction in the mixture viscosity, reaching a minimum range called gelification region (increasing the crosslinking density).
2008-01-01
Resumo em inglês Deficiency of micronutrients is a public health problem. Cow milk is a source of retinol. The objective of this study is to evaluate the retinol concentration in milk commercialized in Natal/RN. Ten samples were taken of each brand of UHT milk. Vitamin content was determined by HPLC using the Shimadzu LC-10 AD Chromatograph, coupled to the Shimadzu SPD 10 A UV-VIS Detector and the Shimadzu C-R6A Chromatopac Integrator with Shim-pack CLC-ODS (M) column, measuring 4.6 mm x (mais) 25 cm. The mobile phase was 100% methanol, with a flow of 1 mL/min. The mean retinol concentration varied between 22.7 ± 4.9 µg/100 mL and 44.1 ± 4.1 µg/100 mL, with the differences statistically significant (p
2004-10-01
Resumo em inglês The aim of this study was the determination of the critical micelle concentration (CMC) of the sodium dodecyl sulfate (SDS) surfactant using spectroscopic and conductimetric determinations and to compare these methodologies in the determination of the CMC of different humic acids (HA). The CMC obtained by conductimetric determination was satisfactory. By spectroscopic determination two values of the CMC were obtained for HA. These values can be to due the intra and intermolecular interactions in the HA structure.
2010-01-01
Resumo em inglês This work describes CE preconcentration strategies based on the effect of manipulation of the disperse/secondary velocity. Introduced by Terabe et al. in 1984, micellar electrokinetic chromatography is a powerful separation approach that increases the usage of electrokinetic phenomena for the separation of nonionic compounds. The main disadvantage of MEKC is the low concentration sensitivity associated with the limited optical path length for on-capillary photometric dete (mais) ction and the limited volume of sample solution that can be injected. This paper compiles on-line concentration strategies for neutral analytes by sample stacking and sweeping in micellar electrokinetic chromatography.
2010-12-01
Resumo em português FUNDAMENTOS: A letalidade dos carcinomas espinocelulares (CECs) de pele é considerada baixa. Os CECs de boca têm prognóstico ruim. Evidências atuais sugerem que os mastócitos, residentes no tecido normal, contribuem para a tumorigênese dos CECs, provavelmente por promoverem angiogênese. OBJETIVO: Comparar a concentração de mastócitos em CECs da pele e da boca e avaliar se há correlação com o grau de diferenciação desses tumores. MATERIAL E MÉTODOS: Foram a (mais) nalisados 30 casos de CEC de pele e 34 casos de CEC de boca. A coloração de azul de toluidina, para evidenciar os mastócitos, foi realizada nos blocos com a área central da neoplasia. RESULTADOS: Apenas um caso de CEC de pele apresentou concentração de mastócitos de 0-10 e nenhum caso de CEC de boca apresentou concentração maior que 201 mastócitos no tumor. A maioria dos CECs de boca tem concentração de mastócitos entre 0 e 10 (47% - n = 16); 80% dos CECs de pele têm concentração acima de 51 mastócitos. Todos os casos de CEC de boca com concentração entre 100 e 200 mastócitos e 80% daqueles com concentração entre 51 e 99 eram de lábio. A concentração de mastócitos não está relacionada ao grau de diferenciação do tumor. CONCLUSÃO: A concentração de mastócitos é menor nos CECs de boca, exceto nos de lábio, podendo refletir uma menor necessidade de ativação de células do microambiente para melhorar a vascularização nos cânceres de boca. Resumo em inglês BACKGROUND: The lethality of squamous cell carcinomas (SCC) of the skin is considered low. SCC in the mouth is usually associated with poor prognosis. Current evidence suggests that mast cells in the normal tissue contribute to the tumorigenesis of SCC, probably by promoting angiogenesis. OBJECTIVE: The aim of this study was to compare the concentration of mast cells in SCC of the mouth and skin and evaluate whether there is a correlation with the degree of differentiatio (mais) n of these tumors. MATERIAL AND METHODS: Thirty cases of SCC of the skin and 34 of the mouth were investigated. Toluidine blue staining was used to identify mast cells in blocks containing the central portion of the neoplasm. RESULTS: A concentration of between 0 and 10 mast cells was found in one single case of SCC of the skin and there were no cases of SCC of the mouth with concentrations of mast cells in the tumor >201. In the majority of cases of SCC of the mouth (47%; n=16), mast cell concentration was between 0 and 10, with a concentration >51 mast cells in 80% of cases of SCC of the skin. All the cases of SCC of the mouth with a concentration of mast cells between 100 and 200 and 80% of those with a concentration of 51-99 were located on the lip. The concentration of mast cells was unrelated to the degree of differentiation of the tumor. CONCLUSION: The concentration of mast cells is lower in SCC of the mouth except when the tumor is located on the lip. This may reflect a lower need for cell activation in the microenvironment to improve vascularization in oral cancer.
2007-04-01
Resumo em português Os mecanismos fisiopatológicos do refluxo laringofaríngeo (RLF) são pouco conhecidos. O Fator de Crescimento Epidérmico (EGF) é a proteína de produção salivar com maior ação na regeneração do epitélio da orofaringe e tubo digestivo alto, tendo sido demonstradas deficiências em sua concentração salivar em indivíduos com RLF. OBJETIVO: Comparar a concentração salivar de EGF em um mesmo indivíduo com RLF antes e após o tratamento. MATERIAL E MÉTODO: Nes (mais) te estudo prospectivo doze indivíduos com DRGE e RLF de moderada intensidade tiveram sua saliva espontânea coletada antes e após o tratamento e controle da doença. A concentração salivar de EGF foi estabelecida através de exame de ELISA (Quantikine ®). RESULTADOS: Onze pacientes eram do sexo feminino e um do sexo masculino, com idade média de 49 anos. A concentração salivar de EGF pré-tratamento foi de 2.867,6pg/mL e a pós-tratamento foi 1.588,5pg/mL, sendo esta diferença estatisticamente significante (p=0,015). DISCUSSÃO E CONCLUSÕES: Apesar de a concentração salivar de EGF ser maior nos indivíduos antes do tratamento, esta não consegue alcançar àquela de uma população normal (estabelecida previamente), o que sugere uma deficiência primária deste importante fator de defesa em indivíduos com RLF. Resumo em inglês The Laryngopharyngeal Reflux (LPR) physiopathology is still unknown. The Epidermal Growth Factor (EGF) is a biologically active salivary protein that aids in the rapid regeneration of the oropharyngeal and upper digestive tract mucosas. Salivary deficiency of this protein in patients with LPR has been demonstrated in previous studies. AIM: To compare salivary EGF concentration in patients with LPR before and after treatment. MATERIALS AND METHODS: In this prospective stud (mais) y twelve patients with GERD and moderate LPR were studied. Whole saliva samples were collected before and after treatment and salivary EGF concentration was determined using a commercially available ELISA kit (Quantikine ®). RESULTS: There were eleven females and one male among the patients, the mean age was 49 years. The mean pre-treatment salivary EGF concentration was 2,867.6 pg/mL and the mean post treatment EGF concentration was 1,588.5 pg/mL. This difference was statistically significant (p=0.015). DISCUSSION AND CONCLUSIONS: Although salivary EGF concentrations are higher before LPR treatment, the concentration is still much lower than the mean salivary EGF concentration in normal individuals without LPR, which suggests a primary disorder of this defense factor in individuals with LPR.
2009-04-01
Resumo em português Avaliou-se o efeito da fonte de fósforo usado como fertilizante do capim-mombaça (Panicum maximum Jacq. cv. Mombaça) sob pastejo, sobre a produção de material morto, material senescente e liteira, e sobre a concentração e a quantidade de minerais (N, P, K, Ca e Mg) no material morto. No experimento, realizado no período de dezembro/2003 a abril/2004, utilizaram-se os tratamentos: testemunha (sem aplicação de fósforo), superfosfato simples+superfosfato triplo e (mais) Yoorin, os últimos usados como fonte de fósforo. O manejo do pasto foi realizado com novilhos em pastejo contínuo e cargas variáveis. Utilizou-se o delineamento em blocos completos ao acaso, com três repetições. A produção de material morto, senescente, liteira e a percentagem de material morto não foram diferentes segundo a fonte de fósforo. A produção de material morto variou de 4.521 a 5.097kg ha-1. A concentração e a quantidade de N, K, Ca e Mg no material morto foram semelhantes entre os tratamentos, a quantidade e a concentração de P foram diferentes segundo a fonte de fósforo, variando de 2,16 a 5,04kg ha-1 e 0,52 a 1,01gk g-1, respectivamente. O uso das fontes de fósforos não afetou a produção de massa seca de liteira, material senescente, material morto e a concentração e quantidade de minerais do material morto. Resumo em inglês The effects of phosphorus sources (Yoorin, simple superphosphate (SS) + triple superphosphate (TS)) of fertilizers of Mombaçagrass (Panicum maximum Jacq. cv. Mombaça) pasture were evaluated on the death and senescent material, litter production, and concentration and amount of minerals (N, P, K, Ca, and Mg) in the pasture, under grazing. The experiment was carried out from December/2003 to April/2004. The grazing method was the continuous stocking and variable stocking (mais) rate, and the animals were crossbred. The design was a randomized complete block with three replications. The phosphorus source did not have significant effect on the death and senescent material and litter production, but the death material production ranged from 4,521 to 5,097kg ha-1. The phosphorus source did not have significant effect on the amount and concentration of N, K, Ca, and Mg. However, the phosphorus amount and concentration were different, influenced by the phosphorous source, ranging from 2,16 to 5,04kg ha-1 and 0,52 to 1,01gkg-1, respectively. The use of the phosphorus sources did not change the litter, senescent and death production, and the concentration and amount of minerals in the death material.
2008-01-01
Resumo em inglês Mild steel blankets were covered with electrolytic copper thin layer, from cyanide bath, being evaluated the influence of the carbonate concentration in the physiochemical properties of those deposits. The cell voltage decreased as the current intensity decreased, but the adherence of the deposit was not enhanced, showing that the increment of carbonate concentration causes substantial problems. Chemical solubilization reactions of air-bearing carbon dioxide and oxidation (mais) of free cyanide ions through dissolved oxygen evolved in the anodic processes contribute to the copper plating to occur in an inefficient way. The best optimal conditions require a carbonate concentration below 50 g L-1.
2009-01-01
Resumo em inglês The participation of the students in the planning, execution and discussion of experimental results is important for the valuation of the role of them in the construction of the chemical knowledge implicited in the approach between education and research. This work relates either the construction of selective membrane electrodes for surfactants and its application in the potenciometric determination of the critical micellar concentration of the sodium dodecyl sulfate (SDS (mais) ) and dodecyltrimethylammonium bromide (DTAB) surfactants. In adition it´s possible to discuss the potenciometric results in matching with the data valued for the tensiometric and condutimetric traditionally used in the physical-chemistry lessons.
2006-06-01
Resumo em inglês This is a review about the use of Blue rayon in the extraction and concentration of environmental contaminants in the aquatic environment. Blue rayon is an adsorbent composed of fibers covalently linked with copper phthalocyanine trisulphonate that has the ability to selectively adsorb polycyclic compounds. Blue rayon can be used in situ, in columns or in flasks. This method showed to be efficient in the extraction of important classes of environmental contaminants like t (mais) he polycyclic aromatic hydrocarbons (PAHs), aromatic amines and phenylbenzotriazoles (PBTAs) and can be an important tool in monitoring studies for the evaluation of water quality.
2002-10-01
Resumo em inglês The aim of this study was to estimate the correlation between scrotal girth and spermatic concentration in German Sheepherd dogs. Thirteen German Sheepherd dogs were used and 44 semen samples were obtained by digital manipulation. The ejaculate was separated in its three fractions. The sperm rich fraction was kept for evaluation and determination of spermatic concentration by spectrofotometry. The parameters were expressed as mean and standard deviation. Spearman correlat (mais) ion test was used to estimate the correlation between spermatic concentration and scrotal girth. The mean spermatic concentration was 568.45±314.91x10(6) sptz/ml and the mean scrotal girth was17.6±1.6 cm and the correlation was r = 0.10. It can be conclude that scrotal girth can not be an appropriate measurement as indicative of spermatic concentration in German Sheepherd dogs.
2008-01-01
Resumo em português Esse estudo teve como objetivo investigar a efetividade da suplementação semanal de ferro na concentração de hemoglobina, no estado nutricional e no desenvolvimento mental e motor de lactentes em quatro creches municipais do Recife, Pernambuco, Brasil. O estudo consistiu de uma intervenção do tipo antes-depois realizada com suplementação semanal com ferro por seis meses, em uma amostra de 76 crianças com idade entre 4 e 24 meses, no período de fevereiro a dezemb (mais) ro de 2005. Os desenvolvimentos mental e motor foram avaliados pela Escala de Desenvolvimento Infantil de Bayley II. Após a suplementação observou-se um aumento significante na concentração de hemoglobina, apenas no grupo de lactentes com hemoglobina inicial Resumo em inglês This study analyzed the effectiveness of weekly iron supplementation on hemoglobin concentration, nutritional status, and mental and motor development of infants at four public daycare centers in Recife, Pernambuco State, Brazil. This was a before-after intervention study conducted with weekly iron supplementation for six months in a sample of 76 infants in the 4 to 24 month age group, from February to December 2005. Mental and motor development was assessed through the B (mais) ayley Scale of Infant Development II. After supplementation, a significant increase was observed in hemoglobin concentration in the group of infants with initial hemoglobin level
2008-01-01
Resumo em português Esse estudo teve como objetivo investigar a efetividade da suplementação semanal de ferro na concentração de hemoglobina, no estado nutricional e no desenvolvimento mental e motor de lactentes em quatro creches municipais do Recife, Pernambuco, Brasil. O estudo consistiu de uma intervenção do tipo antes-depois realizada com suplementação semanal com ferro por seis meses, em uma amostra de 76 crianças com idade entre 4 e 24 meses, no período de fevereiro a dezemb (mais) ro de 2005. Os desenvolvimentos mental e motor foram avaliados pela Escala de Desenvolvimento Infantil de Bayley II. Após a suplementação observou-se um aumento significante na concentração de hemoglobina, apenas no grupo de lactentes com hemoglobina inicial Resumo em inglês This study analyzed the effectiveness of weekly iron supplementation on hemoglobin concentration, nutritional status, and mental and motor development of infants at four public daycare centers in Recife, Pernambuco State, Brazil. This was a before-after intervention study conducted with weekly iron supplementation for six months in a sample of 76 infants in the 4 to 24 month age group, from February to December 2005. Mental and motor development was assessed through the B (mais) ayley Scale of Infant Development II. After supplementation, a significant increase was observed in hemoglobin concentration in the group of infants with initial hemoglobin level
2007-04-01
Resumo em português Avaliaram-se as concentrações plasmáticas de triglicérides, colesterol, aspartato transaminase (AST) e progesterona (P4) em vacas Nelore não lactantes com elevado escore corporal, superovuladas com diferentes protocolos. Foram utilizados três grupos de animais, G1 (n=11), G2 (n=8) e G3 (n=5), superovulados com 500UI de FSH, 200mg e 180mg de FSH (hormônio folículo estimulante), respectivamente, em doses decrescentes, duas vezes ao dia, durante quatro dias. As amost (mais) ras de sangue foram coletadas antes da superovulação (A), no terceiro dia da superovulação (B), no momento da inseminação artificial (C) e na coleta dos embriões (D). As concentrações de triglicérides, AST e colesterol foram verificados por espectrofotometria, e a de progesterona (P4) por radioimunoensaio. Não houve alteração (P>0,05) na concentração de triglicérides, AST e colesterol entre as amostras. Não houve efeito (P>0,05) do protocolo de superovulação sobre a concentração de triglicérides, AST e P4 nas diferentes amostras. O G2 apresentou menor concentração de colesterol (P Resumo em inglês The purpose of this research was to evaluate the concentration of tryglicerides, cholesterol, aspartate transaminase (AST) and progesterone (P4) in embryo donor Nelore cows superovulated with different protocols. Twenty four donors were randomly distributed in three groups: group 1 (n=11), donors superovulated with 500UI of FSH and group 2 (n=8) and group 3 (n=5) respectively with 200mg and 180mg of FSH, in decreasing doses, twice a day, during four consecutive days. Bloo (mais) d samples were collected before superovulation (A), in the third day of superovulation (B), at the artificial insemination time (C) and at the embryo collection time (D). The concentrations of tryglicerides, aspartate transaminase (AST) and cholesterol were measured by spectrophotometry and progesterone (P4) by radioimmunoassay. There was no alteration (P0.05) of the superovulation protocol on the concentration of tryglicerides, AST and P4 in the samples. In the samples A and B of group 2 the concentration of cholesterol was lower (P
2002-12-01
Resumo em inglês In the last three decades carbonyl compounds, aldehydes and ketones, have received a great deal of attention due to their strong influence on photochemical smog formation and their recognized adverse human health effects. Carbonyl compounds are directly emitted into the atmosphere by combustion sources and also produced from photochemical oxidation of hydrocarbons and other organic compounds. In this paper it is presented a general overview about the carbonyl compounds sources, reactivity, concentration levels and toxicological effects.
2006-10-01
Resumo em inglês The aim of this work is to present the theoretical and experimental aspects of the mirage effect technique. We are especially interested in the concentration mirage effect, which is a powerful tool in the study of electrochemical reactions that produce ionic movements close to electrodes and to get some fundamental information on mass transport and charge transfer during electrochemical processes. Limitations of this technique are discussed as well as the recent attempts to overcome them.
2009-08-01
Resumo em português As substâncias húmicas podem influenciar direta ou indiretamente o metabolismo das plantas, alterando assim o seu crescimento. O objetivo deste trabalho foi avaliar o efeito de substâncias húmicas (SH) no crescimento e na concentração de nutrientes em plantas de feijão (Phaseolus vulgaris, L.) e nos parâmetros cinéticos de absorção de K. O experimento foi realizado em bancada de laboratório, com luz artificial. As plantas cresceram em vasos contendo solução (mais) nutritiva completa acrescida de cinco doses (0; 2,5; 5; 10; e 20 mg L-1 de C) de SH solúveis em meio alcalino (ácido húmico + ácido fúlvico), extraídos de amostra de carvão mineral da mina de Candiota, RS, da Companhia Riograndense de Mineração, num delineamento completamente ao acaso, com três repetições. Aos 28 dias de cultivo, foram avaliados parâmetros cinéticos de absorção de K, massa da parte aérea e da raiz seca, teores de N, P, K, Ca e Mg no tecido da parte área e as características morfológicas de raízes (comprimento, área e raio). Os resultados evidenciaram que a adição de SH extraída de carvão mineral estimulou o crescimento do feijão e afetou a cinética de absorção de K. A produção de massa da parte aérea seca das plantas mostrou resposta quadrática à adição de substâncias húmicas, atingindo valor máximo na dose equivalente a 11 mg L-1 de C, enquanto a massa das raízes secas aumentou linearmente em até 41 %, com as doses testadas. As características morfológicas de raiz e o estado nutricional das plantas não foram significativamente afetados pelas SH. Os parâmetros cinéticos de absorção de K, Imáx, Cmín e Km, decresceram linearmente com o aumento das doses de SH, causando redução na taxa de absorção de K nas concentrações deste nutriente na solução superiores a 10 μmol L-1. Resumo em inglês Humic substances can influence plant metabolism direct or indirectly, thus modifying its growth. The objective of this study was to evaluate the effect of humic-like substances (HS) on kinetics of K uptake, nutrient concentration and growth of common bean (Phaseolus vulgaris, L.). The experiment was performed on a laboratory bench with controlled light conditions. Plants were grown in pots with complete nutrient solution enriched with five levels (0; 2.5; 5; 10 and 20 mg (mais) L-1 of C) of alkaline soluble humic-like substances (fulvic and humic acids), extracted from mineral charcoal samples from the Candiota mine (Companhia Riograndense de Mineração), in the State of Rio Grande do Sul, Brazil. The experiment was set up in a randomized design, with three replications. After 28 days of plant growth, kinetics parameters of K uptake, shoot and root dry weight, shoot tissue concentration of nutrients (N, P, K, Ca and Mg) and root morphological parameters (length, area and radius) were evaluated. The results showed that the application of charcoal-extracted humic substances stimulated common bean growth and influenced the kinetics parameters of K uptake. A quadratic response to HS was observed in shoot dry weight, which reached the highest values at 11 mg L-1 of C, whereas root dry mass increased linearly up to 41 % along the increasing HS concentration in solution. Root morphological parameters and nutritional conditions of plants were not significantly affected by HS. The kinetic parameters of K uptake, Imax, Cmin and Km, decreased with increasing HS concentration, causing reduction in K influx when the K concentration in solution exceeded 10 μmol L-1.
2004-10-01
Resumo em português Foi proposto recentemente que a solubilidade protéica in vitro com pepsina na concentração de 0,0002% é melhor que em concentrações maiores, para melhor classificar a qualidade protéica de farinhas de origem animal (FOA). Entretanto, nessa concentração, desconhece-se qual é o intervalo que melhor exprime a qualidade por meio da solubilidade protéica das FOA. Este trabalho foi conduzido com o objetivo de identificar os valores da solubilidade protéica de farinh (mais) as de subprodutos do abate de aves (FSA), utilizadas como modelo experimental. As fontes protéicas foram duas FSA e caseína (considerada padrão com 100% de solubilidade protéica). Todas as farinhas foram autoclavadas a 120ºC, durante 0, 10, 20, 40 e 80 minutos. As concentrações utilizadas da pepsina em solução de HCl 0,0744N foram de 0,0002 e 0,02%. O delineamento experimental foi o de blocos casualizados em esquema fatorial 3 (fontes) x 5 (temperaturas) x 2 (concentrações), com quatro repetições para a enzima na concentração de 0,0002% e duas repetições para a concentração de 0,02%. Foram determinados os valores de solubilidade protéica in vitro em solução ácido/pepsina e energia metabolizável in vivo das FSA. Os resultados indicaram que, na concentração de pepsina de 0,0002%, os valores de boa qualidade das FSA estão acima de 55%. Da mesma forma, solubilidades próximas a 84% podem ser consideradas boas, mas decaem em solubilidade e são consideradas ruins se tiverem em torno de 67% de solubilidade protéica em pepsina a 0,02%. Resumo em inglês It was recently proposed that the in vitro protein solubility is better to classify animal by-product meals (ABP) using pepsin concentration of .0002% than with higher concentrations. However on this concentration no reference value exists to express ABP quality based on protein solubility. The objective of this study was to obtain protein solubility values for poultry by-product meals (PBP), as model to ABP. Two PBP and casein (considered 100% soluble protein) were used (mais) as protein sources. All meals were autoclaved at 120ºC, during 0, 10, 20, 40 and 80 minutes. Concentrations of pepsin on acid HCl 0,0744N were 0.0002 and 0.02%. The experiment was carried out according to a completely randomized design with factorial scheme 3 (sources) x 5 (temperatures) x 2 (concentrations), with four replications for enzyme concentration of 0.0002% and two replications for enzyme at 0.02%. It were determined the in vitro protein solubility values on acid/pepsin solution and the in vivo metabolizable energy of PBP meals. The results indicated that on pepsin concentration of 0.0002%, the values of good quality PBP are over 55%. In the same way, solubility close to 84% could be considered good quality source, but decreasing solubility are considered bad quality with 67% on pepsin at concentration of 0.02%.
2004-06-01
Resumo em português Lipase de Candida rugosa na forma livre foi usada na síntese de butirato de butila pela esterificação direta de n-butanolcom ácido butírico. Um planejamento fatorial completo 2(4) foi empregado para determinar a influência da razão molar do álcool para ácido (1: 0,5-2,5), concentração de agente dessecante (0-20%), concentração de enzima (40-80 mg) e temperatura de incubação (30-60 °C) no rendimento de esterificação. A concentração de agente dessecante (mais) foi o fator mais significativo na esterificação, sendo sua influência negativa. O progresso da esterificação foi favorecido para substratos contendo ácido em excesso, mesmo em baixa concentrações de enzima (40 mg), sendo a conversão de 50%. Na região avaliada, a formação do butirato de butila (26,67 g/L) foi maximizada para razão molar (1:2,5), ausência de agente dessecante, concentração de enzima (80 mg) e temperatura de incubação de 30 °C. Resumo em inglês Free lipase from Candida rugosa was used for the synthesis of butyl butyrate by direct esterification of butyric acid and butyl alcohol. A full factorial experimental design (2(4)) was employed to determine the effect of alcohol to acid ratio (1: 0.5-2.5), water adsorbent concentration (0-20%), enzyme concentration (40-80 mg) and incubation temperature (30-60 °C) on the esterification yield. Water adsorbent concentration has been found to be the most significant factor o (mais) n the esterification reaction and its influence was negative. The extent of esterification was higher for substrates containing acid in excess even with a low enzyme concentration of 40 mg and 50% conversion was observed. The maximum predicted values for butyl butyrate yield (92.67%) can be attained with substrate containing acid in excess (molar ratio alcohol to acid 1:2.5), 80 mg enzyme concentration in the absence of water adsorbent at temperature incubation of 30 °C.
2010-01-01
Resumo em português A intensidade da cor verde da folha pode ser alternativa para estimar a concentração de N na planta, devido à relação entre o teor de clorofila e o de N no tecido foliar. Objetivou-se neste trabalho avaliar índices da cor verde da grama esmeralda obtidos da análise da imagem digital e pelo uso do clorofilômetro para predizer o estado nutricional em N fornecido pelo lodo de esgoto. O experimento foi instalado e desenvolvido em uma propriedade comercial de grama esm (mais) eralda, localizada na cidade de Itapetininga (SP). O delineamento experimental foi em blocos casualizados, com quatro repetições e cinco doses de lodo de esgoto: 0, 10, 20, 30 e 40 Mg ha-1, base seca. As doses de lodo aplicadas correspondem a 100, 200, 300 e 400 kg ha-1 de nitrogênio disponível. Foram avaliadas as concentrações de N e a intensidade de coloração verde da folha pelo uso do clorofilômetro (ICV) e por meio da análise da imagem digital (G, H e ICVE) aos 45, 105 e 165 dias após a aplicação do lodo. Os valores de intensidade obtidos foram correlacionados com a concentração de N na lâmina foliar e com a taxa de cobertura do solo determinada nas mesmas épocas. A aplicação de doses de lodo de esgoto proporcionou aumento dos índices de cor verde e da concentração de N nas folhas da grama esmeralda. A concentração de N na lâmina foliar pode auxiliar a adubação nitrogenada em cobertura, pois proporcionou altas correlações com a taxa de cobertura do solo. O matiz (H) obtido com a imagem digital e a intensidade de cor verde da folha (ICV) obtida com o clorofilômetro correlacionaram-se com a concentração de N e com a taxa de cobertura do solo e, dessa forma, podem servir como índices na recomendação da adubação nitrogenada. Resumo em inglês The intensity of leaf green color can be an alternative to estimate the N concentration because of the relationship between chlorophyll level and N in leaf tissue. The objective of the work was to assess green index of the zoysiagrass from the digital imaging analysis and the use of chlorophyll meter to predict the nitrogen nutritional status in sewage sludge fertilized areas. The experiment was carried out on a commercial property of zoysiagrass, located in the county of (mais) Itapetininga, State of São Paulo. The experimental design was completely randomized, with five sewage sludge doses: 0, 10, 20, 30 and 40 Mg ha-1, on dry basis (equal to 0, 100, 200, 300 and 400 kg ha-¹) of N available and four replications. The N concentration and green hue intensity were evaluated by using chlorophyll meter (GHI) and by the digital image analysis (G, H and DGCI) at 45th, 105th and the 165th days after sewage sludge application. The intensity values were correlated with the N concentration in the leaf blade and with the soil cover rate determined in the same season. The application of sewage sludge doses increased the green rates and the N concentration in the Zoysia grass leaves. The N concentration leaf can help the nitrogen top-dressed application because it has high correlation with the soil cover rate. The hue (H) obtained with the digital image and green hue intensity (GHI) obtained with the chlorophyll meter are correlated with N concentration and with the soil cover rate and can serve as an index to assist in the recommendation of nitrogen fertilization.
2010-12-01
Resumo em português Este estudo foi realizado com o objetivo de avaliar a concentração plasmática de N-ureico, o número de ovulações e o diâmetro do folículo ovulatório de ovelhas da raça Santa Inês submetidas a sobrealimentação com fontes de proteína de diferentes degradabilidades ruminais. Quarenta e quatro ovelhas com o estro sincronizado receberam dietas isoproteicas, formuladas com farelo de soja (n=24) ou com glúten de milho e farelo de algodão (n=20) durante 28 dias an (mais) tes da ovulação. Os animais foram distribuídos em delineamento de blocos, com os blocos formados por três faixas de escore de condição corporal. O ganho de peso vivo e de escore de condição corporal, o peso vivo e o escore de condição corporal no 28º dia do experimento, a concentração plasmática de N-ureico, o número de ovulações e o diâmetro do folículo ovulatório não diferiram entre as ovelhas submetidas à sobrealimentação com farelo de soja ou com glúten de milho e farelo de algodão. As ovelhas que receberam sobrealimentação com farelo de soja apresentaram maior concentração plasmática de N-ureico nos dias 7 e 14 e menor no dia 28 em comparação às que receberam sobrealimentação com glúten de milho e farelo de algodão (interação dieta vs dia). O fornecimento de uma dieta com menor teor de proteína degradável no rúmen não reduz concentração plasmática de N-ureico nem altera o número de ovulações e o diâmetro do folículo ovulatório. Resumo em inglês This study aimed at evaluating plasma concentration of urea nitrogen, the number of ovulations and the diameter of ovulatory follicle of Santa Ines ewes submitted to flushing with sources of protein with different ruminal degradabilities. Forty-four estrus-synchronized ewes were fed isoprotein diets composed of soybean meal (n = 24) or corn gluten meal and cottonseed meal (n = 20) for 28 days before ovulation. Animals were distributed in a block design in which the blocks (mais) were formed by three score ranges of body condition score. Body weight and body condition score gains, body weight and body condition score on the 28th experimental day, urea nitrogen plasma concentration, number of ovulations and diameter of the ovulatory follicle did not differ among ewes submitted to flushing with soybean meal or with corn gluten and cottonseed meal. Ewes under soybean meal flushing showed higher urea nitrogen plasma concentration on days seven and 14 and lower concentration on the 28th day when compared to those fed corn gluten and cottonseed meal (day vs. diet interaction). The supply of one diet with lower content of ruminal degradable protein does not reduce urea nitrogen plasma concentration neither alters the number of ovulations and diameter of ovulatory follicle.
2007-02-01
Resumo em português OBJETIVO: Avaliar os efeitos da evaporação e da pasteurização do leite humano na sua composição bioquímica e imunológica e em sua osmolaridade. MÉTODOS: As amostras de leite humano maduro foram divididas em quatro grupos de estudo: leite humano in natura, leite humano pasteurizado, leite humano evaporado a 70% do volume inicial e leite humano pasteurizado e evaporado a 70%, com 12 diferentes amostras de leite em cada grupo. Das amostras dos grupos, foram dosadas (mais) as concentrações de sódio, potássio, cálcio, fósforo, magnésio, proteína, gordura, lactose, imunoglobulina A e osmolaridade. RESULTADOS: A pasteurização do leite humano não mostrou alterações estatisticamente significantes na concentração dos elementos sódio, potássio, cálcio, fósforo, magnésio, proteína, gordura, lactose, nem na osmolaridade; no entanto, mostrou redução significante na concentração média de imunoglobulina A. A evaporação mostrou aumento estatisticamente significativo de 38% em média na concentração dos elementos sódio, potássio, cálcio, fósforo, magnésio, proteína, gordura e lactose e redução média de 45% na concentração da imunoglobulina A, sem alteração significativa da osmolaridade em relação ao leite sem processamento. CONCLUSÃO: Através da evaporação a 70% do volume inicial do leite humano, pode ser obtido leite humano com condições de satisfazer as necessidades nutricionais preconizadas para o recém-nascido pré-termo, com exceção do cálcio e do fósforo. Resumo em inglês OBJECTIVE: To assess the effects of evaporation and pasteurization of human milk on its biochemical and immunological composition and on its osmolarity. METHODS: The samples of mature human milk were categorized into four study groups: in natura human milk, pasteurized human milk, human milk evaporated at 70% of the baseline volume and human milk pasteurized and evaporated at 70%, with 12 different samples of milk in each group. The samples were used to determine the conc (mais) entrations of sodium, potassium, calcium, phosphorus, magnesium, protein, fat, lactose, immunoglobulin A and osmolarity. RESULTS: The pasteurization of human milk did not show statistically significant changes in the concentration of sodium, potassium, calcium, phosphorus, magnesium, protein, fat, lactose, or in osmolarity; however, it showed remarkable reduction in the mean concentration of immunoglobulin A. Evaporation had a mean increase of 38% in the concentration of sodium, potassium, calcium, phosphorus, magnesium, protein, fat and lactose and mean reduction of 45% in the concentration of immunoglobulin A, without significant change in osmolarity in unprocessed milk. CONCLUSION: By evaporation at 70% of the baseline value of human milk, it is possible to obtain human milk that meets the nutritional requirements recommended for preterm infants, except for calcium and phosphorus.
Otimização da produção de biodiesel a partir de óleo de coco babaçu com aquecimento por microondas
2009-12-01
Resumo em português As reações sob aquecimento por microondas geralmente apresentam significativa redução no tempo de reação e elevados rendimentos. Portanto, o objetivo desse trabalho foi adaptar um forno de microondas doméstico de forma adequada e segura para realização de reações de transesterificação, e otimizar o processo de produção de biodiesel por microondas usando óleo de coco babaçu como matéria prima. Para este fim, foi usado um planejamento composto central no q (mais) ual se variou o tempo de irradiação, concentração de KOH e razão óleo:metanol. Análises estatísticas foram feitas para avaliarem a significância do modelo usado. As condições experimentais ótimas foram: razão óleo:metanol, 8,59, concentração de KOH, 2,19%, tempo de irradiação, 70 segundos, dando rendimento de aproximadamente 100%. Resumo em inglês Reactions under microwave heating present reduced reaction times and larger yields. Therefore, this work is aimed at adapting a domestic microwave oven and optimizing the transesterification reaction used in biodiesel production with microwave heating, using babaçu coconut oil as raw material. It was used a central composite design for varying irradiation time, KOH concentration, and oil:methanol ratio. Statistical analyses were performed in order to assess the significa (mais) nce of the model used. The optimized experimental conditions were: oil:methanol ratio, 8.59; KOH concentration, 2.19 %; and irradiation time, 70 seconds, giving an yield of approximately 100% regarding esters formation.
2009-09-01
Resumo em português Utilizaram-se nove novilhos Nelore fistulados no rúmen mantidos em nove piquetes de capim-marandu (Brachiaria brizantha cv. Marandu) sob suplementação diária (sete vezes por semana); de segunda a sexta-feira (cinco vezes por semana); ou às segundas, quartas e sextas-feiras (três vezes por semana). Amostras de líquido ruminal foram coletadas em dois dias: um dia em que todos os animais receberam suplemento (dia 1) e outro subsequente, no qual somente os animais sob (mais) suplementação diária receberam suplemento (dia 2). A frequência de suplementação não alterou a ingestão de matéria seca de forragem, a ingestão de matéria seca total e a digestibilidade total da matéria seca. As variáveis foram afetadas somente pelo período, com redução significativa do mês de março para o mês de maio. A frequência de suplementação não afetou o pH ruminal. Para N-NH3 ruminal, observou-se interação frequência de suplementação X dia de coleta X horário de coleta. No dia 1 a concentração de N-NH3 não diferiu entre os horários após a suplementação entre os animais sob suplementação diária, enquanto no dia 2 houve um pico de produção de N-NH3 3 horas após a suplementação. Entre os animais sob suplementação cinco vezes por semana, a diferença entre os dias 1 e 2 foi ocasionada pelo tempo 12 do dia 2 (7 mg/dL). Na suplementação três vezes por semana, no dia 1 o pico de N-NH3 ocorreu 3 a 9 horas após a suplementação. A frequência de suplementação afetou somente a concentração de AGCC totais no dia 1 e a concentração de ácido butírico no dia 2. O mês do ano não afeta o pH e a concentração de N-NH3, mas os AGCC diminuem significativamente do mês de março para o mês de maio. Resumo em inglês Nine ruminally fistulated Nellore steers were located in nine paddocks of palisade grass (Brachiaria brizantha cv. Marandu) pasture under daily supplementation (seven times per week), from Monday to Friday (five times per week) or Monday, Wednesday and Friday (three times per week). Ruminal fluid was sampled on two consecutive days. On the first day, all the animals that were supplemented (D1) and other subsequent day in which only for the animals under daily supplementat (mais) ion received the supplement (D2). The supplementation frequency did not affect the forage DMI, total DMI and DMD. The DMI and DMD were influenced by the experimental period, with reduction from March to May. Ruminal pH was not affected by the supplementation frequency. Supplementation frequency X collection day X collection hour interaction was observed for ruminal NH3-N. No difference in the D1 was observed in NH3-N concentration among the hours after supplementation in the daily supplementation frequency, while in the D2 there was a peak of NH3-N production 3 hours after supplementation. Among the animals under five times per week supplementation, the difference between D1 and D2 was due to the time 12 of the D2 (7 mg/dL). In the three times per week, the NH3-N concentration in D1 peaked at 3-9 hours after supplementation. The supplementation frequency only affected total SCFA concentration in the D1 and butyric acid concentration in the D2. The month of the year did not affect the ruminal pH and NH3-N concentration. However, the SCFA concentration was significantly reduced from March to May.
2008-06-01
Resumo em português Objetivou-se avaliar o efeito de fontes de fósforo (Yoorin®, Superfosfato simples + superfosfato triplo e testemunha) em pastagem de capim-mombaça sobre as concentrações de nutrientes da excreção animal em condições de pastejo. O método de pastejo foi o de lotação contínua com cargas variáveis. Utilizaram-se novilhos mestiços com peso médio de 300 kg distribuídos em delineamento inteiramente casualizado, com parcelas subdivididas, cada uma com quatro repe (mais) tições. A produção média de urina animal e a concentração de potássio na urina foram maiores nos animais do tratamento Yoorin e variaram de 7,2 a 20,4 L/animal/dia e 180 a 310 g/L, respectivamente. Os excrementos dos animais dos tratamentos testemunha e SFS + SFT apresentaram maior teor de nitrogênio e fósforo na urina em comparação aos do tratamento Yoorin (154 a 195; 0,2 a 0,29 g/L, respectivamente). A quantidade média de nitrogênio e potássio na urina foi maior nos animais dos tratamentos Yoorin e SFS + SFT em comparação aos do tratamento testemunha (de 51 a 99 e 46 a 149 g/animal/dia, respectivamente). A concentração de cálcio e a quantidade média de fósforo e cálcio na urina foram semelhantes entre os tratamentos. A produção de fezes, as concentrações e as quantidades de nitrogênio, potássio e cálcio nas fezes foram semelhantes entre os tratamentos. A quantidade média de fósforo foi maior nas fezes dos animais mantidos nas pastagens fertilizadas com SFS + SFT e Yoorin em comparação aos da pastagem testemunha e variou de 7,5 a 11,6 g/animal/dia. O retorno de nutrientes por meio da excreção animal contribuiu no período experimental com 73, 87, 6 e 28 kg/ha de nitrogênio, potássio, fósforo e cálcio, respectivamente. Os animais da pastagem fertilizada com Yoorin apresentaram maior produção diária de urina, além de mais alta concentração de potássio na urina. Resumo em inglês The objective of this experiment was to evalute the effects of phosphorus sources (Yoorin®, Ordinary Superphosphate (SS) + Triple Superphosphate (TS) and control) on the concentration and amount of N, P, K, and Ca in the excreta of crossbred steers under grazing conditions on mombaça grass (Panicum maximum Jacq. cv. mombaça) pasture. The grazing method was the continuous stocking with variable stocking rate, and the animals used were crossbred with average live weight (mais) of 300 kg. It was used a complete randomized design in split plot with four replications. Urine production and K concentration were high for animals grazing on Yoorin fertilized pastures compared to other treatments; urine production ranged from 7.2 to 20.4 L/animal/day and K urine concentration ranged from 180 to 310 g/L. Animals grazing on the control and SS + TS treatments presented greater N and P urine concentration than the ones grazing on Yoorin fertilized pastures, ranging from 154 to 195 g N/L and 0.2 to 0.29 g P/L, respectively. Average N and K amount excreted via urine was greater for animals grazing on Yoorin and SS + TS treatments compared to control treatment, ranging from 51 to 99 g N/animal/dia and 46 to 49 g K/animal/dia, respectively. Average Ca concentration and P and Ca amount excreted via urine were similar among treatments. Average fecal production and N, K, Ca concentrations and amounts were similar among treatments. Average P amount was greater for SS + TS and Yoorin treatments compared to the control, ranging from 7.5 to 11.6 g P/animal/day. Nutrient return via animal excreta contributed in the experimental period with 73, 87, 6, and 28 kg/ha of N, K, P, and Ca, respectively. Animals on Yoorin fertilized pastures presented greater urine production and greater K urine concentration and amount.
2006-08-01
Resumo em português Estudou-se a diferença entre a produção de gases (PG) e a degradação da matéria seca (DMS) para substratos com diferentes quantidades de carboidratos solúveis avaliados pela técnica in vitro de produção de gases. Foram utilizados cinco substratos (cana-de-açúcar, silagem de milho, capim-colonião, milho em grão e ração comercial para vacas em lactação) antes e após a retirada parcial dos carboidratos solúveis (lavados). A PG foi maior e a DMS menor para (mais) o material lavado. A concentração de carboidratos solúveis influenciou os resultados obtidos pela técnica de produção de gases. Resumo em inglês The difference between the gas production (GP) and the dry matter degradation (DMD) of substrates with different amounts of soluble carbohydrates using the in vitro gas production technique was studied. Five substrates (sugarcane, maize silage, Panicum maximum grass, corn grain, 20% CP commercial lactating cow ration and soybean meal) and the same substrates with part of its soluble carbohydrate removed (washed materials) were evaluated. The GP was higher and DMD was lowe (mais) r for washed materials than for the original materials. The carbohydrate concentration affects the results of the gas production technique.
2010-06-01
Resumo em português O objetivo deste estudo foi avaliar os níveis de flúor na água de abastecimento público da Ilha de São Luís (MA). Aplicou-se uma amostragem estratificada, considerando-se as estações de tratamento de água (06) e os bairros abastecidos (46). A análise dos teores de flúor na água foi feita através de um eletrodo específico. A concentração nas amostras variou de 0,05 a 0,84 ppm de flúor. Apenas uma estação de tratamento (Italuís) apresentou-se dentro do l (mais) imite aceitável de fluoretação. A fluoretação da água de abastecimento público na Ilha de São Luís necessita de ajustes para se obter prevenção da cárie, evidenciando a importância de um controle externo para avaliação dos teores de flúor. Resumo em inglês The aim of the present study was to evaluate the fluoride levels in public water supply in São Luís island, Maranhão State, Brazil, during the month of October of 2006. A stratification sampling was applied, considering the water treatment station (06) and the different districts (46). For fluoride analysis it was used a specific ion electrode. The fluoride concentration varied for 0.05 to 0.84 ppm. Only one water treatment station (Italuís) presented an ideal concent (mais) ration of fluoride. It was concluded that the fluoride levels need adjustments, evidencing that it is essential an external control for monitoring of those levels in public water supply of São Luis.
2010-06-01
Resumo em português O objetivo deste estudo foi avaliar os níveis de flúor na água de abastecimento público da Ilha de São Luís (MA). Aplicou-se uma amostragem estratificada, considerando-se as estações de tratamento de água (06) e os bairros abastecidos (46). A análise dos teores de flúor na água foi feita através de um eletrodo específico. A concentração nas amostras variou de 0,05 a 0,84 ppm de flúor. Apenas uma estação de tratamento (Italuís) apresentou-se dentro do l (mais) imite aceitável de fluoretação. A fluoretação da água de abastecimento público na Ilha de São Luís necessita de ajustes para se obter prevenção da cárie, evidenciando a importância de um controle externo para avaliação dos teores de flúor. Resumo em inglês The aim of the present study was to evaluate the fluoride levels in public water supply in São Luís island, Maranhão State, Brazil, during the month of October of 2006. A stratification sampling was applied, considering the water treatment station (06) and the different districts (46). For fluoride analysis it was used a specific ion electrode. The fluoride concentration varied for 0.05 to 0.84 ppm. Only one water treatment station (Italuís) presented an ideal concent (mais) ration of fluoride. It was concluded that the fluoride levels need adjustments, evidencing that it is essential an external control for monitoring of those levels in public water supply of São Luis.
2011-01-01
Resumo em português O presente trabalho teve como objetivos avaliar os sinais clínicos, as concentrações do sulfeto de hidrogênio ruminal e as alterações anatomopatológicas associadas à intoxicação experimental por enxofre em bovinos. Foram utilizados dez bezerros mestiços leiteiros, sendo que quatro bovinos ingeriram ração sem sulfato de sódio (G1) e seis consumiram ração com sulfato de sódio (G2). Exames clínicos (temperatura retal, frequência cardíaca e respiratória e (mais) motricidade ruminal) e laboratoriais (hemograma, fibrinogênio, proteína plasmática, pH do fluido ruminal, concentração do sulfeto de hidrogênio ruminal, líquido cerebrospinal e histopatológico) foram realizados. A temperatura retal, frequência cardíaca, hemograma, fibrinogênio, proteína plasmática, pH do fluido ruminal e os valores do líquido cerebrospinal estavam dentro dos valores de referência para a espécie. Taquipnéia, hipomotricidade ruminal e elevados valores de sulfeto de hidrogênio ruminal foram observados nos bezerros do grupo G2. Um bezerro do grupo G2 apresentou sinais neurológicos e lesões histopatológicas de PEM. Dois animais de cada grupo foram eutanasiados. Lesões microscópicas foram observadas nos bezerros do G2. Histologicamente as alterações observadas foram necrose neuronal cortical e lesões hemorrágicas nos núcleos basais, tálamo, mesencéfalo, ponte e bulbo. O protocolo experimental constituído por uma dieta rica em carboidrato de alta fermentação, baixa quantidade de fibra efetiva e altos níveis de enxofre (0,52%) ocasionou alterações clinicas e histológicas e elevadas concentrações de sulfeto de hidrogênio ruminal compatíveis com quadro de intoxicação por enxofre. Resumo em inglês The aims of this study were to evaluate the clinical signs, the ruminal hydrogen sulfide concentration and the histological lesions induced by sulfur toxicosis in cattle. Ten crossbred calves were fed an experimental diet, four without sodium sulfate (G1) and six with (G2). The calves were submitted to clinical (rectal temperature, cardiac and respiratory rate and ruminal motricity) and laboratorial (hemogram, fibrinogen, total plasma protein, ruminal fluid pH, ruminal hy (mais) drogen sulfide concentration, cerebrospinal fluid and histopathological) evaluations. Rectal temperature, cardiac rate, hemogram, fibrinogen, total plasma protein, ruminal fluid pH and cerebrospinal fluid values were within normal reference ranges in animals from both groups. Ruminal hypomotricity and increased respiratory rate and ruminal hydrogen sulfide concentration occurred in G2 animals. One out of six calves in G2 developed neurological signs and lesions of PEM. Two calves of each Group were euthanized. Microscopic lesions of PEM were observed in G2 animals. Histologically there were cortical neuronal necrosis and hemorrhagic lesions in basal nuclei, thalamus, midbrain, pons and medulla oblongata. The experimental model consisting of a diet with high carbohydrate and low in long fiber content with high sulfur concentrations (0.52%) resulted in clinical and histological abnormalities and high ruminal hydrogen sulfide concentration consistent with sulpur toxicosis in cattle.
2005-12-01
Resumo em inglês Nitric oxide (•NO) is a substance that acts as a second-messenger and is associated with a number of important physiological functions such as regulation of the vascular tonus, immune modulation and neurotransmission. As a physiological mediator, alteration of its concentration level may cause pathophysiological disfunctions such as hypertension, septic shock and impotence. Possible therapeutic approaches are being developed to control NO levels in vivo. We review herein (mais) the main physical and chemical properties of •NO, its biological functions and available chemical interventions to reduce and increment its physiological concentration levels. Recent developments in the field are also highlighted.
2007-10-01
Resumo em português Foram avaliados os efeitos do óxido de cálcio aplicado no momento da ensilagem nas doses de 0,5; 1 e 2% sobre a composição química de silagens de cana-de-açúcar durante a fermentação e pós-abertura. Antes da ensilagem, doses crescentes de óxido promoveram redução dos teores de FDN, FDA e lignina e aumento da hemicelulose e da digestibilidade in vitro da matéria seca (DIVMS). No momento da abertura dos silos, os teores de FDN e FDA foram superiores aos observ (mais) ados antes da ensilagem e menores nas silagens com doses mais altas de aditivo. Nesta mesma fase, quanto maior o nível do aditivo maior a DIVMS. Do momento da abertura ao 3º dia, não houve alteração significativa nos teores de PB, FDN, FDA, lignina e hemicelulose ou na DIVMS. O teor de FDN das silagens controle e com 0,5% de aditivo aumentou do 3º ao 6º dia. Silagens com 0,5% de cal tiveram aumento do teor de FDN também do 6c ao 9ºdia, enquanto, nas silagens com 1% de cal, esse aumento ocorreu do 3º ao 9º dia e, nas silagens com 2%, não houve alteração após abertura. Na silagem com 2% de óxido de cálcio, a maior recuperação de matéria seca digestível verdadeira e de CNF ocorreu na ensilagem e, naquelas com 1 e 2% de aditivo, após a abertura do silo. A adição de cal virgem reduziu o teor de FDN das silagens em todos os momentos e manteve o teor de FDN mais estável após abertura. Resumo em inglês This research evaluated the addition of three levels of calcium oxide (0.5, 1.0, and 2.0%) at the sugar cane ensiling. Chemical composition was evaluated during fermentation and after silo opening. Before ensiling, increasing levels of calcium oxide reduced the NDF, ADF, and lignin concentration, and increased hemicellulose and in vitro true dry matter digestible-IVTDMD. At the silo opening, it was observed greater NDF and ADF concentration, compared to values observed be (mais) fore ensiling. The smallest values were observed on the treatments with greater additive application. In this same phase, the highest additive level resulted in the highest IVTDMD. The CP, NDF, ADF, lignin, hemicellulose, and IVTDMD did not present significant changes from the silos opening until the 3rd day of air exposure. The control and 0.5% calcium oxide silage presented significant increase on the NDF concentration from the 3rd to the 6th day of air exposure. Silages treated with 0.5% of calcium oxide increased the NDF concentration from the 6th to the 9th day. Silage treated with 1.0% of calcium oxide changed the composition from the 3rd to the 9th day. Silages with 2.0% of calcium oxide did not change the NDF concentration after silos opening. The IVTDMD and non-structural carbohydrates recovery increased on the silages treated with 2.0% of the additive at the ensiling and on those silages treated with 1.0 and 2.0%, the recovery was greater after the silo opening. Addition of calcium oxide reduced silage NDF concentration in all the phases, and it maintained more stable the NDF values after silo opening.
2011-01-01
Resumo em inglês The concentration of 14 organic acids of 50 sugarcane spirits samples was determined by gas chromatography using flame ionization detection. The organic acids analytical quantitative profile in stills and column distilled spirits from wines obtained from the same must were compared. The comparison was also carried in "head", "heart" and "tail fractions of stills distilled spirits. The experimental data were analyzed by Principal Components Analysis (PCA) and pointed out t (mais) hat the distillation process (stills and column) strongly influences the lead spirits' organic acid composition and that producers' operational "cuts off" to produce "tail", "heart" and "head", fractions should be optimized.
2009-01-01
Resumo em inglês The most widespread literature for the evaluation of uncertainty - GUM and Eurachem - does not describe explicitly how to deal with uncertainty of the concentration coming from non-linear calibration curves. This work had the objective of describing and validating a methodology, as recommended by the recent GUM Supplement approach, to evaluate the uncertainty through polynomial models of the second order. In the uncertainty determination of the concentration of benzatone (mais) (C) by chromatography, it is observed that the uncertainty of measurement between the methodology proposed and Monte Carlo Simulation, does not diverge by more than 0.0005 unit, thus validating the model proposed for one significant digit.
2007-10-01
Resumo em inglês Green coconut shells were treated with acid, base and hydrogen peroxide solutions for 3, 6, 12 and 24 h for removing toxic metals from synthetic wastewater. The removal of ions by the adsorbent treated with 0.1 mol L-1 NaOH/ 3h was 99.5% for Pb2+ and 97.9% for Cu2+. The removal of Cd2+, Ni2+, Zn2+, using adsorbent treated with 1.0 mol L-1 NaOH/3 h, was 98.5, 90.3 and 95.4%, respectively. Particle size, adsorbent concentration and adsorption kinetics were also studied. An (mais) adsorbent size of 60-99 mesh and a concentration of 30-40 g/L for 5 min exposure were satisfactory for maximum uptake of Pb2+, Ni2+, Cd2+, Zn2+ and Cu2+ and can be considered as promising parameters for treatment the aqueous effluents contaminated with toxic metals.
2007-01-01
Resumo em inglês The remediation of groundwater containing organochlorine compounds was evaluated using a reductive system with zero-valent iron, and the reductive process coupled with Fenton's reagent. The concentration of the individual target compounds reached up to 400 mg L-1 in the sample. Marked reductions in the chlorinated compounds were observed in the reductive process. The degradation followed pseudo-first-order kinetics in terms of the contaminant and was dependent on the samp (mais) le contact time with the solid reducing agent. An oxidative test with Fenton's reagent, followed by the reductive assay, showed that tetrachloroethylene was further reduced up to three times the initial concentration. The destruction of chloroform, however, demands an additional treatment.
1999-09-01
Resumo em inglês 210Po concentrations have been determined in one green alga and in five freshwater plants grown in a pond of the Carapebus restinga (State of Rio de Janeiro). The alga Chara sp showed elevated concentration of 210Po, similar to that observed for marine algae. All the other plants had the lowest concentration of 210Po in the stems and the highest in the roots. Intermediate values were observed in the leaves. The unexpected high concentration of 210Po in the roots, even sup (mais) erior to reported values for roots of plants from high radioactive background areas, must be due to the elevated levels of this radionuclide in associated soils that are known to be rich in humic organic material. There seem to have been no translocation of this radionuclide from the roots to the other parts of the plants.
2009-01-01
Resumo em inglês Herein, we report the concentration of ethyl carbamate (EC) and copper in 380 samples of sugar-cane spirit and 45 samples of manioc spirit as determined by GC-MS and FAAS respectively. The cyanide content determined spectrophotometrically is reported for the manioc spirit. Sugar cane spirit produced by alembic distillation (70,0 µg L-1) shown a lower content of EC than samples produced by column distillation (270 µg L-1). No simple correlation between the content of EC (mais) and copper for sugar cane spirit as well among the concentration of EC, copper, and cyanide for manioc spirit could be observed.
2007-08-01
Resumo em português Avanços na adubação nitrogenada em cobertura em milho poderão ser obtidos com a inclusão de características de solo como indicadores complementares da disponibilidade de N. Os objetivos deste estudo foram avaliar o potencial de uso, o nível crítico e o melhor estádio de desenvolvimento da cultura para determinação do teor de N-NO3- no solo, visando à predição da disponibilidade de N ao milho, e verificar se a determinação do teor de N-NH4+, em adição ao (mais) teor de N-NO3-, aumenta a eficiência na avaliação da disponibilidade de N. Para isso, realizou-se um experimento por dois anos agrícolas (2002/03 e 2003/04) em Argissolo Vermelho da Depressão Central do RS, no qual se realizou a simulação de diferentes níveis de disponibilidade de N no solo a partir da utilização de cinco doses de N (0, 50, 100, 200 e 300 kg ha-1), parte na semeadura (20 %) e o restante em cobertura (estádio V3). O experimento seguiu o delineamento de blocos casualizados, com quatro repetições, e nos dois anos agrícolas foram avaliados os teores de N-NO3-, de N-NH4+ e de N mineral (N-NO3- + N-NH4+) no solo (0-30 cm), em diferentes estádios de desenvolvimento (V3, V6, V10 e espigamento), e o rendimento de grãos do milho. Em geral, os teores de N-NO3- no solo foram sensíveis às doses de N aplicadas, com destaque para o estádio V6, no qual se verificou também a melhor relação desse elemento com o rendimento de grãos do milho. O nível crítico de N-NO3- no solo, a partir do qual a resposta à aplicação de N é improvável, foi estimado em 20 mg kg-1 para o solo estudado. A avaliação do teor de N-NH4+ do solo, em adição ao teor de N-NO3-, melhorou a predição da disponibilidade de N do solo, como evidenciado pela maior relação deste indicador com o rendimento de grãos, destacando a necessidade de desenvolvimento de kits de determinação rápida do teor de N mineral (N-NO3- + N-NH4+) no solo. Os resultados do uso de N-NO3- e N-NH4+ como indicadores complementares da disponibilidade de N do solo para o milho são promissores, e estudos deverão ser desenvolvidos em diferentes condições edafoclimáticas para confirmar a adequação de seu uso no manejo da adubação nitrogenada em cobertura no milho. Resumo em inglês Nitrogen fertilization applied as sidedressing in corn can be optimized by considering additional soil characteristics as complementary indicators of soil N availability. The objectives of this study were to evaluate the potential use, critical level and best sampling time of the soil nitrate (NO3--N) concentration to predict soil N availability in corn, as well as to verify if the determination of the soil ammonium (NH4+-N) concentration, in addition to NO3--N concentrat (mais) ion, enhances the efficiency of N availability evaluation. A field experiment was conducted in two growing seasons (2002/03 and 2003/04) in Eldorado do Sul, state of Rio Grande do Sul, Brazil. Different levels of soil N availability were simulated by the application of five N rates (0, 50, 100, 200, and 300 kg ha-1) 20 % at sowing and the rest sidedressed at V3. The experiment was structured in a randomized block design with four replications. NO3--N, NH4+-N and soil mineral N (NO3--N + NH4+-N) concentrations in the 0-30 cm soil layer at V3, V6, V10 and at silking, as well as corn grain yield were evaluated in both growing seasons. In general, NO3--N soil concentrations were sensitive to the applied N rates, mainly in V6 when the best relationship between NO3--N and corn grain yield was found. The critical level of soil NO3--N concentration, above which a response to N application is unlikely, was estimated at 20 mg kg-1 in the studied soil, at growth stage V6. The determination of soil NH4+-N concentration, in addition to soil NO3--N concentration, improved the prediction of N availability. A better relationship of soil mineral N (NH4+-N + NO3--N) than of NO3--N concentration with corn grain yield was observed. These results indicate that the development of kits for instant determination of soil mineral N concentration is necessary. NO3--N and NH4+-N as complementary indicators of soil N availability for corn appear promising and studies should be developed under different climate and soil conditions to adequate their use to the management of sidedressed N in corn.
2008-01-01
Resumo em inglês The aim of this work was to study the influence of green tea consumption on fluoride ingestion. The extraction conditions of fluorides from green tea infusions were defined and nine brands of green tea available in Portugal were analyzed. The quantification of fluorides in the green tea was preceded by the implementation and validation of the potentiometric method (commercial fluoride selective electrode). The concentration of fluorides in the samples ranged from 0. 8 to 2. 0 mg L-1.
2002-11-01
Resumo em inglês The surface activity of humic acids (HA) is a parameter which might be considered in the evaluation of all types of aggregation of these substances. In this work the surface tension of aquatic and terrestrial-HA aqueous solutions was observed under varied conditions of pH, concentration and ionic strength. Results showed that HA present surface activity for a extent range of concentration. The surface tension decreases with HA concentration increasing and, for all samples (mais) exist a concentration value above which a reduction in the rate of the solute migration to the solution surface is observed. This value is sensibly reduced and sharpened with the increasing of the ionic strength. Surface tension is also reduced with the acidity increasing, being a minimum reached between pH 3 and 5. Observed effects are explained in view of conformational arrangements of HA which tend to agglomerate in micelle-like domains in aqueous solutions.
2008-12-01
Resumo em português Um experimento foi conduzido para avaliação de uma pastagem de capim-gordura (Melinis minutiflora, Beauv.) degradada, renovada por meio da introdução de capim-braquiária (Brachiaria decumbens, Stapf) em consórcio com estilosantes (Stylosanthes guianensis, cv. Mineirão) e da adubação com nitrogênio (0, 50, 100 e 150 kg/ha.ano). O delineamento experimental foi de blocos ao acaso com três repetições. A pastagem foi avaliada em um período seco com um único cort (mais) e e em um período chuvoso com três cortes. A adubação nitrogenada aumentou a produção de massa seca (MS) e o teor de proteína bruta (PB) do capim-braquiária, tanto no período seco quanto no chuvoso. Os teores de fibra em detergente neutro (FDN) e de fibra em detergente ácido (FDA) não foram influenciados pelas doses de nitrogênio em nenhum dos períodos avaliados. Nas maiores doses de nitrogênio, os teores de fósforo, cálcio e magnésio não se alteraram no período seco nem no chuvoso, enquanto os teores de potássio diminuíram em ambos os períodos. A produção de MS no consórcio de capim-braquiária com o estilosantes foi similar à obtida com o capim-braquiária sem adubação nitrogenada no período seco e não diferiu estatisticamente da produção observada com adubação nitrogenada no período chuvoso. Em geral, o teor de proteína bruta da forragem do consórcio foi maior que o da gramínea pura adubada com nitrogênio. Resumo em inglês An experiment was carried out to evaluate the reclamation of a degraded pasture of molassesgrass (Melinis minutiflora, Beauv.), with the establishment of signalgrass (Brachiaria decumbens, Stapf), with different N doses (0, 50, 100, and 150 kg/ha.year) or in consortium with S. guianensis cv. mineirão, in a complete randomized blocks design, with three replications per treatment. Evaluations were performed during the dry season (one evaluation) and wet season (three evalu (mais) ations). Nitrogen fertilization promoted increment in dry matter production and crude protein (CP) concentration of signalgrass, in both seasons. There were no effect of neutral detergent fiber and acid detergent fiber concentration of signalgrass in both seasons. Increasing N doses did not alter P, Ca, and Mg concentration neither in the dry nor in the rainy seasons, but it decreased K concentration in both seasons. Signalgrass and Stylosanthes mixture presented low dry matter production in the dry season, being similar to signalgrass without nitrogen fertilizer. During the wet season, however there was no statistical difference between the consortium and treatments with nitrogen fertilization. The consortium, in general, presented greater forage CP concentration compared to signalgrass fertilized with nitrogen.
2009-01-01
Resumo em inglês The metal ions removal on cashew bagasse, a low-cost material, has been studied by batch adsorption. The parameters chemical treatment, particle size, biosorbent concentration, and initial pH were studied. In this study the maximum ions removal was obtained on the cashew bagasse treated with 0.1 mol/L NaOH/3 h, at optimum particle size (20-59 mesh), biosorbent concentration (50 g/L) and initial solution pH 5. The kinetic study indicated that the adsorption metal follows p (mais) seudo-second order model for a multielementary system and equilibrium time was achieved in 60 min for all metal ions.
2007-02-01
Resumo em inglês A method for HPLC determination of sulfadimethoxyne in milk is presented. The analyte isolation and concentration were performed by solid-phase extraction through a C-8 cartridge, pre-conditioned with hexane, methanol and water and eluted with MeOH. The recovery determination was done with a spiked solution of 20, 50 or 100 µg L-1. In this concentration range, the recovery was 83.2% with a RDS of 15.4%. For quantification, a Zorbax Eclipse XDB-C8 (4.6 mm x 150 mm, 5 µm), a mobile phase of MeCN: 0.01 mol L-1 KH2PO4 aq. (1:4), and a variable wavelength detector (275 nm) were used.
2006-06-01
Resumo em inglês The serum protein concentration of newborn Holstein calves determined by means of sodium dodecyl sulphate-polyacrylamide (SDS-PAGE) was studied. Blood samples from 40 healthy newborn calves were obtained 48 hours after birth. Calves had been given 3 liters of colostrum within 2 hours after birth, following by dose corresponding by 15% of animal weight each 24 hours. The results showed three different proteinograms: 19 calves had 14 proteins with molecular weights (MW) ran (mais) ging from 28,000 D to 170,000D (proteinogram 1); 11 calves had 14 proteins with MW ranging from 18,000 to 170,000 D (proteinogram 1); and 10 calves had 12 proteins with MW ranging from 28,000 D to 170,000 D (proteinogram 3). The three groups presented similar IgG levels. The highest serum concentration of ceruloplasmin were verified in proteinogram 3, which had the lowest serum level of protein with MW 58,000D. It was verified a1-antitrypsin only in proteinogram 2, which had no proteins with MW of 42,000 D and 37,000D. The highest serum concentrations of IgA and protein with MW 58,000 D, and the lowest serum levels of transferrin, haptoglobin, and acid glycoprotein were verified in proteinogram 3. Measurement of serum protein concentrations by SDS-PAGE may be useful in monitoring the occurrence of hypogammaglobulinemia and the neonatal disease in calves.
2002-05-01
Resumo em inglês Fluoride concentration was determined in rainwater, ground water and soil in the zone of fertilizer industry in the city of Rio Grande. In contaminated rainwater fluorine concentration was registered up to the value of 4,4 mg.L-1. Fluorine concentration in the shallow ground water in general reflects its distribution in the atmosphere, but cannot be used as marker of atmosphere contamination in the urban area due to dissolving influence of residential effluents. The 0,01% (mais) HCl extracts from the set of surface soil samples demonstrates fluoride distribution in the zone of influence of industrial emissions, which coincides to the numerical simulation of fluorides dispersion in the air.
2009-01-01
Resumo em inglês Acid mine drainage generated from coal mine showed a pH of 3.2, high concentrations of SO4(2-), Al, Fe, Mn, Zn and minor As, Cd, Co, Cr, Cu, Ni and Pb. The major reduction in the concentration occurred for Al, As, Cr, Fe and Pb after the treatment with CaO. The evolution of these acid waters within the tributary stream showed decreasing concentration for all soluble constituents, except Al. This natural attenuation was controlled by pH (6.4 to 10.8) as a result of concurr (mais) ent mixing with tributary stream and reaction with local bedrock that contains limestone. Aluminum increasing concentration during this evolution seems to be related to an input of Al-enriched waters due to the leaching of silicate minerals in alkaline conditions.
2008-01-01
Resumo em inglês Anthocyanins are among the most important plant pigments. Due to their potential benefits for human health, there is considerable interest in these natural pigments. Nonetheless, there is great difficulty in finding a technique that could provide the identification of structurally similar compounds and estimate the number and concentration of the species present. A lot of techniques have been tried to find the best methodology to extract information from these systems. In (mais) this paper, a review of the most important procedures is given, from the extraction to the identification of anthocyanins in natural extracts.
2009-06-01
Resumo em inglês This article examines the political determinants of privatization of the fixed telephony sector in four countries, based on a neo-institutionalist approach. These countries faced similar pressures by telephone companies in favor of privatization, suggesting an apparent convergence in the sector's reorganization. However, although all four adopted some degree of privatization, the process followed different paths and designs in each country. This variation can be explained (mais) by the different institutional contexts in which the reforms were carried out. Where there was concentration of power in the Executive, privatization was launched "earlier" and approved more quickly than in countries in which such concentration waslessintense. Meanwhile, the existence of multiple veto points and stakeholders with veto power did not impede the reform, but increased the cost of its unilateral adoption by the Executive, forcing the latter to negotiate and form a minimum consensus within the governing coalition.
2008-01-01
Resumo em inglês Physicochemical constraints severely limit the number of molecules that can be considered as candidates for transdermal delivery. Iontophoresis is a non-invasive technique in which a weak electric current is used to enhance the penetration of molecules into or through the skin. In this review the underlying mechanisms that drive iontophoresis and the impact of key experimental parameters - namely, formulation, drug concentration and pH - on iontophoretic delivery efficiency are discussed. In the final section some devices that are currently commercialized are also described.
2010-01-01
Resumo em inglês Cellulose acetate polymeric membranes had been prepared by a procedure of two steps, combining the method of phase inversion and the technique of hydrolysis-deposition. The first step was the preparation of the membrane, and together was organomodified with tetraethylortosilicate and 3-aminopropyltrietoxysilane. Parameters that exert influence in the complexation of the metallic ion, as pH, time of complexation, metal concentration, had been studied in laboratory using te (mais) sts of metal removal. The membranes had presented resistance mechanics and reactivity to cations, being able to be an alternative for the removal, daily pay-concentration or in the study of the lability of metals complexed.
Portuguese media : new forms of concentration
Comunicação apresentada na Secção de Economia Política da Conferência Científica da International Association for Mass Communication Research (IAMCR), Seul, Coreia do Sul, 3-8 de Julho de 1994. In this paper we will argue that if the Portuguese case is to be fully understood, economic arguments are f...
2005-10-01
Resumo em português Avaliou-se o estresse pós-operatório, durante sete dias, em 30 cadelas, aleatoriamente distribuídas em dois grupos de 15 animais submetidos à ovário-histerectomia (OVH) pelas abordagens laparoscópica (grupo I) e aberta (grupo II). Os grupos foram comparados mediante dosagens do cortisol plasmático. Não se observou aumento do cortisol plasmático no pré-operatório imediato (tempo 1) e quando o animal estava sob anestesia geral imediatamente antes do procedimento (mais) cirúrgico (tempo 2). Nos dois grupos houve aumento do cortisol apenas no período intra-operatório (tempo 3) e uma hora após o retorno anestésico (tempo 4), sendo maior nas cadelas submetidas à OVH por laparoscopia. No pós-operatório, os níveis de cortisol das cadelas de ambos os grupos apresentaram-se normais e equivalentes aos do pré-operatório. Independente da abordagem utilizada, a resposta ao estresse foi semelhante para os dois grupos. Resumo em inglês Post-operative stress, as indicated by changes in plasma cortisol concentration, was monitored for seven days in 30 bitches, half of whom were subjected to conventional (group I) and half to laparoscopic ovariohysterectomy (group II). No increases on plasmatic cortisol concentration were observed in the pre-surgery phase (time 1) and when animals were under anaesthesia just before surgery (time 2). Cortisol concentration increased in both groups only during the intra-oper (mais) ative period (time 3) and one hour after recovery from anesthesia (time 4). Cortisol levels were higher in the bitches submitted to laparoscopy than in those experiencing conventional surgery. For both surgical approaches, cortisol concentrations in the post-operative phase returned to values characteristic of the pre-operative phase. Response to stress, assessed from changes in plasma cortisol concentration, was similar for both groups.
2009-01-01
Resumo em inglês The enzymatic modification of proteins has been widely studied with the aim of add value to low commercial value fish. The objective of this work was to evaluate and optimize the parameters involved in the production process of an enzymatic protein hydrolyzed with high protein content. The results showed that for Alcalase the most significant parameters were temperature, pH and substrate concentration and for Flavourzyme were pH, substrate concentration and enzyme concent (mais) ration. It was obtained for Alcalase a predictive model for the recovered nitrogen and for Flavourzyme a predictive model for the hydrolysis degree.
2008-01-01
Resumo em inglês The objective of this work was to optimize the derivatization reaction for determining deoxynivalenol (DON) by gas chromatography employing an experimental planning procedure. The factors were: temperature, reaction time, catalyst and trifluoroacetic anhydride concentration. The relative peak areas were used to evaluated the effects. The best conditions for DON derivatization were 200 µL TFAA and 18 mg sodium bicarbonate for 6 min at 74 ºC for 7 to 21 µg of DON. Under these conditions, the detection limit was 1.4 µg of DON.
Ordens não inteiras em cinética química/ Non-integer orders in chemical kinetics
2010-01-01
Resumo em inglês Starting from zero-, first-, and second-order integrated laws for chemical kinetics, some cases are shown which produce fractional orders. Taking the Michaelis-Menten mechanism as a first example, it is shown that substrate order can go from 1 to zero, depending on relative concentration of enzyme and substrate. Using other examples which show fractional orders higher than one and even negative (inhibition), it is shown that the presence of an equilibrium before or parall (mais) el to the rate determining step can be the reason for fractional orders, which is an indication of a more complex mechanism.
2002-05-01
Resumo em inglês This paper supplies a compact revision about the main extraction, clean-up and pre-concentration methods of the herbicide glyphosate for water and soil samples, as well as methods for its determination and quantification.
2008-01-01
Resumo em inglês In this work, a new adsorbent was prepared by microencapsulation of sulfoxine into chitosan microspheres by the spray drying technique. The new adsorbent was characterized by Raman spectroscopy, scanning electron microscopy and microanalysis of energy dispersive X-rays. The Cu(II) adsorption was studied as a function of pH, time and concentration. The optimum pH was found to be 6.0. The kinetic and equilibrium data showed that the adsorption process followed the pseudo se (mais) cond-order kinetic model and the Langmuir isotherm model over the entire concentration range. An increase of 8.0% in the maximum adsorption capacity of the adsorbent (53.8 mg g-1) was observed as compared to chitosan glutaraldehyde cross-linked microspheres.
Mathematical modelling of salt water intrusion in a Northern Portuguese estuary
Salinity intrusion is a key issue for estuarine water quality management. Aquatic ecosystem sustainability is highly dependent on salinity concentration dynamics and must be studied for each particular environment. Salinity intrusion into the estuary of the river Lima, in the north-western region of...
Isolation and functional characterization of a biosurfactant produced by Lactobacillus paracasei
In this study, the crude biosurfactant produced by a Lactobacillus paracasei strain isolated in a Portuguesedairy industry was characterized. The minimum surface tension (41.8mN/m) and the critical micelleconcentration (2.5 mg/ml) obtained were found to be similar to the values previously reported...
2007-04-01
Resumo em inglês Natural or modified chondroitin sulfate was incorporated in to polymethacrylate to obtain isolated films. The addition of polysaccharide to synthetic polymers occurred at different rates. Isolated films were micro and macroscopically characterized and swelling index and water vapor transmission were determined. Results indicated changed transparency and flexibility, coupled to their dependence on increase in polysaccharide concentration. A similar occurrence was reported (mais) in the permeability to water vapor and swelling degree. Films composed of modified chondroitin sulfate, 90:10 concentration, showed hydration levels, permeability and morphological properties which allow them to be applied as excipients in the development of new drug delivery systems.
2009-01-01
Resumo em inglês To study the action of Alcalase and Flavourzyme on the proteins of chicken meat, the influence of the substrate concentration [S], enzyme concentration [E] and hydrolysis time on the degree of hydrolysis (DH) of the proteins was evaluated. The highest DH for breast meat was obtained with a [S] of 3.3% (w/v), with a [E] of 6% (w/w) and reaction time of 90 min, for both enzymes. For thigh meat the conditions to get the highest DH were: [S] of 5% (w/v), [E] of 8% (w/w) and a reaction time of 120 min, for both enzymes.
2004-10-01
Resumo em inglês This study presents the bactericidal activity of titanium dioxide photocatalysis, using as model Escherichia coli and Pseudomonas sp. cells. It was observed that the process efficiency is related to initial cell concentration, light intensity, UV irradiation exposure time, TiO2 concentration increase. The ultimate removal efficiency was above 99.9%.
Immigrants at new destinations: How they fare and why
Using matched employer-employee data, we identify the determinants of immigrants' earnings in the Portuguese labor market. Results previously reported for countries with a long tradition of hosting migrants are also valid in a new destination country. Two-thirds of the gap is attributable to match-s...
2009-01-01
Resumo em inglês Secondary alcohol concentrations in sugar cane spirits from different origins were determined by gas chromatography. A great variation in the concentration of the secondary alcohols was found in these spirits. Of the 33 brands analyzed, 8 of them were found to be out of conformity with the legislation. Sec butanol, for which the maximum allowed concentration level is 100 mg.L-1 in absolute ethanol, was found within a concentration range between 5 mg.L-1, the limit of quan (mais) titation (LQ) and 408 mg.L-1 in absolute ethanol. Sugar cane samples from Salinas, MG, were the only ones that exhibited self similarity because of the low concentrations of n-butanol and n-amylic alcohol (
2007-04-01
Resumo em português Esta pesquisa foi realizada visando avaliar a qualidade do volumoso produzido com a técnica de hidroponia. Como substratos, utilizaram-se casca de arroz e capim-elefante picado cultivado sobre lona plástica, com densidade de 2,5 kg de grãos/m². Os dados foram analisados em delineamento inteiramente casualizado, com sete repetições, representadas por canteiros de 0,5 x 0,5 m de área útil. A fertiirrigação foi usada do 3º ao 14º dia após a semeadura, quando foi (mais) realizada a colheita para determinação da produtividade da forragem natural/m², da porcentagem de MS total e dos teores de PB, FDN, FDA e cinzas. Essas características foram determinadas em amostras da forragem completa, do substrato + raízes e em amostras apenas das plantas. O uso de casca de arroz como substrato resultou em maior produção de MS, FDN, FDA e cinzas. O capim-elefante destacou-se pelo maior teor de PB, mesmo que com baixo teor de MS. A PB apresentou relação inversa com MS, FDN, FDA e cinzas. Resumo em inglês This research was carried out to evaluate the quality of the roughage produced by hydroponics. Rice hulls and chopped elephantgrass were used as substrates for corn cultivation, put on plastic canvas. Corn seeding density was 2.5 kg of seed/m². A randomized experimental design was used, with seven replications. Plot utile area measured 0.5 m x 0.5 m. Fertiirrigation was used from the 3rd to the 14th day after seeding. Harvest occurred at the 14th day and fresh forage pro (mais) ductivity was determined. Three types of samples were taken: complete forage (shoot + root + substratum), substratum + roots, and shoot only. The following response variables were determined: DM concentration, CP, NDF, ADF, and ash. The rice hulls substratum resulted in higher DM production, NDF, ADF and ash concentration, while the chopped elephantgrass promoted greater CP concentration, although with low DM concentration. The CP presented inverse relationship with DM concentration and its components: NDF, ADF and ash.
2008-01-01
Resumo em inglês Mixed-micelle formation between sodium chlolate (NaC) and the anionic surfactant sodium dodecanoate (SDoD) in Tris-HCl buffer solutions, pH 9.00, varying the molar fraction of the surfactants, was investigated by means of electrical conductivity and steady-state fluorescence of pyrene. The critical micelar concentration (cmc) was measured from the equivalent conductance versus the square root of the molar surfactant concentration plots and the regular solution theory (RST (mais) ) was used to predict the mixing behavior. The I1/I3 pyrene ratio-surfactant concentration plots were used as an additional technique to follow the behavior and the changes in the micropolarity of the mixed micelles.
Fibrates but not statins increase plasma selenium in dyslipidemic aged patients - The EVA study
This secondary analysis of "Etude du Vieillissement Arteriel" (EVA) study reports the effect of fibrates and statins on plasma selenium concentration and its 9-year change in free-living dyslipidemic elderly. Dyslipidemic patients were categorized in three sub-groups according to final low-density l...
2005-06-01
Resumo em inglês In this work, the feasibility of employing micelle-mediated extraction for selective separation of homologous or isomeric organic compounds is demonstrated. Firstly, the main parameters controlling extraction performances, such as surfactant concentration and temperature were varied. A Scheffé-type experimental design was demonstrated as a novel and useful method to characterize the various experimental factors. At each point selected in the two-phase domain and for a gi (mais) ven solute, extraction percentage (E%), concentration ratio, phase volume ratio, and equilibrium partition coefficient (K C) were determined. The values of E% and K C decrease in the following order: phenol > 1-phenylethanol ~ 2-phenylethanol > benzyl alcohol.
2008-01-01
Resumo em inglês This work presents a study on the separation of Fe(III) and Ti(IV) from sulfuric acid leaching solutions of ilmenite (FeTiO3) using liquid-liquid extraction with D2EHPA in n-dodecane as extracting agent. The distribution coefficients (K D) of the elements related to free acidity and concentration of Fe(III) and Ti(IV) were determined. Free acidity was changed from 3x10-2 to 11.88 mol L-1 and D2EHPA concentration was fixed at 1.5 mol L-1. Recovery of final products as well (mais) as recycling of wastes generated in the process were also investigated. The LLE process as a feasible alternative to obtain high-purity TiO2.
2008-01-01
Resumo em inglês Phosphates have been used for lead immobilization in soils but the influence of soil type is not fully understood. In this work, lead chemical behaviour in two Brazilian latosoils (LA and LV) was studied via treatment with phosphates. The Pb concentration in Toxicity Characteristic Leaching Procedure (TCLP) solutions was decreased in all treatments. After treatment with H3PO4 the Pb concentration in the LA remained within the regulatory limit established by EPA. The ecoto (mais) xicological results with Daphnia pulex showed that this treatment reduced the lead bioavailability. Sequential extraction analyses showed that the lead was transferred from the most available to the residual fraction. Relevant decrease of soluble lead was observed in all phosphate treatments.
2007-02-01
Resumo em inglês In this work commercial filters papers were organomodified with tetraethylorthosilicate (TEOS) and 3-aminopropyltriethoxysilane (3-APTS), aiming at the development of a new analytical procedure for in-situ speciation of labile and inert metal species in aquatic systems. Parameters that exert influence on the metal lability such as pH, chelating time, concentration and characteristics of the organic matter were studied in the laboratory using tests for metal recuperation. (mais) The results showed slower kinetics for Cu ion than for Ni, Mn and Cd in the absence of aquatic humic substances (AHS). The relative lability observed for complexed metals in aquatic humic substances using organomodified filter papers was Cu>>Cd>Ni>Mn. The pH values, structural characteristics and concentration of AHS exert strong influence on the lability of the metals. The results obtained showed that the utilization of organomodified filter papers can be an interesting and promising alternative for in situ characterization of metal lability in aquatic systems.
2011-01-01
Resumo em inglês The history of sewage contamination in the Mundaú-Manguaba estuarine lagoon system (NE Brazilian coastal zone) was evaluated through the concentration of sterols in sediment cores. The concentration of coprostanol increased towards the surface sediments, with the maximum of 5.65 µg g-1 at 0-2 cm sediment layer in Mundaú. Manguaba exhibited a lower level of contamination. The ratio cholestanol/cholesterol suggested degradation of coprostanol only before the burial of or (mais) ganic matter in the sediment. This feature, together with information of population growth in the watershed, allowed the estimation of a sedimentation rate of 0.90 cm year-1 to the Mundaú lagoon.
2010-01-01
Resumo em inglês Biogenic silica is used to describe compounds of hydrated silica (SiO2.nH2O), with specific shapes and sizes, deposited in plants. The chemical composition of biogenic silica and its stability in Jaraguá grass was studied in increasing concentration of NaOH. The analytical results demonstrated high concentration of Si, Al, Fe, Mg, P and low of Cu, Cd and Zn in the phytoliths composition. The silica bodies stability in NaOH solution with increasing concentration was diffe (mais) rent among the shapes and sizes. Silicified stomata and silicified plant tissues were dissolved along with the dumbbells because they are the less stable forms of biogenic silica.
2008-01-01
Resumo em inglês Determination of Cr(VI) and Cr(III) was studied in soil samples accidentally contaminated with sulphochromic solution. Molecular absorption spectrophotometry based on the diphenylcarbazide method was used for the determination of Cr(VI) after its alkaline extraction. The total chromium concentration was determined using ICP OES. The quantification of Cr(III) was accomplished by subtracting the Cr(VI) concentration from the total chromium concentration. Regardless of the k (mais) nown contamination of the soil samples by sulphochromic solution, concentrations of Cr(VI) were below the detection limit. Addition and recovery experiments for Cr(VI) in soil samples with and without organic matter indicated its influence on the reduction of Cr(VI) to Cr(III).
2009-01-01
Resumo em inglês A method for determination of Cr(III) and Cr(VI) in cement and cement-related materials was studied. Molecular absorption spectrophotometry based on 1,5-diphenylcarbazide as chromogenic reagent was used for determination of Cr(VI) after alkaline extraction. The total chromium concentration was determined using flame atomic absorption spectrometry (FAAS) after complete sample decomposition by fusion. The quantification of Cr(III) was accomplished by subtracting the Cr(VI) (mais) concentration from the total chromium concentration. The concentration of Cr(III) in the samples ranged from 10.9 to 88.0 mg kg-1, whereas only in few samples the Cr(VI) concentration was higher than the value established by the European Community to this type of sample [2 mg kg-1 Cr(VI)].
2007-01-01
Resumo em inglês The plating process generates solid waste rich in heavy metals and aiming to reduce environmental impact of such waste, this work suggests a methodology for zinc reduction, through a 2(4) factorial planning, studying the influence of the following variables: acid concentration (15, 20 or 30% v/v), acid type (sulfuric or hydrochloric), acid volume (15, 20 or 25 mL) and extraction time (12, 24 or 36 h). Through this methodology it is possible to establish the optimal conditions (15 mL of a 30% hydrochloric acid concentration during 12 h) to get a 100% efficiency in zinc extraction.
2003-08-01
Resumo em inglês In this work two procedures were proposed for analytical curves construction using a single standard solution employing a flow injection system with solid phase spectrophotometric detection (FI-SPS). A flow cell contends the chromogenic reagent 1-(2-tiazolylazo)-2-naphtol was positioned on the optical path. The first procedure was based on controlled concentration of analyte on solid phase and the relations between absorbance and the total volume of injected allowed the c (mais) alculation of analyte concentration. The second procedure was developed employing controlled dispersion/retention in flow system where analyte concentration was obtained by exploiting the relation between transient signals of samples and single standard solution at equivalent reading time. The procedures were successfully applied for zinc determination in synthetic solutions with good precision and accuracy at 95% confidence level.
2009-01-01
Resumo em inglês An enzymatic method was used for obtaining protein extracts from wheat flour using an alkaline protease. Some parameters were evaluated aiming the optimization of this method: temperature (40-50 ºC); time (2-5 h); physical treatment of the sample (no treatment, ultra-turrax/16,000 rpm/5 min and ultrasound/120 W/10 min); enzyme:substrate ratio (E:S) of 5:100 - 10:100 and concentration of wheat flour (1:3, 1:5 and 1:10 w/v). The results showed that the best condition for p (mais) rotein extraction was that using the sample concentration of 1:3 (w/v), ultra-turrax, E:S of 10:100, at 40 ºC, 2 h, having reached an extraction yield of 88.53%.
2010-06-01
Resumo em português Avaliou-se o efeito da adição de diferentes fontes de óleo e níveis de suplementação de vitamina E na ração sobre as características do sêmen in natura de suínos reprodutores. Foram utilizados 24 reprodutores Dalboar 85, com idades entre 12 e 18 meses, distribuídos em delineamento inteiramente ao acaso, em arranjo fatorial 2 x 3, com duas fontes de óleo, soja e salmão, e três níveis de antioxidantes, 150, 300 e 450mg de vitamina E/kg. Volume, motilidade es (mais) permática total, teste hiposmótico, porcentagem de espermatozoides vivos e morfologia espermática não diferiram (P>0,05) entre os tratamentos. Óleo de salmão (P Resumo em inglês The addition of oil sources and dietary vitamin E supplementation was evaluated on the characteristics of fresh boar sperm. Twenty-four mature Dalboar 85 boars of proven fertility and in routine semen production for artificial insemination were randomly distributed in a factorial arrangement 2 X 3, with two oil sources, soy and salmon, and three antioxidant levels: 150, 300, and 450mg/kg of vitamin E. Volume, total motile sperm, hyposmotic swelling test, percentage of liv (mais) e cell, and morphology did not differ (P
2007-12-01
Resumo em português Esta pesquisa foi desenvolvida com o objetivo de avaliar o efeito da adubação nitrogenada (100, 200, 300, 400 kg/ha/ano de N) e da irrigação (área irrigada - AI e não-irrigada - ANI) sobre a composição quimico-bromatológica da planta inteira (PI) (colmo+folha) e das lâminas foliares dos perfilhos basais não-decapitados (LF-PBNd) e decapitados (LF-PBd) do capim-elefante cv. Napier. Adotou-se delineamento experimental em blocos casualizados com três repetições (mais) , em que a unidade experimental consistiu de parcelas (piquetes de 300 m²), nas quais foram aplicados os tratamentos. Os teores de PB apresentaram valores proporcionais às doses de nitrogênio, observando-se os maiores valores, no período das águas, nas LF-PBNd e LF-PBd. Os resíduos das doses N aplicados no período chuvoso tanto na AI como ANI elevaram os teores de PB nas lâminas foliares das duas categorias de perfilhos, mas não sobre os teores de FDN e FDA. A irrigação proporcionou teores de FDN e FDA mais elevados nas LF-PBNd e LF-PBd e menores na planta inteira, porém, não se observou efeito sobre os teores de PB. Resumo em inglês This research was carried out to evaluate the chemical composition of elephantgrass cv. Napier in the whole plant (WP) (stem+leaf) and in the leaf blade of non-decapitated basal tillers (SF-NDBT) and leaf blade of decapitated basal tillers (SF-DBT), fertilized with different N doses (100, 200, 300, and 400 kg/ha/year of N) in an irrigated area (IA) and in a non-irrigated area (NIA). Treatments were analyzed in a randomized block design with three replicates. The CP concen (mais) trations were proportional to the N doses with greater CP concentration in the rainy season in fractions SF-NDBT and SF-DBT. Fertilizer residues of N doses applied in the rainy season, both in IA and NIA, increased CP concentration in the leaf blade of the two tiller categories, but did not affect NDF and ADF concentration. Irrigation increased concentration of NDF and ADF in SF-NDBT and SF-DBT and reduced it in the WP, with no effect on CP concentration.
Dominação demográfica no contexto do século XX português: Lisboa, a capital
Ao longo do século XX Lisboa esmaga, do ponto de vista demográfico, os outros centros urbanos e domina sem competição o país. Primeiro sozinha, crescendo violentamente face a um Portugal Continental contido no seu crescimento populacional. Cresce ao ponto de em 1960 concentrar um número único de hab...
2007-06-01
Resumo em inglês The study assessed selenium concentrations in the muscle tissues and liver samples of three fish species and in the soft tissues of a mussel species. The samples were analyzed by GF-AAS using Zeeman background correction. Selenium in the muscle samples was higher in carnivorous fish. The liver of all studied fish species presented higher selenium concentrations than the muscle. The fish species presented a high positive correlation between their total length and selenium (mais) concentration. A significant correlation was observed between the selenium concentration in the mussel soft tissues and the condition index.
2007-01-01
Resumo em inglês The electrochemical applications of a CPE modified with chitosan for the determination of Cu(II) in wastewater samples using anodic stripping voltammetry are described. The best voltammetric response was observed for a paste containing 25% m/m of chitosan. A 0.10 mol L-1 NaNO3 solution (pH 6.5) as supporting electrolyte, a pre-concentration potential of -0.20 V, pre-concentration time of 270 s and a scan rate of 25 mV s-1 were selected. The calibration graph was linear in the Cu(II) concentration range from 2.0 x 10-7 to 7.4 x 10-6 mol L-1, with a detection limit of 8.3 x 10-8 mol L-1.
2007-08-01
Resumo em inglês Analytical procedures used for determining the concentrations and isotope composition of strontium in subsurface waters, by mass spectrometry, are described. Sampling was performed in coastal plateaus, salt marsh and mangrove environments in the coastal region of Pará. Coastal plateau waters have delta87Sr between 1.51 and 6.26‰ and Sr concentration bellow 58 ppb. Salt marsh waters show delta87Sr between 0.55 and 0.90‰ and Sr concentration between 93 and 114 ppm, while (mais) mangrove waters have delta87Sr‰ around zero and Sr concentration above 15 ppm. Differences in the 87Sr/86Sr ratio in these subsurface waters are detected, as well as seasonal variations in the coastal pleteau waters.
2010-01-01
Resumo em inglês The tebuconazole photocatalytic degradation kinetics was studied in a batch reactor using TiO2 (P25-Degussa) as catalyst and a high pressure mercury lamp. The photolysis, adsorption and irradiation effects in the reaction rate were evaluated. Afterward, the suspension catalyst concentration and initial pH to the maximum reaction rate was determined. It was observed that the reaction rate can be approached by a pseudo-first order, with a maximum kinetics constant at 260 mg L-1catalyst concentration and pH 7.7.
2008-08-01
Resumo em português Sementes de feijoeiro (Phaseolus vulgaris) com alto teor de molibdênio podem garantir o suprimento adequado desse nutriente para a cultura. Foram realizados dois experimentos em casa de vegetação, com o objetivo de avaliar o efeito de sementes enriquecidas com Mo, obtidas em plantas que receberam adubação foliar, no crescimento e acumulação de N do feijoeiro. O substrato foi horizonte A de Argissolo em vasos de 3,5 kg, que receberam calagem e nutrientes, exceto Mo. (mais) O primeiro experimento teve arranjo fatorial 3 x 2 x 2 com cinco repetições: três cultivares de feijoeiro, duas concentrações de Mo na semente e duas épocas de coleta. Plantas originadas de sementes com alto teor de Mo, dos três cultivares, apresentaram maior acumulação de biomassa e N na parte aérea, nas duas épocas de coleta. Sementes com alto teor de Mo aumentaram a massa de nódulos dos cultivares Manteigão e Rio Tibagi aos 30 dias pós-emergência (DAE), mas reduziram a massa e o número de nódulos dos cultivares Carioca e Manteigão aos 45 DAE. O maior teor de Mo nas sementes aumentou a atividade da nitrogenase aos 30 DAE e a atividade específica da nitrogenase aos 45 DAE. O segundo experimento teve arranjo fatorial 2 x 2 x 4 com cinco repetições: dois cultivares, dois níveis de Mo na semente e quatro épocas de coleta. Plantas oriundas de sementes com alto teor de Mo apresentaram maior massa de parte aérea aos 47 e 59 DAE, e maior acumulação de N na parte aérea aos 59 DAE. O maior teor de Mo nas sementes não afetou a nodulação até os 45 DAE, mas reduziu o número de nódulos aos 59 DAE. A redução na nodulação no estádio de enchimento de vagens observada nos dois experimentos, nas plantas oriundas de sementes com alto teor de Mo, pode ser atribuída ao maior crescimento dessas plantas, que teria antecipado a translocação de assimilados para as vagens. Pode-se concluir que sementes enriquecidas com Mo, colhidas em plantas que receberam adubação foliar, podem estimular a atividade da nitrogenase e aumentar a acumulação de biomassa e N do feijoeiro. Resumo em inglês Common bean (Phaseolus vulgaris) seeds with high molybdenum concentration can adequately supply the crop demand of this nutrient. Two experiments were conducted in a greenhouse to evaluate the effect of Mo-enriched seeds, obtained from plants treated with foliar fertilization, on growth and N accumulation by common bean plants. The soil substrate was the A horizon of a Haplustult (3.5 kg pots), which were limed and fully fertilized with exception of Mo. The first experime (mais) nt had a 3 x 2 x 2 factorial design with five replications: three bean cultivars, two seed Mo concentrations, and two harvest dates. In plants of the three cultivars originating from seeds with high Mo concentration, the shoot biomass and N accumulation were higher at both harvests. Seeds with high Mo concentration increased the nodule mass of cultivars Manteigão and Rio Tibagi 30 days after emergence (DAE) but reduced biomass and number of nodules in the cultivars Carioca and Manteigão 45 DAE. High seed Mo concentration increased the nitrogenase activity 30 DAE and the specific nitrogenase activity 45 DAE. The second experiment had a 2 x 2 x 4 factorial design with five replications: two bean cultivars, two seed Mo concentrations, and four harvest dates. The shoot mass in plants originating from seeds with high Mo concentration was higher 47 and 59 DAE, and shoot N accumulation was higher 59 DAT. High seed Mo concentration did not affect nodulation until 45 DAE, but reduced nodule number 59 DAE. The reduced nodulation at the pod filling stage observed in both experiments, in plants grown from seeds with high Mo concentration, can be due to the improved growth of these plants, which may have anticipated the translocation of assimilates to pods. It can be concluded that Mo-enriched seeds, harvested from plants treated with foliar fertilizer, can stimulate nitrogenase activity and increase biomass and N accumulation in common bean plants.
1999-02-01
Resumo em inglês In order to evaluate the chromium contamination from tannery discharges into rivers in the State of Minas Gerais, samples of water and suspended material were collected and submitted to chemical analysis. The total content of chromium in the samples was measured by flame atomic absorption spectrophotometry. Water samples were analysed by standard addition method, while chromium concentration in suspended materials was determined by calibration curves. Localities investiga (mais) ted were Ipatinga, Matias Barbosa, Dores de Campo, Ressaquinha, Ubá and Juiz de Fora. Samples from a not-industrialized area were also analysed to obtain regional background values. Metal inputs were related to effluent discharges into the rivers. Suspended material transported Cr downriver. Chromium concentration in river water exceeded 656 times the value of the Brazilian Environmental Standards, while its concentration in suspended material ranged from 15 to 11066 µg g-1.
Comparative study between natural and artificial zeolites as supports for biosorption systems
This study aims the definition of a new material that may act as a robust and yet costeffective biosorbent for treatment of wastewater with low concentration of heavy metals. Acomparative study was made between two biosorption systems composed of an Arthrobacterviscosus biofilm supported on Cuban...
Changes in Ochratoxin A concentration during winemaking
The effects of common winemaking procedures on ochratoxin A (OTA) concentrations in the Portuguesewine Vinho Verde were studied. Natural contamination of grapes was not observed, so grapes for vinificationwere inoculated with Aspergillus carbonarius. Ochratoxin A concentration in these grapes rang...
2008-03-01
Resumo em português TEMA: a intoxicação por chumbo pode causar deficiências neuropsicológicas, que incluem a linguagem, devido aos danos provocados no desenvolvimento do SNC. OBJETIVO: verificar a ocorrência de alterações de linguagem em crianças com histórico de intoxicação por chumbo e a correlação entre o índice de chumbo sangüíneo e as alterações de linguagem apresentadas pelas crianças. MÉTODO: avaliação da linguagem de 20 crianças em idade pré-escolar, com índi (mais) ce de chumbo sangüíneo acima de 10 µg/dl. RESULTADOS: 13 crianças apresentaram distúrbio de linguagem envolvendo somente a Fonologia ou mais de um subsistema lingüístico. A análise estatistica revelou não existir correlação entre a gravidade das alterações e os índices de chumbo apresentado. CONCLUSÃO: a ocorrência de crianças com distúrbio de linguagem aponta a contaminação por chumbo como um fator de risco para as alterações apresentadas, mesmo tendo sido encontrados outros fatores que levem à defasagem no desenvolvimento da linguagem e ausência de correlação entre as referidas variavéis. Resumo em inglês BACKGROUND: lead poisoning can have a negative impact on the neuropsychological functions, including language, due to the damage it causes to the development of the Central Nervous System. AIM: to verify the occurrence of language disorders in children who suffered from led poisoning and to verify the correlation between the lead concentration level in the blood and the language disorders presented by the children. METHOD: language evaluation of 20 preschoolers, with lead (mais) concentration level in the blood above 10µg/dl. RESULTS: 13 children presented language impairment involving only phonology or more than one language subsystem. The statistical analysis indicated that no correlation exists between the severity of the language impairment and the concentration levels of lead. CONCLUSION: the number of children with language impairment indicates lead poisoning as a risk factor for the present alterations, even though other risk factors for language disorders were found and the absence of correlation between the investigated variables.
The focus of this work is to explore the use of the netted whelk, Nassarius reticulatus (L.), as an indicator of mercury (Hg) contamination, by assessing the concentration of Hg in the sediments and in the whelk along the entire Portuguese coast. Total Hg concentrations ranged from below the detecti...
2007-06-01
Resumo em inglês The perception of the flavor is an important attribute of quality in marine fish and other seafoods, being the first and main factor of discrimination for the evaluation, later acceptance and preference of the product by the consumer. Recently, the simple bromophenols have been considered an important group of key flavor compounds occurring in a wide variety of seafood species like fishes, mollusks, crustaceans and algae. When present in high concentration, in seafood, th (mais) e bromophenols produce an undesirable flavor and are associated with inferior quality. Meanwhile, when present in low concentration levels (for example ng g-1) these compounds produce a desirable marine - or ocean-like - flavor and enhance the existing flavor in seafood. Indeed, simple bromophenols are widespread in seafood but virtually absent in freshwater fish. Herein we present a review on these flavor components found in the marine environment.
2003-08-01
Resumo em inglês Rainwater samples were analyzed during a one-year period (June 1999 - June 2000) and presented concentration of pH = 4.9 (volume weight mean). The ions concentrations results showed a high sulfate concentration (35 µmol L-1), followed by the cations concentration of sodium, calcium and ammonium (35, 16 and 30 µmol L-1, respectively). Due to the great contribution of these cations in the sulfate neutralization action, the rainwater of this region had only a light acid ch (mais) aracteristic. The soil characteristic was acid and the bioavailable concentration of the alkaline cations (Ca, Mg and K) presented high calcium concentrations (1001 ± 357 mg kg-1) compared with the other cations. The determination of soil sensitivity to acid rain was calculated by the ratio BC/Al3+ (BC = Ca2+ + Mg2+ + K+) and presented the average value of 5.1 ± 3.3. This preliminary evaluation of soil susceptibility by the ratio BC/Al3+ showed that the local soil and vegetation type (tropical Savannah) were sensitive to acid deposition. The long term of this impacting condition (acid rain, high sulfate deposition) could be harmful to the soil and vegetation quality.
2009-01-01
Resumo em inglês The obtained corn germ phytic acid (CGPA) antioxidant potential was evaluated through the deoxyribose, bathophenanthroline (BPS) and DPPH• assays. In the concentration of 130.5 μM of CGPA the hydroxyl radical maximum sequestering antioxidant activity was 29.3% while standard phytic acid (SPA) presented this maximum activity of 18.2% in the concentration of 33.2 μM of SPA. The BPS assays revealed that the chelation activity towards Fe2+ increased concurrently wi (mais) th the increase of CGPA concentration and its Fe2+ contact time. Finally, DPPH• assay showed that CGPA and SPA did not present electron-donating capacity to DPPH•.
2009-01-01
Resumo em inglês Mixtures of ethyl(hydroxyethyl)cellulose (EHEC) and Sodium Dodecyl Sulfate (SDS) were investigated using surface tension, conductivity and viscosity measurements in aqueous solutions. The parameters of the surfactant to polymer association processes such as the critical aggregation concentration (cac) and saturation of the polymer by SDS (psp) were determined from the plots of surface tension and specific conductivity versus surfactant concentration. Through the final res (mais) ults we see that there was no specific link of polymer with the surfactant, implying therefore a phenomenon of only cooperative association.
2008-06-01
Resumo em português O feijão (Phaseolus vulgaris L.) constitui a base alimentar da população brasileira. Muitos fatores determinam a baixa produtividade do feijoeiro, desde problemas políticos até fatores técnicos, dentre eles a adubação e nutrição. O objetivo foi avaliar os atributos químicos do solo e produção do feijoeiro (cv. Pérola) de acordo com a aplicação de calagem e Mn. O experimento foi realizado em vasos com Latossolo Vermelho-Amarelo distrófico típico fase cerr (mais) ado, em delineamento inteiramente casualizado com três repetições, em esquema fatorial 2 x 6, envolvendo duas doses de uma mistura de CaCO3 e MgCO3, na relação molar 3:1 (de calcário, calculadas) para elevar a saturação por base para 50 % e para 70 % e seis doses de Mn (0, 20, 40, 60, 80 e 100 mg dm-3). Na análise dos resultados, verificou-se decréscimo no teor foliar de Mn de acordo com o aumento da saturação por base, não sendo observado o mesmo efeito no solo após o cultivo. O teor de Mn no solo para produção máxima de grãos mostrou-se semelhante para saturação por base de 50 e 70 %; no entanto, a dose do micronutriente aplicada para essa produção foi de 28 mg dm-3 e 57 mg dm-3, respectivamente. Resumo em inglês Common bean is one of the most important staples in Brazil. The objective of this study was to evaluate the common bean cv. Pérola yield and changes in soil chemical attributes as influenced by liming and manganese rates. The experiment was carried out in pots containing dystrophic Red Yellow Latosol (Oxisol). Treatments consisted of a 2 x 6 factorial combination of two limestone (CO3 and MgCO3 in a 3:1 molar ratio) rates, calculated to increase base saturation to 50 and (mais) 70 %, respectively, and six Mn rates (0, 20, 40, 60, 80 and 100 mg kg-1), using MnSO4.H2O as source. There were three repetitions. Results showed that a higher base saturation reduced leaf Mn concentration, but soil Mn concentration after harvest was not altered. The soil Mn concentration sufficient to reach the maximum grain yield was similar for both 50 and 70 % base saturation, but the doses to reach such critical soil concentration were 28 and 57 mg dm-3, respectively.
2008-04-01
Resumo em inglês In vitro activity of the essential oil Origanum vulgare against Sporothrix schenckii was determined by the MIC (Minimum Inhibitory Concentration). For this, seven samples of S. schenckii were studied, two isolated from two cases of human sporotrichosis and five isolated from cats. Analysis of the essential oil was carried out in a gas chromatograph (GC/FID) for the identification and quantification of thymol and carvacrol (antifungal agents). MIC was obtained based on the (mais) microdilution method according to the adapted document NCCLS-M 27A2 for fitopharmacy. All the isolates presented sensibility to the essential oil. S. schenckii was inhibited in a concentration of 0.25% (250m l/ml). Chromatographic analysis showed that thymol concentration was bigger than carvacrol. The antifungal activity demonstrated by the essential oil of O. vulgare against S. Schenckii stimulates the accomplishment of more studies, including in vivo studies.
2010-01-01
Resumo em inglês This work discusses an analytical procedure for analysis of sulfur compounds in treated petroleum refinery gaseous effluents using a sulfur chemiluminescence detector with dual plasma burner (SCD-DP). Calibration was accomplished by using standards and gaseous streams of known concentration of sulfur compounds. The response factors agree with the calibration table of ASTM standard D 5504 (2008). The detection range for sulfur compounds is in μg m-3. The analytical pr (mais) ocedure allowed the construction of a chromatographic chart of sulfur compounds present in several refinery gaseous effluents. SO2 was the most difficult compound to be determined because of its high reactivity.
Anthocyanin Concentration of “Assaria” Pomegranate Fruits During Different Cold Storage Conditions
The concentration of anthocyanins in fruits of “Assaria” pomegranate, a sweet Portuguese cultivar typically grown in Algarve (south Portugal), was monitored during storage under different conditions. The fruits were exposed to cold storage (5°C) after the following treatments: spraying with wax; spr...
Ambiental volatile organic compounds in the megacity of São Paulo
2008-01-01
Resumo em inglês In order to characterize the composition of the main urban air organic compounds in the megacity of Sao Paulo, analysis of samples collected during the winter of 2003 downtown was carried out. The samplings were performed on the roof of a building in the commercial center of São Paulo. Hydrocarbons and carbonyls compounds were collected on August 4, 5 and 6. Comparing to previous data, the concentration of hydrocarbons presented no decrease in the concentration, except f (mais) or the aldehydes, which decreased when compared to previous data. Among the HCs species analyzed, the highest concentrations observed were those of toluene (7.5 ± 3.4 ppbv), n-decane (3.2 ± 2.0 ppbv), benzene (2.7 ± 1.4 ppbv) and 1,3,5-trimethylbenzene (2.2 ± 1.5 ppbv).
2008-04-01
Resumo em português O objetivo do estudo foi analisar a presença de alcoolemia em vítimas fatais de acidentes de trânsito, no Distrito Federal, em 2005. De 442 óbitos, 163 foram resultantes de atropelamentos, 84 de capotagem e 195 de colisão. A alcoolemia foi dosada em 238 casos (53,7%). A maioria das vítimas era jovem, entre 18 e 35 anos e do sexo masculino. Entre as vítimas de colisão, 44,2% tinham níveis de alcoolemia acima de 0,6 g/l; nas vítimas de capotagens, esse percentual (mais) foi de 57,7% e, entre os pedestres, 32,5%. A diferença entre as proporções de vítimas com alcoolemia positiva foi estatisticamente significativa para os que sofreram acidentes de capotagem em relação aos demais. Resumo em inglês The objective of the study was to assess the association between high blood alcohol levels and fatal victims of traffic accidents in the Brazilian Federal District, in 2005. A total of 442 casualties (163 pedestrians, 84 victims of overturns, and 195 of collisions) were studied. Blood alcohol concentration was analyzed in 238 cases (53.7%). Most victims were young males, aged between 18 and 35 years. Blood alcohol levels higher than 0.6 g/L were detected in 44.2% of colli (mais) sion victims; 57.7% of victims of overturns and 32.5% of pedestrians. The difference in proportions between overturn victims with blood alcohol concentration higher than 0.6 g/L and those victims of other traffic accidents was statistically significant.
2008-04-01
Resumo em português O objetivo do estudo foi analisar a presença de alcoolemia em vítimas fatais de acidentes de trânsito, no Distrito Federal, em 2005. De 442 óbitos, 163 foram resultantes de atropelamentos, 84 de capotagem e 195 de colisão. A alcoolemia foi dosada em 238 casos (53,7%). A maioria das vítimas era jovem, entre 18 e 35 anos e do sexo masculino. Entre as vítimas de colisão, 44,2% tinham níveis de alcoolemia acima de 0,6 g/l; nas vítimas de capotagens, esse percentual (mais) foi de 57,7% e, entre os pedestres, 32,5%. A diferença entre as proporções de vítimas com alcoolemia positiva foi estatisticamente significativa para os que sofreram acidentes de capotagem em relação aos demais. Resumo em inglês The objective of the study was to assess the association between high blood alcohol levels and fatal victims of traffic accidents in the Brazilian Federal District, in 2005. A total of 442 casualties (163 pedestrians, 84 victims of overturns, and 195 of collisions) were studied. Blood alcohol concentration was analyzed in 238 cases (53.7%). Most victims were young males, aged between 18 and 35 years. Blood alcohol levels higher than 0.6 g/L were detected in 44.2% of colli (mais) sion victims; 57.7% of victims of overturns and 32.5% of pedestrians. The difference in proportions between overturn victims with blood alcohol concentration higher than 0.6 g/L and those victims of other traffic accidents was statistically significant.
An approach for multiple biomass growth rates and biomass concentration estimation isproposed for a class of bioprocesses characterizing by on-line measurements of dissolved oxygenconcentration and off-line measurements of biomass concentration. The approach is based onadaptive observer theory an...
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