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41.
X. Nogueira I. Colominas L. Cueto-Felgueroso S. Khelladi 《Computer Methods in Applied Mechanics and Engineering》2010,199(23-24):1471-1490
In this work we study the dispersion and dissipation characteristics of a higher-order finite volume method based on Moving Least Squares approximations (FV-MLS), and we analyze the influence of the kernel parameters on the properties of the scheme. Several numerical examples are included. The results clearly show a significant improvement of dispersion and dissipation properties of the numerical method if the third-order FV-MLS scheme is used compared with the second-order one. Moreover, with the explicit fourth-order Runge–Kutta scheme the dispersion error is lower than with the third-order Runge–Kutta scheme, whereas the dissipation error is similar for both time-integration schemes. It is also shown than a CFL number lower than 0.8 is required to avoid an unacceptable dispersion error. 相似文献
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A Alonso F Domínguez M Verez B Rodríguez J Benavente JM Barros J Carreró A Ojea JL Nogueira March 《Canadian Metallurgical Quarterly》1996,20(4):395-398
Two of the most important biochemical hepatic pathways in the liver are those that synthesize methionine and S-adenosylmethionine (SAM) through the methylation of homocysteine. This article reviews some recent findings in this laboratory, which demonstrate that ethanol feeding to rats impairs one of these pathways involving the enzyme methionine synthetase (MS), but by way of compensation increases the activity of the enzyme betaine:homocysteine methyl transferase (BHMT), which catalyzes the second pathway in methionine and SAM biosynthesis. It has been shown that despite the inhibition of MS, the enhanced BHMT pathway utilizes hepatic betaine pools to maintain levels of SAM. Subsequent to the above findings, it has been shown that minimal supplemental dietary betaine at the 0.5% level generates SAM twofold in control animals and fivefold in ethanol-fed rats. Concomitant with the betaine-generated SAM, ethanol-induced hepatic fatty infiltration was ameliorated. In view of the fact that SAM has already been used successfully in the treatment of human maladies, including liver dysfunction, betaine, shown to protect against the early stages of alcoholic liver injury as well as being a SAM generator, may become a promising therapeutic agent and a possible alternative to expensive SAM in the treatment of liver disease and other human maladies. 相似文献
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Teixeira A.L.J. Nogueira R.N. Andre P.S.B. Lima M.J.N. da Rocha J.R.F. 《Electronics letters》2005,41(1):30-32
A new scheme, based on Bragg gratings written in highly birefringent fibre that allows both increasing the channel density and relaxing the filter bandwidth requirements in future radio-over-fibre wavelength interleaved distribution networks, is presented and tested. 相似文献
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Immunohistochemical screening for monoclonal antibodies prepared by immunization of mice with a rat osteoblastic cell population led to identification of one antibody that reacted against a small population of cells present in the soft connective tissue compartment of 21 days fetal rat calvaria. The morphology of the cells and the immunohistochemical staining characteristics (a distinct intracellular granular pattern) suggested that the antibody might be reacting specifically against mast cells. We used combined histochemistry and immunohistochemistry to further characterize this antibody, designated RCJ102. Cryosections containing calvaria bone, soft connective tissues and skin were prepared from the top of the head of 21 days fetal rats, and from adult rats cryosections of lung, muscle, adipose tissue and small intestine were prepared. Some sections were labelled by indirect immunofluorescence with RCJ102; corresponding sections were labelled histochemically with toluidine blue. There was a direct correspondence between mast cells identified histochemically and cells labelling with RCJ102 in all tissues except intestine, in which the mast cell detectable by histochemistry were not labelled by RCJ102. These results suggest that the RCJ102 antibody will be a valuable new reagent for further elucidation of the heterogeneity described between connective tissue and intestinal mucosal mast cells. 相似文献
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Nelio D. Pizzolato Fabricio Broseghini Barcelos Luiz Antonio Nogueira Lorena 《International Transactions in Operational Research》2004,11(6):667-681
This study is concerned with the location of primary public schools. The public system should have the capacity to satisfy all the demand, although students may choose between public and private schools if they can afford the corresponding costs. A number of factors, such as questionable education quality, limited capacity, poor location and social preferences, secure a participation of about 30% to the private school system. The purpose of this study is both the evaluation of the existing public school network and a relocation proposal. The result of the former was the identification of areas with shortage and excess in school offer. The latter suggests school relocation using capacitated and uncapacitated models. ArcView, a software of the geographic information system (GIS) family, was employed, allowing the efficient handling of large problems and improving the presentation and evaluation of the findings. This methodology was applied to the primary public school network in the area of Vitoria, a state capital located in the southeast region of Brazil with about 300,000 inhabitants. Finally, the practical use of this study and its importance for planning purposes are discussed. 相似文献
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Nogueira FG Castro IA Bastos AR Souza GA de Carvalho JG Oliveira LC 《Journal of hazardous materials》2011,186(2-3):1064-1069
The leather industry produces a large quantity of solid waste (wet blue leather), which contains a high amount of chromium. After its removal from wet blue leather, a solid collagenic material is recovered, containing high nitrogen levels, which can be used as a nitrogen source in agriculture. In order to take more advantage of the collagen, it was enriched with mineral P and K in order to produce NPK formulations. The objective was also to evaluate the efficiency of such formulations as a nutrient supply for rice plants in an Oxisoil, under greenhouse conditions. The application of PK enriched-collagen formulations resulted in N contents in the vegetative parts and grains of rice plants which were equivalent or superior to those obtained with urea and commercial NPK formulations. 相似文献