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991.
R. Ushatov H. Power J. J. Rê go Silva 《Engineering Analysis with Boundary Elements》1994,13(4):371-381
In this work, uniform bicubic B-spline functions are used to represent the surface geometry and interpolation functions in the formulation of boundary-element method (BEM) for three-dimensional problems. This is done as a natural generalization of cubic B-spline curves, introduced by Cabral et al, for two-dimensional problems. Three-dimensional scalar problems, with particular applications to Laplace and Helmholtz equations, are considered. 相似文献
992.
AA de Paola CE Balb?o O Silva Netto A Mendon?a H Villacorta AC Vattimo IA Souza N Guiguer Júnior OP Portugal EE Martinez Filho 《Canadian Metallurgical Quarterly》1993,60(2):65-70
The author suggests a working classification of dermopertorators from analysis of his own designs and devices described in the literature for forming netlike skin grafts in the treatment of patients with large tissue defects. It is shown that the well-known dermoperforators require essential modernization. The most promising model is a device with plane knives whose simple technology allows their production to be organized in Soviet industry. 相似文献
993.
A protocol was designed for the rapid and efficient construction of cosmid libraries from cell-associated viral genomes available in very low quantities. Purification of viral DNA from cellular DNA was unnecessary. The vast excess of cellular DNA compensated for the limited amount of available viral DNA, enabling titration of the restriction endonuclease partial digest. A cosmid library of the turkey herpesvirus DNA genome was constructed from 1.5 micrograms of cellular DNA containing approximately 6 nanograms of viral DNA. 相似文献
994.
995.
G. Vale A. Rodrigues A. Rocha R. Rial A.M. Mota M.L. Gonçalves L.P. Fonseca J.L. Capelo 《Food chemistry》2010
The suitability of hyphenated USAED with HPLC separation and ET-AAS determination as a new rapid methodology for Se control in Se-enriched food supplements is demonstrated. Total Se determination and Se speciation are accomplished in a single sample treatment using low sample amounts (ca. 10 mg), and low extracting volume (1 mL). The total Se content in seven of the 10 Se-enriched supplements studied was in agreement with the values obtained after microwave pressurized acid digestion, MW, (test t, p = 0.05). The Se species studied were Se(IV), Se(VI), SeMet, SeMeSeCys, and SeCys2, being some of the most common found in the 10 supplements studied. Although SeMet was the Se species expected to be present at the highest concentration in most Se-enriched food supplements, we detected it in only three of the 10 samples studied. In the other seven samples, two of them had Se(IV) as the main Se species. The other five supplements had Se species that did not match with any of the five standards selected by us. We have also systematically demonstrated that ultrasonication does not alter the following Se species: Se(IV), Se(VI), SeMet, SeMeSeCys, and SeCys2. The new procedure can be easily adapted to more Se species and can be routinely used for Se control in Se-enriched food supplements. Concerning the supplements studied, our results suggest that stricter control on the Se content in enriched food supplements in terms of Se species will need to become mandatory. 相似文献
996.
A galactomannoglucan (GMG) with an estimated weight–average molar mass of 415,000 g/mol was obtained from an aqueous extract of the mesocarp of fruits of Syagrus oleracea (Mart.) Becc. by fractionation by Sephacryl S-300 HR and Sephadex G-25. Chemical and spectroscopic studies indicated that GMG has a chain of (1 → 4)-linked β-d-mannopyranosyl residues attached to an initial chain of (1 → 3)-linked β-d-galactopyranosyl residues and a terminal chain of (1 → 4)-linked α-d-glucopyranosyl residues which comprised galactose, mannose and glucose in the molar ratio of 30:33:37. Results of the present study indicated that the polysaccharide GMG of S. oleracea significantly inhibited gastric lesions induced by ethanol, showing a gastroprotective property. 相似文献
997.
Danielle Marques Vilela Gilberto Vinícius de M. Pereira Cristina Ferreira Silva Luís Roberto Batista Rosane Freitas Schwan 《Food microbiology》2010
This work was aimed at isolating and identifying the microbiota present during the semi-dry method of coffee processing using polyphasic methods and to evaluate microbial diversity with PCR-DGGE. Samples of Coffea arabica L. were collected during different processing stages in southern Minas Gerais, Brazil. The bacterial and fungal isolates were phenotypically characterised and grouped according to the ARDRA technique, in which the 16–23S and ITS1-5.8S regions of the rDNA were sequenced for species identification. The bacterial counts varied from 3.7 to 7 log CFU g−1. The yeast counts ranged from 3.4 to 6.9 log CFU g−1, and the filamentous fungal population varied from 2 to 3.7 log CFU g−1. Bacillus subtilis, Escherichia coli, Enterobacter agglomerans, Bacillus cereus and Klebsiella pneumoniae were the predominant bacteria detected during the processing of the coffee, and Pichia anomala, Torulaspora delbrueckii and Rhodotorula mucilaginosa were the dominant yeasts. All of the yeast and bacterial species detected by PCR-DGGE were isolated using culture-dependent methods, with the exception of one uncultivable bacterial species. Aspergillus was the most common genus among the filamentous fungal isolates. The use of polyphasic methods allowed a better characterization of the microbiota that is naturally present in semi-dry processed coffee. 相似文献
998.
Patrícia da Silva Malheiros Daniel Joner Daroit Nádya Pesce da Silveira Adriano Brandelli 《Food microbiology》2010
Commercial nisin was encapsulated in nanovesicles (mean diameter 140 nm) prepared from partially purified soy lecithin. Nisin-loaded liposomes and unencapsulated (free) nisin were initially tested in BHI medium and skim milk inoculated with Listeria monocytogenes and incubated for 48 h at 30 °C. At such abuse temperature conditions, free nisin showed better inhibitory than the liposomal counterparts. Subsequently, the effect of encapsulated or free nisin was evaluated in combination with refrigeration (7 ± 1 °C) in both whole (3.25% fat) and skim (0% fat) milk for up to 14 day. A decrease of 3–4 log cycles in L. monocytogenes counts was observed for free and encapsulated nisin at 0.5 mg/ml concentration. Liposome encapsulation of antimicrobial peptides may be important to overcome stability issues and interaction with food components. The utilization of nanovesicle-encapsulated nisin in combination with low temperatures appeared to be effective to control L. monocytogenes in milk, emphasizing the importance of hurdle technology to assure food safety. 相似文献
999.
Whasley F. Duarte Disney R. Dias José M. Oliveira José A. Teixeira João B. de Almeida e Silva Rosane F. Schwan 《LWT》2010,43(10):1564-1572
The main aim of this work was to produce fruit wines from pulp of gabiroba, cacao, umbu, cupuassu and jaboticaba and characterize them using gas chromatography–mass spectrometry for determination of minor compounds and gas chromatography-flame ionization detection for major compounds. Ninety-nine compounds (C6 compounds, alcohols, monoterpenic alcohols, monoterpenic oxides, ethyl esters, acetates, volatile phenols, acids, carbonyl compounds, sulfur compounds and sugars) were identified in fruit wines. The typical composition for each fruit wine was evidenced by principal component analysis and Tukey test. The yeast UFLA CA 1162 was efficient in the fermentation of the fruit pulp used in this work. The identification and quantification of the compounds allowed a good characterization of the fruit wines. With our results, we conclude that the use of tropical fruits in the production of fruit wines is a viable alternative that allows the use of harvest surpluses and other underused fruits, resulting in the introduction of new products into the market. 相似文献
1000.
Silva AP Guimarães DE Mizurini DM Maia IC Ortiz-Costa S Sardinha FL do Carmo MG 《Lipids》2006,41(6):535-541
The purpose of this study was to evaluate the effects of four isoenergetic diets of differing fat composition on blood lipid
profile and adiposity in young rats. Diets containing different lipid sources—partially hydrogenated vegetable oil (PHVO),
palm oil (PO), canola oil (CO), and soy oil (SO)—were fed to lactating rats during the 21 days of lactation, and then fed
to young males following weaning until the 45th, day of life. In vivo lipogenesis rate (LR), lipid content (LC), relative level of FA, and the activity of lipoprotein lipase (LPL) enzyme were
measured in epididymal adipose tissue (EPI). Fasting blood lipoproteins and LC in the carcass were also appraised. Body weight
of PO and PHVO groups was significantly higher than CO and SO groups from day 14 of lactation to day 45, despite the lower
food intake in the PHVO group. PO and PHVO groups presented higher LR and LC in EPI than SO and CO groups. Carcass fat content
was significantly higher in PHVO and PO groups than in CO and SO groups. The LPL activity in EPI was unaffected by dietary
lipids. PHVO group had increased total cholesterol and TAG concentrations in comparison with the PO group, and significantly
lower HDL level compared with the other groups. These results show that the kind of FA in the dietary lipid offered early
in life can affect lipid metabolism and adiposity. 相似文献