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871.
Lacerda IC Miranda RL Borelli BM Nunes AC Nardi RM Lachance MA Rosa CA 《International journal of food microbiology》2005,105(2):213-219
Sour cassava starch is a traditional fermented food used in the preparation of fried foods and baked goods such as traditional cheese breads in Brazil. Thirty samples of sour cassava starch were collected from two factories in the state of Minas Gerais. The samples were examined for the presence of lactic acid bacteria, yeasts, mesophilic microorganisms, Bacillus cereus and faecal coliforms. Lactic acid bacteria and yeasts isolates were identified by biochemical tests, and the identities were confirmed by molecular methods. Lactobacillus plantarum and Lactobacillus fermentum were the prevalent lactic acid bacteria in product from both factories, at numbers between 6.0 and 9.0 log cfu g(-)(1). Lactobacillus perolans and Lactobacillus brevis were minor fractions of the population. Galactomyces geothricum and Issatchenkia sp. were the prevalent yeasts at numbers of 5.0 log cfu g(-)(1). A species similar to Candida ethanolica was frequently isolated from one factory. Mesophilic bacteria and amylolytic microorganisms were recovered in high numbers at all stages of the fermentation. B. cereus was found at low numbers in product at both factories. The spontaneous fermentations associated with the production of sour cassava starch involve a few species of lactic acid bacteria at high numbers and a variety of yeasts at relatively low numbers. 相似文献
872.
Carrodeguas JA Burgos C Moreno C Sánchez AC Ventanas S Tarrafeta L Barcelona JA López MO Oria R López-Buesa P 《Meat science》2005,71(3):577-582
IGF2, insulin-like growth factor 2, is implicated in myogenesis and lean meat content. A mutation in a single base (A for G substitution) of the gene for IGF2 (position 3072 in intron 3) has been recently described as the cause of a major QTL effect on muscle growth in pigs [Van Laere, A. S, Nguyen, M., Braunschweig, M., Nezer, C., Collete, C., & Moreau, L. et al. (2003). Nature, 425, 832-836]. We describe here a rapid assay based on real time PCR (RT-PCR) to detect this mutation. We have evaluated the incidence of the mutation in commercial pig crosses, in three populations of purebred Iberian or Iberian×Duroc crosses, and in cured meat products and wild boars. The incidence of the mutation varies among these groups. Penetrance of the A mutation is about 80% in the commercial population. Purebred Iberian pigs were all homozygous G/G whereas crosses of Iberian pigs were heterozygous (90%) or homozygous A/A (10%). The implications of this gene for the selection of Iberian pigs are discussed. 相似文献
873.
Villa J De la Rosa I Miramontes G Quiroga JA 《Journal of the Optical Society of America. A, Optics, image science, and vision》2005,22(12):2766-2773
Recent studies have demonstrated that the phase recovery from a single fringe pattern with closed fringes can be properly performed if the modulo 2pi fringe orientation is estimated. For example, the fringe pattern in quadrature can be efficiently obtained in terms of the orientational phase spatial operator using fast Fourier transformations and a spiral phase spectral operator in the Fourier space. The computation of the modulo 2pi fringe orientation, however, is by far the most difficult task in the global process of phase recovery. For this reason we propose the demodulation of fringe patterns with closed fringes through the computation of the modulo 2pi fringe orientation using an orientational vector-field-regularized estimator. As we will show, the phase recovery from a single pattern can be performed in an efficient manner using this estimator, provided that it requires one to solve locally in the fringe pattern a simple linear system to optimize a regularized cost function. We present simulated and real experiments applying the proposed methodology. 相似文献
874.
Poli F Foroni M Bottacini M Fuochi M Burani N Rosa L Cucinotta A Selleri S 《Journal of the Optical Society of America. A, Optics, image science, and vision》2005,22(8):1655-1661
The modal cutoff of square-lattice photonic crystal fibers with a finite number of air-hole rings has been accurately investigated to our knowledge for the first time. By analyzing the leaky behavior of the second-order mode, we have obtained a phase diagram that describes the regions of single-mode and multimode operation as well as the endlessly single-mode regime. Furthermore, starting from these results, we have obtained the cutoff normalized frequency according to two different formulations of the V parameter previously adopted for fibers with a triangular lattice. A final comparison of the cutoff properties of fibers characterized by a square lattice and a triangular lattice has been carried out. 相似文献
875.
P.?M.?AmaralEmail author L.?Guerra?Rosa J.?Cruz?Fernandes 《Journal of Nondestructive Evaluation》2005,24(4):135-142
Two dynamic test methodologies, the resonance method and the ultrasonic method, are used for assessing the elastic behaviour
of granitic rocks. The experimental results obtained using two types of specimens: (i) rectangular beams (parallelepiped specimens);
and (ii) cylindrical specimens (rod specimens); show that the resonance method used in this work is more adequate when both
Young's modulus and Poisson's ratio are to be determined in these types of rocks. Moreover, it is demonstrated that test results
obtained by resonance techniques are less dependent on specimen's geometry, size, and even surface roughness. 相似文献
876.
Domenico?CantoneEmail author Calogero?G.?Zarba Rosa?Ruggeri?Cannata 《Journal of Automated Reasoning》2005,34(1):49-72
MLSS is a decidable fragment of set theory involving the predicates membership and set equality and the operators union, intersection, set difference, and singleton. In this paper we extend MLSS with the iterated membership predicate, that is, with a predicate denoting the transitive closure of the membership relation. We call the resulting language MLSS+. We prove that MLSS+ is decidable by providing a decision procedure for it based on Smullyan semantic tableaux. As an application of our results, we show how our decision procedure can be used as a black box in order to allow an interactive theorem prover to verify some basic properties of the ordinal numbers.This research was in part supported by murst grant prot. 2001017741 under the Italian project Ragionamento su aggregati e numeri a supporto della programmazione e relative verifiche. 相似文献
877.
Saccardo Sarni RO Suano de Souza FI Catherino P Kochi C Ceragioli Oliveira FL de Nóbrega FJ 《Archivos latinoamericanos de nutrición》2005,55(4):336-344
Mortality rate, anthropometric development and nutritional therapy with the use of World Health Organization guidelines (WHO) were assessed. In a cross-sectional retrospective study 191 hospitalized malnourished children were assessed. To classify and evaluate nutritional rehabilitation Z-score was used: weight-for-age (ZW), height-for-age(ZH) and weight-for-height(ZWH). The children were divided in three groups (G): GI (primary malnutrition--30,9%), GII (secondary malnutrition--51,7%) and GIII (children who were admitted as GI but during internation had an identified chronic disease--12%). Nutritional therapy used was based on WHO guidelines, with slight modifications. The formulas chosen were all industrialized: lactose-free polymeric formula (PLF) for children with diarrhea, low lactose polymeric formula (PLL) for children without diarrhea and cow's milk hydrolysate (H) for sepsis or chronic diarrhea. In the rehabilitation phase, all the children used PLL formula. Statistical analysis: Student's, chi-square tests, simple linear regression. The median age and mortality rate were 10,3 months and 4,2%, respectively. The GI and GII children were older than GIII (11vs12vs7months,p=0,02) and had shorter length of stay (20vs22vs37days,p=0,010). Mortality risks in GIII were twice as frequent as in GI+GII. Pneumonia, diarrhea and poor weight gain were the main diagnosis at admission. Tubes were used more frequently in GII+GIII than GI (p=0,004). Parenteral nutrition was indicated in 5,7% of children, more often in GIII than GI+GII (p=0,037). Tolerance of the initial formula wasn't satisfactory in 20% of the children. An improvement of 87% ZWH, 74,1% ZW and 22% was observed. ZW in GI and ZWH in GIII were the indices that showed the most effective gain during hospital stay. The modified WHO guidelines were effective in the multiprofessional treatment of malnourished children, resulting in good nutritional rehabilitation with low mortality rates. A high percentage of children admitted as primary malnutrition who had a chronic disease diagnosed was observed. The late diagnosis may be responsible for the high length of stay, formula intolerance and mortality risk. 相似文献
878.
879.
We implemented a laser system to be used in an optical transduction chain for the gravitational-wave bar detector AURIGA (Antenna Ultracriogenica Risonante per l'Indagine Gravitazionale Astronomica; Ultracryogenic Resonant Antenna for Astronomical Gravitational Investigation). This system is based on a Nd:YAG laser and includes quantum-limited power stabilization in the acoustic range, deep phase modulation and near-quantum-limited rf detection for locking onto optical cavities, and coupling to a single-mode polarization-maintaining optical fiber without deterioration of performance. Such a system has wide applications in optical metrology. 相似文献
880.
S De Rosa A Crispino A De Giulio C Iodice R Benrezzouk MC Terencio ML Ferrándiz MJ Alcaraz M Payá 《Canadian Metallurgical Quarterly》1998,61(7):931-935
A new inhibitor of human secretory phospholipase A2 (PLA2), cacospongionolide E (4a), has been isolated from the Tyrrhenian sponge Fasciospongia cavernosa. The structure was proposed on the basis of spectroscopic data and by chemical transformations. The absolute configuration of cacospongionolides 2a-4a was established using the modified Mosher's method. Cacospongionolide E was the most potent inhibitor toward human synovial PLA2, showing higher potency than the reference compound manoalide and exerting no signs of toxicity on human neutrophils. It showed high activity in the Artemia salina bioassay and moderate toxicity in the fish (Gambusia affinis) lethality assay. 相似文献