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A model stomach, containing a food matrix and a synthetic gastric fluid, was used to study the bactericidal effect of ingested wine on Listeria innocua. Volumes of wine equivalent to the ingestion of one glass and half a bottle, led, over a period of less than 2 h, to a reduction of 3 and 4 logarithmic cycles of the initial population respectively. The influence of ethanol and organic acids, wine constituents with known antimicrobial properties, was investigated. Ethanol exhibited a higher bactericidal effect than the mixture of the main wine organic acids. When testing the organic acids separately, malic and lactic acids were found to have the strongest effect. The combination of ethanol with the organic acids acted synergistically but to a lesser extent than wine itself. The results suggest that the ingestion of wine during a meal may diminish the quantity of Listeria persisting further in the alimentary tract.  相似文献   
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Increasingly clinicians attempt to base decisions regarding patient management on the results of clinical studies in addition to expert opinion and their own practical experience. In this article, the author reviews the published studies available to assist clinicians to make evidence-based decisions in three topics related to small volume red blood cell (RBC) transfusions for preterm infants; namely, studies examining the effects of RBC transfusions on possible symptoms of anemia such as tachypnea, apnea or other cardiorespiratory irregularities, studies investigating the collection and transfusion of umbilical cord blood and finally studies addressing the duration of storage and use of additive solutions for RBCs for transfusion to neonates. Based on the review of these studies, guidelines for small volume RBC transfusions in preterm infants are suggested.  相似文献   
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A versatile potentiometer that works with electrode arrays in flow injection and/or monosegmented flow systems is described. The potentiometer is controlled by a microcomputer that allows individual, sequential multiplexed or random accesses to eight electrodes while employing only one reference electrode. The instrument was demonstrated by monitoring an array of seven flow-through ion-selective electrodes for Ag(+) and for three electrodes for Cl(-), Ca(2+) and K(+). The figures of merit of the individual and multiplexed (summed) readings of the electrode array were compared. The absolute standard deviation of the measurements made by summing the potential of two or more electrodes was maintained constant, thus improving the precision of the measurements. This result shows that an attempt to combine the signals of the electrodes to produce a more intense signal in the Hadamard strategy is feasible and accompanied by a proportional improvement in the precision of individual measurements. The preliminary tests suggest that the system can allow for 270 determinations per hour, with a linear range from 1.0 x 10(-2) to 1.0 x 10(-4) mol l(-1) for the three di inverted exclamation markerent analytes. Detection limits were estimated as 3.1 x 10(-5), 3.0 x 10(-6) and 1.0 x 10(-5) mol l(-1) for Cl(-), Ca(2+) and K(+), respectively.  相似文献   
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There is a growing interest in cryogenic calorimeters with macroscopic absorbers for applications such as dark matter direct detection and rare event search experiments. The physics of energy transport in calorimeters with absorber masses exceeding several grams is made complex by the anisotropic nature of the absorber crystals as well as the changing mean free paths as phonons decay to progressively lower energies. We present a Monte Carlo model capable of simulating anisotropic phonon transport in cryogenic crystals. We have initiated the validation process and discuss the level of agreement between our simulation and experimental results reported in the literature, focusing on heat pulse propagation in germanium. The simulation framework is implemented using Geant4, a toolkit originally developed for high-energy physics Monte Carlo simulations. Geant4 has also been used for nuclear and accelerator physics, and applications in medical and space sciences. We believe that our current work may open up new avenues for applications in material science and condensed matter physics.  相似文献   
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Despite the relevance of the software evolution phase, there are few characterization studies on recurrent evolution growth patterns and on their impact on software properties, such as coupling and cohesion. In this paper, we report a study designed to investigate whether the software evolution categories proposed by Lanza can be used to explain not only the growth of a system in terms of lines of code (LOC), but also in terms of metrics from the Chidamber and Kemerer (CK) object-oriented metrics suite. Our results show that high levels of recall (ranging on average from 52 to 72 %) are achieved when using LOC to predict the evolution of coupling and size. For cohesion, we have achieved smaller recall rates (<27 % on average).  相似文献   
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Atmospheric combustion products from forest fires in the Brazilian Amazon and ‘Cerrado’ regions during the dry season (July–October) induce systematic deviations on the routine satellite techniques for the assessment of solar energy resource information. This study, based on clear-sky days, has shown model overestimations of the incoming solar radiation as high as 44%. On the average, clear-sky model overestimation was four times larger than that found for clear-sky days in regions outside the biomass-burning season. A positive correlation between the combustion products of black carbon, total aerosols, CO, N2O, CH4, and the number of fire spots counted by the AVHRR sensor from the NOAA series satellites suggests a possible mechanism for the parameterization of these effects on the radiation transfer methods.  相似文献   
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The objective was to assess food consumption among children attending non-profit nurseries in the Federal District, Brazil.A representative sample was obtained and stratified by income. Food intake among 678 children, between 4 and 82 months old, was analyzed in nine nurseries using the 24-h dietary recall and direct food weighing methods. In children under 13 months old mean intake was above AI between 93.6 to 100% for carbohydrates, proteins, vitamins B1, B2, B12, B6, and zinc. In children from 7-12 months 56.5% presented iron consumption below EAR. Calcium intake was above AI for 35.4% of children over 1 year old. For vitamins with EAR values, the prevalence of inadequate consumption was 53.2% for vitamin E, and 90% for folate for children over 12 months old. Iron and zinc intake was above UL for 6.4% and 32.5% of children under 1 year old, and 1.5% and 5.3% for the remaining children, respectively. Lipid percentage distribution range among children between 13 and 47 months old was within the acceptable range for only 16.2%. Nonetheless, children between 36 and 82 months of both genders presented mean intake below energy requirements. Inadequate consumption observed for some nutrients points to the need for improvements in the standard of meals and nutritional assistance offered to children enrolled in charitably run nurseries in the Federal District.  相似文献   
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