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991.
Vásquez-Garibay E Stein K Méndez-Estrada C Pérez-Becerra E Romero-Velarde E Ibarra Gutiérrez I Ortiz Ortega MA García Iglesias T 《Archivos latinoamericanos de nutrición》2008,58(2):144-148
The severely malnourished child has dysfunction of the immune response that may increase the risk of morbidity or mortality due to infectious diseases, therefore, the purpose of this study was to demonstrate the effect of intensive nutritional support on the cellular and serum concentration of IL-2 and CD4+, as well as CD8+ T cells in children with severe protein energy malnutrition. A clinical assay was carried out in a tertiary care hospital. 10 severely malnourished children < 48 months of age who received formula without lactose via enteral feeding for two weeks and ad libitum for an additional two weeks were included. Cellular and serum concentrations of IL-2 and the subpopulation of CD4+ and CD8+ were obtained. A control group (n = 13) was included. A paired student t test for initial-final determinations and the Mann-Whitney Test for comparison with control group were used, and null hypothesis was rejected with a p value < 0.05. There was a noteworthy increase in the comparison between the initial vs. final percentage of the cellular expression of IL-2 (p < 0.001) and in the serum concentration of IL-2 (p = 0.001). Therefore, four weeks of nutritional recovery significantly restored the production of IL-2, independently of the nutrients involved in the process, although, the rate of restoration seems to depend on the severity of the children primary PEM. 相似文献
992.
993.
Arrays of parallel metallic nanowires are shown to provide a tunable, robust, and versatile platform for plasmon interconnects, including high-curvature turns with minimum signal loss. The proposed guiding mechanism relies on gap plasmons existing in the region between adjacent nanowire pairs and multiwire arrays. We focus on square and circular silver nanowires in silica, which we demonstrate to perform much better than previous schemes in terms of a relevant figure of merit measuring the degree of allowed integration. Our work provides the tools for designing plasmon-based interconnects and achieving a high degree of integration with minimum cross talk between adjacent plasmon guides, which should be relevant ingredients for future multiplexed biosensors. 相似文献
994.
Multiple linear regression (MLR), radial basis network (RB), and multilayer perceptron (MLP) neural network (NN) models have been explored for the estimation of toxicity of ammonium, imidazolium, morpholinium, phosphonium, piperidinium, pyridinium, pyrrolidinium and quinolinium ionic liquid salts in the Leukemia Rat Cell Line (IPC-81) and Acetylcholinesterase (AChE) using only their empirical formulas (elemental composition) and molecular weights. The toxicity values were estimated by means of decadic logarithms of the half maximal effective concentration (EC(50)) in microM (log(10)EC(50)). The model's performances were analyzed by statistical parameters, analysis of residuals and central tendency and statistical dispersion tests. The MLP model estimates the log(10)EC(50) in IPC-81 and AchE with a mean prediction error less than 2.2 and 3.8%, respectively. 相似文献
995.
996.
含盐量对MBER土壤固化剂加固土性能的影响试验 总被引:1,自引:0,他引:1
为分析MBER固化剂在咸水地区、盐渍土地区应用的可能性,通过试验分析了不同NaCl溶液浓度对MBER固化土的无侧限抗压强度、应力—应变关系和弹性模量的影响规律。结果表明,当NaCl浓度低于0.5%时,无侧限抗压强度及弹性模量均随溶液浓度的增加而增加,应力—应变曲线空隙闭合阶段随溶液浓度增加呈减小趋势;NaCl浓度高于0.5%时,无侧限抗压强度及弹性模量均随溶液浓度的增加而降低,应力—应变曲线空隙闭合阶段随溶液浓度增加呈增加趋势;弹性模量与无侧限抗压强度随NaCl浓度变化的趋势基本一致,两者存在较好的线性相关性;适量浓度的NaCl溶液对固化土早期强度的提升效果显著;NaCl浓度低于1%时,可应用于固化土工程建设。研究成果可指导MBER土壤固化剂在盐渍土地区的应用。 相似文献
997.
Sludge treatment wetlands (STW) are used as a dewatering technology in some European countries since the 80’s. Although the efficiency of this technology in terms of sludge dewatering and mineralisation is well known, design and operation parameters are yet to be standardised. The aim of this study is to develop a mathematical model capable of predicting the water loss with time, in order to optimise the feeding frequency enhancing sludge dewatering and expanding the lifespan of the system. The proposed model is validated with experimental data from one pilot and two full-scale STW. The scenarios considered indicate that the optimum feeding frequency decreases with the sludge layer height. In this way, systems with a sludge layer of 20 cm, 40 cm and 80 cm (corresponding to 2, 4 and 8 years of operation), should be fed every 2.5, 10 and 30-40 days, respectively. On the other hand, evapotranspiration (ET) has no effect on the feeding frequency, although it does increase the sludge dryness from 25% to 45% (for ET of 2.5 and 14.5 mm/d in the case of 20 cm of sludge height). According to the model output, the sludge loading rate is determined as a function of evapotranspiration, feeding frequency and sludge height. 相似文献
998.
Alejandra Alicia Peláez-Cid Vincent Romero-Hernández Ana María Herrera-González Alejandro Bautista-Hernández Oscar Core?o-Alonso 《中国化学工程学报》2020,28(2):613-623
Many different techniques may be used to remove industrial pollutants from wastewater. Adsorption using activated carbon has been reported to be an effective method. This work proposes the use of a vegetable residue (black sapote seeds) as a raw material for its synthesis. These carbons were chemically activated using phosphoric acid and carbonized at 673 and 873 K. Adsorption isotherms were constructed for the textile dyes on the carbons, and this data was treated using Langmuir's equation to quantitatively describe the adsorption process. The synthesized carbons were characterized using FTIR, EA, SEM, Nitrogen adsorption (specific surface areas of 879 and 652 m2·g-1), and their points of zero charge (2.1 and 2.3). It was possible to adsorb both heavy metals and textile dyes present in aqueous solutions and wastewaters using these activated carbons. Heavy metals were adsorbed almost completely by both carbons. Cationic dyes where adsorbed (58-59.8 mg·g-1) in greater amounts compared to anionic dyes (10-58.8 mg·g-1). The amount of anionic dyes adsorbed increased almost 30% by changing the pH of the solutions. One of the carbons was thermally regenerated on three occasions without losing its adsorption capacity and it was proved in a flow system. 相似文献
999.
An indirect enzyme-linked immunosorbent assay (ELISA) has been developed for detection of Pseudomonas fluorescens and related psychrotrophic bacteria in refrigerated meat. The ELISA uses polyclonal antibodies raised in rabbits against protein F from the cell envelope of Pseudomonas fluorescens AH-70. The anti-protein F antibodies were recovered from the crude antiserum by ammonium sulfate precipitation and conjugated to biotin. Commercial Extr Avidin-peroxidase conjugate was used to detect the biotinylated antibodies bound to their specific antigens. Subsequent enzymatic conversion of substrate gave distinct absorbance differences when assaying meat samples containing P. fluorescens strains of different origin as well as related psychrotrophic microorganisms. The detection threshold for the ELISA assay developed in this work was 10(4)-10(5) cfu cm(-2). 相似文献
1000.
Applied RCM2 algorithms based on statistical methods 总被引:1,自引:0,他引:1
Fausto Pedro García Márquez 《国际自动化与计算杂志》2007,4(2):109-116
The main purpose of this paper is to implement a system capable of detecting faults in railway point mechanisms. This is achieved by developing an algorithm that takes advantage of three empirical criteria simultaneously capable of detecting faults from records of measurements of force against time. The system is dynamic in several respects: the base reference data is computed using all the curves free from faults as they are encountered in the experimental data; the algorithm that uses the three criteria simultaneously may be applied in on-line situations as each new data point becomes available; and recursive algorithms are applied to filter noise from the raw data in an automatic way. Encouraging results are found in practice when the system is applied to a number of experiments carried out by an industrial sponsor. 相似文献