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In a group of 84 pairs of 11-year-old children of both sexes, the level of the alpha1-antitrypsin (alpha1-AT) were ascertained in the autumn and spring. Although the mean levels of alpha1-AT in the two seasons hardly differed, the highly significant seasonal changes in the distribution curves of alpha1-AT values were noted in boys, whereas the levels showed higher stability in girls. 相似文献
224.
This paper analyzes the network of passes among the players of the Spanish team during the last FIFA World Cup 2010, where they emerged as the champion, with the objective of explaining the results obtained from the behavior at the complex network level. The team is considered a network with players as nodes and passes as (directed) edges. A temporal analysis of the resulting passes network is also done, looking at the number of passes, length of the chain of passes, and to network measures such as player centrality and clustering coefficient. Results of the last three matches (the decisive ones) indicate that the clustering coefficient of the pass network remains high, indicating the elaborate style of the Spanish team. The effectiveness of the opposing team in negating the Spanish game is reflected in the change of several network measures over time, most importantly in drops of the clustering coefficient and passing length/speed, as well as in their being able in removing the most talented players from the central positions of the network. Spain’s ability to restore their combinative game and move the focus of the game to offensive positions and talented players is shown to tilt the balance in favor of the Spanish team. 相似文献
225.
One of the most important issues to resolve in parts manufactured from rapid manufacturing (RM) technologies is to know their behavior working under real conditions. Total quality manufacturing (TQM) is only possible if mechanical properties are well known in the design stage depending on the processing parameters. This work is mainly focused on testing of several samples made with different selective laser sintering (SLS) parameters and technologies. This procedure is the starting point to establish a basis for designing for RM and the standardization of RM testing. The experiments and the analysis of variance (ANOVA) analyzed the effects of several factors on mechanical properties. The SLS technologies were 3DSystem and EOS. The results show which factor has a large effect on the variables and the interaction between them. The conclusions are very useful for developing rules for designing (designing for RM) and creating new standard rules (ISO, AISI, and DIN) for RM materials and parts testing. The ANOVA gives a better knowledge of the effects of these factors and eliminates unimportant parameters. 相似文献
226.
The problem of prediction in time series using nonparametric functional techniques is considered. An extension of the local linear method to regression with functional explanatory variable is proposed. This forecasting method is compared with the functional Nadaraya–Watson method and with finite‐dimensional nonparametric predictors for several real‐time series. Prediction intervals based on the bootstrap and conditional distribution estimation for those nonparametric methods are also compared. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
227.
Subthreshold Na+-dependent theta-like rhythmicity in stellate cells of entorhinal cortex layer II 总被引:13,自引:0,他引:13
The oscillation of membrane potential in mammalian central neurons is of interest because it relates to the role of oscillations in brain function. It has been proposed that the entorhinal cortex (EC), particularly the stellate cells of layer II (ECIIscs), plays an important part in the genesis of the theta rhythm. These neurons occupy a key position in the neocortex-hippocampus-neocortex circuit, a crucial crossroad in memory functions. Neuronal oscillations typically rely on the activation of voltage-dependent Ca2+ conductances and the Ca2+ -dependent K+ conductance that usually follows, as seen in other limbic subcortical structures generating theta rhythmicity. Here we report, however, that similar oscillations are generated in ECIIscs by a Na+ conductance. The finding of a subthreshold, voltage-gated, Na+ -dependent rhythmic membrane oscillation in mammalian neurons indicates that rhythmicity in heterogeneous neuronal networks may be supported by different sets of intrinsic ionic mechanisms in each of the neuronal elements involved. 相似文献
228.
从分析工业建筑的个性与共性入手,论述了建筑专业应是工业建筑设计的主体专业,个性和共性是一个事物的两个方面,两者必须并重。对工业建筑而言,既要把握工业建筑设计中工艺的特殊需要,又要把握工业建筑中人对空间的共性需求。 相似文献
229.
The effects of proline and serine dipeptides containing phenylalanine, alanine and leucine on the behaviour of receptors of Tetrahymena were investigated. Only proline-containing dipeptides were able to develop positive imprinting, and the activity depended on which other amino acid was present in the dipeptide. In contrast to the positive imprinting effect of the dipeptides Pro-Phe and Pro-Ala, the dipeptide Pro-Pro and Pro-Leu caused negative imprinting. Serine dipeptides produced negative imprinting in all cases. The possible importance of proline in the evolution of hormone specificity is discussed. 相似文献
230.
添加剂对AN多变晶型影响研究 总被引:1,自引:0,他引:1
本文运用热分析的方法对四十余种无机、有机添加剂和几种表面活性剂及水分对硝酸铵(AN)晶型转变的影响进行了研究。结果表明这些添加剂对AN的影响应为多种因素的综合结果。 相似文献