Application of the Biased Spring Balance Weighing Design Theory to Estimation of Differences of Line Effects for Legume Content

The incidence matrix of a BIB design for v treatments has been used to construct a biased spring balance weighing design. Conditions under which an optimum biased spring balance weighing design exists are given. It is also shown how this theory may be utilized to obtain treatment and experiment designs to estimate differences in legume content between pair of lines in an experiment overseeded with grass species.     

A Measure to Evaluate the Closeness of Satterthwaite's Approximation

Satterthwaite's approximation of the distribution of a nonnegative linear combination of independent mean squares is addressed in this article. A measure is developed to quantify the closeness of this approximation by using certain optimization results given by THIBAUDEAU and STYAN (1985). The main advantage of the proposed measure is to provide a theoretical framework for determining conditions under which Satterthwaite's approximation may be inadequate. This is demonstrated in three examples portraying frequently encountered problems in analysis of variance.     

Multiple proteins with single activities or a single protein with multiple activities: The conundrum of cell surface NADH oxidoreductases

Reduction of the cell-impermeable tetrazolium salt WST-1 has been used to characterise two plasma membrane NADH oxidoreductase activities in human cells. The trans activity, measured with WST-1 and the intermediate electron acceptor mPMS, utilises reducing equivalents from intracellular sources, while the surface activity, measured with WST-1 and extracellular NADH, is independent of intracellular metabolism. Whether these two activities involve distinct proteins or are inherent to a single protein is unclear. In this work, we have attempted to address this question by examining the relationship between the trans and surface WST-1-reducing activities and a third well-characterised family of cell surface oxidases, the ECTO-NOX proteins. Using blue native-polyacrylamide gel electrophoresis, we have identified a complex in the plasma membranes of human 143B osteosarcoma cells responsible for the NADH-dependent reduction of WST-1. The dye-reducing activity of the 300 kDa complex was attributed to a 70 kDa NADH oxidoreductase activity that cross-reacted with antisera against the ECTO-NOX protein CNOX. Differences in enzyme activities and inhibitor profiles between the WST-1-reducing NADH oxidoreductase enzyme in the presence of NADH or mPMS and the ECTO-NOX family are reconciled in terms of the different purification methods and assay systems used to study these proteins.     

Optimal sampling and estimation strategies under the linear model

In some cases model-based and model-assisted inferences canlead to very different estimators. These two paradigms are notso different if we search for an optimal strategy rather thanjust an optimal estimator, a strategy being a pair composedof a sampling design and an estimator. We show that, under alinear model, the optimal model-assisted strategy consists ofa balanced sampling design with inclusion probabilities thatare proportional to the standard deviations of the errors ofthe model and the Horvitz–Thompson estimator. If the heteroscedasticityof the model is 'fully explainable’ by the auxiliary variables,then this strategy is also optimal in a model-based sense. Moreover,under balanced sampling and with inclusion probabilities thatare proportional to the standard deviation of the model, thebest linear unbiased estimator and the Horvitz–Thompsonestimator are equal. Finally, it is possible to construct asingle estimator for both the design and model variance. Theinference can thus be valid under the sampling design and underthe model.     

Balanced Sample Generation for Predicting the Mean of a Finite Population

Two algorithms for balancing samples are proposed. They permit to disminish the errors of a predictor. A simple linear regression superpopulation model generates the responses. The behavior of the predictor under two balancing algorithms is evaluated in a Montecarlo experiment. The data arose from the determination of the content of minerals and vitamins in feed.     

平衡超滤加改良超滤对婴幼儿体外循环术后肺功能的作用分析

目的:探究平衡超滤加改良超滤对婴幼儿体外循环术后肺功能的影响.方法:对我院2009年7月-2011年3月收治的45例先天性心脏病患儿按照随机数字表进行平均分组,分别为平衡超滤联合改良超滤组、改良超滤组及对照组,各15例,分别使用平衡超滤联合改良超滤、改良超滤及单纯体外循环治疗,观察三组患儿转流各时间段呼吸情况、炎性因子浓度及肺功能变化,分析平衡超滤加改良超滤对婴幼儿体外循环术后肺功能的影响.结果:体外循环结束后20 min三组患儿血清IL-6、TNF-α指标明显升高,且C组及M组较U组明显升高,而C组及M组组间比较无明显统计学差异;T4、T5时点三组患儿TNF-α浓度逐渐下降,U组较C组及M组下降明显,sICAM-1浓度明显高于T1时点,且C组及M组较U组明显升高,而C组及M组组间比较无明显统计学差异;三组患儿肺静态顺应性明显降低,肺泡-动脉氧分压梯度明显升高;T3及T4时点U组、M组患儿肺静态顺应性及氧合指数均明显高于C组,而肺泡-动脉氧分压梯度明显低于C组;U组肺静态顺应性及氧合指数明显高于M组和C组,且肺泡-动脉氧分压梯度明显低于后者.结论:体外循环疗法治疗先天性心脏病会不可避免地引起机体炎症反应,而应用平衡超滤加改良超滤可最大限度减轻炎症反应带来的并发症,降低患儿肺损伤发生风险,提高预后,保证生存质量.     

呼吸道感染临床实验室检查标本的评价

急性呼吸道感染(RTIs)是临床常见多发病,其病原体对抗生素耐药率的增加对诊断微生物学构成了严峻的挑战。临床微生物室对感染病原体的检出率较低,一般只有50%,且不同部位感染所采集的标本,其结果差异很大。本研究将评述呼吸道感染实验室检查标本采集的影响因素和常见病原体肺炎链球菌、流感嗜血杆菌、肺炎支原体、卡他莫拉菌、肺炎衣原体、嗜肺性军团病杆菌、呼吸道病毒、尿抗原试验的临床意义。