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The sampling designs dependent on sample moments of auxiliary variables are well known. Lahiri (Bull Int Stat Inst 33:133–140, 1951) considered a sampling design proportionate to a sample mean of an auxiliary variable. Sing and Srivastava (Biometrika 67(1):205–209, 1980) proposed the sampling design proportionate to a sample variance while Wywiał (J Indian Stat Assoc 37:73–87, 1999) a sampling design proportionate to a sample generalized variance of auxiliary variables. Some other sampling designs dependent on moments of an auxiliary variable were considered e.g. in Wywiał (Some contributions to multivariate methods in, survey sampling. Katowice University of Economics, Katowice, 2003a); Stat Transit 4(5):779–798, 2000) where accuracy of some sampling strategies were compared, too.These sampling designs cannot be useful in the case when there are some censored observations of the auxiliary variable. Moreover, they can be much too sensitive to outliers observations. In these cases the sampling design proportionate to the order statistic of an auxiliary variable can be more useful. That is why such an unequal probability sampling design is proposed here. Its particular cases as well as its conditional version are considered, too. The sampling scheme implementing this sampling design is proposed. The inclusion probabilities of the first and second orders were evaluated. The well known Horvitz–Thompson estimator is taken into account. A ratio estimator dependent on an order statistic is constructed. It is similar to the well known ratio estimator based on the population and sample means. Moreover, it is an unbiased estimator of the population mean when the sample is drawn according to the proposed sampling design dependent on the appropriate order statistic.  相似文献   
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The purpose of the study was to examine in the blood of overweight men aged from 62 to 83 years, the relationships between age and insulin resistance, selected parameters of the oxidative stress, and the antioxidant defense system. The population studied was divided into two groups: the group ‘young-old’ consisted of men aged 62 to 74 years old, and the group ‘old-old’– of men aged between 75 and 83 years. The total antioxidative status (TAS) and concentrations of thiobarbituric acid reactive substances (TBARS) were measured in the blood plasma. In the serum samples, the levels of antibodies against oxidized LDL (oLAB), glucose, total cholesterol, HDL-cholesterol, triglycerides and insulin were measured. Homeostasis Model Assessment of Insulin Resistance (HOMAIR) was calculated. Concentration of reduced glutathione (GSH) and glutathione peroxidase activity (GPx) were determined in the red blood cells hemolysate. The results of the study did not show significant differences between groups investigated with respect to concentrations of TBARS, TAS, GSH and GPx. However, significantly higher concentrations of glucose and antibodies against oxLDL (p < 0.05) were observed in the group of men over 74 years old in comparison to the group of ‘young-old’ men. It was indicated that the increased insulin resistance and hyperglycemia in elderly men are related to body mass and that they cause intensified oxidative modifications of LDL.  相似文献   
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The aim of therapeutic help in marital crisis is to break the vicious circle of mutual hurtful accusations. The method that the authors present below involves a group of couples working within a closed cycle of meetings. In the course of successive group meetings, the various couples act as reflecting teams (RTs) for each other. This achieves two objectives: the couple recounting their crisis receives nonthreatening feedback, which helps them to implement positive changes and break out of the self-perpetuating destructive interaction. In addition, the couples acting as the RT learn nonjudgmental, nontheorizing and affirmative communication.  相似文献   
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The developmental neurotoxicity of methylmercury (MeHg) in humans has been described following catastrophic events in Minamata Bay, Japan and in Iraq, and following the exposure to lower doses elsewhere in the world. The most common route of MeHg exposure in humans is through the intake of contaminated food, especially fish. Although the precautions against the ingestion of potentially contaminated food during pregnancy are well recognized, precautions against the ingestion of MeHg during lactation are not so uniformly recognized. However, the continued development of the central nervous system during the early postnatal period serves to prolong the period during which this critical system is susceptible to the toxic insult of MeHg. Because no direct method is available to quantitatively assess the lactational transfer of MeHg to humans, a computer-aided simulation method was developed. An available gestational physiologically based pharmacokinetic model was refined and expanded to include parameters and algorithms specific for the elimination of MeHg in breast milk. The predictions of the completed model were compared with experimental data obtained from rodents, and the model parameters were allometrically scaled to humans. Finally, the model was validated by comparing its predictions against the available clinical data for MeHg distribution and elimination in mothers and their nursing infants. This model incorporated current and previous maternal exposures to MeHg to accurately predict the kinetics of MeHg excretion in breast milk and the daily intake by the nursing infant. This model may be used to quantify MeHg intake by the nursing infant, under different rates of maternal MeHg ingestion.  相似文献   
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It is claimed that tax policy is neither time- nor space-independent due to cross-border tax base mobility, which induces spillovers. Specifically, fiscal shocks in one country are supposed to have an impact on fiscal policies in other countries. Different types of taxes influence economies differently. This paper addresses the question of their impact on government debt. Within a framework of spatial econometric modeling, we evaluate the impact of capital, labor and consumption taxes on public debt in 34 European countries in 2002–2011, and find strong spatial spillovers. We show that a consumption tax and, to a lesser degree, a capital tax significantly affect the sovereign debt, and that the global relations play a leading role (i.e. dominate the local ones) in shaping fiscal policy.  相似文献   
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本文讨论了建筑设备研究所在计算机辅助工程研究中的一些问题,70年代中期该研究所就开始用计算机设计机器及其部件,后来研究所购买了一些相关软件同时也开发了自己的设计软件并在液压起重机和其它建筑机械的设计计算中得到了应用。70-80年代计算机主要用于压力的分析与测量,机械的振动与稳定性分析,研究所从事机械设计、计算机数据库安全性研究及生态学、工效学方面的研究。在此也感谢其它国家的学者在计算机应用方面的交流与合作。  相似文献   
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