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91.
Block designs having a property described by Caliński (1971) and Saha (1976), referred to as C-property, are further considered. A necessary and sufficient condition for a block design to have the C-property is given by Saha (1976) and another by Ceranka and Koz?owska (1983). In this paper some methods for constructing such block designs are presented.  相似文献   
92.
Factors Shaping Workplace Segregation Between Natives and Immigrants   总被引:2,自引:0,他引:2  
Research on segregation of immigrant groups is increasingly turning its attention from residential areas toward other important places, such as the workplace, where immigrants can meet and interact with members of the native population. This article examines workplace segregation of immigrants. We use longitudinal, georeferenced Swedish population register data, which enables us to observe all immigrants in Sweden for the period 1990–2005 on an annual basis. We compare estimates from ordinary least squares with fixed-effects regressions to quantify the extent of immigrants’ self-selection into specific workplaces, neighborhoods, and partnerships, which may bias more naïve ordinary least squares results. In line with previous research, we find lower levels of workplace segregation than residential segregation. The main finding is that low levels of residential segregation reduce workplace segregation, even after we take into account intermarriage with natives as well as unobserved characteristics of immigrants’ such as willingness and ability to integrate into the host society. Being intermarried with a native reduces workplace segregation for immigrant men but not for immigrant women.  相似文献   
93.
Abstract

Background: Modifiable risk factors contribute to the pathogenesis of cardiovascular disease (CVD) and erectile dysfunction (ED). We aimed to compare the knowledge about the contribution of modifiable risk factors to the pathogenesis of CVD and ED. The impact of patients’ having modifiable risk factors on the awareness of their negative influence on the development of CVD and ED was examined.

Methods: To this multicenter cohort study, we included 417 patients with CHD who had been hospitalized in the cardiology or cardiac surgery department during the previous six weeks and underwent cardiac rehabilitation in one of the five centers. Knowledge about modifiable risk factors was collected. ED was assessed by an abridged IIEF-5 questionnaire. Comparisons between groups were conducted using the Student’s t-test, Mann–Whitney U test, and Kruskal–Wallis test. Relationships were analyzed with Spearman's rank correlation coefficient.

Results: The mean number of correctly identified risk factors for CVD was significantly higher than those for ED (3.71?±?1.87 vs. 2.00?±?1.94; p?<?.0001). Smoking was the most recognized risk factor both for CVD and ED. Dyslipidemia was least frequently identified as a risk factor for CVD. Sedentary lifestyle was the only risk factor whose incidence did not affect the level of patient knowledge.

Conclusions: Cardiac patients with ED know more about risk factors for CVD than ED. It is necessary to include information about the negative impact of modifiable risk factors on sexual health into education programs promoting healthy lifestyles in men with cardiovascular diseases.  相似文献   
94.
Introduction.?It was found that vitamin D may have a direct effect on adipocyte differentiation and metabolism and might be involved in the glucose regulation of insulin secretion, as suggested from the discovery of a nuclear localization of 1,25-(OH)2D3 in pancreatic islets. In recent years, several polymorphisms in the VDR gene which are able to alter the activity of VDR protein have been described. The BsmI and FokI polymorphisms were described in relation to obesity and type 2 diabetes.

The aim of the study was to find whether there are associations between BsmI and FokI polymorphisms and anthropometric (BMI, WHR, BP) and biochemical parameters describing metabolic syndrome.

Materials and methods.?Studied were 176 randomly selected men aged 25–65 years (mean: 51.99 years) with a mean BMI of 28.06 kg/m2. Two polymorphisms of the VDR gene (FokI and BsmI) were explored using the PCR-RFLP method. Serum glucose, insulin, total cholesterol, LDL, HDL, and TG were measured using commercially available kits.

Results.?It was found that BB carriers tend to have higher BMI (29.00 ± 3.74 versus 26.81 ± 3.76, p = 0.024) and waist circumference (101.79 ± 10.59 versus 96.23 ± 10.35, p = 0.014) compared with the bb genotypes. Similarly, FF and Ff carriers had higher fasting insulin levels than the ff genotypes (12.30 ± 10.26 versus 9.76 ± 5.88, p = 0.001 and 9.76 ± 5.88 vs. 6.35 ± 2.64, p = 0.008), and lover cHDL levels in comparison to ff genotypes (52.28 ± 10.02 versus 60.63 ± 16.58, p = 0.015 and 53.70 ± 12.03 versus 60.63 ± 16.58, p = 0.032. Besides these, no significant differences were found.

Conclusions.?The BsmI VDR polymorphism seems to influence BMI, while the FokI VDR polymorphism appears to affect insulin sensitivity and serum cHDL level.  相似文献   
95.
Marina Tsvetaeva’s 1934 “Chërt” (The Devil) forms a central part of the cycle of autobiographical prose she wrote in emigration. This article assembles clues to the hidden origins of the Devil she describes in prose about her grandfathers, some of it censored in pre-1990 editions of her works. Tsvetaeva’s Devil is not simply metaphysical: it has the unusual appearance of a Great Dane. Though she goes on to trace its appearances in the literature and culture of her childhood, some of its physical features (eyes, nose, colour and posture) link it with other people in her life. The vivid details of the Devil suggest relationships, though peculiarly mediated ones, to members of her own family, especially her maternal grandfather, Aleksandr Danilovich Mein. The poet describes herself using Pushkin’s poem “Utoplennik” to camouflage her own sense of self from her mother. Much of the rest of “The Devil” describes her recognition of the Devil in varying symbolic or even phonetic guises, tracing how the poet stayed faithful to him even after he ceased to appear visibly, how she found and read his symbols in surrounding reality—e.g., card games, toys, rituals for finding lost objects—and in unexpected, otherwise respectable, parts of society, including her own grandfather. As always, Tsvetaeva creates a story that affirms her identity as a poet and illustrates the work she had to do to achieve that identity.  相似文献   
96.
Abstract

Every day thousands of family photographs get abandoned in second hand bookshops, at flea markets, and internet auctions, losing their past and having their stories erased. Conversely, the same images get found, reappropriated, and assigned with new meanings. It is this process of giving the found photograph a new lease of life that I explore in this article. As I argue here, photographs continue to act as potent narrative tools even if we no longer have access to their subjects or producers. Not only do I show how anonymous photographs can be read and interpreted but also how they function as material objects that are collected, loved, treasured, and inevitably integrated into the lives of their new adopted families. I show, in particular, how both the content and the materiality of photographs makes them carriers of family history and private memory, as well as intersecting with other categories such as class and identity.  相似文献   
97.
Explicit formulae for analyzing an experiment carried out in a nested block design having the general balance property of some desirable pattern are presented. They follow from a randomization-derived mixed model, decomposed into stratum submodels. Attention is confined here to the combined analysis allowing the information from different strata to be joined together. This article is an extension of some results presented in Caliński and Kageyama (2000 Caliński , T. , Kageyama , S. ( 2000 ). Block Designs: A Randomization Approach, vol. I: Analysis . Lecture Notes in Statistics , vol. 150. New York : Springer .[Crossref] [Google Scholar]), where the theory underlying the considered analysis is given.  相似文献   
98.
Burk at al (1984) gave a results concerning the comparison of the length of the two different confidence intervals for variance ratio, when the construction of the intervals was based on the principle of “equal tails”11. The purpose of this paper is to be solve the similar problem in case of the principle of “minimal length”.  相似文献   
99.
Results of an exhaustive study of the bias of the least square estimator (LSE) of an first order autoregression coefficient α in a contaminated Gaussian model are presented. The model describes the following situation. The process is defined as Xt = α Xt-1 + Yt . Until a specified time T, Yt are iid normal N(0, 1). At the moment T we start our observations and since then the distribution of Yt, tT, is a Tukey mixture T(εσ) = (1 – ε)N(0,1) + εN(0, σ2). Bias of LSE as a function of α and ε, and σ2 is considered. A rather unexpected fact is revealed: given α and ε, the bias does not change montonically with σ (“the magnitude of the contaminant”), and similarly, given α and σ, the bias is not growing with ε (“the amount of contaminants”).  相似文献   
100.
This paper complements a recently published study (Janczura and Weron in AStA-Adv Stat Anal 96(3):385–407, 2012) on efficient estimation of Markov regime-switching models. Here, we propose a new goodness-of-fit testing scheme for the marginal distribution of such models. We consider models with an observable (like threshold autoregressions) as well as a latent state process (like Markov regime-switching). The test is based on the Kolmogorov–Smirnov supremum-distance statistic and the concept of the weighted empirical distribution function. The motivation for this research comes from a recent stream of literature in energy economics concerning electricity spot price models. While the existence of distinct regimes in such data is generally unquestionable (due to the supply stack structure), the actual goodness-of-fit of the models requires statistical validation. We illustrate the proposed scheme by testing whether commonly used Markov regime-switching models fit deseasonalized electricity prices from the NEPOOL (US) day-ahead market.  相似文献   
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