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1.
Human trafficking is a global problem. In this paper, I seek to find the determinants of international human trafficking by using the US as a case study. Previous studies have drawn primarily from the migration literature, proposing hypotheses that focus on economic factors, the level of democracy and other “push” factors in the countries of origin that create incentives for individuals to migrate. However, we know that international human trafficking is an involuntary form of migration and may be influenced by additional factors. I hypothesize that factors that influence the cost–benefit calculation of the trafficker determine the volume of human trafficking, in addition to the factors that affect the size of the pool of trafficking victims. I test my theory using the negative binomial regression model. My results indicate that while income inequality within a country and poor protection of women's rights are likely to produce a specific pool of victims, it is the reduction of operational costs for the trafficker that increases the number of individuals who are trafficked.  相似文献   
2.
Methods of estimating unknown parameters of a trend function for trend-renewal processes are investigated in the case when the renewal distribution function is unknown. If the renewal distribution is unknown, then the likelihood function of the trend-renewal process is unknown and consequently the maximum likelihood method cannot be used. In such a situation we propose three other methods of estimating the trend parameters. The methods proposed can also be used to predict future occurrence times. The performance of the estimators based on these methods is illustrated numerically for some trend-renewal processes for which the statistical inference is analytically intractable.  相似文献   
3.
Background: Testosterone (TT) and dehydroepiandrosterone sulphate (DHEAS) are neurosteroids and their deficiencies constitute the hormone risk factors promoting the development of depression in elderly otherwise healthy men. We investigated the link between hypogonadism and depression in accordance with age and concomitant diseases in men with systolic HF using the novel scale previously dedicated for elderly population.

Methods: We analysed the prevalence of depression and severity of depressive symptoms in population of 226 men with systolic HF (40–80 years) compared to 379 healthy peers. The severity of depression was assessed using the Polish long version of Geriatric Depression Scale (GDS).

Results: In men aged 40–59 years the severity of depressive symptoms was greater in NYHA classes III–IV compared to NYHA classes I–II and reference group. In men aged 60–80 years depressive symptoms were more severe in NYHA class III-IV compared to controls (all p?≤?0.001). In multivariate logistic regression model in men aged 40–59 years advanced NYHA class was associated with higher prevalence of mild depression (OR?=?2.14, 95%CI: 1.07–4.29) and chronic obstructive pulmonary disease (COPD) with higher prevalence of severe depression (OR?=?69.1, 95%CI: 2.11–2264.3). In men aged 60–80 years advanced NYHA class and TT deficiency were related to higher prevalence of mild depression (respectively: OR?=?2.9, 95%CI: 1.3–6.4; OR?=?3.6, 95%CI: 1.2–10.63).

Conclusion: TT deficiency, COPD and advanced NYHA class were associated with higher prevalence of depression in men with systolic HF.  相似文献   
4.
La crise contemporaine de la vie rurale et agricole c'est produite simultanément avec une crise de la pensée et de la recherche critique: une analyse basée sur l'engagement à créer une société plus rationelle, démocratique et égalitaire. L'économie politique, le paradigme prédominant, a contribuée de façon importante à l'identification et à l'analyse des méchanismes économiques sur lesquels se développent la crise sociale. Mais celui-ci n'a tenu aucun compte d'enquêter sur la façon dont une crise est vécue par ceux qui en sont le plus touchés, et sur les perspectives de changement queue crise du genre peut offrir. Ceci est due d'un côtéà la nature des hypothèses théoriques de l'économie politique, ainsi que sur la façon dont les économistes politiques utilisent les méthodes des sondages dans leurs travaux empiriques. En utilisant les ressources offertes par la theorie sociale et les résultats de recherche primaire et empirique, cet article suggère de nouvelles directions pour la recherche critique de la vie rurale. Nous expliquons que ce genre de recherche devrait devenir plus hermaneutique et phénoménologique dans le but de concentrer sur les perceptions, l'analyse personnelle et les activités de ceux qui vivent dans les milieux ruraux, surtout lorsque ceux-ci essaient de préserver leurs communautés contre l'influence de l'extérieur. II n'est plus nécessaire, de présumer que les chercheur(e)s et leur sujets doivent demeurer détachés si la recherche est sérieusement scientifique et érudite. Cet article considère certaines implications théoriques, empiriques et historiques qu'apporte cet argument. The contemporary crisis in agriculture and rural life has been paralleled by a crisis in critical thinking and research: analysis informed by the commitment to a more rational, democratic and egalitarian society. Political economy, the currently dominant critical paradigm, has made important contributions to the identification and analysis of the economic mechanisms through which social crisis develops. But it has by and large failed to probe both the ways in which crisis is actually experienced by people enduring it and the real possibilities for change that a crisis situation might offer. This failure stems both from the nature of the theoretical assumptions which inform political economy and the manner in which political economists deploy methods of survey research in their empirical work. Using both the resources of social theory and the results of empirical, primary research, this paper attempts to suggest new directions for critical research into rural life. J t argues that this research should adopt a more explicitly hermeneutical and phenomenological focus which should put the perceptions, self-understandings and activities of rural people themselves, particularly as they strive to preserve their communities against outside forces, more fully at the centre of analysis. No longer should it be assumed that researchers and those studied must remain separate if research is to be truly scholarly and scientific. The paper addresses some possible theoretical, empirical and historical  相似文献   
5.
The receiver operating characteristic (ROC) curve is a graphical representation of the relationship between false positive and true positive rates. It is a widely used statistical tool for describing the accuracy of a diagnostic test. In this paper we propose a new nonparametric ROC curve estimator based on the smoothed empirical distribution functions. We prove its strong consistency and perform a simulation study to compare it with some other popular nonparametric estimators of the ROC curve. We also apply the proposed method to a real data set.  相似文献   
6.
Minimax estimation of a binomial probability under LINEX loss function is considered. It is shown that no equalizer estimator is available in the statistical decision problem under consideration. It is pointed out that the problem can be solved by determining the Bayes estimator with respect to a least favorable distribution having finite support. In this situation, the optimal estimator and the least favorable distribution can be determined only by using numerical methods. Some properties of the minimax estimators and the corresponding least favorable prior distributions are provided depending on the parameters of the loss function. The properties presented are exploited in computing the minimax estimators and the least favorable distributions. The results obtained can be applied to determine minimax estimators of a cumulative distribution function and minimax estimators of a survival function.  相似文献   
7.
Naturally occurring high levels of caregiver touch promote offspring development in many animal species. Yet, caregiver touch remains a relatively understudied topic in human development, possibly due to challenges of measuring this means of interaction. While parental reports (e.g., questionnaires, diaries) are easy to collect, they may be subject to biases and memory limitations. In contrast, observing touch in a short session of parent–child interaction in the lab may not be representative of touch interaction in daily life. In the present study, we compared parent reports (one-off questionnaires and diary) and observation-based methods in a sample of German 6- to 13-month-olds and their primary caregivers (n = 71). In an attempt to characterize touching behaviors across a broad range of contexts, we measured touch both during play and while the parent was engaged in another activity. We found that context affected both the quantity and types of touch used in interaction. Parent-reported touch was moderately associated with touch observed in parent–child interactions and more strongly with touch used during play. We conclude that brief one-off questionnaires are a good indicator of touch in parent–child interaction, yet they may be biased toward representing particular daily activities and particular types of touch.  相似文献   
8.
The statistical model is considered in which the collection of data from several independent populations is available only at random times determined by order statistics of lifetimes of a given number of objects. Each of the populations is distributed according to a general multiparameter exponential family. The problem is to estimate the mean value vector parameter of the multiparameter exponential family of distributions of the forthcoming observations. Under the loss function involving a weighted squared error loss, the cost proportional to the events appeared and a cost of observing the process, a class of optimal sequential procedures is established. The procedures are derived in two situations: when the lifetime distribution is completely known and in the case when it is unknown but assumed to belong to an exponential subfamily with an unknown failure rate parameter.  相似文献   
9.
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   
10.
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   
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