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151.
AbstractObjectives: To assess sex hormones in men with obesity and prostate cancer (PCa) and to study association between androgens and the pathogenesis biology of PCa in vitro.Subjects and methods: One hundred and eighty-one men older than 45?years selected from of a population attending to Urology departments screening for PCa, (78 participants without PCa and 103 patients with PCa). All participants were assessed for body mass index (BMI), age, Gleason score, and PSA. Endocrine profile was determined for LH, total testosterone (TT), 17β-estradiol (E2), prolactin and leptin. Biochemical profile (HbA1c, triacylglycerols and lipoproteins) was also determined. In vitro experiments were also performed, involving the study of 5α-dihydrotestosterone (DHT) and E2 in the presence of adipocyte-conditioned medium (aCM).Results: All variables were continuous and described a Gaussian distribution unless mentioned. To determine the relation of aggressiveness, variable were transformed into categories. Thus, PCa aggressiveness is associated with the increase of age and BMI (p?<?.0001) but with is decreased with TT and E2 (p?<?.05). Moreover, adipocyte-secreted molecules increase aggressiveness of PCa cells in vitro. Lastly, DTH but not E2 enables invasiveness in vitro.Conclusions: It was observed a coexistence of hormone axis profile alteration with sex hormones and BMI in PCa patients, in accordance with the new perspective of PCa pathogenesis. 相似文献
152.
Luis Beccaria Roxana Maurizio Ana Laura Fernández Paula Monsalvo Mariana Álvarez 《Journal of Economic Inequality》2013,11(4):555-580
Latin America experienced a long period of sustained growth since 2003 that positively impacted social and labor market indicators, including poverty. This paper contributes to the understanding of this process as it carries out a comparative study of poverty dynamics in five Latin American countries during 2003–2008. It analyzes the extent to which countries with different levels of poverty incidence diverge in terms of poverty exit and entry rates, identifies the relative importance of the frequency and impact of events associated to poverty transitions and examines how these events affect households with different characteristics. For this, a dynamic analysis of panel data is carried out using regular household surveys. Sizeable rates of poverty movements were observed in all five countries and it was found that a large proportion of household experienced positive events, mainly related to the labor market; however, only a small fraction of them actually exited poverty. Demographic events and public cash transfers proved to be of little relevance; in particular, the latter did not contribute much either to intensify poverty exits or to prevent poverty entries. Households with children experienced more (less) negative (positive) events than those without children. It appeared therefore that even when the economy behaved reasonably well at the aggregate level, high levels of labor turnover and income mobility (even of a negative nature) still prevail, mainly associated to the high level of precariousness and the undeveloped system of social protection that characterize the studied countries. 相似文献
153.
Luis F. Nuño 《Sociology Compass》2013,7(6):471-486
In the final decades of the 20th century policing in America was refashioned in the public image of community policing. Race‐neutral discourses dominate public and professional support for community‐oriented policing philosophies. In the contemporary era of hyper‐incarceration a focus on ethnoracial divisions grounded in the sociology of peculiar institutions is essential for documenting transformations in how the municipal police services are legitimized. Here I analyze how the public discourses of law‐and‐order center on distortions of social fact and public safety. Today the criminalization of immigrants is the latest turn in public discourses shaping patterns of ethnoracial visions and divisions. The carceral breadth of the neoliberal penal state extends beyond social structure, repackaged as race‐neutral ideology across the public sphere. 相似文献
154.
Luis T. Garcia 《Journal of sex research》2013,50(1):91-96
A study was conducted to investigate whether subjects make inferences about a female's sexuality based on her attitudes toward feminist issues. Based on the idea that both attitudes toward feminist issues and toward sexual traits are components of prototypes about females, it was hypothesized that females who expressed nontraditional attitudes on various feminist issues would be rated higher on a number of sexual traits than females who expressed more traditional attitudes. Male and female subjects were given information about a 19‐year‐old, single, female's attitudes on a number of issues related to women's occupational and domestic roles. The target's answers were manipulated so that in one condition she expressed traditional attitudes, and in a second condition she expressed nontraditional or feminist attitudes. The respondents were then asked to rate the target on traits reflecting a sexual and an evaluative dimension. As predicted, it was found that the female expressing nontraditional attitudes was rated higher in the sexual traits and was evaluated more negatively. The results were discussed in terms of the perceived incongruity between feminist attitudes and the traditional female prototype. 相似文献
155.
Yimeng Xie Luis A. Escobar William Q. Meeker 《Journal of Statistical Computation and Simulation》2017,87(8):1559-1576
Making predictions of future realized values of random variables based on currently available data is a frequent task in statistical applications. In some applications, the interest is to obtain a two-sided simultaneous prediction interval (SPI) to contain at least k out of m future observations with a certain confidence level based on n previous observations from the same distribution. A closely related problem is to obtain a one-sided upper (or lower) simultaneous prediction bound (SPB) to exceed (or be exceeded) by at least k out of m future observations. In this paper, we provide a general approach for computing SPIs and SPBs based on data from a particular member of the (log)-location-scale family of distributions with complete or right censored data. The proposed simulation-based procedure can provide exact coverage probability for complete and Type II censored data. For Type I censored data, our simulation results show that our procedure provides satisfactory results in small samples. We use three applications to illustrate the proposed simultaneous prediction intervals and bounds. 相似文献
156.
Guglielmo Maria Caporale Juncal Cunado Luis A. Gil-Alana 《Statistics and Computing》2012,22(2):349-358
This paper considers a general model which allows for both deterministic and stochastic forms of seasonality, including fractional (stationary and nonstationary) seasonal orders of integration, and also incorporating endogenously determined structural breaks. Monte Carlo analysis shows that, in the case of a single break, the suggested procedure performs well even in small samples, accurately capturing the seasonal properties of the series, and correctly detecting the break date. As an illustration, the model is estimated using four US series (output, consumption, imports and exports). The results suggest that the seasonal patterns of these variables have changed over time: specifically, in the second subsample the systematic component of seasonality becomes insignificant, whilst the degree of persistence increases. 相似文献
157.
In this paper we formulate the problem of constructing 1-rotational near resolvable difference families as a combinatorial optimization problem where a global optimum corresponds to a desired difference family. Then, we develop an algorithm based on scatter search in conjunction with a tabu search to construct many of these difference families. In particular, we construct three new near resolvable difference families which lead to an equal number of new 1-rotational near resolvable block designs with parameters: (46,9,8), (51,10,9) and (55,9,8). Our results indicate that this conjunction outperforms both scatter search and tabu search. 相似文献
158.
Ridge Regression techniques have been found useful to reduce mean square errors of parameter estimates when multicollinearity is present. But the usefulness of the method rest not only upon its ability to produce good parameter estimates, with smaller mean squared error than Ordinary Least Squares, but also on having reasonable inferential procedures. The aim of this paper is to develop asymptotic confidence intervals for the model parameters based on Ridge Regression estimates and the Edgeworth expansion. Some simulation experiments are carried out to compare these confidence intervals with those obtained from the application of Ordinary Least Squares. Also, an example will be provided based on the well known data set of Hald. 相似文献
159.
The purpose of this note is to gain insight on the performance of two well known operational Ridge Regression estimators by deriving the moments of their stochastic shrinkage parameters. We also show that, under certain conditions, one of them has bounded moments. 相似文献
160.
Baladandayuthapani V Ji Y Talluri R Nieto-Barajas LE Morris JS 《Journal of the American Statistical Association》2010,105(492):1358-1375
Array-based comparative genomic hybridization (aCGH) is a high-resolution high-throughput technique for studying the genetic basis of cancer. The resulting data consists of log fluorescence ratios as a function of the genomic DNA location and provides a cytogenetic representation of the relative DNA copy number variation. Analysis of such data typically involves estimation of the underlying copy number state at each location and segmenting regions of DNA with similar copy number states. Most current methods proceed by modeling a single sample/array at a time, and thus fail to borrow strength across multiple samples to infer shared regions of copy number aberrations. We propose a hierarchical Bayesian random segmentation approach for modeling aCGH data that utilizes information across arrays from a common population to yield segments of shared copy number changes. These changes characterize the underlying population and allow us to compare different population aCGH profiles to assess which regions of the genome have differential alterations. Our method, referred to as BDSAcgh (Bayesian Detection of Shared Aberrations in aCGH), is based on a unified Bayesian hierarchical model that allows us to obtain probabilities of alteration states as well as probabilities of differential alteration that correspond to local false discovery rates. We evaluate the operating characteristics of our method via simulations and an application using a lung cancer aCGH data set. 相似文献