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151.
The current study assessed the use of standard conditional discrimination (i.e., listener) and textual/tact (i.e., speaker) training in the establishment of equivalence classes containing dictated names, tacts/textual responses, pictures and printed words. Four children (ages 5 to 7 years) diagnosed with autism were taught to select pictures and printed words in the presence of their dictated names, and to emit the tact or textual response corresponding to a presented picture or printed word. Both speaker and listener training resulted in the formation of stimulus classes for 3 of 4 participants.  相似文献   
152.
Objectives: To assess sex hormones, leptin and insulin-resistance in men with prostate cancer (PCa) and benign prostatic hyperplasia (BPH) and to study associations between androgens and histologic score of prostate tissue in PCa.

Subjects and methods: Two hundred ten men older than 45 years selected from 2906 participants of a population screening for PCa were studied: 70 with PCa, 70 with BPH and 70 controls (CG), matched by body mass index and age. Insulin, IGF-1, PSA, leptin, total, free (fT) and bioavailable testosterone (bT) and estradiol were measured. Each group was subdivided into two subgroups considering the presence of metabolic syndrome (MS); androgens and leptin levels were analyzed in the subgroups.

Results: Prostate cancer and BPH patients presented higher total, fT and bT levels than CG. IGF-1, insulin and HOMA index were higher in BPH than in the other two groups. PCa presented higher leptin [median (range) 6.5 (1.3–28.0) versus 4.8 (1.1–12.3) ng/ml; p?p?=?0.025] levels than CG. After dividing men considering the presence of MS, leptin was higher and total testosterone was lower in MS patients in all the groups.

Conclusions: It was observed a coexistence of an altered hormone profile with increased sex hormones and leptin in PCa patients, in accordance with the new perspective of PCa pathogenesis.  相似文献   
153.
The growing number of immigrants in the Madrid region raises several questions concerning the welfare of future native generations. The debates shift from increasing concern about the congestion of public services like education or healthcare, to how immigration helps to ease tension in relation to financing those services and other benefits to the region's general welfare. In order to evaluate the global effect, our analysis uses a generational accounting method which is applied to different productivity, interest rate and growth scenarios. The results show that the impact of immigrants is positive, with intergenerational distribution towards the currently most active taxpayers.  相似文献   
154.
The economic literature contains many parametric models for the Lorenz curve. A number of these models can be obtained by distorting an original Lorenz curve $L$ by a function $h$ , giving rise to a distorted Lorenz curve ${\widetilde{L}}=h\circ L$ . In this paper, we study, in a unified framework, this family of curves. First, we explore the role of these curves in the context of the axiomatic structure of Aaberge (2001) for orderings on the set of Lorenz curves. Then, we describe some particular models and investigate how changes in the parameters in the baseline Lorenz curve $L$ affect the transformed curve ${\widetilde{L}}$ . Our results are stated in terms of preservation of some stochastic orders between two Lorenz curves when both are distorted by a common function.  相似文献   
155.
A well-established body of literature holds that the construction of social representations of intelligence is guided by the subjective inexplicability about the target-topic and by the social identities of subjects. Within the general framework of the sociogenesis of social representations, this article aims to explore the role of social positions in organizing an individual’s reported action towards the object of representation. A theoretical model which examines the relations between social representations of the development of intelligence, parental goals and the authoritative parenting style was tested in sub-samples of educators, which included 227 mothers, 117 fathers and 122 mother-teachers. Structural equation modeling procedures indicated, as hypothesized, that specific socio-cognitive dynamics are relevant in shaping the patterns of relations with the object of representation, suggesting that these dynamics are a result of the organization of multiple discourses where content, social positions and behavioural interaction are strongly intertwined. Theoretical contributions of findings are discussed.  相似文献   
156.
This article presents a systematic review of qualitative studies focusing on human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) among Black men who have sex with men (BMSM) in the United States. We reviewed studies that were published between 1980 and 2014. Qualitative methods employed in the studies reviewed include in-depth interviews, focus groups, participant observation, and ethnography. We searched several databases (PubMed, PsychINFO, JSTOR, ERIC, Sociological Abstracts, and Google Scholar) for relevant articles using the following broad terms: “Black men” “Black gay/bisexual” or “Black men who have sex with men,” and “qualitative” and/or “ethnography.” We include 70 studies in this review. The key themes observed across studies were (1) heterogeneity, (2) layered stigma and intersectionality, (3) risk behaviors, (4) mental health, (5) resilience, and (6) community engagement. The review suggests that sexual behavior and HIV-status disclosure, sexual risk taking, substance use, and psychological well-being were contextually situated. Interventions occurring at multiple levels and within multiple contexts are needed to reduce stigma within the Black community. Similarly, structural interventions targeting religious groups, schools, and health care systems are needed to improve the health outcomes among BMSM. Community engagement and using community-based participatory research methods may facilitate the development and implementation of culturally appropriate HIV/AIDS interventions targeting BMSM.  相似文献   
157.
In this paper we measure inequality of opportunity in daycare and preschool services in Brazil. For this purpose, we construct an opportunity index that modifies the Human Opportunity Index proposed in the literature and used in Barros et al. (2009) to measure inequality in basic opportunities in Latin America and the Caribbean. Specifically, we construct an opportunity measure that includes not only attendance but also parental choice not to enroll children in daycare or preschool, using data from a supplementary questionnaire included in the 2006 version of Pesquisa Nacional por Amostra de Domicílios (PNAD). The results show that there are large differences between our opportunity index and the Human Opportunity Index for children aged 0–3 years old and considerably smaller differences for children aged 4–6 years old, which suggests that preschool may be closer to a basic opportunity than daycare.  相似文献   
158.
When a person is working with large scale Markov Decision Processes, he normally uses the policy iteration approach developed by Howard [1] and modified by White [3]. White's modification makes use of the method of successive approximations. Computational experience has shown that for many processes, the rate of convergence of the successive approximation is very slow. In this paper, techniques for speeding convergence are discussed. Numerical examples and computational experience which show the relative merits of the various approaches are presented.  相似文献   
159.
Social Indicators Research - The main objective of the article is twofold. On the one hand, it aims to offer a critical analysis of the different operationalizations of the concept of social...  相似文献   
160.
ABSTRACT

To determine the cerebral functionality associated with the perception and processing of erotic stimuli in men with different sexual orientation, this work evaluated the electroencephalographic activity (EEG) from several cortical areas, as well as subjective arousal in homosexual and heterosexual men during observation of an erotic film with heterosexual content. The heterosexual men rated the erotic video with higher general and sexual arousal than the homosexual participants. During observation of the neutral and erotic videos, both groups showed a decreased amplitude of the alpha band in prefrontal and parietal cortices, indicating increased attention. When watching the erotic video, the homosexual men showed an increased amplitude of the theta and fast bands only in the prefrontal cortex, which could be related to the cognitive processing of the erotic stimulus. These EEG results should broaden our knowledge of the cortical mechanisms related to the different perception and processing of erotic stimuli in men with different sexual orientations.  相似文献   
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