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161.
162.
We evaluated the effects of long-term testosterone replacement therapy (TRT) on the bone mineral density (BMD) in obese patients with metabolic syndrome (MS) and late-onset hypogonadism (LOH). Sixty men (mean age 57 ± 10) with low serum testosterone (T < 320 ng/dL) and MS regardless the presence of osteoporosis were enrolled. Forty men received intramuscular T-undecanoate (TU) four times/year for 36 months and 20 age-matched hypogonadal men with MS in whom T treatment was contraindicated were used as controls. Hormonal, biochemical markers, vertebral and femoral BMD by dual-energy x-ray absorptiometry were measured. At baseline, overall patients had mild osteopenia (lumbar BMD= 0.891 ± 0.097 g/cm(2); femoral BMD= 0.847 ± 0.117 g/cm(2)). TU induced a significant improvement of bone mass after 36 months (lumbar BMD=1.053 ± 0.145 g/cm(2); p < 0.002; femoral BMD=0.989 ± 0.109; p < 0.003 g/cm(2)) with a 5%/year increase and a significant reduction in hs-CRP without changes in body mass index. A direct relationship between serum T and BMD increments at the lumbar (r(2)?= 0.66, p < 0.0001) and femoral (r(2)?=0.52, p < 0.0001) sites was demonstrated. Study adherence was 50% without serious side effects. Long-term TRT in middle-aged men with LOH and MS determines a significant increase in both vertebral and femoral BMD related to increased serum T levels, probably independently from estradiol modifications.  相似文献   
163.
Bilingual education programs, which consist of doing a substantial part of the instruction in a language different from the native language of the students, exist in several countries like the United States, India, and Spain. While the economic benefits of knowing a second language are well established, the potential effects over the learning of other subjects have received much less attention. We evaluate a program that introduced bilingual education (in English and Spanish) in primary education in a group of public schools of the Madrid region in 2004. Under this program, students not only study English as a foreign language but also some other subjects (at least Science, History, and Geography) are taught in English. In order to evaluate the program, a standardized test for all sixth grade students in Madrid on the skills considered “indispensable” at that age is our measure of the outcome of primary education. Our results indicate that there is a clearly negative effect on the exam results for the subject taught in English, for children whose parents have less than upper secondary education. This negative effect is a composite of two phenomena: the effect of the program on the student's knowledge of the subject and a reflection of the student ability to do the test in their native language when English is the medium of instruction. Although we are not able to separate quantitatively these two effects, the composite effect has a relevant interest, because the results for exams taken in Spanish are the measures that determine academic progression in the Spanish system. In contrast with the previous result, there is no significant effect for anyone on mathematical and reading skills, which were taught in Spanish. (JEL H40, I21, I28)  相似文献   
164.
Research has shown that the perception of sexual harassment depends on factors such as gender, the situational context, the type of harassment, the ideology of the perceiver, the physical attractiveness of the harasser and victim and the relationship between them. This study focuses on examining the influence of physical attractiveness in the perception of a situation like sexual harassment. Through a questionnaire, 205 participants read a scenario in which a male worker (attractive vs. unattractive) engaged in gender harassment against a female colleague (attractive vs. unattractive). The participants then answered the measurements on the perception of harassment, responsibility, motivation and ideology. The main results were that the situation was more often perceived as sexual harassment when the victim of the harassment was physically attractive than when she was unattractive. Furthermore, the higher the participants’ acceptance of harassment myths the more they tended to blame the victim. We can conclude from this study the importance of the influence of certain myths or preconceived ideas about sexual harassment, which are found in both men and women, on how these situations are perceived.  相似文献   
165.
Female sex workers (FSWs) experience elevated risk for HIV and sexually transmitted infections (STIs) through unprotected sex with male clients, yet the complexity of these commercial relationships remains understudied. From 2010 to 2011, we explored FSWs' conceptualizations of various client types and related risk behavior patterns using semistructured interviews with 46 FSWs in Tijuana and Ciudad Juarez, Mexico, where FSWs' HIV/STI prevalence is increasing. Our grounded theory analysis identified four types of commercial relationships: nonregular clients, regular clients and friends, clients who “fell in love” with FSWs, and long-term financial providers who often originated from the United States. As commercial relationships developed, clients' social and emotional connections to FSWs increased, rendering condom negotiation and maintaining professional boundaries more difficult. Drug abuse and poverty also influenced behaviors, particularly in Ciudad Juárez, where lucrative U.S. clients were increasingly scarce. While struggling to cultivate dependable relationships in a setting marked by historical sex tourism from a wealthier country, some FSWs ceased negotiating condom use. We discuss the need for HIV/STI research and prevention interventions to recognize the complexity within FSWs' commercial relationships and how behaviors (e.g., condom use) evolve as relationships develop through processes that are influenced by local sociopolitical contexts and binational income inequality.  相似文献   
166.
The authors consider the estimation of a set S ? Rd from a random sample of n points. They examine the properties of a detection method, proposed by Devroye & Wise (1980), which relies on the use of a “naive” estimator of S defined as a union of balls centered at the sample points with common radius ?n. They obtain the convergence rate for the probability of false alarm and show that the smoothing parameter ?n can be used to incorporate some prior information on the shape of S. They suggest two general methods for selecting ?n and illustrate them with a simulation study and a real data example.  相似文献   
167.
Impulsivity (and related traits reward/punishment sensitivity and tolerance to delayed rewards) and gambling cognitions have been linked to gambling. However, their independent associations with gambling preferences and clinical status have never been dissociated. The current study applied a data-driven strategy to identify gambling preferences, based on gambling frequency in several modalities. The two resulting factors were used to classify gambling disorder patients (GDPs) and non-problem recreational gamblers (RGs) into Type I (preferring cards, casino games and skill-based bets) and Type II (preferring slot machines, lotteries/pools and bingo). Participants were assessed in impulsivity, delay discounting, reward/punishment sensitivity, gambling-related cognitions, gambling severity, gambling frequency and average amount gambled per episode. GDPs scored higher than RGs in positive and negative urgency, delay discounting, reward sensitivity and intensity of gambling-related cognitions, but less in lack of perseverance. Additionally, Type II gamblers had greater difficulties delaying gratification, whereas Type I gamblers showed higher cognitive distortion and reward sensitivity levels. In practical terms, the finding that some characteristics are equally pervasive in disordered gamblers independently of their preferences (affect-driven impulsivity), whereas others (distorted cognitions, reward sensitivity, delay discounting) are more prominent in one type or the other, provides a basis to establish targets’ priority in therapy.  相似文献   
168.
Inflation     
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169.
170.
The goal of this study is to analyze the quality of ratings assigned to two constructed response questions for evaluating the written ability of essays in Portuguese language from the perspective of the many-facet Rasch (MFR [15 J.M. Linacre, Many-facet Rasch Measurement, 2nd ed., MESA Press, Chicago, 1994. [Google Scholar]]) model. The analyzed data set comes from 350 written tests with two open-item tasks that were developed based on a rating process independently marked by two rater coordinators and a group of 42 raters. The MFR model analysis shows the measurement quality related to the examinees, raters, tasks and items, and classification scale that has been used for the task rating process. The findings indicate significant differences amongst the rater severities and show that the raters cannot be interchanged. The results also suggest that the comparison between the two task difficulties needs further investigation. An additional study has been done on the scale structure of the classification used by each rater for each item. The result suggests that there have been some similarities amongst the tasks and a need of revision for some criteria of the rating process. Overall, the scale of evaluation has shown to be efficient for a classification of the examinees.  相似文献   
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