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721.
722.
The problem of gambling addiction is especially noteworthy among college students, many of whom have the resources, proximity, free time, and desire to become involved in the myriad options of gambling now available. Although limited attention has been paid specifically to college student gambling in the body of literature, there have been three published meta-analyses estimating the prevalence of probable pathological gambling among college students. The research presented is the largest and most comprehensive, presenting an up-to-date proportion of those students worldwide exhibiting gambling pathology as assessed by the South Oaks Gambling Screen, and is the first to include estimates of sub-clinical problem gambling. A thorough literature review and coding procedure resulted in 124 independent data estimates retrieved from 72 studies conducted between 1987 and the present, surveying 41,989 university students worldwide. The estimated proportion of probable pathological gamblers among students was computed at 6.13%, while the rate of problem gambling was computed at 10.23%. Statistical significance was found in the influence of the percentage of non-white students on pathological gambling rates. The implications of this and other moderator analyses such as age and year of studies, as well as recommendations for future practice in dealing with college students and gambling disorder on campus are outlined and described in detail. Suggestions and rationales for future avenues of research in the area are also described.  相似文献   
723.
Suppression of certain types of reflexive emotional responses is thought to temporarily deplete executive functions (EF), as evidenced by poorer performance on measures of EF, but does not deplete other, lower-order cognitive processes. This study examined whether similar decrements in performance on EF tests would occur following suppression of sexual arousal. A sample of 44 male college students underwent baseline cognitive assessment (EF and lower-order cognitive processes), followed by experimental manipulation consisting of exposure to sexually explicit audiovisual stimuli. Sexual arousal was monitored using penile plethysmography. In this study, 21 participants were assigned to a suppression condition and were instructed to suppress sexual arousal during the video, while 23 were assigned to an arousal condition and were instructed to allow themselves to become aroused. Following experimental manipulation, cognition was reassessed. Unexpectedly, results showed EF decrements in the arousal group but not in the suppression group. As expected, only EF was affected by experimental manipulation, with no group differences in lower-order cognitive processes. Thus, the findings suggest that sexual arousal is associated with temporary decrements in EF performance, at least among young, primarily White, male college students. The results contribute to understanding why sexually charged situations are sometimes associated with poor decisions or unsafe/reckless sexual practices.  相似文献   
724.
Seasonal flu vaccination rates are low for U.S. adults, with significant disparities between African and white Americans. Risk perception is a significant predictor of vaccine behavior but the research on this construct has been flawed. This study addressed critical research questions to understand the differences between African and white Americans in the role of risk perception in flu vaccine behavior: (1) What is the dimensionality of risk perception and does it differ between the two races?  (2) Were risk perceptions of white and African‐American populations different and how were sociodemographic characteristics related to risk for each group? (3) What is the relation between risk perception and flu vaccine behaviors for African Americans and whites? The sample, drawn from GfK's Knowledge Panel, consisted of 838 whites and 819 African Americans. The survey instrument was developed from qualitative research. Measures of risk perception included cognitive and emotional measures of disease risk and risk of side effects from the vaccine. The online survey was conducted in March 2015. Results showed the importance of risk perception in the vaccine decision‐making process for both racial groups. As expected, those who got the vaccine reported higher disease risk than those who did not. Separate cognitive and emotional factors did not materialize in this study but strong evidence was found to support the importance of considering disease risk as well as risk of the vaccine. There were significant racial differences in the way risk perception predicted behavior.  相似文献   
725.
ABSTRACT

The Safety and Health Improvement Program (SHIP) was designed to increase workers’ safety and health using supervisor/leadership training. SHIP was implemented and evaluated in a cluster randomized controlled trial with 20 supervisors and 292 construction crew members representing a high-risk industry. The intervention had three components: (1) computer-based training to teach supervisors ways to better support worker safety and work-life challenges; (2) supervisor behavioural self-monitoring to facilitate transfer of training to practice; and (3) team-based discussions with supervisors and work crew members to identify challenges and opportunities for improvement with 30, 60, and 90 day follow-up check-in meetings. Main effects for the intervention on perceptions of family supportive supervisor behaviors, team effectiveness, and work-life effectiveness were not found, suggesting that the pre-intervention context could help explain the lack of intervention effects. We found that the intervention was more beneficial for work crew members who had poorer pre-intervention perceptions of their supervisor (lower leader-member exchange) and lower perceived team cohesion, suggesting the important impact of the organisational context on intervention effects. We argue that perhaps these work crews were more ready for change and improvements in functioning than were the crews that were already functioning well.  相似文献   
726.
The purpose of the study was to examine the effects of acute androstenedione supplementation on hormone levels in older men at rest and during exercise. Men (n?=?11) between the ages of 58 and 69 were divided into an experimental (n?=?6; 62.33?±?2.57 y) and control (n?=?5; 60.2?±?1.02 y) groups. Each participant received an oral 300?mg dose of either androstenedione (experimental) or a cellulose placebo (control) for 7 d. Pre- and post-supplementation participants completed two separate, 20-min strength tasks consisting of leg extension and leg curls at different percentages of their 10-RM. Researchers collected blood samples pre-, during, and post-exercise. Blood samples were analyzed for testosterone, androstenedione, and estradiol levels. The researchers found a significant difference between pre- (4.36?±?56?ng/mL) and post- (5.51?±?0.35?ng/mL) testosterone levels, as well as pre- (0.88?±?0.20) and post- (7.46?±?1.25) androstenedione levels, but no significant differences between pre- and post-estradiol levels for either group. It appears that short-term androstenedione supplementation augmented acute testosterone responses to resistance exercise in older men. However, further study of this supplement is needed to determine any potential it may have in mitigating andropause.  相似文献   
727.
In 2008, this group published a paper on approaches for two‐stage crossover bioequivalence (BE) studies that allowed for the reestimation of the second‐stage sample size based on the variance estimated from the first‐stage results. The sequential methods considered used an assumed GMR of 0.95 as part of the method for determining power and sample size. This note adds results for an assumed GMR = 0.90. Two of the methods recommended for GMR = 0.95 in the earlier paper have some unacceptable increases in Type I error rate when the GMR is changed to 0.90. If a sponsor wants to assume 0.90 for the GMR, Method D is recommended. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
728.
Treatment effect in an observational study of relatively large scale can be described as a mixture of effects among subgroups. In particular, analysis for estimating the treatment effect at the level of an entire sample potentially involves not only differential effects across subgroups of the entire study cohort, but also differential propensities – probabilities of receiving treatment given study subjects’ pretreatment history. Such complex heterogeneity is of great research interest because the analysis of treatment effects can substantially depend on the hidden data structure for effect sizes and propensities. To uncover the unseen data structure, we propose a likelihood-based regression tree method which we call marginal tree (MT). The MT method is aimed at a simultaneous assessment of differential effects and propensity scores so that both become homogeneous within each terminal node of the resultant tree structure. We assess simulation performances of the MT method by comparing it with other existing tree methods and illustrate its use with a simulated data set, where the objective is to assess the effects of dieting behavior on its subsequent emotional distress among adolescent girls.  相似文献   
729.
In this paper, we describe an analysis for data collected on a three-dimensional spatial lattice with treatments applied at the horizontal lattice points. Spatial correlation is accounted for using a conditional autoregressive model. Observations are defined as neighbours only if they are at the same depth. This allows the corresponding variance components to vary by depth. We use the Markov chain Monte Carlo method with block updating, together with Krylov subspace methods, for efficient estimation of the model. The method is applicable to both regular and irregular horizontal lattices and hence to data collected at any set of horizontal sites for a set of depths or heights, for example, water column or soil profile data. The model for the three-dimensional data is applied to agricultural trial data for five separate days taken roughly six months apart in order to determine possible relationships over time. The purpose of the trial is to determine a form of cropping that leads to less moist soils in the root zone and beyond. We estimate moisture for each date, depth and treatment accounting for spatial correlation and determine relationships of these and other parameters over time.  相似文献   
730.
In this paper we argue that risk management can be an important source of competitive advantage for firms. For this to happen, managers must overcome four deep-seated notions about the management of risk: the myopic conception that risk is a collection of unconnected threats to the survival of a firm, the belief that risk management is largely a financial activity, the idea that risk management is solely a top management team task, and a blind faith that CEOs can continuously anticipate the risks that firms must address on an ongoing basis. Challenging these four misconceptions reveals that risk management can be an activity that is value creating, not just value preserving. Indeed, rather than indiscriminately shedding all types of risks, companies can develop new sources of competitive advantage by embracing those risks that they are relatively better at managing than their rivals. We illustrate our arguments by analyzing the risk management practices at CEMEX, the Mexican cement manufacturer.  相似文献   
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