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721.
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   
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Abstract

Uncertainty is a fundamental characteristic of medical practice. Renee Fox described three types of uncertainty: limitations in the body of medical knowledge, incomplete mastery of existing knowledge, and distinguishing between limitations and mastery of knowledge. This investigation administered ten Likert-format questions about uncertainty to 171 incoming medical students at one state medical school Items were reliable over a six week test-retest, and validity was supported by correlations with an Intolerance of Ambiguity scale. Entering students recognized that uncertainty exists in medical knowledge and mastery of medical knowledge. Factor analysis of the ten item uncertainty scale revealed three dimensions: uncertainty of the profession, practice certainty, and growth in uncertainty. No significant differences in the uncertainty items, scale, or factors existed by demographic characteristics or medical specialty preferences. These findings suggest that students are aware of issues surrounding uncertainty in medicine as they begin medical school, but medical uncertainty at this early stage in medical socialization is not sufficiently powerful to be associated with medical specialty preference.  相似文献   
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725.
Abstract

Objective: Alcohol marketers have increasingly moved their advertising efforts into digital and social media venues. As a result, the purpose of this study is to investigate associations between students’ use of social media, their exposure to alcohol marketing messages through social media, and their alcohol-related beliefs and behaviors. Participants: Public and private university students (N = 637) participated November and December 2011 and April 2012. Methods: College students completed online surveys to measure their exposure to social and online media generally, as well as their alcohol-related digital media use and alcohol use. Results: Use of social media related to alcohol marketing predicted alcohol consumption and engaging in risky behaviors, whereas the use of social media more generally did not. Conclusions: Students’ use of alcohol-related social media–marketing content associates with their problem drinking. Results have implications for alcohol abuse reduction efforts targeted at college students and suggest the importance of considering social, cultural, and cognitive factors in campaign planning and design.  相似文献   
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A critical challenge facing today's organizational leaders is gaining their followers' trust and having them view leaders as effective in addressing turmoil and change. Using a downsizing scenario as the context, this field experiment examined how a leader's positivity and transparency impacted followers' perceived trust, defined in terms of willingness to be vulnerable, and effectiveness of their leader. To test the hypotheses, 304 participants were randomly assigned to one of the four conditions of high (low) leader positivity × high (low) leader transparency. Results of our mixed methods study indicated both the leader's level of positivity and transparency impacted followers' perceived trust and evaluations of leader effectiveness. Besides limitations and suggestions for future research, we conclude with the practical implications that positive, transparent leaders may have on building trust and perceived effectiveness among their followers.  相似文献   
728.
This paper explores theoretical and practical aspects (i.e. resources allocated, activities undertaken, actors/decisions involved) of corporate 'parenting' in the development of international service networks. A review of the relevant corporate strategy, supply-chain, networks and services management literature underpins a preliminary content (capability; market orientation) and process (top-down; bottom-up) typology of network parenting. This provides the structure for discussion of two telecommunications-sector case studies. Analysis of the data acknowledges the influence of generic network mechanisms (e.g. weak and strong social ties) but the parenting typology also highlights other mechanisms, the effectiveness of which appears contingent on specific parenting roles. The paper details these roles (labelled: governing; training; curating; facilitating) and makes some preliminary comments on the role trajectories (e.g. governing ↔ training) observed. The paper concludes with a discussion of possible directions for future work.  相似文献   
729.
This study assesses the degree to which a complexity absorption response enhances performance in an industry increasingly described as highly complex: acute-care hospitals. Business-level strategy, organizational structure, and analytical comprehensiveness are viewed as mechanisms through which executives can increase internal complexity. A case is made that hospitals are well served to pursue a hybrid (or combination) strategy, employ an organic structure, and engage in a high degree of information acquisition and use. In keeping with a complexity absorption view, results indicate that these elements generally exhibit stronger associations with performance as dynamism increases.  相似文献   
730.
An omnibus spending bill in 2014 directed the Department of Energy to analyze how effectively Department of Energy (DOE) identifies, programs, and executes its plans to address public health and safety risks that remain as part of DOE's remaining environmental cleanup liabilities. A committee identified two dozen issues and associated recommendations for the DOE, other federal agencies, and the U.S. Congress to consider, as well as other stakeholders such as states and tribal nations. In regard to risk assessment, the committee described a risk review process that uses available data, expert experience, identifies major data gaps, permits input from key stakeholders, and creates an ordered set of risks based on what is known. Probabilistic risk assessments could be a follow‐up from these risk reviews. In regard to risk management, the states, in particular, have become major drivers of how resources are driven. States use different laws, different priorities, and challenge DOE's policies in different ways. Land use decisions vary, technology choices are different, and other notable variations are apparent. The cost differences associated with these differences are marked. The net result is that resources do not necessarily go to the most prominent human health and safety risks, as seen from the national level.  相似文献   
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