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961.
从任何一个角度看,全球无线手机通讯行业都在快速逼近危机的边缘。全世界已经有50多个国家的手机用户数量超过其实际人口数量。即使是在工业化国家中手机人均拥有率较低的美国,在用的手机数量也超过了2.7亿部(市场渗透率接近于90%)。今天,随着无线通讯市场的日益萎缩,  相似文献   
962.
Most organizations strive to recruit employees who can accommodate unpredictable changes, demonstrate adaptability, and interact effectively with a diversity of individuals. Nevertheless, recent advances in self regulation imply that leaders can instead cultivate such qualities in employees rather than merely attract individuals with these capacities. This paper delineates some of the leadership characteristics and behaviors that could diminish the fragility of employees to foster these qualities. First, a framework is developed that integrates four theories of self regulation—self discrepancy theory, personality systems interaction theory, optimal self esteem, and self salience. Second, this framework is applied to demonstrate how fragility undermines adaptive performance. Finally, this framework is used to show how many leadership constructs, such as self sacrificing, moral management, and transformational behavior, can curb this fragility and thus improve adaptive performance.  相似文献   
963.
We used a large database of 9 billion calls from 20 million mobile users to examine the relationships between aggregated time spent on the phone, personal network size, tie strength and the way in which users distributed their limited time across their network (disparity). Compared to those with smaller networks, those with large networks did not devote proportionally more time to communication and had on average weaker ties (as measured by time spent communicating). Further, there were not substantially different levels of disparity between individuals, in that mobile users tend to distribute their time very unevenly across their network, with a large proportion of calls going to a small number of individuals. Together, these results suggest that there are time constraints which limit tie strength in large personal networks, and that even high levels of mobile communication do not fundamentally alter the disparity of time allocation across networks.  相似文献   
964.

Objectives

Previous criminological scholarship has posited that network ties among neighborhood residents may impact crime rates, but has done little to consider the specific ways in which network structure may enhance or inhibit criminal activity. A lack of data on social ties has arguably led to this state of affairs. We propose to avoid this limitation by demonstrating a novel approach of extrapolatively simulating network ties and constructing structural network measures to assess their effect on neighborhood crime rates.

Methods

We first spatially locate the households of a city into their constituent blocks. Then, we employ spatial interaction functions based on prior empirical work and simulate a network of social ties among these residents. From this simulated network, we compute network statistics that more appropriately capture the notions of cohesion and information diffusion that underlie theories of networks and crime.

Results

We show that these network statistics are robust predictors of the levels of crime in five separate cities (above standard controls) at the very micro geographic level of blocks and block groups.

Conclusions

We conclude by considering extensions of the approach that account for homophily in the formation of network ties.  相似文献   
965.
Abstract

Objective: Gambling and alcohol use were compared for college and noncollege young adults in the US population. Participants: Participants were 1,000 respondents aged 18 to 21. Methods: Data were analyzed from a representative household sample of US young people aged 14 to 21 years old. Telephone interviews were conducted between August 2005 and January 2007. Results: After taking into account gender, age, race/ethnicity, and socioeconomic status, college student status did not predict gambling, frequent gambling, or problem gambling. In contrast, being a college student was associated with higher levels of alcohol use and problem drinking. Being male was the strongest predictor of both problem gambling and problem drinking. Blacks were less likely than whites to drink heavily; yet they were more likely than whites to gamble heavily. Conclusion: Young males should be targeted for prevention and intervention efforts for both problem gambling and problem drinking regardless of college student status.  相似文献   
966.
Abstract

Objective: Medication abortion with mifepristone and misoprostol has been available in the United States since 2000. The authors reviewed the first 46 medication abortion cases conducted at a university-based student health care clinic to determine the safety and feasibility of medication abortion in this type of clinical setting. Participants: Female patients presenting for medication abortion at a student health care clinic between October 1, 2006, and April 1, 2009. Methods: Retrospective consecutive case review. Results: Successful completion not requiring uterine aspiration occurred in 85% of the cases that were not lost to follow-up. Six cases (15%) required uterine aspiration for completion: 3 underwent uterine aspiration only; 3 had aspiration after failing an additional dose of misoprostol. Only 1 patient visited the emergency room. There were no hospitalizations. Conclusions: Medication abortion services in a student health care clinic are safe and feasible. However, additional treatment may be required with some patients.  相似文献   
967.
Abstract

Objective: To explore the predictive factors of student mental health within the college environment. Participants: Students enrolled at 7 unique universities during years 2008 (n = 1,161) and 2009 (n = 1,459). Methods: Participants completed survey measures of mental health, consequences of alcohol use, and engagement in the college environment. Results: In addition to replicating previous findings related to Keyes’ Mental Health Continuum, multiple regression analysis revealed several predictors of college student mental health, including supportive college environments, students’ sense of belonging, professional confidence, and civic engagement. However, multiple measures of engaged learning were not found to predict mental health. Conclusions: Results suggest that supportive college environments foster student flourishing. Implications for promoting mental health across campus are discussed. Future research should build on exploratory findings and test confirmatory models to better understand relationships between the college environment and student flourishing.  相似文献   
968.
969.
Abstract

Objective: This study examines ethnic identity and body image in black and white college females. Participants: Researchers surveyed 118 students at 2 universities, 1 traditionally white and 1 historically black. Methods: Correlations and multivariate analysis of variance (MANOVA) were used to investigate the relationship between race, ethnic identity, and body dissatisfaction. Results: There was no relationship between a woman's ethnic identity and her body dissatisfaction. Although white women scored higher on body dissatisfaction measures, women in both groups who had higher body dissatisfaction scores also choose smaller ideal body types. Results suggest that identification with an ethnic group may not shield women from being dissatisfied with their bodies. Conclusion: Colleges and universities should be aware that many women could experience body dissatisfaction and develop diverse programs that target women from different ethnic groups.  相似文献   
970.
Abstract

The authors surveyed 614 African American university students to determine the magnitude of cigarette use, identify risk factors, and develop models to predict smoking. More than half (58.3%) of the participants had smoked at least once, and 9.3% of that group were lifetime smokers. Among the lifetime smokers, 71.3% had smoked during the 30 days preceding the survey. More women (66.8%) than men (56.1%) had tried smoking and were classed as lifetime smokers. Residence, parental, and peer smoking (current and childhood) were associated with trying smoking; age, race/ethnicity, and marital status were additional factors for becoming a lifetime smoker. The risk of being a lifetime smoker was reduced when neither friends nor parents of the student smoked and the student viewed spirituality as important. The results of this study add to the growing understanding of health risk behaviors among African Americans and can be useful in reducing smoking.  相似文献   
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