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911.
Accumulation of deicing salts in soils in an urban environment   总被引:4,自引:1,他引:3  
Examining rates of deicing salt accumulation and leaching in urban soils is important for understanding the distribution and movement of salt in the environment. We examined autumn concentrations of deicing salts in soils in a moderately dense urban landscape in eastern New York State. The study area contrasted to the isolated, rural highways examined in previous studies. While NaCl was the most abundantly applied salt, Mg2+ (apparently from MgCl2, a secondary deicing salt) was the most abundant salt cation in soils. Moderate Na+ levels, and equivalent concentrations at depth and in surface samples, indicate that leaching of Na+ is rapid in this system. Leaching may ameliorate toxicity for land plants but accelerate inputs to aquatic systems. In contrast to rural highway studies, where salt levels declined rapidly with distance to pavement, Na+ remained elevated at the maximum distance measured. Airborne salt dispersal and dense networks of pavement likely contribute to widespread elevated salt levels. This semi-urban setting had salt levels high enough to be toxic to terrestrial plants and soil protozoa. Even moderate levels of development can have dramatic effects on salt inputs into soils and aquatic systems.
Mary Ann CunninghamEmail:
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912.
This paper describes research regarding factors predicting career optimism for a group of postsecondary students with disabilities (N = 208) who were enrolled in seven colleges and universities in four states. Career optimism was defined as a student's self-confidence regarding his or her ability to choose, maintain, and advance in an appropriate career. The proposed model incorporated variables related to employment discrimination and disincentives such as perceived impact of disability on one's education and quality of life, racial/ethnic status, gender, and presence of disability benefits. Results indicated that two aspects of "disadvantagement," specifically severity of perceived impact of disability and racial/ethnic status, were significant predictors of career optimism. Implications of the findings were discussed in terms of informational interventions, curricula, development of self-advocacy and self-determination, and research topics.  相似文献   
913.
OBJECTIVE AND PARTICIPANTS: The authors studied the prevalence of partner violence, by type, among Mexican American college women aged 18 to 35 years (N = 149; response rate = 85%). RESULTS: Twelve percent of women who reported a dating partner in the past year were physically or sexually assaulted, 12.1% were stalked, and 9.1% scored as psychologically abused. Among those experiencing partner violence, almost half experienced stalking and 89% reported psychological abuse. Few women (25%) who experienced physical violence believed violence was a problem in their relationship. CONCLUSIONS: Partner violence was prevalent in this population, and participants experienced many forms of violence. Because few women experiencing physical violence report that violence is a problem in their relationship, interventions must address perceptions of violence and its impact on women's mental and physical health in college populations.  相似文献   
914.
OBJECTIVE: The authors used a stratified cluster sampling design to inform campus sexually transmitted diseases prevention programs. PARTICIPANTS AND METHODS: They conducted a cross-sectional study of students (N = 1,130) at a large, urban, minority-serving university in South Florida using the 2004 National College Health Assessment Survey instrument. RESULTS: Of the 1,130 participants, 14.0% reported risky sexual behavior (having more than 1 sexual partner in 1 year and not using a condom the last time they had vaginal intercourse), and 11.9% reported consistent risky sexual behavior (having more than 1 partner in 1 year and not using condoms most or all of the time during the past 30 days). In multivariable analysis, past-month alcohol use had the strongest independent association with both risky and consistent risky sexual behavior. Illicit drug use was marginally significant in both models. CONCLUSIONS: Administrators should address the use of alcohol and other drugs on campus in planning interventions to promote safe sexual behavior.  相似文献   
915.
The EU Action Plan on Drugs (2005?C2008) calls for member states of the European Union to provide information on five key epidemiological indicators. These are: general population surveys, prevalence and patterns of problem drug use, drug related infectious diseases, drug related deaths and mortality of drug users, and demand for drug treatment. The goal is to improve the comparability of data across the Member States, which is a central task of the EMCDDA (European Monitoring Centre for Drugs and Drug Addiction). Ireland has made progress on a national level in meeting this obligation. Currently the core information systems used to monitor the drugs problem in Ireland and to inform policy making are in the health and law enforcement areas including treatment, mortality and crime data. The dominance of such objective indicators and treatment outcome measures has contributed to obscuring the view of communities experiencing drugs problems on a day to day basis. The data are summations of the individual experience of drug problems and contribute little to understanding the broader question of how drug problem effect communities. This article draws on a community drugs study to review the contribution of traditional indicators of drug problems and consider some of the limitations of this data. It then presents an analysis of community data to identify possible community indicators of drug problems.  相似文献   
916.
In an attempt to provide tools for assessing hospital utilization, this paper extends well-known models for recurrent events to address non-negligible event duration and presents a procedure for estimating the model parameters. The model extension is natural and easy to understand. Asymptotic properties of the associated inferences are derived adapting the well-developed methods based on the counting process formulation. Several specifications of the proposed modeling are illustrated with the hospitalization records of childhood cancer survivors from a health care insurance system that motivated this research. The usefulness and robustness of the proposed approach is demonstrated numerically via simulation.  相似文献   
917.
Previous research on volunteering finds significant differences by race and social class. We augment these findings by examining a largely ignored measure of social class: tenure status, the distinction between renters and homeowners. We test a theory that predicts people volunteer more if they have a “stake” in their community and we use the value of their home as a measure of the size of this stake, with renters having no stake at all, using data from the 2003 Panel Study of Income Dynamics. We find that although homeowners volunteer more than renters, the value of their home has no influence on their volunteer work. Length of residence in the neighborhood has a positive effect on volunteerism. Tenure status partially mediates the influence of race and family income on volunteering but not education.  相似文献   
918.
This paper examines stereotypes of lesbians held by college students. Multiple stereotypes are elicited from a free response trait listing task, followed by a sorting task. The results of the sorting task are submitted to cluster analysis and multidimensional scaling to reveal the complexity of cognitive representations of this group. Eight types are described, reflecting underlying distinctions between positive perceptions (e.g., lipstick lesbian, career-oriented feminist) and negative perceptions (e.g., sexually deviant, angry butch) and also between relative strength and weakness. The research is discussed in terms of cognitive perspectives on stereotyping and gender inversion theory. Suggestions for future research are provided.  相似文献   
919.
Since 1997, Labour has developed a wide range of policies on childcare services, care leaves and flexible working hours. In 2000, the term ‘work‐life balance’ was introduced and has been used by Government Departments and by the academic community with very little discussion of its meaning vis à vis the use of ‘family‐friendly’ policies, or the promotion of ‘work and family balance’. We explore the introduction of the term work‐life balance, the reasons for it, and its significance at the policy level, especially in terms of its implications for the pursuit of gender equality. We find that at the policy level, its use was more a matter of strategic framing than substantive change. Nevertheless, because of the UK Government's largely gender‐neutral approach to the whole policy field, it is important to make explicit the tensions in the continuing use of the term work‐life balance, particularly in relation to the achievement of gender equality.  相似文献   
920.
Doctors, nurses and other health care workers in the UK are said to be increasingly aware of the ‘risks of the job’ as a result of mounting verbal abuse, threats and assaults from patients and their relatives. In the late 1990s the UK government introduced a policy of ‘zero tolerance’, which it claimed was designed to minimize the risk of such violence. Current policy refers to the need to be tough on offenders and encourage a culture of respect. In this article we review this strategy and the reasons for its introduction and consider some of the potential consequences. The article starts with an account of the policy, the definition of violence that underpins it and how it has been measured, and assesses the evidence regarding prevalence. This is then interpreted in the context of wider policies of zero tolerance to crime, and debates about risk, anxiety and insecurity.  相似文献   
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