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991.
Accumulation of deicing salts in soils in an urban environment 总被引:4,自引:1,他引:3
Mary Ann Cunningham Eric Snyder Daniel Yonkin Morgan Ross Toren Elsen 《Urban Ecosystems》2008,11(1):17-31
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.
相似文献
Mary Ann CunninghamEmail: |
992.
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
993.
Coker AL Sanderson M Cantu E Huerta D Fadden MK 《Journal of American college health : J of ACH》2008,56(6):665-673
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
994.
Trepka MJ Kim S Pekovic V Zamor P Velez E Gabaroni MV 《Journal of American college health : J of ACH》2008,57(1):77-84
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
995.
996.
We investigated associations between later-life health and fertility history for women and men, using the British Household Panel Survey. We modelled health and its rate of change jointly with sample retention over an 11-year period. For women, childlessness is associated with limitation of activity for health reasons and faster acquisition of the limitation. High parity (four or more children) is associated with poorer health for both women and men. For the parous, this association is also found when age at first birth is controlled. Early parenthood is associated with poorer health. For parents of two or more children, a birth interval of less than 18 months is associated with having a health limitation and an accelerated rate of acquiring it. We conclude that biosocial pathways link parenthood careers and the later-life health of both women and men, and that implications of closely spaced births for parents merit further attention. 相似文献
997.
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
998.
X. Joan Hu Maria Lorenzi John J. Spinelli S. Celes Ying Mary L. McBride 《Lifetime data analysis》2011,17(2):215-233
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
999.
Eldad Davidov Stefan Thörner Peter Schmidt Stefanie Gosen Carina Wolf 《AStA Advances in Statistical Analysis》2011,95(4):481-500
In this study, we investigate and explain the level and change of six elements of group-focused enmity (GFE; see Zick et al.
in J. Soc. Issues 64(2):363–383, 2008) in Germany between 2002 and 2006: racism, xenophobia, anti-Semitism, homophobia, exclusion of homeless people and support
for rights of the established. For the data analysis, a representative 4-year panel study of the adult non-immigrant German
population collected during the years 2002–2006 is used, and the development of each GFE component is tested by using an unconditional
second-order latent growth curve model (LGM) (with full information maximum likelihood, FIML). We find that the level of 5
of the 6 components (racism, xenophobia, anti-Semitism, homophobia, exclusion of homeless people) displays an increase at
the beginning of the observed period followed by a decrease. However, the sixth aspect, rights of the established, displays
a continuous linear increase over time. The different developmental pattern stands in contrast to Allport’s (The nature of
prejudice. Perseus Books, Cambridge, 1954) hypothesis for the strong link between the components and their development over time. We try to explain this different
developmental pattern by several sociodemographic characteristics. This is performed by using a conditional second-order latent
growth curve model. 相似文献
1000.
In this paper we deal with Kolmogorov-Smirnov testson uniformity with completely or partly unknown limits. Tables of exact
percentage points are presented or referred using the wellknown determinant formula given by Steck (1971). It is shown that
these tables also give the percentage points for the analogous statistics of the test on truncated versions of known continuous
distributions with completely or partly unknown truncation limits.
We will give some examples of these applications. Among these are the tests on exponentiality and on Pareto distribution with
known shape parameter and unknown lower terminal. 相似文献