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51.
W R Hewitt 《Journal of American college health : J of ACH》1992,40(6):288-289
The author reports on a study of the liquid nitrogen treatment of warts at the Rutgers University Student Health Center. He demonstrates that liquid nitrogen therapy is a safe, effective treatment method, appropriate for use by nurses and other primary providers in a college health setting. 相似文献
52.
Unions,PAC contributions,and the NAFTA vote 总被引:1,自引:0,他引:1
Political action committees (PACs), especially those controlled by organized labor and business, have been shown to affect
Congressional voting. We explore how PACs influenced the House of Representatives’ vote on the North American Free Trade Agreement
(NAFTA). The NAFTA vote is analyzed because organized labor strongly opposed the treaty while business generally supported
it and because of the straight-forward voting generated by its fast-track status. Probit analysis of a unique, unpublished
data set containing information about PAC and non-PAC contributions to the 1992 House election campaigns demonstrates that
Representatives who depended largely on labor PACs tended to oppose NAFTA, while Representatives who derived a large proportion
of their campaign contributions from business PACs tended to favor its passage. 相似文献
53.
Modeling for Risk Assessment of Neurotoxic Effects 总被引:2,自引:0,他引:2
The regulation of noncancer toxicants, including neurotoxicants, has usually been based upon a reference dose (allowable daily intake). A reference dose is obtained by dividing a no-observed-effect level by uncertainty (safety) factors to account for intraspecies and interspecies sensitivities to a chemical. It is assumed that the risk at the reference dose is negligible, but no attempt generally is made to estimate the risk at the reference dose. A procedure is outlined that provides estimates of risk as a function of dose. The first step is to establish a mathematical relationship between a biological effect and the dose of a chemical. Knowledge of biological mechanisms and/or pharmacokinetics can assist in the choice of plausible mathematical models. The mathematical model provides estimates of average responses as a function of dose. Secondly, estimates of risk require selection of a distribution of individual responses about the average response given by the mathematical model. In the case of a normal or lognormal distribution, only an estimate of the standard deviation is needed. The third step is to define an adverse level for a response so that the probability (risk) of exceeding that level can be estimated as a function of dose. Because a firm response level often cannot be established at which adverse biological effects occur, it may be necessary to at least establish an abnormal response level that only a small proportion of individuals would exceed in an unexposed group. That is, if a normal range of responses can be established, then the probability (risk) of abnormal responses can be estimated. In order to illustrate this process, measures of the neurotransmitter serotonin and its metabolite 5-hydroxyindoleacetic acid in specific areas of the brain of rats and monkeys are analyzed after exposure to the neurotoxicant methylene-dioxymethamphetamine. These risk estimates are compared with risk estimates from the quantal approach in which animals are classified as either abnormal or not depending upon abnormal serotonin levels. 相似文献
54.
55.
This study explored how students choose careers, their attitudes toward vocational education, and whether or not they would consider enrolling in a nontraditional vocational education program. 相似文献
56.
57.
The possibility that carbon dioxide emissions from fossil fuel use might lead to global warming has become a leading environmental concern. Many scientific and environmental organizations have called for immediate action to limit carbon dioxide production. For the most part, however, public debate has focused on a single policy instrument: a carbon tax applied to fossil fuels in proportion to their carbon content. We present a detailed model of the U.S. economy and use it to compare carbon taxes with two other instruments that could achieve the same reduction in carbon dioxide emissions: a tax on the energy content of fossil fuels (a BTU tax) and an ad valorem tax on fuel use. We find that carbon taxes can achieve a given reduction with the least overall effect on the economy, but with a large effect on coal mining. Energy taxes are fairly similar to carbon taxes but have slightly less impact on coal mining and slightly greater overall cost. In contrast, ad valorem taxes fall much more lightly on coal mining but have a much greater effect on the economy as a whole. 相似文献
58.
Barry R. Chiswick Yew Liang Lee Paul W. Miller 《The International migration review》2006,40(2):419-450
This article is concerned with the determinants of English language proficiency among immigrants in a longitudinal survey for Australia. It focuses on both visa category and variables derived from an economic model of the determinants of destination‐language proficiency among immigrants. Skills‐tested and economic immigrants have the greatest proficiency shortly after immigration, followed by family‐based visa recipients, with refugees having the lowest proficiency. Other variables the same, these differences disappear by 3.5 years after immigration for speaking skills; and although they diminish, they persist longer for reading and writing skills. The variables generated from the model of destination‐language proficiency (such as schooling and age at migration) are, in part, predictions of visa category, but they are more important statistically for explaining proficiency. 相似文献
59.
Nora Gustavsson Ph.D. Sandra Kopels J.D. M.S.W. 《Child and Adolescent Social Work Journal》1992,9(5):457-467
Child welfare workers and agencies are vulnerable to lawsuits. Recent court rulings have more clearly defined the liability of workers. The distinguishing variable is custody. Children injured while in the custody of the state are entitled to sue for damages. Children injured by their parent, even if under the supervision of a child welfare agency, are not entitled to claim a violation of their 14th Amendment rights. These cases are reviewed and strategies designed to minimize vulnerability are offered. 相似文献
60.
Joseph W. Ciarrocchi Ph.D. 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》1993,9(3):289-293
Rates of problem or probable pathological gambling were assessed in substance abusers seeking outpatient treatment in a publicly funded outpatient substance abuse treatment program. The South Oaks Gambling Screen (SOGS) was administered to 467 consecutive admissions at three different sites. Problem gamblers comprised 6.2 percent of the total (n=29), and 4.5 percent scored as probable pathological gamblers (n=21). These rates are two and one-half times greater than would be expected according to a recent state survey using the SOGS. Implications for assessment and treatment of problem gambling are discussed.The author expresses his appreciation to John Ramsay and the staff of Epoch Counseling Center for data collection; to Les Franklin for computational analysis; and Dr. Rachel Volberg for providing supplemental data from her Maryland State Gambling Survey. 相似文献