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991.
Some controversy exists about the relative frequency of criminal and self-defense gun use in the United States. Using data from a national random-digit-dial telephone survey of over 1,900 adults conducted in 1996, we find that criminal gun use is far more common than self-defense gun use. This result is consistent with findings from other private surveys and the National Crime Victimization Surveys. In this survey, all reported cases of criminal gun use and many cases of self-defense gun use appear to be socially undesirable. There are many instances of gun use, often for intimidation, that are not reported to the police and may not appear in official crime statistics. 相似文献
992.
Barrios LC Everett SA Simon TR Brener ND 《Journal of American college health : J of ACH》2000,48(5):229-233
Suicide, the endpoint of a continuum that begins with suicide ideation, is the third leading cause of death among the US college-aged population. The first and second leading causes of death among this age group, unintentional injury and homicide, may also be linked to suicide ideation. We used data from the National College Health Risk Behavior Survey to examine the association between suicide ideation and injury-related behaviors among 18- to 24-year-old college students. Students who reported suicide ideation were significantly more likely than students who did not report considering suicide to carry a weapon, engage in a physical fight, boat or swim after drinking alcohol, ride with a driver who had been drinking alcohol, drive after drinking alcohol, and rarely or never used seat belts. Given this clustering of injury-related risk behaviors, college prevention programs should aim to reduce risks for injuries comprehensively, rather than addressing each risk behavior separately. 相似文献
993.
994.
Assessment of Airborne Exposure to Trihalomethanes from Tap Water in Residential Showers and Baths 总被引:4,自引:0,他引:4
This study evaluates airborne concentrations of common trihalomethane (THM) compounds in bathrooms during showering and bathing in homes supplied with chlorinated tap water. Three homes in an urban area were selected, each having three bedrooms, a full bath, and approximately 1,000 square feet of living area. THMs were concurrently measured in tap water and air in the shower/bath enclosure and the bathroom vanity area using Summa canisters. Chloroform (TCM), bromodichloromethane (BDCM), and chlorodibromomethane (CDBM) were quantified using U.S. Environmental Protection Agency (EPA) Method TO-14. Air samples were collected prior to, during, and after the water-use event for 16 shower and 7 bath events. Flow rate and temperature were measured, but not controlled. The increase in average airborne concentration (+/- standard error) during showers (expressed as microg/m3 in shower enclosure or bathroom air per microg/L in water) was 3.3+/-0.4 for TCM, 1.8+/-0.3 for BDCM, and 0.5+/-0.1 for CDBM (n = 12), and during baths was 1.2+/-0.4 for TCM, 0.59+/-0.21 for BDCM, and 0.15+/-0.05 for CDBM (n = 4). The relative contribution of each chemical to the airborne concentrations was consistent for all shower and bath events, with apparent release of TCM > BDCM > CDBM. The results are therefore consistent with their relative concentration in tap water and their vapor pressures. When the shower findings for TCM are normalized for water concentration, flow rate, shower volume, and duration, the average exposure concentrations in these urban residences are about 30% lower than those reported by other investigators using EPA analytical methods. This difference is likely attributable primarily to greater air exchange rates in residential shower/bath stalls compared to more "airtight" laboratory shower chambers. This appears to be the first field study to thoroughly evaluate THM exposures from residential showers and baths, and can be used to validate previously published models of tap water volatile chemical transfer to indoor air. 相似文献
995.
Isernhagen DD 《Work (Reading, Mass.)》2000,15(2):87-94
Effective and cost efficient work injury prevention and disability management requires an integrated process that involves a number of components. Each component needs to be linked into a continuum or system. Components by themselves will not provide satisfactory solutions. This article addresses some of the key components that need to be included in an effective work injury management system. The goals of a management system are discussed and how each component plays a part in achieving these goals. 相似文献
996.
Woolwine D 《Journal of homosexuality》2000,38(4):5-37
The three sociological conceptions of community are outlined: the imagined community, community as friendship, and community as local organizations or groups. The extent to which gay men in New York City experience a gay community in each of these ways is investigated by means of in-depth interviews. The type of moral discourse utilized by the gay men interviewed is also discussed. Finally, gay men in New York City are compared to the new Russian Jewish community in Brooklyn as to which is more "postmodern." 相似文献
997.
New product success is predictable. This paper highlights the findings of an extensive study into new product success and failure, and pinpoints what separates winners from losers. The key success factors are: product superiority—delivering unique benefits to customers, upfront homework—before development gets underway, sharp and early product definition, a strong market orientation with constant customer contact and input, and quality of execution of key activities in new product process. Sadly many firms and new product efforts are lacking on these success factors. This points to the need for a more disciplined approach to product development. One solution proposed is the implementation of a stage-gate or formal new product process—a blueprint for the process from idea to launch. A generic stage-gate is outlined in the article. The experiences of managers in firms which have implemented such processes are investigated, and the performance results are positive: improved teamwork, less recycle, higher success rates and shorter cycle times. 相似文献
998.
Siting Noxious Facilities: A Test of the Facility Siting Credo 总被引:2,自引:0,他引:2
Over the past decade it has become increasingly difficult to site noxious facilities, despite the fact that there is a growing need to do so. To address this problem, a set of guidelines for a fairer, wiser, and more workable siting process—the Facility Siting Credo—was developed during a National Facility Siting Workshop in 1990. This paper presents an empirical test of these guidelines. A questionnaire based on the Credo was completed by stakeholders in 29 waste facility siting cases, both successful and unsuccessful, across the United States and Canada. Using an independent determination of outcome (success), a preliminary ranking of the importance of various Credo principles was obtained. The data reveal that establishing trust between the developer and host community is an important factor in facilitating the siting process. The siting process is most likely to be successful when the community perceives the facility design to be appropriate and to satisfy its needs. Public participation also is seen to be an important process variable, particularly if it encourages a view that the facility best meets community needs. Moreover, a siting process where communities volunteer to host facilities is an approach that holds promise for meeting many of these key success criteria. 相似文献
999.
A Bayesian compound Poisson benefit-risk model is described in this paper, and used to evaluate recent revisions to the South Florida Building Code (SFBC). The model accounts for natural variability in hurricane frequency and severity, and uncertainty in the effectiveness of the revised code. Ranges of residential growth rate, code effectiveness, construction cost increase, and planning period length are assumed, to show the ranges of cost-to-performance ratio within which the code will make sense economically. The expected cost of residential hurricane damage over 50 years for ten South Florida counties assuming continuation of previous building practices was $93 billion, equivalent to the residential damage of 5.2 Andrews. Assuming a reduction in the growth of damageable housing in South Florida from 5.5% to 2% as a result of code revision, estimated damages under the new code were $45 billion. At a per-house construction cost increase of 5%, the probability of at least recovering the estimated $40 billion cost of the specified wind-resistant construction was estimated to be 47%. Expected return on investment was estimated at $7 billion over 50 years. The expected return lies between a $44 billion loss and a $47 billion gain, when growth in damageable housing is allowed to range from 1% to 4% and construction cost increases are assumed to lie between 3% and 8%. Actual monetary return for a 5% cost increase and 2% growth in damageable housing ranges from a $20 billion loss to a $100 billion gain with 95% probability, as a result of weather variability alone. Results support SFBC revisions on solely economic grounds, a conclusion strengthened considerably in light of potentially avoided deaths and hurricane traumas. The model represents one approach to evaluating economic aspects of the sustainability of new technological measures on the basis of available information. 相似文献
1000.
What Determines Trust in Information About Food-Related Risks? Underlying Psychological Constructs 总被引:12,自引:0,他引:12
Trust in risk information about food related-hazards may be an important determinant of public reactions to risk information. One of the central questions addressed by the risk communication literature is why some individuals and organizations are trusted as sources of risk information and others are not. Industry and government often lack public trust, whereas other sources (for example, consumer organizations, the quality media, medical doctors) are highly trusted. Problematically, previous surveys and questionnaire studies have utilized questions generated by the investigators themselves to assess public perceptions of trust in different sources. Furthermore, no account of the hazard domain was made. In the first study reported here, semistructured interviewing was used to elicit underpinning constructs determining trust and distrust in different sources providing food-related risk information ( n = 35). In the second study, the repertory grid method was used to elicit the terminology that respondents use to distinguish between different potential food-related information sources ( n = 35), the data being submitted to generalised Procrustes analysis. The results of the two studies were combined and validated in survey research ( n = 888) where factor analysis indicated that knowledge in itself does not lead to trust, but that trusted sources are seen to be characterised by multiple positive attributes. Contrary to previous research, complete freedom does not lead to trust—rather sources which possess moderate accountability are seen to be the most trusted. 相似文献