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501.
OBJECTIVE: Smoking has been linked to disease and injury. The purpose of this study is to investigate the smoking habits of motor vehicular driver trauma center patients and their association with previous injury history and risky behaviors. METHODS: The studied population included 323 motor vehicular driver injury patients (123 smokers and 200 non-smokers) interviewed as part of a larger study of psychoactive substance use disorders at an adult Level I trauma center. Patients with head injuries, hospital stays of less than two days, and diminished cognition were excluded. Interviews included demographics (age, gender, race, marital status), socioeconomic status (SES; income, education, employment), risky behaviors (seatbelt non-use, drinking and driving, riding with drunk driver, binge drinking), and trauma history information (vehicular, assault, and other injuries). Substance abuse (alcohol and drug dependence) was evaluated in depth using DSM III-R criteria. Smokers and non-smokers were compared in relation to control and dependent variables using student's t test and chi-square (alpha = 0.05). Outcome variables included previous trauma history and risky behaviors. Multiple logistic regression models using step-down selection methods (alpha = 0.05) were constructed with risky behaviors and trauma history as dependent variables including demographics, SES and substance as independent variables. RESULTS: Smokers represented 38 percent of the 323 patients studied. Smokers (n = 123) were younger (34 vs. 43 years), more likely to be male (72 percent vs. 50 percent), not married (72 percent vs. 56 percent), and had higher rates of alcohol (29 percent vs. 9 percent) and drug dependence (14 percent vs. 3 percent) than non-smokers (n = 200). Educational achievement (20 percent vs. 15 percent less than high school) and income level (24 percent vs. 23 percent with less than $15,000 of yearly income) were not different between smokers and non-smokers. Smokers were more likely than non-smokers to have a history of prior vehicular trauma (48 percent vs. 26 percent), assault (25 percent vs. 9 percent), or other injury (50 percent vs 37 percent). The following injury-prone behaviors were also more common among the smokers than non-smokers: seatbelt non-use (49 percent vs. 29 percent), drinking and driving (38 percent vs. 15 percent), riding with drunk driver (38 percent vs. 13 percent), and binge drinking (68 percent vs. 26 percent). In multiple logistic regression models adjusting for demographics, SES, and substance abuse, smoking revealed significantly higher odds ratios (OR) for the following dependent variables: seatbelt non-use (OR = 2.9), riding with drunk driver (OR = 2.2), binge drinking (OR = 2.4), previous vehicular (OR = 2.0), and assault injuries (OR = 2.5). Smoking did not reach significance for drinking and driving and other (non-vehicular and non-assault) injury. CONCLUSION: Smoking is independently associated with risky behaviors and repeated history of vehicular or assault injury within the vehicular trauma population.  相似文献   
502.
The 2010 Deepwater Horizon (DWH) oil spill exposed common bottlenose dolphins (Tursiops truncatus) in Barataria Bay, Louisiana to heavy oiling that caused increased mortality and chronic disease and impaired reproduction in surviving dolphins. We conducted photographic surveys and veterinary assessments in the decade following the spill. We assigned a prognostic score (good, fair, guarded, poor, or grave) for each dolphin to provide a single integrated indicator of overall health, and we examined temporal trends in prognostic scores. We used expert elicitation to quantify the implications of trends for the proportion of the dolphins that would recover within their lifetime. We integrated expert elicitation, along with other new information, in a population dynamics model to predict the effects of observed health trends on demography. We compared the resulting population trajectory with that predicted under baseline (no spill) conditions. Disease conditions persisted and have recently worsened in dolphins that were presumably exposed to DWH oil: 78% of those assessed in 2018 had a guarded, poor, or grave prognosis. Dolphins born after the spill were in better health. We estimated that the population declined by 45% (95% CI 14–74) relative to baseline and will take 35 years (95% CI 18–67) to recover to 95% of baseline numbers. The sum of annual differences between baseline and injured population sizes (i.e., the lost cetacean years) was 30,993 (95% CI 6607–94,148). The population is currently at a minimum point in its recovery trajectory and is vulnerable to emerging threats, including planned ecosystem restoration efforts that are likely to be detrimental to the dolphins’ survival. Our modeling framework demonstrates an approach for integrating different sources and types of data, highlights the utility of expert elicitation for indeterminable input parameters, and emphasizes the importance of considering and monitoring long-term health of long-lived species subject to environmental disasters. Article impact statement: Oil spills can have long-term consequences for the health of long-lived species; thus, effective restoration and monitoring are needed.  相似文献   
503.
Unsustainable exploitation of wild species represents a serious threat to biodiversity and to the livelihoods of local communities and Indigenous peoples. However, managed, sustainable use has the potential to forestall extinctions, aid recovery, and meet human needs. We analyzed species-level data for 30,923 species from 13 taxonomic groups on the International Union for Conservation of Nature Red List of Threatened Species to investigate patterns of intentional biological resource use. Forty percent of species (10,098 of 25,009 species from 10 data-sufficient taxonomic groups) were used. The main purposes of use were pets, display animals, horticulture, and human consumption. Intentional use is currently contributing to elevated extinction risk for 28–29% of threatened or near threatened (NT) species (2752–2848 of 9753 species). Intentional use also affected 16% of all species used (1597–1631 of 10,098). However, 72% of used species (7291 of 10,098) were least concern, of which nearly half (3469) also had stable or improving population trends. The remainder were not documented as threatened by biological resource use, including at least 172 threatened or NT species with stable or improving populations. About one-third of species that had use documented as a threat had no targeted species management actions to directly address this threat. To improve use-related red-list data, we suggest small amendments to the relevant classification schemes and required supporting documentation. Our findings on the prevalence of sustainable and unsustainable use, and variation across taxa, can inform international policy making, including the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, the Convention on Biological Diversity, and the Convention on International Trade in Endangered Species.  相似文献   
504.
505.
Assessment of irrigation water quality. A proposal of a quality profile   总被引:1,自引:0,他引:1  
Water quality indices provide a simple and understandable tool for managers on the quality and possible uses for irrigation water, however an individual quality factor alone is not enough to evaluate the irrigation water quality because it could be restrictive and sometime it could give an unfavorable qualification. The aim of this paper was propose a quality profile of irrigation water using the preexisting water quality indices to be applied to arid and semi-arid regions. As a case studied, the water of the Del Molle River (Nogolí, San Luis, Argentina) was researched. Samples were collected during the period October 2005-May 2006. Conductivity, pH, total hardness, sulphate, nitrate, nitrite, alkalinity, chloride, sodium, potassium, TDS, DO and phosphate were analyzed. The irrigation water quality, according to Riverside Norm, belongs to C(2)-S(1) class, according to Wilcox Norm as excellent to good, according to Scott quality factor it is good and according to SAR < 10 and according to RCS it is recommendable. From the obtained data, it can be concluded that the water quality profile was good, so it is useful for normal irrigation agriculture.  相似文献   
506.
PROBLEM: To assess effects of the 1999 Maryland graduated driver licensing (GDL) law on both 16-year-old drivers and other road users. METHOD: Calculation and comparison of crash involvement rates and non-fatal injury rates pre-GDL (1996-1998) and post-GDL (2001-2003) by type of road user, per population, and per licensed driver, with adjustment for trends among 30-59-year-old drivers. RESULTS: Post-GDL, prevalence of licensure decreased 24% among 16-year-olds, and rates of 16-year-old drivers involved in crashes significantly decreased per 16-year-old population (corrected rate ratio (RRc) 0.82; 95% CI (0.71, 0.96)). A significant decrease also was observed for non-fatal injuries per 16-year-old population among 16-year-old drivers involved in crashes (RRc 0.63; 95% CI (0.41, 0.98)). Similarly, decreases, albeit not statistically significant, were observed among their passengers and other vehicle occupants. Per 16-year-old licensed driver, a slight non-significant increase was observed in crash involvement rates; non-fatal injury rates per 16-year-old licensed driver suggest decreased risk (non-significant) among 16-year-old drivers, their passengers, and other vehicle occupants. SUMMARY: Maryland's GDL delayed licensure and reduced crashes and non-fatal injuries among 16-year-old drivers per population. Trends in injuries among other road users involved in crashes with 16-year-old drivers were suggestive of a benefit from GDL, although observed decreases were not significant. Per licensed driver, findings were not significant, but suggested little change in crash involvement and decreased non-fatal injuries. Because one-third fewer 16-year-olds were licensed post-GDL, these results may suggest a selection effect in licensure. IMPACT ON INDUSTRY: Because Maryland had nighttime restrictions for new drivers before 1999, this study suggests other components of GDL are beneficial for drivers and possibly for other road users. States with weak GDL laws should strongly consider revising them.  相似文献   
507.
The "choking game" is defined as self-strangulation or strangulation by another person with the hands or a noose to achieve a brief euphoric state caused by cerebral hypoxia. Participants in this activity typically are youths (Andrew & Fallon, 2007). Serious neurologic injury or death can result from engaging in this activity. Recent news media reports have described numerous deaths among youths attributed to the choking game. Because no traditional public health dataset collects data on this practice, CDC used news media reports to estimate the incidence of deaths from the choking game. This report describes the results of that analysis, which identified 82 probable choking-game deaths among youths aged 6-19 years during 1995-2007. Seventy-one (86.6%) of the decedents were male, and the mean age was 13.3 years. Parents, educators, and health-care providers should become familiar with warning signs that youths are playing the choking game (Urkin & Merrick, 2006). Impact of industry: By learning about the risk factors for and warning signs of the choking game, parents, educators, and health-care providers may be able to identify youth at risk for playing the game and prevent future deaths.  相似文献   
508.
This study tested a relational demography model of workgroup identification. We theorized that early in workgroup formation, (a) racial identification would moderate the influence of racial dissimilarity on member communication behavior (frequency and length of verbal participation) during a group task, (b) member communication behaviors would mediate the effect of racial dissimilarity on workgroup identification, and that (c) these effects would be affected non‐symmetrically by racial group membership (White, Black). This model was tested among a sample of 211 undergraduates (113 White and 98 Black), working in 43 temporary workgroups. Whites' racial identification moderated the relationship between racial dissimilarity and member communication behaviors, which in turn partially mediated the effect of racial dissimilarity on workgroup identification, generally consistent with our model. Among Black workgroup members support for our model was limited. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
509.
Regionalization frameworks cluster geographic data to create contiguous regions of similar climate, geology and hydrology by delineating land into discrete regions, such as ecoregions or watersheds, often at several spatial scales. Although most regionalization schemes were not originally designed for aquatic ecosystem classification or management, they are often used for such purposes, with surprisingly few explicit tests of the relative ability of different regionalization frameworks to group lakes for water quality monitoring and assessment. We examined which of 11 different lake grouping schemes at two spatial scales best captures the maximum amount of variation in water quality among regions for total nutrients, water clarity, chlorophyll, overall trophic state, and alkalinity in 479 lakes in Michigan (USA). We conducted analyses on two data sets: one that included all lakes and one that included only minimally disturbed lakes. Using hierarchical linear models that partitioned total variance into within-region and among-region components, we found that ecological drainage units and 8-digit hydrologic units most consistently captured among-region heterogeneity at their respective spatial scales using all lakes (variation among lake groups = 3% to 50% and 12% to 52%, respectively). However, regionalization schemes capture less among-region variance for minimally disturbed lakes. Diagnostics of spatial autocorrelation provided insight into the relative performance of regionalization frameworks but also demonstrated that region size is only partly responsible for capturing variation among lakes. These results suggest that regionalization schemes can provide useful frameworks for lake water quality assessment and monitoring but that we must identify the appropriate spatial scale for the questions being asked, the type of management applied, and the metrics being assessed.  相似文献   
510.
We consider the extent to which the Mackenzie Valley Resource Management Act (MVRMA) provides an opportunity for deliberative democracy to emerge within the context of resource management in Canada's North. The focus is on the extent to which the tenets of deliberative democracy are exercised in the environmental assessment (EA) of the Snap Lake diamonds project. Data collection included semi-structured interviews with assessment participants, and a review of documentation surrounding the EA process, and the case study. Results combined four principles of deliberative democracy: generality, autonomy, power neutrality, and ideal role taking. The EA conducted under the MVRMA can serve as a deliberative process, as illustrated by opportunities for dialogue, access to different perspectives, and learning outcomes. However, many of these positive results occurred through nonmandated technical sessions. The absence of participant funding also limits the deliberative potential of the MVRMA.  相似文献   
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