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911.
Anecdotal reports have suggested that the use and abuse of methamphetamine is increasing in the United States. To date, however, few scholarly works have explored the prevalence and correlates of methamphetamine use in the United States. To address this limitation, a secondary analysis was undertaken with data collected through the Arrestee Drug Abuse Monitoring (ADAM) Program. An examination of methamphetamine-positive rates among ADAM arrestees interviewed between 1991 and 2001 identified that its use is concentrated within the Western part of the United States. Supplementary analyses of Sacramento arrestees indicated that 71% were diagnosed as needing some form of alcohol or other drug treatment. Compared to those arrestees who were detected methamphetamine-negative, methamphetamine-positive arrestees in Sacramento were three times as likely to be white and to have been diagnosed in need of drug treatment. Implications for drug control policy are discussed. 相似文献
912.
Atila?Abdulkadiro?luEmail author Tayfun?S?nmez M. Utku?ünver 《Social Choice and Welfare》2004,22(3):515-538
A group of friends consider renting a house but they shall first agree on how to allocate its rooms and share the rent. We propose an auction mechanism for room assignment-rent division problems which mimics the market mechanism. Our auction mechanism is efficient, envy-free, individually-rational and it yields a non-negative price to each room whenever that is possible with envy-freeness.We would like to thank seminar participants at Barcelona, Boston College, Duke, Koç, Málaga, MIT, Michigan, NYU, conference participants at the First Brazilian Workshop of Game Theory Society (Sao Paulo 2002), SED 2002-Conference on Economic Design (New York City 2002), The Sixth International Meeting of the Society for Social Choice and Welfare (Pasadena 2002), an anonymous referee for their comments and Ahmet Alkan, Selçuk Karabati, Bari Tan, nsan Tunali for insightful discussions. Sönmez gratefully acknowledges the research support of KoçBank via the KoçBank scholar program and Turkish Academy of Sciences in the framework of the Young Scientist Award Program via grant TS/TÜBA-GEBP/2002-1-19. Any errors are our own responsibility. 相似文献
913.
This study examines demographic and situational factors in an effort to predict whether or not a complainant was injured, used resistance, experienced a completed assault, and whether charges were brought against the offender. If the accused had consumed alcohol or drugs, he was almost seven times more likely to be arrested. The complainant was six times more likely to report rape completion if she had consumed alcohol or drugs and if the complainant fell unconscious at any time during the attack she was significantly less likely to use a resistance strategy. The complainant's use of a compliance strategy at any time during the assault positively predicted not using a physical resistance strategy and sexual assault completion. The reporting of injury positively predicted use a physical resistance strategy and sexual assault completion. If the assault was completed, it was less likely that charges were pressed. Implications of these findings are discussed, and directions for future research are offered. 相似文献
914.
Is it more effective to reduce poverty among the elderly by increasing the benefits paid by the Supplemental Security Income (SSI) program or by increasing eligibility for the program? This paper answers that question from a policymaker's perspective. At given program cost levels, we compare the potential reduction in poverty from increasing benefit levels to the potential reduction associated with a variety of policy proposals that would increase eligibility for the program. This paper employs a microsimulation model containing an eligibility and benefits calculator, a participation model, and an optimization algorithm. The data are from the Survey of Income and Program Participation supplemented by the administrative records of the SSI program. The results show that increasing eligibility by relaxing the restrictions of the means tests can be more effective in reducing poverty than raising benefit levels. 相似文献
915.
916.
Circumstantial evidence places the p66 isoform of the adapter protein Shc in a position to mediate the accelerated aging phenotype displayed by mice expressing shortened forms of the tumor suppressor protein p53. We present a model in which p66(shc) may be responsible for integrating signals from the p53 pathway with signals from the insulin-like growth factor-1/Daf pathway in mammals. A full understanding of how interactions between p53 and p66(shc) affect longevity will require the production of animals with mutations in the genes encoding both proteins. 相似文献
917.
Restoring complex vegetation in urban settings: The case of tidal freshwater marshes 总被引:2,自引:0,他引:2
Andrew H. Baldwin 《Urban Ecosystems》2004,7(2):125-137
Tidal freshwater marshes have diverse plant communities that vary spatially and temporally due to hydrology, animal activity, and other factors. Development of urban centers along rivers of the U.S. Atlantic coast has reduced the historic extent and quality of these and other coastal wetlands. Because the vegetation of these wetlands is more complex than that of salt and brackish marshes (where restoration of vegetation typical of natural systems has sometimes been successful), restoration of tidal freshwater marsh vegetation is likely to be more difficult, particularly in urban areas. Watershed urbanization alters hydrology, sediment load, propagule availability and composition, nutrient status, and other variables that together create an environment different from that of wetlands in less developed areas, possibly precluding restoration of typical marsh vegetation. Tidal freshwater wetlands were historically extensive along the Anacostia River in Washington, DC, but most of these were lost due to filling, dredging, or hydrologic alteration. Over the last decade, the U.S. Army Corps of Engineers has implemented projects designed to restore tidal freshwater wetlands along the Anacostia, which involved increasing elevation with dredged river sediment and planting native vegetation. To illustrate some of the mechanisms affecting vegetation development in restored tidal freshwater marshes in urban areas, I present a case study on one of these wetlands, Kingman Marsh, that also includes research at another restored wetland and two natural reference sites. Studies by my research groups indicate that the restored wetlands undergo essentially a planting-modified process of primary succession. Low densities of seeds are initially present in the substrate, and prolific seed dispersal into the restored sites results in high initial plant diversity comprised of plantings and ruderal (i.e. weedy) natives and exotics. Seed banks develop rapidly at the restored sites, probably due to colonization and early reproduction by ruderal species. Hydrology and disturbance by non-native animals (including resident Canada goose) are important variables controlling establishment of vegetation in these systems. Recent literature and the case study indicate that the environmental conditions of urban settings impose constraints in restored wetlands that result in plant communities more like those of urban natural wetlands than those of wetlands in less urbanized watersheds. This suggests that rather than design wetland restoration projects with the goal of creating pristine wetland vegetation, restorationists must identify, accept, and if possible capitalize on the ecological constraints of the urban environment in setting achievable and desirable restoration goals. 相似文献
918.
Pollack WS 《New directions for youth development》2004,(103):17-30, table of contents
A continuing parent-youth bond throughout adolescence and young adulthood is the foundation for genuine emotional health, academic achievement, and healthy developmental trajectories and the antidote to youth violence. 相似文献
919.
Participation in organized out-of-school activities leads to long-term psychosocial and educational benefits for young people. Now we're learning which features of these activities best support individual children. 相似文献
920.
Tuma RS 《Science of aging knowledge environment : SAGE KE》2004,2004(4):nf11
NEW YORK CITY--Everyone has slow-witted moments: entering a room only to forget why, putting ice cream into the fridge, or blanking out on how to use the microwave. Some clinicians think that periodic mental lapses might help diagnose dementia with Lewy bodies (DLB), a scourge that kills brain cells (see DLB Case Study), although not all experts agree. Now, scientists have found that some cognitive blunders crop up more frequently in patients with DLB than in those with Alzheimer's disease (AD) or in healthy elderly individuals, according to work presented here on 15 January 2004 at an American Medical Association briefing for media. 相似文献