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The diagnosis of sudden infant death syndrome (SIDS) has been an enigma to medical examiners and coroners for decades. The recent drastic decrease in the number of SIDS cases has been associated with infants sleeping supine instead of prone. The apparent relation between sleeping position and SIDS has led to the marketing of several positioning sleep aids. We report a case of the improper use of one such device which resulted in the death of an infant.  相似文献   
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Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed.  相似文献   
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The purpose of this study was to evaluate the ability of two amphetamine class screening reagents to exclude ephedrine (EPH), pseudoephedrine (PSEPH), and phenylpropanolamine (PPA) from falsely producing positive immunoassay screening results. The study also sought to characterize the prevalence and concentration distributions of EPH, PSEPH, and PPA in samples that produced positive amphetamine screening results. Approximately 27,400 randomly collected human urine samples from Navy and Marine Corps members were simultaneously screened for amphetamines using the DRI and Abuscreen online immunoassays at a cutoff concentration of 500 ng/mL. All samples that screened positive were confirmed for amphetamine (AMP), methamphetamine (MTH), 3,4-Methylenedioxyamphetamine (MDA), 3,4-Methylenedioxymethamphetamine (MDMA), EPH, PSEPH, and PPA by gas chromatography/mass spectrometry (GC/MS). The DRI AMP immunoassay identified 1,104 presumptive amphetamine positive samples, of which only 1.99% confirmed positive for the presence of AMP, MTH, MDA, or MDMA. In contrast, the online AMP reagent identified 317 presumptive amphetamine positives with a confirmation rate for AMP, MTH, MDA, or MDMA of 7.94%. The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH. When compared to the entire screened sample set, PSEPH was present in approximately 3%, EPH in 0.9%, and PPA in 0.8% of the samples. The results indicate that cross reactivities for EPH, PSEPH, and PPA are greater than reported by the manufacturer of these reagents. The distribution of concentrations indicates that very large concentrations of EPH, PSEPH, and PPA are common.  相似文献   
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This study examines the association of self-perceptions with sixth to eighth graders' exposure to mixed-sex and dating contexts. It contrasts two hypotheses: the stress hypothesis, which suggests that the transition to romantic relationships will be associated with declines in self-esteem, especially for girls, and the leisure hypothesis, which suggests that movement into a desired role in an emotionally positive social context will be associated with positive emotions and higher self-esteem. Results indicate that adolescents experience mixed-sex settings positively, and that comfort with the other sex (for girls) and more time spent with the other sex (for boys) are predictive of more positive self-perceptions. Activity diary data suggest that these differences are due to differences in the emotional climate of same- and mixed-sex settings, rather than to the activities adolescents engage in with same- and mixed-sex groups. Dating boys who are less interested in dating experience lower self-esteem. Results are discussed in light of the transitional nature of mixed-sex relationships in early adolescence and the preparatory role played by same-sex friendships.  相似文献   
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A key goal of housing assistance programs is to help lower income households reach neighborhoods of opportunity. Studies have described the degree to which Low-Income Housing Tax Credit (LIHTC) developments are located in high-opportunity neighborhoods, but our focus is on how neighborhood outcomes vary across different subsets of LIHTC residents. We also examine whether LIHTC households are better able to reach certain types of neighborhood opportunities. Specifically, we use new data on LIHTC tenants in 12 states along with eight measures of neighborhood opportunity. We find that compared with other rental units, LIHTC units are located in neighborhoods with higher poverty rates, weaker labor markets, more polluted environments, and lower performing schools, but better transit access. We also find that compared with other LIHTC tenants, poor and minority tenants live in neighborhoods that are significantly more disadvantaged.  相似文献   
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Horn  Jörg 《Asia Europe Journal》2004,2(4):573-587
Federated micro-regions are constituent units of federations having a maximum population of 300,000. Many are ethnically based. Although not larger than cities, these 55 territories are, constitutionally speaking, equal entities of their federations and have in some instances even shaped their own foreign policy. This article provides an analysis of their ability to withstand structural constraints and take advantage of the opportunities which smallness offers. In the first part, it discusses problems related to economies of scale and identifies a trend to establish new rather than merge existing federated micro-regions. The second part highlights external relations activities of some federated micro-regions and explains their partly pragmatic, partly political motivation.  相似文献   
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