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Mallak CT Milch KS Horn DF 《The American journal of forensic medicine and pathology》2000,21(1):79-82
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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Renita?R.?Glaser M.?Lee?Van.?Horn Michael?W.?ArthurEmail author J.?David.?Hawkins Richard?F.?Catalano 《Journal of Quantitative Criminology》2005,21(1):73-102
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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Darling Nancy Dowdy Bonnie B. Van Horn M. Lee Caldwell Linda L. 《Journal of youth and adolescence》1999,28(4):461-480
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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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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Dr. Dean A. Horn 《The Journal of Technology Transfer》1982,6(2):1-7
A network of 29 Sea Grant Programs now operate in almost all of the 34 eligible coastal and Great Lake states, the Commonwealth of Puerto Rico, and the U.S. Island Territories. Operating in response to current needs and opportunities by applying faculty, research staff and student expertise, Sea Grant Programs have developed many new systems, processes, policy and legal studies, and technologies. These have been effectively transferred to user groups, including major industries, businesses, government agencies, citizen groups and individuals. Many examples of successful technology development and transfer are discussed. Some examples are the hydrodynamic modeling of transport and dispersion of pollutants in large definable water bodies, the demonstration of a prototype machine for skinning the Spiny Dogfish Shark and application of vibration studies to reduce wave response of offshore structures. The examples demonstrate the viability and effectiveness of the Sea Grant concept. 相似文献
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Why Don't Housing Choice Voucher Recipients Live Near Better Schools? Insights from Big Data
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Ingrid Gould Ellen Keren Mertens Horn Amy Ellen Schwartz 《Journal of policy analysis and management》2016,35(4):884-905
Housing choice vouchers provide low‐income households with additional income to spend on rental housing in the private market. The assistance vouchers provide is substantial, offering the potential to dramatically expand the neighborhoods—and associated public schools—that low‐income households can reach. However, existing research on the program suggests that housing choice voucher holders live in neighborhoods with schools that are no better than those accessible to other households with similar incomes. Households, in other words, do not seem to spend the additional income provided by the voucher to access better schools. In this analysis we rely on a large‐scale administrative data set to explore why voucher households typically do not live near to better schools, as measured by school‐level proficiency rates. We combine confidential administrative data from the Department of Housing and Urban Development on 1.4 million housing choice voucher holders in 15 states, with school‐level data from 5,841 different school districts, to examine why the average housing voucher holder does not live near to higher‐performing schools than otherwise similar households without vouchers. Specifically, we use the large‐scale administrative data set to test whether voucher holders living in areas with good schools nearby and slack housing markets move toward better schools when schools become salient for them—that is, when their oldest child becomes school eligible. We take advantage of the thick sample of households with young children provided through our administrative data to implement both a household fixed effects and a regression discontinuity design. Together these analyses shed light on whether voucher households are more likely to move toward better schools when schools are most relevant, and how market conditions shape that response. We find that families with vouchers are more likely to move toward a better school in the year before their oldest child meets the eligibility cutoff for kindergarten, suggesting salience matters. Further, the magnitude of the effect is larger in metropolitan areas with a relatively high share of affordable rental units located near high‐performing schools and in neighborhoods in close proximity to higher‐performing schools. Results suggest that, if given the appropriate information and opportunities, more voucher families would move to better schools when their children reach school age. 相似文献