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91.
92.
Jungeun Olivia Lee Junhan Cho Yoewon Yoon Mariel S. Bello Rubin Khoddam Adam M. Leventhal 《Journal of youth and adolescence》2018,47(2):334-348
Although lower socioeconomic status has been linked to increased youth substance use, much less research has determined potential mechanisms explaining the association. The current longitudinal study tested whether alternative (i.e., pleasure gained from activities without any concurrent use of substances) and complementary (i.e., pleasure gained from activities in tandem with substance use) reinforcement mediate the link between lower socioeconomic status and youth substance use. Further, we tested whether alternative and complementary reinforcement and youth substance use gradually unfold over time and then intersect with one another in a cascading manner. Potential sex differences are also examined. Data were drawn from a longitudinal survey of substance use and mental health among high school students in Los Angeles. Data collection involved four semiannual assessment waves beginning in fall 2013 (N?=?3395; M baseline age?=?14.1; 47% Hispanic, 16.2% Asian, 16.1% multiethnic, 15.7% White, and 5% Black; 53.4% female). The results from a negative binomial path model suggested that lower parental socioeconomic status (i.e., lower parental education) was significantly related to an increased number of substances used by youth. The final path model revealed that the inverse association was statistically mediated by adolescents’ diminished engagement in pleasurable substance-free activities (i.e., alternative reinforcers) and elevated engagement in pleasurable activities paired with substance use (i.e., complementary reinforcers). The direct effect of lower parental education on adolescent substance use was not statistically significant after accounting for the hypothesized mediating mechanisms. No sex differences were detected. Increasing access to and engagement in pleasant activities of high quality that do not need a reinforcement enhancer, such as substances, may be useful in interrupting the link between lower parental socioeconomic status and youth substance use. 相似文献
93.
Activated protein C resistance (APC-R) is the most common inherited defect of the coagulation system known to date, affecting 3-5% of Americans. It is an autosomal dominant disorder associated with an increased risk of venous thrombosis and is reportedly found in 21% of individuals with deep venous thrombosis. Medical examiners are in a unique position to make the diagnosis since a fatal pulmonary embolism may be the first manifestation of the disorder. This study examines the prevalence of APC-R in individuals who die suddenly of pulmonary embolism to help medical examiners decide if routine testing is indicated. We examined 66 cases of sudden death due to pulmonary embolism seen at the Bexar County Forensic Science Center in San Antonio, Texas, from 1993-1997. The median age was 46 years with a range of 14 to 93 years. Fifty-three percent were Caucasian, 24% were African-American, and 23% were Hispanic. Twenty-seven percent had no known risk factors for pulmonary embolism. Whole blood was tested for the factor V codon 506Q mutation responsible for APC-R using polymerase chain reaction. The prevalence of APC-R was 4.5%, which is similar to the prevalence of APC-R in the general American population. These data imply that individuals with APC-R are not in increased risk for sudden death due to pulmonary embolism, or, conversely, that most fatal pulmonary emboli seen in the medical examiner setting are not induced by APC-R. Routine postmortem testing for the factor V 506Q mutation does not appear indicated at this time, given the low prevalence and high cost of testing. 相似文献
94.
Sungwook Hong Ph.D. Jae‐Hee Park M.Sc. Ju‐Hee Park M.Sc. Han‐byeol Oh M.Sc. Eun‐Ju Choi M.Sc. Il‐Han Cho M.Sc. Yoon‐Jung Mok M.Sc. 《Journal of forensic sciences》2019,64(4):1040-1047
Latent fingermark developing methods from food (mandarin, egg, banana, apple, potato, carrot, eggplant, onion, bell pepper, and tomato) surface has been studied by 10 methods, including powdering method, small particle reagent method, and cyanoacrylate fuming method. The foods were stored under two conditions (room temperature and refrigerator) before fingermark deposition and aged for 2, 24, 48, and 72 h before fingermark development. In most of the food surfaces used in this study, cyanoacrylate fuming with 80% relative humidity was superior to the powder or small particle reagent methods. The quality of the fingermarks varied depending on the storage conditions before the fingermark deposition (in the refrigerator or at ambient temperature) and the time elapsed since the fingermark deposition. However, the storage conditions before the fingermark deposition and the time elapsed since the fingermark deposition did not show any correlation with the quality of the fingermark. 相似文献
95.
Asian Journal of Criminology - Numerous studies have analyzed the relationship between disorder and fear of crime, but few have focused on the impact of policing against disorder on fear of crime.... 相似文献
97.
The use of racial categories in biomedicine has had a long history in the United States. However, social hierarchy and discrimination, justified by purported scientific differences, has also plagued the history of racial categories. Because "race" has some correlation with biological and genetic characteristics, there has been a call not to "throw the baby out with the bathwater" by eliminating race as a research or clinical category. I argue that race is too undefined and fluid to be useful as a proxy for biology or genetics. 相似文献
98.
After 20 months of interment in a deep grave, the decomposed body of the 81-year old testator of a will was exhumed to sustain the burden of proof that he lacked testamentary capacity when the will was rewritten two days prior to his death. The brain was mushy and pulverized with complete disappearance of the brainstem, cerebellum and subcortical ganglia. Small foci of relatively intact dorsal frontal neocortex were identified. Sections from these foci were stained with hematoxylin and eosin, bielchowsky silver stain and immunostains for beta amyloid peptide (betaA4), tau and alpha-synuclein. Despite severe autolysis and decomposition, the bielchowsky stain and the betaA4 immunostains showed preserved frequent neuritic amyloid plaques with very few residual neurofibrillary tangles. Cerebral Amyloid Angiopathy was present. At the present time this case represents the first documented and reported case of direct tissue diagnosis of Alzheimer's Disease pathology in a decomposed brain following long term burial in a deep grave. 相似文献
99.
Spatial Effects and Ecological Inference 总被引:1,自引:0,他引:1
This paper examines the role of spatial effects in ecologicalinference. Both formally and through simulation experiments,we consider the problems associated with ecological inferenceand cross-level inference methods in the presence of increasingdegrees of spatial autocorrelation. Past assessments of spatialautocorrelation in aggregate data analysis focused on unidimensional,one-directional processes that are not representative of thefull complexities caused by spatial autocorrelation. Our analysisis more complete and representative of true forms of spatialautocorrelation and pays particular attention to the specificationof spatial autocorrelation in models with random coefficientvariation. Our assessment focuses on the effects of this specificationon the bias and precision of parameter estimates. 相似文献
100.
Three complementary methods in the order of stereomicroscopy, micro-FT-IR spectroscopy and solubility tests were used for the purpose of matching known and questioned paint samples in an auto accident case. Grayish green paint smears scattered on a silvery gray coated plastic bar were taken from a blue car and referred to as questioned samples. Green paint chips were collected as known samples from a green car. These were analyzed to determine whether the paint smears found in the blue car could have been the transfers from the green car. Although each of the three methods, when used alone, suffered from unequal bases for making comparison (i.e., layering whole paint vs. smeared paint), insufficient specificity of methodology and the interfering background coating beneath the smeared paint, the limitations were significantly relieved when three methods were used in combination. Based on the results presented in this report, the questioned grayish green paint smears collected from the blue car and the known green paint chips from the green car are of the same class of paint; that is, the possibility of the above stated paint transfers cannot be eliminated. 相似文献