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201.
This study addresses a possible link between suicide and casino gambling. Resident suicide rates are analyzed for (a) a 1990 cross-section of 148 U.S. metropolitan areas and (b) before and after the advent of legalized casinos in five U.S. counties. Data are drawn from government and gaming industry sources. In cross-section, metro area suicide is strongly correlated with region, accidental death and homicide rates, age and race composition, and economic vitality, followed by a modest net positive correlation with casino presence. By contrast, the time series analysis yields no evidence of a gambling effect.  相似文献   
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This study examined (a) adolescent psychosocial risk factors for frequency (intensity) of marijuana use and for other illicit drug use among those who started using these drugs in early adulthood (adult initiators) and (b) the protective role of parent-adolescent relations in reducing or preventing drug use when adolescents enter early adulthood. The study's participants were male and female youth from a longitudinal prospective study. The participants' mean ages were 17 and 22 years at late adolescence and early adulthood, respectively. Independent measures assessed personality, parental, peer, and self-drug-use factors during late adolescence; dependent measures assessed frequency of marijuana use and other illicit drug use during early adulthood for initiators of the respective drug categories. The authors found that intensity of marijuana use was directly associated with the personality, parental, and self-drug-use domains and indirectly associated with the peer domain. Intensity of other illicit drug use was directly associated with personality and self-drug use. Analyses also revealed that some parent-adolescent relations factors buffered the effects of risk factors for both marijuana and other illicit drug-use intensity, whereas others enhanced the effects of protective factors against other illicit drug-use intensity. The results indicate that there are both commonalities and differences in precursors of marijuana and other illicit drug-use intensity among initiators of these drugs during early adulthood.  相似文献   
204.
An integrated analysis of the data from 3 different studies was conducted to examine the early psychosocial predictors of later marijuana use among adolescents. Longitudinal analysis of interview data was performed. The data used in the analysis were derived from (a) a sample of 739 predominantly White adolescents representative of the northeastern United States, (b) a sample of 1,190 minority adolescents from the East Harlem section of New York City, and (c) a sample of 1,374 Colombian adolescents from two cities in Colombia, South America. In 2 of the samples, participants were interviewed in their homes, and in the 3rd study, participants were assessed in school. The predictors included a number of variables from (a) the personality domain, reflecting the adolescents' conventionality and intrapsychic functioning; (b) the family domain, representing the parent-child mutual attachment relationship and parental substance use; (c) the peer domain, reflecting the peer group's delinquency and substance use; and (d) the adolescents' own use of legal drugs. The dependent variable was adolescent marijuana use. The results of the analysis demonstrated remarkable consistency in the risk and protective factors for later marijuana use across the 3 samples, attesting to the robust nature of these predictors and their generalizability across gender, time, location, and ethnic/cultural background. These findings have important implications for designing intervention programs. Programs aimed at preventing adolescent marijuana use can be designed to incorporate universal features and still incorporate specific components that address the unique needs of adolescents from different groups.  相似文献   
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Recent work has shown that correcting a dispositional inference may lead social observers to over‐emphasize the role of dispositional factors in subsequent judgments. This effect has been explained as a procedural rebound following a phase of dispositional suppression. We conducted two experiments to test an alternative explanation in terms of ego‐depletion. In Experiment 1, we compared the effects of ego‐depletion and dispositional rebound by relying on the attitude attribution paradigm and the cookie paradigm. In Experiment 2, we turned to a difficult math task in order to induce fatigue. We were able to replicate the dispositional rebound and the ego‐depletion effects but none of the experiments supported an ego‐depletion explanation of post‐suppression dispositional rebound. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
206.
In area CA1 of hippocampal slices, a single 1-sec train of 100-Hz stimulation generally triggers a short-lasting long-term potentiation (S-LTP) of 1–2 h. Here, we found that when such a train was applied 45 min after application of the small conductance Ca2+-activated K+ (SK) channel blocker apamin, it induced a long-lasting LTP (L-LTP) of several hours, instead of an S-LTP. Apamin-induced SK channel blockage is known to resist washing. Nevertheless, the aforementioned effect is not a mere delayed effect; it is metaplastic. Indeed, when a single train was delivered to the Schaffer’s collaterals during apamin application, it induced an S-LTP, like in the control situation. At the moment of this LTP induction (15th min of apamin application), the SK channel blockage was nevertheless complete. Indeed, at that time, under the influence of apamin, the amplitude of the series of field excitatory postsynaptic potentials (fEPSPs) triggered by a stimulation train was increased. We found that the metaplastic effect of apamin on LTP was crucially dependent on the NO-synthase pathway, whereas the efficacy of the NMDA receptors was not modified at the time of its occurrence. We also found that apamin produced an increase in paired-pulse facilitation not during, but after, the application of the drug. Finally, we found that the induction of each of these two metaplastic phenomena was mediated by NMDA receptors. A speculative unitary hypothesis to explain these phenomena is proposed.  相似文献   
207.
This study tested the prospective effects of hope on depression and anxiety using a longitudinal design. A sample of 522 college students completed self-report measures of hope, depression, and anxiety at three time points, with 1-month delays between administrations. Structural equation modeling was employed to test two cross-lagged panel models of the reciprocal effects of the Agency and Pathways components of hope on depression and anxiety. Results indicated statistically significant negative effects for the Agency component of hope on later depression but no unique effect of the Pathways component of hope on depression. Likewise, Agency showed a statistically significant negative effect on later anxiety, but again Pathways had no significant influence on anxiety. In both cases, neither depression nor anxiety demonstrated any longitudinal effects on either the Agency or Pathways components of hope. Implications of these findings are discussed, along with potential directions for future research.  相似文献   
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Decades of research has shown that example-based learning is an effective instructional strategy for learning new skills. The field of learning from examples is seeing a shift in focus towards more innovative and use-inspired research, in part because the use of examples for informal and formal learning purposes has mushroomed. This special issue comprises a set of eight papers in which students learned a procedural skill from worked examples or modeling examples. Each study characterizes a recent development towards more innovative example-based learning research. These developments are: (a) the integration of social-cognitive and cognitive example research, (b) the integration of example-based learning and analogical reasoning research, (c) the extension of traditional Cognitive Load Theory effects, (d) a greater focus on learning from (productive) errors, and (e) more research on individual differences. This special issue concludes with insightful commentary articles written by Prof. Dr. Katharina Scheiter and Prof. Dr. Richard Mayer.  相似文献   
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