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OBJECTIVE: The objective of this study was to compare characteristics of smokers who did and did not report use of cessation aids as part of a tobacco control program in a military setting (n = 8994). DESIGN: The study is a longitudinal epidemiological study where the relationship between smoking status at follow-up and use of pharmacologic aids to quit smoking were assessed. MAIN OUTCOME MEASURES: Smoking cessation, post baseline use of cessation aids to quit smoking. RESULTS AND CONCLUSIONS: Individuals remaining abstinent were 70% less likely to have used NRT/pharmacological aids compared to those that relapsed. NRT/pharmacological aid users were more likely to report plans to smoke after military training, to have friends who smoke, and to accept a cigarette from a friend. NRT/pharmacological aid users were more likely to believe that using NRT was safer than smoking and to have engaged in harm reduction strategies. Our findings suggest that selection bias related to such characteristics may explain some of the discrepancies between effect sizes reported in efficacy compared to effectiveness studies of NRT and smoking outcomes currently reported in the literature.  相似文献   
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Basic research with pigeons on behavioral momentum suggests that differential reinforcement of alternative behavior (DRA) can increase the resistance of target behavior to change. This finding suggests that clinical applications of DRA may inadvertently increase the persistence of target behavior even as it decreases its frequency. We conducted three coordinated experiments to test whether DRA has persistence-strengthening effects on clinically significant target behavior and then tested the effectiveness of a possible solution to this problem in both a nonhuman and clinical study. Experiment 1 compared resistance to extinction following baseline rates of reinforcement versus higher DRA rates of reinforcement in a clinical study. Resistance to extinction was substantially greater following DRA. Experiment 2 tested a rat model of a possible solution to this problem. Training an alternative response in a context without reinforcement of the target response circumvented the persistence-strengthening effects of DRA. Experiment 3 translated the rat model into a novel clinical application of DRA. Training an alternative response with DRA in a separate context resulted in lower resistance to extinction than employing DRA in the context correlated with reinforcement of target behavior. The value of coordinated bidirectional translational research is discussed.  相似文献   
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It is unknown whether various types of obsessive-compulsive (OC) symptoms have a common genetic or environmental etiology. For example, it is unknown whether hoarding is etiologically associated with prototypic OC symptoms, such as washing, checking, and obsessing. Also unknown is whether particular OC-related symptoms are etiologically linked to the general tendency to experience emotional distress (negative emotionality). To investigate these and other issues, a community sample of 307 pairs of monozygotic and dizygotic adult twins provided scores on 6 OC-related symptoms (obsessing, neutralizing, checking, washing, ordering, and hoarding) and 2 markers of negative emotionality (trait anxiety and affective lability). Genetic factors accounted for 40%-56% of variance in the 8 phenotypic scores (M = 49% of variance for OC-related symptoms). Remaining variance was due to nonshared (person-specific) environment. More detailed analyses revealed a complex etiologic architecture, where OC-related symptoms arise from a mix of common and symptom-specific genetic and environmental factors. A general genetic factor was identified, which influenced all symptoms and negative emotionality. An environmental factor was identified that influenced all symptoms but did not influence negative emotionality. Each of the 6 types of symptoms was also shaped by its own set of symptom-specific genetic and environmental factors. The importance of genetic factors did not vary as a function of age or sex, and the architecture of general and specific etiologic factors was replicated for participants having relatively more severe OC symptoms. Gene-environment interactions were identified. Implications for an etiology-based classification system are discussed.  相似文献   
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Rachman's theory of fear acquisition proposes that directly-conditioned fears will differ from indirectly-conditioned fears in magnitude and anxiety response patterns, however the theory has received inconsistent empirical support. The aim of the present study was to describe the fear acquisition pathways for a community sample who reported driving-related fears, and to test Rachman's theory of fear acquisition. One hundred and ninety participants completed a questionnaire which assessed a variety of driving-related situations, reactions to motor vehicle accidents (MVAs), and anxiety response patterns. Professional psychological helpseeking and perceived need for treatment for driving-related fears were also assessed. Results failed to support Rachman's predictions. However, it was confirmed that respondents who had been involved in an MVA were more likely to ascribe their fears to a directly-conditioned pathway. The theoretical and methodological implications of the findings are discussed, along with suggestions for assessment of those with driving-related fears.  相似文献   
919.
In two experiments, 216 college students learned to solve one kind of mathematics problem before completing one of various practise schedules. In Experiment 1, students either massed 10 problems in a single session or distributed these 10 problems across two sessions separated by 1 week. The benefit of distributed practise was nil among students who were tested 1 week later but extremely large among students tested 4 weeks later. In Experiment 2, students completed three or nine practise problems in one session. The additional six problems constituted a strategy known as overlearning, but this extra effort had no effect on test scores 1 or 4 weeks later. Thus, long‐term retention was boosted by distributed practise and unaffected by overlearning. Unfortunately, most mathematics textbooks rely on a format that emphasises overlearning and minimises distributed practise. An easily adopted alternative format is advocated. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
920.
This study examines differences in the mentoring relationships of Asian American and Euro‐American college women. Findings showed that the groups view mentoring as equally important but that fewer Asians report having a mentor. However, those who have mentors find them to be just as valuable as do their Euro‐American counterparts. Este estudio examina las diferencias en las relaciones de mentoring de mujeres Asiáticas Americanas y Euro‐Americanas colegiales. Las conclusiones mostraron que los grupos ven mentoring como igualmente importante pero que menos Asiáticos informan teniendo un mentor. Sin embargo, los que tienen mentores los encuentran que ser apenas tan valioso como lo hacen sus contrapartes de Euro‐Americanos.  相似文献   
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