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191.
We have previously shown that fear extinction is accompanied by an increase of synaptic efficacy in inputs from the ventral hippocampus (vHPC) and mediodorsal thalamus (MD) to the medial prefrontal cortex (mPFC) and that disrupting these changes to mPFC synaptic transmission compromises extinction processes. The aim of this study was to examine whether these extinction-related changes undergo further plasticity as the memory of extinction becomes more remote. Changes in synaptic efficacy in both vHPC-mPFC and MD-mPFC inputs were consequently analyzed when the memory was either 1 d or 7 d old. Increases of synaptic efficacy in the vHPC-mPFC pathway were observed when the memory was 1 d old, but not 7 d after initial extinction. In contrast, potentiation of synaptic efficacy in the MD-mPFC pathway increased over time. In rats that received low-frequency vHPC stimulation immediately after extinction, both vHPC-mPFC and MD-mPFC inputs failed to develop potentiation, and the recall of extinction (both recent and remote memories) was impaired. These findings suggest that post-extinction potentiation in vHPC-mPFC inputs may be necessary for both the recall of recent memory and post-extinction potentiation in the MD-mPFC inputs. This late potentiation process may be required for the recall of remote extinction memory.  相似文献   
192.
This article presents the initial findings of a research project funded by the Leverhulme Trust from 2003 to 2005. It should be seen as the sequel to a pilot study originally conducted in 2002 and published in the Journal of Contemporary Religion in 2003 (Molokotos-Liederman, ”Identity Crisis“). The article examines the ID card controversy in Greece, setting it in its broader European context. Using data from newspaper articles and interviews, it maps the different opinion groups that emerge from this controversy and offers a preliminary analysis of these views. The final section indicates a range of topics that are emerging from this study and merit further investigation.  相似文献   
193.
The main objective of this study is to report rated age of acquisition (AoA) norms for 834 nouns in Portuguese (European). AoA ratings were collected on a 7 point scale, generally following Gilhooly and Logie (1980) procedure with an 8 extra point for "don't know the word" answers. Results were analyzed considering AoA ratings and their standard deviations and considering the relationship between AoA ratings and other psycholinguistic variables (imageability, familiarity, written word frequency, concreteness, number of syllables and number of words). AoA ratings and their standard deviations were significantly and positively correlated, with early acquired word ratings showing higher agreement. Correlation and multiple regression analyses confirmed the major contribution of imageability and familiarity to AoA ratings obtained in other languages. The full database of AoA ratings and other psycholinguistic variables may be downloaded from www.psychonomic.org/archive or www.fpce.ul.pt/pessoal/ulfpfred/aoa.htm.  相似文献   
194.
OBJECTIVE: Given that only 25% of Americans meet physical activity recommendations, there is a need to develop and disseminate effective, evidence-based interventions to promote physical activity. The authors tested 2 delivery channels, telephone and print, to determine whether one was more effective in promoting physical activity. DESIGN: The authors randomly assigned 239 healthy, sedentary adults to (a) telephone-based individualized feedback, (b) print-based individualized feedback, or (c) contact control. Both intervention arms were guided by a motivationally tailored, theoretically driven computer expert system. MAIN OUTCOME MEASURES: Physical activity as measured by the 7-day Physical Activity Recall interview. RESULTS: At 6 months, both telephone and print arms significantly increased in minutes of moderate intensity physical activity compared with control, with no differences between the intervention arms. At 12 months, print participants reported a significantly greater number of moderate intensity minutes than both telephone and control participants, who did not differ. CONCLUSION: Results suggest that both telephone and print enhance the adoption of physical activity among sedentary adults; however, print interventions may be particularly effective in maintaining physical activity in the longer term.  相似文献   
195.
Guided by the Career Construction Theory (Savickas, 2013), we view entrepreneurship as an adaptive vocational behavior driven by an individual's self-regulatory capacity to thrive in a complex entrepreneurial career context. Our research model posited that individuals rely on their adaptive resources and entrepreneurial self-efficacy as they form entrepreneurial intentions. Career adaptability, as self-regulatory competencies, is further strengthened by prior exposure to family business. We collected data over three measurement periods from Serbian business students (n = 380) and validated the Career Adapt-Abilities Scale (CAAS). The moderated mediation model was supported and as predicted: (a) career adaptability was positively associated with entrepreneurial intentions and (b) the mediated relationship between career adaptability and entrepreneurial intentions via entrepreneurial self-efficacy was stronger for individuals with prior exposure to family business. In addition, we provide evidence for the psychometric properties of CAAS by examining its internal consistency, test–retest reliability, and factor structure. Taken together, our study offers the groundwork for understanding successful adaptation in the entrepreneurial career context and supports the cross-national measurement equivalence and utility of CAAS in a developing economy.  相似文献   
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It is estimated that the percentage of students using illicit substances by sixth grade has tripled over the last decade not only in developed countries but in developing countries as well probably due to the transition to a more Western society. Although much has been done to understand the mechanisms underlying substance abuse, few studies have been conducted with minority ethnic and religious groups such as Middle Eastern Youth. The primary goal of this study was to determine whether there are differences in factors contributing to substance abuse in adolescents from Lebanon versus the USA and to decipher the role of spirituality, religion, and culture among other factors that may influence substance abuse. A correlational cross-sectional design was used with adolescents living in two different countries: Los Angeles, California and Beirut, Lebanon. Muslim adolescents had significantly less rates of alcohol and substance use than Christians in both Lebanon and Los Angeles. More years lived in the USA increases the likelihood of abuse for both Muslims and Christians. Attachment to God and family was negatively associated with substance abuse. These results among others facilitate a better understanding of the influence of culture, religion, family and personal factors on substance abuse. Culturally sensitive interventions could benefit from the findings of this pilot study.  相似文献   
199.
Both shared and unique genetic risk factors underlie the two symptom domains of attention deficit hyperactivity disorder (ADHD): inattention and hyperactivity-impulsivity. The developmental course and relationship to co-occurring disorders differs across the two symptom domains, highlighting the importance of their partially distinct etiologies. Familial cognitive impairment factors have been identified in ADHD, but whether they show specificity in relation to the two ADHD symptom domains remains poorly understood. We aimed to investigate whether different cognitive impairments are genetically linked to the ADHD symptom domains of inattention versus hyperactivity-impulsivity. We conducted multivariate genetic model fitting analyses on ADHD symptom scores and cognitive data, from go/no-go and fast tasks, collected on a population twin sample of 1,312 children aged 7–10. Reaction time variability (RTV) showed substantial genetic overlap with inattention, as observed in an additive genetic correlation of 0.64, compared to an additive genetic correlation of 0.31 with hyperactivity-impulsivity. Commission errors (CE) showed low additive genetic correlations with both hyperactivity-impulsivity and inattention (genetic correlations of 0.17 and 0.11, respectively). The additive genetic correlation between RTV and CE was also low and non-significant at ?0.10, consistent with the etiological separation between the two indices of cognitive impairments. Overall, two key cognitive impairments phenotypically associated with ADHD symptoms, captured by RTV and CE, showed different genetic relationships to the two ADHD symptom domains. The findings extend a previous model of two familial cognitive impairment factors in combined subtype ADHD by separating pathways underlying inattention and hyperactivity-impulsivity symptoms.  相似文献   
200.
We conducted two experiments to evaluate the effects of errors of omission and commission during alternative reinforcement of compliance in young children. In Experiment 1, we evaluated errors of omission by examining two levels of integrity during alternative reinforcement (20 and 60 %) for child compliance following no treatment (baseline) versus treatment at full (i.e., 100 %) integrity. Results indicated that compliance varied according to the level of integrity in place. In addition, compliance in the 60 % integrity condition was high and stable when it followed baseline, but was substantially lower for one participant and slightly lower for a second participant when it followed the full integrity condition. In Experiment 2, we evaluated errors of commission. For three participants, we compared treatment at full integrity to a condition in which errors of commission were made on every trial (i.e., 0 % integrity). For one of these three participants, we also compared treatment at full integrity to baseline and to a condition in which errors of commission were made on 50 % of trials. Results of all four evaluations again indicate that compliance varied according to the level of integrity in place: compliance was low in both the 0 and 50 % integrity conditions, regardless of the preceding condition. These results suggest that during alternative reinforcement of compliance, the effect of occasional errors of omission may depend on the immediately preceding context but that errors of commission are more detrimental.  相似文献   
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