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941.
Abstract

The dismantling of apartheid and the postapartheid dispensation had far-reaching implications for all the citizens of South Africa. In an urban sample of White Afrikaans-speaking South Africans (Afrikaners) in postapartheid South Africa, the authors investigated perceptions of threat to ethnic identity, as well as correlates of those perceptions. The respondents experienced threat on 2 levels: The 1st was distinctive continuity, the concern that their ethnic group would not continue as a distinctive group in society. The 2nd was the evaluative dimension of ethnic identity (i.e., well-being), the concern that group membership would no longer contribute to positive self-esteem. The respondents experienced greater threat on the 2nd level, reflecting predominantly negative experiences as White Afrikaans-speaking persons in postapartheid South Africa. A high threat perception on the 2nd level was associated with (a) a perception of other groups' negative evaluations of their ethnic group, (b) negative attitudes toward political changes, and (c) perceptions of illegitimacy and instability of the postapartheid political system. The respondents who felt that Afrikaners would not continue as a distinctive group in society had a more positive attitude toward the sociopolitical changes, did not show strong ethnic identification, and had a negative collective self-esteem. They were also politically more liberal. Those findings are discussed in relation to theoretical expectations.  相似文献   
942.
Abstract

In a sample of 1,166 Catholic high school students (age = 13–18 years), the author used confirmatory factor analysis to validate a 30-item instrument that assesses 6 dimensions of attitude to Christianity (viz., attitude to prayer, attitude to God, attitude to Jesus, attitude to the Bible, attitude to Christian practice, attitude to social justice). Goodness-of-fit indices for the proposed measurement model revealed that the model fitted the data very well, thus confirming the instrument's structure. A correlation analysis revealed associations between religious behavior and attitude to Christianity.  相似文献   
943.
Emerging evidence suggests that nicotine may enhance short‐term memory. Some of this evidence comes from nonhuman primate research using a procedure called delayed matching‐to‐sample, wherein the monkey is trained to select a comparison stimulus that matches some physical property of a previously presented sample stimulus. Delays between sample stimulus offset and comparison stimuli onset are manipulated and accuracy is measured. The present research attempted to systematically replicate these enhancement effects with pigeons. In addition, the effects of nicotine were assessed under another, more dynamic, memory task called titrating‐delay matching‐to‐sample. In this procedure, the delay between sample offset and comparison onset adjusts as a function of the subject's performance. Correct matches increase the delay, mismatches decrease the delay, and titrated delay values serve as the primary dependent measure. Both studies examined nicotine's effects under acute and chronic administration. Neither provided clear or compelling evidence of memory enhancement following nicotine administration despite reliable and systematic dose‐related changes in response latency measures. A modest dose‐related effect on accuracy was found, but the magnitude of the effect appears to be directly related to tactics of data analysis involving best‐dose analyses of a very circumscribed subset of trial types.  相似文献   
944.
Thirty college students attempted to form three 3-node 5-member equivalence classes under the simultaneous protocol. After concurrent training of AB, BC, CD, and DE relations, all probes used to assess the emergence of symmetrical, transitive, and equivalence relations were presented for two test blocks. When the A-E stimuli were all abstract shapes, none of 10 participants formed classes. When the A, B, D, and E stimuli were abstract shapes and the C stimuli were meaningful pictures, 8 of 10 participants formed classes. This high yield may reflect the expansion of existing classes that consist of the associates of the meaningful stimuli, rather than the formation of the ABCDE classes, per se. When the A-E stimuli were abstract shapes and the C stimuli became S(D)s prior to class formation, 5 out of 10 participants formed classes. Thus, the discriminative functions served by the meaningful stimuli can account for some of the enhancement of class formation produced by the inclusion of a meaningful stimulus as a class member. A sorting task, which provided a secondary measure of class formation, indicated the formation of all three classes when the emergent relations probes indicated the same outcome. In contrast, the sorting test indicated "partial" class formation when the emergent relations test indicated no class formation. Finally, the effects of nodal distance on the relatedness of stimuli in the equivalence classes were not influenced by the functions served by the C stimuli in the equivalence classes.  相似文献   
945.
Domestic hens responded under multiple fixed‐ratio fixed‐ratio schedules with equal fixed ratios. One component provided immediate reinforcement and the other provided reinforcement after a delay, signaled by the offset of the key light. The components were presented quasirandomly so that all four possible transitions occurred in each session. The delay was varied over 0, 4, 8, 16, and 32 s with fixed‐ratio 5 schedules, and over 0, 8 and 32 s with fixed‐ratio 1, 15 and 40 schedules. Main effects of fixed‐ratio value and delay duration were detected on between‐ratio pauses. Pauses were longer when the multiple‐schedule stimulus correlated with a delayed‐reinforcer component was presented, with the longest pauses occurring at the transition from a component with an immediate reinforcer to one with a delayed reinforcer. Pause durations were shortest during immediate components. Overall, both the presence or absence of a delay in the upcoming component, and the presence or absence of a delay in the preceding component affected pause length, but the upcoming delay had the larger effect. Thus changes in delay had similar effects to past reports of the effects of changes in response force, response requirement, and reinforcer magnitude in multiple fixed‐ratio fixed‐ratio schedules.  相似文献   
946.
Bringing evidence based programs to scale was a major initial impetus for the development of the Interactive Systems Framework for Dissemination and Implementation (ISF). The ISF demonstrates the importance of the Support System in facilitating the uptake of innovations in the community (the Delivery System). Two strategies that members of the Support System commonly use are training‐of‐trainers (TOT) models and technical assistance (TA). In this article, we focus on the role of the Support System in bringing evidence‐based programs (EBPs) to scale in the Delivery System using a case example, with special attention on two strategies employed by Support Systems—trainingoftrainers (TOT) and proactive technical assistance. We then report on findings from a case example from the Promoting Science Based Approaches to Teen Pregnancy Prevention project that furthers our conceptualization of these strategies and the evidence base for them. We also report on the limitations in the literature regarding research on TOTs and proactive TA and provide suggestions for future research on TOTs and proactive TA that will enhance the science and practice of support in the ISF. Special Issue: Advances in Bridging Research and Practice Using the Interactive System Framework for Dissemination and Implementation; Guest Editors: Abraham Wandersman, Paul Flaspohler, Catherine A. Lesesne, Richard Puddy; Action Editor: Emilie Phillips Smith  相似文献   
947.
The aim of this research was to investigate the feasibility of achieving Improving Access to Psychological Therapies (IAPT) for people from Black, Asian and Minority Ethnic (BAME) communities living in the UK, with specific reference to Bengali, Urdu, Tamil and Somali speaking communities. Focus groups were carried out with each of the communities to investigate how they conceptualise and experience ‘mental health issues’ and what they do when faced with what they regard as these issues. A thematic analysis of the data suggested that participants did not fully understand common conceptualisations about mental health issues, nor did they know how to seek mental health support. Implications of cultural barriers and recommendations for IAPT outcomes for the four communities are discussed.  相似文献   
948.
Previous research has shown that rats can learn matching-to-sample relations with olfactory stimuli; however, the specific characteristics of this relational control are unclear. In Experiment 1, 6 rats were trained to either match or nonmatch to sample in a modified operant chamber using common household spices as olfactory stimuli. After matching or nonmatching training with 10 exemplars, the contingencies were reversed with five new stimuli such that subjects trained on matching were shifted to nonmatching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new exemplars. In Experiment 2, 9 rats were trained with matching procedures in an arena that provided for 18 different spatial locations for comparison stimuli. Five subjects were trained with differential reinforcement outcomes and 4 with only one type of reinforcer. Differential outcomes and multiple exemplars facilitated learning, and there was strong evidence for generalization to new stimuli for most rats that acquired several conditional discriminations. Performances with novel samples were generally above chance, but rarely reached the high levels obtained during baseline with well-trained stimulus relations. However, taken together, the data from the two experiments extend previous work, show that rats can learn both match and nonmatch relations with different experimental protocols, and demonstrate generalization to novel sample stimuli.  相似文献   
949.
Training context can influence resistance to disruption under differing reinforcement schedules. With nonhumans, when relatively lean and rich reinforcement schedules are experienced in the context of a multiple schedule, greater resistance is found in the rich than the lean component, as described by behavioral momentum theory. By contrast, when the schedules are experienced in separated blocks of sessions (i.e., as single schedules), resistance is not consistently greater in either component. In the current study, two groups of 6 children with intellectual disabilities responded to stimuli presented in relatively lean or rich components. For both, reinforcers were delivered according to the same variable-interval reinforcement schedule; additionally, the rich component included the delivery of response-independent reinforcers. The Within group was trained on a multiple schedule in which lean and rich components alternated regularly within sessions; the Blocked group was trained on two single schedules in which sessions with either the lean or rich schedule were conducted in successive blocks. Disruption tests presented a concurrently available alternative stimulus disrupter signaling the availability of tangible reinforcers. All 6 Within participants showed greater resistance to disruption in the rich component, consistent with behavioral momentum theory. By contrast, there was no consistent or significant difference in resistance for Blocked participants. This finding is potentially relevant to the development of interventions in applied settings, where such interventions often approximate single schedules and include response-independent reinforcers.  相似文献   
950.
The personality trait Openness/Intellect reflects the tendency to be imaginative, curious, perceptive, artistic, and intellectual - all characteristics that involve cognitive exploration. Little is known about the biological basis of Openness/Intellect, but the trait has been linked to cognitive functions of prefrontal cortex, and the neurotransmitter dopamine plays a key role in motivation to explore. The hypothesis that dopamine is involved in Openness/Intellect was supported by examining its association with two genes that are central components of the prefrontal dopaminergic system. In two demographically different samples (children: N = 608; adults: N = 214), variation in the dopamine D4 receptor gene (DRD4) and the catechol-O-methyltransferase gene (COMT) predicted Openness/Intellect, as main effects in the child sample and as a gene-gene interaction in adults.  相似文献   
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