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We tested the efficacy of two types of educational materials for genetic counseling: a traditional information brochure and one adding a role model story. Brochures were alternated weekly at a prenatal genetics center. Subjects were asked to read the brochure and fill out a questionnaire covering demographics and variables from the health belief model (impact, barriers, motivation, susceptibility, knowledge, severity). A group of 409 pregnant women and 251 male partners participated. Study design was quasiexperimental, using a post-test only comparison group. The brochure with modeling enhanced the perception of both risk and the severity of the disease and was inversely associated with the assessment of barriers, but did not directly impact on the decision to pursue testing; only 12% chose to be tested, with no significant differences between groups. While suggestive, the study is not confirmatory and should be repeated with a more heterogenous group of women.  相似文献   
895.
We investigated the effects of exposure to microgravity on the baseline autonomic balance in cardiovascular regulation using spectral analysis of cardiovascular variables measured during supine rest. Heart rate, arterial pressure, radial flow, thoracic fluid impedance and central venous pressure were recorded from nine volunteers before and after simulated microgravity, produced by 20 hours of 6° head down bedrest plus furosemide. Spectral powers increased after simulated microgravity in the low frequency region (centered at about 0.03 Hz) in arterial pressure, heart rate and radial flow, and decreased in the respiratory frequency region (centered at about 0.25 Hz) in heart rate. Reduced heart rate power in the respiratory frequency region indicates reduced parasympathetic influence on the heart. A concurrent increase in the low frequency power in arterial pressure, heart rate, and radial flow indicates increased sympathetic influence. These results suggest that the baseline autonomic balance in cardiovascular regulation is shifted towards increased sympathetic and decreased parasympathetic influence after exposure to short-term simulated microgravity.  相似文献   
896.
International Journal for Philosophy of Religion -  相似文献   
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Human children, in contrast to other species, are frequently cast as prolific “over‐imitators”. However, previous studies of “over‐imitation” have overlooked many important real‐world social dynamics, and may thus provide an inaccurate account of this seemingly puzzling and potentially maladaptive phenomenon. Here we investigate this topic using a cultural evolutionary approach, focusing particularly on the key adaptive learning strategy of majority‐biased copying. Most “over‐imitation” research has been conducted using consistent demonstrations to the observer, but we systematically varied the frequency of demonstrators that 4‐ to 6‐year‐old children observed performing a causally irrelevant action. Children who “over‐imitate” inflexibly should copy the majority regardless of whether the majority solution omits or includes a causally irrelevant action. However, we found that children calibrated their tendency to acquire the majority behavior, such that copying did not extend to majorities that performed irrelevant actions. These results are consistent with a highly functional, adaptive integration of social and causal information, rather than explanations implying unselective copying or causal misunderstanding. This suggests that our species might be better characterized as broadly “optimal‐” rather than “over‐” imitators.  相似文献   
899.
Evidence accumulation models of decision-making have led to advances in several different areas of psychology. These models provide a way to integrate response time and accuracy data, and to describe performance in terms of latent cognitive processes. Testing important psychological hypotheses using cognitive models requires a method to make inferences about different versions of the models which assume different parameters to cause observed effects. The task of model-based inference using noisy data is difficult, and has proven especially problematic with current model selection methods based on parameter estimation. We provide a method for computing Bayes factors through Monte-Carlo integration for the linear ballistic accumulator (LBA; Brown and Heathcote, 2008), a widely used evidence accumulation model. Bayes factors are used frequently for inference with simpler statistical models, and they do not require parameter estimation. In order to overcome the computational burden of estimating Bayes factors via brute force integration, we exploit general purpose graphical processing units; we provide free code for this. This approach allows estimation of Bayes factors via Monte-Carlo integration within a practical time frame. We demonstrate the method using both simulated and real data. We investigate the stability of the Monte-Carlo approximation, and the LBA’s inferential properties, in simulation studies.  相似文献   
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Research on Child and Adolescent Psychopathology - This paper examines the reliability and validity of parent target problems (PTPs) in a multi-site randomized controlled trial of parent training...  相似文献   
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