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11.
The cognitive-environmental model (CEM; M. Fishbein et al., 1991) was used to understand the unprotected sexual behaviors of 156 gay, lesbian, and bisexual youths. Unprotected anal sex among the males was associated directly with poor protection skills (e.g., incorrect use of barrier methods, such as condoms), poor intentions to use barrier methods, and poor norms by sexual partners concerning barrier methods. Furthermore, the association between low self-efficacy and increasing unprotected anal sex was attributed to poor intentions. Direct associations of unprotected oral sex with poor intentions and poor partner norms also emerged, as did an indirect relation between unprotected oral sex and low self-efficacy via poor intentions. These last 3 findings were replicated when examining unprotected oral or vaginal-digital sex among the females. Relations among the CEM factors supported some CEM-theoretical propositions.  相似文献   
12.
Pigeons' responses were reinforced on a variant of a mixed variable-interval extinction schedule of reinforcement in which the transition to the higher reinforcement rate was signaled by a trace stimulus projected on the response key prior to the onset of the component correlated with food delivery. In the first of two experiments, the duration of the trace stimulus preceding the component correlated with food delivery was varied from 1.5 to 50.0 s and in the second experiment, the reinforcement frequency in the same component was varied from 10 to 60 reinforcers per hour. Pigeons pecked at the trace stimulus preceding the onset of the component correlated with food delivery even though responding was not reinforced in its presence and only one of the changes in reinforcement rate (i.e., from extinction to reinforcement) was signaled. The rate of pecking during the trace stimulus was a function of its duration but not of the reinforcement frequency in the following component. Higher rates generally occurred at the shorter trace-stimulus durations. Component responding following the offset of the trace stimulus was under discriminative control of the trace stimulus whether or not responding occurred in the presence of the trace stimulus.  相似文献   
13.
Disruption of the dorsal frontostriatal pathways in Parkinson’s disease (PD) is associated with impairments in motivation, as well as in executive function. The goal of this study was to investigate whether these impairments are related and, if so, whether the disruption of frontostriatal pathways compromises the ability to process the motivational aspects of feedback in such tasks. In Experiment 1, informative feedback improved the performance of young, healthy participants in a task-switching paradigm. This task-switching paradigm was then used in Experiment 2 to test whether feedback would improve the performance of 17 PD patients and age-matched controls. The PD group benefitted from feedback to the same degree as control participants; however, depression scores on the Beck Depression Inventory were significantly related to feedback usage, especially when response selection demands were high. Regardless of feedback, PD patients were more impaired when response demands were high than in an equally difficult condition with low action demands. These results suggest that response selection is a core impairment of insufficient dopamine to the dorsal frontal striatal pathways.  相似文献   
14.
Service-oriented computing, an emerging paradigm for distributed computing based on the use of services, is calling for the development of tools and techniques to build safe and trustworthy systems, and to analyse their behaviour. Therefore, many researchers have proposed to use process calculi, a cornerstone of current foundational research on specification and analysis of concurrent, reactive, and distributed systems. In this paper, we follow this approach and introduce C
WS, a process calculus expressly designed for specifying and combining service-oriented applications, while modelling their dynamic behaviour. We show that C
WS can model all the phases of the life cycle of service-oriented applications, such as publication, discovery, negotiation, orchestration, deployment, reconfiguration and execution. We illustrate the specification style that C
WS supports by means of a large case study from the automotive domain and a number of more specific examples drawn from it.  相似文献   
15.
While perceiving speech, people see mouth shapes that are systematically associated with sounds. In particular, a vertically stretched mouth produces a /woo/ sound, whereas a horizontally stretched mouth produces a /wee/ sound. We demonstrate that hearing these speech sounds alters how we see aspect ratio, a basic visual feature that contributes to perception of 3D space, objects and faces. Hearing a /woo/ sound increases the apparent vertical elongation of a shape, whereas hearing a /wee/ sound increases the apparent horizontal elongation. We further demonstrate that these sounds influence aspect ratio coding. Viewing and adapting to a tall (or flat) shape makes a subsequently presented symmetric shape appear flat (or tall). These aspect ratio aftereffects are enhanced when associated speech sounds are presented during the adaptation period, suggesting that the sounds influence visual population coding of aspect ratio. Taken together, these results extend previous demonstrations that visual information constrains auditory perception by showing the converse - speech sounds influence visual perception of a basic geometric feature.  相似文献   
16.
This study involved the translation, cultural adaptation and validation of the Athletic Coping Skills Inventory (ACSI-28) for a Spanish-speaking sport environment. The sample was made up of 1,253 Spanish athletes, 967 males and 286 females. Confirmatory factor analysis (CFA) showed that the 7-factor structure found in the English version was replicated in the Spanish translation in both males and females. Likewise, the reliability coefficients were similar to those of the English version, with values exceeding .80 for the total score. Several of the subscales correlated positively with sports experience and performance level. The Spanish version of the ACSI-28 thus maintains the factor structure of the original and exhibits similar psychometric properties. Consequently, it can reliably be applied to Spanish-speaking athletes for research and evaluation purposes.  相似文献   
17.
We examined the associations between parental educational/occupational levels and cognitive performance in Spanish adolescents. Cognitive performance was measured by a validated Scholar Aptitudes test in 2,162 participants. Parental educational and occupational levels were positively associated with all specific cognitive abilities and the overall score (p<001 to .04). The odds ratios of having a high cognitive performance (top quartile) in adolescents with high parental educational level were 1.6 to 1.7 times higher than for those with a low parental educational level. Similarly, the odds ratios were 1.9 to 2.4 times higher for adolescents with high parental occupational level. These findings suggest an association between parental educational/occupational levels and cognitive performance in Spanish adolescents and support the parents' role in the creation of a stimulating intellectual environment.  相似文献   
18.
Whereas the visual modality tends to dominate over the auditory modality in bimodal spatial perception, the auditory modality tends to dominate over the visual modality in bimodal temporal perception. Recent results suggest that the visual modality dominates bimodal spatial perception because spatial discriminability is typically greater for the visual than for the auditory modality; accordingly, visual dominance is eliminated or reversed when visual-spatial discriminability is reduced by degrading visual stimuli to be equivalent or inferior to auditory spatial discriminability. Thus, for spatial perception, the modality that provides greater discriminability dominates. Here, we ask whether auditory dominance in duration perception is similarly explained by factors that influence the relative quality of auditory and visual signals. In contrast to the spatial results, the auditory modality dominated over the visual modality in bimodal duration perception even when the auditory signal was clearly weaker, when the auditory signal was ignored (i.e., the visual signal was selectively attended), and when the temporal discriminability was equivalent for the auditory and visual signals. Thus, unlike spatial perception, where the modality carrying more discriminable signals dominates, duration perception seems to be mandatorily linked to auditory processing under most circumstances.  相似文献   
19.
The purpose of this study is to evaluate the neuropsychological performance in a ≥90-year-old population with Alzheimer disease (AD) in comparison with younger elderly patients. We retrospectively studied all patients with AD attended in a specialized clinic between 1999 and 2011. Age, sex, educational level, and sensory loss data were collected. Neuropsychological evaluation included Mini-Mental State Examination and Global Deterioration Scale. We used the eight Cambridge Cognitive Assessment (CAMCOG-R) domains to evaluate and compare the neuropsychological performance in the younger than 90 years old (<90) and older than 90 years old (≥90) groups. We selected 2931 patients, 2897 <90 (98.83%) and 34 ≥90 years old (1.17%). The ≥90 group had significant lower punctuations in memory, praxis, and abstract thinking CAMOCG-R domains with 1.49, 0.75, and 0.58 less points, respectively, (p < 0.05). Neuropsychological characteristics of cognitive decline seem to be different in ≥90 compared to <90 years old patients. According to age, the biggest differences in the CAMCOG-R performance are in the memory, praxis, and abstract thinking domains.  相似文献   
20.
The aim of this study was to assess a predictive model of posttraumatic growth and posttraumatic stress symptoms in children and adolescents exposed to the earthquake in Chile in 2010. 325 children (47.4% male), aged between 10 and 15 years, were surveyed 12 months after the earthquake. The following tests were administered: the posttraumatic growth inventory for children in its brief version of Kilmer et al., the child PTSD symptom scale of Foa et al., the rumination scale for children of Crider et al., along with a scale to assess the trauma severity and a socio-demographic questionnaire. The model was assessed through a path analysis, which showed that deliberate rumination mediated the relationship between trauma severity and intrusive rumination with posttraumatic growth, that intrusive rumination mediated the relationship between the severity of the event and posttraumatic stress symptoms and that the latter mediated the relationship between intrusive rumination and posttraumatic growth. The sex was included as control variable in the path model. The final model achieved adequate fit indexes. The relevance of rumination processes for the development of the psychological consequences in children and adolescents following a natural disaster and their implications for clinical is discussed.  相似文献   
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