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991.
992.
This study assessed the impact of a school-based program aimed at preventing disordered eating. The program was based on the media-literacy approach and has interactive format. The program was assessed under strong methodological conditions. Seven schools with 263 Spanish adolescent girls in the area of Barcelona, were randomly assigned to either the complete prevention program condition, the partial program condition or the non-treatment control condition, and assessed at pre, post and 6-month follow-up. The program was effective in generating positive changes at follow-up. The effects sizes (ES(d) = 0.29 to ES(d) = 0.38) were greater, on average, than that obtained up to now in selective-universal programs, and similar or greater than that achieved by targeted prevention programs. The results indicate a greater and relevant effect size of the intervention in those participants who completed the inter-session interactive activities (ES(d) = 0.29 to ES(d) = 0.45) although the differences were not significant. These results suggest the importance of monitoring adherence to the activities in all programs defined as "interactive". The implications and limitations of this study are discussed.  相似文献   
993.
The aim of this paper was to develop an instrument to assess levels of stress experienced by Latin-American immigrants in their acculturative process in Spain. A sample of 692 immigrants from Latin America, aged 20 to 63 years, took part on this study (54.9% males and 45.1% females). A 24-item questionnaire with high reliability (.92) was elaborated. Six factors related to acculturative stress were found: 1) discrimination and rejection; 2) differences with the out-group (native Spaniards); 3) citizenship problems and legality; 4) problems concerning social relationships with other immigrants; 5) nostalgia and longing; and 6) family break-up. Our findings show that participants have a high level of stress related to nostalgia and longing, family break-up, and the perception of discrimination and rejection by natives. The usefulness of the instrument and its applications and restrictions are discussed.  相似文献   
994.
995.
A current theory of attention posits that several micro-indices of attentional vigilance are dependent on activation of the locus coeruleus, a brainstem nucleus that regulates cortical norepinephrine activity (Aston-Jones et al., 1999). This theory may account for many findings in the infant literature, while highlighting important new areas for research and theory on infant attention. We examined the visual behaviors of n = 16 infants (6-7 months) while they attended to multiple spatially distributed targets in a naturalistic environment. We coded four measures of attentional vigilance, adapted from studies of norepinergic modulation of animal attention: rate of fixations, duration of fixations, latency to reorientation, and target 'hits'. These measures showed a high degree of coherence in individual infants, in parallel with findings from animal studies. Results also suggest that less vigilant infants showed greater habituation to the trial structure and more attentiveness to less salient stimuli during periods of high attentional competition. This pattern of results is predicted by the Aston-Jones model of attention, but could not be explained by the standard information processing model.  相似文献   
996.
The use of in-vehicle touch screen devices is currently common in both military and civilian vehicles; despite this, the effects of motion on touch screen device operation within vehicles remains largely unexplored. This article describes a study that examined, using driving simulation, the influences of motion on performance, workload and usability when using a touch screen in-vehicle battle management system. Acting in the role of battle management system operator, 20 participants undertook four simulated drives, two under high motion (representative of an unsealed road) and two under normal motion (representative of a sealed road), whilst performing various battle management tasks. In the high motion condition, lower accuracy and longer task completion times were found, along with greater levels of subjective and physiological workload and lower levels of perceived device usability, when compared to the normal motion condition. The findings indicate that, compared to normal motion, the high motion condition impaired key aspects of battle management system operation. In closing, the importance of considering motion and its effects during touch screen system design is discussed.  相似文献   
997.
Although the majority of research focuses on the risks and disadvantages of online gaming, the present authors suggest that online games also represent new ways of satisfying basic human needs within the conditions of modern society. The aim of our present study was to reveal and operationalize the components of the motivational basis of online gaming. A total 3,818 persons (90.6% males; mean age 20.9 years, SD = 5.81) were recruited through websites providing online games. A combined method of exploratory and confirmatory factor analysis was applied. The results confirmed our preliminary model as we identified seven motivational factors (social, escape, competition, coping, skill development, fantasy, and recreation), which were used to develop the 27-item Motives for Online Gaming Questionnaire (MOGQ). The seven dimensions identified seem to cover the full range of possible motives for gaming, and the MOGQ proved to be an adequate measurement tool to assess these motives.  相似文献   
998.
999.
Our primary focus is on analysis of the concept of voluntariness, with a secondary focus on the implications of our analysis for the concept and the requirements of voluntary informed consent. We propose that two necessary and jointly sufficient conditions must be satisfied for an action to be voluntary: intentionality, and substantial freedom from controlling influences. We reject authenticity as a necessary condition of voluntary action, and we note that constraining situations may or may not undermine voluntariness, depending on the circumstances and the psychological capacities of agents. We compare and evaluate several accounts of voluntariness and argue that our view, unlike other treatments in bioethics, is not a value-laden theory. We also discuss the empirical assessment of individuals' perceptions of the degrees of noncontrol and self-control. We propose use of a particular Decision Making Control Instrument. Empirical research using this instrument can provide data that will help establish appropriate policies and procedures for obtaining voluntary consent to research.  相似文献   
1000.
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