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101.
Distributed Virtual Reality environments based on rewriting systems   总被引:1,自引:0,他引:1  
Ideally, virtual worlds should be dynamic, mutable, and complex in order to be attractive for immersed users. As such worlds can be designed easily by rewriting techniques, we propose a distributed Virtual Reality (VR) system that is based on an interactive animation system using a rewriting technique for geometric and behavioral modeling. The emphasis is on concepts and extensions for the integration of user immersion, user interaction, and networking into a rewriting-based animation system, Finally, the modeling of a ball game with two immersed users, as well as a virtual park, serve as case studies to illustrate the proposed concepts and extensions.  相似文献   
102.
This article describes a second treatment-outcome study of cognitive trauma therapy for battered women with posttraumatic stress disorder (PTSD; CTT-BW). CTT-BW includes trauma history exploration: PTSD education; stress management; exposure to abuse and abuser reminders; self-monitoring of negative self-talk; cognitive therapy for guilt; and modules on self-advocacy, assertiveness, and how to identify perpetrators. One hundred twenty-five ethnically diverse women were randomly assigned to immediate or delayed CTT-BW. PTSD remitted in 87% of women who completed CTT-BW, with large reductions in depression and guilt and substantial increases in self-esteem. White and ethnic minority women benefited equally from CTT-BW. Similar treatment outcomes were obtained by male and female therapists and by therapists with different levels of education and training. Gains were maintained at 3- and 6-month follow-ups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
This study investigated the maternal concerns and emotions that may regulate one form of sensitive parenting, support for children's immediate desires or intentions. While reviewing a videotape of interactions with their 1-year-olds, mothers who varied on depressive symptoms reported concerns and emotions they had during the interaction. Emotions reflected outcomes either to children (child-oriented concerns) or to mothers themselves (parent-oriented concerns). Child-oriented concerns were associated with fewer negative emotions and more supportive behavior. Supportive parenting was high among mothers who experienced high joy and worry and low anger, sadness, and guilt. However, relations depended on whether emotions were child or parent oriented: Supportive behavior occurred more when emotions were child oriented. In addition, as depressive symptoms increased, mothers reported fewer child-oriented concerns, fewer child-oriented positive emotions, and more parent-oriented negative emotions. They also displayed less supportive behavior. Findings suggest that support for children's immediate intentions may be regulated by parents' concerns, immediate emotions, and depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
In 3 experiments, the authors examined part-set cuing effects in younger and older adults. Participants heard lists of category exemplars and later recalled them. Recall was uncued or cued with a subset of studied items. In Experiment 1, participants were cued with some of the category names, and they remembered fewer never-cued categories than a free-recall condition. In Experiment 2, a similar effect was observed for category exemplar cues. There was also an age difference: By some measures, a small number of cues impaired older adults more than younger. Experiment 3 replicated this result and found that older adults were disproportionately slow in the presence of cues. Across experiments, older adults showed robust part-set cuing effects, and sometimes, they were disproportionately impaired by cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Ninety men with alcohol problems and their female partners were randomly assigned to 1 of 3 outpatient conjoint treatments: alcohol behavioral couples therapy (ABCT), ABCT with relapse prevention techniques (RP/ABCT), or ABCT with interventions encouraging Alcoholics Anonymous (AA) involvement (AA/ABCT). Couples were followed for 18 months after treatment. Across the 3 treatments, drinkers who provided follow-up data maintained abstinence on almost 80% of days during follow-up, with no differences in drinking or marital happiness outcomes between groups. AA/ABCT participants attended AA meetings more often than ABCT or RP/ABCT participants, and their drinking outcomes were more strongly related to concurrent AA attendance. For the entire sample, AA attendance was positively related to abstinence during follow-up in both concurrent and time-lagged analyses. In the RP/ABCT treatment, attendance at posttreatment booster sessions was related to posttreatment abstinence. Across treatment conditions, marital happiness was related positively to abstinence in concurrent but not time-lagged analyses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
106.
This article reports on the generalizability, reliability, and construct validity of the Parent Situation Inventory (PSI), a role-play measure of coping skills in parents experiencing problems from an adolescent's drug and alcohol use. Generalizability was robust (.80) and alternate form and test-retest reliability were satisfactory. PSI skillfulness was negatively related to the parent's own substance use and to the adolescent's alcohol use. The PSI shows promise as a reliable and potentially valid measure of coping in this population and has direct implications for developing and evaluating skill-based parent training programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
The article addresses the issue of learning to elearn in borderless programs in a globalised learning landscape and the associated problems of scaffolding the journey across the digital divide. The authors argue that the assumption underlying such courses is that cross-cultural programs are viable because they are conceived and designed to be ‘global’, and that they assume this design to be inclusive. Henning and Van der Westhuizen claim that the global discourse in most domains can take only marginal note of the need to infuse such programs with a local semiotic—a course design criterion for which they argue. They furthermore forward the notion that the majority of the world's prospective elearners need various bridging mechanisms in order to be able to access the broader discourse and that one of these mechanisms can be explored through the metaphor of “information ecologies” as proposed by Nardi and O'Day [Nardi, B.A., & O'Day, V.L. (1999). Information ecologies. Using technology with heart. Cambridge, MA: The MIT Press]. They also conclude that issues of the learners’ trust in the course and its system need to be considered when contemplating programs for diverse target groups. By way of a case study, consisting of three portraitures of adult learners, they explore the limitations of assumed distributed cognition and claim that learning is, in reality, contained/constrained in the familiar local narrative of the novice adult elearners in a rural South African context. The case study illustrates how the resistance to technology and its power base becomes an obstacle for the students and how the support of peers becomes the main scaffolding mechanism for their entry into electronic learning environments. The findings thus show how the social context becomes the facilitator and the scaffold for elearning, more than technology and the curriculum itself.  相似文献   
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In this account, we review the synthesis of [2.2]paracyclophanes in the organic solid state. Reactions in crystalline solids provide a means to obtain molecules with high degrees of stereocontrol that can also be unattainable in solution. We show that [2.2]paracyclophanes form in the solid state stereospecifically and in quantitative yield via intermolecular [2+2] double photodimerization reactions. The double cycloaddition that affords a paracyclophane in the solid state does not readily occur in solution. Small molecules in the form of hydrogen-bond-donor templates can provide access to [2.2]paracyclophanes in a solid by design. A [2.2]paracyclophane obtained using a hydrogen-bond template is shown to exhibit attractive optical properties and has been employed as a building block of a metal-organic framework (MOF).  相似文献   
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