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991.
Alan E. Johnson WŁOdztmierz Jarzęba Gilbert C. Walker Paul F. Barbara 《Israel journal of chemistry》1993,33(2):199-206
The class of compounds containing a carbonyl group substituted at the 9 position of anthracene have been studied as new model systems for torsional isomerization in solution. Franck-Condon excitation yields an excited-state distribution near the barrier for isomerization in S1. Using time-resolved fluorescence spectroscopy, we have determined that the relaxation from the barrier region is subpicosecond for three different compounds in all solvents studied. In fact, the relaxation seems to be almost independent of solvent at room temperature, indicating that most of the local friction felt by the twisting carbonyl is internal friction rather than solvent friction. Apparently the small carbonyl is effectively shielded from the solvent by the anthracene ring so the solvent friction is not strong. In contrast to the weak solvent coupling, previously reported gas-phase spectra indicate that the torsion may be strongly coupled to the other vibrational modes of the molecule. Energy flow out of the torsion into these other vibrational modes appears to occur on the subpicosecond time scale. 相似文献
992.
We examined the existence of temporal dimensions of organization culture (e.g., norms of time in organizations) and developed an instrument to measure those dimensions to facilitate cross-organizational and intraorganizational comparisons. A questionnaire designed to measure 15 hypothesized temporal dimensions was completed by 529 respondents from 51 work groups in 23 organizations. The sample was selected to meet certain criteria concerning organization type, organization size, and work group type. A principal components analysis extracted 13 usable scales: Time Boundaries Between Work and Nonwork, Sequencing of Tasks, Punctuality, Allocation, Awareness, Synchronization and Coordination, Variety Versus Routine, Intraorganizational Time Boundaries, Future Orientation, Schedules and Deadlines, Work Pace, Autonomy of Time Use, and Quality Versus Speed. Two hypothesized scales (Buffer in Planning and Buffer in Workday) did not emerge. Applications of the Time Dimensions Scales are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Abrams Dominic; Viki G. Tendayi; Masser Barbara; Bohner Gerd 《Canadian Metallurgical Quarterly》2003,84(1):111
In Studies 1 and 2, after reading an acquaintance-rape but not a stranger-rape scenario, higher benevolent sexist but not hostile sexist participants blamed the victim significantly more. In Study 2, higher hostile sexist but not benevolent sexist male participants showed significantly greater proclivity to commit acquaintance (but not stranger) rape. Studies 3 and 4 supported the hypothesis that the effects of benevolent sexism and hostile sexism are mediated by different perceptions of the victim, as behaving inappropriately and as really wanting sex with the rapist. These findings show that benevolent sexism and hostile sexism underpin different assumptions about women that generate sexist reactions toward rape victims. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
The influence of testosterone and estrogen on memory was investigated in 33 healthy young men. Tests of visual memory, visuospatial ability, verbal memory, and attention were administered, and circulating levels of estradiol and free testosterone were measured. Participants with high levels of estradiol performed better on 2 measures of visual memory than did those with normal but lower levels. There were no differences between individuals with high and low levels of testosterone on any cognitive measure. These results support the contention that estradiol influences memory in young men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Holloway Elizabeth L.; Freund Richard D.; Gardner Sharon L.; Nelson Mary Lee; Walker Barbara R. 《Canadian Metallurgical Quarterly》1989,36(1):88
Power and involvement are two fundamental dimensions of primary relationships. We studied the relevance of these two dimensions in the supervisory relationship. A multiple-case-study approach was used to describe systematically the discourse of the five supervision interviews of the Goodyear (1982) series, Psychotherapy Supervision by Major Theorists; we compared these results with previous findings that have reported impressional characteristics of the interviews. The content-analysis scheme used to describe the discourse was developed by Penman (1980) and includes both manifest and latent levels of communication organized on the two dimensions of power and involvement. The sequences of verbal messages in each of the interviews were analyzed by using unidirectional and dominance sequential tests. The results indicate that although there was a primary pattern of teacher–learner interaction in all interviews, each interview exhibited a unique style with regard to the sequences of messages between supervisor and supervisee and the characteristics of power and involvement as defined by the Penman scheme. We discuss the characteristics of the interviews, as described by the results of the content and sequential analyses, in relation to the theoretical orientation of each supervisor. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Judges were asked to fairly assign priority ratings to hypothetical candidates applying to medical school, given information about their Medical College Aptitude Test scores, grade-point averages, and group memberships (majority or minority). The affirmative action goal and the qualifications of minorities relative to majorities in the applicant pool were also manipulated. When there is no specified affirmative action goal nor differences between groups in the applicant pool, minorities and majorities are treated similarly. When either group differences in the applicant pool occur or affirmative action goals are introduced, decision makers assign higher priority ratings to minorities than to equally qualified majority applicants. When both factors are operating, minorities receive an even bigger boost. Results are consistent with the hypothesis that decision makers evaluate minority and majority candidates in the same way; differences between groups occur in the response function. Equally qualified majority and minority candidates are assigned to different categories, depending on the size of the affirmative action goal and the extent to which the two groups differ in the applicant pool. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
A software environment for the specification and analysis ofproblems of coordination and concurrency
Aggarwal S. Barbara D. Meth K.Z. 《IEEE transactions on pattern analysis and machine intelligence》1988,14(3):280-290
The SPANNER software environment for the specification and analysis of concurrent process coordination and resource sharing coordination is described. In the SPANNER environment, one can formally produce a specification of a distributed computing problem, and then verify its validity through reachability analysis and simulation. SPANNER is based on a finite-state machine model called the selection/resolution model. The capabilities of SPANNER are illustrated by the analysis of two classical coordination problems: (1) the dining philosophers; and (2) Dijkstra's concurrent programming problem. In addition, some of the more recently implemented capabilities of the SPANNER system are discussed, such as process types and cluster variables 相似文献
998.
Fisher William A.; Fisher Jeffrey D.; Rye Barbara J. 《Canadian Metallurgical Quarterly》1995,14(3):255
Psychological determinants of AIDS-preventive behaviors were examined from the perspective of the theory of reasoned action in prospective studies of gay men, heterosexual university students, and heterosexual high school students. Across samples, preventive behaviors, and prospective intervals of 1 and 2 months' duration, AIDS-preventive behaviors were predicted by behavioral intentions; behavioral intentions were a function of attitudes and norms; and attitudes and norms were a function of their theorized basic underpinnings. Discussion focuses on the development of AIDS-prevention interventions that modify intentions, attitudes, and norms concerning performance of AIDS-preventive behaviors by targeting the empirically identified underpinnings of attitudes and norms related to specific preventive behaviors in specific populations of interest. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Examined the relationship between attachment theory and relationship problems in children. Research and theory that can assist counselors and teachers to better understand the etiology and management of aggressive and avoidant children during early childhood are discussed. Aggressive and withdrawn behaviors are seen as the predictable results of unsupportive and/or destructive early environments. Early parenting, the quality of ongoing parenting relationships, levels of stress, quality of limit setting, and support all contribute to the behavior of the child with relationship problems. A model of change in the process of attachment sensitive play therapy is described in 4 stages with illustrative case material. The roles of the teacher and school in working with the play therapist are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Mobile Networks and Applications - 相似文献