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111.
Personality and social relationships were assessed twice across a 4-year period in a general population sample of 489 German young adults. Two kinds of personality–relationship transaction were observed. First, mean-level change in personality toward maturity (e.g., increase in Conscientiousness and decrease in Neuroticism) was moderated by the transition to partnership but was independent of other developmental transitions. Second, individual differences in personality traits predicted social relationships much better than vice versa. Specifically, once initial correlations were controlled for, Extraversion, Shyness, Neuroticism, self-esteem, and Agreeableness predicted change in various qualities of relationships (especially with friends and colleagues), whereas only quality of relationships with preschool children predicted later Extraversion and Neuroticism. Consequences for the transactional view of personality in young adulthood are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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PURPOSE: Demonstration of a technique for three-dimensional (3-D) assessment of tracheal-stenoses, regarding site, length and degree, based on spiral computed tomography (S-CT). PATIENTS AND METHODS: S-CT scanning and automated segmentation of the laryngo-tracheal tract (LTT) was followed by the extraction of the LTT medial axis using a skeletonization algorithm. Orthogonal to the medial axis the LTT 3-D cross-sectional profile was computed and presented as line charts, where degree and length was obtained. Values for both parameters were compared between 36 patients and 18 normal controls separately. Accuracy and precision was derived from 17 phantom studies. RESULTS: Average degree and length of tracheal stenoses was found to be 60.5% and 4.32 cm in patients compared with minor caliber changes of 8.8% and 2.31 cm in normal controls (p < 0.0001). For the phantoms an excellent correlation between the true and computed 3-D cross-sectional profile was found (p < 0.005) and an accuracy for length and degree measurements of 2.14 mm and 2.53% respectively could be determined. The corresponding figures for the precision were found to be 0.92 mm and 2.56%. CONCLUSION: LTT 3-D cross-sectional profiles permit objective, accurate and precise assessment of LTT caliber changes. Minor LTT caliber changes can be observed even in normals and, in case of an otherwise normal S-CT study, can be regarded as artifacts.  相似文献   
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In this Account, we describe the development of stereospecific, stereoselective, regioselective, and chemoselective carbon-carbon bond-forming reactions of silacyclopropanes that occur under mild conditions. By appropriate choice of metal salt catalyst, the regiochemistry of these reactions may be tuned to give the desired product. Stereoselective nucleophilic substitution reactions and stereospecific oxidation of the C-Si bond to a carbon-oxygen bond demonstrate that the products of these reactions serve as useful intermediates for the synthesis of polyoxygenated organic molecules.  相似文献   
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As the second part of a special issue on Neural Networks and Structured Knowledge, the contributions collected here concentrate on the extraction of knowledge, particularly in the form of rules, from neural networks, and on applications relying on the representation and processing of structured knowledge by neural networks. The transformation of the low-level internal representation in a neural network into higher-level knowledge or information that can be interpreted more easily by humans and integrated with symbol-oriented mechanisms is the subject of the first group of papers. The second group of papers uses specific applications as starting point, and describes approaches based on neural networks for the knowledge representation required to solve crucial tasks in the respective application.The companion first part of the special issue [1] contains papers dealing with representation and reasoning issues on the basis of neural networks.  相似文献   
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Summary The present study investigated the relationship between the use of different internet applications and research productivity, controlling for other influences on the latter. The control variables included dummies for country, discipline, gender and type of organization of the respondent; as well as variables for age, recognition, the degree of society-related and career-related motivation for research, and the size of the collaboration network. Simple variance analyses and more complex negative binomial hurdle models point to a positive relationship between internet use (for personal communication, information retrieval and information dissemination) and research productivity. However, the results should be interpreted with caution as it was not possible to test the role of the internet against other pre-internet tools which fulfil the same functions. Thus instance it may not be the use of e-mail per se, but the degree of communicating with colleagues that makes a productive scientist.  相似文献   
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A number of significant developments augur well for the future of psychoanalysis, both as a method of therapy and as a branch of psychological science. The contributions of Heinz Kohut, together with the explanations for his clinical findings as made possible by developmental psychology, cybernetics, communication science, and neurophysiology are reviewed in the context of their significance for Freud's pioneering discoveries. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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