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Background: In the DSM-5, the diagnosis of hypochondriasis was replaced by two new diagnositic entities: somatic symptom disorder (SSD) and illness anxiety disorder (IAD). Both diagnoses share high health anxiety as a common criterion, but additonal somatic symptoms are only required for SSD but not IAD. Design: Our aim was to provide empirical evidence for the validity of these new diagnoses using data from a case–control study of highly health-anxious (n = 96), depressed (n = 52), and healthy (n = 52) individuals. Results: The individuals originally diagnosed as DSM-IV hypochondriasis predominantly met criteria for SSD (74%) and rarely for IAD (26%). Individuals with SSD were more impaired, had more often comorbid panic and generalized anxiety disorders, and had more medical consultations as those with IAD. Yet, no significant differences were found between SSD and IAD with regard to levels of health anxiety, other hypochondriacial characteristics, illness behavior, somatic symptom attributions, and physical concerns, whereas both groups differed significantly from clinical and healthy controls in all of these variables. Conclusion: These results do not support the proposed splitting of health anxiety/hypochondriasis into two diagnoses. Further validation studies with larger samples and additional control groups are warranted to prove the validity of the new diagnoses.  相似文献   
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This study investigated the effects of environmental enrichment on the cognitive performance of female conventional farm (growing) pigs in a spatial holeboard task. Ten pairs of littermates matched for weight were used. From each litter, one piglet was randomly assigned to a barren environment; the other was assigned to an enriched environment from 4 weeks of age. The enriched environment was double the size of the barren environment, had a floor covered with straw, a rooting area filled with peat, and one of the four different enrichment toys which were exchanged daily. Starting at 11 weeks of age, all pigs were tested in a spatial holeboard discrimination task in which 4 out of 16 holes were baited. Furthermore, basal salivary cortisol levels of all pigs were determined after the end of all testing. All pigs were able to acquire the pattern of baited holes (acquisition phase, 40 trials) and the diagonally mirrored pattern (reversal phase, 20 trials). During the acquisition phase, the reference memory performance of the enriched-housed pigs was better than that of their barren-housed littermates, i.e. they reduced visits to the unbaited set of holes. During the reversal phase, enriched-housed pigs had a better general working memory performance than the barren-housed pigs as indicated by reduced revisits to holes already visited during a trial, irrespective of whether they were of the baited or the unbaited set. The enriched-housed pigs also searched for the hidden bait faster during both phases. The environments did not affect basal salivary cortisol levels. In conclusion, environmental enrichment slightly improved the cognitive performance of pigs in a spatial learning task. We hypothesise that the long period of habituation to and testing in the holeboard acted as enrichment that partially reduced the effects of barren housing.  相似文献   
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Summary  Evolution is a time process. It proceeds in steps of definite length. The probability of each step is relatively high, so self organization of complex systems will be possible in finite time. Prerequisite for such a process is a selection rule, which certainly exists in evolution. Therefore, it would be wrong to calculate the probability of the formation of a complex system solely on the basis of the number of its components and as a momentary event.  相似文献   
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Adaptation to field displacement during head movements in the direction with the head rotation and in the direction against it was produced under otherwise identical conditions and compared; the field displacement rate was also varied. A rapid training procedure was used, and a novel one-trial test was employed that could measure the adaptation well enough to compare the effects of various training conditions. The one-trial test measured the magnitude of one of the manifestations of adaptation, the apparent displacement of a stationary target during head movements. This apparent horizontal target displacement was transformed into an oblique one by having the head movements that brought forth the apparent target displacement simultaneously cause an objective vertical target displacement. The slant of the resultant apparent motion path varied with the magnitude of the apparent horizontal target displacement. It was measured by having S reproduce its slant angle. It was found that adaptation to field displacement in the direction with the head rotation was consistently greater than adaptation to the opposite displacement conditions. An explanation for this result is offered.  相似文献   
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In the research area of multiple criteria decision making, very few publications exist that explicitly design the simulation of a decision maker (DM) in an interactive approach. For this reason, we outline some methods widely used in the literature to identify common assumptions of simulating the DM's responses and the required input preference information. Our paper aims at covering the identified gap by introducing experimental concepts. Such concepts are used for theoretical analyses of a combined search‐and‐decision‐making procedure. Simulating the DM is a fruitful idea because the algorithm can be tested without integrating a human decision maker. Finally, we conduct experiments based on the proposed settings for a multiobjective inventory routing problem, which is a relevant and challenging logistic problem. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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In computer security parlance, a hacker is an individual who actively seeks and takes advantage of flaws and weaknesses of a computer network or system. In recent years, one has seen the rise of hacking, often as a form of protest and retaliation for reasons ranging from political to social, but the question remains as to what really motivates an individual to hack a computer network? Using the Q-method, the study aimed to develop a classification of the motivation of computer hackers. This was done with the use of 43 participants who were subjected to preliminary interviews and the sorting method. The statements from the interviews were categorized that resulted in seven conceptual themes, namely social-positive, social-negative, intellectual gain, self-satisfaction, economic rewards, technological-positive and technological-negative. From these themes, three distinct profiles emerged and were used to describe the motivation of hackers.  相似文献   
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