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91.
Why are European Jews migrating to Israel in significant numbers? Israeli leaders and popular press reports suggest that incidents of antisemitism have reached such high levels across Europe, even in fully democratic countries, that Jews are leaving once again to escape persecution and violence. Others suggest that Jews are migrating for the same reasons other migrants do: for greater economic opportunity. Until now, we have had no way of weighing the relative merit of these claims, hampered by the absence of reliable comparative data on antisemitism in Europe. Leveraging a new dataset compiled by the author, this study tests these competing hypotheses and finds that European Jews migrate because of greater economic opportunity in Israel. While concerns about antisemitism in Europe are at record highs and more Jews are considering moving to Israel than ever before in the post-war era, so far most Jewish migration is to take advantage of better economic opportunities in Israel.  相似文献   
92.
The IIFF model of organ donation holds that the simultaneous presence of four factors directly influence donor registration: (1) immediate and complete registration opportunity (ICRO), (2) information, (3) focused engagement, and (4) favorable activation. Two field experiments examined the impact of an ICRO on organ donation registration. In Study 1, participants were at town halls where they knew organ donation was to be discussed. Registration cards were distributed and then collected at the end of the session in half of the town halls. For the other half, participants were asked to mail in completed cards. In three US cities, participants given an ICRO registered at a significantly greater rate (z?=?4.865, p?相似文献   
93.
Only recently has the mental health community recognized the applicability of diagnostic criteria for posttraumatic stress disorder (PTSD) in children and adolescents, including a consideration of specific age-related features. This paper provides a current review of the literature on PTSD pertaining to children and adolescents. Following a discussion of issues on diagnostic criteria and assessment of this affective disorder in this population, there is an overview of the existing literature on prevalence, comorbidity, risk factors, parental and family factors, and issues of gender and age of onset. The remainder of the paper focuses on the range of traumatic stressors in children and adolescents that can result in PTSD, including natural or human disasters, war and violence, chronic or life-threatening medical conditions, community violence and the witnessing of traumatic events, and physical and/or sexual abuse and other forms of interpersonal violence. Throughout the paper, there is an emphasis on the importance of considering developmental factors. Finally, implications of the existing literature for future areas of research are addressed.  相似文献   
94.
National Guard (NG) soldiers returning from deployments in Iraq and Afghanistan were surveyed at 6 and 12 months following their return (N = 970). The overall prevalence of suicide risk at 6 and 12 months following their return was assessed, as were changes in suicide risk among soldiers initially at high or low risk. Factors associated with changes in risk were assessed. The percentage of NG soldiers with high suicide risk increased from 6.8% at 6 months to 9.2% at 12 months (odds ratio = 1.7, p = .02). In the 882 soldiers initially at low risk, 5.9% (52/882) became high risk at 12 months; in the 64 soldiers initially at high risk, 46.9% (30/64) became low risk at 12 months. Initial levels of depressive symptoms were predictive of changing to high risk; this association appeared to be partially explained by soldier reports of increased search in the meaning in life and higher levels of perceived stress. Because suicide risk increases over the first 12 months, continued risk assessments during this time period should be considered. Supporting soldiers to find meaning in their life after deployment and enhancing their capacity to cope with perceived stress may help prevent increases in suicide risk over time.  相似文献   
95.
Distances tend to be underperceived in virtual environments (VEs) by up to 50%, whereas distances tend to be perceived accurately in the real world. Previous work has shown that allowing participants to interact with the VE while receiving continual visual feedback can reduce this underperception. Judgments of virtual object size have been used to measure whether this improvement is due to the rescaling of perceived space, but there is disagreement within the literature as to whether judgments of object size benefit from interaction with feedback. This study contributes to that discussion by employing a more natural measure of object size. We also examined whether any improvement in virtual distance perception was limited to the space used for interaction (1–5 m) or extended beyond (7–11 m). The results indicated that object size judgments do benefit from interaction with the VE, and that this benefit extends to distances beyond the explored space.  相似文献   
96.
Pigeon concept formation: successive and simultaneous acquisition   总被引:2,自引:0,他引:2       下载免费PDF全文
Pigeons were trained to discriminate the presence of one or more human forms in displays projected on a panel above the response key. This task was mastered, although imperfectly, with successive and with simultaneous presentations of positive and negative instances. The course of acquisition of the discrimination was similar for the two training procedures. Animals were able to transfer the discrimination from the successive to the simultaneous situation. Various tests were carried out to control for artifactual cues on which the discrimination might have been based. The discrimination was maintained when new displays were presented, when reinforcement was omitted, and when displays were inverted 180°. Animals were also able to discriminate between pairs of displays that were identical, except that one member of the pair contained a human form. The research extends the techniques used by Herrnstein and Loveland (1964), and confirms their finding that pigeons can master the concept of “person-present” in a visual display.  相似文献   
97.
Harvey Siegel 《Synthese》1986,68(2):225-259
Conclusion There are many contemporary sources and defenders of epistemological relativism which have not been considered thus far. I have, for example, barely touched on the voluminous literature regarding frameworks, conceptual schemes, and Wittgensteinian forms of life. Davidson's challenge to the scheme/content distinction and thereby to conceptual relativism, Rorty's acceptance of the Davidsonian argument and his use of it to defend a relativistic position, Winchian and other sociological and anthropological arguments for relativism, recent work in the sociology of science, and Goodman's novel articulation of a relativism of worlds and of worldmaking, to mention just some of the contemporary loci of debate, all need to be addressed. So also do the plethora of relativistic arguments spawned by Kuhn and related literature in recent philosophy of science. Therefore, it cannot be said that there is no more to be said on behalf of epistemological relativism. Moreover, the positive task of delineating a defensible version of absolutism remains to be accomplished.Nevertheless, the defenses of relativism considered above do seem to have been successfully undercut. More specifically, the arguments for the incoherence of relativism are as compelling as ever, and have manifestly not been laid to rest by contemporary relativists. The basic Socratic insight that relativism is self-refuting, and so incoherent, remains a fundamental difficulty for those who would resuscitate and defend the ancient Protagorean doctrine or a modern variant of it.  相似文献   
98.
The relationship among working memory, mathematic ability, and the cognitive impairment of children with difficulties in mathematics was examined. A group of children with difficulties in mathematics (MD) was compared with a group of children with a normal level of achievement matched for vocabulary, age, and gender (N = 49). The children were required to perform a variety of working memory and short-term memory tasks that had been administered 1 year previously. Moreover, the children were asked to perform tasks designed to provide information about speed of articulation. The results suggest a general working memory deficit in children with MD, specifically in the central executive component of Baddeley's model and primarily in the ability to inhibit irrelevant information. However, the MD children were not impaired in speech rate and counting speed tasks, which mainly involve the role of the articulatory loop.  相似文献   
99.
100.
Much of the research that has examined the behavioral consequences of membership in mixed-gender work groups suggests that men are more participative and influential in task-related behavior. Drawing from elements of sociological, structural, and psychological perspectives, this study examined the effects of group gender composition and gender orientation of the group's task on patterns of emergent leadership behavior. Participants were assigned to male-dominated, female-dominated, or balanced-gender groups for the purpose of discussing and generating solutions for two business-related cases--each case emphasized either male-oriented or female-oriented expertise. The findings suggest that the proportional representation of men and women in a work group, along with the gender orientation of the group's task, can significantly influence the level of leadership behavior exhibited in group activity.  相似文献   
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