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The number, amplitude, duration, and bout structure of isolation-induced ultrasonic vocalization (USV) of infant rats (Rattus norvegicus) were measured on postnatal Day 10. Measurements were made before and after a brief, 1-min, active interaction with their mother or before and after a "pick-up" control procedure. Consistent with prior studies, the number of USVs emitted was significantly increased in the period following the maternal reunion but not after the control procedure. The average amplitude of USVs was also greater following maternal reunion. Finally, analyses characterizing the bout structure of USV production indicated that the average bout size (i.e. number of USVs/bout) was increased severalfold following the reunion with the mother, accounting for the greater rate of USV production during the second isolation period.  相似文献   
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Spatial short-term memory for objects' locations was investigated in a spatial relocation task. During maintenance, dynamic visual noise or spatial tapping were administered as visual or spatial secondary tasks, respectively. Because memory for location should tap the visual component of working memory, a visual but not a spatial secondary task should impair location memory. In fact, neither of the tasks impaired memory (Experiment 1), although the expected dissociation between visual and spatial components was clearly confirmed for a spatio-temporal main task (Corsi test) (Experiment 2). We then contrasted location memory for pictures of objects and of nonsense figures under visual interference. Real objects were relocated much better than nonsense figures, and visual noise was again ineffective (Experiment 3). When spatial tapping was combined with the same material (Experiment 3a), again no influence on memory for locations of objects was observed and only a small influence on remembering nonsense figures. We suggest that the Corsi and the relocation VSWM-tasks use different memory mechanisms. The configuration of objects is reconstructed from perceptual records in an episodic buffer, provided by the same structures that enable visual memory after longer intervals. Rehearsal is not necessary for the persistence of these traces. In contrast, in the Corsi task remembering, a temporal sequence across homogeneous locations needs spatio-temporal marking and therefore active rehearsal of the locations by shifting spatial attention. A spatially demanding secondary task during retention interrupts this rehearsal.  相似文献   
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In his article ‘Better Communication Between Engineers and Managers: Some Ways to Prevent Many Ethically Hard Choices’1 Michael Davis analyzes the causes of the disaster in terms of a communications gap between management and engineers. When the communication between (representatives of) both groups breaks down, the organization is in (moral) trouble. Crucial information gets stuck somewhere in the organization prohibiting a careful discussion and weighing of all (moral) arguments. The resulting judgment has therefore little (moral) quality. In this paper I would like to comment on some of Michael Davis’s interesting and thought-provoking insights and ideas. A company which implements Davis’s recommendations at least shows some sensitivity to organizational moral issues. But it might miss the point that moral trouble can also result from a common understanding between managers and engineers. Organizational members sometimes tend to be myopic with regard to safety issues. This paper:
1.  describes different meanings of safety Managers and engineers, as Davis mentions, are sometimes willing to compromise quality, but do sacrifice safety. It is my contention that safety—in the sense of putting people’s lives on the line—will always be compromised, and that the discussion is about the ways to negotiate the risks./li
2.  focuses on a shared understanding of the situation and its implications for safety Using examples from a case study I did on behalf of a commercial airline,2 I will try to show that it is not always the communications gap between managers and engineers which poses a risk to the stakeholders involved, but a common understanding of the situation.
3.  focuses on a ‘timely concatenation of both active and latent failures’ as a cause for accidents I will argue that—in spite of our efforts to strengthen ethical consciousness and organizational practices—there will always be accidents. They are part of the human condition, since we cannot completely control the complexity of the situations in which they occur. One can, however, make them less costly.
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The aim of this study was to investigate route-learning ability in 67 children aged 5 to 11years and to relate route-learning performance to the components of Baddeley's model of working memory. Children carried out tasks that included measures of verbal and visuospatial short-term memory and executive control and also measures of verbal and visuospatial long-term memory; the route-learning task was conducted using a maze in a virtual environment. In contrast to previous research, correlations were found between both visuospatial and verbal memory tasks-the Corsi task, short-term pattern span, digit span, and visuospatial long-term memory-and route-learning performance. However, further analyses indicated that these relationships were mediated by executive control demands that were common to the tasks, with long-term memory explaining additional unique variance in route learning.  相似文献   
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With the completion of the Human Genome Project and the development of high throughput technologies, such as next-generation sequencing, the use of multiplex genetic testing, in which multiple genes are sequenced simultaneously to test for one or more conditions, is growing rapidly. Reflecting underlying heterogeneity where a broad range of genes confer risks for one or more cancers, the development of genetic cancer panels to assess these risks represents just one example of how multiplex testing is being applied clinically. There are a number of issues and challenges to consider when conducting genetic testing for cancer risk assessment, and these issues become exceedingly more complex when moving from the traditional single-gene approach to panel testing. Here, we address the practical considerations for clinical use of panel testing for breast, ovarian, and colon cancers, including the benefits, limitations and challenges, genetic counseling issues, and management guidelines.  相似文献   
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Multimedia instructional materials require learners to select, organize, and integrate information across multiple modalities. To facilitate these comprehension processes, a variety of multimedia design principles have been proposed. This study further explores the redundancy principle by manipulating the degree of partial redundancy between written and narrated content. Ninety high school students learned about cohesion via animated lesson videos from the Writing Pal intelligent tutoring system. Videos were crafted such that narrated and onscreen written content overlapped by 10%, 26%, or 50%. Across conditions, students gained significantly in their knowledge of cohesion‐building strategies and the effects of cohesion on writing quality. However, degree of redundancy did not influence learning gains. Additionally, although more‐skilled readers outperformed less‐skilled readers, reading skill did not interact with the degree of redundancy. These results provide evidence that a broad range of partially redundant multimedia materials may be viable instructional tools that benefit diverse learners. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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