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911.
It does take a village: nonfamilial environments and children's behavior   总被引:3,自引:0,他引:3  
Abstract - Family characteristics influence children's behavioral development, but so do variations in schools, neighborhoods, and communities. We documented extrafamilial environmental effects by fitting maximum likelihood models to questionnaire data collected from double dyads consisting of twins and their classmate controls. The classmate controls in each double dyad were genetic strangers living in separate households, but they shared school, neighborhood, and community environments with their yoked twin pair and with one another. At ages 11 to 12, the control classmates showed significant similarities in religious practices and smoking and drinking patterns, demonstrating that environmental influences outside the family affect children's behavioral development. Familial self-selection of residential neighborhoods may have contributed to these results, but direct effects of variation across communities, neighborhoods, and schools cannot be dismissed, and such effects warrant further study.  相似文献   
912.
When adults view a test disk embedded in a higher-luminance surround, the perceived lightness of the disk is largely determined by the surround-to-disk (S/D) luminance ratio (Wallach's ratio rule). Performance of 4-month-old infants tested with a forced-choice novelty-preference technique was consistent with predictions based on Wallach's ratio rule. This result suggests that the ability to extract and maintain information about local luminance ratios is present early in infancy. This ability is likely to contribute to the development of lightness constancy.  相似文献   
913.
The cochlear implant is best characterized as a device that provides access to the sound environment. The device enables the hearing pathway to respond to environmental and speech sounds, providing informational cues from the surroundings and from others that may escape visual detection. As the developmental effects of a profound hearing loss are multiple, cochlear implants have been applied to ever younger children in an attempt to promote a more normal level of developmental learning through audition. In deafness, transducer elements of the inner ear fail to trigger auditory nerve afferent nerves in the presence of sound input. However, large reserves of afferent fibers exist even in the auditory nerve of a profoundly deaf patient. Furthermore, these nerve fibers retain the ability to respond to prosthetic activation. Through developmental learning in the early, formative years, auditory centers of the brain appear capable of processing information from the implant to provide speech comprehension and oral language development. Multichannel implants have replaced original single channel designs. multichannel devices enable larger percentages of recipients to recognize the spoken word without visual cues because they provide spectral information in addition to temporal and intensity cues. Testing under conditions of auditory (implant)-only input reveals significant open-set speech understanding capabilities in more than 75% of children after three years of device use. The benefit provided by implants may vary with a number of conditions including: hearing history, age of deafness onset, age at implantation, etiology of deafness, linguistic abilities, and the presence of a motivated system of support of oral language development. Patient variables should be given individual consideration in judging candidacy for a cochlear implant and in planning rehabilitative and education services after surgery and activation of the device.  相似文献   
914.
Whose job is it to discover and manage patients' sexual concerns? If you believe that you have a role to play, just what is that role and how will you perform it? Sexual disorders are common, yet infrequently diagnosed. A willingness to inquire about sexual function is the most critical diagnostic step for clinicians. Once a problem is discovered, a systematic diagnostic process can uncover etiologic organic and psychogenic factors using customary diagnostic tools, including taking a psychosexual and medical history, comprehensive and focused physical examinations, psychological assessment instruments, laboratory tests, and special procedures.  相似文献   
915.
In a recent article, Howard H. Kendler (2002) criticized Kenneth B. Clark and the other social scientists who worked in Brown v. Board of Education for polluting their science with value judgments. This article argues that Kendler's critique is misguided because it conflates a policy judgment with a value judgment. In addition, Kendler inconsistently applied his own standard of objectivity when he examined in the social science used in Brown.  相似文献   
916.
This paper informally summarizes a two-day symposium held at the U.S. National Academy of Sciences in Washington, D.C., September 5–6, 2002. The issue was to what extent the progress of science and societal capacity for continued technological innovation are threatened by excessive protection of intellectual property. Excessive protection creates disadvantages not only for scientists and inventors but also for educators/students and for librarians/clientele. Speakers from a variety of disciplines and institutions agreed unanimously that scientific and technological progress is, indeed, under serious threat. Various opinions were expressed about the degree of threat, currently and prospectively, as well as what counter-measures are best suited to resist undue restrictions on creative uses of scientific and technical data and information. This summary is based entirely on the author’s notes from the symposium, and the commentary offered is his alone. My apologies to the speakers if this paper does not accurately reflect the primary intent of their presentations. The “Suggested Readings” offered at the end are not specific to the speakers’ statements but rather are offered as a general resource to aid further research. The definitive record of the symposium is planned to be available from the National Academies Press as a Proceedings publication in the summer of 2003. John Gardenier is an independent researcher, ethicist and science writer.  相似文献   
917.
This paper was presented at a seminar that outlined the work of the Surrey Ethics Forum. The Forum provides an opportunity for reflection by staff of the Federal University of Surrey and its Associated Institutions on ethical questions, the place of ethics in the curriculum and the role of ethics in the life of future graduates. The purpose of this paper is to argue that openness to the relationship between ethics and faith is itself an ethical task because both ethics and faith claim to protect human dignity and give meaning to the concept of "human flourishing". Analysis of the relationship between ethics, faith, flourishing and narrative can lead to clearer understanding of differences in ethical debates.  相似文献   
918.
919.
Research scientists are trained to produce specialised bricks of knowledge, but not to look at the whole building. Increasing public concern about the social role of science is forcing science students to think about what they are actually learning to do. What sort of knowledge will they be producing, and how will it be used? Science education now requires serious consideration of these philosophical and ethical questions. But the many different forms of knowledge produced by modern science cannot be covered by any single philosophical principle. Sociology and cognitive psychology are also needed to understand what the sciences have in common and the significance of what they generate. Again, traditional modes of ethical analysis cannot deal adequately with the values, norms and interests activated by present-day technoscience without reference to its sociological, political and economic dimensions. What science education now requires is ‘metascience’, a discipline that extends beyond conventional philosophy and ethics to include the social and humanistic aspects of the scientific enterprise. For example, students need to learn about the practices, institutions, career choices, and societal responsibilities of research scientists, and to rehearse in advance some of the moral dilemmas that they are likely to meet. They need also to realise that science is changing rapidly, not only in its research techniques and organisational structures but also in its relationships with society at large.  相似文献   
920.
The use of diagrams in analogical problem solving   总被引:2,自引:0,他引:2  
In four experiments, we examined the impact of perceptual properties on the effectiveness of diagrams in analogical problem solving, using variants of convergence diagrams as source analogues for the radiation problem. Static diagrams representing the initial problematic state (one large line directed at a target) and the final state for a convergence solution (multiple converging lines) were not accessed spontaneously but were often used successfully once a hint to consider the diagram had been provided. The inaccessibility of static diagrams was not alleviated by adding additional diagrams to represent intermediate states (Experiment 1), but spontaneous access was improved by augmenting static diagrams with a verbal statement of the convergence principle (Experiment 3). Spontaneous retrieval and noticing were increased markedly by animating displays representing converging forces and thereby encouraging encoding of the lines as indicating motion toward a target (Experiments 3 and 4). However, neither static nor animated diagrams were effective when the arrows were reversed to imply divergence rather than convergence (Experiment 2). The results indicate that when animation encourages the interpretation of a diagram as a helpful source analogue, it can greatly enhance analogical transfer.  相似文献   
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