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111.
Enabling persons with disabilities to prepare for and engage in gainful employment has become a priority concern in U.S. society. As a result, federal and state policymakers are adopting employment-related initiatives designed to enhance the employment rate of persons with disabilities. Policymakers need credible evidence in order to assess and reform these initiatives. This recognized need, however, begs the question of what constitutes 'credible evidence.' Of particular concern in the disability policy arena is the debate over the types of conclusion about employment rates that can and cannot be drawn from analyses of national survey data sets. This article connects standard research methodology concepts with the complexities of evaluating disability policy to help stakeholders appreciate the issues involved in this debate. This appreciation can help policymakers (1) recognize unwarranted cause-and-effect conclusions based solely on existing national survey data and (2) demand better data and stronger research designs to complement the potential over-reliance on correlational studies using problematic survey data to estimate policy impacts. To this end, the article concludes with a practical framework with a checklist for assessing the adequacy of research regarding the employment rate of persons with disabilities.  相似文献   
112.
The corpus callosum is the major neural pathway that connects homologous cortical areas of the two cerebral hemispheres. The nature of how that interhemispheric connection is manifested is the topic of this review; specifically, does the corpus callosum serve to communicate an inhibitory or excitatory influence on the contralateral hemisphere? Several studies take the position that the corpus callosum provides the pathway through which a hemisphere or cortical area can inhibit the other hemisphere or homologous cortical area in order to facilitate optimal functional capacity. Other studies suggest that the corpus callosum integrates information across cerebral hemispheres and thus serves an excitatory function in interhemispheric communication. This review examines these two contrasting theories of interhemispheric communication. Studies of callosotomies, callosal agenesis, language disorders, theories of lateralization and hemispheric asymmetry, and comparative research are critically considered. The available research, no matter how limited, primarily supports the notion that the corpus callosum serves a predominantly excitatory function. There is evidence, however, to support both theories and the possibility remains that the corpus callosum can serve both an inhibitory and excitatory influence on the contralateral hemisphere.  相似文献   
113.
Tracking multiple targets with multifocal attention   总被引:8,自引:0,他引:8  
Attention allows us to monitor objects or regions of visual space and select information from them for report or storage. Classical theories of attention assumed a single focus of selection but many everyday activities, such as video games, navigating busy intersections, or watching over children at a swimming pool, require attention to multiple regions of interest. Laboratory tracking tasks have indeed demonstrated the ability to track four or more targets simultaneously. Although the mechanisms by which attention maintains contact with several targets are not yet established, recent studies have identified several characteristics of the tracking process, including properties defining a 'trackable' target, the maximum number of targets that can be tracked, and the hemifield independence of the tracking process. This research also has implications for computer vision, where there is a growing demand for multiple-object tracking.  相似文献   
114.
Semantic features have provided insight into numerous behavioral phenomena concerning concepts, categorization, and semantic memory in adults, children, and neuropsychological populations. Numerous theories and models in these areas are based on representations and computations involving semantic features. Consequently, empirically derived semantic feature production norms have played, and continue to play, a highly useful role in these domains. This article describes a set of feature norms collected from approximately 725 participants for 541 living (dog) and nonliving (chair) basic-level concepts, the largest such set of norms developed to date. This article describes the norms and numerous statistics associated with them. Our aim is to make these norms available to facilitate other research, while obviating the need to repeat the labor-intensive methods involved in collecting and analyzing such norms. The full set of norms may be downloaded from www.psychonomic.org/archive.  相似文献   
115.
Senior capstone design and ethics: A bridge to the professional world   总被引:1,自引:1,他引:0  
A senior level capstone design experience has been developed and offered with a particular emphasis on many of the professional issues raised in Accreditation Board for Engineering and Technology (ABET) Engineering Criterion IV. The course has sought to develop student awareness of the ethical foundation of the engineering profession, the global and societal framework within which engineers practice, and the environmental impact on engineering. The capstone design course also focused upon improving the technical communications skills of the graduating senior class with both extensive instruction in writing and multiple workshops dealing with the art of making an effective oral presentation. The effectiveness of the design course was assessed using Kirkpatrick’s model for evaluating training programs. An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting, New Orleans, 2003.  相似文献   
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Volume Contents

Contents Volume 112 2003  相似文献   
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This study showed that couples' newlywed marriages and changes in their union over the first 2 years foreshadow their long-term marital fate after 13 years. Consistent with the enduring dynamics model, differences in the intensity of newlyweds' romance as well as the extent to which they expressed negative feelings toward each other predicted (a) whether or not they were happy 13 years later (among those who stayed married) and (b) how long their marriage lasted prior to separation (for those who divorced). The results provide little support for the idea that emergence of distress (e.g., increasing negativity) early in marriage leads to marital failure but instead show that disillusionment--as reflected in an abatement of love, a decline in overt affection, a lessening of the conviction that one's spouse is responsive, and an increase in ambivalence--distinguishes couples headed for divorce from those who establish a stable marital bond.  相似文献   
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