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PURPOSE: This study describes the system architecture and user acceptance of a suite of programs that deliver information about newly updated library resources to clinicians' personal digital assistants (PDAs). DESCRIPTION: Participants received headlines delivered to their PDAs alerting them to new books, National Guideline Clearinghouse guidelines, Cochrane Reviews, and National Institutes of Health (NIH) Clinical Alerts, as well as updated content in UpToDate, Harrison's Online, Scientific American Medicine, and Clinical Evidence. Participants could request additional information for any of the headlines, and the information was delivered via e-mail during their next synchronization. Participants completed a survey at the conclusion of the study to gauge their opinions about the service. RESULTS/OUTCOME: Of the 816 headlines delivered to the 16 study participants' PDAs during the project, Scientific American Medicine generated the highest proportion of headline requests at 35%. Most users of the PDA Alerts software reported that they learned about new medical developments sooner than they otherwise would have, and half reported that they learned about developments that they would not have heard about at all. While some users liked the PDA platform for receiving headlines, it seemed that a Web database that allowed tailored searches and alerts could be configured to satisfy both PDA-oriented and e-mail-oriented users.  相似文献   
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Although much has been written about formal archival spaces, little scholarship has addressed the physical spaces of community archives. This paper asks: How do community members imagine the physical spaces that steward identity-based community archives? Based on focus groups with more than 54 community archives users at five different community archives sites across Southern California, this paper examines how members of marginalized communities conceive of the physical space inhabited by community archives representing their communities. The sites explored range from a prominent location on a university campus, to storefronts, strip malls, and small cinderblock buildings. Yet across sites, users spoke about community archives spaces as symbolic and affectively moving locations. Many users described their community archives site as a “home-away-from-home,” marked by intergenerational dialog and a profound sense of belonging. For other users, community archives sites were described as “politically generative spaces” which foster dialog and debate about identity, representation, and activism and enable the community to envision its future. And yet, while the very existence of community archives is political, many participants felt that the full political potential of these sites is not yet realized. By listening to the voices of the communities represented and served by community archives, our research both indicates that a shift is warranted in archival metaphors of space and reveals how community archives are personally and politically transformative spaces for the communities they represent and serve.  相似文献   
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The purpose of this study was to determine the sources of visual information used by highly skilled tennis players in anticipating their opponent's shots. In Experiment 1, motion analysis of the strokes showed that the relative motion between the racquet and forearm was different between the ground strokes and lobs, but there were no reliable kinematic differences when shot direction was varied. In Experiment 2, 12 skilled tennis players observed the opponent hitting strokes in a normal video or in a point-light display with different segments occluded. Players' anticipation accuracy was not degraded by the use of the point-light display. Occluding the racquet and forearm significantly reduced the participant's ability to determine the type of stroke produced.  相似文献   
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One of the most serious obstacles to accurate quantification of the underwater motion of a swimmer's body is image deformation caused by refraction. Refraction occurs at the water-air interface plane (glass) owing to the density difference. Camera calibration-reconstruction algorithms commonly used in aquatic research do not have the capability to correct this refraction-induced nonlinear image deformation and produce large reconstruction errors. The aim of this paper is to provide a thorough review of: the nature of the refraction-induced image deformation and its behaviour in underwater object-space plane reconstruction; the intrinsic shortcomings of the Direct Linear Transformation (DLT) method in underwater motion analysis; experimental conditions that interact with refraction; and alternative algorithms and strategies that can be used to improve the calibration-reconstruction accuracy. Although it is impossible to remove the refraction error completely in conventional camera calibration-reconstruction methods, it is possible to improve the accuracy to some extent by manipulating experimental conditions or calibration frame characteristics. Alternative algorithms, such as the localized DLT and the double-plane method are also available for error reduction. The ultimate solution for the refraction problem is to develop underwater camera calibration and reconstruction algorithms that have the capability to correct refraction.  相似文献   
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Abstract

Correspondence study represents the first and most persistent distance education format in American universities. Later called independent study, it enabled universities to disseminate instruction far beyond their campuses. Yet, national‐level leadership provided by the National University Continuing Education Association (NUEA) and its divisions has been relatively restrained. In contrast, leadership in the private correspondence school sector has been assertive, and sometimes even aggressive. The NUEA and its members shunned this approach, choosing instead to lead by persuasion and example. The NUEA developed standards of practice concerned primarily with replicating on‐campus teaching styles and values, rather than the promotion of distance education. With the abolition of its division structure, the NUEA's successor, the University Continuing Education Association (UCEA), has opted out of a leadership role in independent study. This paper concludes that the NUEA's initial attempt at leadership in distance education— while reasoned and principled—contained flaws that made failure inevitable.  相似文献   
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The purpose of this study was to examine: (a) the role of teacher talk in promoting peer interaction, (b) the adequacy of social IEP objectives to reflect children’s social functioning and guide provision of teacher talk, and (c) differences in children’s peer interaction and teacher talk in inclusive and segregated settings. Thirty children with disabilities and their teachers participated. Overall, we observed low rates of teacher talk thought to support peer interaction; however, when teachers verbally facilitated peer interaction, children were observed interacting more frequently with peers. Children’s social IEPs accurately reflected their current level of social functioning. However, the social IEPs appeared to fail to influence teacher intervention. Finally, children with disabilities in inclusive settings interacted with peers more than children in segregated settings, even though there was no significant difference in amount of teacher talk in the two settings.  相似文献   
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This study evaluated the classification accuracy of a second grade oral reading fluency curriculum‐based measure (R‐CBM) in predicting third grade state test performance. It also compared the long‐term classification accuracy of local and publisher‐recommended R‐CBM cut scores. Participants were 266 students who were divided into a calibration sample (n = 170) and two cross‐validation samples (n = 46; n = 50), respectively. Using calibration sample data, local fall, winter, and spring R‐CBM cut scores for predicting students’ state test performance were developed using three methods: discriminant analysis (DA), logistic regression (LR), and receiver operating characteristic curve analysis (ROC). The classification accuracy of local and publisher‐recommended cut scores was evaluated across subsamples. Only DA and ROC produced cut scores that maintained adequate sensitivity (≥.70) across cohorts; however, LR and publisher‐recommended scores had higher levels of specificity and overall correct classification. Implications for developing local cut scores are discussed.  相似文献   
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