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Do students today know less than their parents or grandparents did as students? Are they being academically outclassed by students of other nations? Or have ideologically driven policy makers painted an unnecessarily negative picture of student achievement?  相似文献   
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Chaos theory, informational needs, and natural disasters   总被引:2,自引:0,他引:2  
This study applies chaos theory to a system-wide analysis of crisis communication in a natural disaster. Specifically, we analyze crisis communication during the 1997 Red River Valley flood in Minnesota and North Dakota. This flood, among the worst in modern American history, consumed entire metropolitan areas, displacing thousands of people. The conditions and decisions leading to the disaster, and the subsequent reactions are retraced. Communication related to river crest predictions (fractals), the shock at the magnitude of the crisis (cosmology episode), novel forms of reorganizing (self-organization), and agencies that aided in establishing a renewed order (strange attractors) are evaluated. Ultimately, we argue that preexisting sensemaking structures favoring rationalized, traditional views of a complex system led officials to make inappropriately unequivocal predictions and ultimately diminished the effectiveness of the region's crisis communication and planning.  相似文献   
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The roles of academic health sciences librarians are continually evolving as librarians initiate new programs and services in response to developments in computer technology and user demands. However, statistics currently collected by libraries do not accurately reflect or measure these new roles. It is essential for librarians to document, measure, and evaluate these new activities to continue to meet the needs of users and to ensure the viability of their professional role. To determine what new measures should be compiled, the authors examined current statistics, user demands, professional literature, and current activities of librarians as reported in abstracts of poster sessions at Medical Library Association annual meetings. Three new categories of services to be measured are proposed. The first, consultation, groups activities such as quality filtering and individual point-of-need instruction. The second, outreach, includes activities such as working as liaisons, participating in grand rounds or morning report, and providing continuing education. The third area, Web authoring, encompasses activities such as designing Web pages, creating online tutorials, and developing new products. Adding these three measures to those already being collected will provide a more accurate and complete depiction of the services offered by academic health sciences librarians.  相似文献   
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The purpose of this study was to determine test-retest reliability for the 1-mile, 3/4-mile, and 1/2-mile distance run/alk tests for children in Grades K-4. Fifty-one intact physical education classes were randomly assigned to one of the three distance run conditions. A total of 1,229 (621 boys, 608 girls) completed the test-retests in the fall (October), with 1,050 of these students (543 boys, 507 girls) repeating the tests in the spring (May). Results indicated that the 1-mile run/walk distance, as recommended for young children in most national test batteries, has acceptable intraclass reliability (.83 less than R less than .90) for both boys and girls in Grades 3 and 4, has minimal (fall) to acceptable (spring) reliability for Grade 2 students (.70 less than R less than .83), but is not reliable for children in Grades K and 1 (.34 less than R less than .56). The 1/2 mile was the only distance meeting minimal reliability standards for boys and girls in Grades K and 1 (.73 less than R less than .82). Results also indicated that reliability estimates remained fairly stable across gender and age groups from the fall to spring testing periods, with the exception of the noticeably improved values for Grade 2 students on the 1-mile run/walk test. Criterion-referenced reliability (P, percent agreement) was also estimated relative to Physical Best and Fitnessgram run/walk standards. Reliability coefficients for all age group standards were acceptable to high (.70 less than P less than .95), except for Fitnessgram standards for 5-year-old girls on the 1-mile test for both fall and spring and for 6-year-old boys and girls on the 1-mile test administered in the spring.  相似文献   
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