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101.
OBJECTIVES: Medicine must keep current with the research literature, and keeping current requires continuously updating the clinical knowledge base (i.e., references that provide answers to clinical questions). The authors estimated the volume of medical literature potentially relevant to primary care published in a month and the time required for physicians trained in medical epidemiology to evaluate it for updating a clinical knowledge base. METHODS: We included journals listed in five primary care journal review services (ACP Journal Club, DynaMed, Evidence-Based Practice, Journal Watch, and QuickScan Reviews). Finding little overlap, we added the 2001 "Brandon/Hill Selected List of Print Books and Journals for the Small Medical Library." We counted articles (including letters, editorials, and other commentaries) published in March 2002, using bibliographic software where possible and hand counting when necessary. For journals not published in March 2002, we reviewed the nearest issue. Five primary care physicians independently evaluated fifty randomly selected articles and timed the process. RESULTS: The combined list contained 341 currently active journals with 8,265 articles. Adjusting for publication frequency, we estimate 7,287 articles are published monthly in this set of journals. Physicians trained in epidemiology would take an estimated 627.5 hours per month to evaluate these articles. CONCLUSIONS: To provide practicing clinicians with the best current evidence, more comprehensive and systematic literature surveillance efforts are needed.  相似文献   
102.
This paper presents an experimental evaluation of several text-based methods for detecting duplication in scanned document databases using uncorrected OCR output. This task is made challenging both by the wide range of degradations printed documents can suffer, and by conflicting interpretations of what it means to be a duplicate. We report results for four sets of experiments exploring various aspects of the problem space. While the techniques studied are generally robust in the face of most types of OCR errors, there are nonetheless important differences which we identify and discuss in detail.  相似文献   
103.
The cross-sectional relationship between exercise training history and performance on a fluid intelligence test was examined. In addition, openness to experience was included as a potential trait-based contributor to predicting cognitive performance. Results supported past literature demonstrating that aerobically trained or active participants performed significantly better on the fluid intelligence task than aerobically untrained or inactive participants. Hierarchical regression analysis results revealed, as predicted, that openness to experience was a significant predictor of fluid intellectual performance. When entered into the hierarchical regression equation, openness to experience accounted for 16.0% of unique variance in Culture Fair Intelligence Test performance. By contrast, participants' exercise training history, which initially and significantly (p < .05) accounted for approximately 12.0% of the variance in cognitive performance, accounted for 5.0% (p > .05) after openness was entered. Participants were, on average, more open than inactive participants. Results are discussed in terms of the possible mechanisms aerobic exercise training and openness to experience share in regard to brain functioning and performance of fluid intelligence tasks. Future research is suggested that examines biological factors known to influence cognitive performance in exercise settings.  相似文献   
104.
Until recently, the traditional Inverted-U hypothesis had been the primary model used by sport psychologists to describe the arousal-performance relationship. However, many sport psychology researchers have challenged this relationship, and the current trend is a shift toward a more "multidimensional" view of arousal-anxiety and its effects on performance. In the current study, 104 college-age participants performed a simple response time task while riding a bicycle ergometer. Participants were randomly assigned to one of eight arousal groups (between 20 and 90% of heart rate reserve) and were told they were competing for a cash prize. Prior to the task, the Competitive State Anxiety Inventory-2 and Sport Anxiety Scale (SAS) were administered to assess the influence of cognitive and somatic anxiety. As hypothesized, regression analysis revealed a significant quadratic trend for arousal and reaction time. This accounted for 13.2% of the variance, F change (1, 101) = 15.10, p < .001, in performance beyond that accounted for by the nonsignificant linear trend. As predicted by the Inverted-U hypothesis, optimal performance on the simple task was seen at 60 and 70% of maximum arousal. Furthermore, for the simple task used in this study, only somatic anxiety as measured by the SAS accounted for significant variance in performance beyond that accounted for by arousal alone. These findings support predictions of the Inverted-U hypothesis and raise doubts about the utility theories that rely on differentiation of cognitive and somatic anxiety to predict performance on simple tasks that are not cognitively loaded.  相似文献   
105.
106.
The purpose of this study was to examine evidence for the validity of a stages of change measure of the Transtheoretical Model for exercise behavior. Participants were 152 university students (53.3% women, 71.6% Caucasian, M age = 19.18 years) who completed processes of change, self-efficacy, decisional balance, stages of change, and exercise behavior questionnaires as well as a maximal treadmill test. Participants in the action and maintenance stages had the highest strenuous (PC/C/P < A/M) and moderate (PC/C < A/M) self-reported exercise behavior. Those in the maintenance stage had the highest estimated aerobic fitness (PC/P < MA). The differences between the early stages (PC, C, and P) and the later stages (A and M) as described by the first function were primarily due to the behavioral process of change. The differences between the extreme stages (PC and M) and the middle stages (C, P, and A) were due to the experiential processes of change and the pros of decisional balance. The hypothesized patterns of stage differences were partially supported. Failure to obtain full support may have been due to methodological issues or inherent difficulties in detecting evidence for the validity of stages of change measures.  相似文献   
107.
108.
Collaborative information seeking often takes place in co-located settings; such opportunities may be planned (business colleagues meeting in a conference room or students working together in a library) or spontaneous (family members gathered in their living room or friends meeting at a café). Surface computing technologies (i.e., interactive tabletops) hold great potential for enhancing collaborative information seeking activities. Such devices provide engaging direct manipulation interactions, facilitate awareness of collaborators’ activities, and afford spatial organization of content. However, current tabletop technologies also present several challenges that creators of collaborative information seeking system must account for in their designs. In this article, we explore the design space for collaborative search systems on interactive tabletops, discussing the benefits and challenges of creating search applications for these devices. We discuss how features of our tabletop search prototypes TeamSearch, FourBySix Search, Cambiera, and WeSearch, illustrate different aspects of this design space.  相似文献   
109.
The main objectives of this study were (a) to elucidate young tennis players' use of music to manipulate emotional states, and (b) to present a model grounded in present data to illustrate this phenomenon and to stimulate further research. Anecdotal evidence suggests that music listening is used regularly by elite athletes as a preperformance strategy, but only limited empirical evidence corroborates such use. Young tennis players (N = 14) were selected purposively for interview and diary data collection. Results indicated that participants consciously selected music to elicit various emotional states; frequently reported consequences of music listening included improved mood, increased arousal, and visual and auditory imagery. The choice of music tracks and the impact of music listening were mediated by a number of factors, including extramusical associations, inspirational lyrics, music properties, and desired emotional state. Implications for the future investigation of preperformance music are discussed.  相似文献   
110.
While the number of Aboriginal and Torres Strait Islander students in higher education in Australia has doubled in recent years, the gap between their attainment and the attainment of other Australians has remained consistent. It is essential to elucidate the factors that promote Aboriginal and Torres Strait Islander students' academic success, not in order to justify the exclusion of these students from tertiary education, but to refine and develop curriculum and management strategies which promote their academic success. This study focuses on Aboriginal and Torres Straight Islander students' experiences in a diploma program offered in block mode, in order to better understand the ‘on-’ and ‘off-’ campus experiences which are related to academic success and the factors which challenge or enhance students' study. The research yields important findings related to students' motivations to enrol and their definitions of academic success; the challenges they experience in making the transition to tertiary study; the vulnerability of our students' determination to succeed; the effects of being in a program for Aboriginal and Torres Strait Islander students; and the ways in which minor challenges, if unresolved, can accumulate to interfere with students' study.  相似文献   
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