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121.
122.
Objectives: The objective is to study how the staff who purchase health care services for a large national government accident-compensation system seek information on treatment effectiveness, how they assess the quality of that information, whether they question the information sources they choose, and how familiar they are with the key concepts of evidence-based health care (EBHC).Method: Staff (22 out of 34) of the health purchasing division of the New Zealand Accident Compensation Corporation (NZ ACC) were interviewed using eight preformatted questions to which they could provide open and multiple answers. Responses were subsequently codified into typologies for quantitative analysis.Results: Most respondents report that they assess the effectiveness of a treatment by accessing published information (nonhuman sources), by consulting others (human sources), or by both means. They assess the quality of information mostly by consulting others, and the second-highest proportion of responses state that they do not know how to evaluate the quality of information. No clear preference emerges with respect to the types of information needed to determine the effectiveness of treatments. The majority of the staff believes they can access information needed to determine treatment effectiveness through the Internet or information databases such as MEDLINE. Although most said they understand the key concepts of EBHC, only five out of twenty-two were able to accurately describe them.Conclusions: The findings suggest that there is a low level of awareness among the staff of the NZ ACC regarding the use of evidence and understanding of the key concepts of EBHC. Many surveyed staff members lack the skills or training to directly question information about effectiveness of a treatment. They have little idea of the information required to determine the effectiveness of a treatment, and the majority appears to lack the skills to evaluate the health care literature.  相似文献   
123.
An essential component in school accountability efforts is for assessments to be well-aligned with the standards or curriculum they are intended to measure. However, relatively little prior research has explored methods to determine statistical significance of alignment or misalignment. This study explores analyses of alignment as a special case of the generalized linear model (GLM). A general approach for such analyses is suggested, and examples are given for analyses with traditional alignment and GLM regression using data from two previously published studies. Results from the GLM are compared with ordinary least squares (OLS) regression. Findings show that the GLM method allows more informative analysis of differences between source documents than alignment indices alone, including determination of whether marginal discrepancies are statistically significant or not.  相似文献   
124.
A technique for microfluidic, pH modulated DNA capture and purification using chitosan functionalized glycidyl methacrylate monoliths is presented. Highly porous polymer monoliths are formed and subsequently functionalized off-chip in a batch process before insertion into thermoplastic microchannels prior to solvent bonding, simplifying the overall fabrication process by eliminating the need for on-chip surface modifications. The monolith anchoring method allows for the use of large cross-section monoliths enabling high flowrates and high DNA capture capacity with a minimum of added design complexity. Using monolith capture elements requiring less than 1 mm2 of chip surface area, loading levels above 100 ng are demonstrated, with DNA capture and elution efficiency of 54.2% ± 14.2% achieved.  相似文献   
125.
This study considers whether formally segmenting 4-year institutions by admissions selectivity affects the admission of transfer students. It develops a new measure, the student admission ratio, to compare the admission of transfer students in formally and highly segmented systems, informally and less segmented systems, and in formally unified systems. The study finds that the segmentation of systems by admissions selectivity does not adversely affect transfer admissions. The study concludes by positing that the formal structure of a system is not so important for student transfer as the processes for implementing transfer policy, and it considers the implications of this for practice.  相似文献   
126.
Abstract

The purpose of this study was (a) to assess lactate accumulation during isometric exercise, and to quantify the shifts in accumulation following isometric training; and (b) to relate any training-induced changes in lactate accumulation to reductions in resting blood pressure. Eleven male participants undertook isometric training for a 4-week period using bilateral-leg exercise. Training caused reductions in systolic, diastolic, and mean arterial resting blood pressure (of ?4.9 ± 6.3 mmHg, P = 0.01; ?2.6 ± 3.0 mmHg, P = 0.01; and ?2.6 ± 2.3 mmHg, P = 0.001 respectively; mean ± s). These were accompanied by changes in muscle activity, taken as electromyographic activity to reach a given lactate concentration (from 114 ± 22 to 131 ± 27 mV and from 136 ± 25 to 155 ± 34 mV for 3 and 4 mmol · L?1 respectively. Training intensity expressed relative to peak lactate was correlated with reduced resting systolic and mean arterial blood pressure. Training caused significant shifts in lactate accumulation, and reductions in resting blood pressure are strongly related to training intensity, when expressed relative to pre-training peak lactate. This suggests that higher levels of local muscle anaerobiosis may promote the training-induced reductions in resting blood pressure.  相似文献   
127.
Abstract

Although exercise training is unable to improve obesity-associated decreases in left ventricular (LV) diastolic function, as assessed using chamber function measurements, the effects on LV diastolic myocardial function, as assessed using tissue Doppler imaging (TDI), are uncertain. In 32 overweight (n = 11) or obese (n = 21), sedentary or recreationally active men and women (30–57 years), we assessed the effects of 6 weeks of exercise training either preceded (n = 16) or followed (n = 16) by a 6-week control period on TDI indices of LV diastolic function (e', e'/a' and E/e') (echocardiography). Diastolic function at baseline was comparable to that noted in overweight and obese participants from a community sample (n = 245), and 56% (n = 18) had e' values below the lower 95% CI of a lean and healthy cohort (n = 60) of the community sample. Exercise training increased peak oxygen consumption (27.4 ± 4.9 to 29.4 ± 5.8 mL · kg–1 · min–1, P = 0.0001), but had no effect on body mass index (P = 0.99). No changes in TDI indices of diastolic function were observed after exercise training in all the participants (e': P = 0.74, a': P = 0.98, e'/a': P = 0.85, E/e': P = 0.26), participants with abnormal e' values (n = 18)(e': P = 0.99, a': P = 0.96, e'/a': P = 0.91, E/e': P = 0.97) or obese participants (n = 21)(e': P = 0.67, a': P = 1.00, e'/a': P = 0.78, E/e': P = 0.11). In conclusion, exercise training, despite increasing cardiorespiratory fitness, is unable to improve obesity-associated decreases in LV diastolic myocardial function.  相似文献   
128.
ABSTRACT

This study investigated the effects of complete and partial sleep deprivation on multiple aspects of athletic performance. Ten males completed a cognitive function test, maximal handgrip strength, countermovement jump (CMJ) and a 15 min all out cycling test to assess aerobic performance. These tests were performed following 3 different sleep conditions; normal sleep (CON), a 4 hr sleep opportunity (PART) and complete sleep deprivation (DEP). Data were analysed using a Bayesian multi-level regression model to provide probabilities of impairment (p = %). Aerobic performance, CMJ and handgrip strength were impaired by 11.4% (p = 100%), 10.9% (p = 100%) and 6% (p = 97%) following DEP, while aerobic performance and CMJ were highly likely impaired by 4.1% (p = 90%) and 5.2% (p = 94%) following PART. Cognitive reaction time was not impacted by PART or DEP. In contrast the accuracy of responses was highly likely impaired by 2% (91) following DEP, while there was less certainty of impaired accuracy following PART (?1%, p = 73). Multiple aspects of physical and cognitive performance were impacted by sleep deprivation. The greatest detrimental effects were seen for aerobic performance and CMJ. Partial sleep deprivation equating to 4 hrs of sleep causes subtle, but potentially important negative impairments on athletic performance.  相似文献   
129.
This article sets out to argue that organisations can learn but that they cannot do so in their own right without infrastructural support. This article further examines the notion that individuals in organisations also require the cognitive participation of the organisation itself as a learning entity to learn. The close reliance and affiliation required between individuals and organisations to enable their learning from one another are discussed. In continuation of this, specific examples are provided through the industry sector of information systems development (ISD) projects to illustrate of how organisations can learn. Finally, the question of how one identifies organisational learning is analysed. Following on from the ISD and its use in the analogy of organisational learning, the article discusses an organisational empirical research project currently being undertaken by the authors, which utilises blogs. Though there are many potential organisational learning connotations associated with blogs, they could be perceived as a type of information system. The ongoing research being undertaken with the company using the blogs will attempt to identify indicators of learning at the individual, group and organisational levels. The significance of the issues explored in this article lies in the fact that it addresses an ISD approach to study how an organisation learns, and why this perspective is useful towards understanding the process of organisational learning. This article contributes to the organisational learning debate through an illustrative industry example of ISD projects. In doing so, we wish to argue that though individual learning can occur in ISD projects, the collective nature of projects primarily engenders the interpretive aspect of organisational learning. We further believe that it is the interactive nature of an ISD project that allows an organisation to learn in tandem with project members as exemplified through the stages of a project life cycle. We feel that this article contributes to the ISD and organisational learning literature in terms of linking both concepts together.  相似文献   
130.
Multi-label text categorization refers to the problem of assigning each document to a subset of categories by means of multi-label learning algorithms. Unlike English and most other languages, the unavailability of Arabic benchmark datasets prevents evaluating multi-label learning algorithms for Arabic text categorization. As a result, only a few recent studies have dealt with multi-label Arabic text categorization on non-benchmark and inaccessible datasets. Therefore, this work aims to promote multi-label Arabic text categorization through (a) introducing “RTAnews”, a new benchmark dataset of multi-label Arabic news articles for text categorization and other supervised learning tasks. The benchmark is publicly available in several formats compatible with the existing multi-label learning tools, such as MEKA and Mulan. (b) Conducting an extensive comparison of most of the well-known multi-label learning algorithms for Arabic text categorization in order to have baseline results and show the effectiveness of these algorithms for Arabic text categorization on RTAnews. The evaluation involves four multi-label transformation-based algorithms: Binary Relevance, Classifier Chains, Calibrated Ranking by Pairwise Comparison and Label Powerset, with three base learners (Support Vector Machine, k-Nearest-Neighbors and Random Forest); and four adaptation-based algorithms (Multi-label kNN, Instance-Based Learning by Logistic Regression Multi-label, Binary Relevance kNN and RFBoost). The reported baseline results show that both RFBoost and Label Powerset with Support Vector Machine as base learner outperformed other compared algorithms. Results also demonstrated that adaptation-based algorithms are faster than transformation-based algorithms.  相似文献   
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