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Fatma Emel Kocak Bahadir Ozturk Ozben Ozden Isiklar Ozlem Genc Ali Unlu Irfan Altuntas 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(3):430-438
Introduction
Total 25-hydroxyvitamin D [25(OH)D] is the most reliable indicator of vitamin D status. In this study, we compared two automated immunoassay methods, the Abbott Architect 25-OH Vitamin D assay and the Roche Cobas Vitamin D total assay, with the liquid chromatography-tandem mass spectrometry (LC-MS/MS).Materials and methods
One hundred venous blood samples were randomly selected from routine vitamin D tests. Two of the serum aliquots were analyzed at the Abbott Architect i2000 and the Roche Cobas 6000’s module e601 in our laboratory within the same day. The other serum aliquots were analyzed at the LC-MS/MS in different laboratory. Passing-Bablok regression analysis and Bland-Altman plot were used to compare methods. Inter-rater agreement was analyzed using kappa (κ) analysis.Results
The Roche assay showed acceptable agreement with the LC-MS/MS based on Passing-Bablok analysis (intercept: -5.23 nmol/L, 95% CI: -8.73 to 0.19; slope: 0.97, 95% CI: 0.77 to 1.15). The Abbott assay showed proportional (slope: 0.77, 95% CI: 0.67 to 0.85) and constant differences (intercept: 17.08 nmol/L; 95% CI: 12.98 to 21.39). A mean bias of 15.1% was observed for the Abbott and a mean bias of -14.1% was observed for the Roche based on the Bland-Altman plots. We found strong to nearly perfect agreement in vitamin D status between the immunoassays and LC-MS/MS. (κ: 0.83 for Abbott, κ: 0.93 for Roche) using kappa analysis.Conclusion
Both immunoassays demonstrated acceptable performance, but the Roche Cobas assay demonstrated better performance than the Abbott Architect in the studied samples.Key words: 25-Hydroxyvitamin D, chromatography, immunoassay, methods, tandem mass spectrometry 相似文献3.
Olivier Chapelle Shihao Ji Ciya Liao Emre Velipasaoglu Larry Lai Su-Lin Wu 《Information Retrieval》2011,14(6):572-592
We study the problem of web search result diversification in the case where intent based relevance scores are available. A
diversified search result will hopefully satisfy the information need of user-L.s who may have different intents. In this
context, we first analyze the properties of an intent-based metric, ERR-IA, to measure relevance and diversity altogether.
We argue that this is a better metric than some previously proposed intent aware metrics and show that it has a better correlation
with abandonment rate. We then propose an algorithm to rerank web search results based on optimizing an objective function
corresponding to this metric and evaluate it on shopping related queries. 相似文献
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Mehmet Ali Ozturk Charles Debelak 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2008,54(1):83-97
The present article scrutinizes “the unique American vision of childhood” (UAVC) as a phenomenon undermining high academic expectations and good work ethics, and in turn, contributing to the generally low academic achievement of U.S. students compared to their counterparts in other advanced countries. It starts with a definition of UAVC, followed by a discussion of how influential it has been. The article goes on to state three reasons why UAVC is troublesome and misleading, especially in an era of global competition. Excuses devised by the proponents for UAVC’s adverse effects are also revealed. The article ends with recommendations for future research and a conclusion elaborating on the consequences of UAVC and the likelihood that other countries might adopt a similar mentality. 相似文献
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Popularity bias is an undesirable phenomenon associated with recommendation algorithms where popular items tend to be suggested over long-tail ones, even if the latter would be of reasonable interest for individuals. Such intrinsic tendencies of the recommenders may lead to producing ranked lists, in which items are not equally covered along the popularity tail. Although some recent studies aim to detect such biases of traditional algorithms and treat their effects on recommendations, the concept of popularity bias remains elusive for group recommender systems. Therefore, in this study, we focus on investigating popularity bias from the view of group recommender systems, which aggregate individual preferences to achieve recommendations for groups of users. We analyze various state-of-the-art aggregation techniques utilized in group recommender systems regarding their bias towards popular items. To counteract possible popularity issues in group recommendations, we adapt a traditional re-ranking approach that weighs items inversely proportional to their popularity within a group. Also, we propose a novel popularity bias mitigation procedure that re-ranks items by incorporating their popularity level and estimated group ratings in two distinct strategies. The first one aims to penalize popular items during the aggregation process highly and avoids bias better, while the second one puts more emphasis on group ratings than popularity and achieves a more balanced performance regarding conflicting goals of mitigating bias and boosting accuracy. Experiments performed on four real-world benchmark datasets demonstrate that both strategies are more efficient than the adapted approach, and empowering aggregation techniques with one of these strategies significantly decreases their bias towards popular items while maintaining reasonable ranking accuracy. 相似文献
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Homework is an important component of most physics courses. One of the functions it serves is to provide meaningful formative assessment in preparation for examinations. However, correlations between homework and examination scores tend to be low, likely due to unproductive student behavior such as copying and random guessing of answers. In this study, we attempt to model these two counterproductive learner behaviors within the framework of Item Response Theory in order to provide an ability measurement that strongly correlates with examination scores. We find that introducing additional item parameters leads to worse predictions of examination grades, while introducing additional learner traits is a more promising approach. 相似文献
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Nesrin Ozturk 《Educational studies》2017,43(3):247-264
For successful reading experiences in native and/or foreign/second language, individuals need to benefit from not only cognitive strategies but also metacognitive strategies. Although research found reading comprehension and performance increase following metacognitive trainings, such findings may not transfer into mainstream classrooms as easily for several reasons. This study, therefore, aimed to disseminate the phenomenon of teaching metacognition with an emphasis on teacher’s instrumental role during classroom learning. More specifically, it investigated language instructors’ metacognition and their self-reported competencies for teaching metacognition. It also examined whether and how self-reported competencies changed following a professional development (PD) module of teaching for metacognition. Utilising Metacognitive Awareness Inventory (MAI) and think aloud protocols for instructional planning, this study found most participants were either highly metacognitive or metacognitive individuals. It was also found that most participants were initially not knowledgeable about and/or competent in teaching metacognition. Following PD, highly metacognitive teachers developed authentic lesson plans manifesting metacognition instruction while metacognitive teachers adopted similar instructional designs presented during the PD. Besides, half of the participants appreciated teaching metacognitively following the PD. Finally, under the light of these findings, future research and policy adjustments were proposed. 相似文献
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Emre Özçelik 《Research Policy》2004,33(3):409-424
We examine the determinants of export performance of firms in the Turkish manufacturing industry. Prominent differences show up between innovator and non-innovator firms in terms of the impacts of such variables as firm size, advertisement intensities, ownership structures, and composition of employees. Importance of innovations and R&D activities, conduciveness of capital intensity, and insignificance of the real wage are meaningful as far as a rational international competition policy is concerned. Results are suggestive of a technology-oriented and capital-formative development path, if Turkey is to come up with the international competitive standards. 相似文献
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OBJECTIVE: To conceptualize the underlying causes of the medical neglect of children in a developing country and to provide suggestions for the management of neglect by pediatricians. METHODS: A case history of a 4-year-old boy from Turkey with neglect of the required treatment for acute lymphoblastic leukemia is used to examine the causes and management of medical neglect. Results: Although epidemiological studies on child neglect are lacking, this case exemplifies how in DEVELOPING countries, reasons for neglect or non-compliance with medical recommendations and the roles and actions taken by the health care and the social service systems may differ from western populations. Common to both western and developing countries, the characteristics of the child, family, and society may be reasons for medical neglect. However, cultural fatalistic beliefs profoundly present in the developing world may also contribute to the medical neglect of a child. Identification of the neglect, a comprehensive, multidisciplinary assessment emphasizing the strengths within the family and the society, and the determination of the pediatric team to act in the best interest of the child may result in resolution of the neglect even in circumstances where resources within systems are not sufficient. CONCLUSIONS: In developing countries, increased emphasis on child neglect, its prompt recognition and management within the pediatric profession as well as at a health care and social service system levels are needed to address this prevalent and potentially fatal child health problem. 相似文献
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The UK's Research Excellence Framework (REF) is a system that is intended to evaluate the quality of the research produced by higher education institutes (HEIs) in the UK in three areas: quality of research outputs; impact of this research beyond academia; and research environment. For the next REF, the funding bodies have reviewed the importance of the three assessment elements and decided to increase the weight of ‘impact’ to 25% (from 20% in REF2014) and decrease the weight of ‘outputs’ to 60% (from 65% in REF2014). This article first examines the relevance of some factors for the quality of impact submissions in REF2014 and finds that larger submissions and institutes with higher external research income received better impact scores in the REF. The article then examines the units of assessment (UoAs) and HEIs that benefitted from the inclusion of the impact agenda as part of REF2014 by examining the distribution of the quality-related research (QR) funding in the 2017–2018 period and finds that the QR funding gap among different UoAs tends to decrease but the gap among HEIs in most of the UoAs increased. With the increased importance of the impact agenda as a criterion for funding bodies, it is expected that research income will be concentrated in fewer universities in the future, with the increased importance of non-academic impact. This article also discusses some of the gaming strategies and long-term investment priorities that HEIs may engage in based on the new submission rules of the next REF. 相似文献