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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.
The framework for this paper is a recently developed theory of abstraction in context. The paper reports on data collected from one student working on tasks concerned with absolute value functions. It examines the relationship between mathematical constructions and abstractions. It argues that an abstraction is a consolidated construction that can be used to create new constructions. Newly formed constructions are fragile entities. In the course of consolidating a construction this student creates connections between the new construction and already established mathematical knowledge and develops a language to describe and guide mathematical actions related to the construction. The resulting abstraction is a more resilient form of the construction and the student is able to justify his assertions. The paper also examines issues in designing tasks to consolidate a construction. 相似文献
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Fatih Yazıcı Tercan Yıldırım 《Paedagogica Historica: International Journal of the History of Education》2018,54(4):433-446
Nation-states needed various ideological apparatuses when they wanted to eliminate traditional loyalties to the pre-modern era and establish a new superordinate identity. As frequently emphasised in conceptual discussions, two elements among these ideological apparatuses come to the fore: historiography and education. While social values that create a national identity have been constructed by historiography continuously from the past to the present, it aims at spreading such values through education. History education at the intersection of these two concepts has occupied a privileged place in the nation-building process. The most concrete examples of this phenomenon are the developments experienced in the context of history teaching in Turkey from 1923 to 1938, also known as the early republican period. The present study, using history textbooks, analyses changes in history teaching and expectations of it between 1923 and 1938, which were the most active years of the nationalisation period in Turkey. The findings of this study indicate that the historiography of the early republican period adopted an anthropology-based understanding in line with the conjuncture between the two world wars and that, in accordance with this understanding, a national identity with ethnic, religious, and political dimensions was intended to be promulgated through history teaching. 相似文献
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Julie A. Edmunds Fatih Unlu Elizabeth Glennie Lawrence Bernstein Lily Fesler Jane Furey 《Journal of research on educational effectiveness》2017,10(2):297-325
Developed in response to concerns that too few students were enrolling and succeeding in postsecondary education, early college high schools are small schools that blur the line between high school and college. This article presents results from a longitudinal experimental study comparing outcomes for students accepted to an early college through a lottery process with outcomes for students who were not accepted through the lottery and enrolled in high school elsewhere. Results show that treatment students attained significantly more college credits while in high school, and graduated from high school, enrolled in postsecondary education, and received postsecondary credentials at higher rates. Results for subgroups are included. 相似文献
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Erdal Binboğa Serdar Tok Fatih Catikkas Senol Guven Senol Dane 《Journal of sports sciences》2013,31(9):982-988
Abstract We investigated the effect of verbal encouragement on maximal voluntary contraction (MVC) level of the triceps surae muscle group. Our secondary focus was to examine whether the effect of verbal encouragement on MVC level varies as a result of conscientiousness. While the participants performed plantar flexion, MVCs of the triceps surae muscle group were measured using rectified and smoothed surface electromyography (rsEMG) during the absence and presence of verbal encouragement. Participants completed questions from the Five Factor Personality Inventory concerning conscientiousness and were divided into high- and low-conscientiousness groups according to a median split. The sample included 30 female and 53 male elite athletes. In the entire cohort, there was no significant difference in MVCs with and without verbal encouragement. When the sample was partitioned by conscientiousness scores, verbal encouragement led to a significant increase in MVC in the low-conscientiousness group, whereas verbal encouragement led to a non-significant decrease in MVC in the high-conscientiousness group. Percentage change in MVC across experimental conditions was significantly different between the groups, with a 9.72% increase during verbal encouragement of the low-conscientiousness group, and a 2.47% decrease during verbal encouragement of the high-conscientiousness group. 相似文献
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Arslan-Ari Ismahan Crooks Steven M. Ari Fatih 《Journal of Science Education and Technology》2020,29(5):666-676
Journal of Science Education and Technology - This study explored the effects of prior knowledge and cueing on the learning (retention, transfer, and matching) and mental effort of learners who... 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
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Kristin E. Porter Sean F. Reardon Fatih Unlu Howard S. Bloom Joseph R. Cimpian 《Journal of research on educational effectiveness》2017,10(1):138-167
A valuable extension of the single-rating regression discontinuity design (RDD) is a multiple-rating RDD (MRRDD). To date, four main methods have been used to estimate average treatment effects at the multiple treatment frontiers of an MRRDD: the “surface” method, the “frontier” method, the “binding-score” method, and the “fuzzy instrumental variables” method. This article uses a series of simulations to evaluate the relative performance of each of these four methods under a variety of different data-generating models. Focusing on a two-rating RDD (2RRDD), we compare the methods in terms of their bias, precision, and mean squared error when implemented as they most likely would be in practice—using optimal bandwidth selection. We also apply the lessons learned from the simulations to a real-world example that uses data from a study of an English learner reclassification policy. Overall, this article makes valuable contributions to the literature on MRRDDs in that it makes concrete recommendations for choosing among MRRDD estimation methods, for implementing any chosen method using local linear regression, and for providing accurate statistical inferences. 相似文献