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61.
Ajay Kumar D. H. Shah M. G. R. Rajan U. R. Thakare S. M. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):159-164
An external quality assessment was conducted to assess the performance of various laboratories for RIA of thhyroid related
hormones in two phases. In the first phase thirty five laboratories participated. At the end of first phase a meeting cum
workshop was organised to discuss the results of first phase, difficultires faced by the participants and pinpoint the short
oming. A second phase was then initiated with an objective of improvement in the performance, if any, where twelve samples
from four pools were distributed to twenty four laboratories who participated for the second phase. The overall return of
the results increased significantly from 71.8% (1586/2208) for the first phase to 92.4% (732/792) for the second phase. The
inter laboratory %CV for T3, T4 and TSH were lower during the second phase (30.6%, 19.0% and 31.6% respectively) as compared to those observed during first
phase (36.3%, 22.7% and 52.8% respectively). Similarly, there was an improvement in reproducibility of ALTM as %CV for T3, T4 and TSH decreased from 6.0%, 9.8% and 13.4% respectively to 4.5%, 4.6% and 8.5% respectively. The individual performances
of the participating laboratories viz. bias, variability of bias and imprecision also showed a trend towards improvement as
percent laboratories having desirable or acceptable results for T3, T4 and TSH increased from 10.7%, 60.7% and 0.0% respectively to 20.8%, 66.7% and 22.2% respectively. External quality assessment
thus appears to be beneficial in assessing the performane of a laboratory in comfparison with other laboratories and indeed
helps in improving the performance. 相似文献
62.
Tunable pores (TPs) have been used for resistive pulse sensing of 1 μm superparamagnetic beads, both dispersed and within a magnetic field. Upon application of this field, magnetic supraparticle structures (SPSs) were observed. Onset of aggregation was most effectively indicated by an increase in the mean event magnitude, with data collected using an automated thresholding method. Simulations enabled discrimination between resistive pulses caused by dimers and individual particles. Distinct but time-correlated peaks were often observed, suggesting that SPSs became separated in pressure-driven flow focused at the pore constriction. The distinct properties of magnetophoretic and pressure-driven transport mechanisms can explain variations in the event rate when particles move through an asymmetric pore in either direction, with or without a magnetic field applied. Use of TPs for resistive pulse sensing holds potential for efficient, versatile analysis and measurement of nano- and microparticles, while magnetic beads and particle aggregation play important roles in many prospective biosensing applications. 相似文献
63.
Inger Andersen Naoko Ishii Thomas Brooks Cynthia Cummis Gustavo Fonseca Astrid Hillers Nicholas Macfarlane Nebojsa Nakicenovic Kevin Moss Johan Rockstr?m Andrew Steer Dominic Waughray Caroline Zimm 《国家科学评论(英文版)》2021,(7):12-15
The 2015 Paris Agreement to keep global warming well below 2℃above pre-industrial levels and aim towards limiting warming to 1.5℃marked a wa-tershed in planetar... 相似文献
64.
Kevin H. Ashford-Rowe Marnie Holt 《美中教育评论》2011,(3):317-322
The "emerging educational institutional decision-making matrix" is developed to allow educational institutions to adopt a rigorous and consistent methodology of determining which of the myriad of emerging educational technologies will be the most compelling for the institution, particularly ensuring that it is the educational or pedagogical but not the technological imperative that drives the technology integration agenda. The matrix is designed to be used after some initial research into an emerging technology. Once a technology is put through the matrix, a member of options are available: (1) shelving the technology; (2) putting the technology on hold and maintaining a watching brief until the technology matures in the market; and (3) researching the product further by conducting a trial or placing in testing sandpit. After further research, the technology can be tested as a pilot to determine how well or otherwise, the technology works within the institution. If an emerging technology has more than one product associated with it, a second and third step in the matrix has been developed, and the second step assigns a rating to each of the categories within the matrix. With many products containing similar features, a third step has been developed to compare products on a feature level. 相似文献
65.
Signature pedagogies [Shulman, L. 2005. “Signature pedagogies in the professions.” Daedalus 134 (3): 52–59.] are a focus of teacher educators seeking to improve teaching and teacher education. The purpose of this paper is to present a preliminary common language of signature pedagogies for teacher professional development (PD). In all, 24 papers from the study of physical education PD projects with clearly articulated pedagogical objectives and documentation on achieving those objectives were included in the analysis. In total 479 teachers and 48 facilitators across the US and Europe were interviewed and/or surveyed. Three discrete PD signature pedagogies holding potential to enhance teacher growth and learning within the context of PD were identified: critical dialogue (process of acquiring knowledge through communicative interactions), public sharing of work (testing out practices in classrooms and share ideas with larger audiences), and communities of learners (collective learning around a shared concern or a passion). It is our hope in providing the beginnings of a common vocabulary for pedagogies of teacher professional learning we have encouraged additional steps toward developing signature pedagogies for learning across different PD settings and content areas. 相似文献
66.
Jakob D. Jensen Katheryn Christy Melinda Krakow Kevin John Nicole Martins 《The Journal of educational research》2016,109(6):666-674
Leisure reading behavior is a key predictor of educational success. Transportability is a trait that determines how likely an individual is to become involved in a story, and past research has suggested that involvement may be related to leisure reading behavior. However, available measures of transportability have not been validated with children or related to leisure reading. To address this gap, children 9–13 years old (N = 136) completed a revised version of the Transportability Scale. A 13-item version of the scale was found to be unidimensional, reliable, and predictive of 6% of the variance in leisure reading (above and beyond sex, age, reading ability, and student performance). Transportability was also related to genre preference and several interesting sex differences emerged. The Transportability Scale provides researchers with a psychometrically sound measure of narrative involvement to advance research on leisure reading. 相似文献
67.
68.
Cantlon JF Davis SW Libertus ME Kahane J Brannon EM Pelphrey KA 《Learning and individual differences》2011,21(6):672-680
In an effort to understand the role of interhemispheric transfer in numerical development, we investigated the relationship between children's developing knowledge of numbers and the integrity of their white matter connections between the cerebral hemispheres (the corpus callosum). We used diffusion tensor imaging (DTI) tractography analyses to test the link between the development of the corpus callosum and performance on symbolic and non-symbolic numerical judgment tasks. We were especially interested in the interhemispheric connections of parietal cortex in 6-year-old children, because regions of parietal cortex have been implicated in the development of numerical skills by several prior studies. Our results revealed significant structural differences between children and adults in the fibers of the corpus callosum connecting the left and right parietal lobes. Importantly, these structural differences were predictive of individual differences among children in performance on numerical judgment tasks: children with poor numerical performance relative to their peers exhibited reduced white matter coherence in the fibers passing through the isthmus of the corpus callosum, which connects the parietal hemispheres. 相似文献
69.
This paper examines music education’s legitimation of values as a means of preparing students for entry into the new ‘knowledge society’ of the People’s Republic of China in a global age. It explores the ways in which values education relates to the teaching of both musical and non‐musical meanings in the dual context of nationalism and globalization, and discusses some problems that values education faces in school music classrooms. It examines the ways in which globalization has pressured values education into resolving the apparent contradiction between national identity and national unity in the ever‐changing play of Chinese history and politics. It concludes with a discussion of how music education might juggle three pairs of apparently contradictory relationships in the curriculum: between contemporary cultural and social values on the one hand, and traditional Chinese and Communist ideologies on the other; between collectivism and individualism; and between national and global cultures. 相似文献
70.
Hongli Li C. Kevin Fortner Xiaoxuan Lei 《School Effectiveness & School Improvement》2013,24(2):258-278
In this study, we examined relationships between the use of test results and US students’ math, reading, and science performance in the Programme for International Student Assessment (PISA) 2009. Based on a literature review, we hypothesized that the 16 items in the PISA school questionnaire, which are related to the use of test results, can be categorized according to 4 factors. We validated this hypothesized factor structure using a confirmatory factor analysis and then obtained composite scores for each factor. As revealed by a multilevel analysis, when student and school demographic variables were controlled for, using test results to hold schools accountable to authority and the public was significantly positively related to students’ performance across all 3 subjects. No statistically significant relationship, however, was detected between students’ performance and the following uses of test scores: informing parents of their children’s performance, providing information for instructional purposes, and evaluating teachers and principals. 相似文献