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891.
B. G. C. Maisonneuve T. Honegger J. Cordeiro O. Lecarme T. Thiry D. Fuard K. Berton E. Picard M. Zelsmann D. Peyrade 《Biomicrofluidics》2016,10(2)
With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks. 相似文献
892.
Bharti Jain J. Kumarasamy Chandrakala Gholve Savita Kulkarni M. G. R. Rajan 《Indian journal of clinical biochemistry : IJCB》2017,32(2):193-199
Serum thyroglobulin (Tg) and thyroid stimulating hormone (TSH) measurements have evolved as important analytes for monitoring the prognosis of patients with differentiated thyroid cancer, post-thyroidectomy. Individual analyte immunoassay is the current practice in clinical pathology, but the simultaneous assay for all relevant analytes for a given disease, can reduce assay costs, improve patient compliance and give the clinician more information for an unequivocal diagnosis. Microarray immunoassay (MI) can achieve this goal and, hence, we have developed and validated a immuno-radiometric MI for quantitation of serum TSH and Tg by using highly micro-porous polycarbonate (PC) track-etched membranes (TEM) to immobilize the monoclonal anti-TSH and polyclonal anti-Tg antibodies in ~1 mm diameter spots. Non-competitive immunoassays were performed using mixture of 125I labeled monoclonal anti-TSH and anti-Tg antibodies. Phosphorimager was used to quantify the bound radioactivity. TSH and Tg were detected with detection limit of 0.07 µIU/ml and 0.13 ng/ml respectively, which is lower than the clinically required cut-off level. The assay showed: acceptable intra-assay precision within 20 % and recovery in the range of 76–111.2 %. MI compared well with the established immunoradiometric assay (IRMA) with r = 0.98, p < 0.01 (n = 41). No cross-reactivity was seen between the immobilized antibodies. Although two hormones are addressed in this report, MI using PC TEM and isotopic/non-isotopic tracers has the potential for highly automated multiplexed analysis. 相似文献
893.
Rachel K. Katch Samantha E. Scarneo William M. Adams Lawrence E. Armstrong Luke N. Belval Julie M. Stamm Douglas J. Cas 朱为模审校 《体育科研》2018,(2):31-46
参加有组织的体育运动和休闲活动存在发生严重伤病甚至死亡的内在风险。虽然造成体育运动或体育活动中猝死的原因有很多,但运动医学和循证标准治疗方面的进展已使临床医生得以更有效地预防、发现和治疗可能致死的伤患。随着研究与技术不断发展进步,当前的治疗标准正在不断发展以更好地改善患者的治疗效果。本文提出了10个与运动和体育活动中猝死的主要原因及其治疗手段有关的关键问题,未来开展的研究将提高运动员和休闲运动爱好者参与运动的安全度。当前证据表明,如采取正确的预防策略或最佳治疗方案,绝大多数的死亡案例是可以避免的。 相似文献
894.
Nataly Loizidou‐Ieridou Jackie Masterson J. Richard Hanley 《Journal of Research in Reading》2010,33(3):247-262
The aim of the present study was to examine the spelling development of Greek‐speaking children in the early school grades. Although Greek orthography is regular for reading, it is much less transparent as far as spelling is concerned. Spelling development was investigated using a word spelling task designed to explore the effects of word length, familiarity and spelling regularity. One hundred and fifty normally developing primary school children living in Cyprus took part in the study. Results suggest that the children employed both phonological and lexical strategies in spelling Greek words. Results indicated that sub‐lexical procedures were more marked for younger children, whereas lexical processing was employed more widely by older children. The findings are interpreted in terms of stage developmental models. 相似文献
895.
896.
Keith J. Topping 《Learning and Instruction》2010,20(4):339-343
Peer assessment is very various in its implementation. Six studies of peer assessment are reviewed, four of them in higher education. A literature review is followed by five empirical studies. Strengths and weaknesses of each study are considered and issues are raised. Variables in peer assessment needing further exploration are extricated – in sample definition, specification of type of peer assessment, organisational nature of the intervention, and the measures which are used to evaluate change. It is suggested that further experimental and quasi-experimental studies are necessary to contrast one or two of these variables at a time. 相似文献
897.
Scaling is the process of constructing a score scale that associates numbers or other ordered indicators with the performance of examinees. Scaling typically is conducted to aid users in interpreting test results. This module describes different types of raw scores and scale scores, illustrates how to incorporate various sources of information into a score scale, and introduces vertical scaling and its related designs and methodologies as a special type of scaling. After completion of this module, the reader should be able to understand the relationship between various types of raw scores, understand the relationship between raw scores and scale scores, construct a scale with desired properties, evaluate an existing score scale, understand how content and standards information are built into a scale, and understand how vertical scales are developed and used in practice. 相似文献
898.
Dale J. Vidmar 《Research Strategies》2005,20(3):135-148
Reflective peer coaching is a formative model for improving teaching and learning by examining intentions prior to teaching, then reflecting upon the experience. The goal of reflective peer coaching is to promote self-assessment and collaboration for better teaching and ultimately better learning. There are obvious benefits to colleagues collaborating and sharing ideas, thoughts, and observations. However, many models of assessing teaching effectiveness focus on summative evaluation in which colleagues observe each other once or twice a year and fill out institutional evaluation forms. Rarely do colleagues engage in formative conversations about teaching that are guided by the instructor's personal goals and objectives. Reflective peer coaching necessitates a ten-minute planning conversation prior to the actual lesson and a ten-minute reflective conversation after the lesson. These conversations happen regularly and frequently to build self-awareness and self-assessment of the personal craft of teaching. The following article outlines the dynamics of the reflective peer coaching process as a formative assessment model that leads to better learning through improved teaching. 相似文献
899.
900.