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Gunn B.B. Kristensen Kristin Moberg Aakre Ann Helen Kristoffersen Sverre Sandberg 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):114-122
In laboratory medicine, several studies have described the most frequent errors in the different phases of the total testing process, and a large proportion of these errors occur in the pre-analytical phase. Schemes for registration of errors and subsequent feedback to the participants have been conducted for decades concerning the analytical phase by External Quality Assessment (EQA) organizations operating in most countries. The aim of the paper is to present an overview of different types of EQA schemes for the pre-analytical phase, and give examples of some existing schemes. So far, very few EQA organizations have focused on the pre-analytical phase, and most EQA organizations do not offer pre-analytical EQA schemes (EQAS). It is more difficult to perform and standardize pre-analytical EQAS and also, accreditation bodies do not ask the laboratories for results from such schemes. However, some ongoing EQA programs for the pre-analytical phase do exist, and some examples are given in this paper. The methods used can be divided into three different types; collecting information about pre-analytical laboratory procedures, circulating real samples to collect information about interferences that might affect the measurement procedure, or register actual laboratory errors and relate these to quality indicators. These three types have different focus and different challenges regarding implementation, and a combination of the three is probably necessary to be able to detect and monitor the wide range of errors occurring in the pre-analytical phase. 相似文献
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Education and Information Technologies - 3D printing is an emerging educational technology that is said to prepare learners for a more technologically designed world. In this review, 3D printing... 相似文献
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Ann Bailey James Funk David Lessley Chris Sherwood Jeff Crandall William Neale 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(5):678-700
ABSTRACT Professional American football games are recorded in digital video with multiple cameras, often at high resolution and high frame rates. The purpose of this study was to evaluate the accuracy of a videogrammetry technique to calculate translational and rotational helmet velocity before, during and after a helmet impact. In total, 10 football impacts were staged in a National Football League (NFL) stadium by propelling helmeted 50th percentile male crash test dummies into each other or the ground at speeds and orientations representative of concussive impacts for NFL players. The tests were recorded by experienced sports film crews to obtain video coverage and quality typically available for NFL games. A videogrammetry procedure was used to track the position and rotation of the helmet throughout the relevant time interval of the head impact. Compared with rigidly mounted retroreflective marker three dimensional (3-D) motion tracking that was concurrently collected in the experiments, videogrammetry accurately calculated changes in translational and rotational velocity of the helmet using high frame rate (two cameras at 240 Hz) video (7% and 15% error, respectively). Low frame rate (2 cameras at 60 Hz) video was adequate for calculating pre-impact translational velocity but not for calculating the translational or rotational velocity change of the helmet during impact. 相似文献
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Ann Lewis 《British Journal of Special Education》2004,31(1):3-9
The Gulliford Lecture 2003 was given by Professor Ann Lewis of the School of Education at the University of Birmingham. Professor Lewis's lecture, on which this article is based, focused on the process of listening to the views of children and, in particular, children with learning difficulties. Following the near-universal ratification of the United Nations (UN) Convention on the Rights of the Child, a plethora of recent initiatives, both in the UK and internationally, has encouraged professionals to access children's views about provision (educational, health-related, social and legal). A range of materials has been developed to support this process, often by, or in liaison with, children's charities. At the same time, research provides valuable insights into effective practice in exploring the views of children with learning difficulties. In this article, Ann Lewis reviews ten strategies for gathering the views of children and raises four challenges for the further development of policy and practice. She closes her argument with a call for greater rigour and critical evaluation in this crucial and demanding area. 相似文献
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Ann Gath 《International Journal of Disability, Development & Education》1993,40(3):167-174
The effect on families and the changes that occur in relation to a child with disability or independently are considered through the life span. The recent advances in prenatal screening, special care baby units and genetic counselling may increase fear of disability and have not decreased the incidence. As the rest of the family grow older, the disabled child goes through school years, faces adult life, often with disappointments, and remains having special needs and specific vulnerability until old age. 相似文献