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71.
Gergely Simon Caroline Busch Marco A. B. Andrade Julien Reboud Jonathan M. Cooper Marc P. Y. Desmulliez Mathis O. Riehle Anne L. Bernassau 《Biomicrofluidics》2021,15(1)
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes. 相似文献
72.
V. B. Saputra S. K. Ong A. Y. C. Nee 《上海大学学报(英文版)》2014,(3):222-230
This paper presents a calibration method for parallel manipulators using a measurement system specially installed on an external fixed frame. The external fixed frame is important as an error reference for calibration in certain operations, such as in the configuration of a parallel manip- ulator functioning as a machine tool where the workpiece is fixed to a worktable. The pose of the end-effector is mea- sured using three digital indicators installed on the external fixed frame. To enable measurement, the end-effector is assumed to be a plane large enough that all digital indicators could touch. The error is defined as the difference between the theoretical and actual readings of the digital indicators. The geometric parameters of the parallel manipulator are optimized to minimize this error. This calibration method is low cost and feasible for compensating geometric parameter errors for a parallel manipulator. Optimal pose selection for the calibration is achieved using a swarm intelligence search algorithm. The method is implemented on a prototype of a six degrees-of-freedom (DOFs) Gough-Stewart platform constructed to function as a machine tool. 相似文献
73.
Ng Peggy M. L. Chan Jason K. Y. Lit Kam Kong 《Education and Information Technologies》2022,27(6):8129-8145
Education and Information Technologies - Online collaborative learning (OCL) has received significant attention, but the ultimate goal of adopting OCL is neglected, especially in higher education... 相似文献
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Education and Information Technologies - Advising students through their study plans is one of the essential steps towards academic success. The matching of students’ needs and courses... 相似文献
75.
Determination of clinically relevant content for a musculoskeletal anatomy curriculum for physical medicine and rehabilitation residents 下载免费PDF全文
Kristina Lisk John F. Flannery Eldon Y. Loh Denyse Richardson Anne M.R. Agur Nicole N. Woods 《Anatomical sciences education》2014,7(2):135-143
To address the need for more clinical anatomy training in residency education, many postgraduate programs have implemented structured anatomy courses into their curriculum. Consensus often does not exist on specific content and level of detail of the content that should be included in such curricula. This article describes the use of the Delphi method to identify clinically relevant content to incorporate in a musculoskeletal anatomy curriculum for Physical Medicine and Rehabilitation (PM&R) residents. A two round modified Delphi involving PM&R experts was used to establish the curricular content. The anatomical structures and clinical conditions presented to the expert group were compiled using multiple sources: clinical musculoskeletal anatomy cases from the PM&R residency program at the University of Toronto; consultation with PM&R experts; and textbooks. In each round, experts rated the importance of each curricular item to PM&R residency education using a five‐point Likert scale. Internal consistency (Cronbach's alpha) was used to determine consensus at the end of each round and agreement scores were used as an outcome measure to determine the content to include in the curriculum. The overall internal consistency in both rounds was 0.99. A total of 37 physiatrists from across Canada participated and the overall response rate over two rounds was 97%. The initial curricular list consisted of 361 items. After the second iteration, the list was reduced by 44%. By using a national consensus method we were able to objectively determine the relevant anatomical structures and clinical musculoskeletal conditions important in daily PM&R practice. Anat Sci Educ 7: 135–143. © 2013 American Association of Anatomists. 相似文献
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The University of Michigan opened a new medical library in July 1980. The five-story structure combines the library with a learning-resources center. Overall, the building has operated smoothly and has been well accepted. The combining of two facilities designed to support the teaching and learning objectives of the health sciences curriculum will ensure long-term cooperation between them. 相似文献
80.
Hertogh C Chamari K Damiani M Martin R Hachana Y Blonc S Hue O 《Journal of sports sciences》2005,23(9):937-942
In this study, we examined the effects of a prior run-up on intermittent maximal vertical jump performance. Seven regionally ranked male volleyball players volunteered to participate in the study. They performed three randomized tests: (1) six repeated intermittent maximal jumps (jump condition), (2) six repeated intermittent run-ups (run-up condition), and (3) six repeated run-ups followed by maximal jumps (run-up plus jump condition). All performances were assessed and blood lactate concentration and heart rate were measured before and after each of the tests. Mean ( +/- ) jump performance (64.7 +/- 2.3 cm) increased significantly (P = 0.02) over the course of the jump condition and was significantly higher (P < 0.001) than for the run-up plus jump condition (58.0 +/- 3.2 cm), which tended to decrease with repetition. Blood lactate concentration was significantly higher in the run-up plus jump condition (3.73 +/- 0.24 mmol . l(-1)) than in the jump (2.61 +/- 0.26 mmol . l(-1), P = 0.02) and run-up (2.86 +/- 0.18 mmol . l(-1), P = 0.03) conditions. The increase in heart rate was significantly higher both in the run-up plus jump condition (33 +/- 6 beats . min(-1), P = 0.05) and run-up condition (33 +/- 4 beats . min(-1), P = 0.02) than in the jump condition (21 +/- 3 beats . min(-1)). The results indicate that the addition of run-ups probably impeded performance in the repetition of vertical jumps. 相似文献