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51.
An automated, disk-based, enzyme-linked immunosorbent assay (ELISA) system is presented in this work. Magnetic beads were used as the antibody carriers to improve the assay sensitivity and shorten the reaction time. The magnetic module integrated on the system is capable of controlling the magnetic beads to either move in the incubation stage or immobilize at a specific location during washing stage. This controlling mechanism utilizes a passive controlling approach so that it can be performed through disk spinning without the need of active control from external devices. The movement of the magnetic beads was investigated and the optimal rotational speed was found to be related to the ratio of the processing time to the cycle time of the magnetic beads. Comparing to ELISA conducted on microtiter plates, similar test results could be achieved by the disk-based ELISA but the entire protocol can be finished automatically within 45 min with much less reagent consumption. 相似文献
52.
In this report, we describe in detail a microfluidic analyzer, which is able to conduct blood coagulation tests using whole blood samples. Sample preparation steps, such as whole blood aliquoting and metering, plasma separation, decanting, and mixing with reagents were performed in sequence through microfluidic functions integrated on a disk. Both prothrombin time (PT) and activated partial thromboplastin time (aPTT) were carried out on the same platform and the test results can be reported in 5 min. Fifty clinical samples were tested for both PT and aPTT utilizing the microfluidic disk analyzer and the instrument used in hospitals. The test results showed good correlation and agreement between the two instruments. 相似文献
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Ju‐Ling Shih Hui‐Chun Chu Gwo‐Jen Hwang Kinshuk 《British journal of educational technology : journal of the Council for Educational Technology》2011,42(3):373-394
In recent years, digital learning has been converting from e‐learning to m‐learning because of the significant growth of wireless and mobile computing technologies. Students can learn any time and any where with mobile devices. Consequently, context‐aware ubiquitous learning (u‐learning) is emerging as a new research area. It integrates wireless, mobile and context awareness technologies in order to detect the situation of the learners and provide more seamless adaptive support in the learning process. In this paper, a context‐aware u‐learning environment is developed for learning about campus vegetation in elementary schools based on an innovative approach by employing repertory grid method in designing learning content. In addition, we probe the feasibility of context‐aware u‐learning in courses by soliciting feedback from the students and teachers through interviews and questionnaires. The findings reveal that the environment is capable of enhancing students’ motivation and learning effectiveness. Moreover, it is also capable of reducing the teaching load while enabling better control of class order. 相似文献
56.
石铸 《中国科学院研究生院学报》1987,25(1):39-49
About 22 species of the genus Scorzonera L. are so far known to occur in China.
Among them, S. pamirica Shih is described as new and 3 species, S. tau-sahyz Lipsch. et Bosse,
S. pubescens DC. and S. transiliensis M. Pop., are new records to China. Four names in the
literature are reduced to synonyms,and some wrong identications in Chinese botanical literature
are pointed out in this work. Some species with considerable variation in morphology, such as,
S. pseudodivaricata Lipsch. and S. sinensis Lipsch. ex Krasch., are also discussed here. 相似文献
57.
中国菊科菜蓟族植物研究(Ⅱ) 总被引:1,自引:0,他引:1
石铸 《中国科学院研究生院学报》1984,22(5):386-396
本文是对国产菜蓟族两个属研究的一个小结。一个是蓟属(Cirsium Mill. Ecmend.Scop.),将全部国产蓟属49种植物分隶排列在8个组中,其中3个组为新成立的组,1个组为新的组合。记载了9个新种,1个新组合种,4个种为中国分布新记录。将过去学者们发表的组、种 及变种等各级上的65个名称处理为新异名,检查出错误鉴定8处,对变异较大的种给予了说明和讨论。另一个是刺膜菊属(Alfredia Cass.),记载了一个新种。 相似文献
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