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Implantable drug delivery devices are becoming attractive due to their abilities of targeted and controlled dose release. Currently, two important issues are functional lifetime and non-controlled drug diffusion. In this work, we present a drug delivery device combining an electrolytic pump and a thermo-responsive valve, which are both remotely controlled by an electromagnetic field (40.5 mT and 450 kHz). Our proposed device exhibits a novel operation mechanism for long-term therapeutic treatments using a solid drug in reservoir approach. Our device also prevents undesired drug liquid diffusions. When the electromagnetic field is on, the electrolysis-induced bubble drives the drug liquid towards the Poly (N-Isopropylacrylamide) (PNIPAM) valve that consists of PNIPAM and iron micro-particles. The heat generated by the iron micro-particles causes the PNIPAM to shrink, resulting in an open valve. When the electromagnetic field is turned off, the PNIPAM starts to swell. In the meantime, the bubbles are catalytically recombined into water, reducing the pressure inside the pumping chamber, which leads to the refilling of the fresh liquid from outside the device. A catalytic reformer is included, allowing more liquid refilling during the limited valve''s closing time. The amount of body liquid that refills the drug reservoir can further dissolve the solid drug, forming a reproducible drug solution for the next dose. By repeatedly turning on and off the electromagnetic field, the drug dose can be cyclically released, and the exit port of the device is effectively controlled. 相似文献
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Norzaini Azman Ibrahim Che Omar Aida Suraya Md Yunus Ahmad Nurulazam Md Zain 《牛津教育评论》2016,42(1):71-88
The expansion and transformation of Malaysian universities have generated major changes in the nature of academic employment and the structure of academic promotion in higher education institutions. These changes have considerable implications, in particular for the policy and practice of academic promotion in the public universities. We argue that despite sharing one common grade and salary system, distinct and significant differences exist in the academic promotion systems of the public universities. Drawing on one recent study on the academic promotion process in Malaysian public universities to contextualise our discussion, this paper highlights the complexity in the promotion process in these institutions. It also discusses and articulates the attendant issues and challenging aspects of the academic promotion process. We argue that the interrelated issues and challenges, and certain academic practices and habits stemming from the pressure to gain a promotion are pervasive, and that they affect the academic value system and work culture. We conclude by asserting the importance of applying a consistent standard for promotion within a single salary system and that the academic promotion system in the public universities should ultimately affirm and communicate core academic values, and also aim at obtaining evidence of excellent accomplishments. 相似文献
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In this quasi-experimental study, we describe the effect of showing dissection videos on first-year medical students' performance in terms of test scores during a gross anatomy course. We also surveyed students' perception regarding the showing of dissection videos. Two hundred eighty-seven first-year medical students at Rawalpindi Medical College in Pakistan, divided into two groups, dissected one limb in first term and switched over to the other limb in the second term. During the second term, instruction was supplemented by dissection videos. Second-term anatomy examination marks were compared with first-term scores and with results from first-year medical students in previous years. Multiple linear regression analysis was performed, with term scores (continuous, 0-200) as the dependent variable. Students shown dissection videos scored 1.26 marks higher than those not shown. The relationship was not statistically significant (95% CI: -1.11, 3.70; P = 0.314). Ninety-three percent of students favored regular inclusion of dissection videos in curriculum, and 50% termed it the best source for learning gross anatomy. Seventy-six percent of students did not perform regular cadaver dissection. The most frequent reason cited for not performing regular dissection was high student-cadaver ratio. Dissection videos did not improve performance on final examination scores; however, students favored their use. 相似文献
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Renawi Abdulrahman Alnajjar Fady Parambil Medha Trabelsi Zouheir Gochoo Munkhjargal Khalid Sumaya Mubin Omar 《Education and Information Technologies》2022,27(4):4753-4770
Education and Information Technologies - Monitoring students' attention and engagement levels in classrooms are critical in promoting an interactive teaching process. Therefore, in addition to... 相似文献
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ABBAS T.A. OMAR M.S. 《浙江大学学报(A卷英文版)》2007,8(5):793-796
A suitable simple optical cryostat for optical, magneto-optical, electrical and thermo-electrical measurements was designed. It is suitable for use in a magnetic pool gap as narrow as less than 1 cm. Throughout a long period of time, the heat diffusion process of the cryostat can be easily operated at slow increase in sample temperature in a range 1.25 K/min at 200 K that will be reduced gradually to 0.66 K at room temperature. Liquid nitrogen was used to cool down the temperature. During the operation, the change in the measured energy gap of a semiconductor sample and other physical parameters resulting from the change of temperature can be corrected through the temperature coefficient of that parameter at the corresponding temperature. The cryostat was successfully used for all experiments mentioned above to measure the properties of a single crystal of GaP (Gallium Phosphate) semiconductor. 相似文献
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Omar S. López 《Community College Journal of Research & Practice》2013,37(1):86-90
The Voluntary Framework of Accountability (VFA) launched in 2011 is the first national system of community college accountability. Sponsored by the American Association of Community Colleges (AACC) in collaboration with the Association of Community College Trustees and the College Board, the VFA will shortly report to the public on measures of student progress and learning outcomes and on measures of workforce, economic, and community development. The author of this paper proposes that AACC move beyond community college accountability toward creating and sustaining, among college administrators, a common culture of VFA data use to investigate best practices for institutional improvement. To advance this proposition, the discourse presented centers on a proof-of-concept model. The study uses longitudinal data to illustrate its potential for community college administrators to identify best practices for improving institutional performance in first-year college retention. 相似文献