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A. Zaher S. Li K. T. Wolf F. N. Pirmoradi O. Yassine L. Lin N. M. Khashab J. Kosel 《Biomicrofluidics》2015,9(5)
Implantable drug delivery systems can provide long-term reliability, controllability, and biocompatibility, and have been used in many applications, including cancer pain and non-malignant pain treatment. However, many of the available systems are limited to zero-order, inconsistent, or single burst event drug release. To address these limitations, we demonstrate prototypes of a remotely operated drug delivery device that offers controllability of drug release profiles, using osmotic pumping as a pressure source and magnetically triggered membranes as switchable on-demand valves. The membranes are made of either ethyl cellulose, or the proposed stronger cellulose acetate polymer, mixed with thermosensitive poly(N-isopropylacrylamide) hydrogel and superparamagnetic iron oxide particles. The prototype devices'' drug diffusion rates are on the order of 0.5–2 μg/h for higher release rate designs, and 12–40 ng/h for lower release rates, with maximum release ratios of 4.2 and 3.2, respectively. The devices exhibit increased drug delivery rates with higher osmotic pumping rates or with magnetically increased membrane porosity. Furthermore, by vapor deposition of a cyanoacrylate layer, a drastic reduction of the drug delivery rate from micrograms down to tens of nanograms per hour is achieved. By utilizing magnetic membranes as the valve-control mechanism, triggered remotely by means of induction heating, the demonstrated drug delivery devices benefit from having the power source external to the system, eliminating the need for a battery. These designs multiply the potential approaches towards increasing the on-demand controllability and customizability of drug delivery profiles in the expanding field of implantable drug delivery systems, with the future possibility of remotely controlling the pressure source. 相似文献
136.
Ashleigh M. Day Sydney O’Shay-Wallace Matthew W. Seeger Shawn P. McElmurry 《Communication Studies》2019,70(3):352-376
Safe, clean water is necessary for health and well-being. Water issues affect minority and vulnerable populations at disproportionate rates, including the poor and racial and ethnic minorities. An investigation of the relationships of race, social media use, and informational sources during the municipal water crisis in Flint, Michigan, reflects an instrumental view of communication and uses and gratifications theory in this study. Data from 208 Flint residents in 2016 indicated that African American respondents favored interpersonal networks and resources and were more likely than other racial groups to obtain current information about the water crisis via Instagram. Preferred channels and sources to receive additional crisis information varied on the basis of race. 相似文献
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Neil O’Boyle 《International Studies in Sociology of Education》2015,25(2):93-111
Research finds that participation in higher education is generally empowering for mature students but that it can also create tensions in their off-campus relationships. This article reports on findings from an ongoing study of the experiences of mature students at university in Ireland and draws from interviews with 15 such students in the final year of their studies. Following similar research by Baxter and Britton in the UK, the article considers how mature students experience and represent changes in identities and social relationships brought about by entry to higher education. Specifically, the article focuses on the risks associated with using newly acquired academic language (or ‘university speak’) off campus. The findings reported here complement existing research and offer support for Baxter and Britton’s suggestion that mature students often experience compartmentalisation and fragmentation in their self-identities. 相似文献
138.
Laura Crane Jade Davies Anne Fritz Sarah O’Brien Alison Worsley Anna Remington 《British Educational Research Journal》2022,48(1):22-48
Changes to special educational needs and disability (SEND) legislation in England were implemented in 2014. Here, we evaluate the impact of these changes from the perspective of 80 autistic young people aged 16–25 years. Using an online survey and/or interviews, we examined young people’s views on three key principles of the SEND reforms: the help and support provided to them; whether they were given a say in the choices and support that they were offered; and their satisfaction with their educational journeys and outcomes. The results paint a mixed picture. Our sample of young people reported varied experiences regarding the help and support they received, and how much of a say they had regarding the choices and support available to them. The types of schooling they accessed played a role here: young people in mainstream schools highlighted particular challenges in accessing appropriate support, while many young people in special schools said they felt well supported. Parental advocacy was crucial for all young people, as was having key ‘champions’ in the form of teachers who really knew them well. The need for the development of general life and self-advocacy skills was apparent, however, especially in preparing the young people for life after school. Encouragingly, most of our participants were generally happy with their current situation, despite identifying several areas for further improvement. Overall, the results highlight the importance of listening to—and learning from—autistic young people, throughout their educational journeys and especially as they transition to adulthood. 相似文献
139.
Pereira Brenda Braga Silva Luciano Fernandes dos Santos Janaina Roberta 《Science & Education》2022,31(1):1-20
Science & Education - The purpose of this study is to identify and analyze meanings that the term complexity assumes in Brazilian theses and dissertations in the field of environmental... 相似文献
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