Osmotically driven drug delivery through remote-controlled magnetic nanocomposite membranes     

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   

Archipelagic rhetoric: remapping the Marianas and challenging militarization from “A Stirring Place”     

Tiara R. Na’puti 《传播与批判/文化研究》2019,16(1):4-25

Engaging critical rhetorical fieldwork in the Mariana Islands archipelago, this article destabilizes colonial naming projects and US federal control that dispossess island places from Indigenous peoples. On Euro-American and military maps, archipelagoes are depicted as distant, tiny, empty, or merely (is)lands for US geostrategic control. I argue for a remapping of the Marianas as expansive, oceanic sites of resistance to colonial cartographic violence and US militarization. Fieldwork in the Marianas demonstrates how Indigenous epistemologies function as archipelagic rhetoric enacted through a Chamoru sense of place. I examine these fluid relational connections to place and their implications for decolonization.  相似文献   

Informational Sources,Social Media Use,and Race in the Flint,Michigan, Water Crisis     

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   

Framing Refuge: Media,Framing, and Sanctuary Cities     

Benjamin Gonzalez O’Brien  Elizabeth Hurst  Loren Collingwood 《Mass Communication and Society》2019,22(6):756-778

The refugee sanctuary movement in the United States has shifted to include undocumented immigrants fleeing violence and economic strife. Given the negative tenor of coverage of undocumented immigration, and ties between framing and policy views on immigration, how the media frames sanctuary cities is likely to impact public perceptions of these cities and their policies. To assess media coverage of sanctuary policies, we analyzed articles from five national newspapers from 1980 to 2017 with both human content analysis and dictionary-based computational analysis. We find that framing around religion/morality and conflict has decreased, while stories focusing on crime and partisanship have increased. We discuss implications for public opinion and the likelihood that the American public will take their cues from media framing and elite discourse when it comes to sanctuary policies.  相似文献   

父母外出务工与留守子女辍学——基于CHNS调查数据的经验分析     

苏群  徐月娥  陈杰 《教育与经济》2015,(2):67-72

利用中国健康与营养调查(CHNS)数据,本研究对农村父母外出务工与留守子女初、高中阶段辍学行为之间的关系进行了实证分析。结果表明:父亲外出务工会显著降低留守子女初、高中阶段的辍学概率,母亲外出务工则会显著增加留守子女初中阶段的辍学概率。此外,免费义务教育政策的实施在较大程度上降低了留守子女的初、高中阶段的辍学概率;与那些父母受教育程度较低的留守子女相比,父母受教育程度越高的留守子女越不容易辍学;家庭子女数和机会成本会提高留守子女初中阶段辍学的概率。因此,为降低农村中学阶段子女辍学率,政府应当增加农村妇女当地就业机会以减少母亲外出的影响、推进户籍制度改革使随迁子女能获得同等的教育机会,并为高中阶段和多子女家庭提供教育补贴。  相似文献   

体育学院优秀散打运动队管理现状研究     

刘健  刘云安  高露露 《山东教育学院学报》2015,(2):104-108

本文采用文献资料法、问卷调查法、访谈法、数理统计法对我国体育院校优秀散打运动队的基本情况和运动员在思想、学习、训练以及生活管理中的现状进行分析探讨,希望能及时解决管理中存在的问题,从而为进一步提高我国散打运动队的管理提供服务。  相似文献   

The risks of ‘university speak’: relationship management and identity negotiation by mature students off campus     

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   

Establishing respectful educative relationships: a study of newly qualified teachers in Ireland     

Emmanuel O’Grady 《Cambridge Journal of Education》2015,45(2):167-185

Interpersonal respect is a fundamental aspect of relating to others. This is especially true for teachers, as cultivating relationships is implicit in effective teaching. This three-year qualitative study examines a developing understanding of respect for pre-service teachers that progresses on to their first year’s teaching to examine the influential factors on that understanding. These teachers’ pupils were also asked to comment on their perceptions of respect. The findings indicate that interpersonal respect in an educative relationship is influenced by the level of autonomy afforded pupils and minimising the power differential between teachers and pupils.  相似文献   

Education Assistant Support in Inclusive Western Australian Classrooms: Trialling a Screening Tool in an Australian Context     

John O’Rourke  John West 《International Journal of Disability, Development & Education》2015,62(5):531-546

Education assistants (EAs) who support students with disability in general education classrooms often find themselves in difficult situations. Caught in the firing line between their personal sense of duty, expectations of the classroom teachers, and the challenges that inclusion presents, their roles as primary support agents are anything but clear. In the following article the authors describe the findings from a modification of screening tool on the over-utilisation of paraprofessionals. The 16-item electronic survey focused on factors associated with EA support, conducted in a variety of Western Australian schools. The findings revealed that school community members such as EAs, classroom teachers, administrators and parents observed aspects of EA support that appear counter-productive towards more inclusive pedagogy.  相似文献   

Outside of School Matters: What We Need to Know in Urban Environments     

H. Richard Milner IV  Ira E. Murray  Abiola A. Farinde  Lori Delale-O’Connor 《Equity & Excellence in Education》2015,48(4):529-548

This article focuses on factors outside of school that we have identified from the established research literature as essential for educators to consider in supporting students in urban environments. We start by conceptualizing what it means for a school to be “urban.” Following this discussion, we describe four outside-of-school factors that emerge from the literature: (1) Understanding Student and Family Homelessness; (2) Understanding Geography and Social Contexts; (3) Understanding Policy and School Funding; and (4) Understanding Parental and Family Involvement. These factors are important to helping educators, especially pre- and in-service teachers, in their understanding of and, consequently, the practices they use to meet the needs of students in these social contexts. We conclude with recommendations for educational practice.  相似文献