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   

Intentional thought dynamics during exercise performed until volitional exhaustion     

Natàlia Balagué  Robert Hristovski  Sergi Garcia  Daniel Aragonés  Selen Razon  Gershon Tenenbaum 《Journal of sports sciences》2015,33(1):48-57

Using a non-linear approach, intentional dynamics of thoughts were examined during constant cycling performed until volitional exhaustion. Participants (n = 12) completed two sessions at 80% W_max. Their (1) intrinsic thought dynamics (i.e., no-imposed thoughts condition) and (2) intentional thought dynamics (i.e., imposed task-unrelated thoughts condition; TUT) were recorded and then classified into four categories: internal and external TUT (TUT-I, TUT-E) and external and internal task-related thoughts (TRT-E, TRT-I). The probability estimates for maintaining each thought category stable, the rate of switching from one category to another, and the entropy dynamics along the testing procedure were assessed and compared through time phase. Friedman ANOVA tests revealed a significant effect of effort increase on thought contents only in the imposed TUT test. While TUT-I probabilities decreased significantly (P < .001) as effort increased, TRT-I probabilities increased (P < .05). Moreover, the entropy to the entire thought dynamics increased at the outset of task performance and decreased upon approaching volitional exhaustion (P < .001). As time spent in constant effort increased, and volitional exhaustion approached, task relatedness (TUT, TRT), direction (internal, external), and entropy of thought contents changed unintentionally providing further evidence for a nonlinear dynamics of attention focus.  相似文献   

CRP,but not TNF-α or IL-6, decreases after weight loss in patients with morbid obesity exposed to intensive weight reduction and balneological treatment     

Danuta Ro??  Przemys?aw Adamczyk  Joanna Boinska  Robert Szafkowski  Irena Ponikowska  Katarzyna Stankowska  Barbara Góralczyk  Barbara Ruszkowska-Ciastek 《Journal of Zhejiang University. Science. B》2015,16(5):404-411

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Pawns in a Chess Game     

Gloria García González 《Media History》2015,21(4):412-425

The Spanish Service was established in June 1939, two months after the end of the civil war in Spain and shortly before the start of the Second World War. Its implementation was strongly affected by these conflicts in the context of new international relations. Therefore, this study of the Spanish Service during 1939–1945 allows not only a better understanding of the communicational strategies developed by the BBC, but also of the complex Anglo-Spanish relations and the important role played by the Spanish-language broadcasts therein. The study is mainly based on archival documents from the National Archives in London and memoirs.  相似文献   

Growing the Profession: Mentoring Undergraduates for Librarianship     

Connie Lamb  Brittany Hendricks  Quinn D. Galbraith 《College & Undergraduate Libraries》2015,22(2):123-148

Since 2007, Brigham Young University Library has provided a paid internship program for undergraduates that allows them to work with a librarian in an academic setting to help them decide if they wish to pursue a master's degree in Library Science. This article describes the internship program and provides results of surveys given to both interns and library mentors regarding their expectations and outcomes. In a new addition to the program, interns now meet with multiple librarians to gain a broad understanding of library work and how different library areas function together.  相似文献   

Into the gray: a modified approach to citation analysis to better understand research impact     

Shannon L. Sibbald  Jennifer C. D. MacGregor  Marisa Surmacz  C. Nadine Wathen 《Journal of the Medical Library Association》2015,103(1):49-54

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Destruction/reconstruction: preservation of archaeological and zoological research data     

Rebecca D. Frank  Elizabeth Yakel  Ixchel M. Faniel 《Archival Science》2015,15(2):141-167

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User experience of government documents: A framework for informing design decisions     

Leonardo Madariaga  Miguel Nussbaum  Faustino Marañón  Cristóbal Alarcón  María Alicia Naranjo 《Government Information Quarterly》2019,36(2):179-195

People still use documents in many everyday government processes. From tax payments to passport requests, citizens have to interact with low-interactivity information artifacts such as reports, maps and datasets, among many others. Despite efforts to improve information delivery in the public sector, effective information usage remains a critical topic of action and research. The user experience of government documents has rarely been assessed, despite them being regularly published and frequently used. Considering this, the two following research questions arise: 1) How can government documents be classified (or grouped) in terms of user experience? 2) How can the user experience of government documents be monitored over time in order to inform design decisions? Working with a public agency in Chile, we develop and test a classification and monitoring framework based on two online surveys (N?=?338 and N?=?298). We then propose a framework for understanding user experience of government documents in these three dimensions: interaction goal, volume of information and ease of understanding. Using a graphical representation to classify user experience provides greater visibility of the current status of information produced by a public organization. Furthermore, by monitoring the user experience of a government document at different times, organizations can understand the effect of their design decisions and improve their service quality by implementing user-centered processes.  相似文献   

Temporary Book Storage Using a Document Management Company     

Meredith Giffin  Kirsten Huhn  Andréa Harland 《资料收集管理》2019,44(1):46-68

Finding an appropriate temporary storage location for books and providing access to them is a significant challenge for libraries undergoing renovations. The current article describes the use of a document management company by an academic library to store 430,000 books for 8 months and provide a retrieval-on-demand service. Aspects covered include the selection of a commercial storage provider with its own retrieval service; details of the move to and from offsite storage; the integration of the service with library processes; communications and user feedback; book usage during the storage period; overall costs; and lessons learned from the experience.  相似文献   

Red pigment production by Penicillium purpurogenum GH2 is influenced by pH and temperature     

Méndez A  Pérez C  Montañéz JC  Martínez G  Aguilar CN 《Journal of Zhejiang University. Science. B》2011,12(12):961-968

The combined effects of pH and temperature on red pigment production and fungal morphology were evaluated in a submerged culture of Penicillium purpurogenum GH2, using Czapek-Dox media with d-xylose as a carbon source. An experimental design with a factorial fix was used: three pH values (5, 7, and 9) and two temperature levels (24 and 34 °C) were evaluated. The highest production of red pigment (2.46 g/L) was reached with a pH value of 5 and a temperature of 24 °C. Biomass and red pigment production were not directly associated. This study demonstrates that P. purpurogenum GH2 produces a pigment of potential interest to the food industry. It also shows the feasibility of producing and obtaining natural water-soluble pigments for potential use in food industries. A strong combined effect (p<0.05) of pH and temperature was associated with maximal red pigment production (2.46 g/L).  相似文献