1,721,014 research outputs found
Recommended from our members
Transport phenomena and pharmacokinetics of anti-HIV microbicide drug delivery
Get PDFMicrobicides are agents that can be applied to vaginal mucosal surfaces with the goal of blocking the transmission of sexually transmitted pathogens including HIV. They can be formulated in various delivery vehicles, including gels, creams, lotions, tablets or films. A recent study in South Africa has confirmed, for the first time, that a vaginal gel formulation of the antiretroviral drug Tenofovir, when topically applied, significantly inhibits sexual HIV transmission to women. However the gel for this drug, and anti-HIV microbicide vehicles in general, have not been designed using an understanding of how their spreading and retention in the vagina govern successful drug delivery. Elastohydrodynamic lubrication theory can be applied to model spreading of microbicide gels and films. This should incorporate the full rheological behavior, including how rheological properties change due to contact with, and dilution by, ambient vaginal fluids. A Carreau-like non-Newtonian model is adopted as a rheological model. The effects of three important factors, i.e., dilution by vaginal fluid, a yield stress of the gel and swelling, are investigated. Dilution accelerates the coating flow by creating a slippery region near the vaginal wall akin to a dilution boundary layer. The concept of a yield stress fluid is attractive because such a material may tend to stay in place after coating vulnerable surfaces. We show that the lubrication approximation, which eases the efforts of design, may be applied to the elastic wall-squeezing problem for a prototype gel with yield stress. For the important presence of significant swelling of the gel by absorption of vaginal fluid, the model indicates more rapid coating. Then we study films that can be preferable over gels due to several reasons in many parts of the world. A model is developed for transient swelling and spreading of a film, and subsequent distribution of an active drug throughout the vaginal lumen. We investigate the effects of combination of many factors.The theory developed here improves our understanding of the biophysics of microbicide gel and film flows in vivo. Ultimately, this dissertation contributes to a methodology that provides objective evaluations of microbicide gel and film performance and in the design of new, improved vehicles
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Microfluidics for microalgal biotechnology
No full textOzdalgic, Berin/0000-0003-0113-541X; Kiraz, Alper/0000-0001-7977-1286; Ustun, Merve/0000-0002-3883-4065; Tasoglu, Savas/0000-0003-4604-217X; Haznedaroglu, Berat Zeki/0000-0002-0081-8801; Rahmani Dabbagh, Sajjad/0000-0001-8888-6106Microalgae have expanded their roles as renewable and sustainable feedstocks for biofuel, smart nutrition, biopharmaceutical, cosmeceutical, biosensing, and space technologies. They accumulate valuable biochemical compounds from protein, carbohydrate, and lipid groups, including pigments and carotenoids. Microalgal biomass, which can be adopted for multivalorization under biorefinery settings, allows not only the production of various biofuels but also other value-added biotechnological products. However, state-of-the-art technologies are required to optimize yield, quality, and the economical aspects of both upstream and downstream processes. As such, the need to use microfluidic-based devices for both fundamental research and industrial applications of microalgae, arises due to their microscale sizes and dilute cultures. Microfluidics-based devices are superior to their competitors through their ability to perform multiple functions such as sorting and analyzing small amounts of samples (nanoliter to picoliter) with higher sensitivities. Here, we review emerging applications of microfluidic technologies on microalgal processes in cell sorting, cultivation, harvesting, and applications in biofuels, biosensing, drug delivery, and nutrition.Alexander von Humboldt-StiftungAlexander von Humboldt Foundation; Marie Sklodowska-Curie Individual Fellowship award [101003361]; Royal Academy Newton-Katip Celebi Transforming Systems Through Partnership Award [120N019]; TUBITAK 2232 International Fellowship for Outstanding Researchers AwardTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [118C391]Alexander von Humboldt-Stiftung, Grant/Award Number: Research Fellowship for Experienced Researchers; Marie Sklodowska-Curie Individual Fellowship award, Grant/Award Number: 101003361; Royal Academy Newton-Katip Celebi Transforming Systems Through Partnership Award, Grant/Award Number: 120N019; TUBITAK 2232 International Fellowship for Outstanding Researchers Award, Grant/Award Number: 118C39
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
