1,720,955 research outputs found
3D-Printed Transdermal Microneedles for Allergen Immunotherapy
No full textColor poster with text, images, charts, and graphs.Allergen immunotherapy or “allergy shots” are delivered as fast-acting intravenous (IV) injections given to patients suffering from chronic allergies. However, in rural settings, patients must travel long distances for a single injection, significantly adding to patient costs, and costs to an already over-burdened health-care system. We hypothesized that minimally invasive, painless, self-administered 3D (three-dimensional) printed microneedles could be a better alternative in these scenarios and could be provided in conjunction with tele-medicine. For this study, 3D printed microneedles were printed using Formlabs stereolithography (SLA) printers and clear V4 material. Different parameters were calibrated including layer thickness, size, shape, material, and needle orientation, to enable dermal puncture with minimal breakage. Our results show that a Pyramid Needle Model (needle array: 1(L)x1(W)x0.5(H) cm; needle dimensions: 200(L)x200(W)x800(H) µm; 500µm (spacing); 1µm (tip diameter); 45° angle; 0.025mm layer-thickness) was the best microneedle model produced through our experiments. Microscopy and porcine skin puncture testing confirmed the functionality of these needles in the laboratory. Taken together, our results showcase the feasibility of fabrication of transdermal microneedles through 3D printing, providing a fast and effective solution for self-administered painless drug delivery. Future work will focus on improving microneedle design to enable allergy-drug loading and delivery.University of Wisconsin--Eau Claire Office of Research and Sponsored Program
Engineered and Biomimetic Caviar Analogs as a Sustainable Food Source
No full textColor poster with text, charts, photographs, and graphs.Caviar refers to processed salted roe obtained from large fish, and it often requires the sacrifice of a pregnant female. With the increasing global human population, the demand for caviar is rapidly growing, threatening wildlife fish populations everywhere. While many improved versions of caviar analogs have been created, they are unable to mimic natural caviar color, texture, structure, popping (while chewing), and taste. The goal of this project is to develop a scalable method for developing caviar analogs using engineering techniques. For this study, we investigated the use of sodium alginate and calcium chloride (CaCl₂) in the production of engineered caviar analogs that replicate the texture, appearance, and sensory characteristics of natural caviar. Alginate solutions of different concentrations (1-5%) and needles of different gauges were calibrated to achieve structural integrity and mimicry of caviar analog size. Furthermore, CaCl₂ was frozen in liquid nitrogen before soaking in a bath of alginate to form caviar analogs with an outer crusty shell and a softer center, to re-create the popping-effect. Future work will include incorporating our findings within a microfluidic device for a scalable way of producing engineered caviar analogs, furthering the broader pursuit of sustainable food design.University of Wisconsin--Eau Claire Office of Research and Sponsored Program
Controlled release of brain derived neurotrophic factor to promote neuron survival following chronic electrode implantation
Get PDFChronic electrode implantation in the brain leads to the formation of a glial scar surrounding the implantation site. The glial scar, when formed, severely inhibits the long term in-vivo functionality of neural electrodes. Studies in the past have tried coating the neural electrodes using polymers with or without bioactive agents. However none report any success in alleviating the glial scar or show improvement in electrode recording capability. Previous studies have suggested the use of neurotrophin delivery from electrode coatings to promote neuron survival and improve electrode biocompatibility. In the current work, the feasibility of delivering Brain Derived Neurotrophic Factor (BDNF) from alginate thin film coatings on silicon electrodes was evaluated.Electrode coatings were manufactured via spinner coating using 0.45 μm filtered 2% (w/v) or 4% (w/v) alginate solutions on silicon wafer substrates. To crosslink the alginate two different methods of crosslinking were evaluated, the fast CaCl2 crosslinking and the slow CaCO3-GDL crosslinking method. However CaCl2 crosslinking using an aerosolized spray produced consistent alginate coatings compared to the CaCO3-GDL crosslinking method and was subsequently used for all experiments. Thickness measurements using the profilometer showed that CaCl2 crosslinked alginate coatings in the micron level can be produced by spin coating 0.45 μm filtered, 4% alginate solutions at 1000 rpm for 30-60 seconds. When multiple layers of alginate were applied on top of one another, coatings of thicknesses ranging from 5 μm to 80 μm were produced via spinner coating. To simulate BDNF release, all alginate films were loaded with either model proteins (lysozyme or chymotrypsinogen) or poloxamer (p-188), a polymer that has been shown to have membrane-sealing properties. In-vitro release studies from all loaded films were conducted in PBS (pH 7.4) at 37°C until all protein or poloxamer was released. Results from the release studies showed rapid release profiles for both model proteins and p-188. Complete release of proteins and p-188 took place within the first three hours. This is well short of the anticipated 3-4 day release period required for BDNF. In order to prolong release for BDNF, the effect of addition of a poly-L-ornithine (PLO) coating on the alginate layer was evaluated. PLO coatings at three different concentrations, 0.1(w/v) %, 0.5% and 1% were applied on the surface of alginate films. Subsequent release studies showed very similar release profiles between the PLO-coated and the uncoated films, and were probably due to the detachment of the film from the silicon surface early in the release.The results of this study clearly show the feasibility of manufacturing neurotrophin releasing alginate coatings for silicon electrodes. The versatile coating method can be used to deliver a number of different compounds including proteins like neurotrophins and polymers like p-188. However to achieve controlled release over longer periods of 3-4 days, alternate coating methods will need to be investigated.M.S., Biomedical Engineering -- Drexel University, 200
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
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
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