1,720,969 research outputs found
Mesoporous nanocrystalline TiO2 loaded with ferulic acid for sunscreen and photo-protection: safety and efficacy assessment
No full textIn the present study, the use of surfactant-free mesoporous TiO2 combined with an antioxidant and photoprotecting agent, such as ferulic acid (FA), as a sunscreen was investigated for the first time. Ferulic acid is a natural antioxidant characterized by UV absorption capacity and radical scavenging activities and, due to these properties, it has been approved as an active ingredient in several skin lotions and sunscreens. However, despite the double function exerted by FA, the use of this molecule in the cosmetic field is limited by its poor stability. Aiming to overcome this drawback, mesoporous TiO2, prepared by using a sol-gel route assisted by a polyoxyethylene-polyoxypropylene block copolymer template followed by solvothermal treatment, was used as a matrix for the encapsulation of ferulic acid. The stability studies performed confirmed the ability of the prepared material to preserve the active molecule from degradation induced by light and, therefore, its properties. Antioxidant and anti-inflammatory activities of FA-loaded titania (TiO2@FA) and titania matrix (TiO2) were evaluated and high scavenging activity towards DPPH, ABTS and NO radicals were recorded. The in vitro assessment of the spectrophotometric Sun Protection Factor (SPF) was also performed and a value of 14.7 was observed for TiO2@FA while mesoporous TiO2 showed a lower SPF value equal to 2.6. These results suggested the potential application of the titania-doped FA as a "booster of SPF" that is able to enhance the SPF of a sunscreen. Furthermore, in vitro safety studies confirmed the biocompatibility of the prepared material and the absence of skin irritation
Smart Bandage Based on Molecularly Imprinted Polymers (MIPs) for Diclofenac Controlled Release
Full text linkThe aim of the present study was the development of a “smart bandage” for the topical administration of diclofenac, in the treatment of localized painful and inflammatory conditions, incorporating Molecularly Imprinted Polymers (MIPs) for the controlled release of this
anti-inflammatory drug. For this purpose, MIP spherical particles were synthesized by precipitation polymerization, loaded with the therapeutic agent and incorporated into the bandage surface. Batch adsorption binding studies were performed to investigate the adsorption isotherms and kinetics and the selective recognition abilities of the synthesized MIP. In vitro diffusion studies were also carried out using Franz cells and the obtained results were reported as percentage of the diffused dose, cumulative amount of diffused drug, steady-state drug flux and permeability coefficient. Moreover, the biocompatibility of the developed device was evaluated using the EPISKINTM model.
The Scatchard analysis indicated that the prepared MIP is characterized by the presence of specific binding sites for diclofenac, which are not present in the corresponding non-imprinted polymer, and the obtained results confirmed both the ability of the prepared bandage to prolong the drug release and the absence of skin irritation reactions. Therefore, these results support the potential application
of the developed “smart bandage” as topical device for diclofenac sustained release
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
Biopolymeric self-assembled nanoparticles for enhanced antibacterial activity of Ag-based compounds
No full textMicrobial infections are still one of the major causes of death among world population. For
this reason, there is an urgent need of new antimicrobial agents that express antibacterial activity.
Silver-based compounds are known to be toxic against bacteria. One of the most representative
examples is silver sulfadiazine. In our article we report the antibacterial activity of silver Nheterocyclic
carbene complexes, tested againt a wide spectrum of microorganisms. MIC and MBC
were calculated for each compound.
We have also produced a dextran oleate conjugate, that was employed for the preparation of
self-assembled biopolymeric nanoparticles
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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