1,720,976 research outputs found
Self-assembled nanoparticles as new smart contrast agents for magnetic resonance imaging
Get PDFDissertação de mest., Ciências Biomédicas, Faculdade de Ciências e Tecnologia, Univ. do Algarve, 2010The aim of this thesis is to develop smart and targeted nanoparticle contrast agents for Magnetic Resonance Imaging. These nanoparticles were designed to improve the sensitivity of this high resolution imaging technique and thereby improve early cancer detection, which is a major factor for the reduction of cancer mortality. The designed nanoparticles are expected to accumulate in the tumor through passive and active targeting. In addition, when exposed to the characteristic low pH of the cancer microenvironment, the nanoparticles will release the contrast agent, which will turn on its imaging capability. This contrast agent consists of pH-sensitive polymeric micelles formed by self-assembly, loaded with Gadolinium (III) complexes and bioconjugated with the C595 monoclonal antibody against the human MUC1 protein, which is overexpressed during tumorigenesis since its early stages.
The capability of micelles to disintegrate and release the encapsulated contrast in acidic conditions was proved by 1.5T MRI experiments. The MRI study showed no image signal from the sample with intact micelles whereas a signal enhancement was observed from the sample at low pH. After one mouse has been intramuscularly injected with Gadolinium(III)-loaded micelles in both hind legs, the MR image demonstrated a stronger signal from the right hind leg, which was previously injected with an acid solution. To assess in vitro cytotoxicity of free and encapsulated Gadolinium (III) complexes in polymeric micelles, MTT assays were performed on different cancer cell lines. Encapsulated Gadolinium (III) complexes showed significantly lower cytotoxicity than free Gadolinium (III) complexes, even at the highest concentration. To verify the target capability of nanoparticles, fluorescent dye-loaded polymeric micelles were incubated with breast cancer cells expressing MUC1 (verified by semi-quantitative RT-PCR, Western blotting and flow cytometry) and mouse bone marrow stroma cells. Antibody-conjugated micelles had superior affinity for MUC1-expressing human breast cancer cells than for mouse bone marrow cells
Utilisation du groupement benzyloxycarbonyle en tant que groupement protecteur en chimie des sucres
No full textMONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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