1,720,956 research outputs found
Study of protein denaturation and protein-ligand interaction using high pressure methods.
No full textThe purpose of this thesis is to develop methods that allow to determine the volumes of protein-ligand interactions, which is an important but rarely researched thermodynamic characteristic. Determination of binding volume could be used in the development of anticancer drugs, targets of which could be proteins used in this research for example Human Chaperon Protein 90 (HSP90) or Carbonic anhydrases. In this thesis protein-ligand interaction was researched using high pressure fluorimetry, changes in the fluorescence spectra of carbonic anhydrases that appear during conformation change in high pressure were analyzed. Melting pressures of I, II and XIII carbonic anhydrase isoforms and their relation to denaturant concentration were determined. By changing the concentrations of ligand and denaturant the binding volume of acetazoleamide to carbonic anhydrase II was determined. Also nuclear magnetic resonanse was used to research HSP90N-terminal domain conformation changes and ligand binding in high pressure. Using this method amino acids, that are first to change their environment during pressure denaturation, were identified. Also amino acids that are important in ligand binding were identified. By conducting experiments in high pressure using varying ligand concentrations the binding volume of an inhibitor ICPD9 was calculated
Termodinaminiai parametrai baltymų-ligandų modelinėse sistemose: jungimosi tūrio ir sąveikos energijos tyrimas.
No full textUnderstanding protein-ligand binding thermodynamic parameters is fundamental for rational drug design. However, despite the importance, due to the complexity of protein-ligand systems, areas of this field, including volume change due to protein-ligand binding (Vb) and ionic interaction, are left largely unexplored. This thesis researches the volumetric characteristics of protein-ligand binding in carbonic anhydrase (CA)-sulfonamide model systems. CA XIII unfolding pathway using guanidinium hydrochloride (GdmHCl) was determined for the first time. The relationship between melting pressure (Pm) and GdmHCl concentration was evaluated for CA I, CA II, and CA XIII. A concept of fluorescent pressure shift assay technique using different GdmHCl and ligand concentrations for strong ligand Vb determination was proposed. The high-pressure NMR technique was employed to determine Vb values of primary sulfonamide inhibitor binding to CA I and CA II. A method for determining changes in volume upon protein-ligand binding from a single series of NMR spectra was described for the first time.A model system consisting of oppositely charged amino acid homopolymers and surfactants was used to determine the contributions of chemical modifications and ionic interaction toward protein-ligand binding. Contributions of alkyl chain and head group make-up towards enthalpy and heat capacity of interactions were determined for the first time in an oppositely charged poly(amino acid)- surfactant system
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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