1,721,086 research outputs found
Interacção biomembranar : parâmetros que influenciam a ligação de dendrimeros, peptidos lipidados e carregados electricamente a biomembranas
No full textDissertação de mestrado em Biofísica em BionanossistemasTodas as células, unidade de vida, apresentam-se compartimentalizadas por uma
bicamada lipídica permitindo que numerosos processos ocorram á superfície dos
organelos por uma associação reversível de proteínas do citosol. Nestes processos simples
parâmetros físicos como, curvatura membranar e/ou densidade de carga poderão ser
importantes “inputs” para criar respostas temporais e espaciais.(Bigay & Antonny, 2012).
A maioria dos estudos encontram-se focados em parâmetros físico-quimicos das
biomoléculas como os maiores reguladores na interacção com membranas. Deste modo o
papel desempenhado pelas propriedades membranares não se encontram completamente
elucidados.
Neste projecto, eu irei investigar a um nível singular as propriedades físicas das
biomembranas e a sua directa influência na associação reversível com biomoléculas. Para
este efeito, eu irei utilizar biomoléculas com função definida e analisar o seu
comportamento quando importantes parâmetros associados as mesmas são manipulados.
De modo a obter estes objectivos, irei utilizar um ensaio “in-vitro”, onde lipossomas
fluorescentes individuais serão imobilizados numa superfície de vidro e visualizados
usando microscopia laser confocal.
Deste modo, eu planeei o uso de lipossomas singulares e monitorizar como os parâmetros
membranares afectam a ligação de três classes diferentes de moléculas: primeiramente um
péptido lipidado derivado da GTPase N-Ras (tN-Ras), para o estudo da forma da
membrana na ligação peptídica. Em segundo o dendrimero (PAMAM G6) para elucidar o
papel desempenhado pelas interacções hidrofóbicas e electroestáticas. Por último um
péptido derivado da proteína membranar myristoyled alanine-rich C kinase substrate
(MARCKS), para o estudo de como o pH de lipossomas individuais poderão regular o
recrutamento específico de péptidos altamente catiónicos.All cells, the unit of life, are compartmentalized by a lipid bilayer allowing numerous
molecular processes to occur at the surface of organelles through reversible association of
proteins from the cytosol. In these processes simple physical parameters such as
membrane curvature and/or charge density can be important inputs to create sharp
temporal and spatial responses.(Bigay & Antonny, 2012)
Most studies focus on the physicochemical parameters of the biomolecules as the major
regulators of the interaction with membranes. This means that the role played by
membrane properties are still not fully understood.
In this project, I will investigate at single level the physical properties of biomembranes
and their direct influence in the reversible association with biomolecules. For this, I will
be using biomolecules with defined function to analyze the behavior when important
parameters associated with biomembranes are manipulated. To accomplish these goals, I
will use an in vitro assay, where individual fluorescent liposomes are immobilized on a
glass surface and imaged using confocal microscopy.
Thus, I planned use of single liposomes and monitor parameters affecting the membrane
binding of three different classes of molecules: first lipidated peptide derived from the NGTPase
RAS (tN-RAS) for the study of the membrane shape in the peptide bond.
Secondly, a dendrimer (PAMAM G6), to elucidate the role of hydrophobic and
electrostatic interactions. Finally, a peptide derived from the membrane protein
myristoyled alanine-rich C kinase substrate (MARCKS), to study how the individual pH
of liposomes may regulate the recruitment of specific highly cationic peptide
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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