1,720,959 research outputs found
Lysine residues at the first and second KTKEGV repeats mediate α-Synuclein binding to membrane phospholipids
No full textWhile α-Synuclein (α-Syn) is mainly detected as a cytosolic protein, a portion of it is recovered bound to membranes. It is suggested that binding to membrane phospholipids controls α-Syn structure, physiology and pathogenesis. We aimed at investigating the role, of the positive charged lysine residues at the KTKEGV repeat motif, in mediating α-Syn associations with membrane phospholipids and in α-Syn oligomerization and aggregation. Specifically, two positive lysine (K) residues were replaced with two negative glutamic acid (E) residues at either the first or second KTKEGV repeat motifs. The effect of these mutations on membrane binding was determined by a quantitative phospholipid ELISA assay and compared to wild-type α-Syn and to the Parkinson's disease-causing mutations, A30P, E46K and A53T. We found that the K to E substitutions affected α-Syn binding to phospholipids. In addition, K to E substitutions resulted in a dramatically lower level of soluble α-Syn oligomers and larger intracellular inclusions. Together, our results suggest a critical role for lysine residues at the N-terminal repeat domain in the pathophysiology of α-Syn
System interdiction and defense
Get PDFWe study the problem of interdicting components of an adversary's system, e.g., a war-time economy, a transportation network, etc. Basic techniques are developed and illustrated with a simple network interdiction problem, "maximizing the shortest path" (MXSP). In MXSP, an interdictor wishes to employ limited interdiction resources as effectively as possible to slow an adversary in moving between two network nodes. "Interdiction" destroys a network arc entirely or increases its effective length through an attack. This bi-level, max-mm problem is formulated as a mixed-integer program (MIP), but unique decomposition algorithms are developed to solve the problem more efficiently than standard branch and bound. One algorithm is essentially Benders decomposition with special integrality cuts for the master problem. A second algorithm uses a new set-covering master problem, and a third is a hybrid of the first two. We extend our techniques (i) to solve general system-interdiction problems, some of which cannot be formulated as is, (ii) to solve system-defense problems where critical system components must be identified and hardened against interdiction, and (iii) to solve interdiction problems with uncertain interdiction success. We report computational experience for MXSP, a shortest- path network-defense problem and MXSP with uncertain interdiction successApproved for public release; distribution is unlimited.Major, Israeli Air-Forcehttp://archive.org/details/systeminterdicti10945905
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
- …
