1,720,957 research outputs found
Helicity‐Dependent Enzymatic Peptide Cyclization
No full textThe secondary structure plays a crucial role in the biological activity of peptides. Various strategies have been developed to stabilize particular peptide conformations, including sequence modifications and macrocyclization approaches. Often, the interplay between conformational constraint and flexibility is central to bioactivity. Here, we investigate how peptide α-helicity influences enzymatic head-to-tail cyclization using an engineered Sortase. We show that peptides with low helicity readily undergo intramolecular cyclization, while more rigid, helical peptides exhibit complex cyclization behaviors including cyclic dimer formation. These findings reveal that increased peptide rigidity can redirect enzymatic reactions from intramolecular to intermolecular processes, and demonstrates how changes in molecular rigidity can guide chemical reactivity. These insights can advance the design of peptide-derived materials, hydrogels, and stimuli-responsive probes
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
Modulating Protein-Protein Interactions via Peptide-Based Inhibitors: Structural and Functional Insights
Full text linkAs potential therapeutic targets, protein-protein interactions (PPI) are primary to cellular function and processes. This thesis explores peptide-based PPI inhibitors with respect to their design, structural characterization, and functional analysis. The main focus is the modulation of peptide-based PPI inhibitors through conformational stabilization and binding affinity optimization. Chapter 1 (Introduction) provides an overview of protein structure principles, highlighting the importance and role of PPI in biological processes. It introduces the challenges related to targeting these interactions and the ability of peptides and peptidomimetics as promising PPI modulation tools. Furthermore, background information of structural biology techniques such as X-ray crystallography, and biophysical methods is provided. Chapter 2 (Peptide-Based Covalent Inhibitors of Protein-Protein Interactions) reviews strategies to stabilize protein structures and the progression from peptides to peptidomimetics. One of the key focuses is the importance of structure stabilization to design functional biomimetics. It also covers how stabilization of protein structures can increase their usefulness in biotechnological applications. Chapter 3 (Fragment Screening of NF-YB/C Heterodimer: Towards Novel Inhibitors of NF-Y Activity) investigates the identification of potential small-molecule inhibitors of the NF-Y trimer formation using fragment-based drug design approach. An attempt was made to optimize crystallization system for successful fragment screening, thus crystallization optimizations were carried out, nonetheless no fragment hits were acquired. Hence, this chapter also discusses the difficulties in targeting NF-Y with fragment-based discovery, and shares insights that might be useful for alternative screening and inhibitor design strategies. Chapter 4 (Binding Dynamics of a Stapled Peptide Targeting the Transcription Factor NF-Y) researches the design, synthesis, and characterization of different stapled peptides as NF-Y inhibitors. Hydrocarbon peptide stapling improves peptide helicities and interaction of the peptides with the protein target. Moreover, this chapter identifies the minimal binding core in a 13-mer stapled peptide and discovers the flexibility of its structure when bound to NF-YB/C heterodimer. Chapter 5 (Helicity-Dependent Enzymatic Peptide Cyclization) describes how peptide α-helicity influences enzymatic head-to-tail peptide cyclization using engineered Sortase. Results show that peptides with low helicity allow efficient cyclization, while more rigid helical peptides incline towards complex cyclization by forming cyclic dimers or oligomers. This chapter also features how fine-tuning secondary structures can influence the chemical reaction through modulating the relationship between peptide rigidity and enzymatic cyclization
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
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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