1,720,960 research outputs found
Functional cavitands as artificial enzymes: bridging computational and synthetic strategies for supramolecular catalysis and beyond
No full textENG- To address the limitations hindering the broader adoption of functional and expanded cavitands, this thesis combines computational studies, synthetic refinement, and novel application-driven design strategies. A central focus was placed on understanding cavitand flexibility and host-guest interactions through Molecular Dynamics simulations, which offered a deeper view of their behavior in solution and enabled the prediction of guest affinities—especially valuable for a new family of highly flexible calix[5]arene-based systems. Concurrently, synthetic strategies were revisited to enhance accessibility and functional diversity. Key intermediates in traditional routes were optimized to facilitate access and improve yields towards functional cavitands, while a more practical and safer pathway was developed for acridane[4]arene-derived expanded cavitands. Building on these advances, the catalytic potential of cavitands was explored through terpene cyclizations, demonstrating that even a simple functional receptor could promote selective transformations, favoring terpene formation despite its thermodynamic disadvantage. Finally, the lessons gathered throughout this work informed the development of a rational design strategy, integrating enzymatic inspiration with computational and synthetic tools. This new tool was exemplified with the design of de novo thiourea-bearing cavitands tailored for bioinspired catalysis.
Together, these contributions help unlock the untapped potential of cavitands as versatile platforms in supramolecular chemistry and bioinspired catalysis, demonstrating that well-designed synthetic systems will soon begin to rival the precision and elegance of natural enzymesCAT- Per superar les limitacions que amenacen l’àmplia adopció dels cavitands funcionals i expandits, aquesta tesi combina estudis computacionals, refinament sintètic i noves estratègies de disseny orientades a l’aplicabilitat. Es va posar un èmfasi especial en entendre la flexibilitat dels cavitands i les interaccions host-guest mitjançant simulacions de Dinàmica Molecular, les quals van aportar una visió profunda del seu comportament en solució i van permetre predir l’afinitat per diversos guests—una eina especialment útil en una nova família de cavitands altament flexibles basats en calix[5]arens. Paral·lelament, es van examinar les estratègies sintètiques per millorar-ne l’accessibilitat i la diversitat funcional. Es van optimitzar intermediaris clau en les rutes tradicionals per facilitar l’accés a cavitands funcionals i augmentar-ne el rendiment, i també es va establir una ruta més pràctica i segura pels cavitands expandits derivats d’acridane[4]arè. A partir d’aquests avenços, es va explorar el potencial catalític dels cavitands a través de ciclitzacions de terpens, demostrant que un receptor funcional senzill podia promoure transformacions selectives, afavorint la formació de llimonè tot i el seu desavantatge termodinàmic. Finalment, les lliçons extretes d’aquest treball van servir per desenvolupar una estratègia de disseny racional que integra inspiració enzimàtica amb eines computacionals i sintètiques, exemplificant aquesta nova eina amb cavitands funcionalitzats amb grups tiourea per a catàlisi bioinspirada.
En conjunt, aquestes aportacions contribueixen a desbloquejar el potencial encara no completament explotat dels cavitands com a plataformes versàtils en química supramolecular i catàlisi bioinspirada, demostrant que els sistemes sintètics ben dissenyats ben aviat podran arribar a rivalitzar la precisió i l’elegància dels enzims naturalsPrograma de Doctorat en Químic
Functional cavitands as artificial enzymes: bridging computational and synthetic strategies for supramolecular catalysis and beyond
No full textENG- To address the limitations hindering the broader adoption of functional and expanded cavitands, this thesis combines computational studies, synthetic refinement, and novel application-driven design strategies. A central focus was placed on understanding cavitand flexibility and host-guest interactions through Molecular Dynamics simulations, which offered a deeper view of their behavior in solution and enabled the prediction of guest affinities—especially valuable for a new family of highly flexible calix[5]arene-based systems. Concurrently, synthetic strategies were revisited to enhance accessibility and functional diversity. Key intermediates in traditional routes were optimized to facilitate access and improve yields towards functional cavitands, while a more practical and safer pathway was developed for acridane[4]arene-derived expanded cavitands. Building on these advances, the catalytic potential of cavitands was explored through terpene cyclizations, demonstrating that even a simple functional receptor could promote selective transformations, favoring terpene formation despite its thermodynamic disadvantage. Finally, the lessons gathered throughout this work informed the development of a rational design strategy, integrating enzymatic inspiration with computational and synthetic tools. This new tool was exemplified with the design of de novo thiourea-bearing cavitands tailored for bioinspired catalysis.
Together, these contributions help unlock the untapped potential of cavitands as versatile platforms in supramolecular chemistry and bioinspired catalysis, demonstrating that well-designed synthetic systems will soon begin to rival the precision and elegance of natural enzymesCAT- Per superar les limitacions que amenacen l’àmplia adopció dels cavitands funcionals i expandits, aquesta tesi combina estudis computacionals, refinament sintètic i noves estratègies de disseny orientades a l’aplicabilitat. Es va posar un èmfasi especial en entendre la flexibilitat dels cavitands i les interaccions host-guest mitjançant simulacions de Dinàmica Molecular, les quals van aportar una visió profunda del seu comportament en solució i van permetre predir l’afinitat per diversos guests—una eina especialment útil en una nova família de cavitands altament flexibles basats en calix[5]arens. Paral·lelament, es van examinar les estratègies sintètiques per millorar-ne l’accessibilitat i la diversitat funcional. Es van optimitzar intermediaris clau en les rutes tradicionals per facilitar l’accés a cavitands funcionals i augmentar-ne el rendiment, i també es va establir una ruta més pràctica i segura pels cavitands expandits derivats d’acridane[4]arè. A partir d’aquests avenços, es va explorar el potencial catalític dels cavitands a través de ciclitzacions de terpens, demostrant que un receptor funcional senzill podia promoure transformacions selectives, afavorint la formació de llimonè tot i el seu desavantatge termodinàmic. Finalment, les lliçons extretes d’aquest treball van servir per desenvolupar una estratègia de disseny racional que integra inspiració enzimàtica amb eines computacionals i sintètiques, exemplificant aquesta nova eina amb cavitands funcionalitzats amb grups tiourea per a catàlisi bioinspirada.
En conjunt, aquestes aportacions contribueixen a desbloquejar el potencial encara no completament explotat dels cavitands com a plataformes versàtils en química supramolecular i catàlisi bioinspirada, demostrant que els sistemes sintètics ben dissenyats ben aviat podran arribar a rivalitzar la precisió i l’elegància dels enzims naturalsPrograma de Doctorat en Químic
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
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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