1,721,135 research outputs found
Horst Enzensberger. — Beiträge zum Kanzlei- und Urkundenwesen der normannischen Herrscher Unteritaliens und Siziliens
No full textLabande Edmond René, Pratesi Alessandro. Horst Enzensberger. — Beiträge zum Kanzlei- und Urkundenwesen der normannischen Herrscher Unteritaliens und Siziliens. In: Cahiers de civilisation médiévale, 16e année (n°63), Juillet-septembre 1973. pp. 248-251
Limiti e difficoltà dell'uso dell'informatica per lo studio della forma diplomatica e giuridica dei documenti medievali
No full textPratesi Alessandro. Limiti e difficoltà dell'uso dell'informatica per lo studio della forma diplomatica e giuridica dei documenti medievali. In: Informatique et histoire médiévale. Actes du colloque de Rome (20-22 mai 1975) Présentés par Lucie Fossier - André Vauchez - Cinzio Violante. Rome : École Française de Rome, 1977. pp. 187-190. (Publications de l'École française de Rome, 31
Reevaluating the Mechanistic Insights of α-TOS-Bearing Pt(IV) Anticancer Complexes: A New Perspective from a More In-Depth Knowledge
No full textPt(IV) prodrugs have been extensively studied over the years with the aim of overcoming the limitations of traditional Pt(II) drugs. In this frame, two cisplatin-based Pt(IV) complexes bearing α-tocopherol succinate (α-TOS, a derivative of vitamin E) in the axial position (namely, [PtCl2(NH3)2(OEt)(α-TOS)] and [PtCl2(NH3)2(α-TOS)2] were reported in recent years and their cytotoxicity was evaluated. In particular, [PtCl2(NH3)2(OEt)(α-TOS)] was reported to be more cytotoxic than [PtCl2(NH3)2(α-TOS)2]. In the present comment paper, reasons for the different cytotoxicity of these complexes are discussed in detail and, more in general, a comprehensive elucidation of the mechanism of action of this class of anticancer Pt(IV) compounds is provided. Hopefully, these findings and the resulting improved knowledge of these drugs will help researchers design new and improved Pt(IV) anticancer drugs
Exploiting the Chemical Diversity of Metal Compounds as a Source of Novel Anti-COVID-19 Drugs
Full text linkThe outbreak of the COVID-19 pandemic has triggered the strong and urgent need of finding new effective drugs against the SARS-CoV-2 virus. Despite the intense efforts made by the international scientific community in the course of the last two years and some initial success, this issue remains absolutely open. Metal-based agents form a class of substances possessing a large variety of chemical structures and reactivities that may result in innovative and unprecedented modes of action. This class of substances merits to be explored in the search of effective antiviral agents. In this short review, we offer some examples of the possible role of metal-based drugs as prospective anti-COVID-19 agents. Particular attention is paid to a few established gold and bismuth compounds that looked very promising in some preliminary tests of antiviral efficacy. In addition, we illustrate a systematic strategy proposed very recently by Ott et al. for the rational discovery of promising antiviral drug candidates within relatively large libraries of metal compounds. Notably, implementation of this strategy has already resulted in the identification of a few metal compounds endowed with interesting features suitable for further pharmacologic development. Overall, we aim to underscore the valuable role that medicinal inorganic chemistry may play in the search and discovery of new anti-COVID-19 drugs
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
Impact of ring size on the copper(II) coordination abilities of cyclic tetrapeptides
No full textA new, 14-membered, tetraza cyclic tetrapeptide containing histidine and lysine side-chains, c(b3homo- LysdHisb-AlaHis), was designed, synthesized and characterized; its copper(II) binding properties were investigated in dependence of pH by potentiometric and spectroscopic methods. In line with previous studies of similar systems, the progressive involvement of amide nitrogens in copper(II) coordination was evidenced for pH values greater than 6. At physiological pH the dominant species consists of a cop- per(II) center coordinated by two amide nitrogens, an imidazole nitrogen and a water molecule. In con- trast, at pH values higher than 8.7, a copper(II) coordination environment consisting of four amide nitrogens in the equatorial plane and the axial imidazole ligands is formed as clearly indicated by spec- troscopic data and theoretical calculations. The behavior of this 14-membered cyclic tetrapeptide is com- pared to that of its 12-membered cyclic analog, particular attention being paid to the effects of ring size on the respective copper(II) binding abilities
Pd(II)/1,10-phenanthroline complexes bearing arene ligands: On the role of N- vs O-coordination to tune their cellular activity and binding ability towards DNA and RNA
No full textThree Pd(II)-based complexes of 1,10-phenanthroline and N- or O-coordinating ligands have been synthesised and tested with different relevant biosubstrates like double-stranded DNA, double and triple helix of RNA, DNA G-quadruplexes of different conformations and bovine serum albumin. Here a correlation between N- vs O-coordinating elements and binding mechanism emerged, where the N-coordinating ligands proved to be the most promising. These outcomes were confirmed also in the cellular experiments. The Pd(II) complex with naphthalene-1,8-diamine is the one that is able to be carried by BSA, to strongly bind nucleic acids, to produce reactive oxygen species (ROS) and to show the best cellular performances (poorly toxic towards healthy cells and highly toxic against the cisplatin-resistant cancer cell line). On the opposite, the complex with benzene-1,2-diolate may be sequestered by BSA, weakly binds nucleic acids, does not produce ROS and shows poor cellular activity. The complex with benzene-1,2-diamine stays in between. Other mechanistic details are discussed which show that the biophysical behaviour is the sum of the contribution of aromaticity, charge and N- or O-coordination
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