1,720,980 research outputs found
Synthesis and Structural Characterizations of New Coordination Polymers Generated by the Interaction Between the Trinuclear Triangular SBU [Cu 3 (μ 3 -OH)(μ-pz) 3 ] 2+ and 4,4′-Bipyridine. 3°
No full textThe reactions of 4,4′-bipyridine with selected trinuclear triangular copper(II) complexes, [Cu3(μ3-OH)(μ-pz)3(RCOO)2Lx], [pz = pyrazolate anion, R = CH3(CH2)n (2 ≤ n ≤ 5); L = H2O, MeOH, EtOH] yielded a series of 1D coordination polymers (CPs) based on the repetition of [Cu3(μ3-OH)(μ-pz)3] secondary building units joined by bipyridine. The CPs were characterized by conventional analytical methods (elemental analyses, ESI-MS, IR spectra) and single crystal XRD determinations. An unprecedented 1D CP, generated through the bipyridine bridging hexanuclear copper clusters moieties, two 1D CPs presenting structural analogies, and two monodimensional tapes having almost exactly superimposable structures, were obtained. In one case, the crystal packing makes evident the presence of small, not-connected pores, accounting for ca. 6% of free cell volume
Synthesis and Characterization of New Ruthenium(II) Arene Acylpyrazolone Complexes
No full textArene ruthenium(II) complexes have been widely studied in the recent years, and their chemistry has been extensively studied for arenes such as benzene and para-cymene. They have found applications in catalysis, supramolecular assemblies, molecular devices.1 Moreover, they have shown antiviral, antibiotic and anticancer activities.2 Recently, mononuclear Ru-acylpyrazolone complexes have been shown to exhibit interesting in vitro activity in some cancer cells.3 On the basis of the our previous work,4 we extend our investigation to the interaction of several acylpyrazolones ligands with (arene)ruthenium(II)dichloride acceptors and PTA (1,3,5-triaza-7-phosphaadamantane)(Figure 1). Their structures have been confirmed by analytical and spectral data. X-ray diffraction studies and their biological activity are under investigation
Bioactivity of Curcuminoids in Half-Sandwich Ru(II), Rh(III) and Ir(III) Complexes: benefits from cooking to medicine
No full textCurcumin has been used for centuries in Asia as a spice, natural colouring and traditional medicine owing to its anti-inflammatory, antioxidant and antitumoral effects [1]. An alternative strategy to improve the properties of curcumin, without the need to modify the drug, is its incorporation into metal complexes [2]. Ruthenium compounds have emerged in recent years as promising alternatives to
platinum drugs by displaying specific activities against different cancers, favorable toxicity and clearance properties [3]. Recently, also metal complexes based on Rhodium and Iridium have arisen as fascinating potential alternative metallodrugs [4]. In the present work we exploit the coordination chemistry of Ru(II) arene and pentamethylcyclopentadienyl Rh(III) and Ir(III) complexes with curcumin [5] and bisdemethoxycurcumin as co-ligands and full characterization of relative RAPTA type complexes with 1,3,5-triaza-7-phosphaadamantane ligand (PTA) [6]. Hydrolysis studies were carried out under pseudopharmacological conditions to evaluate their aqueous chemistry. The antiproliferative effects in two human ovarian cancer cell lines (A2780 and A2780cisR) and non-tumorigenic human embryonic kidney cells (HEK293) will be reported
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
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