125,526 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Sabba da Castiglione collezionista di antichità
No full textSabba da Castiglione (Milano 1480 – Faenza 1554) soggiornò a lungo nell’Oriente greco in gioventù, all’epoca della sua militanza nell’ordine dei cavalieri di S. Giovanni. Da Rodi, dove prestava il suo servizio, effettuò diversi viaggi nel Mare Egeo e visitò numerose isole, allo scopo di cercare manufatti antichi da inviare a Isabella d’Este, che lo aveva incaricato di procurarle nuovi pezzi per la sua collezione mantovana. Lo stesso Sabba ebbe modo di crearsi una propria raccolta, della quale nel presente lavoro si discutono intenti e peculiarità
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
Imidazo[2,1-b] Thiazole: Introduction, Current and Perspective
No full textImidazo[2,1-b]thiazole is a fused heterobicyclic system containing bridgehead
nitrogen atom. Derivatives of this scaffold are especially attractive in the field of
medicinal chemistry because of their broad spectrum of biological activities. The
imidazo[2,1-b]thiazole system constitutes the core unit of the well-known
anthelminthic and immunomodulatory agent Levamisole, marketed
under the trade name Ergamisol© and discovered at Janssen Pharmaceutica in 1966
On the reactivity of nitrosoimidazoles with acids (the Cusmano-Ruccia reaction): a continuous source of new ring- into-ring interconversion
No full textAn extension of the ‘Cusmano–Ruccia’ reaction is reported. 6-(4-chlorophenyl)-3-methyl-5-nitrosoimi-dazo[2,1-b]oxazole by the action of hydrochloric acid gives 3-(4-chlorobenzoyl)-5-methyl-1,2,4-oxadiaz-ole (13); presumably via ammonium ion, CO2 and methanol elimination. The relevance of the nature of the atom of the B-ring linked to C-2 of the imidazole for the occurrence of the ring-into-ring interconver-sion has been once more confirmed
Diethyl 4-(6-Chloroimidazo[2,1-b]thiazol-5-yl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate and Ethyl 4-(6-Chloroimidazo[2,1-b]thiazol-5-yl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate
No full textDiethyl 4-(6-chloroimidazo[2,1-b]thiazol-5-yl)-2,6-dimethyl-1,4-dihydropyridine- 3,5-dicarboxylate and ethyl 4-(6-chloroimidazo[2,1-b]thiazol-5-yl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate were obtained simultaneously by the Biginelli reaction using a green protocol and curtailing reaction time
Now casting of traffic state by GPS data. The metropolitan area of Rome
No full textIn the near future a large amount of data on individual vehicle position and speed for the full road network will be available from GPS systems. This possibility opens new research perspectives for prevention and governance of congestion and of traffic criticalities. A prototype model, developed under Pegasus Project sponsored by the Italian Ministry of Industry, is working in Rome. The system is based on the real time reconstruction of the speed, density and flux on the whole metropolitan road network using a low sampling rate GPS data set. We present the state of the art of the project discussing its strength and weakness. We then show the results of the data analysis for the month of May 2010
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