1,721,156 research outputs found
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
Guida all’escursione: Geologia e geomorfologia del settore fermano nel bacino periadriatico marchigiano-abruzzese.
No full textHere we have a brief description of geology and geomorphology character of Plio-pleistocene lands of Ascoli Province (AP) and relative summary of third day field trip of the 3 rd Geology and Information Technologies Group Congress, held in Offida, Italy, from 3 rd to 5 th of June 2008. We describe Neogene-Pleistocenic periadriatic sector evolution, sequence of events and geomorphologic character of Southern-central Marche highlands
Simultaneous detection of the exon 10 polymorphism and a novel intronic single base insertion polymorphism in the XPD gene using single strand conformation polymorphism
No full textWe developed a new method based on the single strand conformation polymorphism (SSCP) technique for the detection of a G23591A (Asp312Asn) polymorphism in exon 10 of the XPD gene. In the process we also identified a novel polymorphism 23623C-ins (IVS10 + 17C-ins) in intron 10 of the same gene. With this newly developed SSCP-based method of genotyping we could detect both polymorphisms in the same assay and thus consequently determine the haplotype. In order to determine the population frequency of the novel polymorphism and the haplotype frequency, 302 healthy individuals were genotyped. The allelic frequency of the 23623C-ins intronic polymorphism was 0.16, whereas the frequency of the variant allele for the G23591A polymorphism was 0.39. Forty-three individuals (14%) were heterozygous for both polymorphisms but none carried polymorphic variants for both G23591A and 23623C-ins on the same allele. The effect of the novel intronic insertion polymorphism, which is located 16 nt downstream of the 3′-end of exon 10 of the XPD gene and involves a mononucleotide C repeat sequence, on expression remains to be determined
Activating BRAF and N-Ras mutations in sporadic primary melanomas: An inverse association with allelic loss on chromosome 9
No full textWe searched and report mutations in the BRAF and N-ras genes in 22 out of 35 (63 percent) primary sporadic melanomas. In three melanomas, mutations were concomitantly present in both genes. In all, 10 out of 12 mutations in the BRAF gene involved the 'hot spot' codon 600 (In all communications on mutations in the BRAF gene, the nucleotide and codon numbers have been based on the NCBI gene bank nucleotide sequence NM_004333. However, according to NCBI gene bank sequence with accession number NT_007914, there is a discrepancy of one codon (three nucleotides) in exon 1 in the sequence with accession number NM_004333. The sequence analysis of exon 1 of the BRAF gene in our laboratory has shown that the sequence derived from NT_007914 is correct (Kumar et al., 2003). Due to the correctness of the latter, sequence numbering of codons and nucleotides after exon 1 are changed by +1 and +3, respectively.), one tandem CT1789-90TC base change represented a novel mutation and another mutation caused a G466R amino-acid change within the glycine-rich loop in the kinase domain. Mutations in the N-ras gene in 11 melanomas were at codon 61 whereas two melanomas carried mutations in codon 12 including a tandem mutation GG>AA. We observed an inverse association between BRAF/N-ras mutations and the frequency of loss of heterozygosity (LOH) on chromosome 9 at 10 different loci. Melanomas with BRAF/N-ras mutations showed a statistically significant decreased frequency of LOH on chromosome 9 compared with cases without mutations (mean fractional allelic loss (FAL) = 0.29±0.23 vs 0.72±0.33; t-test, P = 0.0001). Difference in the FAL value between tumours with and without BRAF/N-ras mutations on 33 loci on five other chromosomes was not statistically significant (mean FAL 0.17±0.19 vs 0.25±0.22; Mest, P = 0.24). Melanoma cases with BRAF/N-ras mutations were also associated with lower age at diagnosis than cases without mutations (mean age 80.38±7.24 vs 65.77±19.79 years; t-test, P = 0.02). Our data suggest that the occurrence of BRAF/N-ras mutations compensate the requirement for the allelic loss at chromosome 9, which is one of the key events in melanoma
I sistemi informativi geografici nella definizione dei terroir vitivinicoli: una applicazione nel terroir della Vernaccia Doc di Serrapetrona (Marche centrali)
No full textIn geomorfologia uno specifico Terroir riassume tutte le caratteristiche dello spazio fisico quali le rocce del substrato, l’evoluzione del suolo, la forma del versante, le specie vegetali e le condizioni climatiche; tali componenti, presi in considerazione insieme, identificano un ambiente univoco e definiscono uno stretto legame tra spazio fisico e produzione vitivinicola.
La rappresentazione quindi di tutte le componenti ambientali che caratterizzano un terroir trovano attualmente giusta applicazione attraverso l’utilizzo dei Sistemi Informativi Geografici.
Infatti, la strutturazione di un sistema informativo territoriale adeguato, costituisce la metodologia migliore per la pianificazione, l’analisi, lo sviluppo e la successiva
rappresentazione cartografica di qualsiasi area oggetto di indagini; questo lavoro di organizzazione dei dati, non costituisce il risultato del lavoro ma il modus operandi, poiché
permette facilmente di immagazzinare, di aggiornare, di validare e di estrarre ogni informazione ritenuta necessaria.
Il presente lavoro si propone di diffondere le peculiarità di un’area vitivinicola, nonché di studiare la connessione fra le caratteristiche territoriali e la quantità/qualità della produzione
vitivinicola locale, attraverso la conoscenza di ogni singola caratteristica geografica, in modo tale da dettagliare il terroir sulla base di ulteriori “requisiti ambientali s.l.” che si vanno a
sommare a quelli insiti nella stessa definizione di terroir.
La zona nel quale si è tentata di applicare questa nuova metodologia è quella interessata alla produzione della Vernaccia DOC di Serrapetrona (vino D.O.C. ufficialmente riconosciuto e
protetto dal D.P.R. del 22-07-71), limitata ad una ristretta area di 45 ha di estensione, ricadente principalmente nel comune di Serrapetrona e in maniera marginale nei comuni di Belforte del
Chienti e di San Severino Marche (Provincia di Macerata).
A tale scopo, saranno utilizzate le più moderne tecniche di analisi offerte dai sistemi informativi territoriali, grazie ad una attenta metodologia di inserimento dei dati, basata sullo sviluppo di
uno schema logico creato ad hoc. All’interno della banca dati locale, realizzata sulla base della Carta Tecnica Regionale alla scala 1:10.000, trovano collocazione: dati di natura geografica
(orografia, idrografia, toponomastica); dati topografici (esposizione dei versanti e loro pendenza); dati geomorfologici (con l’indicazione delle forme, dei processi e dei depositi
riconosciuti); dati geologico-strutturali (distinguendo il substrato e le coperture continentali presenti nell’area complete delle loro caratteristiche litostratigrafiche e mineralogicopetrografiche);
dati idrogeologico-meteoclimatici (con esauriente descrizione delle caratteristiche di permeabilità dei terreni); dati di natura pedologica. In particolare l’attenzione viene rivolta a quelle situazioni morfo-litologiche che possono caratterizzare in maniera più dettagliata e incisiva le differenti caratteristiche pedologiche riscontrabili nell’area della Vernaccia doc, in modo tale che, anche sulla base delle piccole variazioni mineralogico-petrografiche del substrato roccioso, in relazione a situazioni
geomorfologiche differenti, sia possibile ottenere indicazioni sulle caratteristiche pedologiche più idonee per una migliore caratterizzazione del vitigno.
Naturale conclusione del lavoro di analisi, sarà quindi la possibilità di realizzazione di cartografie tematiche estratte dal database, idonee a mettere in evidenza le problematiche
“ambientali” del territorio vitivinicolo (dissesti gravitativi e/o pericolosità geomorfologica in genere), ma soprattutto ad evidenziare le peculiarità dell’area, con la possibilità di realizzare
ulteriori particolari documenti cartografici (quali ad esempio una cartografia dei percorsi geo-eno-gastronomici, ad es.) attraverso la simbolizzazione delle primitive esistenti (punti, linee,
poligoni, region) e l’utilizzo di una legenda evocativa
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