1,720,982 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Diagnostic mutation analysis in hypertrophic cardiomyopathy by DNA resequencing array
No full textPurpose: Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease (1/500) characterized by a remarkable clinical and genetic heterogeneity. More than 450 different pathogenic mutations in at least 20 genes have been identified so far. Genetic testing for HCM has a growing impact on the medical management of patients and their families, however routine diagnostic mutation analysis by classical methods remains very time-consuming and expensive.
Methods: We have developed a 30 Kbp HCM-DNA-resequencing-array (CustomSeq Affymetrix) for all exons (n=160), splice-sites and 5'-UTR of 12 HCM genes, which we currently use for mutation analysis in clinical practice. This HCM-array is very efficient to detect single nucleotide substitutions accounting for up to 86% of all HCM mutations. Actually it does not detect small indels.
Results: We analysed 115 patients from 5 different centres. Overall, we identified 30 different single nucleotide substitutions in the coding regions or splice sites of MYH7, MYBPC3, TNNT2, TNNI3, TPM1 and MYL3 in 42 patients (37%). Twelve variants were reported as known mutations and 14 were novel changes not found in a control population study (>200 chromosomes). Furthermore, we identified 4 known SNPs/variants previously reported as mutations for HCM.
Conclusions: Our DNA resequencing array appears to date as the most rapid and cost-effective technology for mutation screening in HCM. Further improvement of the software may detect small insertions/deletions in the future. The HCM-array provides a first attempt of high throughput sequencing methodology which will further develop and probably become the method of choice for routine molecular diagnosis of heterogeneous disorders such as HCM
Ricerca di mutazioni patogene in pazienti affetti da cardiomiopatia ipertrofica: risultati dello screening genetico per 12 geni con tecnica di DNA resequencing array.
No full textBackground. La cardiomiopatia ipertrofica (CMI) rappresenta la più
frequente malattia cardiaca geneticamente determinata, ha
trasmissione di tipo autosomico dominante ed ampia eterogeneità
genetica e clinica. Finora sono state identificate più di 450 diverse
mutazioni a carico di geni codificanti proteine del sarcomero cardiaco,
del disco z, dei dischi intercalati, proteine coinvolte nel metabolismo
cardiaco e nell’omeostasi del calcio. L’analisi genetica costituisce un
utile strumento diagnostico nella CMI, in quanto consente di chiarire o
confermare la diagnosi e, qualora venga estesa ai familiari del
probando, permette di identificare i soggetti asintomatici a rischio di
sviluppare la malattia, tuttavia rimane uno strumento costoso,
prerogativa di pochi centri. La ricerca di mutazioni nel DNA mediante
tecnica di resequencing array è un sistema innovativo che consente lo
screening contemporaneo di un elevato numero di geni con notevole
risparmio di tempo e denaro rispetto al metodo tradizionale di
sequenziamento diretto, consentendo la diffusione dello screening
genetico anche ad ampie popolazioni di soggetti affetti.
Scopo. Utilizzare la tecnica di DNA resequencing array (30 kb) per
ricercare mutazioni patogene in una popolazione di pazienti affetti da
CMI analizzando ampie regioni esoniche, siti di splicing e promotori di
12 geni candidati.
Metodi. 35 casi indice affetti da CMI (21 maschi, 28 forme familiari, 16
ostruttive, età media 39±15 anni) sono stati sottoposti, previo consenso
informato, a screening di mutazioni in 160 regioni esoniche, oltre a siti di
splicing e promotori di 12 geni candidati (MYH7, MYBPC3, MYL3, MYL2,
TNNI3, TNNT2, TNNC1, TPM1, ACTC, CSRP, PLN, PRKAG2) mediante tecnica
di DNA resequencing array. Le mutazioni identificate sono state poi
confermate mediante sequenziamento diretto ed, in caso di mutazioni
nuove, queste sono state ricercate in 200 controlli sani per escludere che si
trattasse di polimorfismi. Tutti i pazienti sono stati sottoposti a visita
cardiologica, ECG di base e dinamico secondo Holter, ecocardiogramma
ogni 6-12 mesi per un follow up medio di 12±9 anni (range 1 mese-25 anni).
Risultati. Otto diverse mutazioni patogene (di cui 4 nuove) sono state
riscontrate in 9 pazienti (26%), di queste 3 (37%) erano a carico del gene
MYBPC3 codificante la proteina C legante la miosina, 1 (11%) del gene
MYH7 per la catena pesante della miosina, 1 (11%) del gene TNNI3 ed 1
(11%) del gene TNNT2 rispettivamente per la troponina cardiaca I e T, 1
(11%) del gene MYL3 per la catena leggera essenziale della miosina ed 1
(11%) del gene PLN per il fosfolambano. Inoltre sono stati riscontrati 9
polimorfismi in 12 pazienti (34%), in 2 casi associati a mutazione di
MYBPC3 o TNNI3. Tutte le mutazioni identificate mediante DNA
resequencing array sono state confermate mediante sequenziamento
diretto. Una paziente portatrice di una mutazione nel geneMYBPC3
(Ala364Thr) è stata sottoposta a trapianto cardiaco per insufficienza
cardiaca progressiva, una (MYBPC3, Thr704Lys) è deceduta per morte
improvvisa ed un’ altra portatrice di mutazione nel gene TNNI3
(Arg186Gln) è stata rianimata da arresto cardiaco.
Conclusioni. La tecnica di analisi genetica mediante DNA resequencing
array rappresenta attualmente la strategia più rapida ed economica
per lo screening di mutazioni in patologie ad ampia eterogeneità
genetica quali la CMI. Essa attualmente costituisce un sistema affidabile
per l’identificazione di singole mutazioni e sviluppi futuri la
renderanno utilizzabile anche per riconoscere inserzioni e delezioni
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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