1,721,231 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
The future, new serotypes, new methods of diagnosis, and other methods of control
No full textThe paper reviews the new methods of diagnosis and control of Avian Pneumovirus infections in birds
Construction of a green fluorescent protein (GFP) Avian Metapneumovirus (AMPV) recombinant lacking the small hydrophobic (SH) protein gene shows that giant syncytial formations are not a result of the reduction in genome size
No full textAn AMPV reverse-genetics system was used to create a virus lacking the entire SH open reading frame which produced unusual giant syncytial formation in cell culture. The replacement of the gene with GFP resulted in virus which also produced the same syncytial formation. The intrinsic fluorescent properties of the virus may prove useful in pathogenesis studies. The similarity of size of the 2 genes suggests that the altered cytopathic effect did not result from the shortening of the genome and possible consequential effects on the transcription or translation of the following attachment and polymerase protein genes
New PCR test for the molecular detection of avian pneumovirus
No full textThis study described the design and sensitivities of PCR tests used to detect DNA copies of an A type avian pneumovirus (APV). The objective was selection of PCR primer combinations which would provide the greatest test sensitivity for later testing of field materials. Sensitivities could be determined because of laboratory access to known quantities of purified full length DNA copies of a complete APV genome. Four new nested PCR tests were designed in the fusion (F) protein [2 tests], small hydrophobic (SH) protein and nucleocapsid (N) protein genes and compared to an established test in the attachment (G) protein gene. Sensitivities were found to differ between the tests with the most sensitive being the established G test. When one of the F PCRs was modified to position pyrimidine residues at all primer 3’ termini, its sensitivity exceeded that of the established G test and was chosen for use in future diagnostic testing
Sviluppo di un clone infettante di Metapnumovirus aviare codificante la proteina GFP (Green Fluorescent Protein).
No full textConstruction of GFP Avian Metapneumovirus (AMPV) recombinant lacking the small hydrophobic protein gene
No full textAn AMPV reverse-genetics system was used to create a virus lacking the entire SH
open reading frame which produced unusual giant syncytial formations in cell culture.
The replacement of the gene with GFP resulted in virus which also produced the
same syncytial formations. The intrinsic fluorescent properties of the virus may prove
useful in pathogenesis studies. The similarity of size of the 2 genes suggests that the
altered cytopathic effect did not result from the shortening of the genome and
possible consequential effects on the transcription or translation of the following
attachment and polymerase protein genes
Sviluppi di un clone infettante di Metapneumovirus aviare codificante la proteina GFP (Green Fluorescent Protein)
No full textMetapneumovirus aviare (AMPV) è causa nel tacchino di una delle principali patologie di questa specie nota come Rinotracheite del Tacchino (TRT). Per la profilassi della TRT sono disponibili in commercio da oltre 15 anni vaccini vivi attenuati con metodi tradizionali, che hanno portato ad un netto miglioramento del controllo della malattia. Tuttavia ancora rimangono dubbi sulle performance di tali vaccini specie in condizioni di campo. Si è osservata ad esempio la tendenza a riacquisire patogenicità e tale fenomeno sembra essere la diretta conseguenza di mutazioni genetiche anche minime. Recentemente è stato messo a punto un sistema di reverse genetics per AMPV sottotipo A, che permette di introdurre in punti specifici del genoma mutazioni o delezioni, di ottenere cloni infettanti con i cambiamenti apportati e di valutarne le conseguenze fenotipiche. Tale sistema fornisce uno strumento fondamentale per indagare le basi molecolari della patogenicità, e più in generale per studiare la biologia del virus. Questo lavoro descrive l’utilizzo del sistema di reverse genetics per generare un AMPV-A ricombinante che esprima la proteina fluorescente GFP (Green Fluorescent Protein). In cDNA circolarizzato derivato da AMPV-A è stato inserito un sito di restizione mediante mutagenesi sito-specifica. Dopo taglio enzimatico è stato inserito in tale plasmide il gene che codifica per GFP. L’avvenuta ligazione, dopo trasformazione batterica, è stata verificata mediante screening delle singole colonie con specifiche PCR e successivo sequenziamento. Copie del plasmide purificato sono state trasfettate in cellule VERO con l’aggiunta di plasmidi di supporto che codificano per il complesso delle proteine ribonucleari (RNP). L’espressione della GFP è stata confermata mediante osservazione di fluorescenza al microscopio UV. Inoltre i risultati ottenuti mostrano come AMPV-A può essere manipolato geneticamente, grazie al sistema di reverse genetics, per esprimere stabilmente proteine estranee, mostrando un grosso potenziale di utilizzo quale vaccino vettore di proteine virali appartenenti a virus patogeni per i volatili o i mammiferi. Inoltre la disponibilità di AMPV-A esprimente la proteina fluorescente GFP potrà essere utile per studi di tropismo e patogenesi
- …
