1,720,998 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
Influence of modified titanium abutment surface on peri-implant soft tissue behavior: A systematic review of in vitro studies
No full textAbutment soft tissue integration in the transmucosal area supports the peri-implant tissues, improves esthetics, ensures a soft tissue seal against microorganisms, and preserves crestal bone level. The aim of this systematic review was to systematically analyze the cellular response of fibroblasts on different abutment materials and surface modifications in in vitro studies with a score-based reliability evaluation.Purpose: Abutment soft tissue integration in the transmucosal area supports the peri-implant tissues, improves esthetics, ensures a soft tissue seal against microorganisms, and preserves crestal bone level. The aim of this systematic review was to systematically analyze the cellular response of fibroblasts on different abutment materials and surface modifications in in vitro studies with a score-based reliability evaluation. Materials and Methods: A protocol aiming to answer the following focused question was developed: "What is the effect of different abutment materials and different surface modifications on in vitro cellular response of fibroblasts?" A search through three electronic databases (Medline/PubMed, EMBASE, and Web of Science) was performed using the following search terms: fibroblast, implant, abutment used as the main keywords, with AND/OR as Boolean operators. Only in vitro studies using machined titanium as control surface were included. A quality assessment of the selected studies was performed following the SciRAP method. Results: Out of a preliminary pool of 97 articles, 21 relevant articles were identified for final evaluation. Cellular response evaluation was investigated as follows: 10 studies compared two or more different materials, 7 assessed mechanical surface modification, 14 weighed chemical or biochemical surface modification, and 3 evaluated surfaces modified by a biophysical procedure. Rather than abutment bulk material, external surface features (collagen coating, electropolishing, plasma cleaning, and laser dimpling) were demonstrated to positively affect cell response (cell attachment, morphology and proliferations, expression of adhesion-related proteins and cytokines), mostly at the early stage. While sandblasting, acid etching, composite coating, nitride coating, and vitamin D presented lower results compared with machined, controversial results were demonstrated by anodization. The mean reporting quality SciRAP score was 78.17 ± 11.89, while the mean methodologic quality SciRAP score was 84.13 ± 12.35. Intrastudy comparison highlighted that the time after seeding chosen to evaluate the fibroblast response varies significantly and seems to deeply influence the response. In fact, due to heterogeneity in the study designs, statistical methods, and reported results, meta-analysis of the data was not possible. Conclusion: Within the limitation due to the design and heterogeneity of the included studies, it can be speculated that abutment material and its mechanical, physical, and chemical modification influence fibroblast response in vitro, especially in the earlier phases of contact with the abutment surface
Virulence factors of periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia
No full textINTRODUZIONE
Le malattie parodontali (MP) sono patologie
infettivo-infiammatorie delle strutture
anatomiche di sostegno del dente, cioè
gengiva, legamento parodontale, osso alveolare
e cemento radicolare [Academy
Reports, 1999]. Vengono distinte in gengiviti
e parodontiti.
Le gengiviti sono caratterizzate da rossore,
edema, sanguinamento, alterazione del
contorno gengivale e incremento del flusso
di fluido creviculare. La comparsa della
gengivite richiede l’accumulo di placca
batterica che direttamente o indirettamente
provochi un’alterazione patologica dei
tessuti. L’analisi istopatologica ha individuato
tre fasi nell’evoluzione della malattia:
la fase iniziale dove è già possibile evidenziare
degradazione del collagene, alterazioni
nei vasi e nelle cellule epiteliali
con presenza di un caratteristico infiltrato
di neutrofili. La seconda fase è caratterizzata
da un massiccio infiltrato linfoide nel
quale predominano i linfociti T, mentre
nella terza fase predominano i linfociti B.
Le parodontiti si distinguono clinicamente
dalle gengiviti per la presenza di perdita di
attacco connettivale al dente associata ad infiammazione
gengivale. E’ presente perdita
di legamento parodontale e riassorbimento
d’osso alveolare contemporaneamente a migrazione
dell’attacco epiteliale lungo la superficie
radicolare. Actinobacillus actinomycetemcomitans,
Porphyromonas gingivalis e
Prevotella intermedia sono batteri implicati
nell’etiologia delle parodontiti e rappresentano
un importante fattore di rischio per la
progressione delle stesse [Wolff et al., 1994]
La parodontite giovanile da Actinobacillus actinomycetemcomitans. Diagnosi molecolare con identificazione dei genotipi virulenti
No full text
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
Oligonucleotidi da utilizzare come primer in PCR per il rilevamento di batteri patogeni parodontali, kit comprendenti tali oligonucleotidi e metodo per il loro uso
No full textIl brevetto riguarda la progettazione e il comportamento in esperimenti di laboratorio di oligonucleotidi utilizzabili nelle metodiche di PCR e nella PCR quantitativa real time , per il rilevamento di alcuni batteri associati alla malattia parodontale (piorrea)
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
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