1,720,956 research outputs found
A literature review of endotoxin removal from inside of root canals by rotary systems
No full textBactérias anaeróbias estritas Gram-negativas têm sido isoladas de canais necróticos. Estes
microorganismos possuem lipopolissacarídeos (LPS) ou endotoxinas em sua parede
celular, responsáveis por efeitos tóxicos. Sistemas rotatórios vêm sendo cada vez mais
utilizados no preparo químico-mecânico em Endodontia. O objetivo deste trabalho foi revisar
a literatura acerca da eliminação de endotoxinas do interior de canais radiculares por siste-
mas rotatórios O preparo químico-mecânico tem como principal objetivo a eliminação de
bactérias. Entretanto, para obtenção de sucesso, deve almejar também a eliminação de
endotoxinas. Como um importante avanço em Endodontia, destacam-se os sistemas
rotatórios com limas de níquel-titânio. Graças à sua maior flexibilidade, excelente capaci
-
dade de corte e redução do estresse em longas consultas, os mesmos têm tido sua
utilização muito difundida. Entretanto, pôde-se observar no presente estudo que poucas são
as pesquisas que avaliaram sua ação em relação ao LPS. Concluiu-se que o uso de instru-
mentos rotatórios, com maior diâmetro de ponta, proporciona redução de endotoxinas do
canal radicular, entretanto, não foi capaz de promover sua total eliminação.Anaerobic Gram-negative bacteria has been isolated from necrotic root canals. These
microorganisms have lipopolysaccharide (LPS), endotoxin, in their cell wall which are
responsable for their toxic effects. Rotary systems have been increasingly used in
chemical-mechanical preparation in Endodontics. The aim of this research was to review the
literature about endotoxin removal from inside of root canals using rotary systems. The
chemical-mechanical preparation is the essential part of this therapy and has its goal on
eliminating bacteria. However, to reach success of the endodontic therapy,
chemo-mechanical preparation should also aim endotoxin removal. As an important step
forward in Endodontics, we highlight the rotary systems with nickel-titanium. Thanks to its
flexibility, excellent cutting ability and stress reduction in long sessions of treatment, they
have been widely used. However, it was seen in this research that few studies have
evaluated their action on bacterial LPS. In conclusion, the use of rotary instruments with
larger diameter of the tip, provides endotoxin removal from the inside of root canal, however,
they were not able to reach LPS complete elimination
Estudo ex vivo na remoção da smear layer com agitação e sem agitação do EDTA 17% e ácido cítrico 10%: análise em MEV
No full textA remoção da smear layer favorece a penetração de agentes desinfetantes no interior dos túbulos dentinários e promove melhor adaptação dos materiais obturadores endodônticos. O objetivo deste estudo, ex vivo , foi avaliar a remoção da smear layer com e sem agitação do EDTA 17% e ácido cítrico 10%. Vinte e cinco caninos humanos recém-extraídos foram instrumentados e divididos aleatoriamente em cinco grupos, de acordo com o protocolo de irrigação final: G1 – 5 ml de Ácido cítrico 10% por 1minuto sem agitação + 5 ml de NaOCl 6% ; G2 – ácido cítrico 10% associado à agitação com guta- percha por 1 minuto + NaOCl 6%; G3 - EDTA 17% por 1 minuto sem agitação + NaOCL 6%; G4 – EDTA 17% associado à agitação com guta -percha por 1 minuto + NaOCl 6%; G5 – 10 ml de NaOCl 6 % (controle positivo). Os espécimes foram clivados longitudinalmente e preparados para análise do terço apical em Microscópio Eletrônico de Varredura (MEV). Os dados foram analisados com os testes de Kruskal-Wallis e comparações múltiplas de Dunn. De acordo com os resultados da análise estatística, quando comparados entre os grupos, dois a dois, houve diferença entre os Grupos III e V, em relação ao Grupo IV. Os Grupos III e V não foram capazes de remover a smear layer. Não houve diferença estatisticamente significante entre os Grupos I, II e IV. Concluiu-se que não houve diferença entre os grupos quanto a remoção da smear layer, a exceção do grupo em que se utilizou EDTA 17% sem agitação, tendo este sido incapaz de remover a smear layer da parede dentinária.Monografia (Especialização em Endodontia) – Odontoclínica Central da Marinha.The removal of the smear layer favors the penetration of disinfecting agents within the dentinal tubules and promotes better adaptation of endodontic filling materials. The purpose of this study, ex vivo, was to evaluate the smear layer removal with and without agitation EDTA 17% and 10% citric acid. Twenty-five freshly extracted human canines were instrumented and randomly divided into five groups according to the protocol irrigation end: G1 - 5 ml of 10% citric acid per 1 minute without agitation and 5 ml of 6% NaOCl, G2 - acid 10% citric associated with gutta-percha agitation for 1 minute 6% NaOCl +, G3 - 17% EDTA for 1 minute without stirring NaOCl + 6%; G4 - 17% EDTA with agitation associated with gutta-percha + NaOCl for 1 minute 6%; G5 - 10 ml of 6% NaOCl (positive control). The specimens were cleaved longitudinally and prepared for analysis in the apical third Scanning Electron Microscope (MEV). Data were analyzed with the Kruskal-Wallis and Dunn multiple comparison. According to the results of the statistical analysis, comparison between the groups, two by two, there was no difference between Groups III and V, as compared to Group IV. Groups III and V were not able to remove the smear layer. There was no statistically significant difference between Groups I, II and IV. It was concluded that there was no difference between the groups regarding the removal of the smear layer, except the group which used 17% EDTA without agitation, the latter has been unable to remove the smear layer of dentin wall
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
Efeito das soluções de EDTA 17% e ácido cítrico 10% através da agitação manual e ultrassônica na remoção da smear layer: análise em MEV
No full textA instrumentação do canal radicular produz a smear layer que cobre a superfície da parede do canal preparado. A remoção da smear layer tem sido o foco de muitos estudos na tentativa de alcançar o máximo do preparo químico-mecânico. Este estudo ex vivo teve por objetivo avaliar a efetividade de diferentes protocolos de irrigação final na remoção da smear layer e formação de erosão na dentina intraradicular. Trinta e cinco caninos humanos extraídos foram instrumentados e randomicamente divididos em 7 grupos, de acordo com o protocolo de irrigação final usado: G1 (ED3M) e G3 (ED3US), EDTA 17% por 3 minutos com agitação manual e ultrassônica, respectivamente; G2 (CA30M) e G4 (CA30US), ácido cítrico 10% por 30 segundos com agitação manual e ultrassônica, respectivamente; G5 (CA3M) e G6 (CA3US), ácido cítrico 10% por 3 minutos com agitação manual e ultrassônica, respectivamente; e G7 (Na3), NaOCl 5,25% por 3 minutos sem agitação (controle). Em seguida, todos os espécimes foram irrigados com NaOCl 5,25%. Os espécimes foram então esplintados longitudinalmente e observados sob Microscópio Eletrônico de Varredura (MEV) nos terços cervical, médio e apical. Os dados foram analisados com os testes de Kruskal-Wallis e Mann-Whitney. A eficácia do EDTA 17% e ácido cítrico 10%, na remoção da smear layer, foi significativamente maior que o NaOCl
5,25% (controle). Não houve diferença significativa entre os protocolos de irrigação final testados na remoção da smear layer e efeitos erosivos. Entretanto, quando comparado os três terços, dentro de cada grupo, no G1 (ED3M) e G2 (CA30M), houve uma menor limpeza da smear layer e formação de erosão no terço apical. Quando comparado o terço apical entre os grupos, o G4 (CA30US) foi mais efetivo que o G1 (ED3M) (p=0.0004), G2 (CA30M) (p=0.0018) e G3 (ED3US) (p=0.0003) na remoção da smear layer. Concluiu-se que os protocolos usados neste estudo foram similares, tanto na remoção da smear layer quanto nos efeitos erosivosRoot canal instrumentation produces smear layer which covers the surfaces of prepared canal walls. Removal of the smear layer has been the focus of many studies in an effort to achieve the ultimate chemomechanical preparation. The aim of this ex vivo study was to evaluate the effectiveness of different final irrigation protocols in smear layer removal and erosion in intraradicular dentine. Thirty five extracted human canines were instrumented and randomly divided, according to final rinse techniques used, into 7 groups: G1 (ED3M) and G3 (ED3US), 17% EDTA for 3 minutes with manual and ultrasonic agitation, respectively; G2 (CA30M) and G4 (CA30US), 10% citric acid for 30 seconds with manual and ultrasonic agitation, respectively; G5 (CA3M) and G6 (CA3US), 10% citric acid for 3 minutes with manual and ultrasonic agitation, respectively; and G7 (Na3), 5.25% NaOCl for 3 minutes without agitation (control). Next, all specimens were irrigated with 5.25% NaOCl.
Specimens were then split lengthwise and observed under Scanning Electron Microscope (SEM) in apical, middle and coronal thirds. Data were analyzed with Kruskal-Wallis and Mann-Whitney tests. The efficacy of 17% EDTA and 10% citric acid in removing smear layer was significantly greater than 5.25% NaOCl (control). There were no significant differences among final irrigation tested protocols in removing the smear layer and erosive effects. However, when compared the three thirds, inside of each group, in G1 (ED3M) and G2 (CA30M), least smear layer removal and erosion formation was showed in the apical third. When compared the apical thirds, group 4 (CA30US) was more effective than G1 (ED3M) (p=0.0004), G2 (CA30M) (p=0.0018) and G3 (ED3US) (p=0.0003) in smear layer removal. In
conclusion, the protocols used in this study were similar in the smear layer removal as well as in erosive effects73f
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
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
- …
