An integrated quantitative framework for supporting product design : the case of metallic moulds for injection

Tese de Doutoramento. Programa Doutoral em Engenharia Industrial e Gestão. Faculdade de Engenharia. Universidade do Porto. 201

POS-Tagging usando pesquisa local

Neste artigo apresenta-se um sistema de part-of-speech tagging, independente do domínio, para etiquetação gramatical de texto para o Português e Inglês. O etiquetador usa informação morfo-sintáctica que vem de um dicionário local que completa a sua informação recorrendo a dicionários disponíveis na rede como o da Priberam e do LookWayUP. Este etiquetador é baseado numa função heurística que é usada na optimização dos seus parâmetros e posterior etiquetação de texto. Na optimização dos parâmetros da função heurística são usadas algumas das técnicas de pesquisa local para reduzir o espaço de pesquisa. Na avaliação do sistema usaram-se dois textos do corpora Reuters: testa (na fase treino) e testb (na fase de teste)

Active Citizenship Through Visual Arts

UIDB/00183/2020 UIDP/00183/2020 UIDB/05021/2020 UIDP/05021/2020Festival Politica is an annual event that started in Lisbon in 2017, and over the years expanded to Braga and Evora, Portugal. Over the years it changed focus from Abstention from Vote, through Human Rights, Europe, and Ecological Sustainability to Frontiers – topics crucial for debate and action throughout our shared global society. But how does one get interested and involved when the overall sentiment is more and more apolitical each year, with alarming numbers among the younger generations – according to the International Institute for Democracy and Electoral Assistance voter turnout has been declining globally for the last thirty years? As a response to these circumstances, Festival Politica decided to promote greater political and social awareness among Portuguese citizens through debates, films, exhibitions, workshops, concerts and activities for children establishing itself as a “showcase and laboratory of the power of citizenship” (https://festivalpolitica.pt/quem-somos/). This article intends to reflect upon the articulation of the concepts of activism and citizenship (Harrebye, 2016; Tascon and Wils, 2016) with the visual arts, especially in cinema and advertising videos. The case study focuses on A Troca, the advertisement video produced by FCB Lisbon Advertising Agency for the last Festival's edition in 2021 (https://youtu.be/Ozkge3fzWo) and on the winning film of the Festival, Chelas Nha Kau produced by Bataclan 1950 collective and Bagabaga Studios. A semiotic analysis (Kress and van Leeuwen, 2006; Saborit, 2012) and content analysis served as the core of the case study, complemented with an interview with Rui Marques, the organizer of the event.publishersversionpublishe

The precision of propex Pixi with different instruments and coronal preflaring procedures

Objective:This study aimed to evaluate the influence of the instrument regarding the apical fit and type of the alloy and coronal preflaring procedures in the accuracy of Propex Pixi.Methods: A total of 40 extracted human single-rooted permanent teeth with apical diameters of 200 mu m were selected. A #10 K-file was inserted in the root canal until its end could be observed by a dental microscope to obtain the actual working length (WL). Electronic measurements were performed using Propex Pixi to the root apex ("0.0"). Different file alloys (stainless steel [SS] and nickel titanium [NiTi]) and sizes (#10, #15, and #20) were used before and after coronal flaring. Statistical analysis was performed by a factorial analysis of variance (P <= 0.05).Results: Results showed that the measurements of electronic length (EL) were closer to the actual working length (WL) after coronal flaring (P<0.05). A significant intraclass correlation was observed between EL and WL. In addition, results showed no significant differences between files with different sizes or alloys.Conclusion: Under the conditions of this study, Propex Pixi demonstrated adequate precision. Its accuracy was enhanced by coronal preflaring procedures regardless of the instrument type used (SS or NiTi) and the apical fit.- (undefined

A new AD/MDO approach to support product design

Nowadays, due to its critical role regarding product cost and performance, as well as time to market, product design is considered to be at the new frontiers for achieving competitive advantage. Therefore, to face todays rapidly changing business environments, it is extremely important to adopt a systematic approach to product design, in order to avoid errors and consequently achieve shorter time-to market performances. In this context, we will describe a new approach to support product design, which links Axiomatic Design (AD) and Multidisciplinary Design Optimization (MDO), applied in an integrated way at the conceptual design and the detailed design stages, respectively. Firstly, the conceptual design stage is undertaken by AD, which is used to map Functional Requirements (FRs) with the corresponding Design Parameters (DPs). Even though we try to guarantee the Independence of FRs, as established by Axiom 1 of AD, if some remaining coupled relations subsist that is not prohibitive. Afterwards, the detailed design is carried out by MDO, considered to be an appropriate methodology to design complex systems through an adequate exploitation of interacting phenomena. The proposed approach is applied to the design of metallic moulds for plastic parts injection, since the mould makers sector involves constant design and production of unrepeatable moulds, where uncoupled design solutions, mostly due to technological and time reasons, arent common (this sector is strongly influenced by customers who place enormous pressures on lead-time and cost reduction). This application points out the high potential of improvement that can be achieved through the simultaneous improvement of mould quality, reliability and time to market

Effect of Gutta-percha Solvents on the Bond Strength of Sealers to Intraradicular Dentin: A Systematic Review

Introduction: The aim of our systematic review was to assess the impact of gutta-percha solvents on the bond strength of endodontic sealers to intraradicular dentin using the push-out bond test. Methods and Materials: The literature was searched in databases (PubMed, Web of Science and Scopus) up to September 2020, using the following search terms: (bond strength AND solvent* AND sealer* AND (tooth root OR dentin OR retreatment OR root canal). No date limits were implemented, and English languages were included. The question research was constructed based on the PICO (Population, Intervention, Comparison, and Outcome) strategy: “Does gutta-percha solvents effect the bond strength of sealers to intraradicular dentin?”. The studies were analyzed by two reviewers and were included if they utilized extracted permanent human teeth with completely formed apices, as well as assessed the influence of gutta-percha solvents on the bond strength of sealers to intraradicular dentin using push-out bond test. Review articles, case reports and studies that included immature, bovine or artificial teeth were excluded. The risk of bias was evaluated based on the Cochrane criteria adopted to in vitro studies.&nbsp; Results: Thirty-two papers were analyzed, seven accomplished the eligibility criteria and were selected for our systematic review. The global risk of bias was high. Due to variations in the methodological variables, a meta-analysis could not be performed. Conclusion: Our systematic review highlighted the adverse effect of chloroform, which decreased the bond strength of different sealers, and the generally higher bond strength of epoxy resin-based sealers, detected with the push-out bond test. We recommend the standardization of methods in future studies to obtain a more definitive conclusion about the influence of solvents on the bond strength of sealers to intraradicular dentin

Avaliação da qualidade de tratamentos endodônticos realizados por estudantes de Medicina Dentária

Objectives: To assess radiographically the technical quality of root fillings placed by undergraduate students at the Faculty of Dental Medicine of the University of Porto. Methods: The records of 318 patients were assessed, of which 225 radiographs of root canal fillings in single-rooted teeth were selected. The radiographs were examined using the VixWin Platinum v1.1 Imaging Software (Gendex, USA). The quality of root canal filling was graded as "acceptable" when both length and density were adequate. Procedural errors were registered. Chi-square tests were used for statistical analysis, considering a 0.05 significance level. Results: Root canal fillings were considered acceptable in 53.3% of the cases. There was a greater percentage of adequate density (70.7%) than adequate length (64%). There was a statistically significant association between the quality of the filling and the type of tooth, with maxillary anterior teeth presenting higher quality (p=0.027). The most common reason for inadequate length was short-filling (33%). There was a statistically significant relationship between the academic year and the density of the fillings (p=0.009). Overall procedural errors occurred in 3.6% of the cases, with the most common being ledge formation and apical transportation. Conclusions: The quality of root canal fillings in single-rooted teeth performed by junior dental students at the University of Porto was considered acceptable in 53.3% of cases.Objetivos: Avaliar radiograficamente a qualidade das obturações de tratamentos endodônticos realizados por estudantes do Mestrado Integrado da Faculdade de Medicina Dentária da Universidade do Porto. Métodos: Foram avaliados os registos de 318 pacientes, dos quais foram selecionadas 225 radiografias periapicais de dentes monorradiculares. As radiografias foram examinadas utilizando o software de imagem VixWin Platinum v1.1 (Gendex, EUA). A qualidade do tratamento endodôntico foi classificada como "aceitável" quando o comprimento e a densidade estavam adequados. Os erros iatrogénicos foram registados. O teste qui-quadrado foi utilizado para análise estatística, considerando um nível de significância de 0,05. Resultados: O tratamento endodôntico foi considerado aceitável em 53,3% dos casos. Houve uma maior percentagem de densidade adequada (70,7%) do que comprimento adequado (64%). Verificou-se uma associação estatisticamente significativa entre a qualidade da obturação e o tipo de dente, sendo os dentes anteriores superiores a apresentar maior qualidade (p = 0,027). A razão mais comum para o comprimento inadequado foram as obturações curtas (33%). Verificou-se uma relação estatisticamente significativa entre o ano letivo e a densidade da obturação (p = 0,009). Erros iatrogénicos ocorreram em 3,6% dos casos, sendo os mais comuns a formação de degraus e o transporte apical. Conclusões: A qualidade dos tratamentos endodônticos em dentes monorradiculares realizados por estudantes de Medicina Dentária da Universidade do Porto foi considerada aceitável em 53,3% dos casos.- (undefined

Plasma Treatment on Root Canal Sealers' Adhesion to Intraradicular Dentin - A Systematic Review

This investigation aimed to assess, through a systematic review, the effect of non-thermal plasma treatments on root canal sealers’ adhesion to dentin. This study followed the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature search was undertaken without limits on time or language, until May 2023, in PubMed–MEDLINE, Scopus, Web of Science, OpenGrey, and three endodontic journals. The included studies underwent quality assessment and data extraction. Out of an initial 188 articles, 4 studies were included. Three of these studies based the adhesion ability on the push-out test in human extracted teeth, while the other used bovine dentin samples to measure the contact angle with the sealer (wettability). While there was no consensus about the effect of non-thermal plasma (NTP) on the AH Plus sealer’s adhesion to radicular dentin, NTP seemed to positively influence the adhesion ability of BioRoot RCS and Endosequence BC. The findings of the present review should be interpreted cautiously due to the scarcity of studies on the topic. The NTP parameters should be optimized to obtain a stronger evidence base in endodontics on its role as an adjuvant tool to increase sealers’ adhesion to dentin.This article was supported by National Funds through the FCT—Fundação para a Ciência e a Tecnologia, I.P., within CINTESIS, R&D Unit (reference UIDP/4255/2020)