A carregar...
4 resultados
Resultados da pesquisa
A mostrar 1 - 4 de 4
- Mechanical and surface properties of a 3D-printed dental resin reinforced with graphenePublication . Salgado, Helena; Fialho, Joana; Marques, Marco; Vaz, Mário; Figueiral, Maria; Mesquita, PedroObjectives: Commercial photocurable polymers used in dental additive manufacturing still have mechanical limitations. The incorporation of graphene may provide interesting advantages in this field. This study aimed to evaluate in vitro the effect of adding graphene nanoparticles to a 3D-printed polymethylmethacrylate dental resin in terms of surface roughness, flexural properties, and hardness. Methods: A 3D-printed dental resin (Dental Sand, Harz Lab) was loaded with four different graphene nanoplatelet (Graphenest) concentrations: 0.01wt%, 0.1wt%, 0.25wt%, and 0.5wt%. The neat resin was used as the control group. The surface roughness was measured with a contact profilometer using bar-shaped specimens (50x10x4mm). The flexural strength of specimens (80x10x4mm) from each group was calculated using the 3-point bending test in a Universal Test Machine. Hardness shore D was measured using a manual durometer on round-shaped specimens (12x6mm). Data were evaluated using the Kruskall-Wallis test followed by post-hoc Bonferroni corrected pairwise inter-group comparisons. Statistical significance was set at p<0.05. Results: Graphene improved 3D-printed PMMA resin hardness with statistical significance at a concentration of 0.01wt% (p=0.043). Surface roughness increased with graphene concentrations above 0.01wt%, with statistically significant differences at 0.25wt% (p=0.006) and 0.5wt% (p=0.005) concentrations. Flexural properties worsened with increased graphene concentrations, and these differences were significant in the concentrations of 0.25wt% (p=0.028) and 0.5wt% (p=0.006). Conclusions: The use of graphene as a mechanical reinforcement nanomaterial seems to be viable at low concentrations without prejudice to the surface roughness of a 3D-printed polymethylmethacrylate resin. (Rev Port Estomatol Med Dent Cir Maxilofac. 2023;64(1):12-19)
- Process Mining in a Line ProductionPublication . Santos, Cristina; Fialho, Joana; Silva, Jorge; Neto, TeresaThe search for more efficient strategies, cost savings, time optimization and productivity are the main goals of any successful company. Process mining arises in this context and, although it is not a new concept, its expansion and applicability in the market has recently become notorious. Through an extensive set of data recorded over time, it is possible to determine the real state of a company's processes, allowing to diagnose failures and improve the efficiency of these processes. This paper describes a project realized in the scope of process mining, developed in the company Huf Portuguesa. The machines of a production line record thousands of data. In a specific production line, data was collected in a time range, cleaned and processed. Process mining techniques allowed the discovery and analysis of the real state of the production line. All paths were detected, and each path was analyzed individually. The conformity was also analyzed.
- SSENPV's Integrated Management PlatformPublication . Pinto, Bruno; Matos, Cristina Peixoto; Abrantes, Steven; Lourenço, Carolina; Fialho, Joana; Cravo, Ivone; Antunes, Maria José; Nascimento, MárcioAt the Polytechnic of Viseu (PV) [1], the number of students has been increasing [2], and it is hoped that this trend continues, for the sake of the literacy of the population that serves in its area of coverage and for the reduction of the desertification of the interior region in which is inserted. In the case of Students with Specific Educational Needs (SSEN) who attend the PV (SSENPV), it is extremely important to develop procedures that minimize the anxiety brought about by change for these students, as well as to facilitate their adaptation, to make the period of permanence in Higher Education (HE) an inclusive period, generating well-being, promoting academic success, and facilitating the transition to active life. To combat this phenomenon and since the PV is a Higher Education Institution (HEI) that is guided by equity in its community, in particular the student community, the SSENPV census is a crucial measure insofar as it is necessary to implement procedures, which must respect and obey individual specificities. It is also intended that, regarding access to information on the platform, it will allow reducing asymmetries between students as well as access to services. To respond to this reality, within the scope of the Inova & Includes project. IPV I2 [3], a group of researchers, in partnership with the degree course in Computer Engineering at the Superior School of Technology and Management of Viseu (ESTGV) – curricular unit of “Project”, developed an integrated management platform for SSENPV. This platform, which is intended to be a contribution to true equity in education in the PV, is based on the support of social impact in different dimensions, which translates into the implementation of the following profiles: • Informative Profile: dissemination of legislation and other relevant information on Specific Educational Needs (SEN), ensuring centralized and accessible information management and streamlining procedures and support measures. • Academic Profile: registration and updating of data on the SSENPV. • Technical Evaluation and Follow-up Profile: registration of the SSENPV procedural evaluation, with automatic sending of technical evaluations to authorized users
- Sleep Quality among Medical Students of a Portuguese UniversityPublication . Ferreira, Rita; Brás, João; Fialho, Joana; Peixoto, CristinaIntrodução: O sono é um processo fisiológico complexo presente na maioria dos seres vivos. As perturbações do sono têm vindo a aumentar exponencialmente. Os estudantes universitários, particularmente, os estudantes de medicina, são especialmente vulneráveis a esta problemática. Contudo, a literatura existente relativa ao tema é escassa, especialmente, em Portugal. O objetivo deste estudo consiste em avaliar a qualidade de sono nos estudantes do curso Medicina da Universidade da Beira Interior, Covilhã, Portugal e analisar as diferenças e relações existentes de acordo com a idade, sexo, coabitação e ano de curso. Métodos: Trata-se de um estudo transversal em que os estudantes envolvidos preencheram o Índice da Qualidade de Sono de Pittsburg (PSQI), previamente validado para a população portuguesa. Os valores obtidos, para cada componente do PSQI, foram inicialmente analisados para a população global, e posteriormente relacionados com as variáveis sociodemográficas, visando a obtenção de relações estatisticamente significativas. Resultados: Duzentos noventa seis estudantes responderam ao questionário. Destes, 62,2% consideraram o seu sono bom; 42,4% obtiveram 1 na componente latência do sono; 50% admitiu dormir entre 6 a 7 horas; 73,9% evidenciou uma eficiência de sono adequada; 85,5% relatou pouco ou nenhum distúrbio do sono; 83,8% referiu nunca ter usado medicação para dormir; e 60,8% mencionou pouca ou nenhuma disfunção diurna. Relativamente ao PSQI global, 73,1% dos estudantes obtiveram uma pontuação superior a 5, indicando uma má qualidade de sono. Das raparigas, 74,7% e dos rapazes, 67,7% revelaram uma pobre qualidade de sono. Dos estudantes, que vivem sozinhos, 91,3% também exibiram uma pobre qualidade de sono. Relativamente ao ano letivo do curso no qual o inquérito foi aplicado, 82,4% dos estudantes do 1º ano reportaram uma pobre qualidade de sono, assim como 77,5% do 2º ano, 72,1% do 3º, 77,8% do 4º, 65,8% do 5º e 71,4% do 6º ano do curso. Conclusão: Globalmente, os estudantes que participaram neste estudo apresentaram má qualidade de sono, com uma classificação no PSQI superior 5. Contudo, as classificações em cada um dos componentes não são tão negativas. A maioria dos participantes classificam o seu sono como bom ou muito bom, quase metade dos participantes referiram dormir mais de 7 horas e a maioria apresentou uma eficiência de sono superior a 85%. De igual forma, 83,8% nunca usaram medicação para dormir. Não sendo um resultado robusto, torna-se imperioso a realização de mais estudos que o comprovem inequivocamente. Mais, tais estudos também serão imprescindíveis para identificar situações em que a intervenção terapêutica melhorará tais parâmetros.