Browsing by Author "Bártolo, Paulo"
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- Biopolymer-based manufacturing system for medical applicationsPublication . Lagoa, Ricardo; Bártolo, Paulo; Mendes, Ausenda
- Development of novel alginate based hydrogel films for wound healing applicationsPublication . Pereira, Rúben; Carvalho, Anabela; Vaz, Daniela C.; Gil, M. H.; Mendes, Ausenda; Bártolo, PauloAlginate and Aloe vera are natural materials widely investigated and used in the biomedical field. In this research work, thin hydrogel films composed by alginate and Aloe vera gel in different proportions (95:5, 85:15 and 75:25, v/v) were prepared and characterized. The films were evaluated regarding the light transmission behavior, contact angle measurements, and chemical, thermal and mechanical properties. These thin hydrogel films, prepared by crosslinking reaction using 5% calcium chloride solution, were also investigated relatively to their water solubility and swelling behavior. Results showed that Aloe vera improved the transparency of the films, as well their thermal stability. The developed films present adequate mechanical properties for skin applications, while the solubility studies demonstrated the insolubility of the films after 24 h of immersion in distilled water. The water absorption and swelling behavior of these films were greatly improved by the increase in Aloe vera proportion.
- EditorialPublication . Bártolo, Paulo; Chua, C. K.In this issue, we invited five winners of the ‘Best Paper Awards’ at the 4th International Conference on Advanced Research in Virtual and Rapid Prototyping, Leiria, Portugal, 6-10 October 2009, to enhance their conference papers to the standard of an international journal. One paper each from ‘Materials’ track, ‘Biomanufacturing’ track and ‘Virtual Environment & Simulation’ track and two papers from ‘Advanced Rapid Prototyping Technologies and Nanofabrication’ track.
- EditorialPublication . Bártolo, Paulo; Chua, C. K.As time goes on, the relevance of the Virtual and Physical Prototyping journal increases. This Journal was submitted to Thomson Scientific to be accepted as an ISI Journal and the number of conferences asking for our endorsement is growing fast, such as the following: . International Conference on Additive Technologies, IC AT2010, 22 24 September 2010, Nova Gorica, Slovenia . Virtual Concept 2010, 20-22 October 2010, Bordeaux, France Both conferences will be endorsed by Virtual and Physical Prototyping, as will the 5th International Conference on Advanced Research in Virtual and Rapid Prototyping (VRAP Conference), which will be held at Leiria by the Centre for Rapid and Sustainable Product Development of the Polytechnic Institute of Leiria, from 28 September to 1 October 2011.
- EditorialPublication . Bártolo, Paulo; Chua, C.K.The year of 2012 is a fruitful year for Virtual & Physical Prototyping. The journal has maintained its usual publication record and published a total of twenty-three original research articles (including this issue). Similarly, total citations to this journal in Year 2012 have also maintained at a near-hundred level by the mid-October (Scopus). The stabilized publication record and total citations demonstrate a mature and healthy status of the journal. In this regard, we thank all authors who have made contributions to this journal.
- EditorialPublication . Bártolo, Paulo; C. K. Chua
- Monitoring the modifications of Aloe vera by high performance liquid chromatographyPublication . Tojeira, Ana; Pereira, Rúben; Bártolo, Paulo; Mendes, Ausenda; Vaz, Daniela; Oliveira, Nelson SimõesAloe vera is a widely known and studied plant due to its therapeutic properties. The therapeutic properties exhibited by the Aloe vera exudates have been associated to the presence of certain compounds, such as, chromones, anthrones and anthraquinones. In this study, we have identified, and monitored by reversed phase high performance liquid chromatography (HPLC), six major compounds present in the Aloe vera exudates. The chromatographic profiles were followed in the course of time and at different wavelengths. This monitoring allowed us to verify the constitution and modifications of the samples, in order to identify the main changes responsible for the chemical degradation and loss of proprieties exhibited by the exudates over time.
- Moving Forward to 3D/4D Printed Building FacadesPublication . Craveiro, Flávio; Duarte, José P.; Bártolo, Helena; Bártolo, PauloNearly Zero Energy Buildings will require high-performance building envelopes, though the building sector is currently a major contributor to the world’s energy consumption and related CO2 emissions. Innovative advanced materials, such as smart or functionally graded materials are being developed to better adapt buildings to environmental needs. This paper presents a brief overview of novel advanced materials for passive/kinetic facades. There is a great potential for 3D/4D printing building components to address actual and future built environmental challenges. 3D printing buildings are still in its infancy, several limitations and barriers need to be addressed, though architects and engineers must keep looking forward and the rise of 4D design could bring “life” to buildings.
- Optimization of Scaffolds in Alginate for Biofabrication by Genetic AlgorithmsPublication . Rezende, Rodrigo; Rezende, Mylene; Bártolo, Paulo; Mendes, Ausenda; Filho, Rubens Maciel; Bartolo, Paulo; Mendes, AusendaWith an increasing in the rate of transplants due to damaged or affected tissues or organs by accidents or diseases and also by the aging of the population in many countries as Brazil, have motivated the research of some novel and alternative ways focused on restoring and replacing tissues. Biofabrication by means of Rapid Prototyping techniques can help in the fashioning and final production of scaffolds devoted to support and stimulate the growth of new tissues. For soft tissues, a biomaterial known as Alginate has been studied and used as raw-material for scaffolds fabrication. A scaffold must guarantee good strength and stiffness at the same time the material degrades gradually. In this work, a single mathematical model experimentally obtained that describes an interesting mechanical behavior of the degradation of alginated-scaffolds is developed. The optimization process scheme using Genetic Algorithms to maximize the elastic modulus and therefore to aid the design of scaffolds in alginate is proposed. The optimization is very welcome to tissue engineering and Biofabrication.
- Structural optimisation for medical implants through additive manufacturingPublication . Al-Tamimi, Abdulsalam Abdulaziz; Almeida, Henrique; Bártolo, PauloAdvanced manufacturing techniques are being explored to fabricate degradable and non-degradable, porous or non-porous implants for medical applications. These implants have been designed using standard computer-aided design (CAD) and computer-aided engineering (CAE) tools and produced in a multitude of materials. The recent use of optimisation tech niques, mainly topology optimisation, allows the development of additive manufactured medical devices with improved performance. This review discusses the combined use of optimisation techniques and additive manufacturing to produce biocompatible and biodegradable scafolds for tissue engineering with improved mechanical and permeability properties; metallic lattice structures with reduced weight and minimal stress shielding efect; and lightweight personalised orthopae dic implants. Three optimisation routes are considered: topology optimisation; triply periodic minimal surfaces that can be manipulated by means of the equations parameters to optimise the overall performance; and the use of repetitive structures that are optimised as unit cells under certain conditions to compose a bulk object. Major limitations and research challenges are highlighted and discussed.