97 research outputs found
Refracción virtual con diferentes perfiles aberrométricos
A partir de perfiles aberrométricos, se modifican las aberraciones de bajo orden con el objetivo de generar diferentes ametropÃas. Mediante el simulador de refracción subjetiva virtual, se han comparado los resultados de refracción subjetiva virtual encontrados con dos métodos refractivos diferentes. El primer método determina el astigmatismo con el test de los CCJ y el segundo método determina el astigmatismo con el test de la esfera horaria. <br /
Integrated optical bimodal waveguide biosensors : principles and applications
Altres ajuts: the ICN2 is funded by the CERCA program/Generalitat de Catalunya.Integrated optical biosensors have become one of the most compelling technologies for the achievement of highly sensitive, multianalyte, portable and easy to use point-of-care (POC) devices with tremendous impact in healthcare and environmental protection, among other application fields. In this context, bimodal waveguide (BiMW) interferometers have emerged over the last years as a powerful biosensor technology providing the benefits of extreme sensitivity under a label-free scheme, reliability and robustness within a highly compact footprint that can be integrated and multiplexed in lab-on-a-chip (LOC) platforms. In this review, we provide an overview of the state-of-the-art about integrated optical BiMW biosensors from the theoretical fundamentals to their practical implementation. Furthermore, we explore recent advances such as novel designs, integration in specific LOC systems and its application in real biosensing scenarios. Final remarks and perspectives on the potential impact of these biosensor interferometric structures are also provided, as well as some limitations that must be addressed in next steps
Treball de selecció de materials
L’objectiu principal de l’activitat és desenvolupar l’aprenentatge autònom mitjançant el
desenvolupament d’un treball en grup relacionat amb l’à mbit dels materials
Surface competition between osteoblasts and bacteria on silver-doped bioactive titanium implant
The rapid integration in the bone tissue and the prevention of bacterial infection are key for the success of the implant. In this regard, a silver (Ag)-doped thermochemical treatment that generate an Ag-doped calcium titanate layer on titanium (Ti) implants was previously developed by our group to improve the bone-bonding ability and provide antibacterial activity. In the present study, the biological and antibacterial potential of this coating has been further studied. In order to prove that the Ag-doped layer has an antibacterial effect with no detrimental effect on the bone cells, the behavior of osteoblast-like cells in terms of cell adhesion, morphology, proliferation and differentiation was evaluated, and the biofilm inhibition capacity was assessed. Moreover, the competition by the surface between cell and bacteria was carried out in two different co-culture methods. Finally, the treatment was applied to porous Ti implants to study in vivo osteointegration. The results show that the incorporation of Ag inhibits the biofilm formation and has no effect on the performance of osteoblast-like cells. Therefore, it can be concluded that the Ag-doped surface is capable of preventing bone bacterial infection and providing suitable osseointegration.Postprint (published version
Resolución de problemas de materiales como herramienta de aprendizaje autónomo
El principal objetivo de la actividad es proporcionar herramientas al alumnado para consolidar los
conocimientos teóricos adquiridos en el ámbito de los materiales, mediante aprendizaje autónomo
basado en la resolución de ejercicios prácticos
Bateries de qüestions bà siques de materials
Fomentar l’estudi i l’aprenentatge autònom de continguts bà sics de les assignatures troncals de materials (Fonaments de Ciència dels Materials, Tecnologia dels Materials i Materials Aeroespacials), de les titulacions d’Enginyeria Industrial i Enginyeria Aeronà utica
Teaching composite materials using technology
La tecnologia de materials compostos combina un conjunt de processos i
materials complexos. S’ha dissenyat una prà ctica amb l’objectiu de transmetre
a l’alumne els conceptes de disseny i fabricació utilitzant les tècniques de la
infusió i el pre-impregnat; una prà ctica d’anà lisi i simulació computacional amb
validació experimental a partir d’un assaig destructiu de flexió i un no-destructiu
amb ultrasons i, finalment, s’ha proposat la presentació oral d’un treball davant
un grup d’alumnes.Peer Reviewe
El Joc de rol com a eina d’aprenentatge en assignatures de ciència i tecnologia de materials
La incorporació de les universitats europees a l'EHEA ha conduit a la remodelació de plans d'estudi i també, a la redefinició de protagonismes en el procés d'ensenyament-aprenentatge en l'à mbit universitari. AixÃ, el paradigma de Bolònia ha contribuït a que, progressivament, s'hagin incorporat competències, processos d'avaluació continuada, d'autoavaluació i de coavaluació, que afavoreixen que l'estudiantat formi part del propi procés d'aprenentatge. Paral•lelament, en els darrers anys, la diversitat de formats disponibles per compartir informació (text, imatge, simulacions, vÃdeo) ha ajudat a que la prà ctica docent pugui ser més à gil i, per tant, ha contribuït a afavorir la participació de l'estudiantat. En l'à mbit de materials, les tecnologies de comunicació han ajudat a visualitzar processos, a gestionar bases de dades de selecció de materials i a optimitzar les quotes d'atenció en l'activitat docent università ria.
En aquest escenari, el projecte RIMA (Recerca i Innovació en Metodologies d'aprenentatge) neix amb la voluntat de potenciar les activitats desenvolupades pels Grups d'Interès (Communities of Practice) que s'han creat a la UPC. Entre ells, el grup d'Innovació Docent en Materials, GidMAT, proporciona un espai de comunió i compartició d'experiències aixà com un foro de debat entre professionals de la docència de materials.
En aquest treball es proposa una activitat de joc de rol com a activitat prà ctica de materials en l'à mbit de l'enginyeria. La interacció professorat-alumnat és imprescindible i la metodologia proposada garanteix una constant comunicació i un feed-back eficaç que possibiliti l'avaluació continua de les assignatures de tecnologia de materials.Peer Reviewe
Development of novel dual-action coatings with osteoinductive and antibacterial properties for 3D-printed titanium implants
Gallium (Ga) has been recently proposed as a novel therapeutic agent, since it promotes bone formation and exhibits antibacterial properties. This work focuses on the optimization of a thermochemical treatment that incorporates Ga ions by the addition of the body-friendly Ga nitrate approved by the Food and Drug Administration. The objective was to simultaneously provide the inner and the outer surfaces of porous-titanium surfaces obtained by 3D-printing with bioactivity and antibacterial properties. The apatite-forming ability of the coating, as well as the antibacterial activity and SaOS-2 cell adhesion, proliferation, differentiation and mineralization were evaluated and compared with untreated Ti surfaces. The characterization of the surfaces revealed the presence of a Ga-containing calcium titanate layer, which was non cytotoxic and in simulated body fluid produced a homogeneous apatite coating well adhered to the substrate. The formation of this apatite layer was accelerated with increasing Ga amounts present on the surface, resulting also in an increase in thickness. An initial quick release of Ga ion promoted the antibacterial effect against gram positive strains, especially for Pseudomonas aeruginosa, one of the most frequent resistant pathogens in nosocomial infections. SaOS-2 cells adhered and proliferated on the Ga-doped Ti surfaces, its presence contributed to cell differentiation and to considerably increase the mineralization levels. Thus, the developed multifunctional coatings could provide bioactivity to the porous Ti implants while protecting them from the most frequent gram-negative pathogens.Peer ReviewedPostprint (author's final draft
Multifunctional homogeneous calcium phosphate coatings: Toward antibacterial and cell adhesive titanium scaffolds
Implants for orthopedic applications need to be biocompatible and bioactive, with mechanical properties similar to those of surrounding natural bone. Given this scenario titanium (Ti) scaffolds obtained by Direct Ink Writing technique offer the opportunity to manufacture customized structures with controlled porosity and mechanical properties. Considering that 3D Ti scaffolds have a significant surface area, it is necessary to develop strategies against the initial bacterial adhesion in order to prevent infection in the early stages of the implantation, while promoting cell adhesion to the scaffold. The challenge is not only achieving a balance between antibacterial activity and osseointegration, it is also to develop a homogeneous coating on the inner and outer surface of the scaffold. The purpose of this work was the development of a single-step electrodeposition process in order to uniformly cover Ti scaffolds with a layer of calcium phosphate (CaP) loaded with chlorhexidine digluconate (CHX). Scaffold characterization was assessed by scanning electron microscopy, Energy dispersive X-ray spectroscopy, X-ray diffraction, micro-Raman microscopy and compressive strength tests. Results determined that the surface of scaffolds was covered by plate-like and whisker-like calcium phosphate crystals, which main phases were octacalcium phosphate and brushite. Biological tests showed that the as-coated scaffolds reduced bacteria adhesion (73 ± 3% for Staphylococcus aureus and 70 ± 2% for Escherichia coli). In vitro cell studies and confocal analysis revealed the adhesion and spreading of osteoblast-like SaOS-2 on coated surfaces. Therefore, the proposed strategy can be a potential candidate in bone replacing surgeries
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