Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
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- Technological development of Alginate/Gelatin composite hydrogel fabricated by microextrusion based printing for tissue regeneration(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2018-05-14) Urruela Barrios, Rodrigo Alejandro; Ortega Lara, Wendy de Lourdes; Alvarez Guerra, Alejandro; Vázquez Lepe, Elisa Vrginia; García López, ErikaAlginate hydrogels have shown an enormous potential for tissue engineering due to its non-toxicity, biocompatibility, and structural similarity to extracellular matrices. To produce these hydrogels, different manufacturing techniques can be used, including microextrusion 3D printing. Current efforts for hydrogels in tissue engineering are centered on improving bioactivity and mechanical properties by the incorporation of a second biopolymer or bioceramics; and loading these materials with pharmaceutical drugs to promote a better healing process. In this work, the study of the synthesis process of alginate/gelatin hydrogels reinforced with TiO2 and beta-tricalcium phosphate (beta-TCP) and loaded with ibuprofen, its extrusion in a modified 3D Printer, and its material characterization were proposed. The hydrogel systems were successfully micro-extruded by tuning the concentration of the pre-crosslinking agent up to 0.20 w/v% and a rheological profile was obtained. FT-IR, XRD, and TGA were used to perform a physicochemical characterization and prove the growth of ibuprofen crystals inside the porous material. For the drug loading, stable microemulsions were obtained with polyvinyl alcohol (PVA) as emulsifier and various solvents, including dichloromethane. The pores of the crosslinked printed structures were measured using SEM and resulted in an average pore size from 160 μm to 40 μm, depending on the material composition, all with adequate porosity for tissue engineering. Furthermore, the hydrogels reinforced with TiO2 and beta-TCP showed enhanced mechanical properties up to 65 MPa of elastic modulus. Controllable drug loading was achieved up to 35 w/w% of the dry hydrogel with more than 50% of the loaded ibuprofen dissolving in less than one hour. Additionally, while the hydrogel was microextruded in the 3D printer, it was found that as more layers of the design were deposited in the built platform, there was an increase of the line width of the bottom layers due to its viscous deformation. Shrinkage of the design when the hydrogel is crosslinked and later freeze-dried was also measured and found to be up to 27% from the printed design. Overall, the approach taken enables to synthesize a printable composite alginate solution, loaded with an API, with adequate physical properties for tissue regeneration.
- Definition of bio-physics framework for advanced driver assistance systems’ design and development(2017-12-05) Ledezma-Zavala, Edgar; Ramírez Mendoza, Ricardo; Bustamante-Bello, Rogelio; Soto Rodríguez, RogelioMost recent efforts made in the industry to the path for a full autonomous vehicle have been focusing on the automation of the vehicles’ maneuvers, and the understanding of the surroundings. While a great advance has been achieved, the most advanced implementations of such systems may be only at the scale defined by the US National Highway Traffic Safety Administration as a level 2: “automation of at least two primary control functions”. Such systems require the driver to keep their hands on the steering wheel at all the time. One popular example for this is Tesla Motors´ “Autopilot” feature, which is in fact just a diver-assistant feature rather than a fully autonomous driving system. Given an NHTSA level 2 can still drive on itself by hundreds of miles in the highway, it is easy for driver to misinterpret the real capabilities of current systems and get comfortable on letting the machine take its decisions alone, wandering around visually or mentally, believing they are using a “limited self-diving” NHTSA level 3 of automation, or even a fully autonomous level 4. Current systems have evolved to process a great amount of information coming from the environment, but they may be leaving out the most important character involved in the vehicle: the driver. This project focuses on that forgotten element in the vehicle framework and intends to stablish a robust yet flexible representation for such a concept system as a driving environment, considering the driver itself, the internal mechanics of the vehicle, and external elements such as the driveway, other vehicles or pedestrians and traffic signals both passive and possible active signals with intelligent capabilities of Intelligent Transportations Systems (ITS)
- Desing of a deterministic closed-loop supply chain model for a product, with returns in the same period and following period(2017-12-04) Aguilera Garza, Héctor Eloy; González Velarde, José Luis; Zavila Río, Daniel; Sánchez García, José ManuelThe following work presents the study of a closed-loop supply chain problem, considering a single product with returns in the same period and in a subsequent period, considering only a deterministic model. The paper proposes a mixed integer mathematical model, which considers strategic and operational decisions, aimed at minimizing the expected total annual costs of the network considering different types of costs such as infrastructure costs, variable costs and operating profits. A computational experiment is presented in which the model is analyzed, the rate of return and recovery and the rescue value, and compared with another model created where the returns are only made within the same period.
- Development of methodological process to customize and manufacture cranial implants with high density polyethylene by means of Single Point Incremental Forming(2017-04) Salas Luna, Eduardo; Martínez Romero, Oscar; Perales Martínez. Imperio Anel; Zuñiga, Alex Elías; Caro Osorio, EnriqueThe aim of the present thesis is to evaluate the feasibility of manufacturing customized cranial implants applying the Single Point Incremental Forming (SPIF) technique on a bio compatible polymer such as High Density Poly Ethylene (HDPE). The following research focuses on a CAD/CAM aided process that will help to find the optimal parameters to secure the best precision of the manufactured piece. This technique offers a sustainable, cheap and highly accurate process that will allow a bigger number of patients the possibility to have access to a high quality, aesthetic prosthesis that will improve their life quality