Modelling of the mammalian auditory system is valuable in understanding perception processes and has benefits in the design of signal processing systems and human prosthetic implants. However, as models increase in complexity, traditional methods of modelling using general purpose computers become very slow. One method of overcoming this is to use electronic implementations of these models. This thesis looks into the feasibility of auditory system implementations in digital technology, through the implementation of the Four-Stage Pitch System for pitch detection in hearing proposed by Hewitt and Meddis.

Made available in DSpace on 2016-12-09T13:52:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-21. Added 1 bitstream(s) on 2016-12-09T13:55:26Z : No. of bitstreams: 1 000871652.pdf: 1546445 bytes, checksum: 6c24eaf8c9a2b44f459fe4d619b1df3d (MD5) / A precisão de adaptação entre componentes em implantodontia pode ser influenciada por muitos fatores, destacando-se as etapas clínicas e laboratoriais envolvidas durante a execução do tratamento. Com a finalidade de proporcionar uma reabilitação implantoprotética confiável, vários estudos têm sido desenvolvidos para produzir moldes com maior precisão. Para transferir o correto posicionamento do implante e manter a dimensão vertical original da oclusão em pacientes edêntulos, técnicas de moldagem têm sido utilizadas com guias multifuncionais (GM). Os Sistemas CAD/CAM atualmente são empregados para minimizar a imprecisão dimensional ao transferir a posição dos implantes ou pilares para os modelos de trabalho. Assim sendo, o objetivo do presente estudo foi avaliar a precisão de diferentes técnicas de moldagem usando GM por meio da análise de microscopia óptica (LEICA QWin - Leica Microsystems, Wetzar, Germany) e análise tridimensional 3D (scanner Lava Scan ST, 3M ESPE, St. Paul, USA). Para tanto, dois materiais de moldagem foram utilizados: silicone de adição (SA) e polieter (PL) e 5 diferentes técnicas de moldagem, (n=8): G0: modelo mestre; G1: transferentes quadrados sem união (SA + SU); G2: transferentes quadrados unidos com resina acrílica Pattern (SA+RP); G3: transferentes quadrados unidos com resina acrílica Pattern e união com resina acrílica ao GM (SA+ RP*+GM); G4: transferentes quadrados unidos com barras de metal (SA+ MET); G5: transferentes quadrados unidos com barras de metal e união com resina acrílica ao GM (SA+MET*); os mesmos métodos para o material (PL), grupos: G6: PL+SU; G7: PL+RP; G8: PL+RP*; G9:PL+MET; G10: PL+MET*. A análise tridimensional foi empregada apenas os grupos G0, G1, G2, G3, G4 E G5. O software Cumulus (Cumulus, Alpha Build Version 0.8; University of Minnesota, MN., USA) foi utilizado para sobrepor as imagens examinadas... (Resumo completo, clicar acesso eletrônico abaixo) / The accuracy fit among implant components can be influenced by several factors, especially laboratory and clinical protocols evolved during the treatment. In order to provide a more reliable implant-prosthetic rehabilitation, several studies have been developed recently to produce casts with higher accuracy. To transfer a correct implant position, and to maintain the original vertical dimension of occlusion (DVO) for the edentulous patients, impression techniques have been used with Multifunctional Templates (MT). The systems (CAD/CAM) have been used to minimize dimensional inaccuracy when transferring the position of the implant fixtures or abutments to working casts. Therefore, the aim of the present study is to compare the accuracy of different techniques using MT by analyzing with optical microscopie ((LEICA QWin - Leica Microsystems, Wetzar, Germany ) and 3D digital images.(scanner Lava Scan ST, 3M ESPE, St. Paul, USA) Methods: Five impression techniques, (n=8 for each technique, with polyvinyl siloxane (SA) (3M/ESPE, Califórnia, USA) and polyeter (PL) were studied; G0: master model, G1: MT with squared non-splinted copings (SA+SU) G2: ST with squared copings splinted with acrylic resin (SA+RP); ; G3: MT with squared coings splinted with acrylic resin and then the acrylic resin were splinted to MT (SA+RP*); G4: MT with squared copings splinted with metal bars (SA+MET); G5: MT with squared copings splinted with metal bars that were splinted to MT with acrylic resin (SA+MET*), and the groups (PL): G6: (PL+SU); G7: (PL+RP); G8: (PL+RP*); G9: (PL+MET); G10: (PL+MET*).. The 3Danalysiswasappliedto: G0, G1, G2, G3, G4 and G5. The software Cumulus (Minnesota Dental Research Center for Biomaterials and Biomechanics, MN, USA) was used to superimpose the cast images scanned by Lava Scan ST (3M ESPE) to calculate the 3-dimensional distances of the spatial discrepancy. The data sowed for ...(Complete abstract electronic access below)

Orientador: Francisco de Assis Molle Junior / Banca: João Neudenir Arioli Filho / Banca: Luis Geraldo Vaz / Banca: Mauro Antonio de Arruda Nóbilo / Banca: Pedro Cesar Garcia de Oliveira / Resumo: A precisão de adaptação entre componentes em implantodontia pode ser influenciada por muitos fatores, destacando-se as etapas clínicas e laboratoriais envolvidas durante a execução do tratamento. Com a finalidade de proporcionar uma reabilitação implantoprotética confiável, vários estudos têm sido desenvolvidos para produzir moldes com maior precisão. Para transferir o correto posicionamento do implante e manter a dimensão vertical original da oclusão em pacientes edêntulos, técnicas de moldagem têm sido utilizadas com guias multifuncionais (GM). Os Sistemas CAD/CAM atualmente são empregados para minimizar a imprecisão dimensional ao transferir a posição dos implantes ou pilares para os modelos de trabalho. Assim sendo, o objetivo do presente estudo foi avaliar a precisão de diferentes técnicas de moldagem usando GM por meio da análise de microscopia óptica (LEICA QWin - Leica Microsystems, Wetzar, Germany) e análise tridimensional 3D (scanner Lava Scan ST, 3M ESPE, St. Paul, USA). Para tanto, dois materiais de moldagem foram utilizados: silicone de adição (SA) e polieter (PL) e 5 diferentes técnicas de moldagem, (n=8): G0: modelo mestre; G1: transferentes quadrados sem união (SA + SU); G2: transferentes quadrados unidos com resina acrílica Pattern (SA+RP); G3: transferentes quadrados unidos com resina acrílica Pattern e união com resina acrílica ao GM (SA+ RP*+GM); G4: transferentes quadrados unidos com barras de metal (SA+ MET); G5: transferentes quadrados unidos com barras de metal e união com resina acrílica ao GM (SA+MET*); os mesmos métodos para o material (PL), grupos: G6: PL+SU; G7: PL+RP; G8: PL+RP*; G9:PL+MET; G10: PL+MET*. A análise tridimensional foi empregada apenas os grupos G0, G1, G2, G3, G4 E G5. O software Cumulus (Cumulus, Alpha Build Version 0.8; University of Minnesota, MN., USA) foi utilizado para sobrepor as imagens examinadas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The accuracy fit among implant components can be influenced by several factors, especially laboratory and clinical protocols evolved during the treatment. In order to provide a more reliable implant-prosthetic rehabilitation, several studies have been developed recently to produce casts with higher accuracy. To transfer a correct implant position, and to maintain the original vertical dimension of occlusion (DVO) for the edentulous patients, impression techniques have been used with Multifunctional Templates (MT). The systems (CAD/CAM) have been used to minimize dimensional inaccuracy when transferring the position of the implant fixtures or abutments to working casts. Therefore, the aim of the present study is to compare the accuracy of different techniques using MT by analyzing with optical microscopie ((LEICA QWin - Leica Microsystems, Wetzar, Germany ) and 3D digital images.(scanner Lava Scan ST, 3M ESPE, St. Paul, USA) Methods: Five impression techniques, (n=8 for each technique, with polyvinyl siloxane (SA) (3M/ESPE, Califórnia, USA) and polyeter (PL) were studied; G0: master model, G1: MT with squared non-splinted copings (SA+SU) G2: ST with squared copings splinted with acrylic resin (SA+RP); ; G3: MT with squared coings splinted with acrylic resin and then the acrylic resin were splinted to MT (SA+RP*); G4: MT with squared copings splinted with metal bars (SA+MET); G5: MT with squared copings splinted with metal bars that were splinted to MT with acrylic resin (SA+MET*), and the groups (PL): G6: (PL+SU); G7: (PL+RP); G8: (PL+RP*); G9: (PL+MET); G10: (PL+MET*).. The 3Danalysiswasappliedto: G0, G1, G2, G3, G4 and G5. The software Cumulus (Minnesota Dental Research Center for Biomaterials and Biomechanics, MN, USA) was used to superimpose the cast images scanned by Lava Scan ST (3M ESPE) to calculate the 3-dimensional distances of the spatial discrepancy. The data sowed for ...(Complete abstract electronic access below) / Doutor

Biomedical devices that function in-vivo offer a tremendous promise to improve the quality of life for many who suffer from disease and trauma. The most important consideration for these devices is that they interact with the physiological environment as designed without initiating a deleterious inflammatory response. ISO 10993 outlines the current international guideline for investigating the biocompatibility of such devices. Numerous groups report the use of ISO 10993 as the basis for their experimental evaluation of candidate materials for neuroprosthetics, as well as other biomedical devices, however most of these reports fail to completely comply with the standard. This leads to a lack of consistent results between R&D groups, which hinders progress in the implantable biomedical device field. For the first time, and to the best of our knowledge, we present a methodology that is in strict adherence to the methodologies presented in ISO 10993, namely direct contact and extract testing. In addition we show that the MTT assay, which has been used in multiple reports, suffers from a major flaw that can create false results especially for conductive materials. We also report on our application of ISO 10993-12 with respect to control materials and preparation methods. These materials are gold and polyethylene as negative reaction controls, and copper and polyvinyl chloride organotin (PVC-org. Sn) as positive reaction controls. The results of our tests are consistent to what has been previously reported, albeit in separate reports. We used silicon carbide, which is a very promising candidate material for neuroprosthetics, as our test materials. Not only have we confirmed the outstanding in-vitro response of 3C-SiC and amorphous SiC, we do this in strict compliance to ISO 10993 thus showing that it is indeed possible to quantitatively assess the performed of materials in a statistically significant and highly repeatable fashion.