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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Determining Barriers and Facilitators to Implementing the Resist Diabetes Intervention in Salem Veterans Administration Medical Center Patients

VanDerBrink, Emily Marie 19 July 2019 (has links)
With 47% of the veteran population aged 65 years or older, an age group with the highest prevalence of type 2 diabetes (T2D), prevention of T2D is critical within the Veterans Health Administration (VHA) system (1). Resist Diabetes (RD), a Social Cognitive Theory-based resistance training program, has been shown to reduce the prevalence of prediabetes by 34% in prediabetic older adults (2). The RD program could fill the gap within the VHA system for a structured diabetes prevention program not focused on weight, but instead focused on exercise. This thesis describes a mixed-methods investigation to determine what adaptations to the RD program are needed to implement the program within the Salem Veterans Affairs Medical Center (VAMC) patients. Salem VAMC care providers and veteran patients were recruited to gauge perceptions of the RD program, and identify barriers and facilitators to the referral process and program implementation. Semi-structured open-ended questionnaires and interview guides based upon the Consolidated Framework for Implementation Research (CFIR) (3) were utilized to determine major and minor themes within the provider and veteran responses. Quantitative data was also obtained to assess provider perceptions and participant characteristics. Major findings included: positive perceptions by providers for RD program acceptability, appropriateness and feasibility (4) within the Salem VAMC, positive perceptions of Intervention Characteristics of RD by veterans, major barriers to participation lied within the Outer Setting domain with travel, transportation, and time constraints. Major facilitators to program implementation lied within the Inner Setting domain with promotion by primary care. These findings could be used to inform a future version of the RD program adapted for the VHA system. / Master of Science / With 47% of the veteran population aged 65 years or older, an age group with the highest prevalence of type 2 diabetes (T2D), prevention of T2D is critical within the Veterans Health Administration (VHA) system. Resist Diabetes, a Social Cognitive Theory-based resistance training program, reduced the prevalence of prediabetes by 34% in prediabetic older adults in the Roanoke, VA area. This thesis describes a mixed-method investigation to determine what adaptations to the Resist Diabetes program are needed to implement the program within the Salem Virginia Veterans Affairs Medical Center.
2

Study of Non-Traditional Resist Materials and Techniques for Pattern Dyeing

Williams, Shirlee R. 08 1900 (has links)
Both the challenges and rewards of pattern dyeing motivated an examination of resist materials, the subject of this study. The first part of the problem was to investigate new materials and those not previously used for dye resists. The second part was to test some of the traditional resisting agents in non-traditional ways. The selected materials were evaluated for their effectiveness as dye resists and for their usefulness to the artist-craftsman. They were also compared to traditional techniques to determine any advantages they may or may not have over previous resist materials.
3

Development and Applications of Thin Film Resists for Electron Beam Lithography

Fairley, Kurtis 23 February 2016 (has links)
Throughout this work several thin film resists have been studied with substantial focus on HafSOx and SU-8. The study of HafSOx has granted more insight into how inorganic, spin coated films form and react under the electron beam. These films have been shown to form a thin dense crust at the surface that could have interesting implications in the interaction of the electrons. Continuing to further understand the electron interactions within the resist, low voltage patterns were created allowing the accelerating voltage to be matched to the film. With this general knowledge, higher resolution films can be constructed with shorter patterning times. Both resists complement each other in that HafSOx produces incredibly thin, dense structures to be formed with features below 10 nm in all dimensions. SU-8 allows micron thick features to be created over several millimeters. This flexibility in feature size enabled the creation of large fractals that could improve neuron binding to artificial retina down to the smallest fractals reported that are interesting for their applications as antennas. The final facet of this work involved looking at other methods of making structures. This was done through adding differing salts to organic molecules that stack into unique crystals. This dissertation includes previously published co-authored material.
4

Optical modeling and resist metrology for deep-UV photolithography

Liu, Chao 30 October 2006 (has links)
This thesis first presents a novel and highly accurate methodology for investigating the kinetics of photoacid diffusion and catalyzed-deprotection of positive-tone chemically amplified resists during post exposure bake (PEB) by in-situ monitoring the change of resist and capacitance (RC) of resist film during PEB. Deprotection converts the protecting group to volatile group, which changes the dielectric constant of resist. So the deprotection rate can be extracted from the change of capacitance. The photoacid diffusivity is extracted from the resistance change because diffusivity determines the rate of change of the acid distribution. Furthermore, by comparing the R and C curves, the dependence of acid diffusivity on reaction state can be extracted. The kinetics of non-Fickean acid transportation, deprotection, free volume generation and absorption/escaping, and resist shrinkage is analyzed and a comprehensive model is proposed that includes these chemical/physical mechanisms. Then in this thesis a novel lithographic technique, liquid immersion contact lithography (LICL) is proposed and the simulations are performed to illustrate its main features and advantages. Significant depth-of-field (DOF) enhancement can be achieved for large pitch gratings with deep-UV light (λ=248nm) illumination with both TM and TE polarizations by liquid immersion. Better than 100nm DOF can be achieved by when printing 70nm apertures. The simulation results show that it is very promising to apply this technique in scanning near field optical microscopy. Finally, a rigorous, full vector imaging model of non-ideal mask is developed and the simulation of the imaging of such a mask with 2D roughness is performed. Line edge roughness (LER) has been a major issue limiting the performance of sub-100nm photolithography. A lot of factors contribute to LER, including mask roughness, lens imperfection, resist chemistry, process variation, etc. To evaluate the effect of mask roughness on LER, a rigorous full vector model has been developed by the author. We calculate the electromagnetic (EM) field immediately after a rough mask by using TEMPEST and simulate the projected wafer image with SPLAT. The EM field and wafer image deviate from those from an ideal mask. LER is finally calculated based on the projected image.
5

Painted Shibori /

Kim, Soon-Hye. January 1988 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 1988. / Includes bibliographical references (leaf 24).
6

FOTOSSINTESE, CRESCIMENTO E COMPOSIÇÃO QUIMICA EM PLANTAS DE THEOBROMA CAÇAO L, SUBMETIDAS A DIFERENTES CONCENTRAÇÕES DE SILICATO DE POTASSIO E SUA INTERAÇÃO COM INSETOS-PRAGA

PINTO, D. G. 18 February 2011 (has links)
Made available in DSpace on 2018-08-02T00:16:22Z (GMT). No. of bitstreams: 1 tese_5185_DISSERTAÇÃO FINAL Diego G. Pinto.pdf: 623189 bytes, checksum: ce152bd197b4657ef0bb436a118311ff (MD5) Previous issue date: 2011-02-18 / RESUMO PINTO, Diego Guimarães. M.Sc. Universidade Federal do Espírito Santo. Fevereiro de 2011. Fotossíntese, crescimento e composição química em plantas de Theobroma cacao L. submetidas a diferentes concentrações de silicato de potássio e sua interação com insetos-praga. Marco Antonio Galeas Aguilar (Orientador); Diolina Moura Silva (Co-orientadora). O controle de insetos-praga mediante o uso de agroquímicos, ainda é o método mais utilizado no cultivo do cacau. No entanto, devido à questões ambientais, há necessidade de buscar novas alternativas de controle menos danosas ao ambiente e ao homem. Nesse contexto, o silício é um nutriente que está sendo utilizado em diversas culturas, devido a seus efeitos benéficos na fisiologia da planta e na proteção ao ataque de insetos-praga e de agentes causadores de doenças. O objetivo deste trabalho foi avaliar a fotossíntese, o crescimento e a composição química em três genótipos de cacau submetidos a diferentes concentrações de silicato de potássio e sua interação com insetos-praga. Foram realizados dois experimentos, sendo o primeiro instalado sob um sistema agroflorestal constituído por Bactris gasipaes e Theobroma cacao, no delineamento de blocos ao acaso, com quatro repetições, em arranjo fatorial 3 x 3, constituído de três genótipos (TSH 1188, CCN 51 e Catongo), três doses de silicato de potássio (0, 3 e 6 mL L-1) aplicadas via foliar. Foram realizadas avaliações do crescimento vegetativo; da cinética de emissão da fluorescência da clorofila a, dos teores de clorofila, da incidência e nível de dano provocado por insetos-praga, além dos teores foliares de silício. O crescimento vegetativo dos genótipos de cacau foi reduzido com a aplicação das doses de silicato de potássio, possivelmente em função da partição de assimilados que estariam sendo utilizados na biossíntese de compostos envolvidos na resistência da planta a insetos. O genótipo TSH 1188 apresentou maior incremento do crescimento vegetativo e massa seca quando comparado ao CCN 51 e Catongo, sendo o único genótipo que apresentou maior índice de clorofila e melhoria nos parâmetros de fluorescência da clorofila a quando aplicado 3 mL L-1 de silicato de potássio, principalmente no fluxo de energia do fotossistema II e nos índices de desempenho da planta para absorção (PIABS) e total (PITOTAL). A aplicação de silicato de potássio na dose 6 mL L-1 reduziu significativamente a incidência e o nível de dano provocado por insetos-praga nos genótipos de cacau. No entanto, não houve efeito significativo da aplicação de silicato de potássio sobre o teor de silício nas folhas dos genótipos de cacau estudados em relação ao controle. O segundo experimento foi instalado em casa de vegetação com os mesmos tratamentos e delineamento estatístico do experimento anterior. Nele foram avaliadas as trocas gasosas foliares, os teores foliares de fenóis solúveis totais; a fluorescência da clorofila a, além do teste de preferência com chance de livre escolha com pulgões. As maiores taxas fotossintéticas e condutância estomática foram encontradas no TSH 1188 e CCN 51. Estes mesmos genótipos apresentaram maiores índices de desempenho (PIABS e PITOTAL), resultado do aumento da densidade de centros de reação ativos do fotossistema II (RC/ABS), do rendimento quântico de FSII (φP0/(1- φP0)) e da eficiência das reações de oxi-redução além da quinona a- (ᴪ0/1-ᴪ0). A aplicação de silicato de potássio aumentou a fotossíntese líquida, mas não afetou os 8 índices de desempenho (PIABS e PITOTAL). Os teores de fenóis aumentaram nos genótipos CCN 51 e Catongo, já a preferência do pulgão foi reduzida com a aplicação de 6 mL L-1 de silicato de potássio apenas no TSH 1188. Em função dos resultados obtidos nos dois experimentos, a aplicação de silício é promissora no aumento da resistência do cacaueiro a insetos-praga, uma vez que promove o aumento da atividade fotossintética da planta e da produção de metabólitos envolvidos nos mecanismos de defesa do cacaueiro. Palavras-chave: silício, nutrição mineral, indução de resistência, fluorescência da clorofila a, compostos fenólicos, trocas gasosas.
7

Etiologia e perfil de resist?ncia de bact?rias isoladas de otite externa em c?es

Carvalho, Leonardo C?sar Andriola 19 May 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-15T11:56:11Z No. of bitstreams: 1 LeonardoCesarAndriolaCarvalho_DISSERT.pdf: 1817208 bytes, checksum: 513d53ff5b107ffefc3220ff658f24fa (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-16T16:04:39Z (GMT) No. of bitstreams: 1 LeonardoCesarAndriolaCarvalho_DISSERT.pdf: 1817208 bytes, checksum: 513d53ff5b107ffefc3220ff658f24fa (MD5) / Made available in DSpace on 2018-02-16T16:04:39Z (GMT). No. of bitstreams: 1 LeonardoCesarAndriolaCarvalho_DISSERT.pdf: 1817208 bytes, checksum: 513d53ff5b107ffefc3220ff658f24fa (MD5) Previous issue date: 2017-05-19 / A otite externa canina ? uma enfermidade relevante na cl?nica veterin?ria. Considerando a elevada frequ?ncia de atendimentos de c?es com otite externa bacteriana, objetivou-se identificar a frequ?ncia etiol?gica da otopatia e tra?ar o perfil de resist?ncia dos Staphylococcus Meticilina Resistentes (SMR) e enterobact?rias produtoras de Beta-Lactamases de Espectro Estendido (ESBL) em pacientes ambulatoriais e de internamento. As amostras foram submetidas a isolamento prim?rio, testes de susceptibilidade ? antimicrobianos e de resist?ncia bacteriana. Para os Staphylococcus sp. aplicou-se o Teste D (Disk Test) e o teste de Resist?ncia ? Meticilina (Met-25). Nas cepas positivas para o Met-25 foi feita Rea??o em Cadeia da Polimerase (PCR) para detec??o do gene mecA. Para estirpes positivas na PCR foi determinada a Concentra??o Bactericida M?nima (CBM) do gluconato de clorexidina. Os grupos bacterianos isolados das 140 amostras coletadas foram: Staphylococcus sp. (122 ? 49,38%), Pseudomonas sp. (22 ? 8,91%), enterobact?rias (19 ? 7,69%), Enterococcus sp. (17 ? 6,88%) e Acinetobacter sp. (12 ? 4,86%). Foram isoladas 14 cepas de SMR (11,47%) e todas continham o gene mecA. Observou-se que 14 Staphylococcus sp. foram Teste D positivo. Para os Staphylococcus coagulase positiva (SCP) a CBM foi de 500.000?g/mL (0,5%) enquanto que para os Staphylococcus coagulase negativa (SCN) o valor da CBM foi de 62.500?g/mL (0,0625%). Detectou-se 3 cepas de enterobact?rias ESBL. Os antimicrobianos mais efetivos para Staphylococcus sp. foram: Linezolida (100%), Rifampicina (94,26%) e Cloranfenicol (92,62%). Para Pseudomonas sp.: Cefepime (100%), Imipenem (100%) e Meropenem (100%). Para as enterobact?rias: Ertapenem (100%), Imipenem (100%) e Cefotaxima (84,21%). Para Enterococcus sp.: Cloranfenicol (100%), Linezolida (94,12%) e Vancomicina (88,24%). Para Acinetobacter sp.: Imipenem (100%), Meropenem (100%) e Ticarcilina com Clavulanato (91,67%). Apesar do gene mecA e de enterobact?rias produtoras de ESBL terem baixa ocorr?ncia neste estudo, existe a necessidade de um monitoramento constante em cepas isoladas de animais dom?sticos. Cultura bacteriol?gica e os testes de suscetibilidade aos agentes antimicrobianos s?o de grande import?ncia na rotina cl?nica veterin?ria para garantir o sucesso do tratamento de infec??es otol?gicas caninas. / The canine external otitis is a relevant disease regarding veterinary clinic. Considering the high frequency of treatment of dogs with external bacteria otitis, this research aims to identify the etiological frequency of otopathy and trace the resistance profile of the Methicillin Resistant Staphylococcus (MRS) and enterobacteria that produce Extended Spectrum Beta-Lactamase (ESBL) in outpatients and internment patients. The samples were submitted to primary isolation, tests of antimicrobial susceptibility and bacterial resistance. For the Staphylococcus sp. the Disk Test was applied along with the resistance test to Methicillin (Met-25). In the positive strains for Met-25, a Polimerase Chain Reaction (PCR) was applied to detect the mecA gene. For the PCR positive strains, a Minimum Bactericidal Concentration (MBC) of chlorhexidine gluconate was determined. The isolated bacterial groups of the 140 samples collected were: Staphylococcus sp. (122 ? 49.38%), Pseudomonas sp. (22 ? 8.91%), enterobacteria (19 ? 7.69%), Enterococcus sp. (17 ? 6.88%) and Acinetobacter sp. (12 ? 4.86%). 14 MRS strains (11.47%) were observed and all off them had the mecA gene. 14 Staphylococcus sp. were Disk Test positive. Concerning the positive Staphylococcus coagulase, the MBC was 500.00?g/mL (0.5%) whereas for the negative Staphylococcus coagulase the MBC value was 62.500?g/mL (0.0625%). 3 ESBL enterobacteria strains were detected. The more effective antimicrobial for the Staphylococcus sp. were: Linezolid (100%), Rifampicin (94.26%) and Chloramphenicol (92.62%). Regarding the Pseudomonas sp.: Cefepime (100%), Imipenem (100%) and Meropenem (100%). Regarding the enterobacteria: Ertapenem (100%), Imipenem (100%) and Cefotaxime (84.21%). Regarding the Enterococcus sp.: Chloramphenicol (100%), Linezolid (94.12%) and Vancomycin (88.24%). Regarding the Acinetobacter sp.: Imipenem (100%), Meropenem (100%) and Ticarcillin with Clavulanate (91.67%). Although the mecA gene and the enterobacteria that produce ESBL are briefly presented in this research, there is a need for constant monitoring of isolated strains in domestic animals. The bacteriological growth and the susceptibility tests in the antimicrobial agents are of great importance in the veterinary clinic routine in order to insure the success in treating canine otological infections.
8

Improving imaging performance in planar superlenses

Schøler, Mikkel January 2011 (has links)
The aim of this project was to improve the imaging performance of planar superlenses for evanescent near-field lithography. An experimental investigation of the performance of superlenses with reduced surface roughness was proposed. Such an investigation poses significant requirements in regards to process control in thin film deposition of silver onto dielectric substrates. Thin film deposition of silver films, onto silicon dioxide substrates, achieved films with root mean square surface roughness as low as 0.8 nm. While these experiments provided good understanding of the deposition process, significant variability of the surface roughness parameter remained an issue. The diffculty of achieving consistent control of surface roughness led to a finite element method simulation study where this parameter could be readily controlled. An improved understanding of how surface roughness affects superlens imaging performance was obtained from the results of this investigation. Furthermore, it was shown that in order to conduct an experimental investigation to verify the simulation results, it would be necessary to improve the imaging capability of super-resolution lithography protocols to achieve 3σ line edge roughness (LER) of <20 nm. Resist-scheme optimisation was identied as an important factor in this regard. Thus, a novel calixarene-based photoresist was formulated and characterised. The resist demonstrated superior imaging capabilities through interference lithography and evanescent near-field optical lithography, capable of resolving 250-nm period half-pitch line gratings with 3σ LER below 10 nm. The development of this novel photoresist will enable future lithographical investigations to be conducted with improved resolution and imaging fidelity.
9

Parafuso prot?tico de reabilita??es dent?rias sobre implantes :estudo mec?nico e an?lise pelo m?todo de elementos finitos

Barbosa, Gustavo Frainer 17 March 2006 (has links)
Made available in DSpace on 2015-04-14T13:58:37Z (GMT). No. of bitstreams: 1 346986.pdf: 3178845 bytes, checksum: 85423caf5393f07801ed0d94b0ba85c8 (MD5) Previous issue date: 2006-03-17 / O presente trabalho teve como objetivo desenvolver estudos mec?nicos sobre o parafuso prot?tico de reabilita??es dent?rias sobre implantes. Isto porque, este componente restaurador tem apresentado um n?mero expressivo de falhas, afrouxamento e/ou fratura, em especial os parafusos prot?ticos de uma empresa nacional com amplo alcance no mercado, a Conex?o Sistemas de Pr?tese?. Para que fosse atingido um resultado fidedigno e satisfat?rio, o trabalho foi dividido em duas etapas distintas. Numa primeira etapa, ap?s um amplo levantamento de informa??es mec?nicas e biomec?nicas que envolvem o complexo coroa, pilar, cilindro e parafuso prot?ticos, um programa em forma de planilha do Excel foi desenvolvido para que uma an?lise da especifica??o do torque recomendado pelo fabricante pudesse ser efetuada. Al?m disto, pode-se confirmar quais s?o as caracter?sticas mec?nicas necess?rias que devem estar presentes no parafuso prot?tico para que se possa desenvolver um determinado torque. Na segunda etapa proposta neste trabalho, foi utilizado um programa de an?lise por elementos finitos para verificar os locais onde ocorrem concentra??es de tens?o no parafuso prot?tico. Para isto todo o complexo prot?tico implantar foi constru?do e submetido ao teste de for?a, reproduzindo, assim, o mais pr?ximo poss?vel a realidade encontrada in vivo durante a aplica??o de for?as mastigat?rias. Os resultados obtidos na primeira etapa do trabalho demonstraram que o torque recomendado pelo fabricante est? dentro das reais necessidades do conjugado. E que a qualidade deste torque est? relacionada ao processo de fabrica??o do parafuso, como tamb?m, ao seu coeficiente de atrito. Na segunda etapa foi verificado que as ?reas onde ocorre maior concentra??o de tens?o est?o localizadas na uni?o entre a haste e a cabe?a do parafuso. Este ponto favorece o aparecimento de trincas que levar?o a fratura do material. Portanto, as solu??es propostas para o problema, dentro das limita??es deste trabalho, s?o uma adequa??o do processo de fabrica??o, como tamb?m uma pequena mudan?a no design do parafuso prot?tico de reabilita??es dent?rias sobre implantes osseointegrados. Isto feito, se estar? indo ao encontro da busca di?ria dos pacientes e dos profissionais reabilitadores, ou seja, da excel?ncia nos tratamentos propostos e realizados.
10

Efeito da espessura e do material restaurador na resist?ncia ? fratura de facetas oclusais confeccionadas em CAD/CAM

Andrade, Jonas Pereira 19 January 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-26T14:49:22Z No. of bitstreams: 1 DIS_JONAS_PEREIRA_ANDRADE_PARCIAL.pdf: 141765 bytes, checksum: 99338991681873f9d3d7028d9e7cdfa9 (MD5) / Made available in DSpace on 2017-06-26T14:49:22Z (GMT). No. of bitstreams: 1 DIS_JONAS_PEREIRA_ANDRADE_PARCIAL.pdf: 141765 bytes, checksum: 99338991681873f9d3d7028d9e7cdfa9 (MD5) Previous issue date: 2017-01-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The aim of the study was to evaluate, in vitro, the fracture resistance of occlusal veneers, made by CAD/CAM, with Lava Ultimate, e.max CAD and Vita Enamic materials in thicknesses of 0.6 mm and 1.5 mm. Seventy third human sound molars were randomly divided into seven groups (n = 10) according to the variables material and thickness, with the sound teeth as control. The root of the teeth was embedded into a self-cured acrylic resin and the teeth were prepared to simulate advanced erosion of the occlusal surface. The occlusal veneers were made using CAD-CAM technology, being luted to the preparation with adhesive systems and resin cements. After storage in distilled water at 37 ?C for 24 h, the samples were submitted to mechanical cyclic loading (1 million cycles at 100 N load). Subsequently, the sound teeth and the samples with the occlusal veneers were submitted to the fracture resistance test in a universal testing machine with crosshead speed of 1 mm/min. The failures were classified as reparable and irreparable. According to two-way ANOVA, the interaction between material and thickness was significant (p=0.013). The highest fracture resistance was obtained for the e.max CAD in the thickness of 1.5 mm (4995 N), being statistically superior to the other groups (p <0.05). The lowest fracture resistance was obtained for Vita Enamic at 0.6 mm thickness (2973 N), not being significantly different from e.max CAD 0.6 mm (3067 N), Lava Ultimate 0.6 mm (3384 N), Vita Enamic 1.5 mm (3540 N) and Lava Ultimate 1.5 mm (3584 N) (p>0.05). According to one- way ANOVA, the fracture resistance of the sound teeth (3991 N) did not differ significantly from the teeth with occlusal veneers (p> 0.05). The failures were predominantly repairable, except for sound teeth and Lava Ultimate 1.5 mm. The Lava Ultimate, e.max CAD and Vita Enamic occlusal veneers, in the thicknesses of 0.6 mm and 1.5 mm, showed fracture resistance exceeding the maximum masticatory forces. / O objetivo do estudo foi avaliar, in vitro, a resist?ncia ? fratura de facetas oclusais, confeccionadas por CAD/CAM, com os materiais Lava Ultimate, e.max CAD e Vita Enamic nas espessuras de 0,6 mm e 1,5 mm. Setenta terceiros molares humanos h?gidos foram aleatoriamente divididos em sete grupos (n=10) de acordo com as vari?veis material e espessura, tendo os dentes h?gidos como controle. A raiz dos dentes foi inserida em resina acr?lica quimicamente ativada e os dentes receberam um preparo para simular eros?o avan?ada da superf?cie oclusal. As restaura??es oclusais foram confeccionadas por meio da tecnologia CAD-CAM, sendo cimentadas ao preparo com sistemas adesivos e cimentos resinosos. Ap?s armazenagem em ?gua destilada a 37 ?C por 24 h, as amostras foram submetidas ? ciclagem mec?nica (1 milh?o de ciclos com carga de 100 N). Na sequ?ncia, os dentes h?gidos e as amostras com as facetas oclusais foram submetidas ao ensaio de resist?ncia ? fratura em m?quina de ensaio universal com velocidade de 1 mm/min. As falhas foram classificadas em repar?veis e irrepar?veis. De acordo com ANOVA de duas vias, a intera??o entre material e espessura foi significativa (p=0,013). A maior resist?ncia ? fratura foi obtida para o e.max CAD na espessura de 1,5 mm (4995 N), sendo estatisticamente superior aos demais grupos (p<0,05). A menor resist?ncia ? fratura foi obtida para o Vita Enamic na espessura de 0,6 mm (2973 N), n?o diferindo estatisticamente do e.max CAD 0,6 mm (3067 N), Lava Ultimate 0,6 mm (3384 N), Vita Enamic 1,5 mm (3540 N) e Lava Ultimate 1,5 mm (3584 N) (p>0,05). De acordo com ANOVA de uma via, a resist?ncia ? fratura dos dentes h?gidos (3991 N) n?o diferiu estatisticamente dos dentes com facetas oclusais (p>0,05). As falhas foram predominantemente do tipo repar?vel, com exce??o dos dentes h?gidos e Lava Ultimate 1,5 mm. As facetas oclusais em Lava Ultimate, e.max CAD e Vita Enamic, nas espessuras de 0,6 mm e 1,5 mm, demonstraram resist?ncia ? fratura que excede as for?as mastigat?rias m?ximas.

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