Freezing of stallion epididymal sperm

Inseminations with frozen-thawed epididymal sperm have resulted in low-pregnancy rates of mares. If fertility of epididymal sperm could be improved, it would help to preserve genetic material from stallions that have suffered severe injuries, been castrated or have died. The aim of the present study was to investigate the effect of different extenders and pre-freezing addition of capacitation media on freezability of epididymal sperm and on storage at 5 degrees C for 24 h. In experiment 1, epididymal sperm samples were diluted and subsequently frozen with three different extenders: Botu-Crio((R)), EDTA-Lactose and INRA-82. Motility analysis using computer assisted sperm analyzer (CASA) demonstrated better motility for sperm in Botu-Crio((R)) than in the other extenders; EDTA-Lactose yielded better motility than INRA-82 on most evaluated parameters. There was no difference in membrane integrity among the studied extenders. From 18 inseminated mares, 12 (66%) were pregnant 15 days after AI with frozen-thawed epididymal sperm showing that Botu-Crio((R)) was able to maintain the fertility potential. In experiment 2, the effect of incubation of epididymal sperm before freezing in three capacitation media (Fert Talp, Sperm Talp, Talp + Progesterone), seminal plasma, or control was tested. Based on post-thaw motility evaluation by CASA, samples incubated in Sperm Talp showed better motility values. There were no differences in plasma or acrosomal membranes or in mitochondrial potential among groups. We concluded that Botu-Crio((R)) was better than the other extenders in the ability to preserve epididymal sperm and that pre-freeze addition of Sperm Talp was also beneficial. (c) 2008 Published by Elsevier B.V.

Effect of Flasking and Polymerization Techniques on Tooth Movement in Complete Denture Processing

Purpose: The purpose of this study was to compare the artificial tooth positional changes following the flasking and polymerization of complete dentures by a combination of two flasking methods and two polymerization techniques using computer graphic measurements.Materials and Methods: Four groups of waxed complete dentures (n = 10) were invested and polymerized using the following techniques: (1) adding a second investment layer of gypsum and conventional water bath polymerization (Control), (2) adding a second investment layer of gypsum and polymerization with microwave energy (Gyp-micro), (3) adding a second investment layer of silicone (Zetalabor) and conventional polymerization (Silwater), and (4) adding a second investment layer of silicone and polymerization with microwave energy (Silmicro). For each specimen, six segments of interdental distances (A to F) were measured to determine the artificial tooth positions in the waxed and polymerized stages using software program AutoCad R14. The mean values of the changes were statistically compared by univariate ANOVA with Tukey post-hoc test at 5% significance.Results: There were no significant differences among the four groups, except for segment D of the Silmicro group (-0.004 +/- 0.032 cm) in relation to the Gypwater group (0.044 +/- 0.031 cm) (p < 0.05), which presented, repectively, expansion and shrinkage after polymerization.Conclusions: Within the limitations of this study, it was concluded that although the differences were not statistically significant, the use of a silicone investment layer when flasking complete dentures resulted in the least positional changes of the artificial teeth regardless of the polymerization technique.

Comparação entre os exames radiográficos convencional e digitalizado em relação ao plano de tratamento de superfícies oclusais

O objetivo deste estudo foi comparar as decisões de tratamento restaurador de superfícies oclusais, sem cavitação, quando realizadas através dos aspectos clínicos e radiográficos, convencional e digitalizado. Foram examinados, 33 sítios das superfícies oclusais de 30 molares permanentes extraídos, com e sem pigmentação. O plano de tratamento para cada região foi realizado por 5 cirurgiões-dentistas, professores universitários, utilizando dois tipos de exames: exame visual de fotografias e radiografia interproximal convencional (IV + RXC); e exame visual de fotografias e radiografia digitalizada (IV + DIGORA). O padrão de validação para os planos de tratamento foi realizado através do aspecto histológico. A sensibilidade em determinar a não-necessidade de tratamento restaurador foi, em média, tanto para a IV + RXC quanto para a IV + DIGORA, de 0,23. A especificidade foi, em média, de 0,83 e 0,86, para a IV + RXC e IV + DIGORA, respectivamente. Quando comparou-se os planos de tratamento intra-examinadores, não foi encontrada diferença estatisticamente significante à nível de 5%. Baseado nestes dados, pode-se concluir que os métodos radiográficos, convencional e digitalizado, não demonstraram diferenças na efetividade da determinação do plano de tratamento de superfícies oclusais sem cavitação.

Measurement of Interfacial Porosity at the Acrylic Resin/Denture Tooth Interface

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

New insights regarding HCV-NS5A structure/function and indication of genotypic differences

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Advances and Developments in Strategies to Improve Strains of Saccharomyces cerevisiae and Processes to Obtain the Lignocellulosic Ethanol-A Review

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Propriedades eletrônicas, estruturais e constantes elásticas do ZnO

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Jogo da Minoria: um modelo baseado em agentes aplicado ao mercado financeiro

Nos últimos anos houve uma contribuição significativa dos físicos para a construção de um tipo de modelo baseado em agentes que busca reproduzir, em simulação computacional, o comportamento do mercado financeiro. Esse modelo, chamado Jogo da Minoria consiste de um grupo de agentes que vão ao mercado comprar ou vender ativos. Eles tomam decisões com base em estratégias e, por meio delas, os agentes estabelecem um intrincado jogo de competição e coordenação pela distribuição da riqueza. O modelo tem demonstrado resultados bastante ricos e surpreendentes, tanto na dinâmica do sistema como na capacidade de reproduzir características estatísticas e comportamentais do mercado financeiro. Neste artigo, são apresentadas a estrutura e a dinâmica do Jogo da Minoria, bem como as contribuições recentes relacionadas ao Jogo da Minoria denominado de Grande Canônico, que é um modelo mais bem ajustado às características do mercado financeiro e reproduz as regularidades estatísticas do preço dos ativos chamadas fatos estilizados.

A low cost structured light system

The aim of this paper is to present the current development status of a low cost system for surface reconstruction with structured light. The acquisition system is composed of a single off-the-shelf digital camera and a pattern projector. A pattern codification strategy was developed to allow the pattern recognition automatically and a calibration methodology ensures the determination of the direction vector of each pattern. The experiments indicated that an accuracy of 0.5mm in depth could be achieved for typical applications.

A human retrieval study of plasma-sprayed hydroxyapatite-coated plateau root form implants after 2 months to 13 years in function

Calcium phosphate-based bioactive ceramics in various physical and chemical formulations have been extensively utilized as biomaterials for bone regeneration/conduction. However, the determination of their in vivo temporal behavior from the short to long term in humans has been a challenge due to the lack of physical reference for morphologic and morphometric evaluation. The present study evaluated bone morphology and morphometry (bone-to-implant contact [BIC]) around plasma-sprayed hydroxyapatite (PSHA)-coated endosseous implants that were retrieved due to prosthetic reasons while successfully in function at the posterior region of the jaws from as early as 2 months to ~13 years after a 6-month healing period after placement. Bone morphology was evaluated by light microscopy, and BIC was determined using computer software. Irrespective of the time in vivo, lamellar bone was observed in close contact with the implant PSHA-coated surface and between plateaus. BIC ranged from ~35-95%, was highly directional, and Haversian-like osteonic morphology between plateaus was observed for most implants. The PSHA coating was present with little variation in thickness between the samples retrieved regardless of time in vivo. © 2010 by Begell House, Inc.

Evaluation of the dentin-pulp complex after cavity preparation with ultrasonic diamond tip

The aim of this paper was to compare the dentin-pulp complex response to cavity preparation in human teeth using ultrasonic chemical vapor deposition (CVD) diamond tip and high-speed diamond bur. Class V buccal cavities were randomly prepared in 40 premolars from 14 patients aged 11 to 15 years. The cutting time was recorded and the cavities had the axial walls protected with gutta-percha and were filled with glass ionomer cement. The teeth were extracted at intervals of 0, 5, 10 and 20 days, and were decalcified, sectioned and stained by Hematoxylin & Eosin, Masson's Trichrome and Brown & Brenn techniques. The inflammatory response and cell disorganization were blindly evaluated by two examiners. The remaining dentin thickness (RDT) was measured by a linear scale using computer software. Statistical analysis by one-way ANOVA showed no statistically significant difference (P≤0.05) among the cavities prepared with either type of instrument, with mean RDT of 1132.50 mm. Cutting time and the pulp-dentin complex responses were analyzed statistically by Kruskal-Wallis and Dunn tests (P≤0.05). The ultrasonic CVD diamond tip took 5 times longer to prepare the cavities and there were no typical inflammatory pulp responses in cavities prepared with either type of cutting instrument, only mild to moderate cell disorganization was present. Even taking longer to cut the dental substrate, the ultrasonic CVD diamond tip produced similar pulp response compared to the conventional high-speed diamond bur.

Classificação da curvatura de vertentes em perfil via Thin Plate Spline e Inferência Fuzzy

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modelagem numérica do escoamento em válvulas automáticas de compressores pelo Método da Fronteira Imersa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ensaio sobre o fluxo de Ricci e os buracos negros: fundamentação e estudo computacional

Pós-graduação em Ciência da Computação - IBILCE

Estudo da dinâmica do sistema Prometeu - Pandora - anel F de saturno

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)