553 research outputs found

    BENCHMARKING OF TWO SYSTEMS FOR TRANSMISSION OF MOTION FOR A DOUBLE ACTION STIRLING ENGINE

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    In a four-piston Stirling engine, Siemens configuration, the displacement of the pistons is governed by the motion transmission element, which converts the reciprocating motion of pistons into rotary motion. This study aimed to evaluate the influence of the geometry of the transmission element in the mechanical efficiency of a Stirling engine. Analyses were performed using a mathematical computer simulation that uses the geometric and operating data of the engine to calculate the mechanical power and efficiency through a first order thermodynamic mathematical model, also known as the Schmidtmodel. First, an analysis was performed to evaluate the mechanical efficiency of the transmission element with a sinusoidal curve surface. Later, it was implemented in the transmission mechanism a segment based straight plans surface, and then the same analysis was performed with this new transmission element. The results showed that using the transmission element with segment based straight plans the engine showed a significant increase in efficiency. Moreover, one can observe an increase in the vibration of the system, making it necessary to develop an appropriate system for balancing

    Evaluating oral health-related quality of life measure for children and preadolescents with temporomandibular disorder

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    Background: Oral health-related quality of life (OHRQoL) in children and adolescents with signs and symptoms of temporomandibular disorder (TMD) has not yet been measured. This study aimed to evaluate the validity and reliability of OHRQoL measure for use in children and preadolescents with signs and symptoms of TMD.Methods: Five hundred and forty-seven students aged 8-14 years were recruited from public schools in Piracicaba, Brazil. Self-perceptions of QoL were measured using the Brazilian Portuguese versions of Child Perceptions Questionnaires (CPQ)(8-10) (n = 247) and CPQ(11-14) (n = 300). A single examiner, trained and calibrated for diagnosis according to the Axis I of the Research Diagnostic Criteria for TMD (RDC/TMD), examined the participants. A self-report questionnaire assessed subjective symptoms of TMD. Intraexaminer reliability was assessed for the RDC/TMD clinical examinations using Cohen's Kappa (kappa) and intraclass correlation coefficient (ICC). Criterion validity was calculated using the Spearman's correlation, construct validity using the Spearman's correlation and the Mann-Whitney test, and the magnitude of the difference between groups using effect size (ES). Reliability was determined using Cronbach's alpha, alpha if the item was deleted and corrected item-total correlation.Results: Intraexaminer reliability values ranged from regular (kappa = 0.30) to excellent (kappa = 0.96) for the categorical variables and from moderate (ICC = 0.49) to substantial (ICC = 0.74) for the continuous variables. Criterion validity was supported by significant associations between both CPQ scores and pain-related questions for the TMD groups. Mean CPQ(8-10) scores were slightly higher for TMD children than control children (ES = 0.43). Preadolescents with TMD had moderately higher scores than the control ones (ES = 0.62; p < 0.0001). Significant correlation between the CPQ scores and global oral health, as well as overall well-being ratings (p < 0.001) occurred, supporting the construct validity. the Cronbach's alphas were 0.93 for CPQ(8-10) and 0.94 for CPQ(11-14). for the overall CPQ(8-10) and CPQ(11-14) scales, the corrected item-total correlation coefficients ranged from 0.39-0.76 and from 0.28-0.73, respectively. the alpha coefficients did not increase when any of the items were deleted in either CPQ samples.Conclusions: the questionnaires are valid and reliable for use in children and preadolescents with signs and symptoms of temporomandibular disorder.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ Estadual Campinas, Piracicaba Dent Sch, Dept Pediat Dent, Piracicaba, SP, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, Diadema, SP, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, Diadema, SP, BrazilFAPESP: 2008/00325-9Web of Scienc

    Banco de dados geográfico sobre a cafeicultura mineira: organização lógica e inserção de dados.

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    Os sistemas de informações geográficas (SIG) foram desenvolvidos com o objetivo de facilitar o tratamento de um volume cada vez maior e mais preciso de informações sobre a superfície terrestre e suas questões ambientais. Na utilização para a cafeicultura o SIG integra softwares para tratamento e armazenamento de dados segundo um modelo conceitual predefinido. A partir da definição deste modelo iniciou-se o armazenamento dos dados, em um Sistema de Gerenciamento de Banco de Dados (SGBD). A ferramenta escolhida para o gerenciamento dos dados foi o PostgreSQL pois este é um SGBD objeto-relacional e de código aberto, mantido em constantes atualizações gratuitas pela Comunidade Brasileira do PostgreSQL 1. Devido ao grande número de atualizações, o PostgreSQL é extensível, sendo utilizado para dar suporte à diversos tipos de aplicações desde dados simples à aplicações mais complexas, bem como seus metadados. Para a integração e o armazenamento dos dados foi utilizado o sistema de informação geográfico SPRING 2. O SPRING é um software gratuito para criação e gerenciamento de banco de dados geográficos, possuí funções para processamento de imagens, análises espaciais, modelagem numérica de terreno e consulta a banco de dados espaciais. No acesso aos dados geográficos foi utilizado um tipo de arquitetura conhecida como ?Arquitetura Dual?. A principal vantagem desta arquitetura consiste na separação das funcionalidades na qual o gerenciamento dos metadados é feita pelo SGBD, pois os mecanismos de transação, recuperação a falhas, concorrência, integridade dos dados e indexação podem ser usados para a parte não espacial dos dados, enquanto que a responsabilidade do gerenciamento dos dados geográficos é realizada pelo SPRING. Portanto, o objetivo principal deste trabalho foi inserir e organizar dados geográfico sobre pesquisas realizadas pela EPAMIG relacionadas á cafeicultura mineira

    Effect of flint corn processing method and roughage level on finishing performance of Nellore-based cattle

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    Citation: Caetano, M., Goulart, R. S., Silva, S. L., Drouillard, J. S., Leme, P. R., & Lanna, D. P. D. (2015). Effect of flint corn processing method and roughage level on finishing performance of Nellore-based cattle. Journal of Animal Science, 93(8), 4023-4033. doi:10.2527/jas2015-9051This study was conducted to evaluate the effects of flint corn processing method (CPM) and level of NDF from roughage (rNDF) on performance, carcass characteristics, and starch utilization by finishing Nellore-based cattle fed high-concentrate, flint corn-based diets. In this study, 112 Nellore type bulls (initial BW 384.07 +/- 29.53 kg and 24-36 mo of age) were individually fed using Calan gates or individual pens. The animals were used in a randomized complete block design in a 2 x 4 factorial arrangement with 2 CPM, high-moisture flint corn (HMC) or finely ground dry flint corn (FGC), with 1 of 4 levels of rNDF, 3, 8, 13, and 18% (DM basis), using sugarcane silage (SS) as roughage. Bulls were adapted to the finishing diet over a 21-d period and fed for a total of 81 d. Fecal starch (FS) concentration was determined on d 46 and 74 of the feeding period. There was a quadratic effect of rNDF on final BW (P < 0.01) and ADG (P = 0.01). Optimal concentrations of rNDF were estimated using the first derivative of second order polynomials, indicating that final BW and ADG were maximized with 13.3 and 13.0% rNDF, respectively. An interaction was observed between CPM and rNDF (P = 0.05) for DMI, with peak DMI occurring at 11.3 and 13.7% rNDF with FGC and HMC, respectively. Cattle fed HMC had 13.9% greater G:F (P < 0.01) compared with those fed FGC (0.172 vs. 0.151, respectively). There were quadratic effects of rNDF on HCW (P = 0.04) and ME intake (P < 0.01); heaviest carcass weights were estimated, in both cases, to be achieved with 12.8% rNDF. A quadratic effect of rNDF for renal, pelvic, and inguinal fat weight (P = 0.04) was observed, with a peak estimated to occur at 12.6% rNDF. An interaction between CPM and rNDF also was observed for FS (P < 0.05). Bulls fed FGC with 3% rNDF had greater FS content, and FS linearly decreased as concentration of rNDF increased. For bulls fed HMC, FS was 3.0% of DM and was unaffected by rNDF in the diet. Lower FS from bulls fed HMC suggests that availability of starch from flint corn was greater than that of FGC. For Nellore-based cattle fed a flint corn-based diet containing SS and 8% whole lint cottonseed, performance was optimized with 12.8% rNDF. In the absence of cottonseed addition to diets, optimal performance would be expected with about 14.5% rNDF

    Processo de desenvolvimento de um site utilizando Web Mapping para o laboratório de geoprocessamento geosolos.

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    Em virtude dos avanços técnico-científicos, observa-se nos dias atuais o aumento expressivo na disponibilização de dados na Internet, de modo a facilitar o acesso aos mais diversos tipos de dados, tendo em vista as inovações proporcionadas com as novas e modernas ferramentas tecnológicas, que têm beneficiado o incremento e o uso de novos instrumentos (MOREIRA, 2010). Além dos avanços expressivos no campo informacional e tecnológico, como destaca Medeiros et al. (2010), podemos referenciar o geoprocessamento e os Sistemas de Informações Geográficas ? SIG?s que, aliados à Internet, tornaram-se tecnologias ainda mais robustas para divulgar os mais diversos tipos de informações. O uso da web como um meio de divulgação para os mapas pode ser considerado como um grande avanço na cartografia e abre muitas novas oportunidades, tais como mapas em tempo real, com divulgação mais barata e atualizações mais freqüentes, contendo mapas personalizados e interativos. O objetivo deste trabalho foi justamente a criação de um ambiente web, que propiciasse a divulgação dos mapas e trabalhos de pesquisa realizados pela equipe do laboratório de geoprocessamento da EPAMIG - GeoSolos, que utiliza geotecnologias para, entre outras coisas, mapear e caracterizar o café em grandes regiões produtoras de Minas Gerais. O público-alvo deste portal são todos os integrantes da cadeia produtiva do café, pesquisadores da área e pessoas interessadas nestas geotecnologias e na aplicação destas para o mapeamento do café

    Transcripts levels of enzymes involved in histone acetylation in bovine oocytes of different competences.

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    Proceedings of the 31st Annual Meeting of the Brazilian Embryo Technology Society (SBTE); Cabo de Santo Agostinho, PE, Brazil, August 17th to 19th, 2017. Abstract
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