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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.
31

Anestesia peribulbar guiada por ultrassom com diferentes volumes de ropivacaína a 1 por cento associada ou não ao bicarbonato de sódio em cães /

Wagatsuma, Juliana Tessália. January 2016 (has links)
Orientador: Valéria Nobre Leal de Souza Oliva / Banca: Paulo Sérgio Patto dos Santos / Banca: Alexandre Lima de Andrade / Banca:Antonio José de Araújo Aguiar / Banca: Verônica Batista de Albuquerque / Resumo:Sete cães foram submetidos à anestesia inalatória com isoflurano para permitir a realização do bloqueio peribulbar, com punção única inferior, guiado por ultrassonografia com ropivacaína a 1%, e assim comprovar a eficácia desta técnica de bloqueio guiado na redução do volume anestésico injetado de ropivacaína a 1%, e avaliar possíveis efeitos potencializadores como a redução da latência e do volume anestésico utilizado, assim como complicações oftálmicas associadas à alcalinização do anestésico com bicarbonato de sódio a 0,33%. Foram avaliados dois volumes diferentes de ropivacaína a 1% (0,2 mL/Kg e 0,1 mL/Kg) associados ou não ao bicarbonato de sódio a 0,33% que, ao ser adicionado ao anestésico, elevou o pH da solução anestésica para 6,0. Uma vez realizado o bloqueio peribulbar, com punção única inferior, guiado por ultrassom o tempo necessário para ocorrer a centralização do bulbo do olho era cronometrado, e os animais permaneciam anestesiados para a aferição da pressão intraocular, que foi realizada imediatamente e 15 minutos após o bloqueio e, concluída essa mensuração, a anestesia foi encerrada. Com os cães já despertos foram avaliados os seguintes parâmetros: a pressão intraocular, o diâmetro pupilar, o bloqueio motor, sensitivo (realizado por meio de estesiometria corneal com estesiômetro de Cochet e Bonnet), e a observação das intercorrências oftálmicas como quemose, hiperemia conjuntival, hematoma subconjuntival, prurido e secreção ocular. As análises estatísticas foram conduzidas com o auxílio do software de livre acesso RStudio . Variáveis não paramétricas, ordinais e categóricas foram avaliadas por teste estatística tipo ANOVA ou ATS. Variáveis contínuas paramétricas foram avaliadas pelo Modelo linear misto para medidas repetidas. O Teste Kendall Tau-b foi utilizado... (resumo completo clicar acesso eletronico abaixo) / Abstract: Seven dogs were subjected to inhalation anesthesia with isoflurane to allow the realization of peribulbar block, with lower single puncture, guided by ultrasound with 1% ropivacaine, and thus prove the effectiveness of this blocking technique guided in reducing anesthetic volume of ropivacaine 1%, and evaluate possible potentiating effects such as reducing the latency and anesthetic volume used and ophthalmic complications associated with the anesthetic alkalinization with sodium bicarbonate 0,33%. We evaluated two different volumes of 1% ropivacaine (0.2 ml / kg and 0.1 ml / kg) with or without sodium bicarbonate to 0.33% which when added to anesthetic raised the pH of the solution anesthetic to 6.0. Once performed peribulbar block, with lower single puncture guided by ultrasound time required to place the centralization of the eye bulb was timed, and the animals remained anesthetized for the measurement of intraocular pressure was carried out immediately and 15 minutes after blockade and completed this measurement, anesthesia was terminated. With dogs the following parameters already awake were evaluated intraocular pressure, pupil size, the duration and intensity of motor block, sensory (performed by esthesiometry corneal with esthesiometer Cochet and Bonnet), and observation of ophthalmic complications as chemosis, conjunctival hyperemia, subconjunctival hematoma, pruritus, and ocular secretion resulting from the anesthetic technique or employee drug. Statistical analyzes... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
32

Tampões em diluentes para resfriamento de sêmen equino. / Buffers in extenders for cooling equine semen

Trentin, Janislene Mach January 2014 (has links)
Nesse estudo comparou-se o efeito tamponante do HEPES e Bicarbonato de Sódio em manter o pH e a viabilidade do sêmen resfriado de pôneis da raça Brasileira. As alterações no pH ocasionadas por diferentes diluições com diluente a base de leite desnatado em pó sem tampão a 5 e a 15°C também foram medidas. No experimento 1 avaliou-se o efeito da diluição e da temperatura de resfriamento sobre a motilidade, integridade de membrana, pH e atividade mitocondrial do sêmen pré e pós resfriamento. O sêmen de nove pôneis da raça Brasileira (dois ejaculados/pônei) foi diluído em diluente a base de leite desnatado (em pó) sem tampão e refrigerado a 5 ou 15°C por 48h em três diferentes diluições (1+1, 1+2, 1+3). As três diluições não alteraram os parâmetros avaliados após a diluição a fresco. A diluição 1+1 resultou em valores maiores de pH (7,63 e 7,57, respectivamente) e menor percentual de motilidade progressiva (MP) a 5 e a 15°C. O maior percentual de células íntegras (1+1=44,16; 1+2=48,16; 1+3=50,05) foi detectado a 15°C (P < 0,01), independente da diluição. A MP foi maior nas 48h de resfriamento (39,72%; P < 0,05) quando o sêmen foi diluído a 1+3 e refrigerado a 15°C. A atividade mitocondrial (P > 0,05) em função do tempo e temperatura foi similar entre as diluições. No experimento 2 avaliou-se o efeito tampão do bicarbonato de sódio e do HEPES em diluentes sobre a viabilidade de espermatozoides resfriados a 5°C durante 48h. Os diluentes testados compunham-se de leite desnatado em pó com bicarbonato de sódio (A), HEPES (B) ou diluente sem tampão (C). O sêmen de sete pôneis da raça Brasileira (três ejaculados/pônei) foi utilizado e a motilidade progressiva foi similar entre os diluentes (P > 0,05) após a diluição. Nas 24 e 48h, a MP foi, respectivamente, para A (44,76%; 25,23%), B (51,42%; 38,09%) e C (54,05%; 41,66%). A integridade da membrana plasmática foi similar após a exposição aos três diluentes. A fresco, a atividade mitocondrial foi maior (P < 0,05) no sêmen exposto ao diluente A (A=1,05nm, B=0,81nm, C=0,79nm) e após 24h A e B foram similares (0,83nm; 0,73nm), enquanto que no diluente C observou-se menor atividade (0,64nm). Nas 48h não houve diferença (A=0,72; B=0,69; C=0,63; P > 0,05). O pH do diluente e sua osmolaridade, assim como o pH do sêmen diluído foi maior no diluente A (8; 382; 7,9), intermediário (7,5; 362; 7,32) no B e menor no C (7,16; 350; 7,07). A peroxidação lipídica e a indução da peroxidação foram similares em todos os grupos. Sugere-se que, quando da utilização do sêmen a fresco, qualquer das diluições aqui testadas pode ser utilizada com segurança. O resfriamento do sêmen por 48h modifica e eleva o pH do sêmen. Os melhores resultados foram observados com o resfriamento do sêmen a 15°C por 48h e com a diluição 1+3 em um diluente a base de leite em pó desnatado sem tampão. O bicarbonato de sódio (A) reduz a MP e aumenta o pH do sêmen. O diluente sem tampão foi considerado o mais apropriado para uso imediato na IA. Tanto o diluente com HEPES, quanto o diluente sem tampão foram adequados para o resfriamento do sêmen equino a 5°C durante 48h. / This study compared the buffering effect of HEPES and sodium bicarbonate on pH and viability of Brazilian pony semen cooled at 5°C. pH changes caused by different dilutions using skim milk powder semen extender without buffer were also measured. In experiment 1, the effect of dilution and cooling temperature on semen motility, membrane integrity, mitochondrial activity and pH pre and post cooling was investigated. Ejaculates of nine Brazilian ponies (two ejaculates per pony) were diluted, of a non buffered powder milk extender and cooled at 5°C or 15°C during 48h in three different dilutions (1+1, 1+2 and 1+3). Dilutions did not change the parameters evaluated before cooling. Samples diluted 1+1 resulted in higher pH values (7.63 and 7.57, respectively) and lowest percentage of progressive motility (PM) at 5 and 15°C. All samples cooled at 15°C showed a lower incidence of abnormal spermatozoa (1+1 = 55.84%; 1+2 = 51.84%; 1+3 = 49.95%) (P < 0.01) independent of dilution. Progressive motility was higher when semen was cooled during 48h in 1+3 dilution at 15°C (39.72%; P < 0.05). Mitochondrial activity despite of time and temperature was similar (P > 0.05) among dilutions. In experiment 2, the buffer effect of sodium bicarbonate and HEPES on extenders were evaluated considering the maintenance of sperm viability after cooling at 5°C during 24 and 48h. A non-buffered milk powder extender (C = control) and the same extender buffered with Sodium Bicarbonate (A) and HEPES (B) was used. Semen from 7 Brazilian ponies (three ejaculates / pony) was used. Immediately after dilution sperm motility was evaluated and progressive motility was similar with all extenders (P > 0.05). At 24 and 48h after cooling at 5oC sperm motility was evaluated, respectively, on groups A (44.76%; 25.23%), B (51.42%; 38.09%) and C (54.05%; 41.66%). Plasma membrane integrity was similar after exposure to the three extenders. Before cooling, mitochondrial activity was higher (P <0.05) in extender A (A = 1.05nm, B = 0.81nm, C = 0.79nm). Mitochondrial activity after cooling for 24h was 0.83nm (A), 0.73nm (B) and 0.64nm (C). After 48h it decreased to 0.72nm (A), 0.69nm (B) and 0.63nm (C) (P > 0.05), respectively. The extenders pH, osmolarity and pH of diluted semen was higher in A (8; 382; 7.9), intermediate in B (7.5; 362; 7.32) and lower in C (7.16; 350; 7.07). Lipid peroxidation and its induction were similar in all groups. It was concluded that all dilution grades in fresh semen were adequate and that pH was affected and increased when semen was extended and cooled for 48h. The best results were observed when semen was diluted at 1+3 and cooled at 15°C for 48h in a non buffered powder milk extender. Sodium bicarbonate (A) reduces progressive motility and increases semen pH. The non buffered (C) semen extender was considered more appropriated for semen dilution for immediate use in artificial insemination. The non buffered and HEPES buffered semen extenders were considered appropriated for cooling equine semen at 5°C during 48h.
33

Tampões em diluentes para resfriamento de sêmen equino. / Buffers in extenders for cooling equine semen

Trentin, Janislene Mach January 2014 (has links)
Nesse estudo comparou-se o efeito tamponante do HEPES e Bicarbonato de Sódio em manter o pH e a viabilidade do sêmen resfriado de pôneis da raça Brasileira. As alterações no pH ocasionadas por diferentes diluições com diluente a base de leite desnatado em pó sem tampão a 5 e a 15°C também foram medidas. No experimento 1 avaliou-se o efeito da diluição e da temperatura de resfriamento sobre a motilidade, integridade de membrana, pH e atividade mitocondrial do sêmen pré e pós resfriamento. O sêmen de nove pôneis da raça Brasileira (dois ejaculados/pônei) foi diluído em diluente a base de leite desnatado (em pó) sem tampão e refrigerado a 5 ou 15°C por 48h em três diferentes diluições (1+1, 1+2, 1+3). As três diluições não alteraram os parâmetros avaliados após a diluição a fresco. A diluição 1+1 resultou em valores maiores de pH (7,63 e 7,57, respectivamente) e menor percentual de motilidade progressiva (MP) a 5 e a 15°C. O maior percentual de células íntegras (1+1=44,16; 1+2=48,16; 1+3=50,05) foi detectado a 15°C (P < 0,01), independente da diluição. A MP foi maior nas 48h de resfriamento (39,72%; P < 0,05) quando o sêmen foi diluído a 1+3 e refrigerado a 15°C. A atividade mitocondrial (P > 0,05) em função do tempo e temperatura foi similar entre as diluições. No experimento 2 avaliou-se o efeito tampão do bicarbonato de sódio e do HEPES em diluentes sobre a viabilidade de espermatozoides resfriados a 5°C durante 48h. Os diluentes testados compunham-se de leite desnatado em pó com bicarbonato de sódio (A), HEPES (B) ou diluente sem tampão (C). O sêmen de sete pôneis da raça Brasileira (três ejaculados/pônei) foi utilizado e a motilidade progressiva foi similar entre os diluentes (P > 0,05) após a diluição. Nas 24 e 48h, a MP foi, respectivamente, para A (44,76%; 25,23%), B (51,42%; 38,09%) e C (54,05%; 41,66%). A integridade da membrana plasmática foi similar após a exposição aos três diluentes. A fresco, a atividade mitocondrial foi maior (P < 0,05) no sêmen exposto ao diluente A (A=1,05nm, B=0,81nm, C=0,79nm) e após 24h A e B foram similares (0,83nm; 0,73nm), enquanto que no diluente C observou-se menor atividade (0,64nm). Nas 48h não houve diferença (A=0,72; B=0,69; C=0,63; P > 0,05). O pH do diluente e sua osmolaridade, assim como o pH do sêmen diluído foi maior no diluente A (8; 382; 7,9), intermediário (7,5; 362; 7,32) no B e menor no C (7,16; 350; 7,07). A peroxidação lipídica e a indução da peroxidação foram similares em todos os grupos. Sugere-se que, quando da utilização do sêmen a fresco, qualquer das diluições aqui testadas pode ser utilizada com segurança. O resfriamento do sêmen por 48h modifica e eleva o pH do sêmen. Os melhores resultados foram observados com o resfriamento do sêmen a 15°C por 48h e com a diluição 1+3 em um diluente a base de leite em pó desnatado sem tampão. O bicarbonato de sódio (A) reduz a MP e aumenta o pH do sêmen. O diluente sem tampão foi considerado o mais apropriado para uso imediato na IA. Tanto o diluente com HEPES, quanto o diluente sem tampão foram adequados para o resfriamento do sêmen equino a 5°C durante 48h. / This study compared the buffering effect of HEPES and sodium bicarbonate on pH and viability of Brazilian pony semen cooled at 5°C. pH changes caused by different dilutions using skim milk powder semen extender without buffer were also measured. In experiment 1, the effect of dilution and cooling temperature on semen motility, membrane integrity, mitochondrial activity and pH pre and post cooling was investigated. Ejaculates of nine Brazilian ponies (two ejaculates per pony) were diluted, of a non buffered powder milk extender and cooled at 5°C or 15°C during 48h in three different dilutions (1+1, 1+2 and 1+3). Dilutions did not change the parameters evaluated before cooling. Samples diluted 1+1 resulted in higher pH values (7.63 and 7.57, respectively) and lowest percentage of progressive motility (PM) at 5 and 15°C. All samples cooled at 15°C showed a lower incidence of abnormal spermatozoa (1+1 = 55.84%; 1+2 = 51.84%; 1+3 = 49.95%) (P < 0.01) independent of dilution. Progressive motility was higher when semen was cooled during 48h in 1+3 dilution at 15°C (39.72%; P < 0.05). Mitochondrial activity despite of time and temperature was similar (P > 0.05) among dilutions. In experiment 2, the buffer effect of sodium bicarbonate and HEPES on extenders were evaluated considering the maintenance of sperm viability after cooling at 5°C during 24 and 48h. A non-buffered milk powder extender (C = control) and the same extender buffered with Sodium Bicarbonate (A) and HEPES (B) was used. Semen from 7 Brazilian ponies (three ejaculates / pony) was used. Immediately after dilution sperm motility was evaluated and progressive motility was similar with all extenders (P > 0.05). At 24 and 48h after cooling at 5oC sperm motility was evaluated, respectively, on groups A (44.76%; 25.23%), B (51.42%; 38.09%) and C (54.05%; 41.66%). Plasma membrane integrity was similar after exposure to the three extenders. Before cooling, mitochondrial activity was higher (P <0.05) in extender A (A = 1.05nm, B = 0.81nm, C = 0.79nm). Mitochondrial activity after cooling for 24h was 0.83nm (A), 0.73nm (B) and 0.64nm (C). After 48h it decreased to 0.72nm (A), 0.69nm (B) and 0.63nm (C) (P > 0.05), respectively. The extenders pH, osmolarity and pH of diluted semen was higher in A (8; 382; 7.9), intermediate in B (7.5; 362; 7.32) and lower in C (7.16; 350; 7.07). Lipid peroxidation and its induction were similar in all groups. It was concluded that all dilution grades in fresh semen were adequate and that pH was affected and increased when semen was extended and cooled for 48h. The best results were observed when semen was diluted at 1+3 and cooled at 15°C for 48h in a non buffered powder milk extender. Sodium bicarbonate (A) reduces progressive motility and increases semen pH. The non buffered (C) semen extender was considered more appropriated for semen dilution for immediate use in artificial insemination. The non buffered and HEPES buffered semen extenders were considered appropriated for cooling equine semen at 5°C during 48h.
34

NÃveis de sÃdio para codornas japonesas (Coturnix xotunix japonica) nas fases de crecimento e postura / Sodium levels for japanese quail (Coturnix coturnix japonica) in the growing and production phases

Raffaella Castro Lima 25 March 2009 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Com o objetivo de avaliar os efeitos dos nÃveis de sÃdio da raÃÃo nas fases de crescimento e de postura de codornas japonesas foram realizados dois experimentos, nos quais, foram avaliados os nÃveis de 0,07; 0,12; 0,17; 0,22; 0,27 e 0,32% de sÃdio. No primeiro experimento (fase de crescimento), 480 codornas com um dia de idade, foram distribuÃdas em um delineamento inteiramente casualizado, com seis tratamentos de oito repetiÃÃes de dez aves cada. Conforme os resultados, no perÃodo de 1 a 21 dias, houve aumento linear do consumo de raÃÃo e Ãgua com aumento dos nÃveis de sÃdio e efeito quadrÃtico no ganho de peso e conversÃo alimentar com nÃveis Ãtimos de 0,23% e 0,21% de sÃdio, respectivamente. De 21 a 42 dias, houve reduÃÃo linear no ganho de peso, aumento linear no consumo de Ãgua e prejuÃzo na conversÃo alimentar com o acrÃscimo de sÃdio na raÃÃo, enquanto, o consumo de raÃÃo nÃo foi influenciado. No perÃodo total (1 a 42 dias de idade) com o aumento de sÃdio na raÃÃo, observou-se aumento linear no consumo de Ãgua e na umidade das excretas e efeito quadrÃtico sobre a digestibilidade da matÃria seca (CDMS), nitrogÃnio (CDN), energia bruta (CDEB) e valores energia metabolizÃvel aparente (EMA) e aparente corrigida (EMAn) com nÃveis Ãtimos estimados de 0,20% para CDMS, 0,27% para o CDN e 0,19% para CDEB, EMA e EMAn. Ainda, nesse ensaio, observou-se que o desempenho da fase de postura nÃo foi influenciado significativamente pelo nÃvel de sÃdio recebido pelas codornas na fase de crescimento. No segundo experimento, 288 codornas com 16 semanas de idade foram distribuÃdas ao acaso em seis tratamentos com oito repetiÃÃes de seis aves por unidade experimental. Houve aumento linear do consumo de raÃÃo, consumo de Ãgua e peso do ovo com o acrÃscimo de sÃdio e efeito quadrÃtico para produÃÃo de ovos, massa de ovo e conversÃo alimentar com nÃveis Ãtimos de 0,23%, 0,24% e 0,23% de sÃdio, respectivamente. TambÃm, houve efeito quadrÃtico dos nÃveis de sÃdio para as percentagens de gema, casca e albÃmen, obtendo-se mÃxima proporÃÃo de albÃmen e casca e mÃnima de gema com 0,21% de sÃdio. NÃo houve efeito significativo dos nÃveis de sÃdio para Unidades Haugh, entretanto houve feito quadrÃtico para gravidade especÃfica, com nÃvel Ãtimo de 0,22% de sÃdio. O acrÃscimo de sÃdio nÃo afetou a umidade das excretas, mas houve efeito quadrÃtico sobre a digestibilidade da matÃria seca (CDMS), nitrogÃnio (CDN), energia bruta (CDEB) e valores energia metabolizÃvel aparente (EMA) e aparente corrigida (EMAn) com nÃveis Ãtimos estimados de 0,24% para CDMS, 0,22% para CDN, 0,21% para CDEB e 0,18% para EMA e EMAn. Considerando os resultados, pode-se recomendar que as raÃÃes para codornas japonesas na fase de crescimento (1 a 42 dias) sejam formuladas com nÃveis de sÃdio entre 0,12% e 0,23% e na fase de produÃÃo, com nÃveis entre 0,18% e 0,23% de sÃdio / With the aim to evaluate the effects of the sodium levels in the growth and laying phases of Japanese quails, we conducted two experiments in which we evaluated the sodium levels of de 0,07%; 0,12%; 0,17%; 0,22%; 0,27% and 0,32%. In the first experiment (growth phase), 480 quails with one day were distributed in a completely randomized design with six treatments of eight replications of ten birds each. According to the results, in the period from 1 to 21 days, there was a linear increase in feed and water intake with the increase in sodium levels and a quadratic effect in the weight gain and feed conversion with optimum sodium levels of 0,23% and 0,21%, respectively. In the period from 21 to 42 days, there was a linear reduction in the weight gain, linear increase in water intake and worse in feed conversion with the increase in sodium in the ration, while feed intake was not affected. In the total period (1 to 42 days of age) with the increase in sodium in the ration, we observed a linear increase in the water intake and in the excreta moisture and a quadratic effect on the digestibility of the dry matter (DCMS), nitrogen (CDN), gross energy (DCEB) and values of apparent metabolizable energy (AME) and apparent corrected (AMEn) with estimated optimum levels of 0,20% for DCMS, 0,27% for CDN and 0,19% for DCEB, AME and AMEn. Moreover, in this experiment we observed that the performance of the laying phase was not influenced significantly by the sodium level supplied to quails in the growth phase. In the second experiment, 288 quails with 16 weeks of age were distributed at random in six treatments with eight replications of six birds each. There was a linear increase in feed intake, in water intake, and in egg weight with the increase in sodium levels and a quadratic effect for egg production, egg mass and feed conversion with optimum sodium levels of 0,23%, 0,24% and 0,23%, respectively. Also, there was a quadratic effect of the sodium levels for percentages the yolk, shell and albumen, obtaining a maximum proportion of albumen and shell and a minimum proportion of yolk with a 0,21% sodium level. There was no significant effect of the sodium levels for the Haugh Units. However, there was a quadratic for specific gravity, with an optimum sodium level of 0.22%. The increase in sodium content did not affect the excreta moisture, but there was a quadratic effect on the digestibility of dry matter (DCMS), nitrogen (CDN), gross energy (DCEB) and values of apparent metabolizable energy (AME) and apparent corrected (AMEn) with estimated optimum levels of 0,24% for CDMS, 0,22% for CDN, 0,21% for CDEB and 0,18% for AME and AMEn. Considering the results, we can recommend that the diets for Japanese quails in the growth phase (1 to 42 days) are formulated with sodium levels between 0,12% and 0,23% and in the production phase with sodium levels between 0,18% and 0,23%
35

Influência do tempo de aplicação do bicarbonato de sódio a 10% na adesão ao esmalte bovino clareado: estudo in vitro / Effect of the application time of 10% sodium bicarbonate on bleached enamel: an in vitro study

Marina Studart Alencar Borges 08 December 2016 (has links)
Este estudo in vitro avaliou a influência do tempo de aplicação do bicarbonato de sódio a 10% na qualidade da união de um sistema adesivo universal unido ao esmalte bovino clareado por meio de testes de resistência de união (microtração imediata e após 6 meses) e grau de conversão na interface adesiva (espectroscopia micro-Raman). Cento e dez blocos de esmalte bovino (4x4 mm) foram planificados e distribuídos aleatoriamente em 5 grupos: C: controle, sem clareamento; B: clareamento com peróxido de hidrogênio 35% (HP); BS3: clareamento com HP seguido de tratamento com a solução de bicarbonato de sódio 10% (BS) por 3 min; BS5: clareamento com HP seguido de tratamento com BS por 5 min; BS10: clareamento com HP seguido de tratamento com BS por 10 min. O HP foi aplicado duas vezes (20 minutos cada, com exceção do grupo C) e em seguida as restaurações adesivas foram realizadas. Após 24 horas, 20 espécimes de cada grupo foram seccionados em palitos (1x1 mm) e submetidos ao teste de resistência de união (imediato e após 6 meses) em máquina de ensaios universal com velocidade de 0,5 mm/min (n=10). Os dados foram analisados por ANOVA a dois critérios (p <0,05). As médias das análises imediata e após 6 meses foram: C: 26,77 / 25,32; B: 26,42 / 26,42; BS3: 23,95 / 22,98; BS5: 23,65 / 26,64; BS10: 23,42 / 29,30. Nenhum dos fatores testados apresentou significância: tratamento (p=0,349) e tempo (p=0,234), não havendo interação entre estes (p=0,198). Falhas adesivas foram predominantes nos dois períodos de avaliação. Para a análise do grau de conversão, após 24 horas da restauração, 2 espécimes de cada grupo foram seccionados em fatias de 1mm, sendo apenas 3 fatias selecionadas. Os seguintes parâmetros foram utilizados: excitação dos espécimes com laser de argônio operando a 538 nm, espectro obtido a uma resolução ~4cm-1, sob uma região de espectro entre 1580-1660cm-1, verificando a altura dos picos 1608cm-1 e 1637cm-1. Os dados foram analisados por ANOVA a um critério (p <0,05) e as médias do grau de conversão foram: C: 71,10%; B: 72,11%; BS3: 73,98%; BS5: 69,25%; BS10: 70,56%. O fator de estudo tratamento não apresentou significância estatística (p=0,808). A adesão no esmalte clareado parece não ter sido afetada negativamente quando restaurações adesivas foram feitas imediatamente após o clareamento, independente da aplicação ou não da substância antioxidante. Mais estudos que avaliem a adesão em esmalte clareado, principalmente no que diz respeito ao grau de conversão e aos diferentes tipos de sistemas adesivos universais se fazem necessários para fins comparativos e para que possamos indicar seguramente as restaurações imediatas (quando necessárias) na prática clínica. / The present in vitro study evaluated the influence of the application time of 10% sodium bicarbonate in the adhesion quality of a universal adhesive system bonded to bleached enamel through microtensile bond strength testing (immediate and after 6 months) and the degree conversion (micro-Raman spectroscopy). One hundred and ten bovine enamel blocks (4x4mm) were flattened and randomly allocated into 5 groups: C: control, without bleaching; B: bleached with 35% hydrogen peroxide (HP); BS3: bleached and treated with 10% sodium bicarbonate solution (BS) for 3 min; BS5: bleached and treated with BS for 5 min; BS10: bleached and treated with BS for 10 min. HP was applied twice (20 minutes each, except in group C) and the adhesive restorations were performed. After 24 hours, 20 specimens from each group were sectioned into sticks (1x1 mm) and submitted to microtensile bond strength testing (immediately and after 6 months) in a universal testing machine with a crosshead speed of 0.5 mm/min (n = 10). Data was analyzed by two-way ANOVA (p <0.05). The means of the immediate and 6 months analysis were: C 26.77 / 25.32; B: 26.42 / 26.42; BS3: 23.95 / 22.98; BS5: 23.65 / 26.64; BS10: 23.42 / 29.30. None of the tested factors showed significance: treatment (p = 0.349) and time (p = 0.234), with no interaction between them (p = 0.198). Adhesive failures were predominant in both evaluation periods. For the degree of conversion analysis, 2 specimens of each group were sectioned into 1 mm slices after 24 hours of the restorative procedure, and 3 slices were selected. The following parameters were used: excitation of specimens with argon laser operating at 538 nm, spectrum obtained at a resolution of ~4cm-1, under a spectrum region between 1580-1660cm-1, evaluating the height of the peaks at 1608cm-1 and 1637cm-1. Data was analyzed by one-way ANOVA (p <0.05). The means of degree of conversion were: C: 71.10%; B: 72.11%; BS3: 73.98%; BS5: 69.25%; BS10: 70.56%. The study factor \"treatment\" was not statistically significant (p = 0.808). The results of bonding to bleached enamel was not negatively affected when adhesive restorations were made immediately after bleaching, regardless of the application of the antioxidant substance. Further studies to evaluate the adhesion on bleached enamel, mainly with regard to the degree of conversion and different types of universal adhesive systems are needed for comparative purposes. Only after this, the immediate restoration (if necessary) in clinical practice can be safely and indicated.
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Cristallisation du bicarbonate de sodium : étude pratique et théorique / Sodium bicarbonate crystallization : theoretical and practical study

Gérard, Antoine 18 June 2014 (has links)
Récemment, il y a une demande accrue pour des cristaux de bicarbonate de sodium de propriétés d'usage spécifiques. Dans l'étude présentée, la réaction de cristallisation du bicarbonate de sodium est abordée et s'effectue dans un milieu triphasique dans lequel interviennent de nombreux phénomènes tels que le transfert de matière, la nucléation et la croissance cristalline. L'objectif de ce travail est d'étudier l'impact des paramètres opératoires, des additifs et de la technologie du réacteur sur la cristallisation du bicarbonate de sodium afin d'obtenir des cristaux avec une taille importante et une masse volumique apparente non tassée élevée. Les essais réalisés dans un réacteur ouvert de type MSMPR (Mixed Suspension Mixed Product Removal) ont permis d'optimiser les conditions opératoires du procédé et ont montré que l'ajout de calcium par le biais d'une solution de chlorure de calcium dans le milieu réactionnel améliore sensiblement la morphologie des cristaux, réduit la vitesse de nucléation tout en influençant légèrement la vitesse de croissance cristalline. Lorsque du polystyrène sulfonate de sodium (NaPSS) est ajouté au chlorure de calcium, sont obtenus des cristaux encore plus compacts avec des surfaces plus lisses et des arêtes marquées. A contrario, l'utilisation d'additifs chelatant le calcium comme le citrate de calcium dégrade la qualité des cristaux de bicarbonate de sodium et est donc proscrite pour une utilisation industrielle car les étapes de filtration et de séchage sont plus difficiles. Enfin, le passage d'un réacteur MSMPR à un réacteur à lit fluidisé a conduit, dans des conditions opératoires identiques, à une amélioration notable de la qualité du produit fini en produisant des cristaux avec une morphologie relativement sphérique et une taille importante / Recently, there is an increased demand for sodium bicarbonate crystals with specific properties. In the present study, the crystallization reaction of sodium bicarbonate is performed in a three-phase medium in which many phenomena such as mass transfer, nucleation and crystal growth occurred. The objective of this work is to study the impact of operating parameters, additives and reactor technology on the crystallization of sodium bicarbonate in order to obtain crystals with important size and high bulk density. The experiments carried out in a MSMPR (Mixed Suspension Mixed Product Removal) reactor have shown that the addition of calcium through a calcium chloride solution in the reaction mixture improves the crystal morphology, reduces the nucleation rate and weakly influences the crystal growth rate. When a mixture of sodium polystyrene sulfonate (NaPSS) and calcium chloride is used, more compact crystals with smoother surfaces and marked edges are obtained. Conversely, the use of calcium chelating additives such as calcium citrate affects the quality of sodium bicarbonate crystals and thus is prohibited for industrial use because the filtration and drying steps are much more difficult. Finally, the transposition from a MSMPR reactor to a fluidized bed reactor allows, under the same operating conditions, a significant improvement of the solid quality by producing big spheroidal particles
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The Effects of a Combined Supplementation of Creatine and Sodium Bicarbonate on Repeated Sprint Performance

Barber, James Jeremy, Hagobian, Todd, McGaughey, Karen, McDermott, Ann Yelmokas, Olmstead, Jennifer Davis 01 September 2010 (has links) (PDF)
Abstract The Effects of a Combined Supplementation of Creatine and Sodium Bicarbonate on Repeated Sprint Performance James Jeremy Barber There is well-established research that suggests both creatine and sodium bicarbonate are effective ergogenic aids. However, only one published study has examined the combined effects of creatine and sodium bicarbonate. The primary purpose of this study was to determine if a combined supplementation of creatine monohydrate and sodium bicarbonate would further enhance the well-documented effects of creatine supplementation alone on repeated sprint performance. Thirteen healthy and fit males (Mean age = 21.15 ± 0.65 years and mean VO2 max = 66.72 ± 5.78) participated in this experimental study using a double-blinded crossover study design in which each subject was used as his own control. All subjects completed 3 conditions, followed by a 3-week washout period between each condition: 1) Placebo (Pl; 5 g maltodextrin + 0.5 g/kg maltodextrin), 2) Creatine (Cr; 5 g + 0.5 g/kg maltodextrin), and 3) Creatine plus sodium bicarbonate (Cr+Sb; 5g + 0.5 g/kg sodium bicarbonate). Each condition was a 2-day supplementation. In the morning after each supplementation, peak power, RPP, mean power, RMP, fatigue index, and perceptions of fatigue and GI distress were assessed during six 10-second repeated Wingate tests. Blood bicarbonate, pH, and lactate were measured 5 minutes before testing and immediately after the last Wingate sprint. The main findings were; 1) Cr+Sb produced 7% greater relative peak power and 4.6% greater peak power values than placebo, and 2) Cr+Sb demonstrated the greatest attenuation of decline in relative peak power over six repeated sprints. However, in contrast to our hypotheses, no benefits from either supplementation were observed for relative mean power, fatigue index, and perception of fatigue. Considering that this current study found benefits from combining creatine and sodium bicarbonate, it suggests that combining the supplements may improve repeated sprint performance. Future research on a greater sample size, a specific athletic population, various exercise modes, and comparing results with a sodium bicarbonate alone supplementation would be beneficial in determining if this combined supplementation is worthwhile.
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The Effects of 8 Weeks of Low Dose Supplementation of Creatine and Sodium Bicarbonate on Exercise Performance

Morris, Amanda Jessica 01 December 2013 (has links) (PDF)
Short-term (3-7 days), high doses of creatine (20g/d) and/or sodium bicarbonate (0.5g/kg body weight) supplementation increase exercise performance during short term high intensity activities; however, it remains unclear whether long-term, low doses of these supplements have a positive impact on exercise performance. The purpose of this study was to determine the effects of long-term (8 weeks), low dose creatine supplementation on exercise performance, and whether combining creatine and sodium bicarbonate supplementation has an additive effect. Sixty-three healthy, habitually active, adults (28 M, 35 W; 22+2 years; 23+ 3 BMI) were randomly assigned by sex to one of three supplement groups: placebo (PL), creatine only (3g/day; Cr), or creatine plus sodium bicarbonate (3g creatine plus 1g sodium bicarbonate; Cr+Sb) for 8 weeks. Before and after supplementation subjects completed two exercise performance tests on separate days. Subjects completed repeated Wingate sprint tests (6 x 10 second sprints) and changes in the slope across the 6 sprints (rate of decline) was analyzed between groups. We also collected 5 km time-trial and the data were analyzed using repeated measures ANOVA. In the repeated sprint test, peak power output slope was significantly decreased (P=0.04) in PL (-83%) and Cr+Sb (-82%) but did not change in Cr alone and was significantly better (P=0.03) than Pl and Cr+Sb. Similarly, mean power output slope significantly decreased (P0.05) in time to completion. However, Cr alone significantly improved time to completion (-3%; P=0.01). Taken together, these data suggest that long-term, low dose creatine supplementation increases exercise performance but adding sodium bicarbonate supplementation has no beneficial impact on exercise performance.
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Investigation of the Chemical Pathway for Gaseous Nitrogen Dioxide Formation during Flue Gas Desulfurization with Dry Sodium Bicarbonate Injection

Stein, Antoinette Weil January 2001 (has links)
No description available.
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Kortsiktiga effekter avbikarbonatbehandling pålungmossa i plantskola / Short term effects on liverwort treated with sodiumbicarbonate

Stenström, Manne January 2022 (has links)
Årligen producerar svenska skogsplantskolor runt 400 miljoner plantor till skogsbruket.Lungmossan är ett av de stora ogräsen för de skogliga plantskolorna. Lungmossan breder utsig på plantbäddarna och omöjliggör hanteringen av plantorna. Idag finns det inget tillåtetbekämpningsmedel för att bekämpa lungmossa på marknaden. Behandling av bikarbonat i fastform har visat goda resultat men är svåra att genomföra i stor skala. I detta arbete harmöjligheten att bekämpa lungmossa med vattenlöslig bikarbonatbehandling studerats.Ett plantskoleförsök genomfördes i ett av Skogforsks växthus i Sävar. Försöket bestod av tvåförstudier och sedan ett huvudförsök med 9 olika försöksuppställningar. Totalt ingick 49Starpot 50 kassetter med 24–48 granplantor i varje. Resultatet visade att det går att behandlalungmossa med bikarbonat utblandat med vatten kortsiktigt, men att de skadorna som uppstårunder behandling på granplantorna gör metoden irrelevant. I stället bör vidare studier påbikarbonat i fast form undersökas.

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