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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.
81

Tampões e antioxidantes na qualidade do sêmen de pôneis / Buffers and antioxidants in the semen quality of pony stallions

Trentin, Janislene Mach January 2018 (has links)
A inseminação artificial é utilizada como uma importante ferramenta para o melhoramento reprodutivo, tanto com sêmen resfriado ou congelado. O primeiro experimento teve como objetivo identificar um tampão de pH para resfriamento de sêmen de pôneis por 48 horas a 5°C e 15°C. O efeito de cinco tampões (TES (ácido N-tris (hidroximetil) metil-2-aminoetanosulfônico), PIPES (ácido piperaxín-N,N'-bis(2-etanosulfônico)), BES (ácido N,N-Bis(2-18hidroxietil)-2-aminoetanosulfônico), MES (ácido 4-morfolinoetanosulfônico) e HEPES (ácido N-2-hidroxietilpiperazina-N’-2-etanosulfônico)) foi avaliado em um diluente composto de leite em pó desnatado e glicose. Os testes do diluente com os tampões BES, MES e TES foram conduzidos com o sêmen fresco de oito pôneis e no sêmen resfriado por 48 h a 15°C. Uma amostra de cada grupo foi utilizada para análise da motilidade, pH, osmolaridade, teste hiposmótico, atividade mitocondrial (MTT) e integridade de membrana através das sondas fluorescentes. O pH e a osmolaridade dos diluentes sem o sêmen também foram avaliados. Os dados foram analisados por análise de variância e pelo teste de Tukey, quando P < 0.05 foi significante. A osmolaridade do sêmen diluído não variou entre diluentes e foi para o BES 350.91 ± 11.24 mOsm, MES 350.41 ± 11.76 mOsm e TES 350 ± 12.96 mOsm. O pH do sêmen após diluição nos respectivos diluentes variou entre as horas avaliadas (P < 0.05) e não variou com o passar do tempo o que evidencia o efeito tamponante dos diluentes. A osmolaridade dos diluentes foi similar entre os tampões BES (366 ± 5.47 mOsm), MES (370 ± 6.12 mOsm) ou TES (371 ± 5.47 mOsm) a fresco e sem adição de sêmen. Já o pH variou (P < 0.05) de acordo com o tampão. No experimento a 5°C ocorreu decréscimo na porcentagem de motilidade total, progressiva e local do sêmen resfriado após 24 h e 48 h comparado a avaliação a fresco em todos os grupos. No entanto, a porcentagem de espermatozoides móveis a fresco, 24 h e 48 h a 5°C entre tratamentos foi similar. A porcentagem de espermatozoides reativos ao teste hiposmótico, e com atividade mitocondrial não diferiu entre tratamentos. No experimento a 15°C o vigor e motilidade total, progressiva e local foram similares entre os tampões BES, MES e TES em cada período avaliado. A osmolaridade do sêmen diluído não variou entre diluentes e foi para o BES 360.93 ± 10.52 mOsm, MES 361.47 ± 6.79 mOsm e TES 361.56 ± 7.68 mOsm. Devido as características individuais de cada tampão o pH do sêmen diluído variou entre os diluentes com os tampões utilizados. A porcentagem de espermatozoides reativos ao teste hiposmótico, com atividade mitocondrial e membrana intacta observada com CFDA e PI não diferiu entre tratamentos. Evidenciou-se que tanto BES, MES ou TES podem ser utilizados no armazenamento e transporte do sêmen de pôneis durante 48 h a 5°C ou 15°C. O segundo experimento teve como objetivo foi avaliar a influência da suplementação de ácidos graxos poli-insaturados sobre a qualidade de sêmen de pôneis da raça Brasileira a fresco e após congelamento. Oito pôneis receberam sua dieta convencional não suplementada (grupo controle) ou dieta convencional e 70 g de farinha de alga Schizochytrium sp rica em DHA (grupo PUFA). O efeito da Vitamina E (1 mM, DL-α-tocoferol), adicionada ao diluente de congelamento para sêmen também foi avaliado sobre a qualidade seminal, antes e após o congelamento do sêmen. O sêmen foi coletado a cada 15 dias durante 60 dias. Os garanhões tratados passaram a controle e vice-versa após um intervalo de sessenta dias. O sêmen foi avaliado a fresco e após o congelamento. Motilidade e vigor foram avaliados a fresco. Após o descongelamento motilidade, funcionalidade de membrana, integridade de membrana e análise computadorizada da motilidade foram avaliados. Os valores médios para os parâmetros avaliados a fresco no grupo PUFA e controle foram similares. Os valores médios da motilidade total, progressiva e local, hiposmótico, CFDA/PI e análise computadorizada de sêmen suplementados com DHA e o grupo controle pós-descongelamento não diferiram. A associação da suplementação de DHA e Vitamina E adicionada ao diluente não potencializou a capacidade antioxidante do diluente durante o congelamento. A associação da suplementação de DHA e Vitamina E adicionada ao diluente resultou em diminuição da motilidade total e progressiva comparada ao grupo não suplementado (controle). A suplementação de 70 g de farinha de alga Schizochytrium sp rica em DHA e ou a inclusão de 1 mM de vitamina E ao diluente de congelamento de sêmen em pôneis da raça Brasileira não foi eficiente para promover melhoria na viabilidade seminal após a coleta ou mesmo após o congelamento. / Artificial insemination with cooled and frozen semen is an important tool for breeding industry. The first experiment aimed to identify a pH buffer for cooling semen of ponies for 48 h at 5°C and 15°C. The effect of five buffers (TES (N-tris (hydroxymethyl) methyl-2-aminoethanesulfonic acid), PIPES (piperaxin-N, N'-bis (2-ethanesulfonic acid)), BES (N, N-Bis (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid)) was evaluated in a extender composed of skimm milk powder and glucose. Analysis with the BES, MES and TES buffers were performed in fresh semen of eight ponies and in cooled semen for 48 h at 15°C. A sample from each group was used for analysis of motility, pH, osmolarity, hyposmotic test, mitochondrial activity (MTT) and membrane integrity through fluorescent probes. The pH and osmolarity of the extenders without semen were also evaluated. Data were assessed by analysis of variance and Tukey's test, when P <0.05 was considered significant. Osmolarity of the diluted semen did not differ between extenders and was for BES 350.91 ± 11.24 mOsm, MES 350.41 ± 11.76 mOsm and TES 350 ± 12.96 mOsm. The pH of the semen after dilution in the respective extenders varied between the hours (P <0.05) and did not change over time as evidenced by the buffering effect of the extenders. Extender osmolarity was similar between BES (366 ± 5.47 mOsm), MES (370 ± 6.12 mOsm) or TES (371 ± 5.47 mOsm) buffers after dilution and without addition of semen. The pH varied (P <0.05) according to the buffer. In the experiment at 5°C all treatments showed a decrease in the percentage of total, progressive and local motility of the cooled semen after 24 h and 48 h compared to the fresh. However, in the percentage of motile sperm to fresh, 24 h and 48 h at 5°C between treatments was similar. Percentage of spermatozoa reactive to the hyposmotic test, and with mitochondrial activity did not differ between treatments. In the experiment at 15°C total, progressive and local vigor and motility were similar between BES, MES and TES buffers in each period. Osmolarity of the diluted semen did not differ between extenders and was for BES 360.93 ± 10.52 mOsm, MES 361.47 ± 6.79 mOsm and TES 361.56 ± 7.68 mOsm. Due to the individual characteristics of each buffer, diluted semen pH varied between the extenders with the buffers used. Percentage of spermatozoa reactive to the hyposmotic test, with mitochondrial activity and intact membrane observed with CFDA and PI did not differ between treatments. We concluded that BES, MES or TES can be used in the storage and transport of ponies semen for 48 h at 5°C or 15°C. The second experiment aimed to evaluate the influence of polyunsaturated fatty acid supplementation in the fresh and after freezing semen of Brazilian ponies. Eight ponies received their conventional diet (control group) or conventional diet and 70 g of DHA-rich Schizochytrium sp algae meal (PUFA group). The effect of Vitamin E (1 mM, DL-α-tocopherol) added to the freezing diluent for semen was also evaluated on seminal quality, before and after freezing. Semen was collected every 15 days during 60 days. Stallions were reversed in treatments after an interval of sixty days. Semen was evaluated fresh and after freezing. Motility and vigor were estimated in the fresh semen. After thawing motility, membrane functionality, membrane integrity and computed motility analysis were evaluated. Mean values for fresh parameters evaluated in the PUFA and control groups were similar. Mean values of total, progressive and local motility, hyposmotic, CFDA/PI and computerized analysis of semen supplemented with DHA and post-thaw control group did not differ. The combination of DHA and Vitamin E supplementation added to the diluent did not potentiate the antioxidant capacity of the diluent during freezing and resulted in decreased total and progressive motility compared to the non-supplemented group. Supplementation of 70 g of DHA-rich microalgae Schizochytrium sp and the addition of 1 mM vitamin E to the semen freezing diluent in Brazilian ponies was not efficient to promote improvement in seminal viability after collection or even after freezing.
82

Ovlivnění plazmatické hladiny cholesterolu modelového organizmu polynenasycenými mastnými kyselinami n-3

Čeganová, Markéta January 2014 (has links)
The aim of this thesis is to assess the influence of the polyunsaturated fatty acids, especially DHA and EPA in the diet on the animal organism in accordance to the levels of total HDL and LDL cholesterol and triglycerides in plasma. As experimental animals were used rats and they were divided into 3 groups of 10 pieces: control group with the addition of 6 % Carthamus tinctorius (n-6 flares), the group with the addition of 6 % fish oil (n-3: EPA, DHA fish) and the group with 6 % addition of oil from Schizochytrium (n-3: DHA, DHA). After 40 days the animals were putted to death according to relevant regulations. Blood lipids were obtained from blood samples by spectrophotometry. Value of polyunsaturated fatty acids of n-3 and n-6 was set by gas chromatography in the liver, muscle and adipose tissue. In accordance to the increase of content n-3 PUFA in group with fish oil and with oil from Schizochytrium, total and LDL cholesterol was reduced in comparison of samples in control group. In comparison to the control group were TAG reduced only in the group with addition of oil.
83

Efekt polynenasycených mastných kyselin n-3 ve výživě potkana na expresi vybraného genu

Zamazalová, Nikola January 2015 (has links)
The aim of my thesis on topic The effect of n-3 polyunsaturated fatty acids in the diet of rats on expression of selected genes was to investigate the effect of eicosapentaenoic acid (EPA) and docosapentaenoic acid (DHA) on the expression of genes which encode GPR120, AdipoR1 and AdipoR2 receptors in relation to suppress low-grade chronic inflammation in organism to reduce the risk of atherosclerosis by dietary intervention in rats. Rats were fed by a mixture MYPO with 6 % safflower oil (diet S), 6 % fish oil (diet F) or 6 % of oil from algae Schizochytrium (diet A). Gene expression was measured by quantitative real-time PCR method and the results were evaluated by using the software qbase + (Biogazelle NV). Relative expression of GPR120 gene was in F diet 88 % (P > 0,05), in A diet 93 % (P > 0,05) in comparison with control group (100 %). Relative expression of ADIPOR1 gene was in F diets and A diet 82 % (P < 0,05) in comparison with the control group. For ADIPOR2 gene relative expression was 71 % (P < 0,05) in diet F and 68 % (P < 0,05) in diet A. The results were contrary to our hypothesis. However, they exactly match the results of other studies in the available literature. It would be appropriate to carry out further studies on this issue.
84

Avaliação da composição de ácidos graxos de peixes de água doce / Evaluation of fatty acid composition of fresh water fish

Castro, Fátima Aparecida Ferreira de 25 April 2003 (has links)
Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2016-10-21T17:30:39Z No. of bitstreams: 1 texto completo.pdf: 514500 bytes, checksum: de271ef0f6d6dddb183f81a3816210da (MD5) / Made available in DSpace on 2016-10-21T17:30:39Z (GMT). No. of bitstreams: 1 texto completo.pdf: 514500 bytes, checksum: de271ef0f6d6dddb183f81a3816210da (MD5) Previous issue date: 2003-04-25 / Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Foram determinadas as composições dos ácidos graxos de três peixes de água doce (tilápia do Nilo - Oreochromis niloticus; carpa comum - Cyprinus carpio e híbrido tambacu: tambaqui - Colossoma macropomum e pacu - Piaractus mesopotamicus). Os peixes foram avaliados na forma crua, assada e cozida à vapor, com pele e sem pele, nos tempos 0, 15, 30 e 45 dias de armazenamento sob congelamento. Os lipídios foram extraídos pelo método de Folch et al. (1957), esterificados pelo método Hartman e Lago (1973) e analisados por cromatografia gasosa (CG). Os ácidos palmítico (16:0) e oléico (18:1) foram os ácidos graxos presentes em maior proporção nos peixes estudados, considerando-se os tempos de estocagem e os modos de cocção. Foram verificados altos percentuais de ácidos graxos saturados (em média, 43,3 e 37,4%) para tilápia e tambacu, respectivamente) e monoinsaturados (em média 53,8%) para carpa. Os ácidos graxos polinsaturados foram encontrados em menor percentual (em média 17,5%) para tilápia. De maneira geral, a composição de ácidos graxos dos três peixes avaliados não apresentaram grandes variações em função do tempo de congelamento e do modo de preparo. Por outro lado, os percentuais dos ácidos graxos aumentaram com a retirada da pele, em todos os tempos de estocagem sob congelamento e modos de cocção. Os maiores percentuais de ácidos graxos polinsaturados foram encontrados na carpa assada, com e sem pele (23,3 a 27,3%); na tilápia cozida à vapor, com e sem pele (26,2 a 35,1%) e no tambacu cozido à vapor, com e sem pele (27,1 a 35,5%) após 45 dias de estocagem sob congelamento, indicando que a cocção e o congelamento exerceram um efeito positivo sobre o percentual deste grupo de ácidos graxos, de grande importância para a saúde humana. Os maiores percentuais de DHA e EPA foram encontrados nos peixes submetidos à cocção (úmida e seca), indicando que os métodos de cocção utilizados tiveram efeito positivo sobre os principais ácidos graxos polinsaturados da série ω-3. Concluiu-se que, dentre os peixes estudados, a tilápia, apesar do menor percentual de ácidos graxos polinsaturados encontrado, mostrou-se a mais promissora para a prescrição de dietas que requerem baixo teor de lipídios (0,79%), além de uma relação mais elevada entre os ácidos graxos da série ω-3/ω-6 (0,84). / The fatty acid composition of three fresh water fishes was determinated (Nile tilapia - Oreochromis niloticus; common carp - Cyprinus carpio and the hybrid tambacu: tambaqui - Colossoma macropomum with pacu - Piaractus mesopotamicus). Raw, steamed and roasted fishes were evaluated with or without skin at 0, 15, 30 and 45 days of freezing storage. The lipids were extracted by the method of Folch et al. (1957). Then, they were sterified by the method of Hartman and Lago (1973) and further analysed by gas chromatography (GC). Palmitic (16:0) and oleic (18:1) acids were found in the highest proportion in the fishes studied, irrespective to the cooking processes and the storage time. High levels of saturated fatty acids were found for tilapia and tambacu (43.3 and 37.4% on average, respectively) and monounsaturated fatty acids for carp (53.8% on average). Tilapia showed the lowest levels of polyunsaturated fatty acids - PUFA (17.5% on average). In general, the fish fatty acid composition did not change considerably due to either the cooking process or the freezing storage time. On the other hand, the fatty acid content increased with the skin removal, regardless to the cooking or the storage process. PUFA were found in higher concentrations in roasted carp (23.3 to 27.3%); steamed tilapia (26.2 to 35.1%) and in steamed tambacu (27.1 to 35.5%), with or without skin, after 45 days of freezing storage. This indicates that cooking and freezing improve the levels of PUFA, which are considered to exert a beneficial effect on human health. The higher levels of DHA and EPA were found in processed fishes (roasted or steamed), which suggests the positive effect of cooking in ω-3 PUFA. Among the fishes analysed, tilapia, although have shown the lowest PUFA level, seems to be the most promessing fish for low-fat diet prescription (0.79%), with the highest ω-3/ω-6 ratio (0.84). / Não foi localizado o cpf do autor.
85

Digital hydraulics in aircraft control surface actuation : Modelling and evaluation of digital hydraulic systems with focus on performance and energy efficiency

Ward, Simon January 2017 (has links)
The purpose of this thesis has been to compare and analyse the use of digital hydraulic actuators in place of traditional actuators in aircraft control surface manipulation. Digital hydraulic actuator referring to a hydraulic actuator where the power has been discretized using discrete on/off-valves. For this purpose three simulation models have been used. The first model consists of a benchmark model, designed to represent a digital hydraulic actuator acting on a mass under the influence of an external spring load. The discretization in this case comes from the fact that three separate pressure levels have been used to power a four-chambered tandem piston, resulting in 81 possible force combinations.The second simulation model represents a 6 degrees of freedom aircraft model parametrised to behave like a F16 fighter aircraft. The purpose of this model has been to serve as a means to implement the digital actuator in an aircraft. The third model has been heavily based on the F16 model but re-parametrised such that it represents a delta canard aircraft. The actuators in the aircraft models was initially mounted on the control surface primarily dedicated for the manoeuvre which was simulated, in this case a step in altitude, meaning that the control surface was the elevon.As it would turn out the digital actuator had trouble achieving the precision required in order to adequately fly the aircraft at a low enough energy consumption. As such the idea took form to implement a hybrid design where the digital actuator would be paired with a proportional actuator on a separate control surface, flaperons. The digital actuator would then only require to be positioned in a close enough position and once there lock in place, leaving the proportional actuator to handle the fine tuning and trim of the aircraft. It would appear that by using the hybrid actuator design the energy consumption during the right circumstances could be reduced by as much as 40% for the delta canard configuration and 30% for the F16 case.
86

Tampões e antioxidantes na qualidade do sêmen de pôneis / Buffers and antioxidants in the semen quality of pony stallions

Trentin, Janislene Mach January 2018 (has links)
A inseminação artificial é utilizada como uma importante ferramenta para o melhoramento reprodutivo, tanto com sêmen resfriado ou congelado. O primeiro experimento teve como objetivo identificar um tampão de pH para resfriamento de sêmen de pôneis por 48 horas a 5°C e 15°C. O efeito de cinco tampões (TES (ácido N-tris (hidroximetil) metil-2-aminoetanosulfônico), PIPES (ácido piperaxín-N,N'-bis(2-etanosulfônico)), BES (ácido N,N-Bis(2-18hidroxietil)-2-aminoetanosulfônico), MES (ácido 4-morfolinoetanosulfônico) e HEPES (ácido N-2-hidroxietilpiperazina-N’-2-etanosulfônico)) foi avaliado em um diluente composto de leite em pó desnatado e glicose. Os testes do diluente com os tampões BES, MES e TES foram conduzidos com o sêmen fresco de oito pôneis e no sêmen resfriado por 48 h a 15°C. Uma amostra de cada grupo foi utilizada para análise da motilidade, pH, osmolaridade, teste hiposmótico, atividade mitocondrial (MTT) e integridade de membrana através das sondas fluorescentes. O pH e a osmolaridade dos diluentes sem o sêmen também foram avaliados. Os dados foram analisados por análise de variância e pelo teste de Tukey, quando P < 0.05 foi significante. A osmolaridade do sêmen diluído não variou entre diluentes e foi para o BES 350.91 ± 11.24 mOsm, MES 350.41 ± 11.76 mOsm e TES 350 ± 12.96 mOsm. O pH do sêmen após diluição nos respectivos diluentes variou entre as horas avaliadas (P < 0.05) e não variou com o passar do tempo o que evidencia o efeito tamponante dos diluentes. A osmolaridade dos diluentes foi similar entre os tampões BES (366 ± 5.47 mOsm), MES (370 ± 6.12 mOsm) ou TES (371 ± 5.47 mOsm) a fresco e sem adição de sêmen. Já o pH variou (P < 0.05) de acordo com o tampão. No experimento a 5°C ocorreu decréscimo na porcentagem de motilidade total, progressiva e local do sêmen resfriado após 24 h e 48 h comparado a avaliação a fresco em todos os grupos. No entanto, a porcentagem de espermatozoides móveis a fresco, 24 h e 48 h a 5°C entre tratamentos foi similar. A porcentagem de espermatozoides reativos ao teste hiposmótico, e com atividade mitocondrial não diferiu entre tratamentos. No experimento a 15°C o vigor e motilidade total, progressiva e local foram similares entre os tampões BES, MES e TES em cada período avaliado. A osmolaridade do sêmen diluído não variou entre diluentes e foi para o BES 360.93 ± 10.52 mOsm, MES 361.47 ± 6.79 mOsm e TES 361.56 ± 7.68 mOsm. Devido as características individuais de cada tampão o pH do sêmen diluído variou entre os diluentes com os tampões utilizados. A porcentagem de espermatozoides reativos ao teste hiposmótico, com atividade mitocondrial e membrana intacta observada com CFDA e PI não diferiu entre tratamentos. Evidenciou-se que tanto BES, MES ou TES podem ser utilizados no armazenamento e transporte do sêmen de pôneis durante 48 h a 5°C ou 15°C. O segundo experimento teve como objetivo foi avaliar a influência da suplementação de ácidos graxos poli-insaturados sobre a qualidade de sêmen de pôneis da raça Brasileira a fresco e após congelamento. Oito pôneis receberam sua dieta convencional não suplementada (grupo controle) ou dieta convencional e 70 g de farinha de alga Schizochytrium sp rica em DHA (grupo PUFA). O efeito da Vitamina E (1 mM, DL-α-tocoferol), adicionada ao diluente de congelamento para sêmen também foi avaliado sobre a qualidade seminal, antes e após o congelamento do sêmen. O sêmen foi coletado a cada 15 dias durante 60 dias. Os garanhões tratados passaram a controle e vice-versa após um intervalo de sessenta dias. O sêmen foi avaliado a fresco e após o congelamento. Motilidade e vigor foram avaliados a fresco. Após o descongelamento motilidade, funcionalidade de membrana, integridade de membrana e análise computadorizada da motilidade foram avaliados. Os valores médios para os parâmetros avaliados a fresco no grupo PUFA e controle foram similares. Os valores médios da motilidade total, progressiva e local, hiposmótico, CFDA/PI e análise computadorizada de sêmen suplementados com DHA e o grupo controle pós-descongelamento não diferiram. A associação da suplementação de DHA e Vitamina E adicionada ao diluente não potencializou a capacidade antioxidante do diluente durante o congelamento. A associação da suplementação de DHA e Vitamina E adicionada ao diluente resultou em diminuição da motilidade total e progressiva comparada ao grupo não suplementado (controle). A suplementação de 70 g de farinha de alga Schizochytrium sp rica em DHA e ou a inclusão de 1 mM de vitamina E ao diluente de congelamento de sêmen em pôneis da raça Brasileira não foi eficiente para promover melhoria na viabilidade seminal após a coleta ou mesmo após o congelamento. / Artificial insemination with cooled and frozen semen is an important tool for breeding industry. The first experiment aimed to identify a pH buffer for cooling semen of ponies for 48 h at 5°C and 15°C. The effect of five buffers (TES (N-tris (hydroxymethyl) methyl-2-aminoethanesulfonic acid), PIPES (piperaxin-N, N'-bis (2-ethanesulfonic acid)), BES (N, N-Bis (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid)) was evaluated in a extender composed of skimm milk powder and glucose. Analysis with the BES, MES and TES buffers were performed in fresh semen of eight ponies and in cooled semen for 48 h at 15°C. A sample from each group was used for analysis of motility, pH, osmolarity, hyposmotic test, mitochondrial activity (MTT) and membrane integrity through fluorescent probes. The pH and osmolarity of the extenders without semen were also evaluated. Data were assessed by analysis of variance and Tukey's test, when P <0.05 was considered significant. Osmolarity of the diluted semen did not differ between extenders and was for BES 350.91 ± 11.24 mOsm, MES 350.41 ± 11.76 mOsm and TES 350 ± 12.96 mOsm. The pH of the semen after dilution in the respective extenders varied between the hours (P <0.05) and did not change over time as evidenced by the buffering effect of the extenders. Extender osmolarity was similar between BES (366 ± 5.47 mOsm), MES (370 ± 6.12 mOsm) or TES (371 ± 5.47 mOsm) buffers after dilution and without addition of semen. The pH varied (P <0.05) according to the buffer. In the experiment at 5°C all treatments showed a decrease in the percentage of total, progressive and local motility of the cooled semen after 24 h and 48 h compared to the fresh. However, in the percentage of motile sperm to fresh, 24 h and 48 h at 5°C between treatments was similar. Percentage of spermatozoa reactive to the hyposmotic test, and with mitochondrial activity did not differ between treatments. In the experiment at 15°C total, progressive and local vigor and motility were similar between BES, MES and TES buffers in each period. Osmolarity of the diluted semen did not differ between extenders and was for BES 360.93 ± 10.52 mOsm, MES 361.47 ± 6.79 mOsm and TES 361.56 ± 7.68 mOsm. Due to the individual characteristics of each buffer, diluted semen pH varied between the extenders with the buffers used. Percentage of spermatozoa reactive to the hyposmotic test, with mitochondrial activity and intact membrane observed with CFDA and PI did not differ between treatments. We concluded that BES, MES or TES can be used in the storage and transport of ponies semen for 48 h at 5°C or 15°C. The second experiment aimed to evaluate the influence of polyunsaturated fatty acid supplementation in the fresh and after freezing semen of Brazilian ponies. Eight ponies received their conventional diet (control group) or conventional diet and 70 g of DHA-rich Schizochytrium sp algae meal (PUFA group). The effect of Vitamin E (1 mM, DL-α-tocopherol) added to the freezing diluent for semen was also evaluated on seminal quality, before and after freezing. Semen was collected every 15 days during 60 days. Stallions were reversed in treatments after an interval of sixty days. Semen was evaluated fresh and after freezing. Motility and vigor were estimated in the fresh semen. After thawing motility, membrane functionality, membrane integrity and computed motility analysis were evaluated. Mean values for fresh parameters evaluated in the PUFA and control groups were similar. Mean values of total, progressive and local motility, hyposmotic, CFDA/PI and computerized analysis of semen supplemented with DHA and post-thaw control group did not differ. The combination of DHA and Vitamin E supplementation added to the diluent did not potentiate the antioxidant capacity of the diluent during freezing and resulted in decreased total and progressive motility compared to the non-supplemented group. Supplementation of 70 g of DHA-rich microalgae Schizochytrium sp and the addition of 1 mM vitamin E to the semen freezing diluent in Brazilian ponies was not efficient to promote improvement in seminal viability after collection or even after freezing.
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Fatores psicossocias relacionados à manutenção da abstinência alcoólica no pós-transplante hepático / Psychosocial factors related to maintenance of alcohol abstinence after hepatic transplantation

Rocha, Heidmilene Gonçalves 02 August 2017 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Psicologia, Programa de Pós-graduação em Psicologia Clínica e Cultura, 2017. / Submitted by Raquel Almeida (raquel.df13@gmail.com) on 2017-10-24T18:46:36Z No. of bitstreams: 1 2017_HeidmileneGonçalvesRocha.pdf: 1798164 bytes, checksum: 2698c43af6f52acbec266307f0b22c2c (MD5) / Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2017-11-03T16:48:59Z (GMT) No. of bitstreams: 1 2017_HeidmileneGonçalvesRocha.pdf: 1798164 bytes, checksum: 2698c43af6f52acbec266307f0b22c2c (MD5) / Made available in DSpace on 2017-11-03T16:48:59Z (GMT). No. of bitstreams: 1 2017_HeidmileneGonçalvesRocha.pdf: 1798164 bytes, checksum: 2698c43af6f52acbec266307f0b22c2c (MD5) Previous issue date: 2017-11-03 / O Transplante Hepático (TH) é uma terapêutica que visa substituir parcial ou totalmente o fígado de um doador para um receptor, decorrente de sequelas graves a esse órgão. Dentre as várias indicações para esse tratamento no Brasil, a Doença Hepática Alcoólica (DHA) é a segunda maior, ocasionada pelo uso abusivo e prolongado do álcool. A recaída é uma questão complexa, multifatorial e diz respeito à singularidade de cada pessoa. A avaliação pré- transplante deve seguir diretrizes seguras e contemplar a compreensão global do paciente. O presente estudo teve como objetivo geral identificar fatores protetivos e de risco relacionados à recaída e a não recaída alcoólica no pós-transplante, em pessoas com DHA submetidas a transplantes de fígado, e as variáveis psicológicas associadas às duas condições. O estudo transversal e descritivo, com amostra por conveniência, foi realizado com quinze adultos transplantados de fígado, com média de idade igual a 52,2 anos, 14 do sexo masculino, a maioria casada, com filhos, representando 22% do total de transplantados com DHA de um centro transplantador de Brasília. O método incluiu duas etapas: (a) análise de prontuários, quando foram coletados dados referentes aos pacientes já transplantados com até seis anos de cirurgia prévia, dividindo os participantes triados em dois grupos: recaída (GR) e não recaída (GNR); (b) aplicação de entrevista semiestruturada, da Escala Hospitalar de Ansiedade e Depressão (HADS) e do Inventário de Habilidades de Enfrentamento Antecipatório para Abstinência de Álcool e Outras Drogas (IDHEA-AD), para ambos os grupos. A análise mista, qualitativa e quantitativa, identificou dez participantes no GNR e cinco no GR. Em média, a amostra tinha diagnóstico de cirrose hepática alcoólica há cerca de seis anos, com 28,8 anos de uso de fermentados e destilados, com mais de dez doses por dia, em associação com outras substâncias psicoativas e abstinência alcoólica pré-TH de 3,7 anos. Não houve diferença significativa entre o GR e o GNR nos escores médios de ansiedade, depressão e dos fatores da IDHEA-AD; no entanto, o GR teve média mais baixa na habilidade em assertividade para recusar bebidas e alta em sintomas de ansiedade. De modo geral, ambos os grupos tinham percepções concordantes sobre o uso do álcool antes e após o transplante, com motivações internas para se manterem abstêmios (opinião sobre a bebida e manutenção da saúde) e externas (indicação médica e influência familiar). A família foi descrita como fator de risco (problemas familiares) e de proteção (influência familiar) para a manutenção da abstinência alcoólica pós-transplante. As razões relatadas pelo GR para retomar o uso de álcool foram problemas familiares, a incapacidade laboral, a sensação de bem-estar póstransplante e a influência de terceiros sobre o uso da Substância Psicoativa (SPA). Os participantes referiram satisfação com o tratamento pós-TH e a importância do profissional psicólogo para auxiliar no enfrentamento das questões referentes ao etilismo, ao adoecimento e à recuperação da saúde. O estudo pode aludir ao fato de que homens, com histórico de dependência do álcool, com problemas familiares, baixa habilidade para recusa do álcool, com problemas em relação a atividade laboral pós-operatória e associação de transtornos psiquiátricos em especial ansiedade e depressão tem maiores chances de recaída no uso de álcool após o transplante. O trabalho com essa população deve ser preventivo, contínuo e multiprofissional, com intervenções psicológicas e da equipe baseadas em evidências, especializadas e efetivas nas fases pré e pós-transplante. / Severe sequelae to the liver might be treated by Liver Transplantation (LT), which aims to partially or totally replace it from a donor to a recipient. Alcoholic Liver Disease (ALD) resulting from the chronic alcohol abuse is the second most common indication for this treatment in Brazil. Relapse is a complex, multifactorial and subjective phenomenon. The pre-transplant evaluation should follow safe guidelines and comprehend a global understanding of the patient. The present study aimed to identify protective and risk factors, as well as psychological variables, related to alcohol relapse and non-relapse in people with ALD after liver transplant. This cross-sectional and descriptive study used convenience sample and was performed with fifteen adults, 14 males and 1 female, which have undergone liver transplant, mean age of 52.2 years, mostly married and have children, representing 22% of the total of transplanted patients with ADL in a hepatic transplant center in Brasília. The method included two steps: (a) chart analysis of the transplanted patients who had up to six years from previous surgery, dividing the participants into two groups relapse (GR) and non-relapse (GNR); (b) the use of a semistructured interview for both groups: the Hospital Anxiety and Depression Scale (HADS) and the Inventory of Anticipatory Coping Abstinence Abilities for Alcohol and Other Drugs (IDHEA-AD). The mixed qualitative and quantitative analysis identified ten participants in the GNR and five in the GR. On average, the sample had been diagnosed of alcoholic liver cirrhosis for about six years, with 28.8 years of use of daily fermented and distilled beverages, with more than ten doses per day, in association with other psychoactive substances and alcoholic pre-LT 3.7 years. There was no significant difference between GR and GNR in the mean anxiety, depression and IDHEA-AD scores; however, GR had the lowest mean in the ability to assertiveness to refuse drinks and high in anxiety symptoms. In general, both groups had concurrent perceptions about pre-transplant alcohol use, and internal motivation to maintain abstemiousness (drink opinion, health maintenance) and external motivations (medical indication and family influence). Family was described as a risk factor (family conflicts) and protective factor (good support and functional family dynamics) for the maintenance of posttransplant alcohol withdrawal. The reasons reported by GR to resume alcohol use were family problems, work incapacity, post-transplant well-being and the influence of third parties on the use of Psychoactive substance (PAS). Participants reported satisfaction with post LT treatment and the importance of the professional psychologist to help address issues related to alcoholism, illness, and health recovery. The study may refer to the fact that men with a history of alcohol dependence, family problems, low ability to refuse alcohol, problems with postoperative work activity, and association with psychiatric disorders, especially anxiety and depression, have higher chances of relapse to alcohol use after transplantation. Working with this population require not only preventive, continuous and multiprofessional actions, but also psychological and staff interventions based on evidences and effective and specialized in pre and post-transplantation.
88

Spatiotemporal variability in fatty acid profiles of the copepod Calanus marshallae off the west coast of Vancouver Island

Bevan, Daniel 21 April 2015 (has links)
Factors affecting energy transfer to higher trophic levels can determine the survival and production of commercially important species and thus the success of fisheries management regimes. Juvenile salmon experience particularly high mortality during their early marine residence, but the root causes of this mortality remain uncertain. One potential contributing factor is the food quality encountered at this critical time. The nutritionally vital essential fatty acids (EFA) docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) are essential to all marine heterotrophs, and their availability has the potential to affect energy transfer through a limitation-driven food quality effect. Assessing variability in DHA and EPA in an ecologically important prey species of juvenile salmon could give insight into the prevalence and severity of food quality effects. On the west coast of Vancouver Island (WCVI), one such species is the calanoid copepod Calanus marshallae. This omnivorous species possesses a high grazing capacity and the ability to store large amounts of lipids. As it is also an important prey item for a diverse array of predators, including juvenile Pacific salmon, C. marshallae plays a key role in energy transfer from phytoplankton to high-trophic iv consumers. This study quantified spatiotemporal variability in the quality of C. marshallae as prey for higher trophic levels using three polyunsaturated fatty acid indicators: DHA:EPA, %EFA and PUFA:SFA (polyunsaturated fatty acids to saturated fatty acids). Samples were collected on the WCVI in May and September of 2010 and May 2011. The environmental parameters included in the analysis were the phase of the Pacific Decadal Oscillation (PDO), sea surface temperature (SST), latitude, station depth, and season (spring versus late summer). Despite a phase shift in the PDO from positive to negative, overall means of the fatty acid indicators did not vary between May 2010 and May 2011. Same-station %EFA values rarely fluctuated more than 5%. DHA:EPA ratios were more variable but without a discernable pattern, while PUFA:SFA ratios decreased in shelf stations and increased offshore. Contrary to expectations, fatty acid indicators showed a weak positive correlation or no relationship with SST, nor was there a relationship with latitude. The narrow temperature range observed across all stations suggests that temperature may not play a significant role in PUFA availability off the WCVI. There were, however, significant relationships between the fatty acid indicators and bottom depth and season. Shelf and slope stations showed significantly higher %EFA and PUFA:SFA than did offshore stations (depth >800 m), with this gradient appearing stronger in May than September. While the food quality represented by C. marshallae was consistent across all shelf stations, the lower food quality observed offshore could potentially affect juvenile salmon growth along the WCVI where the shelf narrows to less than 5 km. / Graduate / dpbevan@uvic.ca
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Vision et expression des protéines visuelles du photorécepteur en fonction de la composition alimentaire et de la température du milieu chez le loup de Méditerranée, Dicentrarchus labrax / Vision and expression of the photoreceptor visual proteins according to the food composition and the water temperature of the sea bass, Dicentrarchus labrax

Bouaziz, Mehdi 06 July 2017 (has links)
Cette thèse s'inscrit dans le contexte de mieux comprendre l'effet de la température ainsi que celui de l'acide docosahexaénoïque (DHA) alimentaire dans les performances de vision chez les juvéniles de Dicentrarchus labrax. La rétine est contrainte aux changements de son milieu environnant, incluant les modifications du régime alimentaire et les stress environnementaux comme la température. Par ailleurs, le loup de Méditerranée est une espèce ectotherme, carnivore et pélagique. Son métabolisme, sa physiologie et son comportement dépendent de la température extérieure mais aussi de la composition alimentaire en acides gras et plus spécialement en DHA. Cette étude a rapporté l'impact de l'augmentation (28°C) et de l'abaissement (18°C) de la température du milieu mais aussi l'influence des différentes concentrations de DHA alimentaire sur la composition lipidique ainsi que l'abondance d'ARNm des enzymes clés du métabolisme lipidiques (FADS 2, ELOVL 5, SREBP-1, PLA 2 et la triglycéride lipase) et l'expression des gènes liés à la fonction visuelle (rhodopsine) et à la production de la mélatonine. / This thesis is in the context of more understanding the effect of temperature and different dietary levels of docosahexaenoic acid (DHA) in vision performance of juveniles Dicentrarchus labrax. The retina is constrained by environmental change, including changes in diet and environmental stresses such as temperature. In addition, sea bass is an ectothermic, carnivorous and pelagic species. Their metabolism, physiology and behavior rely on the external temperature but also on the dietary composition of fatty acids and especially DHA. This study reported that the impact of the increase (28°C) and decrease (18°C) of the temperature of the water but also the influence of different dietary DHA concentrations on the lipid composition, abundance of ARNm of key lipid metabolism enzymes (FADS 2, ELOVL 5, SREBP-1, PLA 2 and triglyceride lipase) and the expression of the genes related to the visual function (rhodopsin) and the production of melatonin.
90

Digital hydraulic actuator for flight control

Larsson, Felix, Johansson, Christian January 2019 (has links)
In aviation industry, one of the most important aspects is weight savings. This since with a lowered weight, the performance of the aircraft can be increased together with increased fuel savings and thus lowered running costs. One way of saving weight is to reduce energy consumption, since with lowered energy consumption, lowered mass of fuel is required etc. Most aircraft are today maneuvered with hydraulic systems due to its robustness and power density. It is the primary source of power for primary and secondary flight controls. The control of a conventional system which is using proportional valves is done by altering flow by restricting it to the extent where the desired output is achieved, which implies heat losses since the full performance of its supply is wasted through the valve. In previous research, more energy efficient hydraulic systems called digital hydraulics has been investigated. In difference with conventional hydraulics, digital hydraulics uses low cost, high frequency on/off valves, which either are fully opened, or fully closed, instead of proportional valves to achieve the desired output. With this comes the benefit of no energy losses due to leakage and restriction control. The downsides with digital hydraulics is the controlabillity. One way of controlling it is by using several pressure sources which outputs different pressure levels. By using the on/off valves in different combinations, different outputs can be achieved in a discrete manner. In this thesis, the aim was to remove the impact of the discrete force steps which are present in digital hydraulics by creating concepts with hybrid solutions containing both digital hydraulics and restrictive control. Three concepts were developed and investigated using simulation. The energy consumption and performance was analysed and compared with a reference model, the concepts redundancy compared to conventional systems was discussed and finally the concepts were tested with an aircraft simulation model. The concepts were found to reduce the energy consumption with different magnitude depending on the load cycle. The performance was found to be almost as good as the reference model. The redundancy compared with conventional systems should be possible to maintain with slight modifications, but further investigation is needed. It was found that one of the most important aspects regarding energy consumption is which combination of supply pressures is used to supply the system since it influences leakage and flow due to compression.

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