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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

Efeito da suplementa??o de nitrato diet?tico na forma de uma dose aguda de suco de beterraba na resposta press?rica p?s-exerc?cio em homens com obesidade

Bezerra, ?gnes Denise de Lima 29 November 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-15T13:04:55Z No. of bitstreams: 1 AgnesDeniseDeLimaBezerra_DISSERT.pdf: 2638952 bytes, checksum: 9e4adeece08af0312881a7d9d3a21801 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-19T23:46:02Z (GMT) No. of bitstreams: 1 AgnesDeniseDeLimaBezerra_DISSERT.pdf: 2638952 bytes, checksum: 9e4adeece08af0312881a7d9d3a21801 (MD5) / Made available in DSpace on 2018-02-19T23:46:02Z (GMT). No. of bitstreams: 1 AgnesDeniseDeLimaBezerra_DISSERT.pdf: 2638952 bytes, checksum: 9e4adeece08af0312881a7d9d3a21801 (MD5) Previous issue date: 2017-11-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Sabe-se que a suplementa??o de nitrato pode reduzir a press?o arterial em v?rias popula??es. No entanto, o efeito do suco de beterraba na resposta press?rica p?s-exerc?cio n?o tem sido ainda estudado. O objetivo deste estudo foi verificar o efeito da suplementa??o de nitrato diet?tico, na forma de suco de beterraba, sobre a resposta press?rica p?s-exerc?cio em indiv?duos com obesidade. Em um ensaio cl?nico randomizado do tipo cruzado, 14 homens, normotensos e com obesidade, foram aleatoriamente submetidos a tr?s sess?es experimentais: 1) suco de beterraba com exerc?cio (SBE; 200ml com ? 800mg nitrato), 2) refresco de frutas industrializado com exerc?cio (RFE; 200ml de bebida com baixo teor de nitrato), considerado o controle com exerc?cio e 3) controle sem exerc?cio (CON; 200ml de bebida com teor insignificante de nitrato). O exerc?cio realizado foi do tipo aer?bio moderado, com intensidade de 50% da frequ?ncia card?aca de reserva, e com dura??o de 40 minutos. A concentra??o de nitritos e nitratos plasm?ticos totais (NOx) foi avaliada em quatro momentos: jejum (primeiro dia), 60 minutos (60min), 105 minutos (105min) e 165 minutos (165min) ap?s a ingest?o das bebidas (sess?o experimental). A press?o arterial (PA) ambulatorial de 24 horas (24h) foi avaliada por meio da monitoriza??o ambulatorial da press?o arterial (MAPA). Para an?lise estat?stica dos dados, foi utilizado a ANOVA de medidas repetidas e ANOVA two-way com medidas repetidas (condi??o vs. tempo) para compara??es de vari?veis entre as sess?es experimentais. Os resultados mostram que a concentra??o de NOx plasm?tico aumentou significativamente apenas na condi??o SBE em todos os momentos a partir de 60min, ap?s a ingesta do suco de beterraba, em compara??o com RFE e CON. A PA sist?lica (PAS) ambulatorial reduziu ~ 5,3 mmHg (p < 0,05) durante as primeiras seis horas p?s-exerc?cio, resultando na redu??o da PAS em ~3 mmHg (p < 0,05), e da PA diast?lica (PAD) em ~ 2 mmHg (p < 0,05) no per?odo de 24h ap?s a sess?o SBE comparado ?s sess?es RFE e CON. Em conclus?o, o suco de beterraba potencializou a resposta na PA p?s-exerc?cio ambulatorial em homens com obesidade e normotensos. / It has been shown that nitrate supplementation may reduce blood pressure in several populations. However, the effect of beetroot juice on post-exercise blood pressure response has not yet been studied. The objective of this study was to verify the effect of dietary nitrate supplementation, in the form of beetroot juice, on post-exercise blood pressure response in obese individuals. In a randomized, cross-over trial, 14 normotensive and obese men were randomly assigned to three experimental sessions: 1) beetroot juice with exercise (BJE, 200ml with ? 800mg nitrate), 2) fruit soda industrialized with exercise (FSE, 200ml of low-nitrate beverage), considered control with exercise and 3) control without exercise (CON, 200ml of drink with insignificant nitrate content). The exercise performed was of the moderate aerobic type, with intensity of 50% of the reserve heart rate and, lasting 40 minutes. The concentration of nitrites and total plasma nitrates (NOx) was evaluated at four moments: fasting (first day), 60 minutes (60min), 105 minutes (105min) and 165 minutes (165min) after drinking (experimental session). And 24-hour ambulatory blood pressure (24h) was also evaluated through ambulatory blood pressure monitoring (ABPM). For statistical analysis of the data, we used repeated measurements ANOVA and two-way ANOVA with repeated measurements (condition vs. time) for comparisons of variables between the experimental sessions. The results show that the plasma NOx concentration increased significantly only in the BJE condition at all times from 60min after the intake of beetroot juice, compared to FSE and CON. Ambulatory systolic blood pressure (SBP) decreased ~ 5.3 mmHg (p <0.05) during the first six hours post-exercise, resulting in a reduction of SBP by ~ 3 mmHg (p <0.05), and diastolic blood pressure (DBP) at ~ 2 mmHg (p <0.05) in the 24-hour period after the BJE session compared to FSE and CON sessions. In conclusion, beetroot juice potentiated ambulatory post-exercise BP responses in obese and normotensive men.
32

Implementa??o de emissores p+com diferentes dopantes para c?lulas solares n+np+ finas

Machado, Taila Cristiane Policarpi Alves 28 February 2018 (has links)
Submitted by PPG Engenharia e Tecnologia de Materiais (engenharia.pg.materiais@pucrs.br) on 2018-04-24T14:42:28Z No. of bitstreams: 1 Dissertacao Taila Final.pdf: 2384346 bytes, checksum: 8e3d52f21033cdc04d8f1c3449453ceb (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-05-08T19:50:29Z (GMT) No. of bitstreams: 1 Dissertacao Taila Final.pdf: 2384346 bytes, checksum: 8e3d52f21033cdc04d8f1c3449453ceb (MD5) / Made available in DSpace on 2018-05-08T20:07:12Z (GMT). No. of bitstreams: 1 Dissertacao Taila Final.pdf: 2384346 bytes, checksum: 8e3d52f21033cdc04d8f1c3449453ceb (MD5) Previous issue date: 2018-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The solar cells manufactured in n-type silicon, doped with phosphorus, do not present light induced degradation and they have the potential of achieving high efficiency due to the larger minority charge carrier lifetime. Besides, they are less susceptible to contamination by metal impurities. The aim of this work was to analyze different dopants to obtain the p+ region in n+np+ solar cells manufactured in Czochralski silicon wafers, solar grade, n-type, 120 ?m thick. The acceptor impurities used were B, Al, Ga, GaB and AlGa, deposited by spin-on and diffused at high temperature. The temperature, time and gases used in the process of diffusion were ranged. The sheet resistances (R?) of the diffused regions and the impurity concentration profiles were measured. We concluded that the B and GaB can be diffused at 970? C for 20 min to obtain p+ emitters with values of R? suitable to the production of solar cells with screenprinted metal grid. The Ga and AlGa require high temperatures (greater than 1100? C) and long times to produce doping profiles compatible with the production of solar cells. The Al did not produce low sheet resistance regions, even at temperatures of 1100? C. The use of argon gas instead of the nitrogen did not lead to the decreasing of the sheet resistance. The GaB is the only one doping material analyzed that can be a viable replacement for the B in the production of p+ emitter in n-type solar cells.The GaB was the only one doping material analyzed that allowed the manufacture of solar cells with the maximum efficiency of 13.5%, with the diffusion performed at 1020? C for 20 min. The FF was the main parameter that reduced the efficiency of solar cells doped with GaB when compared to the boron doped cells due to a lower shunt resistance. The n+np+ solar cell, 120 ?m thick, that achieved the highest efficiency was doped with boron and reached 14.9%, a value higher than the previously obtained in studies in the NT-Solar with thin silicon wafers. / As c?lulas solares fabricadas em l?minas de sil?cio tipo n, dopadas com f?sforo, n?o apresentam degrada??o por ilumina??o e t?m potencial de obten??o de maior efici?ncia devido ao maior valor do tempo de vida dos portadores de carga minorit?rios. Adicionalmente, s?o menos suscept?veis ? contamina??o por impurezas met?licas. O objetivo deste trabalho foi realizar uma an?lise de diferentes dopantes para obten??o da regi?o p+ em c?lulas solares n+np+fabricadas em l?minas de sil?cio Czochralski, grau solar, tipo n, com espessura de 120 ?m. Os elementos aceitadores utilizados foram o B, Al, Ga, GaB e AlGa, depositados por spin-on e difundidos em alta temperatura. Foram variadas as temperaturas, os tempos e os gases utilizados no processo de difus?o. Foi medida a resist?ncia de folha (R?) das regi?es difundidas e o perfil de concentra??o de impurezas em fun??o da profundidade. Foram desenvolvidas c?lulas solares com B, Ga, GaB e Al. Verificou-se que o B e GaB podem ser difundidos em temperatura de 970 ?C e por 20 min para obten??o de emissores com valores de R? compat?veis com a produ??o de c?lulas solares metalizadas por serigrafia. O Ga e AlGa necessitam de altas temperaturas (maiores que 1100 ?C) e tempos elevados para produzir perfis de dopantes compat?veis. O Al n?o produziu regi?es p+ de baixa R?, mesmo com a difus?o a 1100 ?C. O uso de Ar para substituir o N2 n?o acarretou em diminui??o da resist?ncia de folha. O GaB foi o ?nico dopante analisado que permitiu a fabrica??o de c?lulas solares com efici?ncia m?xima de 13,5 %, com difus?o a 1020 ?C por 20 min. O fator de forma foi o principal par?metro que reduziu a efici?ncia dos dispositivos com GaB quando comparado ao valor obtido com B devido a menor resist?ncia em paralelo. A c?lula solar n+np+ de 120 ?m de maior efici?ncia produzida neste trabalho foi dopada com boro e atingiu a efici?ncia de 14,9 %, sendo maior que as anteriormente obtidas em trabalhos realizados no NT-Solar com l?minas finas.
33

Efeito de uma sess?o de caminhada em intensidade autosselecionada ao ar livre sobre a press?o arterial ambulatorial de idosas hipertensas fisicamente inativas: um ensaio cruzado / Effect of a single session of self-paced walking outdoor on ambulatory blood pressure in inactive hypertensive older women: a crossover trial

Costa, Ingrid Bezerra Barbosa 07 August 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-03T21:24:07Z No. of bitstreams: 1 IngridBezerraBarbosaCosta_DISSERT.pdf: 991748 bytes, checksum: a15a750264875b7c40365aeca4c9afc2 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-17T23:04:53Z (GMT) No. of bitstreams: 1 IngridBezerraBarbosaCosta_DISSERT.pdf: 991748 bytes, checksum: a15a750264875b7c40365aeca4c9afc2 (MD5) / Made available in DSpace on 2017-11-17T23:04:53Z (GMT). No. of bitstreams: 1 IngridBezerraBarbosaCosta_DISSERT.pdf: 991748 bytes, checksum: a15a750264875b7c40365aeca4c9afc2 (MD5) Previous issue date: 2017-08-07 / OBJETIVO: analisar o efeito de uma sess?o de caminhada em intensidade autosselecionada ao ar livre sobre a press?o arterial (PA) ambulatorial de idosas hipertensas fisicamente inativas. METODOLOGIA: vinte idosas hipertensas medicadas (64,9 ? 4,5 anos; 29,0 ? 4,3 kg/m?; PA de repouso 121,5 ? 11,2 / 59,5 ? 7,9 mmHg) e fisicamente inativas (< 8.000 passos/dia) completaram esse ensaio cl?nico controlado e randomizado, com delineamento cruzado. Ap?s avalia??o inicial, as idosas participaram de duas sess?es em ordem randomizada, com uma semana de intervalo entre elas: i) sess?o de caminhada em intensidade autosselecionada ao ar livre (pista de 400 m) e ii) sess?o controle (sem exerc?cio). Ambas as sess?es foram realizadas pela manh? entre 7:00-8:00 h. Durante a caminhada a frequ?ncia card?aca (FC), percep??o subjetiva do esfor?o (PSE, 6-20) e resposta afetiva (RA, -5/+5) foram monitoradas. A PA ambulatorial foi avaliada durante 20 h (vig?lia: 13 h; sono: 7 h) ap?s as sess?es de caminhada e controle atrav?s da monitoriza??o ambulatorial da press?o arterial (MAPA). Os resultados est?o descritos em m?dia e intervalo de confian?a de 95%. A PA sist?lica e diast?lica no per?odo de 20 h, vig?lia e sono foram comparadas entre as sess?es caminhada e controle usando o teste de t de Student pareado. A ANOVA two-way (condi??o vs. tempo) com medidas repetidas no segundo fator foi utilizada para comparar os valores m?dios de PA ambulatorial nos per?odos 1-6 h e 7-13 h (vig?lia) e 14-20 h (sono) ap?s as sess?es caminhada e controle. O p?s-teste de Bonferroni foi utilizado para verificar as diferen?as pontuais. Um p-valor < 0,05 foi considerado estatisticamente significativo. RESULTADOS: a intensidade de caminhada autosselecionada foi 58,6% (54,1-63,5) da FC de reserva, a PSE foi 11 (10-12) e a RA foi +3 (3-4). A PA sist?lica foi 3,4 mmHg (0,9-5,9) e 4,0 mmHg (1,6-6,4) menor nas m?dias dos per?odos de 20 h e vig?lia, respectivamente, ap?s a sess?o de caminhada quando comparada a sess?o controle (p < 0,05). A redu??o da PA sist?lica p?s-caminhada apresentou maior magnitude nas seis primeiras horas (6 mmHg; p < 0,05). N?o houve redu??o da PA sist?lica p?s-caminhada no per?odo do sono (p > 0.05). Nenhuma altera??o da PA diast?lica p?s-caminhada foi observada no per?odo de 20 h, vig?lia e sono em rela??o ? sess?o controle (p > 0,05). Foi observada redu??o da carga press?rica sist?lica (6,3%) e variabilidade da PA sist?lica (6,2 unidades arbitr?rias) p?s-caminhada no per?odo de 20 h (p < 0,05). Houve correla??o forte e positiva entre a redu??o da PA sist?lica nas seis primeiras hora p?s-caminhada com a redu??o no per?odo de 20 h (r = 0,68; p <0,001). CONCLUS?O: uma sess?o de caminhada em intensidade autosselecionada ao ar livre reduz a PA sist?lica m?dia no per?odo de 20 h e vig?lia em idosas hipertensas, essencialmente pela HPE nas primeiras seis horas p?s-exerc?cio. Al?m disso, reduz a carga press?rica sist?lica e variabilidade da PA sist?lica no per?odo de 20 h. Considerando que as idosas percebem a sess?o como leve-moderada e prazerosa, a caminhada em intensidade autosselecionada parece ser uma alternativa interessante para recomenda??o inicial de exerc?cio para idosas hipertensas fisicamente inativas. / OBJETIVO: analisar o efeito de uma sess?o de caminhada em intensidade autosselecionada ao ar livre sobre a press?o arterial (PA) ambulatorial de idosas hipertensas fisicamente inativas. METODOLOGIA: vinte idosas hipertensas medicadas (64,9 ? 4,5 anos; 29,0 ? 4,3 kg/m?; PA de repouso 121,5 ? 11,2 / 59,5 ? 7,9 mmHg) e fisicamente inativas (< 8.000 passos/dia) completaram esse ensaio cl?nico controlado e randomizado, com delineamento cruzado. Ap?s avalia??o inicial, as idosas participaram de duas sess?es em ordem randomizada, com uma semana de intervalo entre elas: i) sess?o de caminhada em intensidade autosselecionada ao ar livre (pista de 400 m) e ii) sess?o controle (sem exerc?cio). Ambas as sess?es foram realizadas pela manh? entre 7:00-8:00 h. Durante a caminhada a frequ?ncia card?aca (FC), percep??o subjetiva do esfor?o (PSE, 6-20) e resposta afetiva (RA, -5/+5) foram monitoradas. A PA ambulatorial foi avaliada durante 20 h (vig?lia: 13 h; sono: 7 h) ap?s as sess?es de caminhada e controle atrav?s da monitoriza??o ambulatorial da press?o arterial (MAPA). Os resultados est?o descritos em m?dia e intervalo de confian?a de 95%. A PA sist?lica e diast?lica no per?odo de 20 h, vig?lia e sono foram comparadas entre as sess?es caminhada e controle usando o teste de t de Student pareado. A ANOVA two-way (condi??o vs. tempo) com medidas repetidas no segundo fator foi utilizada para comparar os valores m?dios de PA ambulatorial nos per?odos 1-6 h e 7-13 h (vig?lia) e 14-20 h (sono) ap?s as sess?es caminhada e controle. O p?s-teste de Bonferroni foi utilizado para verificar as diferen?as pontuais. Um p-valor < 0,05 foi considerado estatisticamente significativo. RESULTADOS: a intensidade de caminhada autosselecionada foi 58,6% (54,1-63,5) da FC de reserva, a PSE foi 11 (10-12) e a RA foi +3 (3-4). A PA sist?lica foi 3,4 mmHg (0,9-5,9) e 4,0 mmHg (1,6-6,4) menor nas m?dias dos per?odos de 20 h e vig?lia, respectivamente, ap?s a sess?o de caminhada quando comparada a sess?o controle (p < 0,05). A redu??o da PA sist?lica p?s-caminhada apresentou maior magnitude nas seis primeiras horas (6 mmHg; p < 0,05). N?o houve redu??o da PA sist?lica p?s-caminhada no per?odo do sono (p > 0.05). Nenhuma altera??o da PA diast?lica p?s-caminhada foi observada no per?odo de 20 h, vig?lia e sono em rela??o ? sess?o controle (p > 0,05). Foi observada redu??o da carga press?rica sist?lica (6,3%) e variabilidade da PA sist?lica (6,2 unidades arbitr?rias) p?s-caminhada no per?odo de 20 h (p < 0,05). Houve correla??o forte e positiva entre a redu??o da PA sist?lica nas seis primeiras hora p?s-caminhada com a redu??o no per?odo de 20 h (r = 0,68; p <0,001). CONCLUS?O: uma sess?o de caminhada em intensidade autosselecionada ao ar livre reduz a PA sist?lica m?dia no per?odo de 20 h e vig?lia em idosas hipertensas, essencialmente pela HPE nas primeiras seis horas p?s-exerc?cio. Al?m disso, reduz a carga press?rica sist?lica e variabilidade da PA sist?lica no per?odo de 20 h. Considerando que as idosas percebem a sess?o como leve-moderada e prazerosa, a caminhada em intensidade autosselecionada parece ser uma alternativa interessante para recomenda??o inicial de exerc?cio para idosas hipertensas fisicamente inativas.
34

Estudo da sinterabilidade de ligas de n?quel obtidas por meio dos portadores de liga sic, si3n4 ou si met?lico com grafita

Nicodemo, Juliana Pivotto 06 June 2012 (has links)
Made available in DSpace on 2014-12-17T14:07:04Z (GMT). No. of bitstreams: 1 JulianaPN_DISSERT.pdf: 2953662 bytes, checksum: 47355bc7fed206f60c6c6b5d8565099b (MD5) Previous issue date: 2012-06-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Nickel alloys are frequently used in applications that require resistance at high temperatures associated with resistance to corrosion. Alloys of Ni-Si-C can be obtained by means of powder metallurgy in which powder mixtures are made of metallic nickel powders with additions of various alloying carriers for such were used in this study SiC, Si3N4 or Si metal with graphite. Carbonyl Ni powder with mean particle size of 11 mM were mixed with 3 wt% of SiC powders with an average particle size of 15, 30 and 50 &#956;m and further samples were obtained containing 4 to 5% by mass of SiC with average particle size of 15 &#956;m. Samples were also obtained by varying the carrier alloy, these being Si3N4 powder with graphite, with average particle size of 1.5 and 5 &#956;m, respectively. As a metallic Si graphite with average particle size of 12.5 and 5 &#956;m, respectively. The reference material used was nickel carbonyl sintered without adding carriers. Microstructural characterization of the alloys was made by optical microscopy and scanning electron microscopy with semi-quantitative chemical analysis. We determined the densities of the samples and measurement of microhardness. We studied the dissociation of carriers alloy after sintering at 1200 ? C for 60 minutes. Was evaluated also in the same sintering conditions, the influence of the variation of average particle size of the SiC carrier to the proportion of 3% by mass. Finally, we studied the influence of variation of the temperatures of sintering at 950, 1080 and 1200 ? C without landing and also with heights of 30, 60, 120 and 240 minutes for sintering where the temperature was 950 ?C. Dilatometry curves showed that the SiC sintered Ni favors more effectively than other carriers alloy analyzed. SiC with average particle size of 15 &#956;m active sintering the alloy more effectively than other SiC used. However, with the chemical and morphological analyzes for all leagues, it was observed that there was dissociation of SiC and Si3N4, as well as diffusion of Si in Ni matrix and carbon cluster and dispersed in the matrix, which also occurred for the alloys with Si carriers and metallic graphite. So the league that was presented better results containing Si Ni with graphite metallic alloy as carriers, since this had dispersed graphite best in the league, reaching the microstructural model proposed, which is necessary for material characteristic of solid lubricant, so how we got the best results when the density and hardness of the alloy / Ligas de N?quel s?o freq?entemente utilizadas em aplica??es que requerem resist?ncia mec?nica a elevadas temperaturas associada ? resist?ncia ? corros?o. Ligas de Ni-Si-C podem ser obtidas por meio de metalurgia do p? em que s?o realizadas misturas de p?s de n?quel met?lico com adi??es de p?s de diferentes portadores de liga, para tal foram utilizados neste trabalho SiC, Si3N4 ou Si met?lico com grafita. P?s de Ni carbonila com tamanho m?dio de part?culas de 11 &#956;m foram misturados a 3% em massa de p?s de SiC com tamanho m?dio de part?culas de 15, 30 e 50 &#956;m e foram obtidas ainda amostras contendo 4 e 5% em massa de SiC com tamanho m?dio de part?culas de 15 &#956;m. Tamb?m foram obtidas amostras variando-se o portador de liga, sendo estes p?s de Si3N4 com grafita, com tamanho m?dio de part?culas de 1,5 e 5 &#956;m, respectivamente. Assim como Si met?lico com grafita, com tamanho m?dio de part?culas de 12,5 e 5 &#956;m, respectivamente. O material de refer?ncia adotado foi n?quel carbonila sinterizado sem adi??o de portadores. A caracteriza??o microestrutural das ligas foi feita por microscopia ?ptica e eletr?nica de varredura com an?lise qu?mica semi-quantitativa. Foram determinadas as densidades das amostras e obtidas medidas de microdureza Vickers. Foi estudada a dissocia??o dos portadores de liga ap?s sinteriza??o em 1200 ?C durante 60 minutos. Foi avaliada, ainda, para as mesmas condi??es de sinteriza??o, a influencia da varia??o do tamanho m?dio de part?culas do portador SiC, para a propor??o de 3% em massa. Por fim, foi estudo a influencia da varia??o das temperaturas de sinteriza??o em 950, 1080 e 1200 ?C sem patamar e, ainda, com patamares de 30, 60, 120 e 240 minutos para sinteriza??o cuja temperatura foi de 950 ?C. As curvas de dilatometria mostraram que o SiC favorece a sinteriza??o do Ni de forma mais eficaz que os demais portadores de liga analisados. O SiC com tamanho m?dio de part?culas de 15 &#956;m ativa a sinteriza??o da liga de forma mais eficaz que os demais SiC utilizados. Por?m, com as an?lises qu?mica e morfol?gica para todas as ligas, foi poss?vel observar que houve dissocia??o do SiC e do Si3N4, assim como difus?o do Si na matriz de Ni e carbono aglomerado e disperso na matriz, o que tamb?m ocorreu para as ligas com portadores Si met?lico e grafita. Portanto, a liga que apresentou melhores resultados foi de Ni contendo Si met?lico com grafita como portadores de liga, j? que esta apresentou grafita melhor dispersa na liga, atingindo o modelo microestrutural proposto, do qual ? necess?rio para material com caracter?stica de lubrificante s?lido, assim como obteve os melhores resultados quando a densidade e dureza da liga
35

An?lise da concep??o arquitetural ? luz da arquiteturologia: um estudo da produ??o de edif?cios de uso n?o-residencial do arquiteto Jo?o Maur?cio Fernandes de Miranda, entre 1961 e 1981

Pereira, Marizo Vitor 19 March 2008 (has links)
Made available in DSpace on 2014-12-17T13:56:55Z (GMT). No. of bitstreams: 1 MarizoVP.pdf: 4894684 bytes, checksum: 6f0e9e9cb330df448c32101a1015a14b (MD5) Previous issue date: 2008-03-19 / This study explores the architectural conception process using the Architecturologie as an instrument of analysis, based on Enseigner la Conception Architecturale (2000), developed by Boudon - architect, lecturer and French researcher. It begins with the selection of local architect?s works, Jo?o Maur?cio Fernandes de Miranda, which resulted in six non residential projects developed between 1961 and 1981. Architectural readings were developed, with emphasis in the identification of architecturological scales, their functions, relationship and modality of occurrence / Este trabalho apresenta um estudo sobre a concep??o arquitetural, tendo como refer?ncia a Arquiteturologia, abordagem desenvolvida por Philippe Boudon, arquiteto, professor e pesquisador franc?s. A partir de um recorte temporal (anos 1961/1981) foi feita uma sele??o na produ??o do arquiteto potiguar Jo?o Maur?cio Fernandes de Miranda, reunindo seis exemplares - projetos de uso n?o-residencial, sobre os quais foram realizadas leituras arquiteturol?gicas. O objetivo Geral da pesquisa ? exercitar o uso da metodologia de trabalho desenvolvida por Philippe Boudon e equipe em sua obra Enseigner la Conception Architecturale (2000), com ?nfase especial na identifica??o das escalas arquiteturol?gicas, suas fun??es, rela??es e modalidades de ocorr?ncia. A Arquiteturologia, portanto, sendo utilizada como instrumento de estudo da concep??o arquitetural
36

Um olhar sobre a obra de Ac?cio Gil Borsoi obras e projetos residenciais 1953-1970

Silva, Izabel Fraga do Amaral e 12 August 2004 (has links)
Made available in DSpace on 2014-12-17T13:57:11Z (GMT). No. of bitstreams: 1 IzabelFAS_ate_apendiceA.pdf: 3897141 bytes, checksum: ee3b61a8271b982a3e8108a50eb792b0 (MD5) Previous issue date: 2004-08-12 / This essay studies the contribution of architect Ac?cio Gil Borsoi (1924-), who played an important role in the consolidation of Modern Architecture in the Northeast of Brazil. The universe analyzed is constituted of 48 residential projects, houses and apartment buildings, both built and unbuilt, dating from 1953 to 1970. Considering an analogy between architecture and language, the selected projects were analyzed focusing in the process of creation / Este trabalho estuda a contribui??o do arquiteto Ac?cio Gil Borsoi (1924-), importante figura da consolida??o da Arquitetura Moderna no Nordeste brasileiro. O universo analisado ? constitu?do de 48 projetos residenciais, casas e edif?cios de apartamentos, constru?dos ou n?o, abrangendo o per?odo de 1953-1970. Levando em considera??o a analogia entre arquitetura e linguagem buscou-se analisar os projetos selecionados com objetivo de estudar o processo de cria??o
37

Efeito agudo do exerc?cio intervalado de alta intensidade de baixo volume sobre a press?o arterial ambulatorial de normotensos / Acute effect of low-volume high-intensity interval exercise on ambulatorial blood pressure in normotensive

Dantas, Teresa Cristina Batista 31 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-04T14:08:48Z No. of bitstreams: 1 TeresaCristinaBatistaDantas_DISSERT.pdf: 2035837 bytes, checksum: 9e4bbb8e58581fb11c89382b14e4a5b1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-13T14:55:41Z (GMT) No. of bitstreams: 1 TeresaCristinaBatistaDantas_DISSERT.pdf: 2035837 bytes, checksum: 9e4bbb8e58581fb11c89382b14e4a5b1 (MD5) / Made available in DSpace on 2017-07-13T14:55:41Z (GMT). No. of bitstreams: 1 TeresaCristinaBatistaDantas_DISSERT.pdf: 2035837 bytes, checksum: 9e4bbb8e58581fb11c89382b14e4a5b1 (MD5) Previous issue date: 2016-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Introdu??o: estudos demonstram a ocorr?ncia de hipotens?o p?s-exerc?cio (HPE) ap?s ~60 minutos de exerc?cio intervalado de alta intensidade (EIAI) em normotensos. Entretanto, existe uma lacuna no que se refere a HPE ambulatorial e ainda n?o ? conhecido se os modelos de EIAI de baixo volume s?o capazes de reduzir a press?o arterial (PA) ambulatorial em normotensos. Objetivo: investigar o efeito de uma sess?o de EIAI de baixo volume sobre a PA ambulatorial de normotensos. M?todos: vinte e um homens normotensos (23,6 ? 3,6 anos; 23,5 ? 2,3 kg/m2; PA de repouso 111,1 ? 6,4 / 62,4 ? 6,1 mmHg) realizaram: (i) teste incremental m?ximo; (ii) sess?o EIAI e controle (sem exerc?cio) em ordem randomizada. O EIAI consistiu de 10x60s a 100% da velocidade m?xima atingida no teste de esfor?o intercalado com 60s de recupera??o passiva. Os sujeitos permaneceram 20h com o aparelho de Monitoriza??o Ambulatorial da Press?o Arterial (MAPA). Foram avaliadas 13h de vig?lia e 7h de sono. O teste t de Student pareado foi utilizado para comparar a PA sist?lica e diast?lica entre as sess?es controle e EIAI. A ANOVA two-way (condi??o vs. tempo) foi usada para comparar a PA ambulatorial hora a hora ap?s as sess?es controle e EIAI. Resultados: a PA sist?lica no per?odo de 20h de an?lise reduziu 2,8 ? 3,7 mmHg e a PA diast?lica reduziu 1,7 ? 3,5 mmHg ap?s a sess?o de EIAI em rela??o ? sess?o controle (p<0,05). No per?odo da vig?lia, a PA sist?lica reduziu 3,2 ? 3,7 mmHg e a PA diast?lica 1,8 ? 3,9 mmHg ap?s a sess?o de EIAI em rela??o ? sess?o controle (p<0,05). N?o houve diferen?a na PA sist?lica e diast?lica durante o per?odo do sono (p>0,05). A ANOVA two-way demostrou que a PA sist?lica foi menor nas primeiras cinco horas ap?s a sess?o EIAI comparada a sess?o controle [delta m?nimo: -3,2 mmHg; delta m?ximo: -4,8 mmHg (p<0,05)]. Conclus?es: uma sess?o de EIAI de baixo volume reduziu a PA na vig?lia e no per?odo de 20h em normotensos. A hipotens?o em maior magnitude ocorrida nas primeiras cinco horas p?s-exerc?cio parecer explicar a redu??o da PA na vig?lia e no per?odo de 20h. / Introduction: Previous research have already shown the occurrence of post-exercise hypotension (PEH) after ~60 minutes of high-intensity interval exercise (HIIE) in normotensive subjects. However, there is a gap with regard to ambulatory PEH and it is not yet knowns if the low-volume HIIE reduces ambulatory blood pressure (BP) in normotensive subjects. Objective: To investigate the effect of a single session of low-volume HIIE on ambulatory BP in normotensive subjects. Methods: Twenty-one normotensive males (23.6 ? 3.6 years, 23.5 ? 2.3 kg/m2, resting PA 111.1 ? 6.4 / 62.4 ? 6.1 mmHg) performed: (i) maximum incremental test; (ii) HIIE and control sessions in a randomized order. The HIIE consisted of 10x60s at 100% of maximal velocity interspersed by 60s of passive recovery. The paired sample t-test was used to compare systolic and diastolic BP between control and HIIE sessions. A two-way ANOVA (condition vs. time) was used to compare the ambulatory BP response hour to hour following the control and HIIE sessions. Results: Systolic BP in the 20-hour analysis reduced 2.8 ? 3.7 mmHg and diastolic BP reduced 1.7 ? 3.5 mmHg after the HIIE session compared to the control session (p<0.05). In the awake period, systolic BP decreased 3.2 ? 3.7 mmHg and diastolic BP 1.8 ? 3.9 mmHg after the HIIE session compared to the control session (p<0.05). There was no difference in the systolic and diastolic BP during the asleep period (p> 0.05). The two-way ANOVA demonstrated that systolic BP was lower in the first five hours after the HIIE session compared to the control session [minimum delta: -3.2 mmHg; maximum delta: -4.8 mmHg (p <0.05)]. Conclusion: A single session of low-volume HIIE reduces ambulatory BP in normotensive. The greater magnitude of hypotension during the first five hours post-exercise seems to explain the BP reduction in 20h and awake periods.
38

How newly appointed chief information officers take charge : exploring the dynamics of leader socialization

Gerth, Anthony B. January 2013 (has links)
The transition for any executive into a new appointment is a challenge. This transition for the newly appointed Chief Information Officer (CIO) is especially challenging given the complexity and ambiguous nature of their role. Investment in information technology (IT) has steadily increased over the past twenty years and contributes to enabling business changes that drive organizational performance improvements. The role of the Chief Information Officer (CIO) has evolved into an executive who holds significant responsibility for leading the organization in realizing these investment benefits. Therefore unsuccessful CIO transitions can negatively impact the extent to which the organization’s IT benefits are fully realized. This research has one objective: to increase our understanding of the process of taking charge for the newly appointed Chief Information Officer (CIO). This increased understanding contributes to academic research as well as provides insights to practicing CIOs that will increase their probability of successfully taking charge of a new appointment. The project explores this phenomenon in depth from both the CIO’s and non-IT executive’s (CxO) perspective through semi-structured interviews with 43 executives. Participants included twenty-one Chief Information Officers and twenty-two C-suite, non-IT executives. The study integrates concepts from role theory and leader socialization with CIO leadership challenges. Findings indicate that the newly appointed CIO experiences a mutual adjustment process when they take charge. This adjustment occurs within their role set; the IT leadership team, the Chief Executive Officer (CEO) and the other top management team members (CxOs). The data suggests that CIOs experience three overlapping phases of taking charge; Entry, Stabilization and Renewal. These phases result in confidence, credibility and legitimacy as a new leader in the organization. The data further reveals that the type of transition (Start-up, Turnaround, Realignment or Success-sustaining) encountered by the CIO is a significant influence on the taking charge process. CIO socialization is influenced heavily by their role set and the expectations within it. CIOs will encounter CxO peers with varying preferences on interaction style and focus. In addition the CxOs in the study identified three different views of CIOs that reinforce the role ambiguity for the newly appointed CIO. The study reveals that CIOs experience organizational socialization in two domains of leadership. These domains are supply-side and demand-side leadership. The data suggests that supply-side socialization occurs prior to demand-side socialization. These socialization outcomes are dependent on transition type. This research extends previous work done on CIO transitions by identifying phases, activities and outcomes. An additional contribution is the first empirical model of new CIO socialization. Leader socialization research is enhanced with the study of a non-CEO executive. This model contributes a deeper understanding of the mutual adjustment process experienced by a newly appointed CIO. Practicing CIOs can apply these findings in developing transition plans and actions for taking a new appointment. The CxO types and attitudes can inform the newly appointed CIO on customizing their relationship building approaches. Understanding that taking charge requires 2-3 years can lead to more realistic expectations of the executive. The findings of this study can lead CIOs to a higher probability of success in taking charge of a new appointment.
39

Investigating the Relationship between Governance Mechanisms and the Disclosure of IT Control Weaknesses

Hamdan, Basil 01 January 2011 (has links)
The current research is concerned with exploring the quality of information technology (IT) control over financial reporting systems as reported under Section 404 of the Sarbanes-Oxley Act of 2002. More specifically, this dissertation examines the association between organizational governance mechanisms and the occurrence and subsequent disclosure of IT control weaknesses. Despite the adverse impact of IT control weaknesses on internal control quality and financial reporting reliability, research on IT controls in general and IT control weaknesses in particular remains largely anecdotal with limited reliance on theory. The current work proposes and tests an integrated theoretical model of the antecedents of IT control weaknesses. The proposed model draws upon agency theory to provide a theoretical perspective of the occurrence of IT control weaknesses and upon corporate governance literature to solicit potential factors that influence the achievement of effective IT control over financial reporting. Drawing upon agency theory, this research views the existence of IT control weaknesses as a manifestation of an agency problem caused by information asymmetry and lack of alignment between the overall organization represented by its board of directors as a principal and its information systems (IS) organization represented by the top IS team as an agent. Drawing on corporate governance literature, this dissertation proposes two categories of governance and contracting mechanisms that the board of directors can employ to reduce information asymmetry and align the interests of the top IS team with those of the firm thereby reducing the agency problem. These categories are: IT governance mechanisms and IT executive incentive alignment mechanisms. The IT governance mechanisms involve two elements: first, the IT background element which includes (a) the IT background of the board of directors as reflected by two of its main committees, namely the corporate governance committee and the audit committee and (b) the IT background of the top management team; second, the IT executive element as reflected in terms of the structural and the expert power of the Chief Information Officer (CIO). The IT executive incentive alignment mechanisms include two elements: (a) the CIO’s absolute compensation level and (b) the pay disparity between the CIO and other members of the top management team. A research model integrating these elements is developed and tested with empirical data. For testing the proposed model, this dissertation uses a sample of firms with IT control weaknesses and a control group of similar firms with no IT control weaknesses for the years 2005-2009. Empirical results provide support for five of the seven hypotheses put forth in this research. Regarding the IT governance mechanisms, study findings indicate that a lower likelihood of disclosing IT-related control weaknesses is associated with having audit committee and corporate governance committee members with IT expertise. Furthermore, the study findings provide support for the contention that the goal congruence is contingent on the CIO’s power. To this end, the study finds that a lower likelihood of disclosing IT-related control weaknesses is associated with having CIOs with higher levels of structural and expert power. As for the incentive alignment mechanisms, empirical results provide support for the assertion that goal congruence is contingent on perceived pay equality between the CIO and other members of the top management team. The results indicate that the lower the pay disparity between IT executives and business executives in the top management team, the lower the likelihood of disclosing IT control weaknesses. The present study contributes to the current body of knowledge of literature in several ways. It is the first study to propose and test an integrated model of the antecedents of IT control weaknesses. The proposed model adds to the current literature by introducing agency theory as a theoretical basis of the antecedents of IT control weaknesses. Furthermore, this study adds to the current literature by introducing and providing empirical evidence linking the IT background of the corporate governance committee, the structural power and expert power of the CIO, and the CIO relative pay to the disclosure of IT control weaknesses over financial reporting. Lastly, this research contributes to practice by offering a much needed understanding for managers, directors, auditors, and regulators in their effort to improve the quality of IT control and the reliability of financial reporting.
40

Reproductive outcomes in progesterone-based fixed-time AI protocols in Bos indicus / Parâmetros reprodutivos em protocolos de IA em tempo fixo à base de progesterona em Bos indicus

Madureira, Guilherme 26 April 2019 (has links)
To improve the knowledge on progesterone (P4)-based hormonal protocols for synchronization of ovulation in Bos indicus, three studies were performed. The first study, consisting of three experiments (two in non-lactating cows, and one in Nelore heifers), were based on daily ultrasound evaluation and blood sampling for circulating P4 at specific times [onset of the protocol (D0) and first prostaglandin F2&#945; (PGF) administration] of P4-based protocols differing in: inducer of the follicle wave emergence; protocol lengths; and ovulation inducer at the end of the protocol. Administration of 16.8 &#181;g of buserelin acetate (GnRH) at the beginning of the protocol was associated with better ovulation rate after D0 (~55%), and higher number of corpus luteum (CL) at PGF. In addition, sometimes GnRH-based protocols were associated to early emergence of the follicle wave (~1.9 d after D0) and/or bigger ovulatory follicle, as well as greater circulating P4 at the time of PGF, especially in females that ovulated after GnRH administration. Nevertheless, protocols based on estradiol benzoate (EB) promoted delayed follicular wave emergence (~2.4 d after D0), but both (GnRH and EB) were associated to satisfactory synchronization rate of follicular wave emergence between D0 and D5 (~92%). In contrast, short protocols (5 d of P4 implant) only with insertion of a P4 implant on D0 were associated to low follicle wave emergence between D0 and D5 (~30%). However, the three strategies mentioned above promoted high ovulation rate at the end of the protocol (~85%), and did not differ in relation to the time of ovulation. The second study, consisting of two experiments (one in Nelore heifers, and the second in Nelore cows), evaluated fertility and some physiological variables of P4-based 7 d protocols beginning with EB (conventional protocol) or GnRH (16.8 &#181;g of buserelin acetate) with adaptations (eCG and PGF on D6, and an additional PGF on D7), and with or without GnRH (8.4 &#181;g) administration at the time of AI. As expected, higher ovulation rate after D0 (~67%) and more CL at PGF were observed in protocols starting with GnRH. Administration of EB at the beginning of the protocol was associated to greater luteolysis rate between D0 and PGF (~33%). At the time of implant withdrawal (D7), GnRH-based protocols induced bigger dominant follicles, and more estrus expression by the time of AI. However, only in heifers it was observed a bigger dominant follicle at the time of AI for GnRH group. Both (GnRH and EB) obtained satisfactory ovulation rate after AI (~92%). In heifers, no treatment effect was observed (EB vs. GnRH on D0, with vs. without GnRH at the time of AI) or interactions on pregnancy/AI (P/AI). However, in cows EB-based protocols obtained great P/AI when GnRH was administered at the time of AI (60.2% vs. 69.5%). In addition, this administration also increased P/AI of cows that did not express estrus during the protocol (no estrus: no GnRH = 48.2% vs. GnRH = 59.1%), although this effect was not observed in heifers. The third study evaluated ovarian dynamics and fertility of Nelore cows submitted to a P4-based 7 d FTAI protocol using 0.5 or 1.0 mg of estradiol cypionate (EC) at the time of implant removal (D7). Although 1.0 mg EC induced a smaller preovulatory follicle and lower ovulation rate after AI in multiparous, the P/AI was similar for both doses in this parity (multiparous: 0.5 mg = 58.4% vs. 1.0 mg = 59.0%). However, primiparous had lower P/AI when receiving 0.5 mg EC (primiparous: 0.5 mg = 30.2% vs. 1.0 mg = 53.6%). Therefore, both studies allowed a more refined knowledge regarding P4-based protocols in Bos indicus, especially on the efficiency of 7 d protocols and the inclusion of GnRH at the start or in the end of this type of synchronization protocol. / Com o intuito de aprofundar o conhecimento sobre protocolos hormonais de sincronização da ovulação à base de progesterona (P4) em Bos indicus, três estudos foram realizados. O primeiro estudo, composto por três experimentos (dois em vacas Nelore não-lactantes, e um em novilhas Nelore), baseou-se em avaliações ultrassonográficas diárias e colheitas de sangue para P4 circulante em momentos pontuais [início do protocolo (D0) e administração da primeira prostaglandina F2&#945; (PGF)] de protocolos à base de P4 diferindo em: indutor de emergência de onda folicular; duração do protocolo; e indutor da ovulação ao final do protocolo. A administração de 16,8 &#181;g de acetato de buserelina (GnRH) ao início do protocolo promoveu maiores taxas de ovulação após o D0 (~55%) e também maior número de corpos lúteos (CL) no momento da PGF. Em alguns momentos, protocolos à base de GnRH estiveram associados a antecipação da emergência de onda folicular (~1,9 d após D0) e/ou maior folículo ovulatório, bem como maior P4 circulante no momento da PGF, e pontualmente em fêmeas que ovularam após a administração deste fármaco. Não obstante, protocolos à base de benzoato de estradiol (BE) promoveram atraso na emergência da onda folicular (~2,4 d após D0), porém ambos (GnRH e BE) estiveram associados a alta taxa de sincronização da emergência de onda folicular entre D0 e D5 do protocolo (~92%). Em contrapartida, protocolos curtos (5 d de implante de P4), apenas com a inserção de implante de P4 no D0, estiveram associados à baixa taxa de emergência de onda folicular (~30%). Entretanto, as três estratégias citadas acima promoveram alta taxa de ovulação ao final do protocolo (~85%), e não diferiram em relação ao horário da ovulação. O segundo estudo, composto por dois experimentos (um em novilhas Nelore e o segundo em vacas Nelore), testou a fertilidade e variáveis fisiológicas de protocolos à base de P4 com duração de 7 d iniciando com BE (convencional) ou com GnRH (16,8 &#181;g de acetato de buserelina) com adaptações (eCG e PGF no D6, e uma PGF adicional no D7), e com ou sem a administração de GnRH (8,4 &#181;g) no momento da IATF. Ambos também receberam cipionato de estradiol (CE) no D7. Como esperado, observou-se maior taxa de ovulação (~67%) após o D0 e maior número de CL na PGF em protocolos iniciando com GnRH. A administração de BE ao início do protocolo esteve associada a maior luteólise entre D0 e PGF (~33%). No momento da retirada do implante (D7), protocolos à base de GnRH promoveram maior folículo dominante, e além disso, mais expressão de estro até a IATF. Contudo, apenas em novilhas observou-se maior folículo dominante no momento da IATF para o grupo GnRH. Ambos protocolos (iniciados com GnRH ou BE) obtiveram altas taxas de ovulação após a IATF (~92%). Em novilhas, não se observou efeito de tratamento (BE vs. GnRH no D0, com vs. sem GnRH na IATF) ou interações sobre a prenhez/IA (P/IA). Entretanto, em vacas, protocolos à base de BE obtiveram maior P/IA quando houve a administração de GnRH no momento da IATF (60,2% vs. 69,5%). Além disso, GnRH na IATF também favoreceu a P/IA de vacas que não expressaram estro durante o protocolo (Sem cio: sem GnRH 48,2% vs. com GnRH 59,1%), apesar de não ter sido observado este efeito em novilhas. O terceiro estudo avaliou a fertilidade e dinâmica ovariana de vacas Nelore submetidas a protocolo à base de P4 com duração de 7 d utilizando 0,5 ou 1,0 mg de CE no momento da retirada do implante (D7). Apesar de 1,0 mg CE produzir menor folículo preovulatório e menor taxa de ovulação após a IA em multíparas, a P/IA foi semelhante para ambas as doses nesta categoria (multíparas: 0,5 mg = 58,4% vs. 1,0 mg = 59,0%). Contudo, primíparas tiveram menor P/IA ao receber 0,5 mg CE (primíparas: 0,5 mg = 30,2% vs. 1,0 mg = 53,6%). Portanto, os estudos permitiram um conhecimento mais refinado em relação a protocolos à base de P4 em Bos indicus, especialmente quanto à eficiência de protocolos de 7 d e inclusão de GnRH tanto ao início quanto ao final.

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