Análisis de salto vertical repetido en jugadores de baloncesto

Con el propósito de analizar los cambios de la fuerza máxima explosiva en relación a la ejecución de series de salto vertical repetido (SVR) con periodos cortos de recuperación pasiva en jugadores de baloncesto, se evaluaron 12 deportistas en un protocolo de cuatro series (S) de 15-s de saltos verticales con 10-s de recuperación entre S. Se midieron la altura de salto inicial (ASI) y final (ASF) de cada S; se utilizó ANOVA de una vía con post hoc de Bonferroni para el análisis de las diferencias ASF-ASI por S y una prueba t de Student para analizar el índice de fatiga (IF) por serie. Se encontró que la diferencia ASF-ASI fue progresivamente incremental desde la S1 hasta la S4 (-2,8 6,2 cm, -6,8 4,9 cm, -8,4 5,6 cm y -9,3 5,9 cm, respectivamente), aunque la diferencia fue mayor solo en S4 con respecto a S1 (p=0,014). Es posible que los períodos de recuperación entre cada S influyeron en el mantenimiento de la fuerza muscular explosiva (FME) durante los primeros 45-s de saltos, sin embargo, la suma de estas ejecuciones generó un aumento de la fatiga al final de la prueba. La FME puede ser afectada por la suma de ejecuciones de SVR aun con la inclusión de períodos cortos de recuperación entre series. La relación trabajo-recuperación en baloncesto es un factor que debe considerarse para planificar el entrenamiento en jugadores de baloncesto.

Análisis de salto vertical repetido en jugadores de baloncesto

Con el propósito de analizar los cambios de la fuerza máxima explosiva en relación a la ejecución de series de salto vertical repetido (SVR) con periodos cortos de recuperación pasiva en jugadores de baloncesto, se evaluaron 12 deportistas en un protocolo de cuatro series (S) de 15-s de saltos verticales con 10-s de recuperación entre S. Se midieron la altura de salto inicial (ASI) y final (ASF) de cada S; se utilizó ANOVA de una vía con post hoc de Bonferroni para el análisis de las diferencias ASF-ASI por S y una prueba t de Student para analizar el índice de fatiga (IF) por serie. Se encontró que la diferencia ASF-ASI fue progresivamente incremental desde la S1 hasta la S4 (-2,8 6,2 cm, -6,8 4,9 cm, -8,4 5,6 cm y -9,3 5,9 cm, respectivamente), aunque la diferencia fue mayor solo en S4 con respecto a S1 (p=0,014). Es posible que los períodos de recuperación entre cada S influyeron en el mantenimiento de la fuerza muscular explosiva (FME) durante los primeros 45-s de saltos, sin embargo, la suma de estas ejecuciones generó un aumento de la fatiga al final de la prueba. La FME puede ser afectada por la suma de ejecuciones de SVR aun con la inclusión de períodos cortos de recuperación entre series. La relación trabajo-recuperación en baloncesto es un factor que debe considerarse para planificar el entrenamiento en jugadores de baloncesto.

Impact studies from different factors on root development from Stevia rebaudiana bertoni

The demand for an alternative and a high potency sweetener to substitute sugar increases year in year out, more so as a high percentage of the world population becomes increasingly diabetic. The alternative natural sweetener at hand has been Stevia rebaudiana Bertoni, a plant species, native to Paraguay and a member of the family compositae. Stevia is usually propagated by stem cuttings due to low percentage (10 %) seed germination, thus limiting large scales cultivation. To cultivate this crop en mass therefore, there is need to evolve efficient rooting techniques. Influences of irradiation from light, and hormones on rooting have been reported. The rooting efficacy in stem cuttings of this crop under varying light wavelengths, dark and hormone factors was investigated. Evaluated parameters include- (i) day of root emergent, (ii) percentage of rooted cuttings, (iii) average number, (iv) length and (v) width, of roots. Analysis of variance at p<.05 revealed that the number, length and width, of roots differed significantly in each case at p<0.000. Light irradiation was highly effective and a necessary factor for rooting in stems cuttings of this crop. The red light-IBA combined factors served best in stem micro-cutting practice and facilitation of effective mass cultivation in stevia crop.

Análisis de salto vertical repetido en jugadores de baloncesto

Con el propósito de analizar los cambios de la fuerza máxima explosiva en relación a la ejecución de series de salto vertical repetido (SVR) con periodos cortos de recuperación pasiva en jugadores de baloncesto, se evaluaron 12 deportistas en un protocolo de cuatro series (S) de 15-s de saltos verticales con 10-s de recuperación entre S. Se midieron la altura de salto inicial (ASI) y final (ASF) de cada S; se utilizó ANOVA de una vía con post hoc de Bonferroni para el análisis de las diferencias ASF-ASI por S y una prueba t de Student para analizar el índice de fatiga (IF) por serie. Se encontró que la diferencia ASF-ASI fue progresivamente incremental desde la S1 hasta la S4 (-2,8 6,2 cm, -6,8 4,9 cm, -8,4 5,6 cm y -9,3 5,9 cm, respectivamente), aunque la diferencia fue mayor solo en S4 con respecto a S1 (p=0,014). Es posible que los períodos de recuperación entre cada S influyeron en el mantenimiento de la fuerza muscular explosiva (FME) durante los primeros 45-s de saltos, sin embargo, la suma de estas ejecuciones generó un aumento de la fatiga al final de la prueba. La FME puede ser afectada por la suma de ejecuciones de SVR aun con la inclusión de períodos cortos de recuperación entre series. La relación trabajo-recuperación en baloncesto es un factor que debe considerarse para planificar el entrenamiento en jugadores de baloncesto.

Peak areas and heights for minerals of ODP Leg 113-696B (Table 1)

Seismic data acquired over the eastern shelf and margin of the South Orkney microcontinent, Antarctica, have shown a high-amplitude reflection lying at a sub-bottom two-way traveltime (TWT) of 0.5-0.8 s. There appear to be two causes for the reflection which apply in different parts of the shelf. The more widespread cause of the reflection is a break-up unconformity associated with the opening of Jane Basin to the east. This is clearly seen where reflections in the underlying sequence are discordant. In contrast, in Eotvos Basin and the southeastern part of Bouguer Basin, the high-amplitude reflection in places cuts across bedding and is interpreted to be caused by silica diagenesis. A post-cruise analysis of core samples from Site 696 in Eotvos Basin by X-ray diffraction (XRD) and scanning electron microscopy (SEM) revealed the presence of a silica diagenetic front at 520-530 mbsf. The position of the unconformity at this site is uncertain, but probably coincides with a change of detrital input near 548 mbsf. Fluctuations of physical properties related to the depth of the diagenetic front are difficult to separate from those related to the variation of detrital composition over the same depth interval. Correlation of the drilling record with the seismic record is difficult but with a synthetic seismogram it is demonstrated that diagenesis is the probable cause of the high-amplitude reflection. In Bouguer Basin at Site 695 the depth of the high-amplitude reflection was not reached by drilling; however, the reflection is probably also caused by silica diagenesis because of the biogenic silica-rich composition of the sediments cored. The estimated temperatures and ages of the sediments at the depths of the high-amplitude reflections at Sites 695 and 696 compare favorably with similar data from other diagenetic fronts of the world. The high-amplitude reflection in Bouguer Basin is commonly of inverse polarity, possibly caused either by interference between reflections from several closely-spaced reflecting layers, such as chert horizons, or by free gas trapped near the diagenetic front.

Análisis empírico del tráfico en las autopistas de peaje radiales 3 y 5 de Madrid

El propósito de la presente investigación es determinar si, a través del estudio y análisis de los estudios de tráfico en autopistas de peaje, se pueden determinar las razones de los incumplimientos en las previsiones de estos estudios. La metodología se basa en un análisis empírico ex- post facto de los estudios de tráfico contenidos en los anteproyectos de las autopistas Radial 3 y Radial 5 y los datos realmente verificados. Tras una introducción para presentar las principales características de las autopistas de peaje, se realiza una revisión de la bibliografía sobre el cumplimiento de las previsiones de tráfico. Lo anterior permite establecer una serie de aspectos que pueden contribuir a estos incumplimientos, así como una serie de medidas encontradas para mejorar las futuras previsiones. Ya en el núcleo fundamental de la investigación, esta se centra en el análisis del cumplimiento de las previsiones de tráfico contenidas en los anteproyectos de la Radial 3 y Radial 5. Se realiza un análisis crítico de la metodología adoptada, así como de las variables e hipótesis realizadas. Tras este primer análisis, se profundiza en la fase de asignación de los estudios. Siempre con base a los tráficos reales y para el año 2006, se cuantifica el efecto en los incumplimientos, por un lado de las variables utilizadas, y por otro, del propio método ó curva de asignación. Finalmente, y con base en los hallazgos anteriores, se determinan una serie de limitaciones en el método de asignación de tráficos entre recorridos alternativos para el caso de entornos urbanos usado. El planteamiento con base a las teorías del agente racional y maximización de la utilidad esperada es criticado desde la perspectiva de la teoría de decisión bajo condiciones de riesgo planteada por Kahneman y Tversky. Para superar las limitaciones anteriores, se propone una nueva curva de asignación semi empírica que relaciona la proporción del tráfico que circula por la autopista de peaje con la velocidad media en la autovía libre alternativa. ABSTRACT The aim of this research is to confirm whether the forensic analysis of the traffic forecast studies for tolled highways may bring to light the reasons behind the lack of accuracy. The methodology used on this research is empirical and is based on the ex –post facto analysis of the real traffic numbers compared to the forecasted for the tolled highways Radial 3 and Radial 5. Firstly the main features of tolled highways are presented as an introductory chapter. Secondly a broad bibliographic search is presented, this is done from a global perspective and from the Spanish perspective too. From this review, a list of the main causes behind the systematic inaccuracy together with measures to improve future traffic forecast exercises are shown. In what we could consider as the core of the research, it focuses on the ratios of actual / forecast traffic for the tolled highways Radial 3 y Radial 5 in Madrid outskirts. From a critical perspective, the methodology and inputs used in the traffic studies are analysed. In a further step, the trip assignment stage is scrutinised to quantify the influence of the inputs and the assignment model itself in the accuracy of the traffic studies. This exercise is bases on the year 2006. Finally, the assignment model used is criticised for its application in tolled urban highways. The assumptions behind the model, rational agent and expected utility maximization theories, are questioned under the theories presented by Kahneman and Tversky (Prospect Theory). To overcome these assignment model limitations, the author presents a semi empiric new diversion curve. This curve links the traffic proportion using the tolled highway and the average speed in the toll free alternative highway.

Measuring skin temperature before, during and after exercise: a comparison of thermocouples and infrared thermography

Measuring skin temperature (TSK) provides important information about the complex thermal control system and could be interesting when carrying out studies about thermoregulation. The most common method to record TSK involves thermocouples at specific locations; however, the use of infrared thermal imaging (IRT) has increased. The two methods use different physical processes to measure TSK, and each has advantages and disadvantages. Therefore, the objective of this study was to compare the mean skin temperature (MTSK) measurements using thermocouples and IRT in three different situations: pre-exercise, exercise and post-exercise. Analysis of the residual scores in Bland-Altman plots showed poor agreement between the MTSK obtained using thermocouples and those using IRT. The averaged error was -0.75 °C during pre-exercise, 1.22 °C during exercise and -1.16 °C during post-exercise, and the reliability between the methods was low in the pre- (ICC = 0.75 [0.12 to 0.93]), during (ICC = 0.49 [-0.80 to 0.85]) and post-exercise (ICC = 0.35 [-1.22 to 0.81] conditions. Thus, there is poor correlation between the values of MTSK measured by thermocouples and IRT pre-exercise, exercise and post-exercise, and low reliability between the two forms of measurement.

Comportamiento mecánico de nuevas aleaciones de wolframio en función de la temperatura

La presente memoria de tesis tiene como objetivo principal la caracterización mecánica en función de la temperatura de nueve aleaciones de wolframio con contenidos diferentes en titanio, vanadio, itria y lantana. Las aleaciones estudiadas son las siguientes: W-0.5%Y2O3, W-2%Ti, W-2% Ti-0.5% Y2O3, W-4% Ti-0.5% Y2O3, W-2%V, W- 2%Vmix, W-4%V, W-1%La2O3 and W-4%V-1%La2O3. Todos ellos, además del wolframio puro se fabrican mediante compresión isostática en caliente (HIP) y son suministradas por la Universidad Carlos III de Madrid. La investigación se desarrolla a través de un estudio sistemático basado en ensayos físicos y mecánicos, así como el análisis post mortem de las muestras ensayadas. Para realizar dicha caracterización mecánica se aplican diferentes ensayos mecánicos, la mayoría de ellos realizados en el intervalo de temperatura de 25 a 1000 º C. Los ensayos de caracterización que se llevan a cabo son: • Densidad • Dureza Vicker • Módulo de elasticidad y su evolución con la temperatura • Límite elástico o resistencia a la flexión máxima, y su evolución con la temperatura • Resistencia a la fractura y su comportamiento con la temperatura. • Análisis microestructural • Análisis fractográfico • Análisis de la relación microestructura-comportamiento macroscópico. El estudio comienza con una introducción acerca de los sistemas en los que estos materiales son candidatos para su aplicación, para comprender las condiciones a las que los materiales serán expuestos. En este caso, el componente que determina las condiciones es el Divertor del reactor de energía de fusión por confinamiento magnético. Parece obvio que su uso en los componentes del reactor de fusión, más exactamente como materiales de cara al plasma (Plasma Facing Components o PFC), hace que estas aleaciones trabajen bajo condiciones de irradiación de neutrones. Además, el hecho de que sean materiales nuevos hace necesario un estudio previo de las características básicas que garantice los requisitos mínimos antes de realizar un estudio más complejo. Esto constituye la principal motivación de la presente investigación. La actual crisis energética ha llevado a aunar esfuerzos en el desarrollo de nuevos materiales, técnicas y dispositivos para la aplicación en la industria de la energía nuclear. El desarrollo de las técnicas de producción de aleaciones de wolframio, con un punto de fusión muy alto, requiere el uso de precursores de sinterizado para lograr densificaciones más altas y por lo tanto mejores propiedades mecánicas. Este es el propósito de la adición de titanio y vanadio en estas aleaciones. Sin embargo, uno de los principales problemas de la utilización de wolframio como material estructural es su alta temperatura de transición dúctil-frágil. Esta temperatura es característica de materiales metálicos con estructura cúbica centrada en el cuerpo y depende de varios factores metalúrgicos. El proceso de recristalización aumenta esta temperatura de transición. Los PFC tienen temperaturas muy altas de servicio, lo que facilita la recristalización del metal. Con el fin de retrasar este proceso, se dispersan partículas insolubles en el material permitiendo temperaturas de servicio más altas. Hasta ahora se ha utilizado óxidos de torio, lantano e itrio como partículas dispersas. Para entender cómo los contenidos en algunos elementos y partículas de óxido afectan a las propiedades de wolframio se estudian las aleaciones binarias de wolframio en comparación con el wolframio puro. A su vez estas aleaciones binarias se utilizan como material de referencia para entender el comportamiento de las aleaciones ternarias. Dada la estrecha relación entre las propiedades del material, la estructura y proceso de fabricación, el estudio se completa con un análisis fractográfico y micrográfico. El análisis fractográfico puede mostrar los mecanismos que están implicados en el proceso de fractura del material. Por otro lado, el estudio micrográfico ayudará a entender este comportamiento a través de la identificación de las posibles fases presentes. La medida del tamaño de grano es una parte de la caracterización microestructural. En esta investigación, la medida del tamaño de grano se llevó a cabo por ataque químico selectivo para revelar el límite de grano en las muestras preparadas. Posteriormente las micrografías fueron sometidas a tratamiento y análisis de imágenes. El documento termina con una discusión de los resultados y la compilación de las conclusiones más importantes que se alcanzan después del estudio. Actualmente, el desarrollo de nuevos materiales para aplicación en los componentes de cara al plasma continúa. El estudio de estos materiales ayudará a completar una base de datos de características que permita hacer una selección de ellos más fiable. The main goal of this dissertation is the mechanical characterization as a function of temperature of nine tungsten alloys containing different amounts of titanium, vanadium and yttrium and lanthanum oxide. The alloys under study were the following ones: W-0.5%Y2O3, W-2%Ti, W-2% Ti-0.5% Y2O3, W-4% Ti-0.5% Y2O3, W-2%V, W- 2%Vmix, W-4%V, W-1%La2O3 and W-4%V-1%La2O3. All of them, besides pure tungsten, were manufactured using a Hot Isostatic Pressing (HIP) process and they were supplied by the Universidad Carlos III de Madrid. The research was carried out through a systematic study based on physical and mechanical tests as well as the post mortem analysis of tested samples. Diverse mechanical tests were applied to perform this characterization; most of them were conducted at temperatures in the range 25-1000 ºC. The following characterization tests were performed: • Density • Vickers hardness • Elastic modulus • Yield strength or ultimate bending strength, and their evolution with temperature • Fracture toughness and its temperature behavior • Microstructural analysis • Fractographical analysis • Microstructure-macroscopic relationship analysis This study begins with an introduction regarding the systems where these materials could be applied, in order to establish and understand their service conditions. In this case, the component that defines the conditions is the Divertor of magnetic-confinement fusion reactors. It seems obvious that their use as fusion reactor components, more exactly as plasma facing components (PFCs), makes these alloys work under conditions of neutron irradiation. In addition to this, the fact that they are novel materials demands a preliminary study of the basic characteristics which will guarantee their minimum requirements prior to a more complex study. This constitutes the motivation of the present research. The current energy crisis has driven to join forces so as to develop new materials, techniques and devices for their application in the nuclear energy industry. The development of production techniques for tungsten-based alloys, with a very high melting point, requires the use of precursors for sintering to achieve higher densifications and, accordingly, better mechanical properties. This is the purpose of the addition of titanium and vanadium to these alloys. Nevertheless, one of the main problems of using tungsten as structural material is its high ductile-brittle transition temperature. This temperature is characteristic of metallic materials with body centered cubic structure and depends on several metallurgical factors. The recrystallization process increases their transition temperature. Since PFCs have a very high service temperature, this facilitates the metal recrystallization. In order to inhibit this process, insoluble particles are dispersed in the material allowing higher service temperatures. So far, oxides of thorium, lanthanum and yttrium have been used as dispersed particles. Tungsten binary alloys are studied in comparison with pure tungsten to understand how the contents of some elements and oxide particles affect tungsten properties. In turn, these binary alloys are used as reference materials to understand the behavior of ternary alloys. Given the close relationship between the material properties, structure and manufacturing process, this research is completed with a fractographical and micrographic analysis. The fractographical analysis is aimed to show the mechanisms that are involved in the process of the material fracture. Besides, the micrographic study will help to understand this behavior through the identification of present phases. The grain size measurement is a crucial part of the microstructural characterization. In this work, the measurement of grain size was carried out by chemical selective etching to reveal the boundary grain on prepared samples. Afterwards, micrographs were subjected to both treatment and image analysis. The dissertation ends with a discussion of results and the compilation of the most important conclusions reached through this work. The development of new materials for plasma facing components application is still under study. The analysis of these materials will help to complete a database of the features that will allow a more reliable materials selection.

Levantamento de ocorrência, alternativas de manejo, mecanismos de resistência e herança genética do capim-amargoso (Digitaria insularis) resistente ao herbicida glyphosate

O glyphosate é o principal herbicida utilizado no manejo de plantas daninhas na agricultura, aplicado em alguns sistemas de forma repetitiva ao longo de cada ano. Esta prática selecionou biótipos resistentes de espécies de plantas daninhas, sendo o capim-amargoso (Digitaria insularis) selecionado no Brasil. Portanto, se tornam necessários estudos para entender, manejar e reduzir a infestação do capim-amargoso resistente ao glyphosate. Dessa forma, esta pesquisa foi desenvolvida com os objetivos de: (i) mapear áreas do Brasil com possíveis infestações de capim-amargoso resistente ao glyphosate; (ii) avaliar alternativas químicas de seu manejo; (iii) elucidar os mecanismos de resistência ao glyphosate e; (iv) avaliar a herança genética dos genes que conferem resistência ao glyphosate. Para o desenvolvimento dos experimentos foram coletadas sementes de biótipos potencialmente resistentes de diversas regiões do Brasil onde ocorreram falhas de controle de D. insularis após a aplicação de glyphosate. Na primeira etapa da pesquisa foram realizados experimentos para determinação de uma dose discriminatória de triagementre as populações resistentes e suscetíveis ao glyphosate, através de curvas de dose-resposta, para identificar a resistência ao Glyphosate, sendo que estes dados foram utilizados para mapear a ocorrência de biótipos resistentes em algumas regiões do país. Na segunda etapa foi conduzido um experimento em casa-de-vegetação visando encontrar herbicidas alternativos ao Glyphosate para controle do capim-amargoso, utilizando herbicidas recomendados para as culturas do milho e algodão, tanto em condições de aplicação de pré como em pós-emergência da planta daninha. Na terceira etapa foram realizados ensaios para determinar a existência de absorção e translocação diferencial do glyphosate em biótipos suscetíveis e resistentes, juntamente com a análise molecular para comparar a região 106 do gene que codifica a EPSPs nestes biótipos. Por fim um estudo de polinização cruzada foi conduzido para avaliar se genes de resistência ao glyphosate são transferidos para a geração seguinte após inflorescências de biótipos suscetíveis serem acondicionadas com as de biótipos resistentes, submetendo a geração seguinte a experimentos de curva de dose-resposta com o glyphosate. Através do modelo de curva dose-resposta do programa estatístico R, determinou-se a dose de 960 g e.a ha-1, como a dose utilizada para triagem dos biótipos oriundos de diferentes regiões do Brasil. Com isto foram gerados mapas indicando a presença ou ausência de resistência ao herbicida, sendo que as região oeste do Paraná e sul do Mato Grosso do Sul apresentam maior número de localidades com a presença de biótipos resistentes. As alternativas de controle viáveis como pós-emergentes no estádio de um a dois perfilhos, foram os herbicidas Nicosulfuron, Imazapic + Imazapyr, Atrazine, Haloxifop-methyl e Tepraloxydim. Na pré-emergência do capim-amargoso os herbicidas Atrazine, Isoxaflutole, S-metolachlor, Clomazone, Diuron e Flumioxazin se apresentaram como eficazes para o controle desta espécie. Os resultados do experimento de absorção, translocação e comparação da região 106 não mostraram diferenças entre os biótipos resistente e suscetível. O experimento sobre cruzamento entre biótipos resistente e suscetível determinou a espécie D. insularis como autógama e sem transferência de genes que causam a resistência ao glyphosate.

Sistema especialista para análise pós-evento da proteção em subestações distribuidoras.

É importante que as redes elétricas tenham altos índices de confiabilidade, de forma a se manter a agilidade e a manutenção ideais para um melhor funcionamento. Por outro lado, o crescimento inesperado da carga, falhas em equipamentos e uma parametrização inadequada das funções de proteção tornam a análise de eventos de proteção mais complexas e demoradas. Além disso, a quantidade de informações que pode ser obtida de relés digitais modernos tem crescido constantemente. Para que seja possível uma rápida tomada de decisão e manutenção, esse projeto de pesquisa teve como objetivo a implementação de um sistema completo de diagnóstico que é ativado automaticamente quando um evento de proteção ocorrer. As informações a serem analisadas são obtidas de uma base de dados e de relés de proteção, via protocolo de comunicação IEC 61850 e arquivos de oscilografia. O trabalho aborda o sistema Smart Grid completo incluindo: a aquisição de dados nos relés, detalhando o sistema de comunicação desenvolvido através de um software com um cliente IEC61850 e um servidor OPC e um software com um cliente OPC, que é ativado por eventos configurados para dispará-lo (por exemplo, atuação da proteção); o sistema de pré-tratamento de dados, onde os dados provenientes dos relés e equipamentos de proteção são filtrados, pré-processados e formatados; e o sistema de diagnóstico. Um banco de dados central mantém atualizados os dados de todas essas etapas. O sistema de diagnóstico utiliza algoritmos convencionais e técnicas de inteligência artificial, em particular, um sistema especialista. O sistema especialista foi desenvolvido para lidar com diferentes conjuntos de dados de entrada e com uma possível falta de dados, sempre garantindo a entrega de diagnósticos. Foram realizados testes e simulações para curtos-circuitos (trifásico, dupla-fase, dupla-fase-terra e fase-terra) em alimentadores, transformadores e barras de uma subestação. Esses testes incluíram diferentes estados do sistema de proteção (funcionamento correto e impróprio). O sistema se mostrou totalmente eficaz tanto no caso de disponibilidade completa quanto parcial de informações, sempre fornecendo um diagnóstico do curto-circuito e analisando o funcionamento das funções de proteção da subestação. Dessa forma, possibilita-se uma manutenção muito mais eficiente pelas concessionárias de energia, principalmente no que diz respeito à prevenção de defeitos em equipamentos, rápida resposta a problemas, e necessidade de reparametrização das funções de proteção. O sistema foi instalado com sucesso em uma subestação de distribuição da Companhia Paulista de Força e Luz.

Cerebral Microembolization During Aortic Valve Replacement Using Minimally Invasive or Conventional Extracorporeal Circulation: A Randomized Trial.

To compare intraoperative cerebral microembolic load between minimally invasive extracorporeal circulation (MiECC) and conventional extracorporeal circulation (CECC) during isolated surgical aortic valve replacement (SAVR), we conducted a randomized trial in patients undergoing primary elective SAVR at a tertiary referral hospital. The primary outcome was the procedural phase-related rate of high-intensity transient signals (HITS) on transcranial Doppler ultrasound. HITS rate was used as a surrogate of cerebral microembolism in pre-defined procedural phases in SAVR using MiECC or CECC with (+F) or without (-F) an oxygenator with integrated arterial filter. Forty-eight patients were randomized in a 1:1 ratio to MiECC or CECC. Due to intraprocedural Doppler signal loss (n = 3), 45 patients were included in final analysis. MiECC perfusion regimen showed a significantly increased HITS rate compared to CECC (by a factor of 1.75; 95% confidence interval, 1.19-2.56). This was due to different HITS rates in procedural phases from aortic cross-clamping until declamping [phase 4] (P = 0.01), and from aortic declamping until stop of extracorporeal perfusion [phase 5] (P = 0.05). Post hoc analysis revealed that MiECC-F generated a higher HITS rate than CECC+F (P = 0.005), CECC-F (P = 0.05) in phase 4, and CECC-F (P = 0.03) in phase 5, respectively. In open-heart surgery, MiECC is not superior to CECC with regard to gaseous cerebral microembolism. When using MiECC for SAVR, the use of oxygenators with integrated arterial line filter appears highly advisable. Only with this precaution, MiECC confers a cerebral microembolic load comparable to CECC during this type of open heart surgery.

WOMAC 20, 50, 70 response levels in patients treated with Rofecoxib for osteoarthritis

Aim of study: The goal of this post-hoc analysis was to examine the difference between treatment groups when varying the target response level from at least a 20% improvement from baseline, to at least 50% and 70% improvements in Phase III studies of rofecoxib in patients with osteoarthritis. Methods: The analysis focused on results from two 6-week, placebo-controlled, ibuprofen-comparator, Phase III osteoarthritis studies. These studies employed a flare design requiring a minimum level of symptoms at entry following discontinuation of prior analgesics. Two definitions of ‘‘patient improved’’ from baseline were used: (1) WOMAC-P: a reduction in the WOMAC pain score and (2) WOMAC-PFS: a reduction in the WOMAC pain score and either a reduction in the WOMAC stiffness or function score. The improvement target was increased from 20% to 50% to 70%, relative to baseline, to investigate how the increase affects the ability to detect the differences between treatment groups. Analyses were conducted on the average and last of all measurements collected during a 6-week treatment period. Results: In the ibuprofen-comparator studies, 1545 patients were randomized to placebo, rofecoxib 12.5 mg once daily, rofecoxib 25 mg once daily, and ibuprofen 800 mg three times daily in a 1:3:3:3 ratio. The percentages of patients who met the improvement targets decrease as the target increases from 20% to 50% to 70%. There were meaningful differences between the active treatment and placebo that were inversely related to the improvement target. For example, there was a 31 (P ! 0.001), 21 (P ! 0.001), and 12 (P ! 0.001) percentage-point difference between rofecoxib 25 mg and placebo for the 20%, 50%, and 70% targets for WOMAC-P. For WOMAC-PFS, the differences between rofecoxib 25 mg and placebo were 33 (P ! 0.001), 18 (P ! 0.001), and 9 (P ! 0.01) percentage points for the 20%, 50%, and 70% improvement targets. Conclusions: Meaningful differences between active treatments and placebo were detected at all three response levels associated with the WOMAC-P and WOMAC-PFS endpoints. The differences between groups were more dramatic at the 20% and 50% response levels. The WOMAC (20,50,70)-P and WOMAC (20,50,70)-PFS endpoints further confirm, at an individual patient level, the clinical benefit of rofecoxib in the treatment of osteoarthritis that was previously reported as a difference in means.

Microanalysis of quenched and self-extinguished aluminium rods burned in oxygen

Promoted ignition tests and quench tests have been conducted and analysed for 3.2 mm aluminum rods in 99.995% oxygen. Tests have been conducted in oxygen pressures varying from 538 kPa to 773 kPa. Samples that self-extinguished or were quenched were selected for further analysis. The microstructure of the selected samples were analysed by electron microscopy, using energy dispersive spectrometry and electron back-scatter techniques, to identify and visualize, respectively, the species present. The grain structures of these samples were etched, viewed and photographed under polarized light by an optical microscope. From the micrographs produced by the post-test analysis, clearly defined boundaries between the oxide and the melted and resolidified metal have been observed. In both the melted and resolidified metal and the oxide layer, significant numbers of gas bubbles, solid inclusions and several diffuse oxide bubbles have been captured during the cooling process. It is concluded that convective movement is occurring within the molten drop and that analysis of quenched samples provides more useful information on the state of the burning droplet than samples allowed to cool slowly to room temperature. Recommendations are made regarding future investigations into aluminum burning, focusing on the transport of reactants through the liquid oxide layer.

Risk homeostasis theory in simulated environments

This thesis has two aims. First, it sets out to develop an alternative methodology for the investigation of risk homeostasis theory (RHT). It is argued that the current methodologies of the pseudo-experimental design and post hoc analysis of road-traffic accident data both have their limitations, and that the newer 'game' type simulation exercises are also, but for different reasons, incapable of testing RHT predictions. The alternative methodology described here is based on the simulation of physical risk with intrinsic reward rather than a 'points pay-off'. The second aim of the thesis is to examine a number of predictions made by RHT through the use of this alternative methodology. Since the pseudo-experimental design and post hoc analysis of road-traffic data are both ill-suited to the investigation of that part of RHT which deals with the role of utility in determining risk-taking behaviour in response to a change in environmental risk, and since the concept of utility is critical to RHT, the methodology reported here is applied to the specific investigation of utility. Attention too is given to the question of which behavioural pathways carry the homeostasis effect, and whether those pathways are 'local' to the nature of the change in environmental risk. It is suggested that investigating RHT through this new methodology holds a number of advantages and should be developed further in an attempt to answer the RHT question. It is suggested too that the methodology allows RHT to be seen in a psychological context, rather than the statistical context that has so far characterised its investigation. The experimental findings reported here are in support of hypotheses derived from RHT and would therefore seem to argue for the importance of the individual and collective target level of risk, as opposed to the level of environmental risk, as the major determinant of accident loss.

Structural behaviour of glass reinforced plastics

The aim of this research is to promote the use of G.R.P. as a structural material. In the past, the use of G.R.P. has been confined to non-load carrying applications. Such uses are still rapidly increasing but in addition significant changes have been made during the last decade in the development of semi-structural and now even fully structural applications. Glass-reinforced plastic is characterized by a high strength but a relatively low modulus of elasticity. For this reasona G.R.P. structure can expect to show large deformations as a result of which the individual structural members will fail under load due to a loss of stability rather than approaching the ultimate strength of the material. For this reason the selection of the geometrical shapes of G.R.P. structural elements is considered to be an important factor in designing G.R.P. structures. The first chapter of this thesis deals with a general review of the theoretical and experimental methods used to describe the structural properties of G.R.P. The research programme includes five stages dealing with the structural behaviour of G.R.P. The first stage (Chapter 2) begins with selecting and designing an optimum box beam cross-section which gives the maximum flexural and torsional rigidity. The second stage of investigation (Chapter 3) deals with beam to beam connections. A joint was designed and manufactured with different types of fasteners used to connect two beam units. A suitable fastener was selected and the research extended to cover the behaviour of long span beams using multiple joints. The third part of the investigation includes a study of the behaviour of box beams subjected to combined bending, shear and torsion. A special torque rig was developed to perform the tests. Creep deformation of 6 m span G.R.P. was investigated as the fourth stage under a range of loading conditions. As a result of the phenomenon of post buckling behaviour exhibited in the compression flange during testing of box beams during earlier stages of the investigation it was decided to consider this phenomenon in more detail in the final stage of the investigation. G.R.P. plates with different fibre orientation were subjected to uniaxial compression and tested up to failure. In all stages of the investigation theoretical predictions and experimental results were compared and generally good correlation between theory and experimental data was observed.