797 resultados para countermovement jump


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Os controladores de caudal, normalmente implementados em sistemas Supervisory control and data acquisition (SCADA), apresentam uma grande relevância no controlo automático de canais de adução. Para garantir que os controladores de caudal sejam fiáveis em todo o seu domínio de funcionamento (em situações de escoamento com ressalto livre ou submerso e de transição entre escoamentos com ressalto livre e ressalto submerso) foram comparados os resultados dos ensaios experimentais com diferentes métodos de cálculo da vazão em comportas e/ou sobre soleiras. O programa de ensaios foi realizado nos canais laboratorial e experimental da Universidade de Évora. Foram realizados ensaios em comportas planas verticais e em soleiras do tipo Waterways Experiment Station (WES) controladas ou não por comportas planas verticais. Em ambos os casos, foram contempladas as situações de escoamento com ressalto livre e submerso. Os resultados obtidos mostram que: a) para as comportas, o método Rajaratnam e Subramanya (1967a) conduz a bons resultados com um erro percentual médio absoluto MAPE < 1% para o escoamento com ressalto livre e MAPE < 4% para o submerso; a transição entre escoamentos foi identificada corretamente por este método; b) para as soleiras, obtiveram-se bons resultados para o escoamento com ressalto livre para o método USACE (1987), com MAPE < 2%, e para o submerso através do método Alves e Martins (2011), com MAPE < 5%; a transição entre escoamentos pode ser considerada adequada de acordo com a curva experimental de Grace (1963); c) para soleiras controladas por comporta, conseguiram-se bons resultados para o escoamento com ressalto livre recorrendo à equação dos orifícios de pequenas dimensões, com MAPE < 1, 5%, e para o submerso com a equação dos orifícios totalmente submersos com MAPE < 1, 6%; em ambos os casos foi necessária calibração do coeficiente de vazão; a transição entre escoamentos foi adequada pelo método de Grace (1963). Com base nos resultados obtidos, foi possível definir um algoritmo de vazão generalizado para comportas e/ou soleiras que permite a determinação da vazão para as situações de escoamento com ressalto livre e submerso incluindo a transição entre escoamentos; ABSTRACT: Flow controllers, usually implemented in Supervisory Control and Data Acquisition (SCADA) systems, are very important in the automatic control of irrigation canal systems. To ensure that flow controllers are reliable for the entire operating range (free or submerged flow and flow transitions) the experimental results were compared with different methods of flow measurement for gates and/or weirs. The test program was conducted in the laboratory flume and in the automatic canal of the University of ´Evora. Tests were carried in sluice gates and in broad-crested weirs controlled or not by sluice gate. In both cases free and submerged flow conditions were analyzed. The results show that: a) for the sluice gates, the method of Rajaratnam e Subramanya (1967a) leads to good results with a mean absolute percentage error (MAPE) < 1% for free flow and MAPE < 4% for submerged flow. The transition between flows is correctly identified by this method; b) for the uncontrolled weir, good results were obtained for free flow with the method USACE (1987) with MAPE < 2%, and for submerged flow by the method Alves e Martins (2011) with MAPE < 5%. The transition between flows can be accurately defined by the experimental curve of Grace (1963); c) for the controlled weir, good results were achieved for the free flow with the small orifice equation with MAPE < 1.5% and for submerged flow with the submerged orifice equation with MAPE < 1.6%; in both cases the calibration of the discharge coefficient is needed. The transition between flows can be accomplished through Grace (1963) method. Based on the obtained results, it was possible to define a generalized flow algorithm for gates and/or weirs that allows flow determination for free and submerged flow conditions including the transition between flows.

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Determining effective hydraulic, thermal, mechanical and electrical properties of porous materials by means of classical physical experiments is often time-consuming and expensive. Thus, accurate numerical calculations of material properties are of increasing interest in geophysical, manufacturing, bio-mechanical and environmental applications, among other fields. Characteristic material properties (e.g. intrinsic permeability, thermal conductivity and elastic moduli) depend on morphological details on the porescale such as shape and size of pores and pore throats or cracks. To obtain reliable predictions of these properties it is necessary to perform numerical analyses of sufficiently large unit cells. Such representative volume elements require optimized numerical simulation techniques. Current state-of-the-art simulation tools to calculate effective permeabilities of porous materials are based on various methods, e.g. lattice Boltzmann, finite volumes or explicit jump Stokes methods. All approaches still have limitations in the maximum size of the simulation domain. In response to these deficits of the well-established methods we propose an efficient and reliable numerical method which allows to calculate intrinsic permeabilities directly from voxel-based data obtained from 3D imaging techniques like X-ray microtomography. We present a modelling framework based on a parallel finite differences solver, allowing the calculation of large domains with relative low computing requirements (i.e. desktop computers). The presented method is validated in a diverse selection of materials, obtaining accurate results for a large range of porosities, wider than the ranges previously reported. Ongoing work includes the estimation of other effective properties of porous media.

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Doutoramento em Gestão

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Dissertação de Mestrado para obtenção do grau de Mestre em Design de Comunicação, apresentada na Universidade de Lisboa - Faculdade de Arquitectura.

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World War II profoundly impacted Florida. The military geography of the State is essential to an understanding the war. The geostrategic concerns of place and space determined that Florida would become a statewide military base. Florida’s attributes of place such as climate and topography determined its use as a military academy hosting over two million soldiers, nearly 15 percent of the GI Army, the largest force theUS ever raised. One-in-eight Floridians went into uniform. Equally,Florida’s space on the planet made it central for both defensive and offensive strategies. The Second World War was a war of movement, and Florida was a major jump off point forUSforce projection world-wide, especially of air power. Florida’s demography facilitated its use as a base camp for the assembly and engagement of this military power. In 1940, less than two percent of the US population lived in Florida, a quiet, barely populated backwater of the United States.[1] But owing to its critical place and space, over the next few years it became a 65,000 square mile training ground, supply dump, and embarkation site vital to the US war effort. Because of its place astride some of the most important sea lanes in the Atlantic World,Florida was the scene of one of the few Western Hemisphere battles of the war. The militarization ofFloridabegan long before Pearl Harbor. The pre-war buildup conformed to theUSstrategy of the war. The strategy of theUS was then (and remains today) one of forward defense: harden the frontier, then take the battle to the enemy, rather than fight them inNorth America. The policy of “Europe First,” focused the main US war effort on the defeat of Hitler’sGermany, evaluated to be the most dangerous enemy. In Florida were established the military forces requiring the longest time to develop, and most needed to defeat the Axis. Those were a naval aviation force for sea-borne hostilities, a heavy bombing force for reducing enemy industrial states, and an aerial logistics train for overseas supply of expeditionary campaigns. The unique Florida coastline made possible the seaborne invasion training demanded for USvictory. The civilian population was employed assembling mass-produced first-generation container ships, while Floridahosted casualties, Prisoners-of-War, and transient personnel moving between the Atlantic and Pacific. By the end of hostilities and the lifting of Unlimited Emergency, officially on December 31, 1946, Floridahad become a transportation nexus. Florida accommodated a return of demobilized soldiers, a migration of displaced persons, and evolved into a modern veterans’ colonia. It was instrumental in fashioning the modern US military, while remaining a center of the active National Defense establishment. Those are the themes of this work. [1] US Census of Florida 1940. Table 4 – Race, By Nativity and Sex, For the State. 14.

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UNLABELLED Since its discovery in the early 2000s, methicillin-resistant Staphylococcus aureus (MRSA) clonal complex 398 (CC398) has become a rapidly emerging cause of human infections, most often associated with livestock exposure. We applied whole-genome sequence typing to characterize a diverse collection of CC398 isolates (n = 89), including MRSA and methicillin-susceptible S. aureus (MSSA) from animals and humans spanning 19 countries and four continents. We identified 4,238 single nucleotide polymorphisms (SNPs) among the 89 core genomes. Minimal homoplasy (consistency index = 0.9591) was detected among parsimony-informative SNPs, allowing for the generation of a highly accurate phylogenetic reconstruction of the CC398 clonal lineage. Phylogenetic analyses revealed that MSSA from humans formed the most ancestral clades. The most derived lineages were composed predominantly of livestock-associated MRSA possessing three different staphylococcal cassette chromosome mec element (SCCmec) types (IV, V, and VII-like) including nine subtypes. The human-associated isolates from the basal clades carried phages encoding human innate immune modulators that were largely missing among the livestock-associated isolates. Our results strongly suggest that livestock-associated MRSA CC398 originated in humans as MSSA. The lineage appears to have undergone a rapid radiation in conjunction with the jump from humans to livestock, where it subsequently acquired tetracycline and methicillin resistance. Further analyses are required to estimate the number of independent genetic events leading to the methicillin-resistant sublineages, but the diversity of SCCmec subtypes is suggestive of strong and diverse antimicrobial selection associated with food animal production. IMPORTANCE Modern food animal production is characterized by densely concentrated animals and routine antibiotic use, which may facilitate the emergence of novel antibiotic-resistant zoonotic pathogens. Our findings strongly support the idea that livestock-associated MRSA CC398 originated as MSSA in humans. The jump of CC398 from humans to livestock was accompanied by the loss of phage-carried human virulence genes, which likely attenuated its zoonotic potential, but it was also accompanied by the acquisition of tetracycline and methicillin resistance. Our findings exemplify a bidirectional zoonotic exchange and underscore the potential public health risks of widespread antibiotic use in food animal production.

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Introduction. Test of Everyday Attention for Children (TEA-Ch) has been validated in different countries demonstrating that it is an instrument with a correct balance between reliability and duration. Given the shortage of trustworthy instruments of evaluation in our language for infantile population we decide to explore the Spanish version of the TEA-Ch. Methods. We administered TEA-Ch (version A) to a sample control of 133 Spanish children from 6 to 11 years enrolled in school in the Community of Madrid. Four children were selected at random by course of Primary Education, distributing the sex of equivalent form. Descriptive analysis and comparison by ages and sex in each of the TEA-Ch's subtests were conducted to establish a profile of the sample. In order to analyze the effect of the age, subjects were grouped in six sub-samples: 6, 7, 8, 9, 10 and 11 years-old. Results. This first descriptive analysis demonstrates age exerted a significant effect on each measure, due to an important "jump" in children's performance between 6 and 7 years-old. The effect of sex was significant only in two visual attention measures (Sky Search & Map) and interaction age and sex exerted a significant effect only in the dual task (Score DT). Conclusions. The results suggest that the Spanish version of the TEA-Ch (A) might be a useful instrument to evaluate attentional processes in Spanish child population.

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The Eemian (last interglacial, 130-115 ka) was likely the warmest of all interglacials of the last 800 ka, with summer Arctic temperatures 3-5 degrees C above present. Here, we present improved Eemian climate records from central Greenland, reconstructed from the base of the Greenland Ice Sheet Project 2 (GISP2) ice core. Our record comes from clean, stratigraphically disturbed, and isotopically warm ice from 2,750 to 3,040 m depth. The age of this ice is constrained by measuring CH_4 and delta O^18 of O_2, and comparing with the historical record of these properties from the North Greenland Ice Core Project (NGRIP) and North Greenland Eemian Ice Drilling (NEEM) ice cores. The d^18 O_ice, d^15N of N_2, and total air content for samples dating discontinuously from 128 to 115 ka indicate a warming of similar to 6 degrees C between 127-121 ka, and a similar elevation history between GISP2 and NEEM. The reconstructed climate and elevation histories are compared with an ensemble of coupled climate-ice-sheet model simulations of the Greenland ice sheet. Those most consistent with the reconstructed temperatures indicate that the Greenland ice sheet contributed 5.1 m (4.1-6.2 m, 95% credible interval) to global eustatic sea level toward the end of the Eemian. Greenland likely did not contribute to anomalously high sea levels at ~127 ka, or to a rapid jump in sea level at ~120 ka. However, several unexplained discrepancies remain between the inferred and simulated histories of temperature and accumulation rate at GISP2 and NEEM, as well as between the climatic reconstructions themselves.

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Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em Fisioterapia

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Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em Fisioterapia

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El objetivo del presente estudio fue analizar los cambios en el rendimiento en función de dos métodos de entrenamiento, el desarrollado mediante electro-estimulación muscular integral (EMI) frente a otro en el que se utilizaron bandas elásticas y que denominamos entrenamiento funcional con elásticos (EFE). La muestra estuvo compuesta por un grupo de diez (N=10) personas físicamente activas (23,04 ± 2,5 años). Se utilizó un diseño cuasi-experimental con medidas pre-post. Y fueron analizados los resultados de las pruebas: salto vertical con ayuda de brazos; y velocidad de desplazamiento en una carrera de ida y vuelta de 12 metros de distancia (6+6). Se realizó un análisis descriptivo de casos y medias. Y dado el tamaño de la muestra se calculó el tamaño del efecto, el cual fue bajo o moderado (d<0,5). Por último se compararon las diferencias de las medias de los grupos mediante la U de Mann Whitney, y las diferencias de las medias en función del tiempo (pre-post) mediante Friedman; en ambos casos los resultados no fueron significativos (p<0,5). En cuanto a los valores descriptivos del pre-post en ambos grupos: el grupo que entrenó con bandas elásticas obtuvo mejores resultados en ambas pruebas que el grupo que entrenó con EMI. En conclusión, el entrenamiento con bandas elásticas, a pesar de no ser significativo, parece mostrarse más efectivo que el entrenamiento con electro-estimulación muscular integral. Si bien, dadas las limitaciones del estudio estos datos hay que tomarlos con la pertinente cautela.

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El presente estudio analizó los efectos de un entrenamiento pliométrico y de un entrenamiento resistido mediante arrastres de trineo de 8 semanas de duración sobre el rendimiento en pruebas de salto vertical (SJ y CMJ) y velocidad en esprint de 30 metros (tiempo parcial en 10m) en futbolistas amateurs. El estudio incluyó dos grupos experimentales que realizaron uno de los dos métodos de entrenamiento y un grupo de control. Participaron en el diseño final 26 jugadores de futbol con una media de edad de 21,38 ± 2,53 años, una altura media de 177,22 ± 6,19 cm y una media de peso corporal de 78,78 ± 12,13 kg. El programa de entrenamiento constaba de dos días de entrenamiento para los grupos de pliometría y entrenamiento resistido respectivamente, que realizaron durante 8 semanas consecutivas con una carga diferente entre las 4 primeras semanas y las 4 últimas aumentando el peso en el trineo de arrastre y la altura y distancia entre vallas. El análisis estadístico no muestra diferencias significativas entre grupos después de las 8 semanas de entrenamiento, sin embargo, en el análisis descriptivo si se aprecian cambios positivos a nivel de rendimiento tanto en salto vertical como en el esprint.

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Objetivo: Determinar la distribución por percentiles de salto con contramovimiento (CMJ) en una población escolar de Bogotá, Colombia, perteneciente al estudio Fuprecol. Métodos: Estudio transversal realizado entre 2846 niños y 2754 adolescentes, entre 9 a 17 años de edad, pertenecientes a 18 instituciones educativas oficiales de Bogotá, Colombia. Se evaluó el CMJ, de acuerdo, con lo establecido por la batería de condición física, Fuprecol. Se calcularon, los percentiles (P3, P10, P25, P50, P75, P90 y P97), y curvas centiles por el método LMS, según su sexo y edad. Se realizó una comparación entre los valores de la CMJ observados con estándares internacionales. Resultados: La muestra estuvo constituida por 5.600 niños y adolescentes entre 9 y 17 años; el promedio de edad fue 12,6 ± 2,4 años. En el CMJ, los valores altos, los obtuvieron los niños, franja en la que la media osciló entre 25,1 cm a los 9 años, y 38,6 cm a los 17; para las niñas, la media fluctuó entre 23,2 cm a los 9 años, y 28,6 a los 17; en ambos sexos esos valores aumentan proporcional a la edad. Conclusiones: Se registran percentiles del CMJ de acuerdo con la edad y el sexo, que podrán ser usados como referencia en la evaluación del salto vertical desde edades tempranas.

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Objetivo: Estimar la relación entre indicadores de desempeño muscular y estado nutricional con la velocidad/agilidad, en una muestra de escolares de instituciones educativas del Distrito de Bogotá, Colombia, perteneciente al estudio FUPRECOL. Materiales y Métodos: estudio transversal, en 2803 niños y 3952 niñas (58.5 %), entre 9 y 17 años de edad, pertenecientes a 24 instituciones educativas del sector oficial, en Bogotá, Colombia. La velocidad/agilidad se evaluó con la prueba de carrera de ida y vuelta 4x10 m y los indicadores de fuerza muscular fueron medidos por medio de fuerza prensil, salto longitudinal. Las asociaciones se estimaron por medio de regresión logística binaria. Resultados: el 74.6 % de las mujeres y el 68.6 % de los varones mostraron bajos niveles de velocidad/agilidad; en mujeres, el modelo de regresión logística binario se observa que aquellas que tener bajos niveles de velocidad/agilidad se asociaba con obesidad (OR 2.25 IC 95 % 1.53-3.11), sobrepeso (OR 1.43 IC 95 % 1.19-1.72), bajos niveles de salto longitudinal (OR 2.06 IC 95 % 1.73-2.44) y tener valores de fuerza prensi no saludable (OR 1.45 IC 95 % 1.25-1.88). En hombres, tener entre 9-12 años, (OR 1.89 IC 95% 1.53-2.53), padecer de sobrepeso (OR 2.11 IC 95% 1.63-2.74) u obesidad (OR 3.00 IC 95% 2.03-4.43), se asoció con bajos niveles de velocidad/agilidad. Conclusión: se encontró que un alto porcentaje de la muestra estudiada tiene bajos niveles de velocidad/agilidad; adicionalmente, se observó una fuerte relación entre los indicadores de adiposidad y desempeño muscular, con los niveles de velocidad/agilidad. Se sugiere la implementación de programas escolares, que contrarresten la aparición de manifestaciones de riesgo cardiometabólico.