Charged rotating black holes in higher dimensions

We use a recent implementation of the large $D$ expansion in order to construct the higher-dimensional Kerr-Newman black hole and also new charged rotating black bar solutions of the Einstein-Maxwell theory, all with rotation along a single plane. We describe the space of solutions, obtain their quasinormal modes, and study the appearance of instabilities as the horizons spread along the plane of rotation. Generically, the presence of charge makes the solutions less stable. Instabilities can appear even when the angular momentum of the black hole is small, as long as the charge is sufficiently large. We expect that, although our study is performed in the limit $D\to\infty$, the results provide a good approximation for charged rotating black holes at finite $D\geq 6$.Comment: 21 pages, 1 figur

Efeitos da vibração corporal no equilíbrio em idosos: uma revisão de literatura

Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em FisioterapiaObjectivo: Sumariar a actual evidência da vibração corporal no equilíbrio em indivíduos idosos, contribuindo para a sistematização do conhecimento sobre esta temática. Metodologia: Pesquisa computorizada nas bases de dados PubMed, Web of Knowledge e PEDro, de modo a seleccionar estudos randomizados controlados com avaliação sobre o efeito da vibração corporal no equilíbrio em idosos. Resultados: Foram incluídos 11 artigos, apresentando uma qualidade média de 5,55 em 10 na escala de PEDro. Os artigos seleccionados para este estudo utilizaram 3 diferentes plataformas de vibração, sendo que 5 dos referidos artigos utilizaram a plataforma vibratória da marca Galileo (vibração sinusoidal alternada), 5 utilizaram a plataforma vibratória da marca Power-Plate (vibração vertical sincronizada) e 1 utilizou um protótipo de uma plataforma vibratória, Sea-saw (vibração sinusoidal alternada). Conclusões: A vibração corporal parece ter um efeito positivo na melhoria do equilíbrio em idosos, podendo eventualmente contribuir para a prevenção de quedas e consequentemente na melhoria da qualidade de vida. Este método aparenta ser uma alternativa viável para pacientes idosos, independentemente da idade. Objective: To summarize the present evidence of body vibration in the balance of elderly people, therefore contributing to the systematization of our knowledge of this subject. Methods: Computer research in PubMed, Web of Knowledge and PEDro data bases, in order to select randomizes controlled trials with the evaluation of body vibration in the balance of the elderly. Results: 11 articles were considered, presenting an average quality of 5,55 in 10, regarding the PEDro scale. The selected articles for this study used 3 different vibrating platforms, 5 of the above mentioned articles used the vibrating platform brand Galileo (alternated sinusoidal vibration), other 5 used the vibrating platform brand Power-Plate (synchronized vertical vibration) and 1 used a vibrating platform prototype brand Sea-saw (alternated sinusoidal vibration). Conclusions: Body vibration seems to achieve a beneficial effect in improving balance in elderly people, eventually contributing to fall´s prevention and consequently improving life quality. This method seems to be a viable alternative for elderly patients, regardless of their age

Investigating the 'latent' deficit hypothesis : age at time of head injury, executive and implicit functions and behavioral insight

This study investigated the 'latent deficit' hypothesis in two groups of frontotemporal headinjured patients, those injured prior to steep morphological and corresponding functional maturational periods for frontotemporal networks (≤ age 25), and those injured >28 years. The latent deficit hypothesis proposes that early injuries produce enduring cognitive deficits manifest later in the lifespan with graver consequences for behavior than adult injuries, particularly after frontal pathology (Eslinger, Grattan, Damasio & Damasio, 1992). Implicit and executive deficits both contribute to behavioral insight after frontotemporal head injury (Barker, Andrade, Romanowski, Morton & Wasti, 2006). On the basis of morphological and behavioral data, we hypothesised that early injury would confer greater vulnerability to impairment on tasks associated with frontotemporal regions than later injury. Patients completed experimental tasks of implicit cognition, executive function measures and the DEX measure of behavioural insight (Behavioral Assessment of the Dysexecutive Syndrome: Wilson, Alderman, Burgess, Emslie, & Evans, 1996). The Early Injury group were more impaired on implicit cognition tasks compared to controls that Late Injury patients. There were no marked group differences on most executive function measures. Executive ability only contributed to behavioral awareness in the Early Injury Group. Findings showed that age at injury moderates the relationship between executive and implicit cognition and behavioral insight and that early injuries result in longstanding deficits to functions associated with frontotemporal regions partially supporting the latent deficit hypothesis

Metamateriales sub-longitud de onda para microdispositivos fotónicos de altas prestaciones

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, leída el 28-04-2020Photonics has become of paramount importance in many areas of our everyday life owing to its inherent potential to develop not only telecom and datacom solutions, but also many other applications such as metrology [DeMiguel’18], energy generation and saving [Polman’12, Miller’17], spectrometry [Velasco’13a], sensing [Rodríguez-Barrios’10], medicine [Morgner’00] and industrial manufacturing [Malinauskas’16], to name a few. Particularly, integrated optics has attracted increasing industrial attention and scientific efforts to implement photonic integrated circuits (PICs) capable of tackling all abovementioned tasks in compact and efficient systems.Among all the available materials, silicon photonics leverages the maturity of the fabrication techniques reached by the microelectronics industry, enabling cost-effective mass production [Chen’18]. Different material platforms with a high refractive index contrast have been proposed for silicon photonics to achieve higher integration levels and perform more complex functions in a single chip, such as silicon-on-insulator (SOI) and silicon nitride (Si3N4, commonly simplified to SiN). The increased integration capacity of silicon photonics has enabled to tackle one of our greatest technological challenges: global data traffic inside data centers. Besides short-range optical interconnects for telecom and datacom applications, the progress in silicon photonics also encompasses many other untapped applications that are being explored by academia and industry: absorption spectroscopy and bio-sensing [Herrero-Bermello’17, Wangüemert-Pérez’19], light detection and ranging (LIDAR) [Poulton’17a], quantum computing [Harris’16], microwave and terahertz photonics [Marpaung’19, Harter’18], nonlinear optics [Leuthold’10], and many others...La fotónica ha adquirido una importancia fundamental en muchos ámbitos de nuestra vida cotidiana debido a su potencial intrínseco para desarrollar soluciones no sólo en el campo de las telecomunicaciones y las interconexiones de corto alcance, sino también en otras muchas áreas como la metrología [DeMiguel’18], la generación de energía [Polman’12, Miller’17], la espectrometría [Velasco’13a], la detección [Rodríguez-Barrios’10], la medicina [Morgner’00] y la fabricación industrial [Malinauskas’16]. En particular, la óptica integrada ha atraído tanto la atención de la industria como los esfuerzos científicos para implementar circuitos fotónicos integrados (PICs, Photonic Integrated Circuits) capaces de abordar todas las tareas mencionadas anteriormente en sistemas compactos y eficientes. Entre todos los materiales disponibles, la fotónica de silicio aprovecha la madurez de las técnicas de fabricación alcanzadas por la industria de la microelectrónica, permitiendo una producción en masa rentable [Chen’18]. Para maximizar su densidad de integración y poder realizar funciones más complejas en un único chip, diferentes plataformas materiales con un alto contraste de índice de refracción se han propuesto, como por ejemplo las plataformas de silicio sobre aislante (SOI, Silicon-On-Insulator) y de nitruro de silicio (Si3N4, comúnmente simplificada a SiN, Silicon Nitride). Esta mayor densidad de integración ha permitido abordar uno de nuestros mayores desafíos tecnológicos hasta la fecha: el tráfico de datos global dentro de los centros de datos. Además de las interconexiones ópticas de corto alcance, el progreso de la fotónica de silicio también comprende muchas otras aplicaciones inexploradas que están siendo estudiadas en el ámbito académico e industrial como, por ejemplo, la espectroscopía de absorción y biodetección [Herrero-Bermello’17, Wangüemert-Pérez’19], LIDAR (Light Detection And Ranging) [Poulton’17a], computación cuántica [Harris’16], fotónica de microondas y terahercios [Marpaung’19, Harter’18], óptica no lineal [Leuthold’10], y muchas otras...Fac. de Ciencias FísicasTRUEunpu

Intranet/internet: control y administración para servicios educativos

La presente tesis presenta las bases para la integración de un servidor Web con una base de datos, mediante la implementación de un formulario interactivo enlazado con una base de datos y sus posteriores aplicaciones prácticas. Básicamente, el trabajo consiste en suministrar las bases en cuanto a software necesario y configuración del servidor Web para implementar la aplicación anteriormente mencionada. Además de mencionar el ahorro en costos por ser una aplicación sencilla, utilizando herramientas informáticas de fácil aplicación. Son varias las aplicaciones prácticas que pueden generarse del proyecto; una de ellas es la utilización para los registros de estudiantes, la cual ha sido implementada y puede ser accesada por Web, permitiendo realizar consultas de materias, de estudiantes registrados, etc, información necesaria para la administración de las distintas unidades académicas

A theoretical study of the air-sea drag-saturation in very strong winds

The goal of this note is to provide a theoretical explanation for the saturation of the drag coefficient in strong wind conditions. The hydrodynamic model under consideration takes into account the important effects of airborne droplets of water in a thin layer above the water surface that effectively behave as a different fluid between the water and the air. Above this layer the model is coupled with a log-wind profile for the strong winds blowing above the sea. The main underlying mechanism governing the behavior of the drag coefficient is the Kelvin Helmholtz instability for capillary waves on the water surface and the continuity of shear stress along the intermediate interface

Mota-Engil : equity valuation

The main goal of this dissertation was to reach the price per share of Mota-Engil Group as of the 31st of December 2013. In order to achieve such goal, in a first stage, we performed a Literature Review – gathering and presenting the most commonly used methods of equity valuation. Moreover, we concluded that the Discounting Cash Flow model (more specifically the Free Cash Flow to the Firm approach) was the most appropriate to value the price of Mota-Engil’s shares. Plus, we also show the results achieved through Relative Valuation. Our target price is 9.65€ per share whereas the price practiced by the market at such date was 4.32€. Thus, according to the model by us developed, Mota-Engil’s shares were undervalued, in the end of 2013

Lobby Watch: The Social Issues Research Centre

First paragraph: The Social Issues Research Centre (SIRC) is an "independent, non-profit organisation" that says it carries out "balanced, calm and thoughtful" research on lifestyle issues such as drinking, diet, and pharmaceuticals (www.sirc.org). However, it may be perceived that the organisation acts more like a public relations agency for the corporations that fund its activities. These include Diageo, Flora, Coca-Cola, GlaxoSmithKline, and Roche, among others. Although SIRC does publish this partial list of funders, it is not immediately apparent which company has sponsored which study. And in some instances this information is not included in media reports