Gravitational waves in massive gravity theories: waveforms, fluxes and constraints from extreme-mass-ratio mergers

Is the graviton massless? This problem was addressed in the literature at a phenomenological level, using modified dispersion relations for gravitational waves, in linearized calculations around flat space. Here, we perform a detailed analysis of the gravitational waveform produced when a small particle plunges or inspirals into a large non-spinning black hole. Our results should presumably also describe the gravitational collapse to black holes and explosive events such as supernovae. In the context of a theory with massive gravitons and screening, merging objects up to $1\,{\rm Gpc}$ away or collapsing stars in the nearby galaxy may be used to constrain the mass of the graviton to be smaller than $\sim 10^{-23}\,{\rm eV}$, with low-frequency detectors. Our results suggest that the absence of dipolar gravitational waves from black hole binaries may be used to rule out entirely such theories.Comment: Important clarifications on screening and on our results added. Accepted for publication in Physical Review Letter

A sua Interligação com os Módulos EAPS, FI e MM

A evolução das Tecnologias de Informação na recolha de dados, no processamento e distribuição da informação, associada a mudanças no seu meio envolvente, tem motivado as organizações a tornarem-se muito diferentes na sua estrutura e na forma da organização do trabalho. Em Portugal, dois normativos legais consubstanciam esta necessidade de adaptação; a Resolução do Conselho de Ministros nº 109/2005, de 2 de Junho e a Resolução do Conselho de Ministros nº 124/2005, de 8 de Julho. O primeiro elegeu a modernização da Administração Pública como componente essencial da estratégia de desenvolvimento do país e o segundo estabeleceu os princípios para a reestruturação da Administração Central do Estado, dando ênfase à simplificação, racionalização e reengenharia de procedimentos administrativos. Recorrendo ao estudo de dois casos de implementação do módulo de Project System na Direcção de Abastecimento e Transportes da Força Aérea Portuguesa e na Direcção de Abastecimento da Marinha, tentaremos obter um conhecimento sustentado sobre a influência do módulo na racionalização de meios humanos e na simplificação de processos administrativos, identificando eventuais oportunidades e condicionamentos. Demonstraremos que o módulo de Project System, devidamente implementado, contribui para a racionalização de meios humanos e para a simplificação de processos administrativos nas Unidades da Força Aérea Portuguesa com Grupo de Apoio Constituído. Com o decorrer da investigação também nos apercebemos do contributo que o módulo de Project System fornece para um melhor controlo interno sobre as Unidades da Força Aérea. Este estudo foi desenvolvido com base no método de investigação em Ciências Sociais proposto por Raymond Quivy e Luc Van Campenhoudt (1998). Abstract: The evolution of Information Technologies in the collection of data, its processing and the partaking of its contents, associated to changes on the surrounding context, has motivated organisations to change, becoming different in terms of configuration and labour organisation. In Portugal, two legal regulations have embodied this need to change and adapt: The Ministrie’s Council Resolution No. 109/2005, of the 2nd of June and the Ministrie’s Council Resolution No. 124/2005, of 4th of August. The first one elected the modernisation of Public Administration as an essential component in the country’s development strategy and the second established the principles necessary to the due reform of the State’s Central Administration, underlining issues related to the simplification, rationalization and re-engineering of administrative procedures. Using the study of two cases of implementation of the Module PS, namely in the DAT service of Portuguese Air Force and in the DA service of the Navy, we will try to obtain sustained information on the influence of this module in the rationalization of human resources and in the simplification of administrative procedures, identifying in the process eventual opportunities and limitations. We will show that the PS Module, if duly implemented, will contribute to the rationalization of means and human resources and to the simplification of administrative procedures in those units of the Air Forces with an established support group. As we went along the investigation, we could also perceive the relevant contribution the PS Module can provide for a better internal control over the Air Force Units. This study has been conducted with basis on the investigation methodology proposed by Raymond Quivy and Luc Van Campenhoudt (1998)

A Robust Role for Motor Cortex

The function of mammalian motor cortex has remained a persistent mystery. There is a long history of research linking activity in this part of the brain with the control of voluntary movements but surprisingly there is an equally large body of evidence in non-human animals describing all kinds of complex behaviours that are not impaired when motor cortex is fully removed. What is the reason behind this discrepancy? What kind of movements are actually controlled by motor cortex? This thesis attempts to reconcile the many con icting views on the cortical control of movement and outline a strategy for investigating the teleology of this brain region. We start out by introducing a new set of hardware and software tools for neuroscience that aim to make it easier to study in detail more naturalistic motor behaviours in rodents. These tools allow the experimenter to quickly recon gure the physical and virtual environment of a behaviour task while simultaneously tracking in real-time ne-scale measurements of motor performance. (...)Sainsbury Wellcome Centre for Neural Circuits and Behaviour at University College LondonChampalimaud Foundatio

Hamster: um rato simples

Este artigo descreve o agente robótico Hamster participante no concurso Ciber-Rato 2002 integrado no Festival Nacional de Robótica 2002. Este robô utiliza um algoritmo que, apesar da sua simplicidade apresenta uma eficiência razoável

Ic paper on elekta ab - mitigation of structural differences in cancer treatment

The following Investment Committee paper focuses on a proposal for a leveraged buyout on Elekta AB, a key player in the global radiotherapy market which sells in more than 120 countries. In fact, this paper develops a set of value creation strategies (with an emphasis on the Buy & Build strategy) through a detailed analysis of the radiotherapy market and of the competitive advantages of the company. Subsequently, a capital structure is suggested by assessing past buyout transactions in the healthcare sector and by leveraging the bank case. Finally, the exit returns are estimated complying with industry threshold and a range of exit strategies are analyzed

Evolution of female carotenoid coloration by sexual constraint in Carduelis finches

<p>Abstract</p> <p>Background</p> <p>Females often express the same ornaments as males to a similar or lesser degree. Female ornaments can be adaptive, but little is known regarding their origins and mode of evolution. Current utility does not imply evolutionary causation, and therefore it is possible that female ornamentation evolved due to selection on females, as a correlated response to selection on males (sexual constraint), or a combination of both. We tested these ideas simulating simple models for the evolution of male and female correlated traits, and compared their predictions against the coloration of finches in the genus <it>Carduelis</it>.</p> <p>Results</p> <p>For carotenoid-based ornamental coloration, a model of sexual constraint on females fits the <it>Carduelis </it>data well. The two alternative models (sexual constraint on males, and mutual constraint) were rejected as causing the similarities in carotenoid coloration between males and females. For melanin coloration, the correlation between the sexes was weaker, indicating that males and females evolved independently to a greater extent.</p> <p>Conclusions</p> <p>This indicates that sexual constraint on females was an important mechanism for the evolution of ornamental carotenoid coloration in females, but less so for melanin coloration. This does not mean that female carotenoid coloration is non-adaptive or maladaptive, because sexual dichromatism could evolve if it were maladaptive. It suggests, however, that most evolution of female carotenoid coloration was male-driven and, when adaptive, may not be an adaptation <it>stricto sensu</it>.</p

Photoallergic contact dermatitis from benzydamine presenting mainly as lip dermatitis

BACKGROUND: Benzydamine, a non-steroidal anti-inflammatory drug (NSAID) in use for more than four decades, has been reported to cause photosensitivity. OBJECTIVES: To study the results of photopatch testing to benzydamine and the clinical features of the dermatitis during a 3-year period (2006-2008). PATIENTS AND METHODS: During this period, 74 patients with photodermatoses were photopatch tested with an extended baseline series of allergens including benzydamine and in suspicious cases, with drugs that contain it. Test sites were irradiated on D2 with 5 J/cm(2) and readings were performed on D2 and D4. RESULTS: Ten patients (six females/four males), aged 21-84 years (mean 64.9) had a positive photopatch test to benzydamine [1-5% petrolatum (pet.) from Bial-Aristegui] and to drugs that contain it (Tantum verde oral solution and Momen gel). Nine patients had lower lip cheilitis and one lichenified eczema on photo-exposed sites. CONCLUSION: Photosensitivity from both topical and systemic benzydamine has been occasionally described, mainly in southern Spain. Despite its widespread use and its known photosensitizing capacity, photoallergic contact dermatitis from benzydamine is probably underdiagnosed as the clinical presentation of mainly the lip and chin is not typical of photoallergic contact dermatitis and benzydamine is not part of most photoallergen series