Point-source scalar turbulence

The statistics of a passive scalar randomly emitted from a point source is investigated analytically. Our attention has been focused on the two-point equal-time scalar correlation function. The latter is indeed easily related to the spectrum, a statistical indicator widely used both in experiments and in numerical simulations. The only source of inhomogeneity/anisotropy is in the injection mechanism, the advecting velocity here being statistically homogeneous and isotropic. Our main results can be summarized as follows. 1) For a very large velocity integral scale, a pure scaling behaviour in the distance between the two points emerges only if their separation is much smaller than their distance from the point source. 2) The value we have found for the scaling exponent suggests the existence of a direct cascade, in spite of the fact that here the forcing integral scale is formally set to zero. 3) The combined effect of a finite inertial-range extension and of inhomogeneities causes the emergence of subleading anisotropic corrections to the leading isotropic term, that we have quantified and discussed.Comment: 10 pages, 1 figure, submitted to Journal of Fluid Mechanic

Fit for public consumption: An exploratory study of the reporting of nutrition research in UK tabloids and public attitudes towards it

Newspapers constitute a popular form of mass media within the UK; presenting a valuable opportunity for disseminating key nutrition and health messages. This qualitative, exploratory study examined tabloid articles reporting on nutrition research, and public attitudes towards them. All popular tabloids were included and articles were sampled over a full calendar month. A tool was designed to test for accuracy with respect to the original research, balance, and presence of appropriate contextualised information. Thirty-nine features were systematically assessed using the tool. Two focus groups were conducted to explore public attitudes towards specific tabloid articles. Questions were centred on the cognitive, affective and behavioural elements of attitude formation. The groups were audio recorded, transcribed, and emerging themes were established. Findings indicated that tabloid articles were essentially inaccurate, biased, and not effectively contextualised. Attitudes expressed within the focus groups were largely negative and suggested that tabloid articles could confuse members of the public. Articles were more likely to be disregarded than acted upon, however there was some value attached to newspapers providing nutrition information, inferring that opportunities to effectively use this media are not completely lost

More Than Brides Alliance: Baseline report, India

The More Than Brides Alliance seeks to improve the lives of adolescent girls and includes activities across multiple domains (reproductive health, education, gender norms, and livelihoods, to name a few). The Population Council conducted surveys of adolescent girls and young women aged 12–19 in nine districts in four states in India to examine girls’ experiences, including education, marriage and relationships, literacy and numeracy, livelihoods, and gender-equitable attitudes. The study found that few girls were currently involved in any programs, despite demonstrated vulnerabilities (e.g., more than half of the sample was currently out of school) suggesting that there is a clear need for interventions to address vulnerabilities in this population. Findings from the baseline study will be used to evaluate changes over time that may be attributable to the MTBA intervention and to inform programmatic staff seeking to understand the populations they are serving

Random walks and search in time-varying networks

The random walk process underlies the description of a large number of real world phenomena. Here we provide the study of random walk processes in time varying networks in the regime of time-scale mixing; i.e. when the network connectivity pattern and the random walk process dynamics are unfolding on the same time scale. We consider a model for time varying networks created from the activity potential of the nodes, and derive solutions of the asymptotic behavior of random walks and the mean first passage time in undirected and directed networks. Our findings show striking differences with respect to the well known results obtained in quenched and annealed networks, emphasizing the effects of dynamical connectivity patterns in the definition of proper strategies for search, retrieval and diffusion processes in time-varying network

Wireless sensor network for helicopter rotor blade vibration monitoring: Requirements definition and technological aspects

The main rotor accounts for the largest vibration source for a helicopter fuselage and its components. However, accurate blade monitoring has been limited due to the practical restrictions on instrumenting rotating blades. The use of Wireless Sensor Networks (WSNs) for real time vibration monitoring promises to deliver a significant contribution to rotor performance monitoring and blade damage identification. This paper discusses the main technological challenges for wireless sensor networks for vibration monitoring on helicopter rotor blades. The first part introduces the context of vibration monitoring on helicopters. Secondly, an overview of the main failure modes for rotor and blades is presented. Based on the requirements for failure modes monitoring, a proposition for a multipurpose sensor network is presented. The network aims to monitor rotor performance, blade integrity and damage accumulation at three different scales referred to as macro layer, meso layer and micro layer. The final part presents the requirements for WSNs design in relation with sensing, processing, communication, actuation and power supply.\u

Asteroseismology of the Hyades with K2: first detection of main-sequence solar-like oscillations in an open cluster

The Hyades open cluster was targeted during Campaign 4 (C4) of the NASA K2 mission, and short-cadence data were collected on a number of cool main-sequence stars. Here, we report results on two F-type stars that show detectable oscillations of a quality that allows asteroseismic analyses to be performed. These are the first ever detections of solar-like oscillations in main-sequence stars in an open cluster.Comment: 12 pages, 8 figures, 2 tables; accepted for publication in MNRA

Morally Respectful Listening and its Epistemic Consequences

What does it mean to listen to someone respectfully, that is, insofar as they are due recognition respect? This paper addresses that question and gives the following answer: it is to listen in such a way that you are open to being surprised. A specific interpretation of this openness to surprise is then defended

Probing the properties of convective cores through g modes: high-order g modes in SPB and gamma Doradus stars

In main sequence stars the periods of high-order gravity modes are sensitive probes of stellar cores and, in particular, of the chemical composition gradient that develops near the outer edge of the convective core. We present an analytical approximation of high-order g modes that takes into account the effect of the mu gradient near the core. We show that in main-sequence models, similarly to the case of white dwarfs, the periods of high-order gravity modes are accurately described by a uniform period spacing superposed to an oscillatory component. The periodicity and amplitude of such component are related, respectively, to the location and sharpness of the mu gradient. We investigate the properties of high-order gravity modes for stellar models in a mass domain between 1 and 10 Msun, and the effects of the stellar mass, evolutionary state, and extra-mixing processes on period spacing features. In particular, we show that for models of a typical SPB star, a chemical mixing that could likely be induced by the slow rotation observed in these stars, is able to significantly change the g-mode spectra of the equilibrium model. Prospects and challenges for the asteroseismology of gamma Doradus and SPB stars are also discussed.Comment: 18 pages, 29 figures, accepted for publication in MNRA