ρ\rho Polarization and `Model Independent' Extraction of ∣Vub∣/∣Vcd∣|V_{ub}|/|V_{cd}| from D→ρℓνD\to\rho\ell\nu and B→ρℓνB\to\rho\ell\nu

We briefly discuss the predictions of the heavy quark effective theory for the semileptonic decays of a heavy pseudoscalar to a light one, or to a light vector meson. We point out that measurement of combinations of differential helicity decay rates at Cleo-c and the $B$ factories can provide a model independent means of extracting the ratio $|V_{ub}|/|V_{cd}|$. We briefly discuss the corrections to this prediction.Comment: 8 pages, LaTeX, 1 figur

Not all players are equally motivated: The role of narcissism.

Abstract Research on motivational climates consistently demonstrates that mastery-focused climates are associated with positive outcomes and ego-involving performance climates lead to maladaptive outcomes. However, the role of personality within such a framework has been largely ignored. To redress this imbalance, we examined the potential role of narcissism in moderating the effects of different motivational climates on leader-inspired extra effort in training. Training is where rugby players spend most of their rugby time and we were keen to examine the combination of personality and climate that might maximise the yield of such training environments. Female rugby players (n = 126) from 15 clubs completed measures of narcissism, motivational climate and effort. Moderated regression analyses revealed that narcissism moderated the relationship between motivational climate and effort. Increases in either performance or mastery climates were associated with increases in effort for narcissists; no such relationship was revealed for low narcissists. The findings demonstrate the importance of considering personality within rugby training environments, as it is clear that not every player will respond the same way to specific training conditions. Coaches who understand this and are able to tailor individualised motivational climates will likely gain the greatest benefits from their different players

On non-QRT Mappings of the Plane

We construct 9-parameter and 13-parameter dynamical systems of the plane which map bi-quadratic curves to other bi-quadratic curves and return to the original curve after two iterations. These generalize the QRT maps which map each such curve to itself. The new families of maps include those that were found as reductions of integrable lattices

Fault fictions : systematic biases in the conceptualization of fault zones

Mental models (i.e. a human’s internal representation of the real world) have an important role in the way a human understands and reasons about uncertainties, explores potential options, and makes decisions. However, they are susceptible to biases. Issues associated with mental models have not yet received much attention in geosciences, yet systematic biases can affect the scientific process of any geological investigation; from the inception of how the problem is viewed, through selection of appropriate hypotheses and data collection/processing methods, to the conceptualisation and communication of results. This article draws on findings from cognitive science and system dynamics, with knowledge and experiences of field geology, to consider the limitations and biases presented by mental models in geoscience, and their effect on predictions of the physical properties of faults in particular. We identify a number of biases specific to geological investigations and propose strategies for debiasing. Doing so will enhance how multiple data sources can be brought together, and minimise controllable geological uncertainty to develop more robust geological models. Critically, we argue that there is a need for standardised procedures that guard against biases, permitting data from multiple studies to be combined and communication of assumptions to be made. While we use faults to illustrate potential biases in mental models and the implications of these biases, our findings can be applied across the geoscience discipline

Magneto-Acoustic Wave Oscillations in Solar Spicules

Some observations suggest that solar spicules show small amplitude and high frequency oscillations of magneto-acoustic waves, which arise from photospheric granular forcing. We apply the method of MHD seismology to determine the period of kink waves. For this purposes, the oscillations of a magnetic cylinder embedded in a field-free environment is investigated. Finally, diagnostic diagrams displaying the oscillatory period in terms of some equilibrium parameters are provided to allow a comparison between theoretical results and those coming from observations.Comment: 10 pages, 4 fig

Looking into the matter of light-quark hadrons

In tackling QCD, a constructive feedback between theory and extant and forthcoming experiments is necessary in order to place constraints on the infrared behaviour of QCD's \beta-function, a key nonperturbative quantity in hadron physics. The Dyson-Schwinger equations provide a tool with which to work toward this goal. They connect confinement with dynamical chiral symmetry breaking, both with the observable properties of hadrons, and hence provide a means of elucidating the material content of real-world QCD. This contribution illustrates these points via comments on: in-hadron condensates; dressed-quark anomalous chromo- and electro-magnetic moments; the spectra of mesons and baryons, and the critical role played by hadron-hadron interactions in producing these spectra.Comment: 11 pages, 7 figures. Contribution to the Proceedings of "Applications of light-cone coordinates to highly relativistic systems - LIGHTCONE 2011," 23-27 May, 2011, Dallas. The Proceedings will be published in Few Body System

A large scale investigation into changes in coal quality caused by dolerite dykes in Secunda, South Africa-implications for the use of proximate analysis on a working mine

The coalfields of South Africa contain numerous dolerite intrusions, which affected the quality of the surrounding coal through thermal processes, commonly believed to be controlled by the size of the magmatic body. Data gathered from a working coalfield in Secunda, South Africa, suggest that the relationship between intrusive sills and coal is complex and factors other than intrusion width must be considered in relation to the contact metamorphic effect. The study area contains multiple dolerite intrusions of Karoo age, of which three intrusions occur as sills intruded close to the main coal seam of the. A large database (>8000 boreholes) of coal quality data was used to investigate the presence or absence of a change in coal quality relative to dolerite proximity. Reduction in coal quality was defined using three proximate analysis values, namely the ash, volatile content and dry ash free volatile (DAFV) as defined in the coal industry. The resultant investigation showed no correlation between the position and thickness of the dolerites, and changes in coal quality as measured by proximate analysis. In the absence of a linear relationship between coal quality and dolerite proximity, two processes are proposed to explain the absence of the contact metamorphic effects expected from previous studies. Firstly dolerite emplacement dynamics may influence the size of the metamorphic aureole produced by an intrusion, invalidating intrusion size as a measure of thermal output. Secondly, hydrothermal fluids mobilised by the dolerite intrusions, either from the country rock or the intrusion itself may percolate through the coal and act as the metamorphic agent responsible for changing coal quality, by dissolving the volatile and semi-volatile components of the coal and transporting them to other locations. These two processes are sufficient to explain the lack of a clear “metamorphic effect” related to the dolerite intrusions. However, the perceived lack of a clear correlation between the coal quality parameters and the metamorphic effects associated with dolerite intrusion may also reflect the inadequacies of proximate analysis techniques in quantifying geological processes within the coal.Coaltech research organisation.http://www.elsevier.com/locate/jafrearsci2017-05-31hb2016Geolog

Do environmental concerns affect commuting choices? Hybrid choice modelling with household survey data

In order to meet their ambitious climate change goals governments around the world will need to encourage behaviour change as well as technological progress; and in particular they need to weaken our attachment to the private car. A prerequisite to designing effective policy is a thorough understanding of the factors that drive behaviours and decisions. In an effort to better understand how the public’s environmental attitudes affect their behaviours we estimate a hybrid choice model (HCM) for commuting mode choice using a large household survey data set. HCMs combine traditional discrete choice models with a structural equation model to integrate latent variables, such as attitudes and other psychological constructs, into the choice process. To date HCMs have been estimated on small bespoke data sets, beset with problems of sample selection, focusing effects and limited generalizability. To overcome these problems we demonstrate the feasibility of using this valuable modelling approach with nationally representative data. Our estimates suggest that environmental attitudes and behaviours are separable constructs, and both have an important influence on commute mode choice. These psychological factors can be exploited by governments looking to add to their climate change policy toolbox in an effort to change travel behaviours