Long range forces induced by neutrinos at finite temperature

We revisit and extend previous work on neutrino mediated long range forces in a backround at finite temperature. For Dirac neutrinos, we correct existing results. We also give new results concerning spin-dependent as well as spin-independent long range forces associated to Majorana neutrinos. An interesting outcome of the investigation is that, for both types of neutrinos whether massless or not, the effect of the relic neutrino heat bath is to convert those forces into attractive ones in the supra-millimeter scale while they stay repulsive within the sub-millimeter scale.Comment: 8 pages, Latex, 1 figur

Tendency of spherically imploding plasma liners formed by merging plasma jets to evolve toward spherical symmetry

Three dimensional hydrodynamic simulations have been performed using smoothed particle hydrodynamics (SPH) in order to study the effects of discrete jets on the processes of plasma liner formation, implosion on vacuum, and expansion. The pressure history of the inner portion of the liner was qualitatively and quantitatively similar from peak compression through the complete stagnation of the liner among simulation results from two one dimensional radiationhydrodynamic codes, 3D SPH with a uniform liner, and 3D SPH with 30 discrete plasma jets. Two dimensional slices of the pressure show that the discrete jet SPH case evolves towards a profile that is almost indistinguishable from the SPH case with a uniform liner, showing that non-uniformities due to discrete jets are smeared out by late stages of the implosion. Liner formation and implosion on vacuum was also shown to be robust to Rayleigh-Taylor instability growth. Interparticle mixing for a liner imploding on vacuum was investigated. The mixing rate was very small until after peak compression for the 30 jet simulation.Comment: 28 pages, 16 figures, submitted to Physics of Plasmas (2012

Liquid sloshing in elastic containers

Coupled oscillations of elastic container partially filled with incompressible liqui

Evaluating a continuing professional development course on cognitive functions for Music Therapists working in care homes

Scarce research to date has addressed the aspect of Continuing Professional Development (CPD) as a key requirement for qualified music therapists. The present study investigated the benefits of a CPD course based on cognitive neuropsychology, which aimed to develop music therapists’ knowledge and skills in care home settings. The course included 32h of activities spread across 3 months and was attended by 31 music therapists. This course was evaluated using a mixed-methods approach including a semi-structured interview and a quantitative questionnaire. The results revealed that the CPD course brought different benefits meeting the needs of the therapists working in the care homes, which, included: i) improved general knowledge of music cognition, ii) broadened thinking about music therapy practice and clients’ abilities, and iii) an additional clinical and theoretical framework. These results are consistent with previous literature, highlighting the importance of providing advanced training for music therapists. Crucially, the findings highlighted the need for different strategies, techniques and pedagogical approaches in CPD courses, in function of the work setting, to improve attendees’ clinical skills. In addition, the study outlines how a CPD course may be tailored to enhance specific skills and transfer of learning in line with workplace demands

The Determinants of Price in Online Auctions: More Evidence from Quantile Regression

This study explores how seller reputations affect auction prices, and concludes that earlier findings may be biased due to the misspecification of seller reputation. This paper contributes to the literature by offering significant empirical evidence using Taiwanese Internet auction data. Our study reveals that the influence of seller reputations on auction prices is significant, irrespective of the assumptions of linear and non-linear relationships with price. However, failure to consider the non-linear setting of seller reputation would have led us to overestimate the impact of reputations on prices because marginal returns to an incremental increase in reputation declines rapidly for sellers who have more than 15 scores. In addition, using quantile regression, this study finds evidence of considerable differences in their impact on auction prices dependent on the distribution of price levels

STEPS - an approach for human mobility modeling

In this paper we introduce Spatio-TEmporal Parametric Stepping (STEPS) - a simple parametric mobility model which can cover a large spectrum of human mobility patterns. STEPS makes abstraction of spatio-temporal preferences in human mobility by using a power law to rule the nodes movement. Nodes in STEPS have preferential attachment to favorite locations where they spend most of their time. Via simulations, we show that STEPS is able, not only to express the peer to peer properties such as inter-ontact/contact time and to reflect accurately realistic routing performance, but also to express the structural properties of the underlying interaction graph such as small-world phenomenon. Moreover, STEPS is easy to implement, exible to configure and also theoretically tractable

Evidence for Anisotropic Vortex Dynamics and Pauli Limitation in the Upper Critical Field of FeSe1-xTex

We have determined HC2(T) for FeSe1-xTex (x=0.52) single crystals using resistivity measurements at high static and pulsed magnetic field, as well as specific heat measurements up to 9T. We find that the significant anisotropy of the initial slope of HC2(T) determined from resistivity measurements, is not present when HC2 is determined from the specific heat results. This suggests that the thermodynamic upper critical field is almost isotropic, and that anisotropic vortex dynamics play a role. Further evidence of anisotropic vortex dynamics is found in the behaviour in pulsed field. We also find that Pauli limiting must be included in order to fit the temperature dependence of HC2, indicating probably higher effective mass in FeSe1-xTex than in other Fe superconductors