A critical evaluation of training needs for child protection in UK sport

Child protection is a relatively new topic in sport about which there was no professional education until the mid-1990s. This paper presents the findings from a study of delegates attending twelve, regional, one-day National Coaching Foundation courses for policy makers in sport during 1997 and 1998 (n= 235). The course was designed to give delegates a basic awareness of the different forms of child abuse and protection and was intended to help them develop appropriate policies and procedures for child protection. Results point to a serious training gap around child protection in sport: whereas sports personnel, at both junior and senior levels, are committed to improving child protection policy and practice they appear to lack the confidence, knowledge or organisational systems for doing this effectively

Coherent states of a charged particle in a uniform magnetic field

The coherent states are constructed for a charged particle in a uniform magnetic field based on coherent states for the circular motion which have recently been introduced by the authors.Comment: 2 eps figure

Clustering of ions at atomic dimensions in quantum plasmas

By means of particle simulations of the equations of motion for ions interacting among themselves under the influence of newly discovered Shukla–Eliasson attractive force (SEAF) in a dense quantum plasma, we demonstrate that the SEAF can bring ions closer at atomic dimensions. We present simulation results of the dynamics of an ensemble of ions in the presence of the SEAF without and with confining external potentials and collisions between ions and degenerate electrons. Our particle simulations reveal that under the SEAF, ions attract each other, come closer, and form ionic clusters in the bath of degenerate electrons that shield ions. Furthermore, an external confining potential produces robust ion clusters that can have cigar- and ball-like shapes, which remain stable when the confining potential is removed. The stability of ion clusters is discussed. Our results may have applications to solid density plasmas (density exceeding 1023 per cm3), where the electrons will be degenerate and quantum forces due to the electron recoil effect caused by the overlapping of electron wave functions and electron tunneling through the Bohm potential, electron-exchange and electron-exchange and electron correlations associated with electron-1/2 spin effect, and the quantum statistical pressure of the degenerate electrons play a decisive role

Simulations of magnetic and magnetoelastic properties of Tb2Ti2O7 in paramagnetic phase

Magnetic and magnetoelastic properties of terbium titanate pyrochlore in paramagnetic phase are simulated. The magnetic field and temperature dependences of magnetization and forced magnetostriction in Tb2Ti2O7 single crystals and polycrystalline samples are calculated in the framework of exchange charge model of crystal field theory and a mean field approximation. The set of electron-deformation coupling constants has been determined. Variations of elastic constants with temperature and applied magnetic field are discussed. Additional strong softening of the crystal lattice at liquid helium temperatures in the magnetic field directed along the rhombic symmetry axis is predicted.Comment: 13 pages, 4 figures, 2 table

Equivariant differential characters and symplectic reduction

We describe equivariant differential characters (classifying equivariant circle bundles with connections), their prequantization, and reduction

Excitation of multiple wakefields by short laser pulses in dense plasmas

We present a theoretical investigation of the excitation of multiple electrostatic wakefields by the ponderomotive force of a short electromagnetic pulse propagating through a dense plasma. It is found that the inclusion of the quantum statistical pressure and quantum electron tunneling effects can qualitatively change the classical behavior of the wakefield. In addition to the well known plasma oscillation wakefield, with a wavelength of the order of the electron skin depth, which in a dense plasma is of the order of several nanometers, wakefields in dense plasmas with a shorter wavelength are also excited. The wakefields can trap electrons and accelerate them to extremely high energies over nanoscales.Comment: 4 pages, 3 figure

Employing combination procedures to short-time EOP prediction

A well known problem with Earth Orientation Parameters (EOP) prediction is that a prediction strategy proved to be the best for some testing time span and prediction length may not remain the same for other time intervals. In this paper, we consider possible strategies to combine EOP predictions computed using different analysis techniques to obtain a final prediction with the best accuracy corresponding to the smallest prediction error of input predictions. It was found that this approach is most efficient for ultra-short-term EOP forecast.Comment: 7 pages, presented at the IERS Workshop on EOP Combination and Prediction, Warsaw, Poland, 19-21 Oct 200

One-Parameter Squeezed Gaussian States of Time-Dependent Harmonic Oscillator and Selection Rule for Vacuum States

By using the invariant method we find one-parameter squeezed Gaussian states for both time-independent and time-dependent oscillators. The squeezing parameter is expressed in terms of energy expectation value for time-independent case and represents the degree of mixing positive and negative frequency solutions for time-dependent case. A {\it minimum uncertainty proposal} is advanced to select uniquely vacuum states at each moment of time. We show that the Gaussian states with minimum uncertainty coincide with the true vacuum state for time-independent oscillator and the Bunch-Davies vacuum for a massive scalar field in a de Sitter spacetime.Comment: 13 Pages, ReVTeX, no figure

Nonequilibrium orientational patterns in two-component Langmuir monolayers

A model of a phase-separating two-component Langmuir monolayer in the presence of a photo-induced reaction interconvering two components is formulated. An interplay between phase separation, orientational ordering and treaction is found to lead to a variety of nonequilibrium self-organized patterns, both stationary and traveling. Examples of the patterns, observed in numerical simulations, include flowing droplets, traveling stripes, wave sources and vortex defects.Comment: Submitted to the Physical Review

Time-Dependent Invariants for Dirac Equation and Newton-Wigner Position Operator

For Dirac equation, operator-invariants containing explicit time-dependence in parallel to known time-dependent invariants of nonrelativistic Schr\"odinger equation are introduced and discussed. As an example, a free Dirac particle is considered and new invariants are constructed for it. The integral of motion, which is initial Newton-Wigner position operator, is obtained explicitly for a free Dirac particle. For such particle with kick modeled by delta-function of time, the time-depending integral, which has physical meaning of initial momentum, is found.Comment: LATEX,21 pages,submitted to Physica Script