26,456 research outputs found

    Normative values for the profile of mood states for use with athletic samples

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    The Profile of Mood States (POMS) has been used extensively for the assessment of mood in the sport and exercise environments. The purpose of the study was to develop tables of normative values based on athletic samples. Participants (N = 2,086), comprising athletes at the international (n = 622), club (n = 628), and recreational (n = 836) levels, completed the POMS in one of three situations: pre-competition/exercise, post-competition/exercise, and away from the athletic environment. Differences between the athletic sample and existing norms were found for all mood subscales. Main effects of level of competition and situation were identified. The results support the proposition that the use of the original tables of normative values in sport and exercise environments is inappropriate

    Re-evaluation of the factorial validity of the Revised Competitive State Anxiety Inventory-2

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    Anxiety is one of the most frequently researched constructs in the field of sport and exercise psychology. Although there are at least 22 published scales available to measure anxiety (see Ostrow, 1996), the Competitive State Anxiety Inventory-2 (CSAI-2: Martens, Burton, Vealey, Bump, & Smith, 1990) has generally been the scale of choice since its development. Given its prominence as a research tool, indeed it was described by Woodman and Hardy (2003, p.453) as having 'near sine qua non status', the CSAI-2 has naturally been the subject of considerable scrutiny of its psychometric characteristics. Several studies have now been published which have raised concerns about the factorial validity of the CSAI-2 in its English (Cox, Martens, & Russell, 2003; Lane, Sewell, Terry, Bartram, & Nesti, 1999), Greek (Tsorbatzoudis, Varkoukis, Kaissidis-Rodafinos, & Grouios, 1998), and Swedish (Lundqvist & Hassmen, in press) versions. Collectively, reevaluations of its psychometric properties have raised serious doubts about the validity of the CSAI-2 in its original form and by implication have cast a shadow over the findings of dozens of studies that have used it to measure anxiety. To address this situation, Cox et al. (2003) conducted a two-stage process using calibration and validation samples to arrive at an improved measure. Having deleted problematic items in the original CSAI-2 and having subsequently supported the factorial validity of a revised version of the measure, termed the CSAI-2R, they recommended that researchers and clinicians should in future use the revised measure in preference to the original. The purpose of the present study was to re-evaluate the factorial validity of the CSAI-2R, as recommended by Cox and colleagues. Considering the potential for the revised measure to become the new scale of choice for researchers in the sport and exercise domains, this is judged to be an important contribution to the anxiety literature

    Charge assignments in multiple-U(1) gauge theories

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    We discuss the choice of gauge field basis in multiple-U(1) gauge theories. We find that there is a preferred basis, specified by the charge orthogonality condition, in which the U(1) gauge fields do not mix under one-loop renormalization group running.Comment: 7 pages, LaTe

    List of the Elateridae of British Columbia

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    Geometry of PT-symmetric quantum mechanics

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    Recently, much research has been carried out on Hamiltonians that are not Hermitian but are symmetric under space-time reflection, that is, Hamiltonians that exhibit PT symmetry. Investigations of the Sturm-Liouville eigenvalue problem associated with such Hamiltonians have shown that in many cases the entire energy spectrum is real and positive and that the eigenfunctions form an orthogonal and complete basis. Furthermore, the quantum theories determined by such Hamiltonians have been shown to be consistent in the sense that the probabilities are positive and the dynamical trajectories are unitary. However, the geometrical structures that underlie quantum theories formulated in terms of such Hamiltonians have hitherto not been fully understood. This paper studies in detail the geometric properties of a Hilbert space endowed with a parity structure and analyses the characteristics of a PT-symmetric Hamiltonian and its eigenstates. A canonical relationship between a PT-symmetric operator and a Hermitian operator is established. It is shown that the quadratic form corresponding to the parity operator, in particular, gives rise to a natural partition of the Hilbert space into two halves corresponding to states having positive and negative PT norm. The indefiniteness of the norm can be circumvented by introducing a symmetry operator C that defines a positive definite inner product by means of a CPT conjugation operation.Comment: 22 Page

    Morphology-dependent trends of galaxy age with environment in Abell 901/902 seen with COMBO-17

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    We investigate correlations between galaxy age and environment in the Abell 901/2 supercluster for separate morphologies. Using COMBO-17 data, we define a sample of 530 galaxies, complete at MV5logh<18M_V -5\log h<-18 on an area of 3.5×3.53.5\times 3.5 (Mpc/hh)2^2. We explore several age indicators including an extinction-corrected residual from the colour-magnitude relation (CMR). As a result, we find a clear trend of age with density for galaxies of all morphologies that include a spheroidal component, in the sense that galaxies in denser environments are older. This trend is not seen among Scd/Irr galaxies since they all have young ages. However, the trend among the other types is stronger for fainter galaxies. While we also see an expected age-morphology relation, we find no evidence for a morphology-density relation at fixed age.Comment: Accepted for publication in MNRAS (Letters

    Ultracold, radiative charge transfer in hybrid Yb ion - Rb atom traps

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    Ultracold hybrid ion-atom traps offer the possibility of microscopic manipulation of quantum coherences in the gas using the ion as a probe. However, inelastic processes, particularly charge transfer can be a significant process of ion loss and has been measured experimentally for the Yb+^{+} ion immersed in a Rb vapour. We use first-principles quantum chemistry codes to obtain the potential energy curves and dipole moments for the lowest-lying energy states of this complex. Calculations for the radiative decay processes cross sections and rate coefficients are presented for the total decay processes. Comparing the semi-classical Langevin approximation with the quantum approach, we find it provides a very good estimate of the background at higher energies. The results demonstrate that radiative decay mechanisms are important over the energy and temperature region considered. In fact, the Langevin process of ion-atom collisions dominates cold ion-atom collisions. For spin dependent processes \cite{kohl13} the anisotropic magnetic dipole-dipole interaction and the second-order spin-orbit coupling can play important roles, inducing couplingbetween the spin and the orbital motion. They measured the spin-relaxing collision rate to be approximately 5 orders of magnitude higher than the charge-exchange collision rate \cite{kohl13}. Regarding the measured radiative charge transfer collision rate, we find that our calculation is in very good agreement with experiment and with previous calculations. Nonetheless, we find no broad resonances features that might underly a strong isotope effect. In conclusion, we find, in agreement with previous theory that the isotope anomaly observed in experiment remains an open question.Comment: 7 figures, 1 table accepted for publication in J. Phys. B: At. Mol. Opt. Phys. arXiv admin note: text overlap with arXiv:1107.114

    Dry matter yields and quality of organic lupin/cereal mixtures for wholecrop forage

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    In view of climate change predictions and the general desirability of increasing the amount of home grown protein, a case exists for the investigation of lupins and lupin/cereal bicrop combinations as wholecrop forage on organic farms. A replicated randomised block trial is described which took place at the Royal Agricultural College, Cirencester, in 2005. This involved spring sown blue, white and yellow lupins, millet, wheat and triticale and lupin/cereal bi-crops. Data for dry matter yields for wholecrop silage, crude protein, MAD fi bre content and estimated ME, are presented for a single harvest. It is concluded that white lupins and white lupin bi-crops with spring wheat or triticale offer the best prospects for a viable wholecrop forage crop in an organic situation
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