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Bargaining over perfect complements owned separately: with experimental test
This paper considers the situation in which two perfect complements belong to different owners. We calculate the Bayesian–Nash equilibrium in the mechanism of k + 1 − price bargaining with private value, and did experiment to test the theory
Application of unstrained flamelet SGS closure for multi-regime premixed combustion
Large eddy simulation of turbulent premixed combustion behind a bluff-body is performed using unstrained flamelet model with a presumed probability density function to calculate filtered reaction rate. The subgrid variance of the progress variable required in this approach is calculated using its transport equation to include contributions from reaction, turbulence and molecular diffusive and dissipative processes at sub-grid scales. The dissipation rate of the variance is obtained using an algebraic closure, which maintains physical consistency among turbulence, reaction and molecular diffusion. Various quantities such as mean velocity, temperature and species mass fractions computed for two bluff-body flames experiencing 2% and 24% turbulence intensities are compared to their respective measurements. These comparisons are very good suggesting that the unstrained flamelet SGS closure works well for multi-regime combustion. The demonstrated success of this modelling framework is explained on a physical basis.Engineering and Physical Sciences Research Council (Grant ID: EP/I027556/1), Siemens, Rolls-Royc
Pygmy Dipol Resonances as a Manifestation of the Structure of the Neutron-Rich Nuclei
Dipole excitations in neutron-rich nuclei below the neutron threshold are
investigated. The method is based on Hartree-Fock-Bogoliubov (HFB) and
Quasiparticle-Phonon Model (QPM) theory. Of our special interest are the
properties of the low-lying 1- Pygmy Resonance and the two-phonon
quadrupole-octupole 1- states in Sn-isotopes including exploratory
investigations for the experimentally unknown mass regions. In particular we
investigate the evolution of the dipole strength function with the neutron
excess. The use of HFB mean-field potentials and s.p. energies is found to
provide a reliable extrapolation into the region off stability.Comment: 8 pages, 3 figures, Proceedings of the International Conference on
Collective Motion in Nuclei Under Extreme Conditions (COMEX1), Paris, France,
10-13 June 200
Comparison between four published definitions of hyposmia in Parkinson's disease
Objectives: Hyposmia is a common feature of Parkinson's disease (PD), yet there is no standard method to define it. A comparison of four published methods was performed to explore and highlight differences. //
Materials and methods: Olfactory testing was performed in 2097 cases of early PD in two prospective studies. Olfaction was assessed using various cut-offs, usually corrected by age and/or gender. Control data were simulated based on the age and gender structure of the PD cases and published normal ranges. Association with age, gender, and disease duration was explored by method and study cohort. Prevalence of hyposmia was compared with the age and gender-matched simulated controls. Between method agreement was measured using Cohen's kappa and Gwet's AC1. //
Results: Hyposmia was present in between 69.1% and 97.9% of cases in Tracking Parkinson's cases, and between 62.2% and 90.8% of cases in the Parkinson's Progression Marker Initiative, depending on the method. Between-method agreement varied (kappa 0.09–0.80, AC1 0.55–0.86). The absolute difference between PD cases and simulated controls was similar for men and women across methods. Age and male gender were positively associated with hyposmia (p < .001, all methods). Odds of having hyposmia increased with advancing age (OR:1.06, 95% CI:1.03, 1.10, p < .001). Longer disease duration had a negative impact on overall olfactory performance. //
Conclusions: Different definitions of hyposmia give different results using the same dataset. A standardized definition of hyposmia in PD is required, adjusting for age and gender, to account for the background decline in olfactory performance with ageing, especially in men
Orbital M1 versus E2 strength in deformed nuclei: A new energy weighted sum rule
Within the unified model of Bohr and Mottelson we derive the following linear
energy weighted sum rule for low energy orbital 1 excitations in even-even
deformed nuclei S_{\rm LE}^{\rm lew} (M_1^{\rm orb}) \cong (6/5) \epsilon
(B(E2; 0^+_1 \rightarrow 2_1^+ K=0)/Z e^2^2) \mu^2_N with B(E2) the E2
strength for the transition from the ground state to the first excited state in
the ground state rotational band, the charge r.m.s. radius squared and
the binding energy per nucleon in the nuclear ground state. It is
shown that this energy weighted sum rule is in good agreement with available
experimental data. The sum rule is derived using a simple ansatz for the
intrinsic ground state wave function that predicts also high energy 1
strength at 2 carrying 50\% of the total moment of the
orbital M1 operator.Comment: REVTEX (3.0), 9 pages, RU924
Transition Rates between Mixed Symmetry States: First Measurement in 94Mo
The nucleus 94Mo was investigated using a powerful combination of
gamma-singles photon scattering experiments and gamma-gamma-coincidence studies
following the beta-decay of 94mTc. The data survey short-lived J^pi=1+,2+
states and include branching ratios, E2/M1 mixing ratios, lifetimes, and
transition strengths. The mixed-symmetry (MS) 1+ scissors mode and the 2+ MS
state are identified from M1 strengths. A gamma transition between MS states
was observed and its rate was measured. Nine M1 and E2 strengths involving MS
states agree with the O(6) limit of the interacting boson model-2 using the
proton boson E2 charge as the only free parameter.Comment: 9 pages, 3 PostScript figures included, ReVTeX, accepted for
publication in Physical Review Letters, tentatively scheduled for August 9,
199
Strong fragmentation of low-energy electromagnetic excitation strength in Sn
Results of nuclear resonance fluorescence experiments on Sn are
reported. More than 50 transitions with MeV were
detected indicating a strong fragmentation of the electromagnetic excitation
strength. For the first time microscopic calculations making use of a complete
configuration space for low-lying states are performed in heavy odd-mass
spherical nuclei. The theoretical predictions are in good agreement with the
data. It is concluded that although the E1 transitions are the strongest ones
also M1 and E2 decays contribute substantially to the observed spectra. In
contrast to the neighboring even Sn, in Sn the
component of the two-phonon quintuplet built on top of
the 1/2 ground state is proved to be strongly fragmented.Comment: 4 pages, 3 figure
Nuclear Scissors Mode with Pairing
The coupled dynamics of the scissors mode and the isovector giant quadrupole
resonance are studied using a generalized Wigner function moments method taking
into account pair correlations. Equations of motion for angular momentum,
quadrupole moment and other relevant collective variables are derived on the
basis of the time dependent Hartree-Fock-Bogoliubov equations. Analytical
expressions for energy centroids and transitions probabilities are found for
the harmonic oscillator model with the quadrupole-quadrupole residual
interaction and monopole pairing force. Deformation dependences of energies and
values are correctly reproduced. The inclusion of pair correlations
leads to a drastic improvement in the description of qualitative and
quantitative characteristics of the scissors mode.Comment: 36 pages, 5 figures, the results of calculation by another method and
the section concerning currents are adde
High-energy scissors mode
All the orbital M1 excitations, at both low and high energies, obtained from
a rotationally invariant QRPA, represent the fragmented scissors mode. The
high-energy M1 strength is almost purely orbital and resides in the region of
the isovector giant quadrupole resonance. In heavy deformed nuclei the
high-energy scissors mode is strongly fragmented between 17 and 25 MeV (with
uncertainties arising from the poor knowledge of the isovector potential). The
coherent scissors motion is hindered by the fragmentation and for single transitions in this region. The cross
sections for excitations above 17 MeV are one order of magnitude larger for E2
than for M1 excitations even at backward angles.Comment: 20 pages in RevTEX, 5 figures (uuencoded,put with 'figures') accepted
for publication in Phys.Rev.
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