79 research outputs found
Equivariant comparison of quantum homogeneous spaces
We prove the deformation invariance of the quantum homogeneous spaces of the
q-deformation of simply connected simple compact Lie groups over the
Poisson-Lie quantum subgroups, in the equivariant KK-theory with respect to the
translation action by maximal tori. This extends a result of Neshveyev-Tuset to
the equivariant setting. As applications, we prove the ring isomorphism of the
K-group of Gq with respect to the coproduct of C(Gq), and an analogue of the
Borsuk-Ulam theorem for quantum spheres.Comment: 21 page
The deconfining phase transition in full QCD with two dynamical flavors
We investigate the deconfining phase transition in SU(3) pure gauge theory
and in full QCD with two flavors of staggered fermions. The phase transition is
detected by measuring the free energy in presence of an abelian monopole
background field. In the pure gauge case our finite size scaling analysis is in
agreement with the well known presence of a weak first order phase transition.
In the case of 2 flavors full QCD we find, using the standard pure gauge and
staggered fermion actions, that the phase transition is consistent with weak
first order, contrary to the expectation of a crossover for not too large quark
masses and in agreement with results obtained by the Pisa group.Comment: 23 pages, 11 figures, 4 tables (minor typos corrected, references
updated, accepted for publication on JHEP
The equation of state for two flavor QCD at N_t=6
We calculate the two flavor equation of state for QCD on lattices with
lattice spacing a=(6T)^{-1} and find that cutoff effects are substantially
reduced compared to an earlier study using a=(4T)^{-1}. However, it is likely
that significant cutoff effects remain. We fit the lattice data to expected
forms of the free energy density for a second order phase transition at
zero-quark-mass, which allows us to extrapolate the equation of state to m_q=0
and to extract the speed of sound. We find that the equation of state depends
weakly on the quark mass for small quark mass.Comment: 24 pages, latex, 11 postscipt figure
Transition from a quark-gluon plasma in the presence of a sharp front
The effect of a sharp front separating the quark-gluon plasma phase from the
hadronic phase is investigated. Energy-momentum conservation and baryon number
conservation constrain the possible temperature jump across the front. If one
assumes that the temperature in the hadronic phase is 200 MeV , as
has been suggested by numerous results from relativistic ion collisions, one
can determine the corresponding temperature in the quark phase with the help of
continuity equations across the front. The calculations reveal that the quark
phase must be in a strongly supercooled state. The stability of this solution
with respect to minor modifications is investigated. In particular the effect
of an admixture of hadronic matter in the quark phase (e.g. in the form of
bubbles) is considered in detail. In the absence of admixture the transition
proceeds via a detonation transition and is accompanied by a substantial
super-cooling of the quark-gluon plasma phase. The detonation is accompanied by
less supercooling if a small fraction of bubbles is allowed. By increasing the
fraction of bubbles the supercooling becomes weaker and eventually the
transition proceeds via a smoother deflagration wave.Comment: 10 pages, manuscript in TeX, 9 figures available as Postscript files,
CERN-TH 6923/9
Social Support and Health: A Theoretical Formulation Derived from King's Conceptual Framework
This article describes the development and initial empirical testing of a theoretical formulation of social support, family, health, and child health derived from Imogene King's conceptual framework for nursing. A correlational design was used to test the formulation with 103 families who have children with diabetes mellitus. Three hypotheses were sup ported : parents' social support had a direct and positive effect on family health, parents' social support and child's social support were positively related, and illness factors had a direct and negative effect on child health. Both the supported and unsupported hypotheses are discussed in terms of the present substantive knowledge base and evidence of validity for King's framework. Direction for further theory development and research are identified.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68995/2/10.1177_089431848900200309.pd
Mathematics of Gravitational Lensing: Multiple Imaging and Magnification
The mathematical theory of gravitational lensing has revealed many generic
and global properties. Beginning with multiple imaging, we review
Morse-theoretic image counting formulas and lower bound results, and
complex-algebraic upper bounds in the case of single and multiple lens planes.
We discuss recent advances in the mathematics of stochastic lensing, discussing
a general formula for the global expected number of minimum lensed images as
well as asymptotic formulas for the probability densities of the microlensing
random time delay functions, random lensing maps, and random shear, and an
asymptotic expression for the global expected number of micro-minima. Multiple
imaging in optical geometry and a spacetime setting are treated. We review
global magnification relation results for model-dependent scenarios and cover
recent developments on universal local magnification relations for higher order
caustics.Comment: 25 pages, 4 figures. Invited review submitted for special issue of
General Relativity and Gravitatio
Modeling, optimizing and simulating robot calibration with accuracy improvement
This work describes techniques for modeling, optimizing and simulating calibration processes ofrobots using off-line programming. The identification of geometric parameters of the nominalkinematic model is optimized using techniques of numerical optimization of the mathematicalmodel. The simulation of the actual robot and the measurement system is achieved by introducingrandom errors representing their physical behavior and its statistical repeatability. An evaluationof the corrected nominal kinematic model brings about a clear perception of the influence ofdistinct variables involved in the process for a suitable planning, and indicates a considerableaccuracy improvement when the optimized model is compared to the non-optimized one
Spaces of Local Vector Fields
. Vector fields defined only over a part of a manifold give rise to indexes and to transfers. These local vector fields form a topological space whose relation to configuration spaces was studied by Dusa McDuff, and whose higher dimensional homotopy and homology promise invariants of parametrized families of local vector fields. We show that the assignment of the transfer to the vector field gives a map from the space of local vector fields of M into Q(M + ) which stablizes into a homotopy equivalence. 1. Introduction A local vector field on a smooth manifold M consists of an open subset U of M \Gamma M and a tangent vector field ~u on U which has compact zero set. For technical reasons we include as part of the definition the condition that for all K 0, fxfflU j j~u(x)j Kg is compact. The homotopy definition of the Hopf index of a local vector field (U; ~u) is based on an embedding M ae R s and realizes the index as the degree of a self map of the sphere S s . This map has..
Enterobacteriaceae Sepsis Outcome Programme annual report, 2013
The Australian Group on Antimicrobial Resistance performs regular period-prevalence studies to monitor changes in antimicrobial resistance in selected enteric Gram-negative pathogens. The 2013 survey focussed for the first time on blood stream infections. Four thousand nine hundred and fifty-eight Enterobacteriaceae species were tested using commercial automated methods (Vitek® 2, BioMérieux; Phoenix™, BD). The results were analysed using Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints (January 2014). Of the key resistances, non-susceptibility to the third-generation cephalosporin, ceftriaxone, was found in 7.5%/7.5% (CLSI/EUCAST criteria respectively) of Escherichia coli; 6.3%/6.3% of Klebsiella pneumoniae, and 7.4%/7.4% of K. oxytoca. Non-susceptibility rates to ciprofloxacin were 10.3%/11.3% for E. coli, 4.6%/7.5% for K. pneumoniae, 0.6%/0.6% for K. oxytoca, and 3.6%/6.1% in Enterobacter cloacae. Resistance rates to piperacillin-tazobactam were 3.1%/6.2%, 4.2%/7.0%, 11.9% /12.6%, and 17.3% /22.2% for the same 4 species respectively. Fourteen isolates were shown to harbour a carbapenemase gene, 9 blaIMP, 3 blaKPC, and 2 blaNDM
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