Landau-Pomeranchuk-Migdal resummation for dilepton production

We consider the thermal emission rate of dileptons from a QCD plasma in the small invariant mass (Q^2 \sim \gs^2 T^2) but large energy (q^0 \gsim T) range. We derive an integral equation which resums multiple scatterings to include the LPM effect; it is valid at leading order in the coupling. Then we recast it as a differential equation and show a simple algorithm for its solution. We present results for dilepton rates at phenomenologically interesting energies and invariant masses.Comment: 19 pages, 7 postscript figures, test program available at http://www-spht.cea.fr/articles/T02/150/libLPM

Synchrotron radiation in a chromo-magnetic field

We study the generalization of QED synchrotron radiation to the QCD case with a chromomagnetic field using the Schwinger {\it et al} source method. It is shown that the QED case can be obtained as a special limit. The comparison with the path integral approach of Zakharov has shown consistent results.Comment: Accepted for publication in Phys. Rev.

Comment on ``Success of collinear expansion in the calculation of induced gluon emission''

We show that the arguments against our recent paper on the failure of the collinear expansion in the calculation of the induced gluon emission raised by X.N. Wang are either incorrect or irrelevant.Comment: 5 pages, 1 figur

Molecular characterization and susceptibility of methicillin-resistant and methicillin-susceptible Staphylococcus aureus isolates from hospitals and the community in Vladivostok, Russia

AbstractA prospective study was conducted during an 8-month period, from August 2006 to April 2007, to describe the epidemiology of Staphylococcus aureus-associated infections. In addition, the molecular characteristics, antimicrobial susceptibilities and antibiotic resistance determinants were identified in S. aureus isolates from hospitals and the community in Vladivostok, Russia. Among the 63 S. aureus isolates eligible for this study, methicillin resistance was observed in 48% (n = 30). Hospital-acquired strains accounted for 93% (28/30) of all methicillin-resistant S. aureus (MRSA) isolates. The major MRSA clone (sequence type (ST) 239, staphylococcal cassette chromosome mec (SCCmec) type III, Panton--Valentine leukocidin (PVL)-negative, with two related staphylococcal protein A gene (spa) types (types 3 and 351)) represented 90% of all of the MRSA isolates. This clone was multidrug-resistant, and 41% of isolates showed resistance to rifampicin. Community-acquired MRSA isolates (n = 2) were categorized as ST30, SCCmecIV, spa type 19, and PVL--positive, and as ST8, SCCmecIV, of a novel spa type 826, and PVL-negative. Eight different STs were detected among methicillin-susceptible S. aureus (MSSA) isolates, of which 55% were PVL--positive. One MSSA clone, which was categorized as ST121, spa type 273, and PVL--positive, caused fatal community-acquired pneumonia infections. The strains predominantly isolated in hospitals in Russia belonged to the multidrug-resistant Brazilian/Hungarian ST239 MRSA clone; however, this clone has new antibiotic susceptibilities. Additionally, the emergence of PVL--positive MSSA strains with enhanced virulence was observed, warranting continued surveillance

Enhanced Photoluminescence with Dielectric Nanostructures: A review

Abstract Resonant dielectric subwavelength structures made of high-refractive-index materials are an emerging powerful platform with unique advantages compared to plasmonic based nanostructures. Owing to the low ohmic losses, to their ability to localize optical near-field at nanoscale, and exciting both electric and magnetic resonant modes, high-index dielectric materials are being used in various applications. Starting from the first principles, we aim at showing how resonant dielectric nanostructures can be efficiently used to enhance photoluminescence signal from an excited molecule, and we review the most recent results present in the Literature

Distillable entanglement in d⊗dd\otimes d dimension

Distillable entanglement ($E_d$) is one of the acceptable measures of entanglement of mixed states. Based on discrimination through local operation and classical communication, this paper gives $E_d$ for two classes of orthogonal multipartite maximally entangled states.Comment: 6 page

2PI effective action and gauge invariance problems

The problem of maintaining gauge invariance when truncating the two particle irreducible (2PI) effective action has been studied recently by several authors. Here we give a simple and very general derivation of the gauge dependence identities for the off-shell 2PI effective action. We consider the case where the gauge is fixed by an arbitrary function of the quantum gauge field, subject only to the restriction that the Faddeev-Popov matrix is invertable. We also study the background field gauge. We address the role that these identies play in solving gauge invariance problems associated with physical quantities calculated using a truncated on-shell 2PI effective action.Comment: 11 pages, version accepted for publication in Eur. Phys. Jour.