4,574 research outputs found
Chiral Lagrangian and spectral sum rules for dense two-color QCD
We analytically study two-color QCD with an even number of flavors at high
baryon density. This theory is free from the fermion sign problem. Chiral
symmetry is broken spontaneously by the diquark condensate. Based on the
symmetry breaking pattern we construct the low-energy effective Lagrangian for
the Nambu-Goldstone bosons. We identify a new epsilon-regime at high baryon
density in which the quark mass dependence of the partition function can be
determined exactly. We also derive Leutwyler-Smilga-type spectral sum rules for
the complex eigenvalues of the Dirac operator in terms of the fermion gap. Our
results can in principle be tested in lattice QCD simulations.Comment: 24 pages, 1 table, no figur
Long time, large scale limit of the Wigner transform for a system of linear oscillators in one dimension
We consider the long time, large scale behavior of the Wigner transform
W_\eps(t,x,k) of the wave function corresponding to a discrete wave equation
on a 1-d integer lattice, with a weak multiplicative noise. This model has been
introduced in Basile, Bernardin, and Olla to describe a system of interacting
linear oscillators with a weak noise that conserves locally the kinetic energy
and the momentum. The kinetic limit for the Wigner transform has been shown in
Basile, Olla, and Spohn. In the present paper we prove that in the unpinned
case there exists such that for any the
weak limit of W_\eps(t/\eps^{3/2\gamma},x/\eps^{\gamma},k), as \eps\ll1,
satisfies a one dimensional fractional heat equation with . In the pinned case an analogous
result can be claimed for W_\eps(t/\eps^{2\gamma},x/\eps^{\gamma},k) but the
limit satisfies then the usual heat equation
An unusual foreign body migrating through time and tissues
BACKGROUND: Beside infections, foreign body incidences are amongst the most frequently encountered pathologies in pediatric otolaryngology. While inhaled foreign bodies represent an acute emergency, symptoms of ingested foreign bodies sometimes appear with some delay. Typically fishbones tend to go unnoticed in a first examination and become symptomatic by fever, odynodyspahgia and torticollis. Exceptionally, foreign bodies migrate and become manifest with a considerable delay. CASE REPORT: We present a case of a young girl who presented with an unusual foreign body which migrated through the cervical tissues causing repeated cervical tumescence's before being diagnosed. CONCLUSION: Repeated cervical abscesses or tumescence's in children or young patients should alert the treating physician to seek for an underlying pathology such as unnoticed foreign bodies or malformations (e.g. cysts). Further the scarce literature on these migrating foreign bodies is discussed
Idiopathic Phantosmia: Outcome and Clinical Significance
Background/Aim: Little is known about the clinical significance of phantosmia. The literature on phantosmia indicates that this symptom has a wide range of differential diagnoses. However, most cases of phantosmia remain of unknown origin. Our goal was to follow up patients with idiopathic phantosmia, with special regard to improvement rates and possible severe health conditions preceded by phantosmia of unknown origin. Methods: Forty-four patients with idiopathic phantosmia which had consulted our Ear-Nose-Throat Smell and Taste Clinic over the last 10 years were contacted by telephone and underwent a structured medical interview. Results: None of the patients had eveloped any severe health condition or Parkinson’s disease. More than 5 years after the occurrence of hantosmia, more than 50% of the patients experienced disappearance (31.8%) or improvement (25%). In the remaining cases, phantosmia did not change (38.7%) or became worse ( ! 5%). Conclusion: The main findings of the present study were that idiopathic phantosmia improves or disappears in almost two thirds of the patients after more than 5 years, and that idiopathic phantosmia seems to be more likely a harmless symptom rather than a reliable predictor of early Parkinson’s disease or other severe diseases.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
A Retrospective Look at the Sarbanes-Oxley Act of 2002- Has it accomplished its original purpose?
As a result of notable frauds including Enron, WorldCom and Waste Management, the United States Congress enacted the Sarbanes-Oxley Act of 2002 (SOX). The Act would forever change the accounting profession. After a little more than a decade, publicly traded companies have been able to create and implement policies and procedures to ensure compliance with the Act, specifically the provisions set forth in Section 404. Since all public companies have implemented SOX compliance together with other regulations imposed by the Internal Revenue Service and other regulatory agencies into their normal reporting routines, management of these companies have realized further benefits associated with SOX compliance. Because of these reported benefits many private companies have begun to voluntarily implement SOX-like policies and procedures into their own internal framework. This paper will discuss the perceptions of the enactment and implementation of the Act, the associated benefits derived from SOX compliance and reasons why private companies have begun voluntarily adopting SOX-like policiesprocedures and strategies
Thermal conductivity in harmonic lattices with random collisions
We review recent rigorous mathematical results about the macroscopic
behaviour of harmonic chains with the dynamics perturbed by a random exchange
of velocities between nearest neighbor particles. The random exchange models
the effects of nonlinearities of anharmonic chains and the resulting dynamics
have similar macroscopic behaviour. In particular there is a superdiffusion of
energy for unpinned acoustic chains. The corresponding evolution of the
temperature profile is governed by a fractional heat equation. In non-acoustic
chains we have normal diffusivity, even if momentum is conserved.Comment: Review paper, to appear in the Springer Lecture Notes in Physics
volume "Thermal transport in low dimensions: from statistical physics to
nanoscale heat transfer" (S. Lepri ed.
Smell and taste disorders
Smell and taste disorders can markedly affect the quality of life. In recent years we have become much better in the assessment of the ability to smell and taste. In addition, information is now available to say something about the prognosis of individual patients. With regard to therapy there also seems to be low but steady progress. Of special importance for the treatment is the ability of the olfactory epithelium to regenerate
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