다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Statistical physics has proven to be a fruitful framework to describe phenomena outside the realm of traditional physics. Recent years have witnessed an attempt by physicists to study collective phenomena emerging from the interactions of individuals as elementary units in social structures. A wide list of topics are reviewed ranging from opinion and cultural and language dynamics to crowd behavior, hierarchy formation, human dynamics, and social spreading. The connections between these problems and other, more traditional, topics of statistical physics are highlighted. Comparison of model results with empirical data from social systems are also emphasized.

Statistical physics of social dynamics

We have studied the three quark system in a relativized version of the quark potential model with chromodynamics. With parameters consistent with those of an analogous study of meson spectroscopy we obtain a successful description of the spectrum of baryons. The model naturally explains the apparent absence of spin‐orbit interactions in baryons.

Baryons in a relativized quark model with chromodynamics

Monthly Notices is one of the three largest general primary astronomical research publications. It is an international journal, published by the Royal Astronomical Society. This article 1 describes its publication policy and practice.

Monthly Notices of the Royal Astronomical Society

The discovery of a sizeable asymmetry in the $\overline{u}$ and $\overline{d}$ distributions in the proton was one of the more consequential experimental findings in hadron physics last century. Although widely believed to be related to the fundamental role of chiral symmetry in QCD, a definitive verification of this hypothesis has remained elusive. We propose a novel test of the role of chiral symmetry in generating the sea flavor asymmetry by comparing the $\overline{d}\ensuremath{-}\overline{u}$ content in the proton with that in the ${\mathrm{\ensuremath{\Delta}}}^{+}$ baryon, where a significant enhancement is expected around the opening of the $N\ensuremath{\pi}$ decay channel. Recent developments in lattice QCD suggest a promising way to test this prediction in the near future.

/pdf/flavor-symmetry-breaking-in-the-d-sea-2r03xzxiie.pdf

Flavor symmetry breaking in the Δ sea

A description of fragmentation functions which satisfy the momentum and isospin sum rules is presented in an effective quark theory. Concentrating on the pion fragmentation function, we first explain why the elementary (lowest order) fragmentation process q → qπ is completely inadequate to describe the empirical data, although the crossed process π → qq describes the quark distribution functions in the pion reasonably well. Taking into account cascadelike processes in a generalized jet-model approach, we then show that the momentum and isospin sum rules can be satisfied naturally, without the introduction of ad hoc parameters. We present results for the Nambu―Jona-Lasinio (NJL) model in the invariant mass regularization scheme and compare them with the empirical parametrizations. We argue that the NJL-jet model, developed herein, provides a useful framework with which to calculate the fragmentation functions in an effective chiral quark theory.

https://absimage.aps.org/image/HAW09/MWS_HAW09-2009-000080.pdf

The NJL-jet model for quark fragmentation functions

Physics at the Japan Hadron Facility

/pdf/generation-of-baryon-asymmetry-in-the-e-6-chm-553s17i3yl.pdf

Anthony W. Thomas

Papers

Flavor symmetry breaking in the Δ sea

The NJL-jet model for quark fragmentation functions

Physics at the Japan Hadron Facility

Generation of baryon asymmetry in the E 6 CHM

Progress in the calculation and experimental determination of the strangeness contributions to nucleon form factors