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The Hannay geometric phase is the classical analog of the well-known Berry phase. Its most familiar example is the effect of the latitude λ on the motion of a Foucault pendulum. We describe an electronic network whose behavior is exactly equivalent to that of the pendulum. The circuit can be constructed from off-the-shelf components using two matched transconductance amplifiers that comprise a gyrator to introduce the non-reciprocal behavior needed to mimic the pendulum. One may precisely measure the dependence of the Hannay phase on λ by circuit simulation and by laboratory measurements on a constructed circuit. [ABSTRACT FROM AUTHOR]

We show that due to the large coupling constant of the monopole-photon interaction the annihilation of monopole-antimonopole and monopolium into many photons must be considered experimentally. For monopole-antimonopole annihilation and lightly bound monopolium, even in the less favorable scenario, multiphoton events (four and more photons in the final state) are dominant, while for strongly bound monopolium, although two photon events are important, four- and six-photon events are also sizable. [ABSTRACT FROM AUTHOR]

Generalized parton distribution functions (GPDs) are calculated in a field theoretic formalism using a covariant Bethe-Salpeter approach. The procedure is described in an exact calculation in scalar Electrodynamics, and then extended to the Nambu–Jona-Lasinio model. In both cases we demonstrate that all important features required by general physical considerations, like symmetry properties, sum rules and the polynomiality condition, are explicitly verified. [Copyright &y& Elsevier]

The momentum distribution of Λ0 hyperons produced from the quark-gluon plasma (QGP) in ultra-relativistic heavy-ion collisions is calculated in dependence on their polarization. The momentum distribution of Λ0 hyperons is defined by matrix elements of relativistic quark Wigner operators, which are calculated within the effective quark model with chiral U(3)×U(3) symmetry and the quark-gluon transport theory. We show that the polarization of the Λ0 hyperon depends on the spin of the strange quark that agrees well with the DeGrand-Miettinen model. We show that Λ0 hyperons, produced from the QGP, are fully unpolarized. This means that a detection of unpolarized Λ0 hyperons, produced in ultra-relativistic heavy-ion collisions, should serve as one of the signatures for the existence of the QGP in intermediate states of ultra-relativistic heavy-ion collisions. [ABSTRACT FROM AUTHOR]

Nonperturbative QCD mechanisms are of fundamental importance in strong interaction physics. In particular, the flavor singlet axial anomaly leads to a gluonic pole mechanism which has been shown to explain the η′ mass, violations of the OZI rule and more recently the proton spin. We analyze under which conditions the interaction derived from the gluonic pole exchange might explain the high momentum transfer behavior of the photoproduction cross sections of vector mesons at JLab energies. We provide therefore additional support to our scenario in which nonperturbative QCD mechanisms are relevant for the interpretation of the data. [Copyright &y& Elsevier]

Double parton distribution functions (dPDF) represent a tool to explore the 3D proton structure. They can be measured in high energy proton-proton and proton nucleus collisions and encode information on how partons inside a proton are correlated among each other. dPFDs are studied here in the valence quark region, by means of a constituent quark model, where two particle correlations are present without any additional prescription. This framework allows to understand the dynamical origin of the correlations and to clarify which, among the features of the results, are model independent. Use will be made of a relativistic light-front scheme, able to overcome some drawbacks of the previous calculation. Transverse momentum correlations, due to the exact treatment of the boosts, are predicted and analyzed. The role of spin correlations is also shown. Due to the covariance of the approach, some symmetries of the dPDFs are seen unambigously. For the valence sector, also the study of the QCD evolution of the model results, which can be performed safely thanks to the property of good support, has been also completed.

Abstract: The role of quark correlations in the description of hadron dynamics in many domains of physics, from low energy dynamics to very hot (dense) systems, is being appreciated. Strong correlations of two quarks (diquark) have been widely investigated in this respect. Recently, we have proposed a dynamical scheme to describe the pentaquark in which also three quark correlations (triquark) were instrumental in producing a low mass exotic state. We perform a study, within the QCD sum rule approach including OPE and direct instanton contributions, of triquark correlations and obtain two quasi-bound light color quark clusters of 800 and 930 MeV, respectively. [Copyright &y& Elsevier]

We analyze the existence of the exotic Θ+ from the perspective of instanton induced quark dynamics. The ''t Hooft interaction gives strong attraction in specific channels of the triquark ud&smacr; and diquark ud configurations. In particular it leads to a light ud&smacr; triquark cluster, with the mass around 750 MeV, in the I=0, S=1/2 and color 3 configuration, and a light ud-diquark configuration, with mass 440 MeV, in the I=0, S=0 and color &3macr; configuration. If we consider the pentaquark as a bound state of such triquark and diquark configurations in a relative L=1 state we obtain good agreement with the data. The small width of Θ+ has a natural explanation in this model. [Copyright &y& Elsevier]

As primary biliary colangitis (PBC) is a autoimmune condition usually diagnosed between the fourth and sixth decades of life and its most common presentation is as a cholestatic jaundice, the diagnosis of acute hepatitis due to syphilis was considered more likely and treatment with penicillin G benzathine was offered. She was discharged to a primary care unit for follow up. B Discussion: b Acute hepatitis is one of the atypical presentations of primary and secondary syphilis. Liver tests normalized one month after therapy and VDRL title dropped to 1/128, while ANA and AMA tested negative. [Extracted from the article]