New methods in conformal partial wave analysis

We report on progress concerning the partial wave analysis of higher correlation functions in conformal quantum field theory.Comment: 16 page

Analytic structure of meson propagators in the proper-time regularized Nambu--Jona-Lasinio model

We analyze the analytic structure of meson propagators in the Nambu--Jona-Lasinio model with a proper-time regulator. We show that the regulator produces unphysical complex singularities. As a result the naive use of the Wick rotation is no longer allowed. Formulas involving integration over mesonic momenta, such as meson-loop contributions or dispersion relations for meson Green's functions, cannot be written in usual forms.Comment: revised versio

Unitary Positive-Energy Representations of Scalar Bilocal Quantum Fields

The superselection sectors of two classes of scalar bilocal quantum fields in D>=4 dimensions are explicitly determined by working out the constraints imposed by unitarity. The resulting classification in terms of the dual of the respective gauge groups U(N) and O(N) confirms the expectations based on general results obtained in the framework of local nets in algebraic quantum field theory, but the approach using standard Lie algebra methods rather than abstract duality theory is complementary. The result indicates that one does not lose interesting models if one postulates the absence of scalar fields of dimension D-2 in models with global conformal invariance. Another remarkable outcome is the observation that, with an appropriate choice of the Hamiltonian, a Lie algebra embedded into the associative algebra of observables completely fixes the representation theory.Comment: 27 pages, v3: result improved by eliminating redundant assumptio

Infinite dimensional Lie algebras in 4D conformal quantum field theory

The concept of global conformal invariance (GCI) opens the way of applying algebraic techniques, developed in the context of 2-dimensional chiral conformal field theory, to a higher (even) dimensional space-time. In particular, a system of GCI scalar fields of conformal dimension two gives rise to a Lie algebra of harmonic bilocal fields, V_m(x,y), where the m span a finite dimensional real matrix algebra M closed under transposition. The associative algebra M is irreducible iff its commutant M' coincides with one of the three real division rings. The Lie algebra of (the modes of) the bilocal fields is in each case an infinite dimensional Lie algebra: a central extension of sp(infty,R) corresponding to the field R of reals, of u(infty,infty) associated to the field C of complex numbers, and of so*(4 infty) related to the algebra H of quaternions. They give rise to quantum field theory models with superselection sectors governed by the (global) gauge groups O(N), U(N), and U(N,H)=Sp(2N), respectively.Comment: 16 pages, with minor improvements as to appear in J. Phys.

ANTIBODIES DIRECTED TO INDIVIDUAL HISTONES IN JUVENILE CHRONIC ARTHRITIS. ASSOCIATION WITH UVEITIS

The trials for identification of the specific target antigen for antinuclear antibodies (ANA) in juvenile chronic arthritis (JCA) revealed that a significant number of patients produce antibodies directed to individual histories and histone peptides. Fifty JCA patients, 58 healthy children and 58 children with autoimmune and rheumatologic disorders were studied for a presence of IgG- and IgM-antibodies against histone 1, histone 2 and histone 3 measured by ELISA. The levels of IgGand IgM-antibodies directed to histone 1, 2 and 3 were elevated in JCA as compared to the healthy controls. IgG-antibodies to histone 2 and IgM-antibodies to histone 3 also were elevated in comparison with the disease controls. IgG- and IgM-antibodies against histone 1 were found to be positive in 30 % and 26 % of JCA patients, respectively, in significant association with ANA (p = 0,038 and p = 0,03, respectively) and uveitis (p = 0,02 and p = 0,016, respectively). The same prevalence of IgG- and IgM-antibodies to histone 2 was established but only the IgG-isotype showed significant association with uveitis (p = 0,018). Anti-histone 3 IgG- and IgM-antibodies were found in 34 % and 27 % of JCA patients, respectively. IgM-antibodies to histone 3 were proved to be significantly associated with uveitis (p - 0,009). It was concluded that antibodies to histone 1, histone 2, and histone 3 represented a common serological feature of JCA. Their presence was related to the manifestation of chronic anterior uveitis, associated with JCA

UNDERSTANDING CAPTURE EFFICIENCY IN FLUIDIZED BEDS

This paper describes an experimental study on the extent of capture efficiency in a fluidized bed system under controlled conditions. Using aerosols as tracer compound, the capture efficiency in a fluidized bed was quantitatively measured as a function of contact distance (time). The paper presents the experimental technique as well as the results relating the capture efficiency to the bed hydrodynamic. A theoretical model was developed to describe the influence of operating variables on the overall capture efficiency. Dominant mechanisms enabling the capture of the fine aerosols are elucidated