We analyze the lattice SU(2) Yang-Mills theory in Coulomb gauge. We show that the static gluon propagator is multiplicative renormalizable and takes the simple form D(| p|) −1 = | p| 2 + M 4 /| p| 2 , proposed by Gribov through heuristic arguments many years ago. We find M = 0.88(1)GeV 2 √ σ.

We measured interleukin-6 (IL-6) levels in 70 serum samples obtained from 25 patients with systemiconset juvenile rheumatoid arthritis (JRA), using the hybridoma cell line B9. Patients with systemic-onset JRA had significantly elevated serum IL-6 levels during active disease (mean f SD 92.1 2 75.1 hybridoma growth factor unitdml; P < O. OOOO1 versus healthy age-matched controls), but not during remission. Serum IL-6 levels correlated with the extent and severity of joint involvement (P < 0.001) and with platelet counts (P C 0.05). Our data suggest that IL-6 plays a significant role in the pathogenesis of systemic-onset JRA.The systemic onset form of juvenile rheumatoid arthritis (JRA) is characterized by the presence of chronic arthritis associated with high spiking fever, and is frequently accompanied by other systemic symptoms including evanescent cutaneous rash, hepatosplenomegaly , lymphadenomegaly , and serositis (1,2). The typical fever pattern is characterized by the presence of one or two daily spikes, usually in the late afternoon or evening; most patients are afebrile in the morning. There is prominent laboratory evidence of inflammation, including marked elevation of the erythrocyte sedimentation rate (ESR) and of acute-phase

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We reinvestigate the problem of Gribov ambiguities within the Landau (or Lorentz) gauge for the ghost and gluon propagators in pure SU (2) lattice gauge theory. We make use of the full symmetry group of the action taking into account large, i.e. non-periodic Z(2) gauge transformations leaving lattice plaquettes invariant. Enlarging in this way the gauge orbits for any given gauge field configuration the Landau gauge can be fixed at higher local extrema of the gauge functional in comparison with standard (overrelaxation) techniques. This has a clearly visible effect not only for the ghost propagator at small momenta but also for the gluon propagator, in contrast to the common belief.

We report on very strong evidence of the occurrence of power terms in α MOM (p), the QCD running coupling constant in the M OM scheme, by analyzing non-perturbative measurements from the lattice threegluon vertex between 2.0 and 10.0 GeV at zero flavor. While putting forward the caveat that this definition of the coupling is a gauge dependent one, the general relevance of such an occurrence is discussed. We fit Λ (n f =0) MS = 237± 3 + 0 −10 MeV in perfect agreement with the result obtained by the ALPHA group with a totally different method. The power correction to α MOM (p) is fitted to (0.63 ± 0.03 + 0.0 − 0.13 ) GeV 2 /p 2 .

Subjects with Down syndrome (DS) have a high mortality due to infections and a high risk of developing malignancies. These observations, together with the demonstration of a frequent occurrence of HBsAg carrier state and of autoantibodies, have prompted investigations of the immune function in DS. Thymic morphological and functional abnormalities have been demonstrated. Peripheral blood mononuclear cells of DS subjects have been shown to include a high number of T lymphocytes with low avidity for sheep erythrocytes and a very high percentage of cells with an NK phenotype. However, NK activity is low in DS. Production of some important cytokines, such as IL‐2, is depressed, thus contributing to T‐cell derangement. Abnormalities of the B‐cell compartment were also demonstrated, with a tendency towards high IgG and low IgM serum levels. Controversial results have been obtained with regard to antigen‐specific antibody response. Also phagocytes of DS subjects display some characteristic functional impairments, with low chemotactic ability and reduced production of oxygen radicals. Despite the clearly established and rather detailed evidence of immune derangements, therapeutic trials have been anecdotal and resulted in marginal effects. HBV vaccination is highly advisable in DS because of the high risk of becoming chronic HBV carriers once infected.

Immunologic studies were performed in 83 patients with Down's Syndrome (DS) in ages ranging from a few months to 30 years and 76 karyotypically normal age-matched controls. The results show that both thymus-dependent and independent functions were impaired in DS with a characteristic age sequence. Serum immunoglobulin levels were normal in children with DS less then 5 years old; after 6 years of age a definite hyperglobulinemia of the IgG and IgA type was observed. A slight decrease in IgM was observed between 16 and 25 years of age. In subjects with DS lymphocyte phytohemagglutinin responsiveness was in the normal range during the first decade but it decreased thereafter progressively; the percentage and absolute number of peripheral blood lymphocytes forming "spontaneous rosettes" with sheep erythrocytes were abnormally low at all ages including infancy; the number of circulating lymphocytes with a high density of surface immunoglobulins was always in the normal range.

For the gluon propagator of pure SU (2) lattice gauge theory in the Landau gauge we investigate the effect of Gribov copies and finite-volume effects. Concerning gauge fixing, we enlarge the accessible gauge orbits by adding nonperiodic Z(2) gauge transformations and systematically employ the simulated annealing algorithm. Strategies to keep all Z(2) sectors under control within reasonable CPU time are discussed. We demonstrate that the finite-volume effects in the infrared regime become ameliorated. Reaching a physical volume of about (6.5 fm) 4 , we find that the propagator, calculated with the indicated improvements, becomes flat in the region of smallest momenta. There are first signs in four dimensions of a decrease towards vanishing momentum.