Induction and suppression of an autoimmune disease by oligomerized T cell epitopes: enhanced in vivo potency of encephalitogenic peptides

T cell epitope peptides derived from proteolipid protein (PLP139-151) or myelin basic protein (MBP86-100) induce experimental autoimmune encephalomyelitis (EAE) in "susceptible" strains of mice (e.g., SJL/J). In this study, we show that the encephalitogenic effect of these epitopes when injected subcutaneously in complete Freund's adjuvant was significantly enhanced if administered to the animal in a multimerized form as a T cell epitope oligomer (i.e., as multiple repeats of the peptide epitope, such as 16-mers). Oligomer-treated SJL/J mice developed EAE faster and showed a more severe progression of the disease than animals treated with peptide alone. In addition, haplotype-matched B10.S mice, "resistant" to EAE induction by peptide, on injection of 16-mers developed a severe form of EAE. Even more striking, however, was the dramatic suppression of incidence and severity of the disease, seen after single intravenous injections of only 50 microg of the PLP139-151 16-mer, administered to SJL/J mice 7 d after the induction of the disease. Although relapse occurred at about day 45, an additional injection several days before that maintained the suppression. Importantly, the specific suppressive effect of oligomer treatment was also evident if EAE was induced with spinal cord homogenate instead of the single peptide antigen. By contrast, the PLP139-151 peptide accelerated rather than retarded the progression of disease

Analyticity Properties and Unitarity Constraints of Heavy Meson Form Factors

We derive new bounds on the b-number form factor $F(q^2)$ of the B meson. (Revised version of hep-ph/9306214).Comment: 22 page

Shear yielding of amorphous glassy solids: Effect of temperature and strain rate

We study shear yielding and steady state flow of glassy materials with molecular dynamics simulations of two standard models: amorphous polymers and bidisperse Lennard-Jones glasses. For a fixed strain rate, the maximum shear yield stress and the steady state flow stress in simple shear both drop linearly with increasing temperature. The dependence on strain rate can be described by a either a logarithm or a power-law added to a constant. In marked contrast to predictions of traditional thermal activation models, the rate dependence is nearly independent of temperature. The relation to more recent models of plastic deformation and glassy rheology is discussed, and the dynamics of particles and stress in small regions is examined in light of these findings

A Systematic Analysis of the Lepton Polarization Asymmetries in the Rare B Decay, B -> X_s\tau^+\tau^-

The most general model-independent analysis of the lepton polarization asymmetries in the rare B decay, \Bstt, is presented. We present the longitudinal, normal and transverse polarization asymmetries for the $\tau^+$ and $\tau^-$, and combinations of them, as functions of the Wilson coefficients of twelve independent four-Fermi interactions, ten of them local and two nonlocal. These procedures will tell us which type of operators contributes to the process. And it will be very useful to pin down new physics systematically, once we have the experimental data with high statistics and a deviation from the Standard Model is found.Comment: 24 pages, 8 figures, LaTe

Final-State Phases in Doubly-Cabibbo-Suppressed Charmed Meson Nonleptonic Decays

Cabibbo-favored nonleptonic charmed particle decays exhibit large final-state phase differences in $\bar K \pi$ and $\bar K^* \pi$ but not $\bar K \rho$ channels. It is of interest to know the corresponding pattern of final-state phases in doubly-Cabibbo-suppressed decays, governed by the $c \to d u \bar s$ subprocess. An experimental program is outlined for determining such phases via measurements of rates for $D \to K^* \pi$ and $K (\rho, \omega,\phi)$ channels, and determination of interference between bands in Dalitz plots. Such a program is feasible at planned high-intensity sources of charmed particles.Comment: 12 pages, LaTeX, 2 figures, to be submitted to Phys. Rev. D. Revised versio

CP Phases in Correlated Production and Decay of Neutralinos in the Minimal Supersymmetric Standard Model

We investigate the associated production of neutralinos $e^+e^-\to\tilde{\chi}^0_1\tilde{\chi}^0_2$ accompanied by the neutralino leptonic decay $\tilde{\chi}^0_2\to\tilde{\chi}^0_1 \ell^+\ell^-$, taking into account initial beam polarization and production-decay spin correlations in the minimal supersymmetric standard model with general CP phases but without generational mixing in the slepton sector. The stringent constraints from the electron EDM on the CP phases are also included in the discussion. Initial beam polarizations lead to three CP--even distributions and one CP--odd distribution, which can be studied independently of the details of the neutralino decays. We find that the production cross section and the branching fractions of the leptonic neutralino decays are very sensitive to the CP phases. In addition, the production--decay spin correlations lead to several CP--even observables such as lepton invariant mass distribution, and lepton angular distribution, and one interesting T--odd (CP--odd) triple product of the initial electron momentum and two final lepton momenta, the size of which might be large enough to be measured at the high--luminosity future electron--positron collider or can play a complementary role in constraining the CP phases with the EDM constraints.Comment: Revtex, 37 pages, 12 eps figure

Supersymmetric CP Violation in B→Xsl+l−B \to X_s l^+ l^- in Minimal Supergravity Model

Direct CP asymmetries and the CP violating normal polarization of lepton in inclusive decay B \to X_s l^+ l^- are investigated in minimal supergravity model with CP violating phases. The contributions coming from exchanging neutral Higgs bosons are included. It is shown that the direct CP violation in branching ratio, A_{CP}^1, is of {\cal{O}}(10^{-3}) for l=e, \mu, \tau. The CP violating normal polarization for l=\mu can reach 0.5 percent when tan\beta is large (say, 36). For l=\tau and in the case of large \tan\beta, the direct CP violation in backward-forward asymmetry, A_{CP}^2, can reach one percent, the normal polarization of \tau can be as large as a few percent, and both are sensitive to the two CP violating phases, \phi_\mu and \phi_{A_0}, and consequently it could be possible to observe them (in particular, the normal polarization of \tau) in the future B factories.Comment: 14 pages, latex, 5 figure

Measuring the Relative Strong Phase in D0→K∗+K−D^0 \to K^{*+} K^- and D0→K∗−K+D^0 \to K^{*-} K^+ Decays

In a recently suggested method for measuring the weak phase $\gamma$ in $B^\pm \to K^\pm (KK^*)_D$ decays, the relative strong phase $\delta_D$ in $D^0 \to K^{*+} K^-$ and $D^0 \to K^{*-} K^+$ decays (equivalently, in $D^0 \to K^{*+} K^-$ and \od \to K^{*+} K^-) plays a role. It is shown how a study of the Dalitz plot in $D^0 \to K^+ K^- \pi^0$ can yield information on this phase, and the size of the data sample which would give a useful measurement is estimated.Comment: 13 pages, latex, 5 figures, submitted to Phys. Rev. D. Appendix and some text on additional resonant contributions adde

Simply Modeling Meson HQET

A simple relativistic model of heavy-quark-light-quark mesons is proposed. In an expansion in inverse powers of the heavy quark mass we find that all zeroth and first order heavy quark symmetry relations are satisfied. The main results are: - the difference between the meson mass and the heavy quark mass plays a significant role even at zeroth order; - the slope of the Isgur-Wise function at the zero recoil point is typically less than $-1$; - the first order correction to the pseudoscalar decay constant is large and negative; - the four universal functions describing the first order corrections to the semileptonic decay form factors are small; - these latter corrections are quite insensitive to the choice of model parameters, and in particular to the effects of hyperfine mass splitting.Comment: 17 pages, LaTeX, 3 LaTeX figures in separate file, UTPT-92-16. This is the version published long ago but not previously archive