627 research outputs found

    Two-loop self-energy correction in high-Z hydrogen-like ions

    Get PDF
    A complete evaluation of the two-loop self-energy diagrams to all orders in Z\alpha is presented for the ground state of H-like ions with Z\ge 40.Comment: RevTeX, 5 figures, 1 tabl

    INTERACTIONS OF THE COMPLEMENT SYSTEM WITH ENDOTOXIC LIPOPOLYSACCHARIDE : GENERATION OF A FACTOR CHEMOTACTIC FOR POLYMORPHONUCLEAR LEUKOCYTES

    Get PDF
    Endotoxic lipopolysaccharide has recently been shown to fix large amounts of the complement components related to the biologic activities mediated by that system. The present study sought to determine whether the generation of chemotactic factor by endotoxin in serum was dependent upon complement system activation. Preheating serum, incubating at 0°C, or incubating in the presence of EDTA, all prevented chemotactic factor generation as well as complement fixation by endotoxin. "Endotoxoids" deficient in complement-firing activity were also deficient in chemotactic factor generation. Chemotactic factor could not be generated by endotoxin in sera of mice congenitally deficient in the C'S component of complement, while chemotactic factor was generated by endotoxin in the sera of coisogenic mice with normal complement levels for that species. The chemotactic factor induced by endotoxin was heat stable and nondialyzable. Molecular sieve chromatography and sucrose density gradient ultracentrifugation demonstrated that the chemotactic factor was a relatively low molecular weight product (15,000–30,000) and as such different from previously scribed C' system-derived chemotactic factors. These experiments demonstrate that generation of chemotactic factor by endotoxin in serum is dependent upon C' system activation involving at least C'5. Furthermore, the relatively low molecular weight of this factor suggests that it might be derived from activation of a single complement component rather than from complexing of multiple complement components

    Evaluation of the self-energy correction to the g-factor of S states in H-like ions

    Full text link
    A detailed description of the numerical procedure is presented for the evaluation of the one-loop self-energy correction to the gg-factor of an electron in the 1s1s and 2s2s states in H-like ions to all orders in ZαZ\alpha.Comment: Final version, December 30, 200

    Relativistic dynamical polarizability of hydrogen-like atoms

    Full text link
    Using the operator representation of the Dirac Coulomb Green function the analytical method in perturbation theory is employed in obtaining solutions of the Dirac equation for a hydrogen-like atom in a time-dependent electric field. The relativistic dynamical polarizability of hydrogen-like atoms is calculated and analysed.Comment: 15 pages, 3 figures (not included, but hard copies are available upon request

    Loop-after-loop contribution to the second-order Lamb shift in hydrogenlike low-Z atoms

    Get PDF
    We present a numerical evaluation of the loop-after-loop contribution to the second-order self-energy for the ground state of hydrogenlike atoms with low nuclear charge numbers Z. The calculation is carried out in the Fried-Yennie gauge and without an expansion in Z \alpha. Our calculation confirms the results of Mallampalli and Sapirstein and disagrees with the calculation by Goidenko and coworkers. A discrepancy between different calculations is investigated. An accurate fitting of the numerical results provides a detailed comparison with analytic calculations based on an expansion in the parameter Z \alpha. We confirm the analytic results of order \alpha^2 (Z\alpha)^5 but disagree with Karshenboim's calculation of the \alpha^2 (Z \alpha)^6 \ln^3(Z \alpha)^{-2} contribution.Comment: RevTex, 19 pages, 4 figure

    Phase Structure and Nonperturbative States in Three-Dimensional Adjoint Higgs Model

    Full text link
    The thermodynamics of 3d adjoint Higgs model is considered. We study the properties of the Polyakov loop correlators and the critical behavior at the deconfinement phase transition. Our main tool is a reduction to the 2d sine-Gordon model. The Polyakov loops appear to be connected with the soliton operators in it. The known exact results in the sine-Gordon theory allow us to study in detail the temperature dependence of the string tension, as well as to get some information about a nonperturbative dynamics in the confinement phase. We also consider the symmetry restoration at high temperature which makes it possible to construct the phase diagram of the model completely.Comment: 15pp., Revtex; 4 figures; replaced by a version to be published in Phys. Rev.

    Endoscopic transnasal transpterygopalatine fossa approach to the lateral recess of the sphenoid sinus

    Get PDF
    Q1Q1528-532Objectives Lesions affecting the lateral recess of the sphenoid sinus are rarely discussed in the literature as a separate entity. This region is difficult to visualize and manipulate through the transnasal routes, especially when extensive pneumatization is present. External approaches to this area involve extensive surgery and are associated with significant morbidity. The objectives of this study are to present our experience with the endoscopic transpterygopalatine fossa approach as a method for exposing and manipulating lesions of the lateral recess of the sphenoid and to illustrate the detailed surgical steps of the procedure. Study Design Retrospective review. Methods Clinical charts of patients who had lesions originating from or extending into the lateral recess of the sphenoid sinus and who were treated at our institutions from September 1995 to June 2002 were retrospectively reviewed. All these patients were managed by the endoscopic transpterygopalatine fossa approach. Results Twelve patients (7 males and 5 females) were included in the study. Lesions included seven cerebrospinal fluid (CSF) leaks and five tumors. One patient with squamous cell carcinoma (SCC) of the sphenoid died of his disease. All CSF leaks were successfully repaired, and benign tumors were removed with good local control through the follow‐up period. Conclusion The endoscopic transpterygopalatine fossa approach is an excellent approach for dealing with lesions of the sphenoid lateral recess

    Multibaryons as Symmetric Multiskyrmions

    Get PDF
    We study non-adiabatic corrections to multibaryon systems within the bound state approach to the SU(3) Skyrme model. We use approximate ansatze for the static background fields based on rational maps which have the same symmetries of the exact solutions. To determine the explicit form of the collective Hamiltonians and wave functions we only make use of these symmetries. Thus, the expressions obtained are also valid in the exact case. On the other hand, the inertia parameters and hyperfine splitting constants we calculate do depend on the detailed form of the ansatze and are, therefore, approximate. Using these values we compute the low lying spectra of multibaryons with B <= 9 and strangeness 0, -1 and -B. Finally, we show that the non-adiabatic corrections do not affect the stability of the tetralambda and heptalambda found in a previous work.Comment: 17 pages, RevTeX, no figure
    • 

    corecore