Periodic solutions of massive φ 4 and Yang-Mills theories

The well-known connection between the SU(2) gauge theory and the massless ⁴ theory is extended to theories with nonzero mass. Elliptic solutions of these massive theories are given. These are of the plane-wave variety, with independent variable u=p·x where p is a constant four-vector. They depend on a free parameter k. Two of the solutions are generalized plane-waves while the third describes fluctuations about the vacuum solution.     

Cytokine mRNA expression and serum cortisol evaluation during murine lung inflammation induced by Mycobacterium tuberculosis

A model system was characterized for investigating the potential role of cortisol in MTB induced immunopathology. Serum cortisol levels were evaluated in two mouse strains; C57BL/6 mice develop lung granulomas following acute Mycobacterium tuberculosis infection while A/J mice are deficient in this process. Serum cortisol levels were examined post infection, as well as immunoregulatory mRNA expression in the lung, measured using bioluminescent RT-PCR techniques. Prior to infection, the A/J mice constitutively maintain nearly 75&percent; higher serum cortisol than C57BL/6 mice. Both A/J and C57BL/6 mice exhibited approximately 30&percent; reduction in relative serum cortisol following infection. At no time did serum cortisol levels in the A/J fall below constitutive levels in the non-infected C57BL/6. The overall elevated cortisol in the A/J may affect pulmonary immunoresponsiveness; A/J mice exhibited earlier induction of IL-10 and TNF-alpha than C57BL/6 mice, with a relative lack of IL-2 during late infection. Conversely, the C57BL/6 mice demonstrated higher IL-12(p40) and IL-2 messages at the latter stages of disease than the A/J mice. Both mice demonstrated high IFN-&gama; mRNA. The high constitutive serum cortisol in the A/J mice may therefore contribute to establishment of an environment counter-productive to initiation of protective Th1 cell and granulomatous responses.     

Effects of lipopolysaccharide-induced inflammation on expression of growth-associated genes by corticospinal neurons

Background  

Inflammation around cell bodies of primary sensory neurons and retinal ganglion cells enhances expression of neuronal growth-associated genes and stimulates axonal regeneration. We have asked if inflammation would have similar effects on corticospinal neurons, which normally show little response to spinal cord injury. Lipopolysaccharide (LPS) was applied onto the pial surface of the motor cortex of adult rats with or without concomitant injury of the corticospinal tract at C4. Inflammation around corticospinal tract cell bodies in the motor cortex was assessed by immunohistochemistry for OX42 (a microglia and macrophage marker). Expression of growth-associated genes c-jun, ATF3, SCG10 and GAP-43 was investigated by immunohistochemistry or in situ hybridisation.     

Meronlike solutions of nonlinear spinor theories

Properties of meronlike solutions of nonlinear spinor theories are discussed — in particular, their relationship with static pointlike Minkowski solutions of the same theory.     

Meron-antimeron solution in Minkowski space

An elementary derivation, using Witten's Ansatz, is given of the elliptic meron-antimeron solution of the (Minkowski) SU(2) gauge theory in the W ₀=0 gauge.     

Zeta Function Resummation of Spectral Functions

This article continues an extensive analysis of spectral functions such as for both general and explicitly known spectra {λ_m}. In physical applications (which in quantum field theory are numerous) the spectral functions are mode sums. Our main analytic tool is the ζ-function resummation method which expresses f(s|x) in powers of x and perhaps other simple functions of x. Here the general spectrum will be replaced by its asymptotic form λ_m = (const) m^α with α > 0 (Weyl's theorem). This preserves certain global features of the general spectrum problem but enables one to work entirely in terms of known functions. This simplified problem will be fully analysed and certain aspects of it (in particular the continuum limit) studied for the first time. Several mode-sum calculations illustrate physical application of the method.     

Self dual solutions of the temperature SU(2) Yang-Mills theory

Continuing previous work we elaborate on the method of “heating” the self-dual axially symmetric fields of the SU(2) Yang-Mills theory to finite temperature. Heating consists of performing—in certain Ansatz functions which are two-dimensional (2D) conformally invariant—a 2D conformal transformation x = x₀ + i ∥x∥ → y(x), where the analytic function y(x) is periodic in the Euclidean time variable x₀. Solutions are preserved by this manipulation, which automatically changes zero-temperature fields into finite temperature ones. One can exploit this simple fact in various ways. The Harrington-Shepard caloron solution of the temperature Yang-Mills theory can be gotten from the T = 0 instanton by the transformation y(x) = (πT)^?1 tan πTx. One can generate a multicaloron solution from the T = 0 one instanton solution by a conformal transformation. Generally, self-dual axially symmetric Yang-Mills fields can be heated without spoiling self duality. The caloron and three other temperature solutions are studied in some detail. One of the new solutions is a generalized caloron with interesting properties. Our study reveals a remarkable property of the self-dual sector of the temperature Yang-Mills theory: it is full of Wu-Yang (color) monopoles at high temperature. At low temperature these monopoles disappear.     

Characteristics of double-pomeron exchange

A detailed kinematic study is made of the cross section for double-pomeron exchange. We consider reactions of the type a + b → c + d + (h₁ + h₂ + …) where a → c and b → d are quasi-elastic transitions with limited momentum transfer and (h₁ + h₂ + …) is a centrally produced hadron cluster. The dependence of the cross section on the relative azimuthal angle φ between the final hadrons c and d provides an important test for double-pomeron exchange. We calculate this φ-dependence for all cases of interest, using a model in which pomeron exchange is represented by an effective current-current interaction. For limited momentum transfer, where the pomeron spin is nearly equal to one, this model is equivalent to Reggeized pomeron exchange. We give a complete formalism for the partial-wave analysis of the double-pomeron reaction ab → cd + h₁₂ which differs from the one given by Rushbrooke and Webber. Furthermore, we discuss the two-pomeron vertex, and the construction of detailed and realistic models for double-pomeron reactions.     

Beta-delayed proton emitter kr

The nucleide ⁷³Kr has been identified by on-line mass separation as a precursor of β-delayed proton emission. The proton branch is (6.8 ±1.2) × 10⁻³ proton/decay. The protons populate the ground state and also the first excited 2⁺ state at 866 keV in ⁷²Se with a relative intensity of (35±9) %. The value of Q_EC−B_p, where B_p is the proton separation energy for the nucleus ⁷³Br, is found to be 4.85 ±0.30 MeV based on the fraction of proton events preceded by positron decay.     

Zeta-function derivation of Euler-MacLaurin sum rules

The Euler-MacLaurin summation formula and other sum rules of the same type are derived by the -function method for infinite series.