[en] The annihilation cross-section of ultralow-energy atomic antihydrogen (E≤10^-5 a.u.) on atomic hydrogen is calculated within a quantum mechanical coupled channels approach. The results differ from the extrapolations of semiclassical models to low energies. The main features of the observables are found to be determined by a family of HH-bar near-threshold metastable states. We show that the presence of such states results in a strong enhancement of nuclear effects in HH-bar scattering, strong isotope effect in DH-bar scattering, oscillatory behavior of the cross-sections as function of the van der Waals constant C₆, thought of as a free parameter

[en] The cross section for the annihilation of ultraslow antiprotons (with energies on the order or less than 10^-4 eV) with atomic hydrogen is calculated. Effects which are nonadiabatic with respect to the relative motion of the heavy particles are taken into account. The inverse Auger process (Pr + e → H + bar p) is also taken into account. The annihilation probability is found to be smaller by a factor of 10 or more than the values which have been calculated previously in the adiabatic approximation and under the assumption of a one-time production of protonium. 13 refs., 2 figs

[en] With involving the nonadiabatic effects with respect to the relative motion of heavy particles and the back-Auger process (Pr+e->H⁺p) the atomic hydrogen - ultraslow antiprotons annihilation cross-section with the energy about and smaller 10^-4 eV is calculated. The annihilation probability is shown to be ten and more times less than the values obtained before in the calculations based on the adiabatic approximation and on assumption about the single formation of a protonium

[en] We show that attractive singular potentials -α_sIr^s, s ≥ 2, can be regularized by an infinitesimal imaginary addition to the interaction strength α_s = Re α_s±iO. Such a procedure enables the unique definition of the scattering observables and is equal to an absorption (creation) of the particles in the origin. We discuss the physical sense of such a regularization as well as a possible application of the developed formalism to the systems with a short-range annihilation. (author)

[en] We discuss the relation between attractive singular potentials -α_s/r^s, s≥2, and inelasticity. We show that attractive singular potentials can be regularized by an infinitesimal imaginary addition to the interaction strength α_s=Reα_s±i0. Such a procedure enables the unique definition of the scattering observables and is equal to an absorption (creation) of the particles in the origin. It is shown that the suggested regularization is an analytical continuation of the scattering amplitudes of a repulsive singular potential as a function of the interaction strength α_s. Thus a regularized singular potential has no bound states. The near-threshold properties of the regularized singular potential are examined. We obtain expressions for the scattering lengths, which turn to be complex even for an infinitesimal imaginary part of the interaction strength. The problem of the perturbation of the near-threshold spectrum of a regular potential by a singular one is treated, the expressions for the level shifts and widths are obtained. The physical sense of the suggested regularization is that the scattering observables are insensitive to any details of the short-range modification of a singular potential if there exists sufficiently strong inelastic short-range interaction. In this case, the scattering observables are determined by the solutions of the Schroedinger equation with the regularized potential -(α_s±i0)/r^s. Possible applications of the developed formalism to the systems with a short-range annihilation are discussed

[en] This paper studies changes in the ingestive capacity of resident macrophages (M) from different organs of the reticuloendothelial system (RES) after a single pharmacologic dose of hydrocortisone (HC) was injected into female rats. In a second series of experiments, mice were given an intravenous injection of 10⁸ sheep's red blood cells (SRBC), labeled with Cr 51 (Cr 51-SRBC) 2, 24, and 72 h after injection of 125 mg/kg of HC. Results indicate that the sensitivity of resident M from different organs to HC differs. It may be possible to modify singificantly hormone-dependent metabolic changes in different versions of acute stress and in the course of long-term adaptation, through modulation of reacitivity of Kupffer cells and of the RES as a whole

No abstract available

[en] Complete text of publication follows. The new devices have been developed for laser beams homogenizing in the focal spot - multi-component lens raster and raster with the edges smoothing phase mask. The envelope non-uniformity of < 3-5% at energy concentration up to 60% was achieved for beams having the initial non-uniformity in the near field of approximately 30% and divergence ≤ 10^-4 radians. Investigation into the temporary-spatial smoothing with the use of low-density foams with the density less than the critical one is still in progress. Experiments on the foams with the density of 1-2.3 mg/cm³, thickness of 100-200 μm, and the cells' sizes up to the tens of micrometers were carried out with the radiation wavelength of 0.657 μm. The RMS non-uniformity < 5% has been found for the beam passed through the foam. The non-uniformity is evenly distributed over the spatial frequency spectrum. The induced divergence of radiation is measured to be 0.35 radian. The frequency of the rearranged speckled field of about 2 THz was obtained. The beam smoothing was recorded from the start of pulse of radiation, had the duration up to 1 ns, and the width of the radiation spectrum was about 30 A. The work was performed in part under the sponsorship of the RFFI (grants No. 09-02-12157-ofi-m and No. 09-02-97095-r-povolzh'ye-a) and grant of the President of the RF to leading scientific schools No. 65192.2010.2.

[en] Hadron electromagnetic form factor in the time-like region at the boundary of the physical region is considered. The energy behavior of the form factor is shown to be determined by the strong hadron-antihadron interaction. We propose a simple phenomenological model of the hh-bar interaction that describes the form factor behaviour in the region where scattering length approximation fails and estimate on its basis imaginary part of the scattering lengths (volumes) for ΛΛ-bar, ΛΣ-bar⁰(Λ-barΣ⁰), Σ⁰Σ-bar⁰ and D*D*-bar from present experimental data. The developed approach enables us to analyze the existence of baryon-antibaryon (BB-bar) near threshold resonances. The experiments to extract detailed information on the near threshold BB-bar interaction from hadron form factor energy behavior are suggested.

[en] Recent experimental studies of the antiproton-deuteron system at low energies have shown that the imaginary part of the antiproton-deuteron scattering length is smaller than the antiproton-proton one. Two- and three-body systems with strong annihilation are investigated and a mechanism explaining this unexpected relation between the imaginary parts of the scattering lengths is proposed. (orig.)