AC loss in a stack of flat superconducting cables

An equation has been derived which describes the current distribution in a flat cable subjected to a time-dependent magnetic field directed perpendicular to the cable wide face. Solutions of this equation obtained in the case when all parameters are uniform along the cable allow us to obtain the time constant spectrum, magnetic moment of the cable and A.C. loss. For a stack of cables with height much larger than the cable width, the contribution of the self-screening is calculated analytically. Numerical examples are provided based on geometrical characteristics and interstrand contact resistance of a typical LHC cable and the inductance of the LHC dipole

TOPOLOGICAL OBJECTS AND CONFINEMENT ON THE LATTICE

First we discuss various topological objects (monopoles, ``minopoles'' and ``hybrids'') which may be important for the confinement mechanism in various abelian projections. The second topic is the string between quark and antiquark. The standard quantum string with the Nambu-Goto action exists only in D=26. If we start from the field theory, in which the string excitations exist, and change the variables in the path integral to the string variables, then the Jacobian appears. This Jacobian generates the correction to the Nambu-Goto action. For this effective action the conformal anomaly cancels in D=4. Thus we get the quantum string theory in D=4.Comment: 9 pages, LaTeX, 2 uuencoded tar-compressed postscript figures, needs psfig.tex; talk given by Polikarpov M.I. at International RCNP Workshop on Color Confinement and Hadrons (Confinement 95), March 22--24, 1995, RCNP, Osaka, Japan. (Revision: problems in figures fixed

Beta decay and other processes in strong electromagnetic fields

We consider effects of the fields of strong electromagnetic waves on various characteristics of quantum processes. After a qualitative discussion of the effects of external fields on the energy spectra and angular distributions of the final-state particles as well as on the total probabilities of the processes (such as decay rates and total cross sections), we present a simple method of calculating the total probabilities of processes with production of non-relativistic charged particles. Using nuclear beta-decay as an example, we study the weak and strong field limits, as well as the field-induced beta-decay of nuclei stable in the absence of the external fields, both in the tunneling and multi-photon regimes. We also consider the possibility of accelerating forbidden nuclear beta-decays by lifting the forbiddeness due to the interaction of the parent or daughter nuclei with the field of a strong electromagnetic wave. It is shown that for currently attainable electromagnetic fields all effects on total beta-decay rates are unobservably small.Comment: LaTeX, 30 pages, 2 figures. Invited contribution to the special issue of Yadernaya Fizika dedicated to the centennial anniversary of birthday of A.B. Migdal. V2: references adde

Chizhov and Petcov Reply

We have found in [1] new conditions for a total neutrino conversion in the case of neutrino oscillations taking place in a medium, consisting of n = 2 (or 3) alternating layers with constant densities $N_1$ and $N_2$. It is claimed in [4] that our results are particular case of enhancement of neutrino oscillations, which was suggested earlier by other authors and was widely discussed in the literature. We refute these claims, confirming the novelty of our results.Comment: 2 pages, LATEX; concise (essentially 1 page) and somewhat modified version of Ref. SISSA 5/2000/EP (hep-ph/0003110); reply on the ``Comment on New Conditions for a Total Neutrino Conversion in a Medium'', Phys. Rev. Lett. 85 (2000) 3978; published as ``Chizhov and Petcov Reply'' in Phys. Rev. Lett. 85 (2000) 397

Floquet theory of neutrino oscillations in the earth

We review the Floquet theory of linear differential equations with periodic coefficients and discuss its applications to neutrino oscillations in matter of periodically varying density. In particular, we consider parametric resonance in neutrino oscillations which can occur in such media, and discuss implications for oscillations of neutrinos traversing the earth and passing through the earth's core.Comment: LaTeX, 28 pages, 8 eps figures. Contribution to the special issue of Yad. Fiz. dedicated to the memory of A.B. Migda

Exotic smooth structures on 4-manifolds with zero signature

For every integer $k\geq 2$, we construct infinite families of mutually nondiffeomorphic irreducible smooth structures on the topological $4$-manifolds $(2k-1)(S^2\times S^2)$ and (2k-1)(\CP#\CPb), the connected sums of $2k-1$ copies of $S^2\times S^2$ and \CP#\CPb.Comment: 6 page

Experience in The Use of Antibiotics in The Treatment of Abscess Phlegmon of The Maxillofacial Area in Children

Acute odontogenic inflammatory diseases in the maxillofacial region, affecting 55-65% of cases, present a pressing issue in surgical dentistry. Despite extensive research, treatment outcomes remain suboptimal, with environmental factors and microbial etiology contributing to the challenge. A study from 2021 to 2023 examined 55 pediatric patients hospitalized for these conditions, emphasizing early diagnosis and surgical interventions. The addition of Abasit syrup to traditional treatments showcased promising results. The research underscores the need for meticulous surgical procedures and innovative therapeutic approaches. &nbsp

De Sitter space and perpetuum mobile

We give general arguments that any interacting non--conformal {\it classical} field theory in de Sitter space leads to the possibility of constructing a perpetuum mobile. The arguments are based on the observation that massive free falling particles can radiate other massive particles on the classical level as seen by the free falling observer. The intensity of the radiation process is non-zero even for particles with any finite mass, i.e. with a wavelength which is within the causal domain. Hence, we conclude that either de Sitter space can not exist eternally or that one can build a perpetuum mobile.Comment: 11 pages revtex, no figures. Added discussion to strengthen conclusio