Comparing phenomenological recipes with a microscopic model for the electric amplitude in strangeness photoproduction

Corrections to the Born approximation in photo-induced strangeness production off a proton are calculated in a semi-realistic microscopic model. The vertex corrections and internal contributions to the amplitude of the $\gamma p \to K^+ \Lambda$ reaction are included on the one-loop level. Different gauge-invariant phenomenological prescriptions for the modification of the Born contribution via the introduction of form factors and contact terms are discussed. In particular, it is shown that the popular minimal-substitution method of Ohta corresponds to a special limit of the more realistic approach.Comment: 10 pages, 6 figures in the tex

Dynamics of 1S0^{1}S_0 diproton formation in the pd→{pp}snpd\to \{pp\}_sn and pN→{pp}sπpN\to \{pp\}_s\pi reactions in the GeV region

Mechanisms for the production of $^1S_0$ diproton pairs, ${pp}_s$, in the $pd\to {pp}_s n$ reaction are studied at proton beam energies 0.5 -- 2 GeV in kinematics similar to those of backward elastic $pd$ scattering. This reaction provides valuable information on the short-range $NN$ and $pd$ interactions that is complementary to that investigated in the well known $pd\to dp$ and $dp\to p(0^\circ)X$ processes. The $pd\to {pp}_sn$ reaction is related to the subprocesses $\pi^0 d\to pn$ and $pN\to {pp}_s \pi$ using two different one--pion--exchange (OPE) diagrams. Within both these models a reasonable agreement could be obtained with the data below 1GeV. The similar energy dependence of the $pd\to\{pp\}_s n$ and $pd\to dp$ cross sections and the small ratio of about 1.5% in the production of $\{pp\}_s$ to deuteron final states follow naturally within the OPE models.Comment: 10 pages, 7 figures, Late

Confirmation of taxonomic status of black yeast-like fungus by three gene phylogeny

Status of black melanin-containing yeast-like fungus Exophiala alcalophila isolated from microorganism complex of hermetic damaged in conditions of indoor high humidity in Kiev, Ukraine is proved by combined phylogenetic analysis based on sequences of the internal transcribed spacer 1 (ITS1), the 5.8S gene and the internal transcribed spacer 2 (ITS2) nrDNA, beta-tubulin gene and translation elongation factor 1-alpha gene. Sequences of the mentioned genes of Ukrainian specimen of E. alcalophila are for the first time submitted to the GenBank

A Possibility to Observe Short-Range NN Properties in the Deuteron Breakup pd→ppnpd\to ppn

Quasi-binary reaction of the deuteron breakup $p+d\to (pp)+n$ with the final proton-proton pair $(pp)$ in the $^1S_0$ state is analyzed at initial energies $0.5 - 2$ GeV in the kinematics of backward elastic pd-scattering $pd\to dp$. On the basis of the main mechanisms of the $pd\to dp$ process, including initial and final state interaction, we show that unpolarized cross section and spin observables of this reaction exhibit important properties of the half-off-shell $pp(^1S_0)$-scattering amplitude, which are relevant to the nucleon-nucleon interaction at short distances.Comment: 9 pages, Latex, 3 Postscript figure

Compton scattering on the nucleon at intermediate energies and polarizabilities in a microscopic model

A microscopic calculation of Compton scattering on the nucleon is presented which encompasses the lowest energies -- yielding nucleon polarizabilities -- and extends to energies of the order of 600 MeV. We have used the covariant "Dressed K-Matrix Model" obeying the symmetry properties which are appropriate in the different energy regimes. In particular, crossing symmetry, gauge invariance and unitarity are satisfied. The extent of violation of analyticity (causality) is used as an expansion parameter.Comment: 35 pages, 15 figures, using REVTeX. Modified version to be published in Phys. Rev. C, more extensive comparison with data for Compton scattering, all results unchange

Rotational covariance and light-front current matrix elements

Light-front current matrix elements for elastic scattering from hadrons with spin~1 or greater must satisfy a nontrivial constraint associated with the requirement of rotational covariance for the current operator. Using a model $\rho$ meson as a prototype for hadronic quark models, this constraint and its implications are studied at both low and high momentum transfers. In the kinematic region appropriate for asymptotic QCD, helicity rules, together with the rotational covariance condition, yield an additional relation between the light-front current matrix elements.Comment: 16 pages, [no number

СТАН МІКРОБІОЦЕНОЗУ НИЖНІХ СТАТЕВИХ ШЛЯХІВ ТА ЗАХОДИ ЙОГО КОРЕКЦІЇ У ЖІНОК З ПОЗАМАТКОВОЮ ВАГІТНІСТЮ.

The article presents some information on therapeutic approaches to the management of women with an ectopic pregnancy before, during and after surgery, to improve the efficiency of recovery microbiocenosis lower genital tract that can contribute to improving in general reproductive health of this group of patients.В статье представлена информация про особенности ведения женщин с внематочной беременностью до, во время и после оперативного лечения для повышения эффективности восстановления микробиоценоза нижних отделов половых путей, что в последующем может способствовать улучшению репродуктивного здоровья этой группы пациентов. У статті представлена інформація про особливості ведення жінок з позаматковою вагітністю до, під час і після оперативного лікування для підвищення ефективності відновлення мікробіоценозу нижніх відділів статевих шляхів, що в подальшому може сприяти поліпшенню репродуктивного здоров'я цієї групи пацієнтів