Decline of unique Pontocaspian biodiversity in the Black Sea Basin: a review

Environmental Biolog

Complete measurement of three-body photodisintegration of 3He for photon energies between 0.35 and 1.55 GeV

The three-body photodisintegration of 3He has been measured with the CLAS detector at Jefferson Lab, using tagged photons of energies between 0.35 GeV and 1.55 GeV. The large acceptance of the spectrometer allowed us for the first time to cover a wide momentum and angular range for the two outgoing protons. Three kinematic regions dominated by either two- or three-body contributions have been distinguished and analyzed. The measured cross sections have been compared with results of a theoretical model, which, in certain kinematic ranges, have been found to be in reasonable agreement with the data.Comment: 22 pages, 25 eps figures, 2 tables, submitted to PRC. Modifications: removed 2 figures, improvements on others, a few minor modifications to the tex

Beam Spin Asymmetries in DVCS with CLAS at 4 .8 GeV

We report measurements of the beam spin asymmetry in Deeply Virtual Compton Scattering (DVCS) at an electron beam energy of 4.8 GeV using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The DVCS beam spin asymmetry has been measured in a wide range of kinematics, 1(GeV/c)$^2$ $<Q^2<2.8$(GeV/c)$^2$, $0.12<x_B<0.48$, and 0.1 (GeV/c)$^2$ $<-t<0.8$(GeV/c)$^2$, using the reaction \pEpX. The number of H$(e,e^{\prime}\gamma p)$ and H$(e,e^{\prime}\pi^0 p)$ events are separated in each $(Q^2,x_B,t)$ bin by a fit to the line shape of the H$(e,e^{\prime}p)X$ $M_x^2$ distribution. The validity of the method was studied in detail using experimental and simulated data. It was shown, that with the achieved missing mass squared resolution and the available statistics, the separation of DVCS-BH and $\pi^0$ events can reliably be done with less than 5% uncertainty. The $Q^2$- and $t$-dependences of the $\sin\phi$ moments of the asymmetry are extracted and compared with theoretical calculations

Infestation of

In this study we analyzed comparatively the host-parasite associations between two fish host species invasive in Europe (Lepomis gibbosus and Pseudorasbora parva) and one known generalist parasite species, the copepod Lernaea cyprinacea. We used a fragment of the hypervariable region D1-D2 of the 28S rRNA to confirm that the copepod specimens collected on both host species in our study are indeed conspecific. The prevalence of infection was significantly different between the two host species in all three aquatic ecosystems. Two populations of L. gibbosus exhibited a positive correlation coefficient between the standard body length and infection intensity, while a negative correlation coefficient was observed in one population of P. parva. This is one of the few studies providing parasitological parameters of infections of Lernaea cypriancea in Lepomis gibbosus and Pseudorasbora parva

Cross-amplification of microsatellite loci in the endangered stone-crayfish Austropotamobius torrentium (Crustacea: Decapoda)

The major aim of this study is to describe the first microsatellite loci for the stone-crayfish (Austropotamobius torrentium), by cross-species amplification. Austropotamobius torrentium is a priority species in the EU Habitats Directive and it needs effective conservation management efforts throughout Europe. We tested cross-species amplification of 55 decapod microsatellite primer pairs in A. torrentium and only ten of these loci, from relatively close related species, yielded PCR products of expected sizes. Five of the ten microsatellites proved to be polymorphic (allele numbers ranging from 4 to 14 in a set of 35 individuals). Three of the loci exhibited departure from Hardy-Weinberg equilibrium which could be explained by the presence of null alleles. A forth locus exhibiting HWE deviation, but no null alleles, suggest the possible presence of population substructure of the species in the investigated area. These microsatellite markers are useful for population genetic studies of stone-crayfish

Electroexcitation of the Roper resonance for 1.7

The helicity amplitudes of the electroexcitation of the Roper resonance are extracted for 1.