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Aquaculture provides the population with high-quality food products containing a number of valuable vitamins, minerals and omega acids. Breeding fish in artificial conditions is difficult without creating new and productive fish breeds. The species of rainbow trout turned out to be in steady demand in the market. The Rostal breed, originated from the SGC “Ropsha” through individual and family breeding, is highly adaptable and productive in cold-water conditions. The aim of the work was to identify the features of the genetic structure of various groups of rainbow trout of the Rostal breed by multilocus analysis using a digoxygenin-labeled DNA probe (GGAT)4. Using methods to simultaneously detect multiple polymorphisms increases the analysis throughput. Modern computer programs based on the distribution of DNA fragments calculate population genetic parameters. Earlier, we carried out work on rainbow trout with revealing the features of genetic organization at the level of populations of different breeds. In the framework of this study, the characteristics of individual groups of trout from various basins and having a different origin were revealed. It was established that individual groups have marker DNA fragments that distinguish them from other groups. The maximum genetic divergence was found between group A and group C, group B and group D. The groups A and B, B and C were moderately distant from each other. The groups D and C, A and D turned out to be closest in our study. The data helps breeders to take a scientifically sound approach to the breeding process by selecting individuals or groups of individuals with known genetic characteristics. Studies have shown that with long-term breeding of the group by family, a decrease in heterozygosity is observed, however, with the transition to mass selection, genetic diversity increases.

In the article the comparative analysis was done on the ontogeny of three genotypes of Ropsha carp having different origin and their phenotypic features, at different ages. This fish species is not well adapted to North-Western regions of the country that is why breeding work aimed at generation of new breeding forms suitable for aquaculture is of great importance. Biometric processing of primary accounting data was performed. Indicators of live weight, measurements, calculated ratios length, thickness, fatness were analyzed. The high variability of ontogenesis in yearlings was identified. Over time the second and third years of the three genotypes became more balanced. Individuals of return genotype in the third year have a maximum live weight. Representatives of BB cuttings in the first year of life were much superior to individuals of other strains in growth, size, but in the future their growth is slowing down. It is known that genotype BB was generated by crossing with another variety of carp, the fact that might explain accelerated growth of this fish. Cuttings from reciprocating interlined in the first year of life showed minimal results, in the future, the pace of growth increases, and in the third year of life, they did not stand out much in size and weight. The genetic characteristics of the representatives of the BB cuttings obviously affect the increase in body mass when compared with other genotypes. The VM layering (reciprocal-interlinear) in the first year of life shows minimal results, in the future the growth rate increases, and in the third year of life they are not very distinguished by size and weight.

A new specialized MPD Test Beam setup was mounted at the extracted beam of the Nuclotron at the Joint Institute for Nuclear Research to carry out methodical research and test detectors produced for the MPD experiment at the NICA accelerating facility. The setup is described in detail. The results of the testing of fast detectors for the MPD time-of-flight system are presented as an example of the operation of the setup.

The Multi-Purpose Detector (MPD) is designed to study a hot and dense baryonic matter formed in heavy-ion collisions at SQRT(sNN)=4-11 GeV at the NICA accelerator complex (Dubna, Russia). Large-sized electromagnetic calorimeter (ECal) of the MPD spectrometer will provide precise spatial and energy measurements for photons and electrons in the central pseudorapidity region of |eta

The analyzing powers for neutron charge exchange nA → pX reactions on nuclei have been measured on C, CH2 and Cu targets at incident neutron momenta 3.0 - 4.2 GeV/c by detecting one charged particle in forward direction. The polarized neutron measurements are the first of their kind. The experiment was performed using the Nuclotron accelerator in JINR Dubna, where polarized neutrons and protons were obtained from breakup of a polarized deuteron beam which has a maximum momentum of 13 GeV/c. The polarimeter ALPOM2 was used to obtain the analyzing power dependence on the transverse momentum of the final-state nucleon. These data have been used to estimate the figure of merit of a proposed experiment at Jefferson Laboratory to measure the recoiling neutron polarization in the quasi-elastic 2 H(e, e′n) reaction, which yields information on the charge and magnetic elastic form factors of the neutron.

The large barrel-shaped, shashlyk-type electromagnetic calorimeter (ECal) is an important part of the Multi-Purpose Detector (MPD) of the heavy-ion NICA experiment, and is designed to provide spatial and energy measurements for photons and electrons in the energy range from 40 MeV to 2–3 GeV. To deal with the high multiplicity, the ECal is finely segmented and made up of 38,400 cells (‘towers’) which are grouped into modules of 16 ‘towers’ each. ECal projective geometry of the ‘towers’ oriented towards the beam interaction zone results in 8 different types of modules depending on their position in the ECal. As beam calibration of each individual ‘tower’ is time and resource expensive, we discuss our strategy of calibration for the ECal modules with cosmic muons and present some preliminary results.

International audience; During two beam runs in the years 2016 and 2017, the analyzing powers (Ay) for protons and neutrons scattering on CH2, CH, C and Cu targets were measured at the nucleon momentum from 3.0 to 4.2 GeV/c with the ALPOM2 setup at the Nuclotron accelerator. The data for polarized neutron beam are obtained for the first time, thanks to the unique polarized deuteron beam that is presently available up to 13 GeV/c. Earlier, analyzing powers for polarized neutrons had been measured only for thin hydrogen targets. Cross sections and analyzing powers for np, for both elastic scattering and charge exchange are known up to 29 GeV/c. No data existed for thick analyzers. The measurement of the angular dependence of Ay for the neutron is essential to the continuation of the neutron form factor measurements to the highest possible transferred momentum-Q2 at the Jefferson Laboratory. The reaction p+Cu(W), with the detection of a neutron in the forward direction by a hadron calorimeter, can be used for the measurement of the proton polarization at the future NICA collider.

A Multi Purpose Detector (MPD) is being constructed for the Heavy-Ion Collider at Dubna (NICA). One of the important components of MPD setup is an Electromagnetic Calorimeter, which will operate in the magnetic field of MPD solenoid 0.5 T and provide good energy and space resolution to detect particles in the energy range from ~20 MeV to few GeV . For this purpose the, so-called, "shashlyk" sampling structure with the fiber readout to the silicon Multi Pixel Avalanche Photodetector is used. Serious modifications in comparison to conventional "shaslyk" calorimeter are proposed to improve the properties of device. These modifications are presented in the report along with the beam test results obtained with the MPD/NICA module prototypes.

Study of 17 single nucleotide polymorphisms has been performed to determine the factors of genetic predisposition to essential hypertension. Polymerase chain reaction (PCR) with subsequent analysis of restriction fragment length, allele specific PCR or real-time PCR was used for genotyping of 17 single nucleotide polymorphisms in 14 genes in 145 children with essential hypertension and 144 healthy persons with following complex multivariate statistical analysis. Two single nucleotide polymorphisms--MMP9 (C(-1562) --T) and NOS3 (Glu298 --Asp)--rs3918242 and rs1799983--were shown to represent the main independent effects with the highest predictive potential (77.1% as indicated by binary logistic regression and 74.6% testing accuracy shown by Multifactorial Dimensionality Reduction). MMP9 (C(-1562 --T) and NOS3 (Glu298 --Asp) potentially may be used to create predictive algorithm for determination of predisposition to arterial hypertension in children.

The Multipurpose Detector (MPD) \cite{cite1.MPD_CDR} is designed to study of hot and dense baryonic matter in collisions of heavy ions over the atomic mass range 1--197 at the centre of mass energy up to $\sqrt{S_{NN}}$ = 11 GeV (for Au79+). The MPD experiment will be carried out at the JINR accelerator complex NICA \cite{cite2.NICA_CDR} which is under construction. The barrel part of the MPD consists of various detectors surrounding the interaction point. It includes a precise tracking system (time projection chamber (TPC) and silicon inner tracker (IT)) and high-performance particle identification system based on time-of-flight (TOF) and calorimeter (ECal). The triple-stack multigap resistive plate chamber is chosen as an active element of the TOF. It provides good time resolution and long term stability. This article presents parameters of the MRPC obtained using the deuteron beam of JINR accelerator Nuclotron. The time resolution is $\sim$40 ps with efficiency of 99\%. Rate capability studies resulted with a time resolution of 60 ps and efficiency higher than 90\% on the beam with particle flux densities up to 2 kHz/cm$^2$., 8 pages, 10 figures, Proceedings of the XIII Workshop on Resistive Plate Chambers and Related Detectors (RPC2016), February 22 - 26, 2016, Ghent, Belgium