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A huge amount of experimental data should be collected, stored and processed in large modern high-energy physics experiments, including the experiments of the NICA (Nuclotron-based Ion Collider fAcility) project at the Joint Institute for Nuclear Research. In this regard, corresponding performance requirements are put forward for existing online systems. The online data processing system developed for the BM@N experiment within the NICA project is based on a distributed architecture, enabling it to meet high performance requirements through scalability and parallel computing. The purpose of the online system is selective data processing (conversion to event digits in the CERN ROOT format and fast event reconstruction) and data monitoring of the ongoing experiment. To achieve this goal, the FairMQ package implemented by the FAIR collaboration (GSI Institute, Germany) has been chosen to communicate distributed processes executed on the nodes of the computing infrastructure with each other through the exchange of their messages. One of the issues in developing and using such systems is the problem of the distributed run and control of the processes. The task has been solved by using the FAIR DDS (Dynamic Deployment System) toolkit. The BM@N online system starts the predefined software tasks in a required sequence and allows managing them during sessions, including the transmission of messages between the tasks and the update of some properties. The paper presents the purposes and architecture of the Online Data Processing System for the BM@N experiment and features of the current implementation. [ABSTRACT FROM AUTHOR]

The paper reports data on the age and composition of poorly studied Cretaceous clastic rocks of the Lower Amur River area, which are part of the Zhuravlevka–Amur terrane and are attributed to the Berriasian–Valanginian Komsomolsk series. U/Pb dating of detrital zircons yielded reliable dates of 99 and 90 Ma for the Gorin and Pioneer formations, respectively. Thus, a sedimentary complex with a Late Cretaceous sedimentation age was identified for the first time in the Sikhote-Alin orogenic belt based on detrital zircon geochronology. In composition and detrital zircon age distribution pattern, the studied rocks are more similar to sediments of the upper, Hauterivian–Albian part of the Zhuravlevka–Amur terrane section rather than to those of the lower, Berriasian–Valanginian part. In rocks of the Pioneer Formation, the youngest zircon population with an age of about 90 Ma makes up more than 40% of all dated grains. The main source of detrital material of this age was probably proximal andesites hosting the Mnogovershinnoe deposit and granitoids of the Nizhneamurskii Complex. The source of detritus for sediments of the ∼99 Ma Gorin Formation was probably felsic rocks from the Albian–Cenomanian igneous province of Pacific Asia. The discrepancy between the Late Cretaceous age obtained by us and the paleontologically established Berriasian–Valanginian stratigraphic age of the formations requires additional research. New data on the Late Cretaceous age of the Zhuravlevka–Amur sediments of strike-slip marginal-continental basin requires revision of the geologic evolution of the terrane and the entire Sikhote-Alin orogenic belt. [ABSTRACT FROM AUTHOR]

The Komsomolsk tin-ore district is located along the Miao-Chan Ridge in the Middle Amur River area (Khabarovsk krai) within the Badzhal accretionary terrane of the Sikhote-Alin orogenic belt. This work presents new results of U–Pb zircon dating of tonalite from the Miao-Chan complex of the Silinka granite pluton (99.7 ± 1.1 Ma) and rhyolites of the lower part of the Kholdami Formation (98.4 ± 1.0 and 98.7 ± 1.2 Ma) from the northeastern part of the Komsomolsk district. The geochemical characteristics of the rocks studied show that granitoids of the Miao-Chan complex are I-type rocks and that synchronous rhyolites of the Kholdami Formation are highly aluminous and correspond to S-type rocks. New data on the composition and early Cenomanian age of the rocks make it possible to consider the ore-magmatic system of the Komsomolsk ore district as part of the previously identified Albian–Cenomanian igneous province of Pacific Asia. [ABSTRACT FROM AUTHOR]

The results of large-scale radiation, genetic, cytogenetic, and molecular genetic studies on the nature and frequency of heritable mutations of two sex-linked and three autosomal genes of Drosophila melanogaster after exposure to 60Co γ-rays and 0.85 MeV neutrons are presented. Regularities were established for the studied genes and radiations in the induction of five different types of recessively inherited mutations, which can be combined into two main classes—the class of chromosomal mutations in one way or another affecting the gene under study (changes leading to sterility of F1 mutants, multilocus deletions, inversion or translocation breakpoint chromosome in the region of gene localization) and a class of "point" gene mutations with a complex spectrum of DNA changes detected by PCR and sequencing. In this report, the results of classical genetic and cytogenetic analysis of these classes of mutations are considered in detail and the frequency of their induction by γ-rays or neutrons is estimated per locus per dose unit (1 Gy). An important and unexpected result of the assessment was the fact that the frequency of "point" mutations turned out to be invariant (on average, 1.15 E-06/locus/Gy) for the studied genes and radiation, in contrast to chromosomal mutations, where a pronounced locus-specificity is observed for individual types of mutations. At the same time, neutrons are two or more times more effective than γ-rays in inducing this class of mutations. It is significant that the average frequency of "point" mutations induction correlates with the average cDNA length of these genes (1.62 kb), but not with their average size (6.07 kb), indicating that the target for "point" mutations is, obviously, not the entire DNA of the gene, but only the informational part of its exons. The dependence of the frequency of chromosomal mutations of one type or another on the position of the gene on the chromosome and in the three-dimensional space of the genome is discussed. [ABSTRACT FROM AUTHOR]

A mathematical model is presented that provides a description of electromagnetic processes in the "network–load–active power filter" system. In particular, by specifying the shape of the load-current and the network-voltage parameters, it is possible to determine the quality indicators of electric power at the common connection point: the quality indicators of the network voltage and currents in network and load sections. The model also makes it possible to calculate the instantaneous values of currents in the power circuit of the most active filter, thus enabling the power loss in the filter to be estimated. The mathematical model is based on the spectral method of analysis of periodic nonsinusoidal processes and the use of switching functions. It is a feature of the model that it enables an analysis of electromagnetic processes with various structures of the active power filter by only making minimal changes. It is also possible to take into account distortions of the network voltage shape and use various algorithms for compensation of higher harmonics. Electromagnetic analysis has been performed for a "network–nonlinear load" system in which harmonics are compensated by an active power filter based on a two- and three-level converter and by using passive first- and third-order PWM harmonic filters. The simulation was carried out for three algorithms of active power-filter operation in a distorted network, which provide maintaining of a constant active power consumption, a sinusoidal shape of the mains current, and a power factor equal to 1. [ABSTRACT FROM AUTHOR]

Investigation of the evolution of the parameters of crystallographic texture, microstructure, and mechanical properties of single-phase copper-based alloys with 10 and 30 wt % concentrations of Zn subjected to flat rolling in the coarse-grained state and preformed ultrafine-grained state are performed. A decrease in the stacking fault energy and an increase in the degree of reduction during flat rolling increases the values of the orientation distribution functions corresponding to twin orientations, decreases the grain size and coherent scattering regions, and increases the dislocation density and the twinning probability. These changes have a positive effect on the strength properties of the studied alloys. [ABSTRACT FROM AUTHOR]

Results are presented from investigation the evolution of the microstructure, mechanical properties, and electric conductivity of the Cu–0.5(wt %)Cr alloy in the ultrafine-grain state during cold rolling (with different degrees of reduction) and aging processes. The ultrafine-grain state is obtained using the equal-channel angular pressing. The ultrafine-grain state of the alloy is compared to its coarse-grain state. [ABSTRACT FROM AUTHOR]

The Configuration Database is an essential part of a complex of information systems that have been developed for the experiments of the NICA project at the Joint Institute for Nuclear Research. The developed database stores both a set of various configuration parameters, such as those required for setting the detectors into operation modes, for instance, working voltage, and descriptions of a sequence of software tasks to be started and run during experiment sessions. The corresponding Configuration Information System presented in the report is based on the implemented database and provides configuration information for data acquisition and other online processing systems, activating those hardware setups that are needed in the current experiment session. In addition, the system starts the described software tasks in the required sequence and allows managing them during sessions, including the transmission of messages between tasks and the update of some properties. The architecture of the Configuration Information System is presented as well, it has been implemented using the client-server model, where the server ensures interactions with the Configuration Database, and the client has been developed as a Web application to view and edit configuration parameters by users. [ABSTRACT FROM AUTHOR]

Information systems of experiments make a significant contribution to solving automation tasks of data collecting, storing, processing and analysis, and are used to support a lot of types of experiment activities. The article is devoted to one of information systems being actively employed in particle collision experiments—Event Metadata System, which provides a database containing information on summary properties of physics events and references to their storage location, and ensures fast search through stored event metadata. The Event Metadata System for the NICA experiments is based on the Event Catalogue and provides recording and managing information being necessary for a convenient search for events required in physics analyses. [ABSTRACT FROM AUTHOR]

The method of differential scanning calorimetry at various heating rates is used to measure the heat effect of the curing reaction of a EHD–MD grade chlorine-containing epoxy binder. Based on the experimental data, the kinetic parameters of the curing process are identified by the model-independent Friedman method. For the first time, an isoconversion thermokinetic diagram of the curing of a chlorine-containing epoxy binder is constructed and its glass transition temperature in the uncured state is determined, which makes it possible to evaluate the dependence of the latter on the degree of curing. [ABSTRACT FROM AUTHOR]

The structural parameters ensuring high strength and low electrical resistance have been analyzed in Cu–Cr alloys exposed to severe plastic deformation (SPD) and aging. Specific resistance and strength characteristics have been modeled for a Cu–0.5 wt % Cr alloy with a nanostructure state caused by SPD. A comparison of modeling data with experimental values reveals the validity of the approach chosen for describing the above states. The formation of nanostructure states with high strength and low electrical resistance is shown to be due to simultaneous effects depending on the treatment conditions of materials. [ABSTRACT FROM AUTHOR]

Abstract: As a result of U-Pb dating by LA-ICP-MS, the age of zircons from granitoids was determined to be 42.1-44.3 Ma for the rocks of first phase and 42.4-42.7 Ma for rhyolites from dikes of the second phase. On the basis of the geochemical studies of rocks, it was found for the first time that granodiorites of the Okhotsk massif (first phase) refer to A2-type granitoids. The most likely explanation of petrogenesis for A2-type granitoids of the Okhotsk complex is the gradual cessation of subduction as a result of deceleration of the Pacific Plate and the transition of the Ozerskii terrane to transform northward motion along the Merei suture zone with a certain role of syn-shear extension. Thus, the data obtained on the age and geochemistry of the Okhotsk complex granitoids suggest the possible time of geodynamic regime change in this area as about 43 Ma ago. [ABSTRACT FROM AUTHOR]

The paper describes the current state of the Geometry Database (Geometry DB) for the CBM experiment. The main purpose of this database is to provide convenient tools for: (1) managing the geometry modules; (2) assembling various versions of the CBM setup as a combination of geometry modules and additional files. The CBM users of the Geometry DB may use both GUI (Graphical User Interface) and API (Application Programming Interface) tools for working with it. [ABSTRACT FROM AUTHOR]

The calculations of the structure of dendrimer G1-8S-Dec (SiCHS) and its com-plexes with one, two, three, or four CuCl molecules were carried out for the first time using the density functional theory (DFT). The geometric structures of the complexes and the spin density distribution were determined. The states with the maximum multiplicity are most favorable for the complexes studied. The interaction energies of dendrimer G1-8S-Dec with CuCl molecules were calculated. Under standard conditions, the formation of complexes with a higher multiplicity of up to four CuCl molecules is most favorable. All the four considered complexes contain paramagnetic centers in which an unpaired electron is 'local-ized' on the tetrahedra with the central Cu atom and two S atoms and two Cl atoms at the vertices of the tetrahedron. [ABSTRACT FROM AUTHOR]

Results are presented of experimental x-ray diffraction analysis of the microstructure of VT6 titanium alloy billets in ultrafine-grained (UFG) state subjected to flat rolling. The UFG state was formed by six cycles of isothermal multiaxial forging at 650°C. The regularities of changes of the structural parameters (the lattice parameter, coherently scattering domain size, and microdistortions of the crystal lattice) are revealed depending on the degree of flat rolling reduction. [ABSTRACT FROM AUTHOR]

The results of research of symplectites from the Shavaryn-Tsaram (Hangaj plateau, Mongolia) and Bartoj (Dzhida basaltic field, Russia) alkali basaltic rocks are presented. The symplectite compositions and structures were studied, and the physical and chemical parameters at which primary megacrysts were transformed into secondary mineral assemblages were defined. It is established that both garnet megacrysts and garnet-clinopyroxene aggregates were formed at pressures of 10-13 kbar and temperatures over 1300°C. The transformation of garnet into minerals of the secondary assemblage is considered as solid state water assisted resorption of garnet at a depth corresponding to pressures of 4-8 kbar and temperatures ranging from 1000 to 1300°C. The kelyphitic rims on the garnet megacrysts resulted from melting of the megacrysts at the contact with the hosting alkali basaltic rock. [ABSTRACT FROM AUTHOR]

New surgical suturing materials with complex biological activities (antibacterial and stimulating tissue regeneration) have been developed. In vitro studies demonstrated pronounced and prolonged (up to 10-12 days) antibacterial activity. Experiments on 108 male albino rats proved the positive effect of the materials on the wound process: shortening of the inflammation period, more rapid transformation of the granulation tissue, more rapid epithelialization of the wound and its pronounced contraction. [ABSTRACT FROM AUTHOR]

Wolbachia pipientis is an obligately intracellular bacterium infecting a number of arthropod and nematode species. At the body level, Wolbachia infection may cause parthenogenesis, feminization of genetic males, male killing, or cytoplasmic incompatibility; it may also be asymptomatic. Of special interest is DNA transfer from Wolbachia to the host insect genome, which was discovered recently. At the cellular level, the effects caused by Wolbachia have been studied more poorly. Only one of the known insect cell lines has been obtained from an insect species (the mosquito Aedes albopictus) infected by Wolbachia. In this study, a continuous cell line Dm2008Wb1 has been obtained from embryos of Drosophila melanogaster infected under natural conditions. Wolbachia both persists in a primary cell culture and is retained upon its transformation into a continuous culture. The presence of this bacterium in cells in a free form is evidenced by the fact that tetracycline treatment can cure the cells of Wolbachia and by successful transfer of Wolbachia to another cell line (S2), where it has not been detected before. [ABSTRACT FROM AUTHOR]

To understand specific symbiotic relationships ensuring stable existing of the bacterium Wolbachia in laboratory strains of Drosophila melanogaster, the imago lifespan and senescence rate, as well as competitiveness, have been evaluated as components of fitness in females from the following laboratory strains: (1) inbred strain 95 infected with Wolbachia; (2) two uninfected strains obtained by tetracycline treatment that were genetically similar to strain 95; and (3) two control, uninfected, wild-type laboratory strains that were used to assess the possible effects of the antibiotic on the studied characters in the absence of Wolbachia. The results have shown that infected females have longer lifespan and competitiveness than females with the same genotype uninfected with Wolbachia. The increase in the senescence and mortality rates with age was also slower in infected females. It is noteworthy that tetracycline does not affect the lifespan of females from the two control, uninfected, wild-type strains. Therefore, the antibiotic is not the cause of the positive changes in fitness that were observed in infected females. The obtained results are the first direct evidence that the relationships in the Wolbachia-D. melanogaster symbiotic system are mutualistic rather than parasitic, at least in micropopulations adapted to laboratory conditions. [ABSTRACT FROM AUTHOR]

A model describing the nucleation of a new grain at the boundary of an existing grain during relaxation of the latent energy of junction disclinations formed in the course of plastic deformation is considered. This nucleation mechanism is shown to be energetically favorable. The dependence of the equilibrium size and misorientation of a nucleus on its shape is analyzed. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

The article discusses a study of interchromosomal gene conversion in early zygotic stage of diploid cleavage nucleus of Drosophila melanogaster. The study examines the molecular analysis of DNA heteroduplexes and the characteristics of molecular markers. The study also explores the gene conversion of diploid nucleus leading to reconstitution of homozygosity (ROH).

The cloned alpha-satellite DNA sequences were used to evaluate the specificity and possible variability of repetitive DNA in constitutive heterochromatin of human chromosomes. Five probes with high specificity to individual chromosomes (chromosomes 3, 11, 17, 18, and X) were in situ hybridized to metaphase chromosomes of different individuals. The stable position of alpha-satellite DNA sequences in heterochromatic regions of particular chromosomes was found. Therefore, the chromosome-specific alpha-satellite DNA sequences may be used as molecular markers for heterochromatic regions of certain human chromosomes. The homologous chromosomes of many individuals were characterized by cytologically visible heteromorphisms of hybridization intensity with chromosome-specific alpha-satellite DNA sequences. A special analysis of hybridization between homologues with morphological differences provided the evidence for a high resolution power of the in situ hybridization technique for evaluation of chromosome heteromorphisms. The approaches for detection of heteromorphisms in cases without morphological differences between homologues are discussed. The results obtained indicate that constitutive heterochromatin of human chromosomes has a variable amount of alphasatellite DNA sequences. In situ hybridization of cloned satellite DNA sequences may be used as a new general approach to analysis of chromosome heteromorphisms in man. [ABSTRACT FROM AUTHOR]

The chromosomal distribution of sequences homologous to 18 coned alpha satellite fragments was established by in situ hybridization. It appeared that all the cloned sequences were members of small repeated families located on single chromosome pairs. Among the sequences studied specific molecular markers for chromosomes 3, 4, 10,11,17,18 and X were found. Comparison of the hybridization spectra obtained under non-stringent conditions and of restriction site periodicities in different chromosome-specific families allowed the identification of three 'suprachromosomal' families, each located on a characteristic set of chromosomes. The three families together cover all the autosomes and the X chromosome. These data plus those reported previously allow part of the phylogenetic tree of chromosome-specific alpha satellite repeats to be drawn. Each suprachromosomal family has presumably originated from a distinct ancestral sequence and consists of certain types of monomers. Ancestral sequences have evolved into a number of chromosome-specific families by cycles of interchromosomal transfers and subsequent amplification events. The high homogeneity of chromosome-specific families may be a result of intrachromosomal homogenization of amplification units in chromosome-specific alpha satellite domains. [ABSTRACT FROM AUTHOR]

The microstructures and properties of copper- and aluminum-based nanocomposites processed through severe plastic torsional straining (SPTS) consolidation of metallic micrometer powders and ceramic nanopowders were investigated by transmission electron microscopy (TEM), X-ray diffraction (XRD), microhardness and electrical resistivity measurements, and mechanical tests. It was shown that the SPTS consolidation of powders is an effective technique for fabricating metal-ceramic nanocomposites with a high density, ultrafine grain size, and high strength. Copper samples processed under a high pressure of 6 GPa exhibited high failure strength and strain as well as unusual strain hardening. Superplastic-like behavior was found in Al-Al2O3 nanocomposite samples. [ABSTRACT FROM AUTHOR]

It has been revealed that the rheological explosion of a paramagnetic composite (manganese (III) polystyrene acetylacetonate-spatially complicated phenol) is accompanied by the generation of radio-frequency superradiance owing to the annihilation of triplet manganese complexes, as well as by the generation of current pulses. [ABSTRACT FROM AUTHOR]

Silica nanoparticles as carriers for targeted drug delivery to the heart were studied. Studies of hemodynamic parameters of rats after intravenous infusion of silica nanoparticles showed no acute toxicity. Intravenous infusion of silica nanoparticles to animals with ischemia−reperfusion of the myocardium led to accumulation of the nanoparticles in the focus of injury, which attests to possibility of passive targeted drug delivery to the myocardium. [ABSTRACT FROM AUTHOR]

The microstructures of ultrafine-grained nanostructured materials developed by severe plastic deformation are widely varied in their grain size and grain-size distribution; grain boundaries and their structures; lattice defects, especially dislocations; point defects; and impurities. All of these features can be influenced by the way severe plastic deformation is applied, and thereby have decisive effects on the physical and mechanical properties of the material. Probably, the most important factors determining microstructure are the imposed stress tensor, the degree and rate of strain, the temperature of deformation, the chemical composition of the deformed material, and the type of crystal lattice, showing that in order to develop specific properties, it is crucial to understand and optimize the microstructure. [ABSTRACT FROM AUTHOR]

A patient with an atypical clinical picture of 18p syndrome is described. By the in situ hybridization technique we localized the chromosome 18-specific cloned repetitive sequence to metaphase chromosomes of the patient. The predominant hybridization of the probe was found in pericentromeric regions of homologous chromosomes 18. The amount of pericentromeric DNA measured by in situ hybridization differed between homologous chromosomes; and the number of radioactive grains was statistically greater in the normal chromosome 18 than in the aberrant chromosome 18p. The results indicate that this probe may be useful in clinical cytogenetics for identification of aberrant chromosomes, localization of breakpoints, and studies of C-band DNA polymorphism of chromosome 18. [ABSTRACT FROM AUTHOR]