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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]

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]

Presents a study which performed quantitative x-ray diffraction measurements on a nanocrystalline copper sample made by severe plastic deformation. Experimental results; Discussion and conclusions.

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 presented work considers one of the promising ways of enhancement of strength in ultra fine-grained (UFG) metal materials produced as a result of application of severe plastic deformation techniques. Mathematical modeling showed that structure design in UFG Al and Ti alloys enabled significantly increasing their strength. By introducing impurity atoms with fixed concentration in the matrix and subjecting material to relevant processing, one can form UFG structures with a high strength including at elevated temperatures. [ABSTRACT FROM AUTHOR]

This paper presents the results of experimental studies on the evolution of structure, crystallographic texture and the anisotropy of strength properties in the volume of Ti Grade 4 billets subjected to continuous equal-channel angular pressing (ECAP). Continuous ECAP is performed at temperatures of 200 °C, 400 °C, and 450 °C, with 1 to 8 passes, using route BC. The methods of X-ray diffraction analysis are employed to investigate the effect of processing regimes and strain degree during continuous ECAP on the structure of the material under study. As a result of computer modelling of the crystallograpic texture evolution, the regularities in the formation of preferred orientations and the anisotropy of strength properties are established, and the activity of various slip systems and twinning systems in titanium billets, depending on the number of ECAP passes, is evaluted. Estimation of the anisotropy of strength properties, based on building of yield contours, shows that an increase in the number of passes of continuous ECAP promotes the formation of a more isotropic structure. The obtained results allow to explain and predict the deformation behavior of nanostructured Ti Grade 4 with consideration of its microstructure and crystallographic texture parameters. [ABSTRACT FROM AUTHOR]

A two-phase emission detector containing 5 kg of liquid Xe is installed at the horizontal experimental channel of the research nuclear reactor IRT MEPhI to measure the liquid Xe response to nuclei recoils with kinetic energies below 1 keV. Preliminary tests have demonstrated that \geq 15~\mu\s electron lifetime in liquid Xe and \sim 10 photoelectrons single ionization electron signal are achieved. These parameters are sufficient to detect and identify events at the single electron level. [ABSTRACT FROM PUBLISHER]

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]

The Online Software is the global system software of the ATLAS data acquisition (DAQ) system, responsible for the configuration, control and information sharing of the ATLAS DAQ System. A test beam facility offers the ATLAS detectors the possibility to study important performance aspects as well as to proceed on the way to the final ATLAS DAQ system. Last year, three subdetectors of ATLAS-separately and combined-were successfully using the Online Software for the control of their data taking. In this paper, we describe the different components of the Online Software together with their usage at the ATLAS test beam. [ABSTRACT FROM AUTHOR]

Describes a Process Management component of the online software of the ATLAS experiment data acquisition system. Purpose of the Process Manager; Design challenges of the software agent; Architecture of the Process Manager system; Performance and scalability of the system; Conclusions.

Presents a study which discussed an overview, performance and scalability of a computer software applied in a data acquisition system prototype. Purpose of the system prototype; Components of the software; Summary.

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).

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]

Titanium alloys have high specific strength and corrosion resistance, which have promising applications in industry. However, the machinability of titanium alloys is limited due to their crystal lattice and physical properties. Thus, in recent years, the superplastic forming of titanium alloys has been intensively developing, in particular, forming at low temperatures and/or high strain rates. In this work, a tensile test of low-cost Ti-2Fe-0.1B alloys was carried out at a temperature of 550~750 °C and a strain rate of 1 × 10−3 s−1~1 × 10−2 s−1. The results showed that the alloy exhibited good superplasticity even at a high strain rate (1 × 10−2 s−1) and a low deformation temperature of 550 °C; the elongation of the alloy in this state reached 137.5%. The high strain rate sensitivity coefficient m (0.3) and the maximum elongation (452%) were obtained at a strain rate of 1 × 10−3 s−1 and a temperature of 750 °C. Characteristics of the microstructure showed that during superplastic deformation, the recrystallization and grain boundary sliding of the alloy phases were accelerated, which could be ascribed to the effect of the element Fe. At the same time, the TiB phase located around the primary elongated α grains could also induce dynamic recrystallization and dynamic globularization during deformation. [ABSTRACT FROM AUTHOR]

In the present study, a novel Ti-2Fe-0.1B alloy was processed using equal channel angular pressing (ECAP) via route Bc for four passes. The isochronal annealing of the ultrafine-grained (UFG) Ti-2Fe-0.1B alloy was conducted at various temperatures between 150 and 750 °C with holding times of 60 min. The isothermal annealing was performed at 350–750 °C with different holding times (15 min–150 min). The results indicated that no obvious changes in the microhardness of the UFG Ti-2Fe-0.1B alloy are observed when the annealing temperature (AT) is up to 450 °C. Compared to the UFG state, it was found that excellent strength (~768 MPa) and ductility (~16%) matching can be achieved for the UFG Ti-2Fe-0.1B alloy when annealed at 450 °C. The microstructure of the UFG Ti-2Fe-0.1B alloy before and after the various annealing treatments was characterized using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). It was found that the average grain size remained at an ultrafine level (0.91–1.03 μm) when the annealing temperature was below 450 °C. The good thermal stability of the UFG Ti-2Fe-0.1B alloy could be ascribed to the pinning of the TiB needles and the segregation of the Fe solute atoms at the grain boundaries, which is of benefit for decreasing grain boundary energy and inhibiting the mobility of grain boundaries. For the UFG Ti-2Fe-0.1B alloy, a recrystallization activation energy with an average value of ~259.44 KJ/mol was analyzed using a differential scanning calorimeter (DSC). This is much higher than the lattice self-diffusion activation energy of pure titanium. [ABSTRACT FROM AUTHOR]

The mechanisms of high-speed deformation of ultrafine-grained copper produced during severe plastic deformation by equal-channel angular pressing were analyzed using numerical modeling in comparison with those in the case of coarse-crystalline copper. The activity of annihilation processes during nonconservative motion and double cross slip of dislocations was estimated. Their effect on the macroscopic behavior of samples is shown. [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]

The experimental studies of the properties of the hardened surface layer, developed by the microarc oxidation method (MAO) on the surface of Al-Si ingots from AK12D alloy have been presented here. The effect of concentration of the electrolyte components on the properties of the MAO coating, such as microhardness, thickness, porosity have been studied. The corresponding regression equations to estimate the influence of the process parameters on the quality of the developed MAO-layer, have been set up. [ABSTRACT FROM AUTHOR]

Abstract: Regardless of the origin of structure irregularities of materials, the recognition of their spatial distribution in a sample or constructing elements is a great research problem. One of the most effective and non-destructive tools used for this purpose is the X-ray diffraction technique, assisted by an appropriate experimental method and data processing. The work presents the results of investigations of planar distribution of crystallographic texture and stress irregularities manifested by changes of diffraction effects registered by the X-ray technique. As an example, the introduced method is tested on a titanium rod after severe plastic deformation process. [Copyright &y& Elsevier]

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]

The ATLAS collaboration at CERN operated a combined test beam (CTB) from May until November 2004. The prototype of ATLAS data acquisition system (DAQ) was used to integrate other subsystems into a common CTB setup. Data were collected synchronously from all the ATLAS detectors, which represented nine different detector technologies. Electronics and software of the first level trigger were used to trigger the setup. Event selection algorithms of the high level trigger were integrated with the system and were tested with real detector data. The possibility to operate a remote Event Filter farm synchronized with the ATLAS Trigger and Data Acquisition System (TDAQ) was also tested. Event data, as well as detector conditions data, were made available for offline analysis. [ABSTRACT FROM AUTHOR]

In the ATLAS experiment at the LHC, the output of read-out hardware specific to each subdetector will be transmitted to buffers, located on custom made PCI cards ("ROBINs"). The data consist of fragments of events accepted by the first-level trigger at a maximum rate of 100 kHz. Groups of four ROBINs will be hosted in about 150 Read-Out Subsystem (ROS) PCs. Event data are forwarded on request via Gigabit Ethernet links and switches to the second-level trigger or to the Event builder. In this paper a discussion of the functionality and real-time properties of the ROS is combined with a presentation of measurement and modelling results for a testbed with a size of about 20% of the final DAQ system. Experimental results on strategies for optimizing the system performance, such as utilization of different network architectures and network transfer protocols, are presented for the testbed, together with extrapolations to the full system. [ABSTRACT FROM AUTHOR]

Abstract: Titanium alloys have been the mostly used materials of choice for medical implants. They are generally considered chemically inert, biocompatible with human tissue and resistant to corrosion by human body fluids. However the small percentages of vanadium and aluminum atoms (main alloying elements) contained in the alloy are potentially toxic. Normal wear can lead to deterioration of the implant and the release of alloying elements into the body. The novel process—a combination of severe plastic deformation with traditional metal forming process—can produce special material structure with nanosize grains. This nanostructured material has high tensile and fatique strength and even the enhanced ductility. Pure titanium is chemically and biologically more compatible with human fluids and tissue than other materials but the coarse-grained titanium is too weak for prostheses that must bear heavy loads such as leg or hipbone implants. The strength of pure titanium is less than half the strength of Ti–6Al–4V alloy what is mostly have used for medical implants. By using the mentioned novel process the strength of pure titanium with nanosize grains can be increased even higher than in case of the conventional Ti–6Al–4V alloy. This new process creates medical implants that are strong enough to bear heavy loads without failure. The implant material is corrosion resistant and biocompatible with human body organs and fluids so it can remain in the body for years. [Copyright &y& Elsevier]

We present a new giant magnetoresistance (GMR) material composed of polyaniline, polystyrene, sulfur, manganese acetylacetonate, lanthanum, and praseodymium chlorides. These compounds were mixed and processed mechanochemically to obtain thin films. External magnetic field of 6000 Oe increases conductivity of films by more than 300%. Analysis of transient current kinetics after application of constant voltage (10 V) to samples showed the existence of three types of charge carriers, which we identified as e-, H+, and Cl-. Contribution of functional groups of polyaniline and elemental sulfur S in the formation of the above charge carriers in this new GMR composite material is discussed. [ABSTRACT FROM AUTHOR]

Coordination polymers exhibiting magnetic properties can be considered as promising materials for magnetic applications. We obtained such materials by means pf mechanochemical incorporation of binuclear metal complexes Mn–O–Mn into polystyrene. Incorporation of binuclear manganese complexes was achieved by using substituted benzoquinones (organic acceptors) as intermediate ligands that react with manganese acetylacetonate and provide new coordination and stabilization of manganese in different valence states. Magnetic transitions in this system are due to reversible disproportionation process Mn3+–O–Mn3+⇔Mn2+–O–Mn4+ in the binuclear complex. The structure of the binuclear complex was obtained using ab initio calculations. [ABSTRACT FROM AUTHOR]

We report on mechanochemical synthesis and magnetic and electric properties of organic polymeric semiconductor that contains paramagnetic and ferromagnetic particles. As starting materials we used polyaniline (emeraldine base), polystyrene, FeCl3, and elemental sulfur. These components were chosen for the purpose of obtaining semiconductor polymer composite containing magnetic iron nanoparticles and having flexible thermomechanical properties. The presence of nanoparticles was evidenced by scanning electron microscopy. The value of conductivity of the Fe-doped polymer composite was increased by several orders of magnitude compared to the initial undoped polyaniline. Temperature dependence of the conductivity shows semiconductor character of the composite material. [ABSTRACT FROM AUTHOR]

By means of mechanochemical synthesis we obtained a coordination polymer containing binuclear manganese complexes with organic catechol/ortho-quinone ligands. The reaction system contained polystyrene, manganese acetylacetonate, and donor-acceptor mixture catechol/ortho-quinone. Electron paramagnetic resonance (EPR) and infrared spectroscopic data show that the binuclear manganese complex is covalently linked to the chain of polystyrene. Theoretical EPR spectrum analysis revealed a triplet state of the complex with two nonequivalent manganese ions coupled to each other by spin exchange. The type of magnetic coupling between manganese ions in this system is similar to the one in manganese based inorganic magnetic materials. [ABSTRACT FROM AUTHOR]

We investigated paramagnetic properties of binuclear niobium complexes Nb-O-Nb with two nonequivalent Nb4+ ions in lithium-niobium phosphate glasses sLNPGd, in the environment of catechol/ortho-quinone ligands and in polyethylene. Experimental electron paramagnetic resonance spectrum analysis revealed nonequivalent distribution of the charge and electron spin density between two Nb atoms. Mechanochemical interaction of LNPG with an organic donor-acceptor mixture catechol/ortho-quinone followed by organic solvent extraction leads to the formation of a new binuclear complex with catechol/ortho-quinone ligands. This complex can be further incorporated into polyethylene matrix to form the complex with properties close to the complex in LNPG. [ABSTRACT FROM AUTHOR]

We report on synthesis of Co, Ni, and Fe nanoparticles by the action of elastic wave pulses on solid phase sandwich type samples containing metal salt, reducing agent, polyethylene, and polyacrylamide. The formation of metal nanoparticles is evidenced by ferromagnetic resonance and scanning electron microscopy. The product yield for the nanoparticles formation has a threshold character with the pressure in the elastic wave pulse. The maximum amount of Co, Ni, and Fe nanoparticles is observed around 20 kbar of pressure in elastic wave pulses. The presence of polyacrylamide in reaction composites increases the stability of metal nanoparticles to oxidation by two orders of magnitude. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Chromium complexes, where ortho-quinone ligands are covalently linked to polymeric chains of polyethylene, polystyrene, and copolymer of ethylene and vinylacetate are studied. The results of infrared and electron paramagnetic resonance spectroscopic studies of chromium coordination polymers show that covalent linking of quinone ligands is accompanied by the change in the valence states of chromium Cr(III)↔Cr(IV)↔Cr(V). The ligand field of the triplet Cr4+ ion is close to the one in Cr-doped Y2SiO5, a laser material in the visible and infrared regions. Therefore some useful magnetic and/or optical properties in such transition metal coordination polymers can be expected. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of joint welds formed by linear friction welding (LFW) in in Al-Cu-Mg alloy was investigated. Joint welds of two samples of rectangular shape do not possess any macroscopic defects and are characterized by high strength. The substantial transformation of the microstructure occurs in the weld zone as a result of plastic deformation and deformation heating during LFW. [ABSTRACT FROM AUTHOR]

The investigation studies the properties of hardened surface layers, developed with the microarc oxidation method (MAO) on ingots of a Al-Si alloy. It has been proved that properties of the developed surfaces (microhardness, thickness, porosity and corrosion properties) depend on the concentration of electrolyte components. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies of the properties of hardened surface layers formed by micro-arc oxidation on the workpiece surfaces of aluminum alloy Al-12Si-Mg-Cu-Ni. The authors attempted to determine the influence of micro-arc oxidation modes on the properties of the modified layers. Investigation of the adhesion strength of the surface layers formed at different concentrations of electrolyte components and analysis of the change in coatings adhesion characteristics after thermal cycling were presented. [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]

Abstract: Characteristic properties of a Geiger Mode APD (G-APD) in a THGEM-based cryogenic two-phase Ar avalanche detector were studied in view of potential applications in rare-event experiments. G-APD signal amplitude and noise characteristics at cryogenic temperatures turned out to be superior to those at room temperature. The effective detection of avalanche scintillations from THGEM-multiplier holes in two-phase Ar has been demonstrated using a G-APD without wavelength shifter. At an avalanche gain of 60, the avalanche scintillation yield measured by the G-APD was as high as 0.9 photoelectrons per avalanche electron, extrapolated to 4π acceptance. [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]

A model is proposed for the formation of the substructure in polycrystals during plastic deformation. According to this model, fragmentation of a grain occurs through the formation of a system of diagonal low-angle boundaries, which originate at the edges of a rectangular grain. Misorientation boundaries form through relaxation of a nonsymmetric junction quadrupole disclination configuration accumulated at the grain corners under severe deformation when the disclination strength reaches a certain critical value. The energetics of this process is analyzed. A general case is considered where the disclinations at the junctions of the chosen grain differ in strength. The energetic approach used makes it possible to determine the misorientation angle ωx of the resulting boundaries corresponding to the maximum energy gain and to find the dependence of this angle on the degree of asymmetry of the quadrupole configuration of junction disclinations. According to the proposed model, the splitting of a grain with a short edge greater than 0.5μm is energetically favorable and decreases the latent energy of the grain for any ratio between the junction disclination strengths if the grain length-to-width ratio is less than 30. It is shown that the minimum possible grain size in the proposed model does not exceed 0.1μm. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

The paper presents the results of the application of a newly developed method to study deformation and fracture processes in specimens produced by linear friction welding. This method combines mathematical modeling and experimental mechanical testing. By application of this method it has been demonstrated that during uniaxial testing of welded joint specimens of Ti-6Al-4V and Ti-6Al-3.5Mo shear bands occur at an angle of 45°. Fracture of the specimen took place near the weld line, in the heat-affected zone, of the Ti-6Al-4V alloy. Microcracks started in the centre of the tested specimen. Recording of acoustic emission signals during tensile testing identifies the appearance of the initial microcracks and can predict the precise moment of fracture. [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]