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The results of the development of a radiation-tolerant robotic complex URS-2 for operation in hot cells at nuclear enterprises are presented. The robotic complex consists of several original components: robotic arm, control device with force feedback, control panel with hardware buttons and touch screen, control computer with system and application software, control-and-power cabinet. The robotic manipulator has 6 degrees of freedom, replaceable pneumatic grippers and is characterized by high radiation tolerance, similar to that of mechanical master-slave manipulators. The original design of the control device based on the delta-robot model that implements a copying mode of manual control of the robotic complex with force feedback is presented. The hardware and software solutions developed has made it possible to create a virtual simulator of the RTC for testing innovative methods of remote control of the robot, as well as teaching operators to perform technological tasks in hot cells. The experimental model of the robotic complex has demonstrated the ability to perform basic technological tasks in a demo hot cell, both in manual and automatic modes.

Detection and study of biologically active compounds seems a promising area of research in cancer diagnostics and therapies. The glycoprotein and polysaccharide fractions showing high cytotoxicity towards several human and animal cancer cell lines: A549, Hep-2, HeLa, С6 and SPEV-2 were isolated from basidiomycete Lentinus edodes vegetative mycelium and fruiting body and further characterized. It was found that water-soluble glycoprotein fractions caused the most significant, 70-100% inhibition of metabolic activity of SPЕV-2, А549 and С6 cell lines. The effective concentrations of glycoprotein fractions reducing the viability of cancer cell lines were determined. The protein and subunit composition of fractions was studied; the highly active galactose-specific lectins were found to be present in these fractions. Comparative analysis of transcriptomes of L. edodes vegetative mycelium, fruiting body and primordium revealed the presence of carbohydrate-binding glycoproteins (lectins) specific for each stage of basidiomycete morphogenesis. Histological examination revealed some morphological indicators of immune system activation and the absence of toxic effect on gastro-intestinal mucosa of animals at peroral administration of fungal glycoprotein fractions. Fungal protein and, in particular, lectin preparations derived from L. еdodes vegetative mycelium might be considered as novel prospective tools in cancer diagnostics and therapies.

This article focuses on a previously unexplored episode in the history of international relations, related to the temporary suspension of the Lausanne Conference on the Middle East in February 1923, which threatened to revive a state of war between Turkey and the Entente powers. This crisis, which unfolded at the same time as the Franco-Belgian occupation of the Ruhr, had a significant impact on the final outcome of the peace settlement in the Middle East enshrined in the Lausanne Treaty. The aim of the article is to determine the place and role of this crisis in the process of establishing a new system of international relations after the Great War and its interconnection with other major events and processes of this period. The author consecutively analyses two phases of this crisis, the first relating to the Turkish demand for the withdrawal of the ships of the Allied Powers from its ports, and the second to the sharp aggravation of the situation on the Turkish-Syrian border. The crisis demonstrated the inability of France to defend its interests in the Middle East “single-handedly” and its forced dependence on British policy. Thus, its role in the development of international relations in the Middle East was similar to that played by the Ruhr Crisis in Europe. The paper draws on numerous sources, primarily British, French and Italian diplomatic documents.

The work described in this paper aims at the development of a networkable, intelligent embedded system application, which is used for data acquisition and analysis in traffic flows. The main components of the sensor system and their interaction are explained. The sensor system is constructed in such a way that, in addition to the use of magnetic field sensors, further sensors which are useful for the respective detection task can be added. Furthermore, measuring procedures in the laboratory and in field trials on the road are described and illustrated. A selection of the results is presented.

A duality of two categories is introduced. It generalizes the Malcev description of torsion free finite rank abelian groups. An equivalence of two categories is also introduced. It generalizes the Kurosh description of p -primitive groups. The composition of the duality and the equivalence is the duality earlier introduced by W. Wickless and the author. It is shown that the last duality preserves exactness for short exact sequences of homomorphisms.

Excitonic carrier dynamics taking place in In x Ga 1-x N/Gal4 multi-quantum-well systems have been studied by low temperature picosecond time resolved photoluminescence (LT-TRPL), HR-TEM, XPS, Dynamic TOF-SIMS, and quantum mechanical simulation methods. Both time-integrated and time-resolved photoluminescence spectra of In x Ga 1- x N/GaN multi-quantum-wells with different well thickness and Indium composition were measured at 10 K. We assigned the natural radiative lifetime of each sample from the time resolved PL. We observed that the natural radiative lifetime of In In x Ga 1-x N/GaN multi-quantum-wells depends strongly on the well thickness and Indium composition. To support the measured natural radiative lifetimes, excitonic oscillator strengths of the In x Ga 1-x N/GaN multi-quantum-wells were calculated by using a 2-D particle-in-a-box model as functions of well thickness and Indium composition. Values of the well thickness and Indium compositions from the HR-TEM and XPS compositional depth profiling were used to achieve more realistic computational results and to corroborate the measured natural radiative lifetimes of In x Ga 1-x N/GaN multi-quantum wells.

In this paper “group” always means “abelian group”. For a group G let T = T(G) be the torsion part and, for a prime p, let T p = T p (G), be the p-torsion part of G.

Calcium phosphate (CaP) based materials are widely recognized as the most suitable matrix for bone tissue engineering. The cationic and anionic substitution of CaP structure by the elements and groups of biological importance is the effective way to improve the properties of CaP based substances to achieve the material’s desired parameters. Some aspects of application of the conventional electron paramagnetic resonance (EPR) approaches for characterization of CaP powders and ceramics such as hydroxyapatite (HAp) and tricalcium phosphates (TCP) containing intrinsic impurities or intentional dopants like manganese, copper, iron are demonstrated. It is shown that the radiation induced EPR spectra for the nominally pure HAp and TCP reveal the presence of stable nitrogen containing or hydrogen radicals and depend on the CaP synthesis route. It is found that the experimental values of the hyperfine splitting (A) for the nitrogen containing radicals in TCP differ from those known for HAp. The observed narrowing of the central EPR line and increase of its amplitude with the concentration of Mn2+ in the range from 0.05 up to 5 wt. % could be exploited for the quantitative determination of manganese in CaP. Analysis of the EPR spectra of the iron containing CaP allows to determine the presence of iron in Fe3+ state. The values of the components of g and A for Cu2+ ions in TCP are determined and it is demonstrated that they can be influenced by the presence of the codoped Mn2+. Therefore, conventional EPR can be used to study cation-cation codoping.

Carbonate hydroxyapatite (CHA) is an analogue of the mineral component of bone tissue. Synthetic CHA is thermally unstable: it readily decomposes with carbon oxide evolution when sintered to ceramics. Its thermal stability has been studied as affected by partial isomorphic substitution of sodium for calcium intended to compensate a possible charge imbalance induced by CO32- groups. Investigative tools were thermogravimetry and FTIR spectroscopy of the condensed vapor produced by heating CHA samples doped with 0.4 and 0.8wt % sodium. Sodium does not improve the thermal stability of CHA: weight loss on heating increases with increasing sodium level; evolution of carbon oxides occurs at lower temperatures and more intensively. Sodium enhances the generation of B-type defects (CO32- -> PO32- substitutions); these defects are thermodynamically less stable than AB-type defects (CO32- -> PO32-,OH- substitutions), which are characteristic of sodium-free CHA.