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The contribution of bends and constrictions by a superconducting film to the detection by a singlephoton superconducting detector is investigated. It has been shown that, for currents smaller than the minimal detection current of a straight film, the detection efficiency of a film with a constriction attains saturation upon an increase in the current, which coincides qualitatively with the behavior of this dependence observed in the experiment. It has also been found that the effect of bends in the film and the external magnetic field on the detection efficiency for low-energy photons is essential, while for high-energy photons no such influence is observed.

For the direct numerical simulation of the bag-breakup phenomenon, the Gerris flow solver was used. As an initial configuration for numerical simulation a drop of liquid was placed in the air flow. A drop of water with a diameter of 1 cm (the characteristic size of the perturbation from which the bag arises) placed in the air stream at a speed of 20 m/s corresponds best to the experimental situation, such a system is characterized by the Weber number We = 54. Modeling the dynamics of two media with very different densities, such as water and air, require a lot of computational time, so we used liquids that differ in density by a factor of 10, but to keep the same Weber number, we changed the other parameters of the problem. The calculation was carried out with keeping the same Reynolds number and also with the Reynolds number reduced and increased by a factor of 10. In our simulation just as in an experiment under the action of an air stream a drop is blown into a micro-sail that bursts to form a micro-spray. As the Reynolds number decreases (with increasing of viscosity of both media), the process of destruction of the drop after the formation of a micro-sail from it changes.

We have found experimentally that the rise times of voltage pulses in NbN superconducting single photon detectors increase nonlinearly with increasing detector length. We fabricated superconducting single photon detectors based on NbN thin films with a meander-like sensitive region of area from 2x2um2 to 11x11um2. The effect is connected with the dependence of the detector resistance, which appears after photon absorption, on its kinetic inductance and hence on detector length. This conclusion is confirmed by our calculations in the framework of the two-temperature model.

We studied the relationship between polymorphisms rs1800629 (-308G>A), rs28362491 (-94ins>del), and rs3834129 (-652ins>del) in the promoter regions of TNFA, NFKB1, and CASP8 genes, respectively, encoding TNF-α, nuclear transcription factor κB1 (NF-κB1), and caspase 8 (CASP8), and the risk and stages of chronic lymphocytic leukemia in ethnic Russians, residents of the Vyatka region of Russia. Allele -308A, genotype -308AA, and -308A genotypes (-308AA/-308AG) were associated with the risk of this pathology (OR=1.64, 95%CI 1.14-2.37, p=0.007; OR=4.48, 95%CI 1.20-16.80, p=0.02, and OR=1.57, 95%CI 1.05-2.36, p=0.03). In addition, NFKB1 allele -94del and genotype -94del/del were associated with advanced stages of the disease at the time of diagnosis (OR=0.66, 95%CI 0.46-0.97, p=0.03 and OR=0.43, 95%CI 0.20-0.92, p=0.03). These data suggest that -308G>A and -94ins>del polymorphisms of genes TNFA and NFKB1, respectively, can be involved in the pathogenesis of chronic lymphocytic leukemia.

The problems of cold and hot maintenance work on glassmaking furnaces at glass enterprises are presented. ‘DINUR’ JSC offers assistance and joint collaboration with glassmaking enterprises. New refractory articles, including the DSU-1 glass-dinas brand, which makes it possible to increase furnace life, are proposed. The characteristics of other refractory materials that can be used in different structural units of a glassmaking furnace (roofs, regenerators, suspended walls, doghouse arches and burner blocks) are examined in detail.

We theoretically study the dependence of the intrinsic detection efficiency (IDE) of superconducting single photon detector on the applied current $I$ and magnetic field $H$. We find that the current, at which the resistive state appears in the superconducting film, depends on the position of the hot spot (region with suppressed superconductivity around the place where the photon has been absorbed) with respect to the edges of the film. It provides inevitable smooth dependence IDE(I) when IDE $\sim 0.05-1$ even for homogenous straight superconducting film and in the absence of fluctuations. When IDE $\lesssim 0.05$ much sharper current dependence comes from the fluctuation assisted vortex entry to the hot spot located near the edge of the film. We find that weak magnetic field strongly affects IDE when the photon detection is connected with fluctuation assisted vortex entry (IDE$\ll 1$) and it weakly affects IDE when the photon detection is connected with the current induced vortex entry to the hot spot or nucleation of the vortex-antivortex pair inside the hot spot (IDE$\sim 0.05-1$)., Comment: 10 pages, 12 figures

The results of the study of the effective scattering area (ESA) of agricultural lands on drained peat bogs in the Ryazan' section of the Meshchera Lowland during different observation periods are presented. An experimental radar survey was made during spring-summer 1986-1987 by means of a side-looking airborne radar (SLAR) at a wavelength of 2.5 cm. In the processing of radar survey materials, the water surface of inland water bodies was used as a reference level. Invariant calibration curves and comparable quantitative estimates of the relative effective scattering areas for different agricultural features (open soils, pastures, sown fields of grain, and cultivated crops) were obtained for five survey times.

Reduction of the critical current in narrow superconducting NbN lines with sharp and rounded bends with respect to the critical current in straight lines was studied at different temperatures.We compare our experimental results with the reduction expected in the framework of the London model and the Ginsburg-Landau model. We have experimentally found that the reduction is significantly less than either model predicts. We also show that in our NbN lines the bends mostly contribute to the reduction of the critical current at temperatures well below the superconducting transition temperature.

We study dynamics of the order parameter in a superconducting film with transport current after absorption of a single photon. The system from the time-dependent Ginszburg-Landau equation, Poisson's equation for an electrical potential and the heat diffusion equation was solved numerically. For each photon energy in the absence of fluctuations, there exists a corresponding threshold current below which the superconducting state is stable and no voltage appears between the ends of the film. At larger currents the superconducting state collapses starting from the appearance of a vortex-antivortex pair in the center of the region with suppressed superconducting order parameter which has been created by the absorbed photon. Lorentz force causes motion of these vortices that heats the film locally and gives rise to a normal domain. When biased with the fixed current, the film latches in the normal state. In the regime when current via superconductor may change, which is more relevant for experiments, the normal domain exists only for a short time resulting in the voltage pulse with the duration controlled by the kinetic inductance of the superconducting film., 9 pages, 8 figures

The report presents data on narrow band (FWHM ≅ λmax/10) room temperature LEDs fabricated from InAsSbP/InAs heterostructures grown at Ioffe Institute and emitting in the 3.3-5.3 μm spectral range with emphasize on LEDs for methane (3.3 μm), carbon (4.3, 4.7 μm) and nitric (5.3 μm) oxides optical detection.

The results of experimental studies of arable land plots during the spring sowing campaign with the aid of K band side-looking airborne radar (SLAR) are given. The possibility of estimating the productive moisture content in soil in 0–50 and 0–100cm layers by radar-survey data and soil indication functions are shown in bare soil and winter crop plots using volumetric free moisture content as the measurement parameter.

Socialist countries devote much attention to calculating the effectiveness of foreign trade and to developing programs for the restructuring of exports and imports. Coefficients of the comparative effectiveness of the export of individual goods are constructed by comparing national economic outlays for the production of goods within the country with the monetary receipts from their sale. Analysis of these indices in combination with the efficiency coefficients of the corresponding import equivalents by groups of goods and by countries permits the construction of recommendations regarding optimization of the product structure of trade and the determination of the best geographical directions of trade relations. The obligatory consideration of the economic interests of all collaborating countries is the most important condition for restructuring the foreign trade of socialist countries on the basis of these calculations.

It was shown that reactivity of the nuclear matrix of thymocytes for antibodies against chromatin of the control and irradiated thymocytes and PDN did not change immediately and increased markedly 2 h following irradiation of rats with a dose of 10 Gy. The method of immunoblotting failed to reveal any qualitative differences in the protein content of the thymocyte nuclear matrix of the control and exposed rats.

In this work the antibodies were obtained against chromatin isolated from thymocytes of intact and irradiated rats (2 h after exposing to 10 Gy) and against polydeoxyribonucleotides (PDN) extracted from thymus nuclei 6 h following irradiation. All the antibodies under study reacted more readily with the chromatin obtained from the thymus of exposed rats than with the control chromatin. The complexes of DNA with the most firmly bound non-histone proteins, obtained from the three objects under study, reacted with the antibodies with equal efficiency. Thus, a higher reactivity of PDN and chromatin from thymocytes of exposed rats was associated with the decondensation of the latter leading to an increase in availability of a part of antigenic determinants. Using the immunoblotting method we failed to discover any qualitative differences in the protein composition of the chromatin from control and exposed rats.

A biphase change in poly (ADP-ribose) polymerase activity of the thymocyte chromatin was observed after 10 Gy irradiation of rats: during the first minutes the incorporation of 14C-NAD increased by 40% then started decreasing to make 110, 60 and 35% after 1, 2 and 3 h, respectively. Irradiation of rat thymus chromatin in vitro sharply decreased poly (ADP-ribose) polymerase activity. The possible role of changes in the poly (ADP-ribose) synthesis in the activation of nuclear Ca/Mg-dependent endonuclease and in the postirradiation degradation of the thymocyte chromatin is discussed.

Uninterrupted methods of specific and prophylactic treatment of pregnant women and children, born from syphilitic mothers, were offered. A new preparation--novocainic salt of benzyl penicillin was used in specific and prophylactic treatment of pregnant women.

Die eutektische Legierung InAs-FeAs mit einkristalliner Matrix wird nach der Czochralski-Methode gezuchtet.

Localization of immunogenic tissue-specific proteins in chromatin regions, hypersensitive to endogenous nucleases, has been studied using rabbit antibodies against rat thymus chromatin. It is shown that the first 1–2,5% of the chromatin (calculating on DNA), released by Mg2+-, Mn2+-, and Ca2+/Mg2+-dependent nuclear endonucleases are drastically enriched in tissue-specific antigenic determinants. The released chromatin fractions are found to contain a heterogeneous set of nonhistone proteins and are deficient in histones. The cleavage of nuclear DNA by endogenous acidic nuclease, independent on bivalent ions, resulted in a significantly less enrichment of the released fractions with immunogenic proteins.

The properties of rat liver and thymus non-histone and nuclear sap proteins were compared. The distribution of total, labile-bound and 0.35 M NaCl extractable non-histone proteins from one organ on polyacrylamide-gel electrophoresis in the presence of sodium dodecylsulphate is quite similar. On electrophoresis non-labelled and 32P-labelled non-histone and nuclear sap proteins from one organ differ from one another both qualitatively and quantitatively. We did not find an appreciable difference between non-labelled non-histone proteins isolated from liver and thymus. The distribution of 32P-labelled non-histone proteins from various organs differs quantitatively rather than qualitatively. Non-labelled and 32P-labelled nuclear sap proteins from liver and thymus differ significantly. 'Free' nuclear sap proteins and the proteins of ribonucleoprotein particles from thymus nuclei contain a great quantity of identical polypeptides, whereas other polypeptides are specific to each of these protein fractions. Upon incubation of nuclei with [gamma-32P]ATP the label is incorporated into all the fractions of nuclear protein. The nuclear proteins are phosphorylated at decreasing rates in the order: labile-bound non-histone proteins greater than firmly bound non-histone proteins greater than 'free' nuclear sap proteins = proteins of ribonucleoprotein particles greater than histones. Nuclear sap and non-histone proteins contain protein kinases capable of phosphorylating both these proteins and histones. Histone phosphorylation is sharply inhibited after addition of DNA, the protein kinases of nuclear sap phosphorylating less effectively the histones complexed with DNA than the non-histone proteins. Both non-histone and nuclear sap proteins contain fractions interacting in vitro with DNA. Denatured DNA binds twice as much 32P-labelled nuclear sap proteins and a little more 32P-labelled non-histone proteins than native DNA. Denatured DNA binds non-histone and nuclear sap proteins much more effectively than native DNA. It was shown by the membrane filter technique that the major part of the nuclear sap and non-histone proteins interacting with native DNA binds to it non-specifically. A certain portion of non-histone and nuclear sap proteins interacts specifically with homologous denatured DNA. The possible role of non-histone and nuclear sap proteins in the regulation of transcription is discussed.

Rat thymocyte chromatin was dissolved in 1.0 or 2.0 M NaCl and the dissociated proteins were separated by ultracentrifugation or gel filtration on Sephadex G-200. Rabbit antibodies against tissue-specific antigenic determinants of thymus chromatin interact with "depleted" deoxynucleoproteins and not with dissociating proteins. The DNA complex with firmly bound proteins obtained in 2 M NaCl was treated with DNAase I; this treatment had no effect on proteins interaction with antibodies. Thus, tissue-specific antigenic determinants can be related to the most firmly bound nonhistone proteins.

Ca2+,Mg2+-dependent nuclease was isolated from calf thymus chromatin by stepwise chromatography on DEAE-Sepharose, CM-Sephadex and DNA-Sepharose. The enzyme was purified more than 700-fold. SDS-PAGE electrophoresis revealed one protein band possessing an enzymatic activity. The molecular mass of the nuclease as determined by gel filtration is 25700 Da, that determined by 12% SDS polyacrylamide gel electrophoresis is 28,000 Da. In the presence of various ions the enzyme activity decreases in the following order: (Ca2+ + Mn2+) greater than (Ca2+ + Mg2+) greater than Mn2+; the pH optimum is at 8.0. In media with Mg2+, Ca2+, Co2+ and Zn2+ the nuclease is inactive. Some other properties of the enzyme are described.