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By present time safety problems of gene therapy are widely discussed among scientists of all world. In this review results of clinical researches are summarized; explanations concerning side effects of vectors integration are given; factors that can cause genotoxicity are discussed. Approaches which can save or increase clinical efficacy of gene therapy with use as targets hematopoietic stem cells, thus significantly reduced risk of leukemia development and other side effects related to vectors including in genome, are presented.

In this article, we present a new Co2FeSi glass-coated microwire obtained by Taylor-Ulitovsky technique with nanocrystalline structure consisting of a mixture of bcc phase (lattice parameter, a = 5.640 Å, crystalline grain size, Dg = 17.8 nm) in as-prepared sample. The annealing temperature was fixed at 873 K, and the annealing time was 1 and 6 h. The annealing resulted in a significant increase of such nano-grains up to (31.6 nm). Perfect square hysteresis loops have been observed in all annealed samples at a wide temperature range (55–400 K) that are not seen in the as prepared sample. The thermal magnetic behavior for the annealed samples shows dramatic magnetic behavior at low temperature. Large irreversibility magnetic behavior with a blocking temperature (Tb = 150 K) has been observed for annealed sample for 1 h. Critical temperatures of 155 K and 105 K have been detected for annealed samples for 1 h and 6 h, respectively, where the behavior of M−H loops, coercivity and remanence changed. Below the critical point the M−H shows wasp-waisted, multistep magnetic behavior and complex magnetic reversal mechanism is supposed. The anomalous magnetic behavior is due to the coexistence of the ordered and disordered phases induced by annealing conditions below the room temperature. The difference in the magnetization behaviour, remanence, and coercivity values for Co2FeSi glass-coated microwires samples indicates the influence of internal stresses created by the presence of the glass coating. These finding opens the door to design spintronic devices based on the magnetization switching.

Состояние здоровья в значительной мере определяет качество жизни человека. Это значимый социально-экономический ресурс и основа национальной безопасности страны.

The effect of the type of doping (surface (I) or bulk (II) doping) on the character of the dipole plasmon mode in semiconductor CdSe nanocrystals has been studied. It was found that in case I (donors located on the surface of the nanocrystal) the collective mode had a rotational character and only the angular degrees of freedom were excited. On the contrary, in case II the charge of the dopant impurities was distributed throughout the system and plasmon excitation was the oscillation of delocalized charge carriers in the direction normal to the surface. It was shown that the position of the resonance line was determined not only by the concentration of free charges, but also by the character of their collective motion determining by the type of doping.

In this article we evaluate the possibility of using glass coated magnetic microwires as an alternative to optical fiber devices in structural health monitoring in the railway industry. The effect of applied stress on hysteresis loops of Fe71.80B13.27Si11.02Nb2.99Ni0.92 and Co65.34Si12.00B10.20Cr8.48Fe3.90Mo0.08 microwires has been studied and analyzed. An interpolation function has been obtained relating the coercitivity Hc with the applied stress.

Plant toxins – ricin and abrin, obtained in a purified form from the beans of the castor bean and Abrus precatorius respectively, are considered by Western experts as potential damaging agents of a biological nature. The purpose of this work is to consider the danger of using ricin and abrin as agents of biological terrorism, as well as to assess the existing approaches and means for identifying these toxins, treating the intoxication caused by them, as well as the level of development of vaccine preparations. Both toxins have a similar molecular structure and mechanism of action. They consist of two subunits – A and B, resistant to high temperatures and extreme pH values. The mechanism of their damaging action is based on irreversible inhibition of the process of protein synthesis. The LD50 of ricin for humans, according to various sources, is 3 µg/kg for inhalation and intravenous intake, 22–25 µg/kg for enteral intake, and about 500 µg/kg for subcutaneous intake. Abrin is more toxic than ricin, with an LD50 for humans ranging from 0.1 µg/kg to 1 µg/kg depending on the route of entry. In case of enteral poisoning with ricin and abrin, the victims develop symptoms of gastroenteritis within a few hours: nausea, vomiting and pain in the abdominal cavity and chest, diarrhea. Bleeding from various parts of the gastrointestinal tract may be present. In future, general intoxication symptoms (headache, weakness, fever) and symptoms of multiple organ damage (acute renal failure and acute liver failure) develop. In the terminal stage, symptoms of vascular shock and vascular collapse are expressed. Death usually occurs on the third day or later. Cases of the use of ricin and abrin for criminal and terrorist purposes are described in the article. The main approaches and modern means of indication, means of treating ricin and abrine intoxication, as well as the state of development of vaccine preparations are shown. The given data show that the danger of these toxins as damaging agents is underestimated in Russia. It is necessary to develop diagnostic test systems that allow early detection of intoxication with plant toxins in the affected and the toxins themselves on environmental objects, as well as specific means for the treatment and prevention of acute poisoning with ricin and abrin.

We studied Ni2FeSi-, Co2FeSi-, and Co2MnSi-based full-Heusler alloy glass-coated microwires with the same geometric parameters, i.e., fixed nucleus and total diameters, prepared using the Taylor–Ulitovsky method. The fabrication of X2YZ (X = Co and Ni, Y = Fe and Mn, and Z = Si)-based glass-coated microwires with fixed geometric parameters is quite challenging due to the different sample preparation conditions. The XRD analysis showed a nanocrystalline microstructure for all the samples. The space groups Fm3¯m (FCC) and Im3¯m (BCC) with disordered B2 and A2 types are observed for Ni2FeSi and Co2FeSi, respectively. Meanwhile, a well-defined, ordered L21 type was observed for Co2MnSi GCMWs. The change in the positions of Ni, Co and Mn, Fe in X2YSi resulted in a variation in the lattice cell parameters and average grain size of the sample. The room-temperature magnetic behavior showed a dramatic change depending on the chemical composition, where Ni2FeSi MWs showed the highest coercivity (Hc) compared to Co2FeSi and Co2MnSi MWs. The Hc value of Ni2FeSi MWs was 16 times higher than that of Co2MnSi MWs and 3 times higher than that of Co2FeSi MWs. Meanwhile, the highest reduced remanence was reported for Co2FeSi MWs (Mr = 0.92), being about 0.82 and 0.22 for Ni2FeSi and Co2MnSi MWs, respectively. From the analysis of the temperature dependence of the magnetic properties (Hc and Mr) of X2YZ MWs, we deduced that the Hc showed a stable tendency for Co2MnSi and Co2FeSi MWs. Meanwhile, two flipped points were observed for Ni2FeSi MWs, where the behavior of Hc changed with temperature. For Mr, a monotonic increase on decreasing the temperature was observed for Co2FeSi and Ni2FeSi MWs, and it remained roughly stable for Co2MnSi MWs. The thermomagnetic curves at low magnetic field showed irreversible magnetic behavior for Co2MnSi and Co2FeSi MWs and regular ferromagnetic behavior for Ni2FeSi MWs. The current result illustrates the ability to tailor the structure and magnetic behavior of X2YZ MWs at fixed geometric parameters. Additionally, a different behavior was revealed in X2YZ MWs depending on the degree of ordering and element distribution. The tunability of the magnetic properties of X2YZ MWs makes them suitable for sensing applications.

This present study illustrates the strong effect of geometrical parameters on the magneto-structural properties of Co2MnSi glass-coated microwires prepared using the Taylor–Ulitovsky method. Thus, there are three samples with different geometrical aspect ratios (ρ). The XRD analysis shows a significant change by modifying the aspect ratio; for ρ = 0.42, the main peak with miller indices (220) is recognized as an A2-type disordered cubic structure. For the sample with ρ = 0.46, mixed L21 and B2 cubic structures are observed. Meanwhile, in the sample with a low aspect ratio, ρ = 0.30, the perfect L21 ordered cubic structure is attained. Magnetic characterization has been carried out at a wide range of temperatures and magnetic fields. A significant increase in coercivity and normalized reduced remanence by decreasing the aspect ratio is detected. The change in the magnetic properties is attributed to the modification in the microstructure, which is induced during the fabrication process. Such a dependence on the microstructure and magnetic properties on the ρ-ratio can be associated either with the internal stress distribution and magnitude or with different quenching rates of microwires with different aspect ratios. The current findings demonstrate the tunability of the microstructure and magnetic properties of Co2MnSi-glass-coated microwires simply via a small modification in the geometric properties during the manufacturing process and without excreting any additional post-processing. The variation in the geometric parameters of Co2MnSi glass-coated microwires allows us to tune the magnetic properties and structure, which is essentially advantageous for sensing device development.

We studied the magnetostriction coefficients, λs, Curie temperature, Tc, and their dependence on annealing conditions in Fe47Ni27Si11B13C2 and Co67Fe3.9Ni1.5B11.5Si14.5Mo1.6 amorphous glass-coated microwires with rather different character of hysteresis loops. A positive λs ≈ 20 × 10−6 is observed in as-prepared Fe47Ni27Si11B13C2, while low and negative λs ≈ −0.3 × 10−6 is obtained for Co67Fe3.9Ni1.5B11.5Si14.5Mo1.6 microwire. Annealing affects the magnetostriction coefficients and Curie temperatures, Tc, of both Fe47Ni27Si11B13C2 and Co67Fe3.9Ni1.5B11.5Si14.5Mo1.6 glass-coated microwires in a similar way. Observed dependencies of hysteresis loops, λs and Tc on annealing conditions are discussed in terms of superposition of internal stresses relaxation and structural relaxation of studied microwires. We observed linear λs dependence on applied stress, σ, in both studied microwires. A decrease in the magnetostriction coefficient upon applied stress is observed for Co-rich microwires with low and negative magnetostriction coefficient. On the contrary, for Fe-Ni-rich microwires with a positive magnetostriction coefficient, an increase in the magnetostriction coefficient with applied stress is observed. The observed results are discussed considering the internal stresses relaxation and short range atomic rearrangements induced by annealing on hysteresis loops, magnetostriction coefficients and Curie temperatures of studied microwires.

In this article, we study the effect of annealing temperature and applied stress on the magnetic properties of Fe71.80B13.27Si11.02Nb2.99Ni0.92 and Co65.34Si12.00B10.20Cr8.48Fe3.90Mo0.08 microwires. An anomalous behavior of the coercive field is observed while applying stress, indicating nontrivial changes in the microwire magnetic anisotropy. The effect of applied stimuli on the magnetic anisotropy and magnetostriction constant in both microwires is also discussed.

In this article, we studied the effect of annealing (600 °C for 1 h) and the applied magnetic field from 50 Oe to 20 kOe of Co2FeSi glass-coated microwires with ordered L21 structure prepared by Taylor–Ulitovsky technique on the magnetic behavior. The as-prepared and annealed samples show a ferromagnetic behavior at the range of measuring temperature (5 to 400 K) and magnetic field (50 Oe to 20 kOe). M–H loops of as prepared sample do not show a squared shape. Meanwhile, perfectly squared hysteresis loops have detected for the annealed sample. In addition, annealed sample shows high magnetization M/M5K ratio, coercivity, and anisotropy field, as-compared to the as-prepared one. The annealed sample shows considerable irreversibility when the magnetic behavior changes with temperature upon the applied magnetic field at 50 and 200 Oe. Such irreversibility does not found in the as-prepared sample measured at the same magnetic field due to mixed amorphous and crystalline structure. By increasing the external magnetic field higher than 200 Oe and up to 20 kOe a gradual changing in the magnetic behavior has been detected where the irreversibility disappeared at applying magnetic field about 1 kOe and the magnetic behavior is totally change by increasing the external magnetic field up to the maximum 20 kOe. The difference in the magnetic behavior of the annealed glass-coated Co2FeSi glass-coated microwires indicates the effect of internal stresses induced by the presence of the glass-coating and the annealing-induced recrystallization.

Giant magnetoimpedance, GMI, effect and magnetic properties upon temperature influence of as-prepared and stress-annealed amorphous Fe75B9Si12C4 glass-coated microwires produced by the Taylor-Ulitovsky technique are analyzed. Remarkable change in the hysteresis loops and GMI effect is observed for both samples upon heating. Tuning of the stress-annealing conditions allows one to vary the temperature dependence. Furthermore, it is observed almost complete reversibility of the changes induced by the temperature. Observed dependences are explained by the heating effect on the internal stresses relaxation, by the modification of the thermal expansion coefficients of the metallic nucleus and the glass coating, and by the Hopkinson effect.

The influence of a ferromagnetic cover layer on giant magnetoimpedance (GMI) effect in nearly-zero magnetostrictive Co66.5Fe3.5Si12.0B18.0 amorphous ribbon after being surface coated by an electrodeposited Co layer of 10 μm in thickness, has been studied in the high frequency range between 10 MHz and 1.5 GHz. Longitudinal MOKE measurements performed on both kind of samples reveal the influence of exchange coupling interaction at the interface between the magnetic amorphous ribbon and electrodeposited Co coating layer, which is sensitive to the skin depth effect at high ac current frequency values. Comparison between GMI responses of the Co coated amorphous ribbon and the as-cast sample is provided. A more sharp and well defined double-peaks dependence of impedance on magnetic field, but with lower peaks intensity, is observed for the Co coated ribbon in the frequency range of 10–100 MHz, while the peaks intensity is higher than that observed in the as-cast ribbon at the high frequency value of 1 GHz due to the higher resistance of the Co electroplated layer than the core one. The influence of a dc bias drive current on the GMI response in both amorphous ribbons (as-cast and Co layered) is analyzed, which originates the removal of magnetic domain structure from both, the as-cast and Co-coated ribbons, giving rise more sensitive GMI effect. CoFeSiB amorphous ribbon with vanishing magnetostriction can achieve improved high frequency magnetic properties after being surface coated with electrodeposited ferromagnetic layers, as outstanding candidates for electromagnetic and magnetomechanical engineering applications.

Objective – obtaining and characterization of hybrid cell lines producing monoclonal antibodies against I and II types of shiga-like toxins.Materials and methods. Shiga-like toxins obtained in “48thCentral Research Institute” of Ministry of Defense of Russian Federation (Kirov), BALB/c mice, myeloma cells SP2/0-Ag14 were used in research. Immune splenocytes and SP2/0-Ag14 myeloma cells were fused according to G. Kohler and C. Milstein method in De St. Fazekas and D. Scheidegger modifcation using 50 % polyethylene glycol. Hybrid cell lines producing specifc monoclonal antibodies were cloned by limited dilutions. Hybridomas growth and producing properties were studied in vitro and in vivo. Specifc activity of immune sera, culture and ascitic fluids were studied by indirect ELISA. Monoclonal antibodies from ascitic fluids were precipitated by saturated ammonium sulfate, followed by ion exchange chromatographyResults and discussion. 8 hybridomas producing monoclonal antibodies against I and II types shiga-like toxins were obtained. Hybridomas are characterized by stable proliferation and antibody-producing activity during 10 passages in vitro and 3 passages in vivo (observation period). Obtained monoclonal antibodies can be used for ELISA detection of I and II types shiga-like toxins. Minimum detectable concentration of shiga-like toxins in sandwich ELISA is 1 ng/ml. The possibility of detecting shiga-like toxins without typical differentiation was shown when using in the enzyme immunoassay a polyreceptor mixture of monoclonal antibodies for sensitizing the plate and a polyspecifc mixture of immunoperoxidase conjugates.

As-prepared Fe-rich microwires with perfectly rectangular hysteresis loops present magnetization reversal through fast domain wall propagation, while the giant magnetoimpedance (GMI) effect in Fe-rich microwires is rather low. However, the lower cost of Fe-rich microwires makes them attractive for magnetic sensors applications. We studied the effect of conventional (furnace) annealing and Joule heating on magnetic-propertied domain wall (DW) dynamics and the GMI effect in two Fe microwires with different geometries. We observed that magnetic softness, GMI effect and domain wall (DW) dynamics can be substantially improved by appropriate annealing. Observed experimental results are discussed considering the counterbalance between the internal stresses relaxation and induced magnetic anisotropy associated with the presence of an Oersted magnetic field during Joule heating.

In the current work, we illustrate the effect of adding a small amount of carbon to very common Co2MnSi Heusler alloy-based glass-coated microwires. A significant change in the magnetic and structure structural properties was observed for the new alloy Co2MnSiC compared to the Co2MnSi alloy. Magneto-structural investigations were performed to clarify the main physical parameters, i.e., structural and magnetic parameters, at a wide range of measuring temperatures. The XRD analysis illustrated the well-defined crystalline structure with average grain size (Dg = 29.16 nm) and a uniform cubic structure with A2 type compared to the mixed L21 and B2 cubic structures for Co2MnSi-based glass-coated microwires. The magnetic behavior was investigated at a temperature range of 5 to 300 K and under an applied external magnetic field (50 Oe to 20 kOe). The thermomagnetic behavior of Co2MnSiC glass-coated microwires shows a perfectly stable behavior for a temperature range from 300 K to 5 K. By studying the field cooling (FC) and field heating (FH) magnetization curves at a wide range of applied external magnetic fields, we detected a critical magnetic field (H = 1 kOe) where FC and FH curves have a stable magnetic behavior for the Co2MnSiC sample; such stability was not found in the Co2MnSi sample. We proposed a phenomenal expression to estimate the magnetization thermal stability, ΔM (%), of FC and FH magnetization curves, and the maximum value was detected at the critical magnetic field where ΔM (%) ≈ 98%. The promising magnetic stability of Co2MnSiC glass-coated microwires with temperature is due to the changing of the microstructure induced by the addition of carbon, as the A2-type structure shows a unique stability in response to variation in the temperature and the external magnetic field. In addition, a unique internal mechanical stress was induced during the fabrication process and played a role in controlling magnetic behavior with the temperature and external magnetic field. The obtained results make Co2MnSiC a promising candidate for magnetic sensing devices based on Heusler glass-coated microwires.

Objective of the study was the development of experimental ELISA tests and lateral flow immunoassays for detection of staphylococcal enterotoxins, A and B types.Materials and methods. Hybridomas, producing monoclonal antibodies against staphylococcal enterotoxins A and B from State Collection of the Affiliated Branch of the “48th Central Research Institute” of the Ministry of Defense of the Russian Federation, BALB/c mice and staphylococcal enterotoxins A and B were used in the research. Hybridoma cells were incubated in culture flasks and in the peritoneal cavity of BALB/c mice. Monoclonal antibodies were isolated from ascitic fluids through precipitation with saturated ammonium sulfate subsequently purified using ion-exchange chromatography. Obtained preparations of monoclonal antibodies were used for the construction of ELISA tests and immune-chromatographic reagent panels for the detection of staphylococcal enterotoxins A and B. Specific components of ELISA tests were lyophilized in protective media.Results and discussion. ELISA tests and lateral flow immunoassays which allow for detecting staphylococcal enterotoxins A and B at concentrations of 0.5 ng/ml and higher, including in food samples, have been constructed.