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The results of simulating of a rolling process and selecting the optimal deformation conditions and the QForm software package are used to develop a technology for manufacturing ring workpieces with an outer diameter of 660 mm made of an intermetallic orthorhombic VIT1 titanium alloy. The conditions of heat treatment of the VIT1 alloy ring workpiece are selected. The structure of the ring workpiece in various directions and the mechanical properties of the ring workpiece material are comprehensively studied. The strength characteristics are found to be at a satisfactory level. A sample of the bling guide of a high-pressure compressor is made for the first time from an orthorhombic VIT1 alloy.

The conclusion of the generating equipment for repair, in the optimal way, is the main one when planning repairs. But to consider this issue, it is necessary to understand the essence of the problem and find ways to solve the identified problem. It is necessary to start with the concept of "reliability", namely the reliability of electrical power systems. The article deals with power systems in general, properties of power systems, elements of power systems. The ratio of the functions and properties of energy systems is analyzed, where the main functions of the objects under consideration are: a function associated with the purpose of production equipment, a function associated with the fact of its creation. The meaning of the assignment function is that the object has some task that is performed. In turn, the fulfillment or non-fulfillment of the task is directly related to reliability. Reliability is the property of an object to perform a specified function related to its purpose, subject to specified constraints.

This work is an experimental justification of the choice of the temperature and time modes designed for the heat treatment of real magnetrons, the end result of which is the initial decomposition of barium carbonate into barium oxide. We experimentally determine the temperatures of polymorphic transitions in barium carbonate and the temperature of the dissociation of barium carbonate in different atmospheres (air, argon, carbon dioxide, and vacuum) for the physical modeling of the processes occurring in pumped magnetrons. The phase composition of a test barium carbonate specimen is determined at room temperature by X-ray phase analysis (XPA) on a diffractometer before and after heating. The effect of the temperature and time of isothermal exposure on the phase composition is experimentally investigated on a high-temperature diffractometer. Using a derivatograph, we analyze the chemical and physicochemical processes that occur in the samples during heating. The enthalpy of polymorphic transitions and the activation energy of dissociation are evaluated. Quantitative data are presented that characterize the kinetics of phase transitions for various heat treatment modes and demonstrate the temperature ranges of the existence of different phases. It is shown that reducing the heating rate and increasing the time of heating interruptions slow down the transition of BaCO3 into BaO. It is established that the powder is sintered when heating barium carbonate.

The article presents a study of the state of the real estate market in the context of the new coronavirus infection “CoVid-19”. The influence of the pandemic on this market is shown on the example of one of the subjects of the Russian Federation - the Irkutsk region. A solution has been proposed for the efficient operation of enterprises in the conditions of a recession in the construction of real estate, which consists in reimbursing the lease of real estate to small and medium-sized enterprises on certain conditions. Preliminary calculations have been carried out, which have shown the effectiveness of the reimbursement of rental space to enterprises. The basis for such calculations was the concept of increasing tax profits obtained from deductions from enterprises to the regional and federal budgets. The conditions that the company must accept as obligations in case of a positive decision regarding the reimbursement of rent payments from the regional budget are given. Eight indicators have been identified that give a definite economic effect to the regional budget. The conclusion is made about the expediency of reimbursing rent payments to small and medium-sized businesses.

Diamond is unique material that have long been known to humanity. It has extra high hardness, thermal conductivity, as well as unique electrophysical characteristics that can be managed by changing its impurity composition. Therefore, this material has gained the potential of widespread use in engineering, which is currently complicated by the high cost of diamonds, difficulties of its synthesis, mechanical and physical processing. A promising direction for obtaining high-quality poly- and single crystals and, accordingly, expanding the areas of diamond use is the method of its deposition from the gas phase (CVD). The main problem that researchers face during deposition the diamond is the formation of surface defects in the growth zone. In this work, we discuss defects observed on single-crystal diamond CVD-films of 300-500 μm thick obtained from methane-hydrogen plasma with 3% methane. The surface was studied by scanning electron microscopy. As a result of the work, we revealed that during the diamond films CVD-growth mainly three types of defects are formed: etch pits, isolated diamond particles (“straying” diamonds) and coarse-grained diamond formed along the diamond plates periphery. Methods for eliminating these defects are proposed.

Molecular mechanisms underlying the formation of B-cell lymphomas in connection with processes associated with the maturation of B-lymphocytes are reviewed. The currently used diagnostic methods do not always distinguish lymphomas from reactive changes of the lymphoid tissue. The principle of the molecular genetic method of clonality detection in lymphocyte populations, technical problems, and the strategy of its application in clinical diagnostics of lymphomas are described in detail.

Glutamatergic neurotransmission is believed to be critically involved in the acquisition and maintenance of drug addiction. The present study evaluated the role of metabotropic glutamate (mGlu) 1 receptors in the reinstatement of nicotine-seeking behavior. Rats were trained to nose-poke to receive response-contingent intravenous infusions of nicotine (0.01 mg/kg/infusion, free base). Following the subsequent extinction phase, reinstatement tests were conducted in animals that were exposed either to response-contingent presentations of the nicotine-associated discrete light cues or to non-contingent nicotine priming injection (0.3mg/kg, s.c., salt) just prior to the test session. In a separate experiment, rats were subjected to the nearly identical response-reinstatement procedure but operant responding was established using food pellets instead of nicotine infusions. Pretreatment with the mGlu1 receptor antagonist EMQMCM (JNJ16567083, (3-ethyl-2-methyl-quinolin-6-yl)-(4-methoxy-cyclohexyl)-methanone methanesulfonate) significantly inhibited cue-induced reinstatement of nicotine-seeking behavior (5 and 10, but not 2.5 mg/kg). EMQMCM (5 mg/kg) also prevented nicotine priming-induced reinstatement of nicotine-seeking behavior. At the highest tested dose only (10 mg/kg), EMQMCM attenuated cue-induced reinstatement of food-seeking behavior. Taken together with the previous reports, the present findings further suggest that blockade of mGlu1 receptors may be beneficial for preventing relapse to tobacco smoking in nicotine-dependent individuals.

Previous studies suggested that metabotropic glutamate 5 (mGlu5) receptors play an important role in the reinforcing effects of abused drugs. The present experiments evaluated the effects of the mGlu5 receptor antagonist, MPEP (2-methyl-6-(phenylethynyl)-pyridine hydrochloride; 1–10 mg/kg, salt, i.p.), in rat models of nicotine-seeking behavior that may have relevance to relapse to drug-taking. Male Wistar rats (with restricted access to food) were trained to nose-poke to receive intravenous infusions of nicotine (0.03 mg/kg per infusion, base) under a fixed ratio 5 time out 60 s schedule of reinforcement. After stable nicotine self-administration was acquired, nose-poking behavior was extinguished in the absence of nicotine-associated cues. During the reinstatement test phase, independent groups of animals were exposed to: (a) response-contingent nicotine-associated cues (cue-induced reinstatement); or (b) response-noncontingent presentations of 45-mg food pellets under fixed time 2 min schedule (schedule-induced reinstatement). Additional control experiments were conducted to demonstrate that in nicotine-naive animals MPEP does not affect cue-induced reinstatement of food-seeking behavior and has no effects on operant behavior maintained by a simple fixed interval 2 min schedule of food reinforcement. Pretreatment with MPEP (10 mg/kg) significantly attenuated the reinstatement of nicotine-seeking in both experiments. Further, MPEP (10 mg/kg) significantly attenuated polydipsia induced by a fixed time 2 min food schedule. In conclusion, the present findings indicate that the blockade of mGlu5 receptors attenuates cue-induced reinstatement of nicotine self-administration behavior (but not food-seeking) and may produce a general inhibition of schedule-induced behaviors, including schedule-induced nicotine-seeking.

Several drugs, such as N-methyl-D-aspartate (NMDA) receptor channel blockers (memantine), naltrexone (but not naloxone) and acamprosate, have previously been reported to attenuate the expression of the alcohol deprivation effect, a phenomenon seen as an increase in post-deprivation alcohol consumption. The present study aimed to evaluate the effects of these drugs on the development and expression of the saccharin deprivation effect in adult male Wistar rats. Memantine (13 mg/kg per day) and naltrexone (5 mg/kg, twice daily), but not naloxone (24 mg/kg per day) or acamprosate (200 mg/kg, twice daily), prevented the increase in the consumption of saccharin after a 1-week deprivation from free-choice, unlimited access to saccharin (0.1%, w/v). Taken together with the results of previous studies, these results suggest that naltrexone and memantine attenuate the expression of both the alcohol and saccharin deprivation effects.

N-Methyl-D-aspartate (NMDA) receptor blockade enhances motor activity and stimulates dopamine metabolism, effects shared with classical psychostimulant drugs. The present study aimed to characterize behavioral effects of two NMDA receptor channel blockers, MK-801 and memantine, in both Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. In Experiment 1, SHR rats demonstrated higher spontaneous locomotor activity and spent more time in the central area of the open field apparatus compared with WKY rats. Rats of both strains pre-treated with MK-801 (0.01-0.3 mg/kg) or memantine (1-32 mg/kg) demonstrated dose-dependent increases in the total distance traveled and time spent in the central area. Experiment 2 was based on the two-lever discrete-trial delayed reinforcement task in which rats could press one lever to obtain one pellet immediately or another lever for four pellets delivered after a variable delay (0-60 s). Tolerance to delay of reward did not differ between strains. MK-801 (0.03-0.3 mg/kg) and memantine (1-10 mg/kg) produced small, but significant, facilitation of the large-reward lever responding and markedly impaired operant performance at higher dose levels (increased number of missed trials). For both experiments, effects of MK-801 and memantine were more pronounced in WKY compared with SHR rats. Additional studies are needed to address the utility of noncompetitive NMDA receptor blockers in the treatment of attention deficit and hyperactivity disorder.

Drill bits of the cutting type over the period of their existence have undergone significant changes – from the use of carbide cutters to diamond composite PDC elements, in which the diamond layer is applied to a hardmetal substrate. Using such elements, it was possible to significantly increase the service life of the drill bits, however, during work, there is a significant abrasive deterioration of the bit body, which does not fully realize the advantages of PDC elements. Therefore, to protect the body from wear use special wear-resistant coatings. This work is devoted to research of microstructural coatings, namely coatings brands WokaDur NiA, HR-6750, HR-6750 with sublayer Rock Dur 47 on various steel substrates which applied by the gas-thermal spraying in Ltd "Oerlikon Metko Rus". They were examined with the use of scanning electron microscopy, X-ray phase analysis and a Vickers micro-hardness tester. It was established that the microhardness of the coating matrix is 590–660 HV, and the microhardness of tungsten carbide particles reinforcing the coating, is 2145–2455 HV.

Modern drill bits have high abrasive wear in the area of contact with the rock and removed sludge. Currently, these bits have a protective layer on the bit body, which consists of a metal matrix with inclusions of carbide particles. The research matrix of this coating and the wear-resistant particles is a prerequisite in the design and production of drill bits. In this work, complex investigation was made for various carbide powders of the grades Relit (tungsten carbide produced by Ltd "ROSNAMIS") which are used as wear-resistant particles in the coating of the drill bit body. The morphology and phase composition of the chosen powders as well as the influence of a particle shape on prospects of their application in wear-resistance coating presented in this work.

It is known that modern drilling bit body undergoes significant abrasive wear in the contact area with the solid and the retracted cuttings. For protection of the body rationally use wear-resistant coating, which is welded directly to the body of bit. Before mass use of the developed coverings they need to be investigated by various methods that it was possible to characterize coatings and on the basis of the obtained data to perform optimization of both composition of coatings and technology. Such methods include microstructural studies tribological tests, crack resistance and others. This work is devoted to the tribological tests of imported brand of coatings WokaDur NiA and and domestic brand of coating HR-6750 (both brands manufactured by Ltd "Oerlikon Metco Rus"), used to protect the bit body from abrasive wear.

Using the bovine αS1-casein gene, a genetic construct with an endostatin-coding fragment of the mouse collagen XVIII cDNA was designed to express endostatin in milk of transgenic animals. Several transgenic mice were obtained. The mice secreted endostatin in milk at 70–300 ng/μl and transmitted this character to their progeny.

The in situ Hall effect measurements at room temperature showed that formation of the atomically clean Si(111) 7×7 surface as a result of high-temperature annealing (T=1250°C, t=120–180 s) of n-Si reverses the majority carrier sign at the surface, and a hole-enriched layer is formed at the p-Si surface. The different dynamics of Hall and resistivity voltage variations within the first monolayer of iron adsorbed onto substrates with a p-n junction or with a hole-enriched layer is not related to conduction over the adsorbed layer. Conduction in the Fe layer of thickness exceeding three monolayers is caused in both cases by the transport of electrons with densities 2×1013–2×1014 cm−2 and mobilities 65–90 cm2/(V s).

By the method of in situ Hall effect measurements at room temperature, it was shown that the formation of a clean Si (111)(7×7) surface at high temperature annealing (T=1250°, t=120–180 s) of n-type conductivity silicon results in a change of the majority carriers on a surface. But on a surface of p-type conductivity silicon it results in the formation of a hole accumulated layer. Various dynamics of changes in the Hall voltage and resistivity voltage within the limits of the first monolayer of room temperature adsorption of iron and chromium on substrates with a p–n junction and with a hole accumulated layer are not connected with conductivity along an absorbed layer. To understand the mechanism of conductivity in a system adsorbed layer Fe(Cr)/ Si (111)(7×7), it is necessary to take into account two effects: (a) destruction of the superstructure Si (111)(7×7); (b) formation of donor-type surface states of Fe(Cr) in the band gap of silicon. Destruction of the localized surface states of the superstructure Si (111)(7×7) plays the greatest role, when the density of donor-type surface states is very small. It corresponds to adsorption of Cr on Si (111) of p-type conductivity. The greatest contribution of donor-type surface states to the conductivity of the surface space-charge layer was observed with adsorption of Fe on Si (111) of n-type conductivity. Conductivity through the adsorbed iron (chromium) layer began with a thickness more than three monolayers.

Cancer-testis (CT) antigens are normally expressed mostly in human germ cells, there is also an aberrant expression in some tumor cells. This expression profile makes them potential tumor growth biomarkers and a promising target for tumor immunotherapy. Specificity of CT genes expression in oral malignant and potentially malignant diseases, e.g. oral leukoplakia, is not yet studied. Data on CT genes expression profile in leukoplakia would allow developing new diagnostic methods with potential value for immunotherapy and prophylaxis of leukoplakia malignization. In our study we compared CT genes expression in normal oral mucosa, oral leukoplakia and oral squamous cell carcinoma. We are the first to describe CT genes expression in oral leukoplakia without dysplasia. This findings make impossible differential diagnosis of oral leukoplakia and squamous cell carcinoma on the basis of CT genes expression. The prognostic value of CT genes expression is still unclear, therefore the longitudinal studies are necessary.

Molecular mechanisms underlying the formation of B-cell lymphomas in connection with processes associated with the maturation of B lymphocytes are reviewed. The currently used diagnostic methods do not always distinguish lymphomas from reactive changes of the lymphoid tissue. The principle of the molecular genetic method ofclonality detection in lymphocyte populations, technical problems, and the strategy of its application in clinical diagnostics of lymphomas are described in detail.

The regulatory region of the bovine alphaS1 casein gene was used to obtain two genetic constructs for expression of human lactoferrin in the mammary gland of transgenic animals. Several transfected mouse embryonic stem cell (ESC) lines and primary transgenic mice were generated with these constructs. Recombinant lactoferrin was not detected in milk of transgenic mice by Western blotting. However, a recombinant transcript was found in RNAs isolated from mammary glands of transgenic females during lactation and from transfected ESC lines.

Antagonists acting at the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors inhibit various phenomena associated with exposures to nicotine (e.g., tolerance, sensitization, dependence, and intravenous self-administration). These effects are often discussed in terms of nicotine-induced glutamate release with subsequent glutamate-dependent stimulation of dopamine metabolism and neuronal plasticity in brain areas critically involved in drug-addiction mechanisms. However, it is also well established that certain types of NMDA receptor antagonists (channel blockers) potently bind to nicotinic receptors and may act as nicotinic receptor antagonists.The present study aimed to evaluate the discriminative-stimulus effects of the NMDA receptor channel blockers (+)MK-801, dextromethorphan, and memantine in rats trained to discriminate nicotine from its vehicle.Adult male Wistar rats were trained to discriminate 0.6 mg/kg nicotine from saline under a two-lever, fixed-ratio 10 schedule of food reinforcement. During test sessions, injections of (+)MK-801 (0.03--0.3 mg/kg, i.p.), dextromethorphan (30 mg/kg, s.c.), or memantine (1--10 mg/kg, i.p.) were co-administered with s.c. nicotine (0.075--0.6 mg/kg; interaction tests) or saline (generalization tests). Additional interaction and generalization tests were conducted with the selective nicotinic receptor antagonists mecamylamine (0.1--3 mg/kg, s.c.) and MRZ 2/621 (0.3--10 mg/kg, i.p.), and the mGlu5 receptor antagonist MPEP (3--10 mg/kg, i.p.).In generalization tests, none of the compounds produced any appreciable levels of substitution for nicotine. The nicotine discriminative-stimulus control was dose dependently attenuated by mecamylamine (ED(50)=0.67 mg/kg) and MRZ 2/621 (ED(50)=9.7 mg/kg). Both agents produced a marked downward shift in the nicotine dose-response curve. Memantine and MPEP slightly attenuated nicotine discriminative-stimulus effects, while (+)MK-801 and dextromethorphan did not affect the nicotine-appropriate responding.NMDA receptor channel blockers, such as (+)MK-801, dextromethorphan, and memantine, have minimal interactions with the discriminative-stimulus effects of nicotine.

To evaluate efficacy and tolerance of glivek in chronic myeloid leukemia (CML) in patients who failed interferon-alpha (If-a) preparations.79 patients in a chronic phase of Ph + CML with hematological and cytogenetic resistance or intolerance of If-a. The response to glivec was assessed by achievement of a complete hematological remission and the cytogenetic effect (the degree of reduction of cell clone Ph+ in bone marrow). Tolerance and safety of the drug was studied by monthly standard clinicohematological tests.Not only a hematological remission (92.4%), but also partial (46.8%) or complete (27.8%) elimination of BCR-ABL +/- cells were achieved after 12 months of the treatment. Glivec was well tolerated. Hematological toxicity primarily as neutropenia and thrombocytopenia were observed in 54.4 and 42% patients, respectively. Neutropenia of the third degree which made impossible to continue the treatment was observed in 29.1% patients; throbocytopenia of the third degree was registered in 16.5% patients. Among most frequent non-hematological side effects there were moderate edema, nausea, leg muscle convulsions, weight gain, arthralgias, skin eruption. All the complications were transient, were managed in all cases with only a short-time discontinuation of glivec therapy.High activity of glivec at early stages of CML allows using this drug as a first-line therapy in patients with CML.

Using the bovine alpha S1-casein gene, a genetic construct with an endostatin-coding fragment of the mouse collagen XVIII cDNA was designed to express endostatin in milk of transgenic animals. Several transgenic mice were obtained. The mice secreted endostatin in milk at 70-300 ng/microliter and transmitted this character to their progeny.

To evaluate the prognostic significance of P-glycoprotein (Pgp) in chronic myeloid leukemia (CML).Functional activity (rhodamine 123 test) and expression of Pgp (binding of UIC2 monoclonal antibodies by cells) were evaluated by flow cytofluorometry. A total of 141 samples of peripheral blood from 121 patients with various stages of CML were examined.The number of patients whose cells express functionally active Pgp increases during the blast crisis (BC) in comparison with the chronic phase (CP). Repeated testing of patients with BC and CP showed that Pgp-expressing cells can disappear from the peripheral blood of patients despite the treatment by Pgp preparations and substrates. However the number of cases with expression and functional activity of Pgp increases in the course of BC. Several patients in whom functionally active Pgp was not detected during diagnosis of BC had longer BC phase than patients with the active protein.These data suggest that active Pgp contributes to CML BC (presumably to patient's response to therapy) but this contribution is not decisive.

To control safety and efficiency of therapeutic plasmapheresis (PA) by osmolality, colloido-osmotic pressure (COP), total protein concentration before and after the procedure in patients with paraproteinemic hemoblastosis.20 patients with multiple myeloma have undergone 42 PA procedures conducted by two techniques: continuous flow centrifugation on blood fractioners or intermittent centrifugation of blood in plastic containers. The removed plasma volume averaged 1/3 (group 1) or 2/3 of the plasma volume (group 2). The removed protein reached 62-197 g. Isotonic sodium chloride solution and/or reopolyglucin (20-60 g) replaced the removed plasm. Total protein concentration was measured colorimetrically in biuretic reaction, plasma osmolality--cryoscopically and COP--on Knauer osmometer.PA leads to a short decline in osmolality (97.0-99.1%), of total protein concentration (82.8-78.6%) and of COD (79.2% in replacement with saline and 90.2% in replacement with dextran). During recovery after the procedure plasma osmotic activity and protein concentration return to the baseline.In elimination of 1/3 of plasma volume and crystalloid infusion, hemodilution promotes release of abnormal proteins from the tissues into the circulation and thereafter removal them from the organism. In removal of 1/2 and more of plasma volume, COP demans correction made by administration of colloids, e.g. solution of low molecular dextran. There is a potential danger of COD lowering several hours after PA due to different speed of dextran elimination and mobilization of protein reserve.

A secreted beta-galactosidase gene from P. canescens was cloned using synthetic oligonucleotide probes and its nucleotide sequence was partially determined. The gene was shown to be present in the genome as a single copy. The deduced primary structure of the signal peptide and the first 25 amino acid residues of the mature protein was established. The structure analysis of the beta-galactosidase gene revealed at least one short intron 64 bp long. The transcription start point was found to be located 89 bp upstream the initiation codon. Some peculiarities of the signal peptide cleavage mechanism are discussed.

Prolactin coding mRNA was shown to be a prevalent part of chum salmon (Oncorhynchus keta) pituitary poly(A)-RNA during the spawning period. Clone lambda gtPrk12 was selected from the pituitary cDNA library by means of hybridization with the prolactin probe, and a nucleotide sequence of the insertion was determined and compared to the prolactin coding sequences from rainbow trout and Pacific chinook salmon, which had been published earlier. The sequences compared exhibited a significant homology. The deduced amino acid sequence of the chum salmon prolactin differed from a sequence determined directly in a single position. The prolactin-coding sequence can be used for constructing the bacterial strain producing prolactin.

Several cDNA cloned which code for subfamily A3 subunits (A3B4 and A5A4B3) of soybean storage protein glycinin were analysed by means of restriction mapping and hybrid - selection. The comparison of A3B4 and A5A4B3 subunits cDNA sequences reveals the 90% homology. The nucleotide sequences obtained in the process of this work were compared with those reported about elsewhere, in order to study the interaspecific variability of homologous but not identical storage protein genes of subfamily A3 glycinin subunit. Nucleotide replacements were found to occur 6 times more frequently in A3B4 subunit gene, as compared to A5A4B3 subunit gene (48 replacements against 8).

Nucleotide sequences of cDNAs encoding soybean glycinin B4 polypeptide were compared in three soybean cultivars and two plant introductions of wild soybean Glycine soja. Only two nucleotide substitutions were found in three cultivars G. max, as compared with G. max and G. soja having nucleotide sequences which contain four nucleotide substitutions. These data serve as additional evidence, at molecular level, indicating the origin of G. max from G. soja. On the other hand, the time period required for four nucleotide substitutions' accumulation, as calculated from parameters of molecular evolution of 11S globulins, is much longer than the term having passed after soybean domestication.

Nucleotide sequences of cloned cDNA coding for soybean storage protein glycinin and deduced amino acid sequences of basic polypeptides (subfamily II) of glycinin are compared with the amino acid sequences of 11S globulins from other plants. An average number of amino acid substitutions in various evolutionary branches is calculated. A proportional dependence is established between the average number of substitutions per site (the evolutionary distance) and the hypothetical term of divergence of corresponding taxa. The evolution rate of 11S globulins and a term of divergence of the two subfamilies of 11S globulin polypeptides in Fabaceae is estimated.