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1. In the manufacture of VKA-1 composite material the diffusion welding of the semifinished product is accompanied by the formation at the fiber/matrix interfaces of the AlB2 phase in the form of spherical inclusions at sites of Al2O3 film disintegration on the matrix foils. 2. To each diffusion welding temperature there corresponds a certain period of time during which no AlB2 phase is formed at the fiber/matrix interfaces. 3. A method of assessing the defectiveness of the surfaces of reinforcing fibers is described, which can be effectively employed for studying the reaction in the CM, particularly its early stages.

The effects of hypertonic solutions and slow freezing to different temperatures in the range of 0 to -80 degrees C on the permeability of plasma membranes of reconstituted erythrocytes were investigated. It has been found that even increased concentrations of NaCl or KCl (1.2 to 4.2 M) do not change appreciably release of K+, [14C]sucrose and haemoglobin (by 8 to 20%), while leakage of markers into the supernatant fluid is essentially completed on freezing to -25 degrees C. If the content of mobile water in the sample of reconstituted erythrocytes is lower than 1 to 2%, the permeability of plasma membranes for [14C]sucrose and haemoglobin changes after freezing to -19 to -22 degrees C. These findings suggest that the existence of water-dependent structural changes in the membranes can be responsible for a primary mechanism of altering the permeability at low temperatures.

The experiments on ICRF heating in the Tokamak 'TUMAN-3' were carried out with one all-metal antenna located on the low field side of the torus. The antenna excited the wide K/sub /// spectrum (0-0.15 cm-1). The scenarios of experiments covered both the cases with a small fraction of hydrogen in a deuterium plasma, like in the experiments at the PLT Tokamak (Hosea et al., Proc. 12th ECCFPP, Budapest, vol.2, p.120, 1985), and the cases with a large amount of hydrogen, which are thoroughly investigated in TFR (TFR Group, Plasma Physics and Controlled Fusion Research, Vienna, IAEA, vol.2, p.17 1983).

Effluent containing clay and chamotte can be treated satisfactorily in a clarifier with a suspended layer of sediment. The content of suspended matter in the clarified effluent does not exceed 13 mg/liter. The flow velocity in the suspended layer and the concentration of the layer do not vary with the original concentration (within the investigated limits) of the solid phase in the effluent but depend on the height of the suspended layer and the physicochemical properties of the suspension. The sediment produced in the clarification of the effluent is readily dehydrated.

With vacuum filtration the following apply: For dewatering the effluent (drainage) residue the concentration of the original suspension should be not less than 700 g/liter. The suction method can be used to dewater only residues based on chamotte dust or mixtures of chamotte and clay (not more than 20%); on the drum vacuum filter even with a mixture of chamotte and clay (not more than 20%) we obtain unsatisfactory results. To dewater suspensions containing chamotte and clay dust it is possible to use vacuum-filters with a residue feed using the overflow method, but such vacuum-filters are not being made by Soviet industry. Vacuum filtration as a method of dewatering residues from drainage contaminated with chamotte and clay is not recommended. Using centrifuging: The residues of the effluents can be dewatered on centrifuges; it is best to dewater residues formed from the coagulation of drainage water than residues formed from noncoagulated drainage. Centrifuging is affected by the nature of the formation of the original material. It is necessary to continue the research into laboratory and production centrifuges.

In HeLa cells, complete inhibition of oxidative phosphorylation by oligomycin, myxothiazol or FCCP combined with partial inhibition of glycolysis by DOG resulted in a steady threefold decrease in the intracellular ATP level. The ATP level recovers when the DOG-containing medium was replaced by that with high glucose. In 48 h after a transient (3 h) [ATP] lowering followed by recovery of the ATP level, the majority of the cells commits suicide by means of apoptosis. The cell death does not occur if DOG or an oxidative phosphorylation inhibitor was added separately, treatments resulting in 10–35% lowering of [ATP]. Apoptosis is accompanied by Bax translocation to mitochondria, cytochrome c release into cytosol, caspase activation, reactive oxygen species (ROS) generation, and reorganization and decomposition of chromatin. Apoptosis appears to be sensitive to oncoprotein Bcl-2 and a pancaspase inhibitor zVADfmk. In the latter case, necrosis is shown to develop instead of apoptosis. The cell suicide is resistant to cyclosporine A, a phospholipase inhibitor trifluoroperazine, the JNK and p38 kinase inhibitors, oligomycin, N-acetyl cysteine and mitoQ, differing in these respects from the tumor necrosis factor (TNF)- and H2O2-induced apoptoses. It is suggested that the ATP concentration in the cell is monitored by intracellular “ATP-meter(s)” generating a cell suicide signal when ATP decreases, even temporarily, below some critical level (around 1 mM).

Mitochondria can be a source of reactive oxygen species (ROS) and a target of oxidative damage during oxidative stress. In this connection, the effect of photodynamic treatment (PDT) with Mitotracker Red (MR) as a mitochondria-targeted photosensitizer has been studied in HeLa cells. It is shown that MR produces both singlet oxygen and superoxide anion upon photoactivation and causes photoinactivation of gramicidin channels in a model system (planar lipid bilayer). Mitochondria-targeted antioxidant (MitoQ) inhibits this effect. In living cells, MR-mediated PDT initiates a delayed (“dark”) accumulation of ROS, which is accelerated by inhibitors of the respiratory chain (piericidin, rotenone and myxothiazol) and inhibited by MitoQ and diphenyleneiodonium (an inhibitor of flavin enzymes), indicating that flavin of Complex I is involved in the ROS production. PDT causes necrosis that is prevented by MitoQ. Treatment of the cell with hydrogen peroxide causes accumulation of ROS, and the effects of inhibitors and MitoQ are similar to that described for the PDT model. Apoptosis caused by H2O2 is augmented by the inhibitors of respiration and suppressed by MitoQ. It is concluded that the initial segments of the respiratory chain can be an important source of ROS, which are targeted to mitochondria, determining the fate of the cell subjected to oxidative stress.

It was shown in [i] that, in the presence of a severe stress raiser such as a crack about 0.1 mm deep, high-strength steels in a stressed state may fracture under the action of corrosion-active environments (water, sodium chloride solution) and in media not corrosive to the steel in a nonstressed state (potassium bichromate solution, a solution of potassium bichromate and sodium carbonate). In this connection, it was suggested in [i] that the adsorption of water at the base of the crack may be the reason for the fracture of the steel in the above cases. Studies of the fracture of stressed specimens of high-strength steel SP-28 having a central, through fatigue crack in neutral sodium chloride solutions showed that fracture occurs in two stages: slow crack growth, associated with local anodic dissolution of metal at the tip of the growing crack, giving way to hydrogen embrittlement.

The properties of powders of alumina produced by topochemical reaction, and the density and microstructure of corundum ceramic specimens produced from the powder depend on the crystallochemical characteristics of the original salt. A high-density visually transparent corundum ceramic can be produced successfully from the salt AlCl3·6H2O. Corundum ceramic produced without added modifying agent from the salt AlCl3·6H2O is of high relative density, viz., 97.9%.

A built-up degree of damage μ=Δf/fo ≤8% has virtually no effect on the static strength of an AD33-B CM operating in air. The arbitrary fatigue limit corresponding to this volume of damage on a basis of 2–105 cycles may be taken to be equal to (0.5–0.55) σt. Accelerated buildup of damage on a basis of 2–105 cycles is observed at σa > (0.5–0.55) σt.

With low volumes of accumulated damages (Μ⩽8%) to a test base of 2 · 105 cycle in not more than 150 h the influence of corrosive media on the residual strength of AD33-B composite is not significant. At levels of cyclic stresses of σa>0.6σb, the use of AD33-B composite in 3% NaCl solution and water is undesirable without anticorrosion measures.

The residue formed from effluent contaminated with chamotte dust, with coagulation and without coagulation, is thoroughly dewatered on vacuum equipment with concentrations of more than 700 kg/m3 of suspended particles in the residue. Residues obtained from effluent contaminated with mixtures of chamotte and clay dust in the ratio 4∶1, 1∶1, and 1∶4 are dewatered less effectively than chamotte residues. The residue from a mixture of chamotte and clay 4∶1 is dewatered with a minimum concentration of 809 kg/m3; the residue from the mixture of chamotte and clay 1∶1 can be satisfactorily dewatered only with a high vacuum (640 mm Hg) and with a filter cycle time longer than that used in existing equipment. With a filter cycle of 30 min the thickness of the skin of uncoagulated residue was 13 mm. The coagulated residue from a mixture of clay and chamotte 1∶1 even after 14 days holding had too low a concentration, and in practice cannot be dewatered on a vacuum filter. The residue from mixtures of 1∶4 chamotte and clay is dewatered very ineffectively. The thickness of the cake with a filter cycle time of 20 min for uncoagulated residue was only 4 mm.

Red blood cells bearing anti-mouse IgG antibody on their surface (immunoerythrocytes) may provide for local protection of endothelial cells from the action of hydrogen peroxide. Subconfluent cultures of human umbilical vein endothelial cells responded sharply to increasing concentrations of hydrogen peroxide. Permeabilization of cellular membrane occurred at doses of hydrogen peroxide of from 1 to 3 mM, and was assured by incorporation of trypan blue stain immediately after treatment. Latent damage of cells produced by much lower doses of hydrogen peroxide (0.2-0.4 mM) could be observed after 24-hour incubation of treated cells in the normal culture medium with no hydrogen peroxide. The apparently dead cells differed from intact cells in morphology, were poorly attached to the substrate, and were readily incorporated by trypan blue, thus permitting easy visualization. Immunoerythrocytes bound to the antigen-coated surface enzymatically decreased the concentration of hydrogen peroxide in their microenvironment at least fivefold with respect to the total hydrogen peroxide concentration. Erythrocytes deposited on a part of the endothelial monolayer locally protected it from the damage at hydrogen peroxide concentrations ranging from 0.4 to 1.2 mM. Localization of protected zones corresponded precisely to the geometry of the erythrocyte coating. Immunoerythrocytes targeted to the endothelial cells by means of mouse anti-endothelial antiserum did not impair their viability and protected the endothelium from being killed at 0.3-1.2 mM hydrogen peroxide. This approach might be useful for a cell selection in mixed cell populations. The problem of local protection of cells involved in the inflammation focus are discussed.

Amount of inter--and extracellular unfrozen water in the intact human erythrocytes as well as tau a, "a life time" of water molecules in these cells, have been determined. The progressive compression of the erythrocytes during freezing them as deep as -5 degrees C has been found to submit to the ideal osmometer law. The membrane impermeability to Mn2+ ions has been disturbed when the temperature falls to -7 degrees C and below, the erythrocytes reaching "the minimal volume".

It is shown that diffusive water permeability of E. coli cell membranes at 4-24 degrees C is in the range from 16.6 to 35.0 microM.s-1, that is close to erythrocyte membrane water permeability, but higher than that of lipid bilayers. Cryoprotectants (DMSO and thiourea) at the concentration of 1.0 M considerably decrease water bacterial membrane permeability. 1.5- and 2-fold, respectively. The obtained results are discussed in relation to two possible water transport ways through pores of the protein nature or lipid bilayer damages.

In tests set up on albino rats, guinea pigs and rabbits the chronic toxicity of hygronium--a new original ganglion blocking agent of a short-term action was studied. With its daily intraperitoneal administration for 14 days in doses of 10 and 40 mg/kg (1/10 and 1/3 DL50) the drug produces in some of the animals, chiefly in rabbits and guinea pigs receiving 40 mg/kg, readily reversible histological changes in some of their internal organs. Hygronium does not cause any local irritating effect

Results of an immuno-morphological analysis of the I, II, IV and V collagen types in 7 synovial sarcomas of various location are presented. A fibrillar matrix of synovial sarcomas is represented by a collagen of type I and collagen of type V which is co-distributed with the former. Collagen of type III is found in a smaller quantity and in areas of fibrosarcoma-like structure being included in the largest fibrillar structures. Collagen of type IV is presented in all structural areas of tumours. The greatest amount of the IV type collagen is observed in areas of the epithelioid and hemangiopericytoma-like structure, less in areas of fibrosarcoma-like structure. These results may be used in differential diagnostics. In the walls of fissure-like spaces, only the IV type collagen was found as distinct from vascular tumours. On the basis of the data obtained and analysis of the literature a mesodermal origin of synovial sarcoma is suggested.

Design and some features of polarized proton beam-line are described. For slow extracted proton beam of intensity 1013 ppp the total flux of secondary protons produced by λ decays is to be of the order of 5·106, polarization is about 40% at 53 GeV/c. This project is under discussion at IHEP.