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The mass separation of chemical element mixtures is a relevant task for numerous applications in the nuclear power industry. One of the promising approaches to solve this problem is plasma mass separation. In a recent study, the efficiency of plasma mass separation in a configuration with a potential well and a homogeneous magnetic field was experimentally demonstrated. This article examines the possibility of increasing the distance between the deposition regions of charged particles with different masses by varying the profile of the electric field potential. Such correlation can be considered as the control in a system of active particles. A cylindrical coordinate system is used. The electric field is axially symmetrical, and the magnetic field is directed along the axis of the symmetry. The corresponding mathematical problem was solved in a general way. The criteria for increasing the distance between the deposition areas of the "light" and "heavy" components of the mixture have been formulated. A high sensitivity of particle trajectories to the electric field potential in the region of the pericentres of the trajectories of charged particles was detected. Recommendations for the practical implementation of the optimal spatial separation of ion fluxes are proposed.

We studied the effect of low and high-dose rate photon radiation on activation of cell death by apoptosis and necrosis in malignant cell lines of lymphocytic origin Raji and Jurkat (human B and T-cell lymphomas) and normal human lymphocytes from healthy volunteers. It was shown that photon radiation with ultra-high dose rate induced significantly higher levels of "early" apoptosis and lower levels of necrosis compared to γ-radiation with dose rate used for radiation therapy.

We have shown that, in determining the biomolecule-crystal symmetry, the occupation of low-site-symmetry Wyckoff positions is crucial, which contrasts with the overwhelming majority of nonmolecular, inorganic crystals where atoms mainly reside in high-symmetry Wyckoff positions. We consider the general relation between the symmetry of an isolated molecule and the possible symmetries of biomolecular crystals it can generate. We reveal that the improper symmetry operations (inversion and mirror symmetries) are prohibited in the chirally pure biomolecular crystals. Next, we show that the low (C1) symmetry of large biological molecules substantially decreases the space in a crystal where the molecules can reside. The space "forbidden" for molecule centers is found to be in the R vicinity of the higher-symmetry Wyckoff positions on symmetry lines, where R is the molecule characteristic size. The remaining free space and hence the probability for the structure to exist are shown to be drastically increased when replacing any rotation axis by a screw one. Based on the proposed model, we have explained the peculiar distribution of biomolecular crystals over the space groups, which can be obtained from biomolecule-crystal databases.

The permeabilization of tumor cells in vitro under the action of pulsed electric fields with a duration of 6 mks in the range of amplitudes 1-7 kV/cm was studied. In the mode of excitation in the ambience of localized plasma discharge in a chamber of special design, an enhanced damage to cells in suspension was observed. It is assumed that the enhancement is due to the synchronous action of the electric field and acoustic shock wave pulses. In the mode without the plasma breakdown of ambience, when the pulse duration of electric field of intensity of 1-2 kV/cm was increased to 60 mks, the efficiency of permeabilization increases nearly by one order. The experimental results are compared with the known theoretical models of cell membrane electroporation.

Morphological study of serial section biopsies from 22 children was made to develop new diagnostic criteria of a latent form of terminal ileitis. The following changes were observed: fibroblastic reaction around the lymphoid follicles, degenerative changes of enterocytes close to the lymphoid follicles; disruption of basal membrane over the lymphoid follicles; penetration of lymphoid cells into the intestinal lumen and their adhesion to the apical membrane of enterocytes; neuroma-like structures as an issue of productive vasculitis. The frequency of the symptoms above 62% does not depend on the sex, age and treatment method.

We present the results of comparative experimental studies of the damaging effect of intense electrical field with a microsecond duration range, shock acoustic wave, and their combination on the ovary carcinoma cells. We found that upon a combined effect of pulse electrical and acoustic shock-wave fields of a moderate amplitude, practically all cells died. A qualitative physical model is proposed, which accounts for enhanced damage upon combined effect, on the one hand, by a decreased threshold of electric intensity of the cytoplasmic membrane breakdown at a temporal phase of pressure compression of the shock-wave pulse and, on the other hand, by a growth of cavitational embryos at a temporal phase of the action of stretching tensions of the shock-wave pulse, whose role is played by hydrophobic type pores appeared as a result of the membrane electrical breakdown. Possibilities of practical application of the proposed combined effect are discussed: in oncology for suppression of tumor growth and in biotechnology for cell disintegration and ecologically pure sterilization of liquid media.

A study was made of effects of transcardiac galvanization (TCG) on activities of a panel of oxidation-reduction enzymes as well as on the cardiac muscle content of high energy substrates, and size of the lesion area, in experimental myocardial infarction (EMI) in 50 albino male rats. After two TCG procedures, and at 24-h EMI, augmentation was found of activities of succinic dehydrogenase, lactate dehydrogenase, NADH-dehydrogenase, beta-hydroxybutyrate dehydrogenase, both in the area of profound ischemia and peri-infarction myocardium, this being accompanied with an increase in myocardial content of adenosine triphosphate, creatine phosphate, and glycogen, and reduction of the developing mass of necrosis. Stimulation of enzyme activity in the course on the enzyme complex and membrane-stabilizing action of this preformed physical factor.

The model of experimental myocardial infarction in rats was used to study the effect of procedures of transcardiac galvanization (the current power 4 mA, duration 60 min) on the condition of the peri-infarction zone microcirculatory bed. The morphometric studies of the microcirculatory bed were performed using PAS reaction with amylase using a net with equidistant points. Two runs of transcardiac galvanization by the end of the first 24 hours of myocardial infarction was shown to improve the condition of the capillary network, to increase the relative and absolute area of the capillaries, the number of opened reserve capillaries, to reduce the distance of oxygen and metabolites diffusion from capillaries to cardiomyocytes in the peri-infarction zone thereby creating favourable conditions for the remaining viable myocardium and for stabilization of the affected zone.

Activity of ATPase in functional element of myocardium (its qualitative and quantitative aspects) has been researched in normal tissue and in one with various levels of hypothermic ischemia (28-30 degrees C and 10-12 degrees C) by methods of electron microscopic histochemistry on dogs. It has been found that hypothermia of myocardium (10-12 degrees C) optimally prevents ischemic disorders of energetic processes. Reproduction activity of ATPase during reperfusion of myocardium after that hypothermia maintains contractile function of heart in proper high level.

The state of main structures of the functional element of the canine myocardium has been estimated at ether-oxygen narcosis. Heterogeneity of blood supply, histological and histochemical organization of the myocardium depends on its topological differentiation.

Erythrocyte morphology, their aggregation ability and microcirculatory pattern in the mesentery of the small intestine have been studied stepwise on 12 dogs under artificial blood circulation. It has been shown that erythrocyte lesions followed by pathological aggregation play an important role in the pathogenesis of microcirculatory failure. Prolonged artificial circulation provokes structural reorganization in erythrocytes, thus affecting both blood rheology and gas exchange.

In cancer of the pancreatoduodenal zone complicated by obturative jaundice it is expedient to perform pancreatogastroduodenal resection in two steps: the first step is laparoscopic hepatocholecystostomy, the second step should be fulfilled 10-12 days after normalization of bilirubinemia. The data obtained were taken into consideration in pancreatogastroduodenal resection performed in 20 patients.