Change in the concentration of total lipids, phospholipids and neutral lipids in rat liver mitochondria and microsomes during chemical carcinogenesis

Sharp increase in the content of total lipids and, especially, neutral lipids, and considerable decrease in the content of phospholipids were observed in liver microsomes and mitochondrias from liver of tumour-bearing rats in the process of the growth of sarcoma, induced by a single injection of 3,4-benzpyrene. The injection of anthracene, a non-cancerogenous hydrocarbon, practically did not affect the lipid composition of rat liver subcellular particles. Thus, the disturbances in normal functioning of subcellular particles under cancerogenesis are due to considerable change in the chemical composition of biomembranes. The data obtained confirm our hypothesis on lipid mobilization under tumour growth.     

Analysis of the structure of cardiac rhythm during treatment of auricular fibrillation with digitalis

The structure of cardiac rhythm was studied with the help of specialized computers during digitalization in 60 patients with atrial fibrillation of different etiology. The reduction of the heart contractions rate under digitalization is accompanied by certain changes in the structure of cardiac rhythm: the arrhythmic pattern of the ventricular contractions increases with a predominant growth of the number of long R--R intervals, the transitions from short intervals to longer ones become sharper, and portions of a relatively stable ventricular rhythm appear. Three main types of dynamics of the rhythm structure were distinguished on the basis of the changes in the interval R--R histogram. The described changes in the structure of cardiac rhythm are not specific, but when Digitalis drugs are used alone they can be used as additional criteria for digitalization.     

Mechanism of oxidative phosphorylation. IV. Role of the closed state of mitochondrial membranes

The clousness of membrane of rat brain mitochondria isolated in Krebs-Ringer's solution was broken by suspending the mitochondria in distilled water. Function characteristics of lyzed organells did not decrease but were somewhat higher than those of the organells suspended in Krebs-Ringer's solution. The results were discussed in relation to the question of the role of clousness of the mitochondrial membrane in the mechanism of oxidative phosphorylation.     

Nanofabrication with Pulsed Lasers

An overview of pulsed laser-assisted methods for nanofabrication, which are currently developed in our Institute (LP3), is presented. The methods compass a variety of possibilities for material nanostructuring offered by laser–matter interactions and imply either the nanostructuring of the laser-illuminated surface itself, as in cases of direct laser ablation or laser plasma-assisted treatment of semiconductors to form light-absorbing and light-emitting nano-architectures, as well as periodic nanoarrays, or laser-assisted production of nanoclusters and their controlled growth in gaseous or liquid medium to form nanostructured films or colloidal nanoparticles. Nanomaterials synthesized by laser-assisted methods have a variety of unique properties, not reproducible by any other route, and are of importance for photovoltaics, optoelectronics, biological sensing, imaging and therapeutics.     

Dynamic behavior of HIPed Ti–6Al–4V

The overall dynamic properties of hot isostatically pressed (HIPed) Ti–6Al–4V were throughout investigated. MIL-T-9047G was chosen as a standard material for property comparison due to its best combination of strength and ductility. The elastic constants of HIPed Ti–6Al–4V were measured by resonant ultrasound spectroscopy (RUS) method. Three types of Hopkinson bar tests (constitutive relations tests, strain-controlled specimen tests and hat-shaped specimen tests) were conducted on HIPed material as well as on the standard material to evaluate the high-strain-rate properties of HIPed Ti–6Al–4V. Thick wall cylinder explosion test was conducted to compare the post-critical behavior of baseline material (MIL-T-9047G) and Ti–6Al–4V HIPed material. The texture effect in high-strain-rate properties was checked as the main difference between HIPed (texture free) and standard material (grains elongated along the rod axial direction). The results show that the nonmilled HIPed Ti–6Al–4V has similar yield strength and strain-hardening curve in comparison with the standard material in forging direction but has a lower ductility, which is similar to the ductility of standard material normal to forging direction. The same conclusion also generated from the strain controlled specimen tests. The results that obtained in hat-shaped specimen tests show that HIPed material starts shear localization relatively earlier than standard material. This result is somewhat contradicted with the ballistic testing results that show better ballistic performance for HIPed materials in all three types of penetration tests (flat-ended, conical and long-rod) [see Refs. Nesterenko VF, Indrakanti SS, Goldsmith W, Gu Y. In: Staudhammer KP, Murr LE, Meyers MA, editors. Fundamental issues and applications of shock-wave and high-strain-rate phenomena. Amsterdam: Elsevier Science; 2001. p. 593–600; Nesterenko VF, Indrakanti SS, Brar S, Gu Y. Shock compression of condensed matter. AIP Conf Proc 2000; 505(1): 419–22; Nesterenko VF, Indrakanti SS, Brar S, Gu Y. Key Eng. Mater. 2000; 177-180: 243–8; Nesterenko VF, Goldsmith W, Indrakanti SS, Gu Y. Int J Impact Eng 2003; 28(2): 137–60; Gu Y, Indrakanti SS, Nesterenko VF. Shock compression of condensed matter. AIP Conf Proc 2002; 620(1): 1294–7]. The explanation for this contradiction might be the influences coming from the texture, and other microstructure features such as phase content, grain size distribution and fast shear localization propagation path at the grain boundary and the phase interface.     

Corrosion resistance of nickel steel and nickel alloys in aggressive media

The corrosion resistance of austenitic steel and nickel alloys is studied in the most aggressive media within the chemical shops of coke plants: in the stock solutions of the sulfate department and in sulfuric-acid solutions used for the purification of crude benzene. In the study, the most dangerous ions, activating corrosion in 10X17H13M2T steel, are CNS^? ions, which are capable of destroying the passive layers on chromium-nickel-molybdenum steel in the stock solutions of the sulfate department. Research shows that sulfuric-acid solutions used for the purification of crude benzene are very aggressive in relation to high-alloy steel, titanium, zirconium, and copper. Possible structural materials for use in contact with such solutions include the nickel alloys ХН63МБ, ХН65МВНУ, and Hastelloy C-276.