Multilayered graphene in K(a)-band: nanoscale coating for aerospace applications.

We report on the experimental study of electromagnetic (EM) properties of multilayered graphene in K(a)-band synthesized by catalytic chemical vapor deposition (CVD) process in between nanometrically thin Cu catalyst film and dielectric (SiO2) substrate. The quality of the produced multilayered graphene samples was monitored by Raman spectroscopy. The thickness of graphene films was controlled by atomic force microscopy (AFM) and was found to be a few nanometers (up to 5 nm). We discovered, that the fabricated graphene, being only some thousandth of skin depth, provided remarkably high EM shielding efficiency caused by absorption losses at the level of 35-43% of incident power. Being highly conductive at room temperature, multilayer graphene emerges as a promising material for manufacturing ultrathin microwave coatings to be used in aerospace applications.

In vitro antifungal activity of phenylheptatriyne from Bidens cernua L. against yeasts.

In vitro antifungal activity of phenylheptatriyne from Bidens cernua L. (Asteraceae) was studied using broth macrodilution method against 125 strains of yeasts including 104 clinical and other isolates of Candida spp. (C. albicans, C. krusei, C. tropicalis, C. guilliermondii, C. parapsilosis, C. glabrata, C. inconspicua), 16 strains of basidiomycetous yeasts (Cryptococcus neoformans, C. albidus, Trichosporon cutaneum, Rhodotorula glutinis) and five standard reference strains of Candida species. Phenylheptatriyne has shown significant activity against investigated strains, and the Minimal Inhibitory Concentrations for Candida spp. were determined as 12.5-50 microg/ml and for basidiomycetous yeasts as 12.5-100 microg/ml.

[Antioxidant effect of the antineoplastic antibiotic obtained from a plant of the family Asteraceae]. / Antioksidantnoe deistvie protivoopukholevogo antibiotika, poluchennogo iz rasteniia semeistva slozhnotsvetnykh.

Antitumour antibiotic from a plant of the family Asteracea has been studied for the biochemical mechanism of its action. Redox processes were tested by the method of spontaneous chemiluminescence determining the intensity of freely radical oxidation of membrane cell phospholipids. It was established that the antibiotic under study stabilized the indices of spontaneous chemiluminescence up to the normal level.

[Blood flow in the microvessels of the cerebral cortex]. / Dinamika krovotoka v mikrososudakh poverkhnosti kory golovnogo mozga.

To measure dynamic characteristics of linear velocity of the blood flow in microvessels on the surface of rat's brain, the method of accelerated cinemicrography was used. The blood flow velocity varied from 500 to 5000 mu/sec in microvessels with diameter of 7-15 mu. The blood flow fluctuated with the rate of 1-3 oscillations per second and the amplitude 20-50% of the average value. Auto- and crosscorrelation analysis of the processes revealed in 35% of the cases a positive correlation between shifts of velocities and the frequency of their occurrence. No correlation existed between rapid changes of the blood flow in adjacent or distant microvessels. The sharp changes of blood flow seem to be due to periodical passage of leucocytes and accumulated erythrocytes which increase resistance against the blood flow in microvessels.