Cytogenetic and blastomogenic effects of 45Ca and 131I administered to rats

The cytogenetic research of the mutagenic action of 45Ca, 131I and 45Ca and 131I simultaneously after a single introduction into the stomach was carried out on the peripheral blood lymphocytes of rats. Tumours of different localization were diagnosed in these animals. Positive correlation between mutagenic and carcinogenic effects is shown (r = 0.93, the relation degree of these signs is found to be 87% at P less than 0.001). An assumption is advanced that the quantity and the quality of the stable cytogenic disturbances in somatic cells (blood lymphocytes) may have diagnostic and prognostic significance under the effect of radionuclides.     

On the experimental data processing of magnetoresistance oscillations in two-dimensional electron gas

A new method for processing data on the Shubnikov-de Haas effect in quasi-two-dimensional systems is suggested.     

Interference of emission from disk-shaped lasers based on quantum-confined AlGaAsSb/InGaAsSb nanoheterostructures

Directivity patterns of disk-shaped whispering gallery mode (WGM) semiconductor lasers based on quantum-confined AlGaAsSb/InGaAsSb nanoheterostructures have been studied. The cavities of disk lasers were manufactured by wet chemical etching and had the shape of a truncated cone with a height of 15 μm. The top (about 5-μm-high) part of the cavity had a cylindrical shape. A flat ring with a width equal to the thickness of the active region was protruding ～1 μm out of the side face of the cavity. The directivity diagram of the disc WGM laser exhibits a ring-shaped interference pattern with several maxima separated by an angle of ～6°. The interference pattern observed in both spontaneous and laser generation regimes can be explained by the interference of rays emitted directly from the ring and those reflected from the etched surface of the crystal.     

Frequency-tuned semiconductor whispering-gallery-mode laser (λ = 2.35 µm) operating at room temperature

Technical Physics Letters - Frequency tuning in a whispering gallery mode (WGM) semiconductor laser (λ = 2.35 µm) with a sector (half-disk) cavity has been studied. Pumping by current...     

Generation of π modes in semiconductor vertical-cavity surface-emitting lasers

We have theoretically and experimentally studied optical emission from the side faces of mesa structures for vertical-cavity surface-emitting lasers (VCSELs). The results of spatially resolved spectral measurements show that a new type of lasing modes is found in VCSELs with circular mesa structures, which corresponds to the π mode propagation along the mesa diameter with reflection from the sloped walls and the bottom Bragg mirror.     

The influence on tumor growth and the function of the thiol-dependent systems of the liver of excess cooking fat and vitamin E in the diet. The effects of carminomycin

A study was made of the influence of excessive culinary fat in the diet containing 30% of trans-isomers and tocopherol on tumor growth, parameters of antitumor and toxic action of carminomycin, and the state of thiol-dependent defensive systems of the liver. The data obtained have evidenced a negative influence of the experimental ration on the survival of the tumor-carriers and on the condition of the normal animals. Activation of the glutathion S-transferase system attended by the exhaustion of the thiol pool in the liver was recorded. Carminomycin toxic action was not modified by the experimental diet.