Correlation of the production of gonadotropic and sex hormones in boys and girls during sex maturation

There is an early period of puberty in boys at the age of 10 to 13, accompanied by an increase in the level of follicle stimulating hormone and a low secretion of luteinizing hormone and testosterone, with no secondary sexual signs. The beginning of an increase in the luteinizing hormone and testosterone concentration in boys coincides with the development of secondary sexual signs. The stabilization of the level of luteinizing hormone takes place in boys already at the 2nd degree of the sexual development. The secretion of luteinizing hormone at this point corresponds already to the normal level in adult men. The level of testosterone in the blood continues to increase and does not reach its definitive level until after the age of 17, or at the 5th degree of sexual development. Like in boys, the increase of the follicle stimulating hormone in girls precedes the increase of the luteinizing hormone secretion. The beginning of the increase in the follicle stimulating hormone coincides with an increase in the level of estrogens and testosterone in the blood, and with the appearance of secondary signs of sexual maturation. The increase of the luteinizing hormone secretion takes place later in girls than in boys and is accompanied by a new and significant increase in the level of estrogens in the blood. At the 2nd degree of sexual development, the level of testosterone in the blood of girls is substantially higher than at the other stages.     

Comparative analysis of seismic methods for oil recovery enhancing

A scheme is developed for the comparative analysis of seismic technologies of oil recovery enhancing by the distinguished features. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 63–75, May–June, 2006.     

Two-Stream Free Electron Lasers: Physical Analysis of the Systems with Monochromatic Pumping

Nonlinear selfconsistent theory of the Two-stream Superheterodyne Free Electron Lasers (TSFELs) is represented. The one-sectional and klystron type models of TSFEL-amplifiers are analyzed. It is shown that such systems can provide extremely high levels of amplification, and, at the same time, high levels of the input-output decoupling.     

Quartz Resonators for Monitoring Thin-Film Mass and Thickness

A detailed analysis is presented for a quartz resonator-film system that substantially improves the accuracy in determining the mass and thickness. A proposed method of measuring the mass and other physical properties of the films is tested by experiment, which does not require preliminary calibration.__________Translated from Izmeritelnaya Tekhnika, No. 2, pp. 29–32, February, 2005.