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1.
Rev Sci Instrum ; 90(11): 113501, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31779455

ABSTRACT

Due to an increased interest in runaway electron (RE) phenomena in tokamak research, the need for diagnostics of runaway electron population in plasma has emerged. A novel diagnostic of the nonthermal electron cyclotron emission from runaway electrons can be utilized for this purpose. It was designed and installed at the COMPASS tokamak based on the available heterodyne radiometer. The vertical ECE (V-ECE) system uses a 16-channel heterodyne radiometer with a vertically placed E2-band horn antenna with a 76.5-90 GHz frequency range front-end. Simulations with the ray-tracing SPECE code have shown a measurement feasibility of the runaway electrons with energies up to 1 MeV. Due to a low optical depth of the plasma in COMPASS during RE discharges, reflected waves from the tokamak wall can be detected as well. First results show strong connection with other RE diagnostics at COMPASS. The V-ECE can obtain important information about RE population evolution and primary generation mechanism.

3.
Ceska Slov Farm ; 46(6): 247-55, 1997 Dec.
Article in Czech | MEDLINE | ID: mdl-9600146

ABSTRACT

Leuzea carthamoides (WILLD.) DC., Asteraceae, has become an important taxon usable in human practice and animal production in recent years. Originally an endemic plant of southern Siberia, now it is widely grown not only in the Union of Independent States, once the original region of introduction, but also in central and eastern Europe. The principal constituents of the whole plant are ecdysteroids (5 beta-cholest-6-on-7-ene derivatives) and flavonoids. In addition, the aerial part contains sesquiterpenic lactones of the guajanolide type, and the roots contain polyines (on the thiophene base). The present paper comprehensively discusses the occurrence, content and biological activity of these substances, the preparations manufactured from the plant, their use in therapeutic practice, food manufacture and animal production in the world and the Czech Republic. The plant has certainly become a taxon with prospects in the Czech Republic, particularly as the source of 20-hydroxyecdysone, which is getting into the limelight in the world.


Subject(s)
Plant Extracts/chemistry , Plant Extracts/therapeutic use , Plants, Medicinal , Animals , Cardiovascular Diseases/prevention & control , Humans , Plant Extracts/pharmacology
4.
Vet Med (Praha) ; 31(6): 347-57, 1986 Jun.
Article in Czech | MEDLINE | ID: mdl-3088806

ABSTRACT

The concentration of testosterone, 17-beta oestradiol and aflatoxin B1 were studied in the semen plasma of 21 boars of four breeds for the period of twelve months. The following spermiological parameters were investigated: semen volume, sperm concentration, percentage of abnormal spermatozoa, and survival of spermatozoa. The fertilizing capacity of ejaculates was evaluated according to the conception rate of sows and gilts after the first insemination, according to the average number of piglets per litter and average number of live-born piglets per litter. The highest aflatoxin B1 residues in sperm were recorded in March to May and were related with aflatoxin concentration in feed ration. The group of boars with fertility disorders had more aflatoxin in their sperm (up to 100 pmol . l-1), lower sperm concentration, lower survival of spermatozoa, and a larger proportion of abnormal spermatozoa. The year season had a significant influence on the concentration of the hormones. The highest average value of testosterone (10.2 +/- 1.28 nmol) was obtained in autumn and lower values were recorded in winter. The changes in 17-beta estradiol concentration were similar to the changes in testosterone content, with the maximum value in November (0.249 nmol X 1(-1]. The boars with reproduction disorders had a significantly lower concentration of 17-beta oestradiol. Significant correlations were found between the concentration of the hormones, semen volume, and sperm concentration. 17-beta oestradiol also had a significant positive correlation to abnormal spermatozoa and to the activity of aspartate aminotransferase.


Subject(s)
Aflatoxins/analysis , Estradiol/analysis , Semen/analysis , Spermatogenesis , Swine/metabolism , Testosterone/analysis , Aflatoxin B1 , Animal Feed/analysis , Animals , Aspartate Aminotransferases/analysis , Female , Male , Pregnancy , Seasons , Sperm Count
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