In order to evaluate the photosynthetic activity of a C3 leaf from the electron transport rate (ETR) of photosystem 2 (PS2), a new method was devised and examined using leaves of sweet potato. In this method, both surfaces of a leaf were sealed with transparent films to stop the gas exchange between the leaf and the atmosphere; hence the functions of both photosynthetic assimilation (CO2 uptake) and photorespiration (CO2 release) are restricted to the inside of the leaf. After both functional rates became equally balanced, ETR of the sealed leaf (ETRseal) was determined from the chlorophyll fluorescence. The measurements were conducted at different irradiances and leaf temperatures and by using leaves of different age. Under each measurement condition, ETRseal showed a close positive relationship with the photosynthetic potential, or the gross photosynthetic rate measured in the air of 2 % O2 (PG2%) before sealing. ETRseal may become an indicator to estimate or evaluate the photosynthetic activity of C3 leaves. and Haimeirong, F. Kubota, Y. Yoshimura.
Kompaktní toroidální magnetické nádoby pro uchovávání termojaderného plazmatu mají poměr velkého a malého poloměru (aspect ratio) blízký jedničce. Ačkoli jsou považovány za termojaderná zařízení vyvíjená a studovaná mimo hlavní proud výzkumu termojaderné fúze, jejich zkoumání rozhodně má svoji cenu., This article looks for common features of magnetic confinement methods for high temperature plasmas such as spherical-tokamak, plasma focus, spheromak and Field Reversed Configuration (FRC). Most members of this series of methods make significant use of the self-organized magnetic field in plasmas. The self-organized magnetic field in plasmas is commonly found in the universe. In the laboratory, the self-organized magnetic field in plasmas is used by some private companies engaged in thermonuclear fusion., Milan Řípa., and Obsahuje bibliografii