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Start Over Coverage 429-442

2. Photosynthetic parameters of maize (Zea mays L.) inbred lines and F1 hybrids: Their different response to, and recovery from rapid or gradual onset of low-temperature stress

Creator:
Holá, D., Langrová, K., Kočová, M., and Rothová, O.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
carotenoids, chlorophylls, genotypes, Hill reaction, intra-specific variability, and photosystem 1 and photosystem 2
Language:
Multiple languages
Description:
The activity of photosystems (PS) 1 and 2, together with the content and ratio of photosynthetic pigments, were measured in three inbred lines and two F1 hybrids of maize (Zea mays L.), grown in either optimum or low temperature (LT) conditions. The ability of chilling-stressed plants to deal with the negative effects of long-term exposure to LT and to recover the efficiency of photosynthetic apparatus after their return to optimum temperatures was examined during spring and autumn seasons. The aim was to analyse the possible differences between the rapid and gradual onset of LT on the response of young maize plants to chilling stress. The distinctive superiority of hybrids over their parental lines, found during the exposure of maize plants to LT, was not always retained after the return of chilling-stressed plants to optimum growth conditions. The response of individual genotypes to chilling stress, as well as their ability to recover the photosynthetic efficiency from the cold-induced damage, strongly depended also on the duration and the rapidity of the onset of LT. and D. Holá ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Some initial boundary problems in electrodynamics for canonical domains in quaternions

Creator:
Meister, E. and Meister, L.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
electromagnetic fields by complex quaternions, initial boundary transmission problems for semi-infinite domains, reduction to Wiener-Hopf pseudo-differential systems, and anisotropic Leontovitch boundary conditions
Language:
English
Description:
The initial boundary-transmission problems for electromagnetic fields in homogeneous and anisotropic media for canonical semi-infinite domains, like halfspaces, wedges and the exterior of half- and quarter-plane obstacles are formulated with the use of complex quaternions. The time-harmonic case was studied by A. Passow in his Darmstadt thesis 1998 in which he treated also the case of an homogeneous and isotropic layer in free space and above an ideally conducting plane. For thin layers and free space on the top a series of generalized vectorial Leontovich boundary value conditions were deduced and systems of Wiener-Hopf pseudo-differential equations for the tangential components of the electric and magnetic field vectors and their jumps across the screens were formulated as equivalent unknowns in certain anisotropic boundary Sobolev spaces. Now these results may be formulated with alternating differential forms in Lorentz spaces or with complex quaternions.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public