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Start Over Coverage 425-434

1. Influence of iron nutrition on chlorophyll contents, photosynthesis and essential monoterpene oil(s) in Java citronella {Cymbopogon winterianus Jowitt)

Creator:
Misra, A. and Srivastava, N.K.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Java citronella suffers from chlorosis of the younger leaves, particularly in tropical climatic conditions. An Fe-efFicient genotype of this species was grown in Solutions containing 0 to 44.80 g(Fe) m'^ in controlled glasshouse conditions. In comparison with normál Fe nutrition (5.60 g m"^), low (0 - 1.40 g m'^) or high (22.40 - 44,80 g m*^) iron nutrition influenced fresh and dry matter yield, plant height, total essential oil and citronellol contents, chlorophyll (Chl) content, net photosynthetic and transpiration rates, and Fe uptake. Largest differences were found in saccharide and Chl a and h contents and Chl a/h ratio, and stomatal resistance. Significarít positive correlations were observed between fresh matter, citronellol content, dry and fresh matter yields and total essential oil content.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Reduction of seismic effects on bridges by using seismic isolators

Creator:
Sokol, Milan, Lukáč, Rastislav, and Ároch, Rudolf
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
concrete bridge, seismic analysis, seismic isolator, and lock-up devices
Language:
English
Description:
Seismic effects on a planned highway bridge in active seismic zone near Žilina (Slovakia) were analysed. Seismic analysis has proved that due to strong earthquake an inelastic structural response is likely. Due to great seismic design forces, increase of foundation dimensions was necessary. An alternative solution has been proposed using seismic isolators and dampers that reduce the seismic design forces in piers. As a result, the change of the dimensions was not necessary. These two alternatives and estimated costs were compared. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. The mechanism of the ozone-induced changes in thermoluminescence glow curves of barley leaves

Creator:
Skotnica, J., Gilbert, M., Weingart, I., and Wilhelm, C.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
antimycin A, DCMU, 2,5-dimethyl-1,4-benzoquinone, diphenyleneiodonium chloride, Hordeum, nigericin, oxygen, photosystem 2, and propyl gallate
Language:
Multiple languages
Description:
The changes in thermoluminescence (TL) signals induced by short-term ozone exposure of leaves are characterized by a down-shift of the peak-temperature of the TLB-band and an increase of a TL band at 55°C. We investigated the relationship of these changes to photosystem 2 (PS2) photochemistry. The changes were not only detectable in the presence of ozone, but also after irradiation of dark-adapted leaves and after aging of irradiated detached leaf segments. The opposite effect on TL, an up-shift of the peak-temperature of the B-band and the decrease of the intensity of the band at 55°C were found after infiltration of leaves with nigericin, antimycin A, and diphenyleneiodonium chloride (DPI). Propyl gallate down-shifted the peak-temperature of the B-band. 2,5-dimethyl-1,4-benzoquinone up-shifted the peak-temperature of the B-band and decreased the intensity of the 55°C band. The intensity of the 55°C band did not change significantly in the presence of oxygen in comparison to that in nitrogen atmosphere. It decreased with time of dark adaptation (50% intensity was observed after 3 h of dark adaptation at room temperature), however, it was reactivated to its initial value (at 5 min of dark adaptation) after 1 single-turnover flash. The 55°C band was not significantly changed in the presence of DCMU. Thus the ozone-induced band at 55°C is assigned to charge recombination in PS2. Changes in the electron transport chain at the acceptor side of PS2, probably related to the cyclic electron transport around photosystem 1 and/or chlororespiration, could play an important role in the increase of the 55°C band and the down-shift of the B-band. The changes at the acceptor side indicated by TL can be an ex pression of a physiological regulatory mechanism functional under stress conditions. and J. Skotnica ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public