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Start Over Coverage 353-360

2. Astronom a rektor prof. PhDr. Jindřich Svoboda

Creator:
Jáchim, František
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Svoboda, Jindřich, 1884-1941, České vysoké učení technické v Praze, astronomie, fyzici, rektoři, astronomy, physicists, rectors, 6, and 53
Language:
Czech
Description:
Astronom a pedagog prof. PhDr. Jindřich Svoboda (1884-1941) patří k významným osobnostem našeho vědeckého a akademického života. Dlouhá léta působil jako profesor na ČVUT, třikrát byl děkanem Vysoké školy speciálních nauk při ČVUT a v akademickém roce 1935/36 stanul jako rektor v čele techniky. Jeho působení především na ČVUT v Praze je spojeno s budováním a rozvojem samostatného vysokého školství nově vzniklého československého státu. V oblasti vědecké je prof. J. Svoboda zakladatelem naší moderní meteoritické astronomie. Do tohoto oboru zavedl vlastní matematické metody zpracování napozorovaných dat a vyvinul řadu pozorovacích metod s využitím jím navržených přístrojů. Přispěl k trvalému rozvoji astronomie malých těles, v níž naše země i dnes zcela vyniká. Prof. J. Svoboda byl uznávanou osobností také v zahraničí. Patřil k nositelům vysokého francouzského vyznamenání Řádu důstojníka Čestné legie., František Jáchim., Součástí článku jsou Svobodovy publikované práce, and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Biphasic regulation of superoxide radical levels in Mn-depleted and photoactivated photosystem II

Creator:
Song, Y.-G., Liu, B., Liu, Y.-P., L.-B., Villamena, F. A., and Liu, Y.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
botanika, botany, biphasic regulation, cyytochrome b559, Mn-depletion, photoactivation, photosystem II, and superoxide radical
Language:
Multiple languages
Description:
In the past decades, it has become clear that superoxide radical (O2 .-) can be generated from photosystem II (PSII) during photosynthesis. Depending on the extent of its accumulation, O2 .- plays an important role in plant physiology and pathology. The photoinhibition/repair cycle is a typical process in PSII which is mainly responsible for the survival of plants under the photoinihibition condition. It is therefore of significant importance to determine O2 .- production in this cycle, and then explore how O2 .- is controlled by PSII within a normal physiological level. With this in mind, we herein investigate the variation of the O2 .- levels in PSII under Mn-depleted and photoactivated conditions mimicking the photoinhibition/repair cycle in vitro. The effect of intrinsic SOD-like component on the O2 .- levels was also studied. Results show that PSII has the ability to regulate the O2 .- levels in these two processes by simultaneously modulating the O2 .- generation activity and intrinsic SOD-like activity. This finding could shed new lights on the photoprotective property of PSII against O2 .- and other reactive oxygen species. and Y. G. Song ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Differential equations in metric spaces

Creator:
Tabor, Jacek
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
differential equation and tangent space
Language:
English
Description:
We give a meaning to derivative of a function u: R → X, where X is a complete metric space. This enables us to investigate differential equations in a metric space. One can prove in particular Gronwall’s Lemma, Peano and Picard Existence Theorems, Lyapunov Theorem or Nagumo Theorem in metric spaces. The main idea is to define the tangent space TxX of x ∈ X. Let u, v : [0, 1) → X, u(0) = v(0) be continuous at zero. Then by the definition u and v are in the same equivalence class if they are tangent at zero, that is if lim h→0+ d(u(h), v(h)) ⁄ h = 0. By TxX we denote the set of all equivalence classes of continuous at zero functions u: [0, 1) → X, u(0) = x, and by T X the disjoint sum of all TxX over x ∈ X. By u (t) ∈ Tu(t)X, where u: → X, we understand the equivalence class of a function [0, 1) h → u(t + h) ∈ X. Given a function F : X → T X such that F(x) ∈ TxX we are now able to investigate solutions to the differential equation u (t) = F(u(t)).
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

5. Diurnal course of quercetin, rutin and phioridzin effect on the activity of the Benson-Calvin cycie 1. Glyceraldehyde-3-phosphate dehydrogenase complex

Creator:
Nazarova, G.N., Muzafarov, E.N., and Lyubimov, V.Yu.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Quercetin, rutin and phioridzin inhibited the activity of glyceraldehyde-3-phosphate dehydrogenase (GPD) complex from spinách leaves. At a concentiation of 5 X 10'5 M they decreased the rate of 3-phosphoglycerate (PGA) leduction by 90, 50- 80 and 30-40 % , respectively. The activity of the effectors depended on the tiine of isolation of enzymes and the corresponding level of endogenic phenolic compounds. To estimate the effect of the last factor, the enzj^e preparation was obtained in the presence and in the absence of insoluble polyvinylpyrrolidone (Polyciar AT). Using rutin it was shown that in the absence of endogenic phenols the inhibition of PGA reduction was decreased as compared with the variant without Polyciar AT. The effect of rutin was constant during the day. On the basis of data obtained the flavonoids are supposed to inhibit the Benson-Calvin cycie at its reducing stage; this effect may be cooperative and depend on quantitative and qualitative content of endogenic phenolic compounds.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public