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3452. Optical properties of the purpie bacterium reaction centres immobilized in polymer film
- Creator:
- Frackowiak, D., Dudkowiak, A., Cegielski, R., Planner, A., and Schulz, C.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- absorption spectrum, bacteriochlorophyll, carotenoid-free mutant, delayed luminescence, fluorescence spectrum, isotropic and stretched films, linear dichroism, photoacoustic spectrum, polyvinyl alcohol film, and Rhodohacter sphaeroides
- Language:
- Multiple languages
- Description:
- Reaction centres (RC) from the purpie bacterium Rhodohacter sphaeroides (strain R-24.1 and carotenoid-free mutant R-26.1) were separated and immobilized in isotropic and stretched polyvinyl alcohol (PVA) films. Absorption, fluorescence, delayed luminescence (8-300 K) and photoacoustic spectra (PAS) of immobilized samples were measured. The RC from wild strain R-24.1 and ffom carotenoid-free mutant R-26.1 were differently oriented in the stretched polymer film. In R-24.1 the long axis of the RC complex was directed under some angle with respect to the perpendicular direction to the PVA film plane, whereas in R-26.1 it was almost perpendicular to this plane. The shapes of linear dichroism (LD) of both strains were different. Delayed luminescence (DL) bands were located in a similar wavelength range as the bacteriochlorophyll and bacteriopheophytin prompt fluorescence bands. Intensity of DL was independent of temperature in the 8-300 K range. The intensity of DL was about three time lower than that of the fluorescence. The dependence of PAS on the frequency of radiation modulation and on the phase shift between modulated acting radiation and measured PAS showed that part of the thermal deactivation was undergoing slowly. Intensity ratio of the slow component to the fast one and/or decay time of the slow component of thermal deactivation were different for various chromophores and for RC ffom the two strains of bacteria.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3453. Ordination of four Belgian sugar beet cultivars as a tool in the detection of ontogenetic photosynthesis modulations: principal component analysis using cytological, anatomical and ecophysiological leaf characteristics
- Creator:
- Boraert, G. and Lemeur, R.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Principal Component Analysis, an ordination technique frequently ušed in phytosociological ecology, has been successfully applied in an attempt to consolidate unknown factors and processes responsible for influencing and modulating photosynthesis determining sugar beet leaf characteristics. Starting from a rough data matrix which consisted of the observed values of 18 cytological, anatomical and ecophysiological leaf parameters, measured in 32 leaf series, this technique calculated the co-ordinates of 32 entities with respect to a whole new set of principál axes. The ordination of all leaf entities was highly correlated with the relative increase of intemal (leaf) area, the total relative stomatal area and the chlorophyll a content. Since their arrangement on the main principál axis was also strongly determined by plant age, the conclusion could be drawn immediately that these three leaf parameters were significantly modulated by plant age. So, conclusions found in a rather subjective way were confirmed by this mathematical ordination technique.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3454. Organisation of photosynthetic apparatus of Triticale in relation to productivity
- Creator:
- Kabanova, S. N., Kabashnikova, L. F., Serduchenko, E. V., Kalituho, L. N., and Chaïka, M. T.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll, genotypes, grain yield, heterosis, hybrids, leaf area, photochemical activity of chloroplasts, plant height, productivity, and seedling length
- Language:
- Multiple languages
- Description:
- Chlorophyll (Chl) content, photochemical activity of chloroplasts as well as photosynthetic and crop productivity were studied in different winter hexaploid Triticale (xTriticosecale Witt.) lines and their F1 hybrids. Heterosis enhanced Chl content, photosynthetic potential, photosynthetic productivity, and grain yield only in several F1 hybrids of Triticale. Indication in some genotypes of close correlations among morphological structure, Chl content, photochemical activity of chloroplasts, photosynthetic potential, and plant productivity may be used in breeding practice of Triticale. and S. N. Kabanova ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3455. Oscillations in photosynthesis and reduction of photosystem 1 acceptor side in sunflower leaves. Functional cytochrome b6/f photosystem 1 ferredoxin-NADP reductase supercomplexes
- Creator:
- Lais, A., Oja, V., Walker, D., and Heber, U.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- CO2 and O2 exchange rates, chlorophyll fluorescence and P700 oxidation (absorption at 830 nm) were recorded in Helianthus amuus L. leaves grown in soil in a growth cabinet. Phase-portraits of CO2 exchange rate plotted against three other parameters were ušed to interpret control of electron transport during photosynthesis oscillations, initiated by transfer from air to the saturating CO2. Plots of the CO2 exchange rate vs. P700 revealed that the P700 part which remained oxidized was almost proportional to CO2 exchange rate during both the ascending and descending phase of oscillations.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3456. Osmotic and atmospheric dehydration effects in the lichens Hypogymnia physodes, Lobaria pulmonaria, and Peltigera aphthosa: an in vivo study of the chlorophyll fluorescence induction
- Creator:
- Jensen, M., Chakir, Samira, and Feige, G. B.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- green algae, NaCl, sucrose, water potential, and water stress
- Language:
- Multiple languages
- Description:
- Inactivation of photosynthesis during atmospheric and osmotic (highly concentrated NaCl or sucrose solutions) dehydration was monitored by measurement of chlorophyll fluorescence induction (OIP-phase, Kautsky-curves) in three lichen species. The induction curves were changed in a very similar way by all three treatments. All dehydration effects were rapidly reversible after rehydration. At relatively mild water stress, the rise time to the transient peak Fp was prolonged, and the variable part of fluorescence was diminished. In addition, at severe water stress, a considerable decline of the F0 value was observed. For NaCl treatment this effect started at water potentials <-8.5 MPa in P. aphthosa, <-12 MPa in H. physodes, and <-21 MPa in L. pulmonaria. Above these water potentials, our observations are in agreement with values from desiccation-tolerant algae, higher plants, and lichens, where an inactivation on the photosystem 2 (PS2) donor side has been postulated. At very low water potentials, the decrease in F0 probably monitors changes in the organization of the antenna apparatus of PS2. and M. Jensen, Samira Chakir, G. B. Feige.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3457. Osobní knihovna Jaroslava Ježka /
- Creator:
- Khel, Richard,
- Type:
- text, katalogy, and soupisy
- Subject:
- Univerzální knihovny. Veřejné knihovny. Soukromé knihovny, Ježek, Jaroslav,, skladatelé, klavíristé, knihovny soukromé, soupisy knih, české a československé knihovny, knižní fondy, Československo 1918-1945, and hudba, tanec, hudební nástroje
- Language:
- Czech and Multiple languages
- Rights:
- unknown
3458. Osudy strahovského rukopisu DF III 1
- Creator:
- Smékalová, Anna
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Dobrovský Josef, Dobner Gelasius, manuscript DF III 1 of the Strahov Library, and Vincencius and Jarloch chronicle
- Language:
- Multiple languages
- Description:
- The DF III 1 Strahov Manuscript, which preserves the only version of the Vincencius and Jarloch chronicle, has a rich and not too happy history behind it. For a long time it was housed in the Prague Chapter Library, from which it was lost under mysterious circumstances sometime before 1764. It was not discovered again until 1826 by Josef Dietrich, curate at Postoloprty, who donated it to Josef Dobrovský. Dobrovský used it for his edition of what is known as the Ansbert Chronicle and then donated it to the Strahov Monastery Library. If we follow the fortunes of the Codex before its disappearance from the Chapter Library, we find that this evidently happened "thanks" to Václav Prokop Duchovský, Secretary to the Archbishop's Consistory, who did not return the borrowed manuscript to its original place, and kept this fact from Gelasius Dobner, who was looking for the Codex in the library a year later in order to compile an edition of both chronicles. The motive for this behaviour was evidently their mutual poor relations due to Dobner's criticism of Hájek's Chronicle.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3459. Osudy strahovského rukopisu DF III 1
- Creator:
- Smékalová, Anna
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- Dobrovský Josef, Dobner Gelasius, manuscript DF III 1 of the Strahov Library, Vincencius and Jarloch chronicle, and PN0441
- Language:
- Multiple languages
- Description:
- The DF III 1 Strahov Manuscript, which preserves the only version of the Vincencius and Jarloch chronicle, has a rich and not too happy history behind it. For a long time it was housed in the Prague Chapter Library, from which it was lost under mysterious circumstances sometime before 1764. It was not discovered again until 1826 by Josef Dietrich, curate at Postoloprty, who donated it to Josef Dobrovský. Dobrovský used it for his edition of what is known as the Ansbert Chronicle and then donated it to the Strahov Monastery Library. If we follow the fortunes of the Codex before its disappearance from the Chapter Library, we find that this evidently happened "thanks" to Václav Prokop Duchovský, Secretary to the Archbishop's Consistory, who did not return the borrowed manuscript to its original place, and kept this fact from Gelasius Dobner, who was looking for the Codex in the library a year later in order to compile an edition of both chronicles. The motive for this behaviour was evidently their mutual poor relations due to Dobner's criticism of Hájek's Chronicle.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3460. Osudy strahovského rukopisu DF III 1
- Creator:
- Smékalová, Anna
- Format:
- electronic
- Type:
- model:article and TEXT
- Subject:
- Dobrovský Josef, Dobner Gelasius, manuscript DF III 1 of the Strahov Library, Vincencius and Jarloch chronicle, and PN0441
- Language:
- Multiple languages
- Description:
- The DF III 1 Strahov Manuscript, which preserves the only version of the Vincencius and Jarloch chronicle, has a rich and not too happy history behind it. For a long time it was housed in the Prague Chapter Library, from which it was lost under mysterious circumstances sometime before 1764. It was not discovered again until 1826 by Josef Dietrich, curate at Postoloprty, who donated it to Josef Dobrovský. Dobrovský used it for his edition of what is known as the Ansbert Chronicle and then donated it to the Strahov Monastery Library. If we follow the fortunes of the Codex before its disappearance from the Chapter Library, we find that this evidently happened "thanks" to Václav Prokop Duchovský, Secretary to the Archbishop's Consistory, who did not return the borrowed manuscript to its original place, and kept this fact from Gelasius Dobner, who was looking for the Codex in the library a year later in order to compile an edition of both chronicles. The motive for this behaviour was evidently their mutual poor relations due to Dobner's criticism of Hájek's Chronicle.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public