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Start Over Coverage 59-64

2. Astigmatismus oka a jeho vliv na kvalitu vidění

Creator:
Kahounová, Tereza, Černohousová, Tereza, Novák, Jiří, and Novák, Pavel
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
total astigmatism, corneal astigmatism, aberrations, vision quality, visual acuity, celkový astigmatismus, rohovkový astigmatismus, aberace, kvalita vidění, and zraková ostrost
Language:
Czech
Description:
This work describes ocular astigmatism and factors which affect it. Further, total and corneal astigmatism are described and it is analyzed their relationship. An analysis of a diameter of a geometric circle of confusion is performed for the case of defocus and astigmatism. The formulas for modeling fundamental image characteristics of an eye are described. The paper is completed with an example of an experimental analysis of corneal and total astigmatism measured by aberrometry and an analysis of the influence of astigmatism on visual acuity. and V práci je popsána stručně problematika astigmatismu oka a faktorů, které jej ovlivňují. Je charakterizován celkový astigmatismus a tzv. rohovkový astigmatismus. Dále je provedena analýza průměru geometrického rozptylového kroužku na sítnici pro případ defokusace a astigmatismu a jsou popsány vztahy, kterými lze modelovat základní obrazové charakteristiky v důsledku aberací optické soustavy oka. Článek je doplněn příkladem experimentální analýzy astigmatismu při aberometrickém měření a vlivu astigmatismu na zrakovou ostrost.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Decay kinetics of tyrosine radical (YZ*) in chloride anion-depleted photosystem 2 studied by time-resolved EPR

Creator:
Jajoo, A., Bharti, S., and Kawamori, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
bicarbonate, bromide, EPR, fluoride, iodide, nitrate, phosphate, photosystem 2, spinach, tyrosine radical, and sulphate
Language:
Multiple languages
Description:
The decay of tyrosine cation radical was found to be biphasic at 253 K. The fast phase corresponds to the YZ* component while the slow phase corresponds to the tyrosine D radical (YD*) component. At 253 K, the t1/2 value was ∼28.6 s for the fast phase and ∼190.7 s for the slow phase. The fast phase is attributed to the recombination of charges between YZ* and QA-. The activation energy for the reaction of YZ with QA- between 253 and 293 K was 48 kJ mol-1 in Cl--depleted photosystem 2 (PS2) membranes. Both the decay rate and the amplitude of the PAR-induced signal of YZ* were affected by addition of chloride anion. Change in the decay rate and the amplitude of the PAR-induced signal of YZ* was observed when other anions like Br-, I-, F, HCO3-, NO3-, PO43- were substituted in the Cl--depleted PS2. and A. Jajoo, S. Bharti, A. Kawamori.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Photosynthetic responses of apricot (Prunus armeniaca L.) to photosynthetic photon flux density, leaf temperature, and CO2 concentration

Creator:
Wang, F. L., Wang, H., and Wang, G.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
acclimation, compensation and saturation values, intercellular CO2 concentration, net photosynthetic rate, saturation irradiance, stomatal conductance, and transpiration rate
Language:
Multiple languages
Description:
Two cultivars (Katy and Erhuacao) of apricot (Prunus armeniaca L.) were evaluated under open-field and solar-heated greenhouse conditions in northwest China, to determine the effect of photosynthetic photon flux density (PPFD), leaf temperature, and CO2 concentration on the net photosynthetic rate (PN). In greenhouse, Katy registered 28.3 µmol m-2 s-1 for compensation irradiance and 823 µmol m-2 s-1 for saturation irradiance, which were 73 and 117 % of those required by Erhuacao, respectively. The optimum temperatures for cvs. Katy and Erhuacao were 25 and 35 °C in open-field and 22 and 30 °C in greenhouse, respectively. At optimal temperatures, PN of the field-grown Katy was 16.5 µmol m-2 s-1, 21 % less than for a greenhouse-grown apricot. Both cultivars responded positively to CO2 concentrations below the CO2 saturation concentration, whereas Katy exhibited greater PN (18 %) and higher carboxylation efficiency (91 %) than Erhuacao at optimal CO2 concentration. Both cultivars exhibited greater photosynthesis in solar-heated greenhouses than in open-field, but Katy performed better than Erhuacao under greenhouse conditions. and F. L. Wang, H. Wang, G. Wang.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Redescription of Rhabdochona anguillae (Nematoda: Rhabdochonidae), a parasite of eel, Anguilla anguilla, in Europe

Creator:
Saraiva, Aurélia M. and Moravec, František
Format:
print
Type:
model:internalpart and TEXT
Subject:
Rhabdochona anguillae, Nematoda, Anguilla anguilla, and Portugal
Language:
English
Description:
The nematode Rhabdochona anguillae Spaul, 1927, a specific intestinal parasite of the European eel, Anguilla anguilla (L.), is redescribed and illustrated from specimens collected from eels of the Sousa River, northern Portugal (prevalence 20%, intensity 2-13). The species is characterized by the presence of 14 anterior teeth in the prostom, small non-bifurcate deirids, absence of lateral preanal papillae, by the length (0.460-0.660 and 0.130-0.150 mm) and the shape of spicules, fairly large (0.041-0.054 x 0.025-0.030 mm) mature eggs without filaments, and by the bluntly pointed to rounded tip of the tail. Its morphological features are discussed in relation to other congeneric species. This nematode has hitherto been recorded only from eels in southern Europe (Portugal, Spain, Bulgaria).
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Response of bell-pepper (Capsicum annuum L.) to defoliation. Photosynthesis, dry matter and fruit growth

Creator:
Bhatt, R. M. and Srivinasa Rao, N. K.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
The effect of defolíation on net photosynthetic rate (Pn), dry matter production and fruit growth was studied in bell-pepper (Capsicum annuum L. cv. Arka Gaurav). Considerable differences in were observed between defoliated and non-defoliated plants. Defolíation influenced the total dry matter production, leaf area and the relative growth rate of the plants. The bell-pepper has the capacity to compensate photosynthetically for a certain degree of defolíation without reducing the biological yield. No significant differences in the dry matter of fruits per plant were foímd between defoliated and non-defoliated plants.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

7. Steinernema kraussei (Steiner, 1923) (Nematoda: Rhabditida: Steinernematidae): redescription of its topotype from Westphalia

Creator:
Mráček, L.
Format:
print
Type:
model:internalpart and TEXT
Subject:
Steinernema kraussei, redescription, insect, and parasite
Language:
English
Description:
The nematode Steinernema kraussei (Steiner) was rediscovered in the type locality near Neuenherrsee in Westphalia, Germany. This isolate is morphologically identical with that described in 1923 by Steiner. Steiner's original description is completed by these main characters: the head with two circles of papillae, the labial bearing six and the cephalic four papillae; the excretory pore opening of adults is situated far in front of a nerve ring; the male tail has a fine mucron, spicules are on average 49 pm long in first generation, their manubrium having the ratio length to width 1:1 ; spicule retinaculum is usually well developed, gubcmaculum varies in its shape, but mostly is boat-shaped with hooked proximal part. Infective juveniles are 797 to 1102 pm long and their lateral fields have 8 ridges, but the central pair is less distinct and sometimes tends to merge into one unpaired ridge. Since S. kraussei is the oldest, and now the most completely described nematode species in the genus Steinernema, it has to be considered as the type species of this genus. The living culture is presently maintained in several laboratories and all formerly and future described similar species should be compared with this nematode.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public