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Start Over Coverage 75-81

2. Effects of pre-treatment temperature and cap closure on photosynthesis potentialities of potato cultivated in vitro

Creator:
Genoud-Gourichon, G., Veisseire, P., and Coudret, A.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Potato tubers, Solanum tuberosum L. cv. Bintje were stored at 4 or 20 °C. A segment of parenchyma with a bud was cultívated in vitro, in order to study the growth of plantlets according to the storage temperature and the atmosphere composition in vessels. The conservation temperature had no effect on the shoot length, the leaf area and the leaf number. On the other hand, the atmosphere composition in vessels modifíed the morphology. The plantlets cultívated in non-sealed vessels were more developed than the plantlets cultívated in hermetically dosed tubes. The photosynthetic potentíals were 4.7 times higher for the plantlets coming from the tubers stored at 20 °C than for the plantlets coming from the tubers stored at 4 °C. These potentíals were 1.7 times higher when the plantlets were cultívated in non- hermetícally dosed tubes than in hermetically dosed ones. So a conservation of tubers at 20 °C and a culture in non-enclosed vessels seemed to be the suitable conditions for the micropropagation of potatoes in viiro. Moreover, this culture type could improve the acdimatízatíon.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Novel agglutinin in the midgut of the tick Ixodes ricinus

Creator:
Uhlíř, Jan, Grubhoffer, Libor, and Volf, Petr
Format:
print
Type:
model:internalpart and TEXT
Subject:
tick, Ixodes ricinus, midgut, and agglutinin
Language:
English
Description:
Haemagglutination activity (HA) was found and characterized in a midgut homogenate of Ixodes ricinus (L.). HA was induced by tick feeding; it was not detected in starved ticks. In a haemagglutination inhibition test, HA showed an affinity for some carbohydrates (N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, rhamnose, and dulcit) and glycoconjugates (especially lipopolysaccharides). Midgut protein components of 37, 60, 65, and 73 kDa were identified by immunoblotting as potential structural subunits of the new agglutinin.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. On the effect of cross sectional shape on incipient motion and deposition of sediments in fixed bed channels

Creator:
Safari, Mir-Jafar-Sadegh, Mohammadi, Mirali, and Gilanizadehdizaj, Golezar
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
incipient motion, incipient deposition, cross-sectional shape, rigid boundary channel, sediment particles, and critical velocity
Language:
Slovak
Description:
The condition of incipient motion and deposition are of the essential issues for the study of sediment transport. This phenomenon is of great importance to hydraulic engineers for designing sewers, drainage, as well as other rigid boundary channels. This is a study carried out with the objectives of describing the effect of cross-sectional shape on incipient motion and deposition of particles in rigid boundary channels. In this research work, the experimental data given by Loveless (1992) and Mohammadi (2005) are used. On the basis of the critical velocity approach, a new incipient motion equation for a V-shaped bottom channel and incipient deposition of sediment particles equations for rigid boundary channels having circular, rectangular, and U-shaped cross sections are obtained. New equations were compared to the other incipient motion equations. The result shows that the cross-sectional shape is an important factor for defining the minimum velocity for no-deposit particles. This study also distinguishes incipient motion of particles from incipient deposition for particles. The results may be useful for designing fixed bed channels with a limited deposition condition.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Photosynthetic pigments and CO2 exchange in plants of high arctic tundra

Creator:
Gerasimenko, T. V., Korolyova, O. Y., Pilátová, N. I., Popova, I. A., and Kaipianen, E. L.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Maximum values of chlorophyll (Chl) (a + b) content, potentíal (Pp) and net (Pu) photosynthetíc rate in the populatíon of 25 species growing in the tundra of Wrangel Island are presented. Field measurements of response of Pp and P^ to irradiance were doně. Maximum Chl content in arctic plants was typically low [O.S-2.9 g kg'i(f.m.)] and rather close to tíie range characterizing extreme biomes: i.e. deserts and high mountains. By contrast, the sum of carotenoids (Car) was hi^ [1.1-2.3 g kg-i(d.m.)]. In most tundra plants the ratío Chl/Car varied firom 4 to 5. Lower values of Chl/Car were observed only in the high mountain plants of the Paniirs. The peculiarity of pigment apparatus organization in arctic species was expressed in low values of the ratío of pigment-protein complexes LHC/CPl + CP2 dut was mostly close to 1 or lower, as well as in the smáli size of photosynthetíc unit which was 100-200 molecules. Irradiance response of photosynthesis, pigments and structure characteristics indicated features usually considered typical bodi of sun and shade tolerant plants. Their high ability to adapt both to low and high irradiance at low temperature is a substantíal guarantee for 24-h photosyndiesis during polar day.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

7. Stability investigations of rotors mounted on hybrid magnetorheological dampers by the evolutive method

Creator:
Zapoměl, Jaroslav, Kozánek, Jan, and Ferfecki, Petr
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
rigid rotors, controllable damping, hybrid magnetorheological dampers, vibration stability, and evolutive method
Language:
English
Description:
A frequently used technological solution of reducing the time varying forces transmitted between the rotor and its casing is represented by application of a flexible suspension with damping devices added to the constraint elements. To achieve their optimum performance their damping effect must be controllable. For this purpose a concept of a hybrid damping device working on the principle of squeezing the layers of normal and magnetorheological oils have been developed. Here in this article, there is investigated influence of the proposed damping element on stabilty of the rotor vibrations induced by its imbalance during the steady state operating regimes. The stability is assessed by the evolutive method which is based on evaluation of eigenvalues of the system linearized in a small neighbourhood of the rotor phase trajectory and calculation of the corresponding damping ratio or logarithmic decrement. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Životní dráhy prvorodiček po třicítce: proč mít dítě později?

Creator:
Bartošová, Michaela
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
timing of motherhood, mothers after thirty, and qualitative research
Language:
Czech
Description:
The qualitative research is focused on the population of women who had their first child after thirty (in the case of no influence of medical problems that should lead to their prior childlessness) and observes, with the aid of grounded theory, if the women consider their motherhood delayed and how they define the reasons, which caused their having a child at that age. The following paper summarizes some substantial findings from an actual research. As the research has shown, motherhood after thirty is defined by women as both delayed (they became a mother later, than they had primarily intended) and non-delayed (they had a child when they wanted it). The essential criterion for planning and timing of having a child in both cases is the negotiating among partners and (dis)agreement over motivations and expectations of men and women. In general, there is an evident influence of cultural and value changes on timing of motherhood in the Czech Republic, which implicates the change in traditional life cycle and emergence of the new life stage (c. among 20-30 years of life) when young adults remain childless.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public