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Start Over Coverage 29-35

2. Analysis of some barley chlorophyll mutants and their response to temperature stress

Creator:
Gálová, E., Böhmová, B., and Ševčovičová, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
fluorescence, heat-shock proteins, Hordeum vulgare, proteins, RNA, and SDS-PAGE
Language:
Multiple languages
Description:
Six barley chlorophyll (Chl) mutants, viridis, flavoviridis, chlorina, xanhta, lutea, and albina, differed in the contents of Chl (a+b) and carotenoids (Cars). In accordance with their Chl-deficient phenotype, the Chl a and b and Car contents of mutants decreased from viridis to albina, only xantha had the same or even higher concentration of Cars as the wild type plant. The albina mutant completely lacked and xantha had a significantly reduced photosynthetic activity. We found quantitative differences in protein contents between wild type and mutant plants, with the lowest concentration per fresh mass in the albina mutant. Chl fluorescence analysis revealed that heat-treated barley leaves of both the wild type and Chl mutants had a lower photosystem 2 efficiency than the untreated ones. With 35S-methionine labelling and SDS-PAGE we found that six to nine de novo synthetized proteins appeared after heat shock (2 h, 42 °C) in the wild type and Chl mutants. In albina the expression of heat shock proteins (HSPs) was reduced to 50 % of that in the wild type. Hence mainly albina mutants, with a completely destroyed proteosynthetic apparatus of the chloroplasts, are able to synthesize a small set of HSPs. The albina mutant is a very useful tool for the study of different gene expression of chloroplast and nuclear DNA. and E. Gálová, B. Böhmová, A. Ševčovičová.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Challenges to the theories of B stars circumstellar environment

Creator:
Krtička, J., Korčáková, D., and Kubát, J.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
stars: winds, stars: outflows, stars: mass-loss, stars: early-type, hydrodynamics, and instabilities
Language:
Czech
Description:
We review recent developments in the field of B stars circumstellar environment modelling and discuss future improvements which are necessary to obtain more realistic models of the circumstellar environment of B stars.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Effects of water stress on photosynthesis and nitrogen metabolism in vegetative and reproductive shoots of Leymus chinensis

Creator:
Xu, Z. Z. and Zhou, G. S.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chlorophyll fluorescence, endopeptidase, glutamate dehydrogenase, glutamine synthetase, lipid peroxidation, nitrate reductase, and soil moisture
Language:
Multiple languages
Description:
In Leymus chinensis, mild water stress (soil moisture 60-65 % of field capacity) had no significant effects on nitrogen metabolism, photosynthesis, and chlorophyll fluorescence. Severe water stress (35-40 %) significantly decreased the activities of nitrate reductase, glutamine synthetase, and glutamate dehydrogenase, net photosynthetic rate, stomatal conductance, transpiration rate, maximal efficiency of photosystem 2 photochemistry (Fv/Fm), actual quantum yield, and photochemical quenching, but increased the endopeptidase activity and malondialdehyde contents. The adverse effects on photosynthesis and N metabolism were markedly greater in reproductive shoots than in vegetative shoots. and Z. Z. Xu, G. S. Zhou.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Experimental determination of the wear of total endoprosthesis polyethylene cup using holographic interferometry

Creator:
Houfek, Martin, Fuis, Vladimír, and Florian, Zdeněk
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
holographic interferometry, total endoprosthesis acetabular cup, and measurement of wear
Language:
English
Description:
This article deals with determining the size of linear wear of acetabulum of total hip endoprosthesis by experimental modelling. The creation of an experimental sample and the equipment to simulate human walking are described in detail. The greatest attention is paid to the method form determining the topography of polyethylene cup and measuring of the loss of polyethylene during the simulation of walking. Holographic interferometry was selected to determine the loss of polyethylene cup on the basis of extensive analysis. Further parts of the article focus on first experience with the application of this method results and other possibilities. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

7. Long-term and seasonal changes in composition and richness of intestinal helminth communities in eels Anguilla anguilla of an isolated English river

Creator:
Kennedy, Clive R.
Format:
print
Type:
model:internalpart and TEXT
Subject:
helminth community, eels, long-term change, diversity, seasonality, and environmental change
Language:
English
Description:
The need for more long-term studies on helminth communities was addressed by examining changes in composition and diversity of the intestinal helminth component and infracommunities in eels of a small isolated river over 12 years. Examination of samples over one summer season indicated that single samples were representative of community richness in that year. In 1985 the community was species poor (1 species only) and with zero diversity, but by 1996 it comprised six species and all parameters at both levels indicated that it was the richest community yet reported from eels. This overall increase in diversity was not regular or uniform from year to year: rather, the general trend could be reversed in any year(s) and variation between years was considerable. The occurrence of many species was erratic and the identity of the dominant species varied between years. The helminth species that colonised the river contributed to helminth species richness and had an impact on community diversity. It is believed that the overall increase in diversity reflects the changing conditions in the habitat and catchment, but the erratic fluctuations in parameters may reflect the size of the river and the absence of any rescue effects. The findings are compared with the few other long-term studies and it is suggested that the extent of the variation over long periods makes it very difficult to use helminths as indicators of other than general environmental changes or to detect short-term changes due to such specific sources as pollution.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Monogeneans of freshwater iishes from cenotes (sinkholes) of the Yucatan Peninsula, Mexico

Creator:
Mendoza-Franco, Edgar F., Scholz, Tomáš, Vivas-Rodriguez, Clara, and Vargas-Vázquez, Joaquin
Format:
print
Type:
model:internalpart and TEXT
Subject:
Monogenea, Ancyrocephalinae, Gyrodactylidae, Cichlidae, Rhamdia, Aslyanax, Gambusia, cenotes, zoogeography, and Mexico
Language:
English
Description:
During a survey of the parasites of freshwater fishes from cenotes (sinkholes) of the Yucatan Peninsula the following species of monogeneans were found on cichlid, pimelodid, characid and poeciliid fishes: Sciadicleithrum mexicanum Kritsky, Vidal-Martinez et Rodriguez-Canul, 1994 from C.ichlasoma urophthalmus (Giinther) (type host), Cichlasoma friedrichsthali (Heckel), Cichlasoma octofasciatum (Regan), and Cichlasoma synspilum Hubbs, all new host records; Sciadicleithrum meekii Mcndoza-Franco, Scholz et Vidal-Martinez, 1997 from Cichlasoma meeki (Brind); Urocleidoides chavarriai (Price, 1938) and Urocleidoides travassosi (Price, 1938) from Rhamdia guatemalensis (Günther); Urocleidoides costaricensis (Price et Bussing, 1967), Urocleidoides heteroancistrium (Price et Bussing, 1968), Urocleidoides anops Kritsky et Thatcher, 1974, Anacanthocotyle anacanthocolyle Kritsky et Fritts, 1970, and Gyrodaclylus neotropicalis Kritsky et Fritts, 1970 from Aslyanax fasciatus; and Gyrodactylus sp. from Gambusia yucatana Regan. Urocleidoides chavarriai, U. travassosi, U. costaricensis, U. heteroancistrium, U. anops, Anacanthocotyle anacanthocotyle and Gyrodactylus neotropicalis are reported from North America (Mexico) for the first time. These findings support the idea about the dispersion of freshwater fishes and their monogenean parasites from South America through Central America to southeastern Mexico, following the emergence of the Panamanian isthmus between 2 and 5 million years ago.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9. Photosynthetic characteristics of Helianthus annuus L. as affected by nitrogenous fertilizers

Creator:
Venanzi, G., Lupattelli, M., Poccheschi, N., and Frenguelli, G.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Considerable increase in net photosynthetic rates ribulose-l-5-bisphosphate carboxylase (RuBPC) and phosphoenolpyruvate carboxylase (PEPC) activities, and pigment contents was observed in Helianthus annuus L. plants affected by different types of N-fertilization, but no cultivar variability was found. and water use efficiency (WUE) were enhanced strongly when the plants were treated with a combined compost (12N-12K-12P) or urea while manure induced a rather weak effect. The carboxylase activities changed wifli the N treatment and they were higly correlated with and WUE (r > 0.9). The RuBPC/PEPC ratios fell drastically in urea and 12N-12K-12P treated plants.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

10. Prediction technique of stability in blade assemblies against subsonic flutter

Creator:
Zinkovskii, A. P. and Tsymbalyuk, V. A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
blade assembly, modeling, airfoil cascade, subsonic flutter, and aeroelastic stability prediction
Language:
English
Description:
The basic principle of the experimental-and-computational technique for predicting the subsonic flutter stability of axial compressor blading are stated. The methodology is described for the experimental determination of non-stationary aerodynamic forces and moments acting on blades during their in-flow vibrations; the calculation of the dynamic stability of a blade assembly against flutter; the aerodynamic rig design and peculiar features of its components to perform testing of airfoil cascades. The results of testing of the developed experimental-and-computational complex are presented. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public