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Start Over Coverage 147-153

1. Derivations with power central values on Lie ideals in prime rings

Creator:
Dhara, Basudeb and Sharma, Rajendra K.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
prime ring, derivation, extended centroid, and martindale quotient ring
Language:
English
Description:
Let $R$ be a prime ring of char $R\ne 2$ with a nonzero derivation $d$ and let $U$ be its noncentral Lie ideal. If for some fixed integers $n_1\ge 0, n_2\ge 0, n_3\ge 0$, $( u^{n_1}[d(u),u]u^{n_2})^{n_3}\in Z(R)$ for all $u \in U$, then $R$ satisfies $S_4$, the standard identity in four variables.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Jak mapovat rychlosti molekul

Creator:
Grygoryeva, Kateřina, Poterya, Viktoriya, and Fárník, Michal
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fyzika, molekulární fyzika, ionty, physics, molecular physics, ions, iontové zobrazování, zobrazování rychlostních map, fotodisociace molekul, ion imaging, velocity map imaging, molecular photodissociation, 6, and 53
Language:
Czech and English
Description:
Metody iontového zobrazování a zobrazování rychlostních map (velocity map imaging - VMI) se používají v nejrůznějších oblastech molekulové fyziky a dynamiky. Zaměřili jsme se zejména na studium fotodisociace molekul. V článku přehledně vysvětlíme princip zobrazovacích metod a představíme některé základní experimentální uspořádání a různé metody zpracování snímků. Také je nastíněna metoda detekce pomocí rezonanční ionizace částic umožňující rozlišení kvantových stavů. Na závěr uvedeme jeden příklad studia disociace molekul halogenvodíků na ledových nanočásticích v naší laboratoři a vysvětlíme, jak studované procesy souvisejí s tvorbou ozonové díry., Ion imaging and velocity map imaging (VMI) methods are currently applied in various areas of molecular physics. Here we focus on molecular photodissociation dynamic investigations. The basic principles of VMI methods are explained and essential experimental arragements are introduced as well as various image analyses methods. Resonance ionization methods enabling quantum state resolved detection are also briefly mentioned. Finally, an example from our laboratory is discussed, where hydrogen halide molecules are dissociated onto ice nanoparticles. Such processes are highly relevant for ozone hole generation in the stratosphere above Antarctic., Kateřina Grygoryeva, Viktoriya Poterya, Michal Fárník., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Peculiarities of behaviour of taiga (Ixodes persulcatus) and sheep (Ixodes ricinus) ticks (Acarina: Ixodidae) determined by different methods

Creator:
Alekseev, Andrey N., Jensen, Per M., Dubinins, Helen V., Smirnova, Lioubov A., Makrouchina, Natalia A., and Zharkov, Sergey D.
Format:
print
Type:
model:internalpart and TEXT
Subject:
tick, exoskeleton anomalies, questing, locomotor activity, and Borrelia
Language:
English
Description:
A comparison of the behavioural peculiarities of Ixodes persulcatus Schulze, 1930 (north-western population, Russia) and Ixodes ricinus (L., 1758) from western Russia and Denmark was determined by using two methods. Method 1 involved a sojourn of ticks on vertical plastic slicks and showed that the questing behaviour of /. ricinus nymphs was dependent on temperature and relative humidity (RH). A significantly greater number of nymphs quested at 22°C and 100% RH than at 18°C. When the humidity was reduced to 30% all of the nymphs departed. In the second method, the activity of licks on an inclined “ticksdromc” was estimated. The activity of I. ricinus adults from the Danish population was 1.2 times greater than that of ticks from Russia. Females of the species studied and specimens from all study areas were more active than all other stages of development. The locomotor activity of both adult and immature I. ricinus that were infected with Borrelia burgdorferi sensu lato was suppressed when compared with uninfected specimens. The locomotor activity of I. persulcatus females infected by borreliae with exoskeleton anomalies was 1.3 times greater (PO.05) than that of infected ticks without anomalies. Our data showed that infected females with exoskeleton anomalies could crawl faster on a human and reach uncovered parts of the body that are vulnerable for attachment and feeding. A study of locomotor aclivity and questing behaviour may be useful for comparing the risk for different tick species and populations to transmit tick-borne pathogens.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Use and degradation of light energy in water-stressed Digitalis lanata

Creator:
Fock, H. P., Biehler, K., and Stuhlfauth, T.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
Using ^^C02, ^^02 and H2O gas exchange as weU as metabolite analysis, net CO2 uptake (P]4) and transpiration rate (£) were measured in the water-stressed plants of Digitalis lanata EHRH. The leaf conductance (gcch). the gross CO2 uptake (Pq), Úie photorespiration (Rp) and reassíinilation (RA) rates were calculated from measuied parameters. The pulse modulated fluorescence was measured duiing the steady statě photosynthesis. After withholding iirigation, the leaf water potential decreased to -2.S MPa, but leaves remained turgid and fully exposed to iiradiance even at a severe water stress. Due to the stress-induced reduction of gcch. and E were drastically reduced, whereas Pq and Rp were less affected. Water use efficiency (WUE), which was higher in 1 000 than 350 cm3(C02) increased as the water stress developed. The stomatal closure induced an increase in the reassimilation (RA) of internally liberated CO2 (Rp). The increased CO2 recycling in relation to the water stress was high in 350 cm^(C02) m-^ and still substantial in 1 000 cm3(C02) and consumed a substantial amount of radiant energy in the form of ATP and reduction equivalents. Consequently, the metabolic demand for radiant energy was reduced by less than 40 %, whereas was diminished by more than 70 % in severely stressed plants at 350 cm3(C02) m*3. Additionally, the quantum efiBciency of photosystem 2 as a measure for the flux of photosynthetically generated electrons was reduced upon the stress. This (and possibly other mechanisms) enabled the stressed plants to avoid overreduction of the photosynthetic electron transport chain.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public