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27202. Ole Christensen, Khadija Laghrida Christensen: Approximation theory- From taylor polynomials to wavelets
- Creator:
- Chleboun, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- English
- Description:
- Autor recenze: Jan Chleboun
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27203. Oleg Alexandrovič Lavrentěv a výzkum termojaderné fúze v Sovětském svazu
- Creator:
- Řípa, Milan
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- Lavrent‘jev, Oleg Aleksandrovič, 1926-2011, fyzika, atomová fyzika, physics, atomic physics, Sovětský svaz, Soviet Union, fyzikové, řízená termojaderná fúze, physicists, controlled thermonuclear fusion, lithium-6 deuteride, 6, and 53
- Language:
- Czech and English
- Description:
- Hrdiny exkurze do počátků výzkumu řízené termojaderné fúze netřeba dlouze představovat. Takže stručně. Oleg Alexandrovič Lavrentěv, geniální mladík, iniciátor státem podporovaného výzkumu řízené termojaderné fúze v Sovětském svazu, se ve své kariéře setkal s nechvalně proslulým Lavrentijem Pavlovičem Berijou, vedoucím Zvláštní komise ovládající výzkum atomové energie v Sovětském svazu, s Andrejem Dmitrijevičem Sacharovem, otcem sovětské vodíkové bomby a nositelem Nobelovy ceny za disidentství, a Roaldem Zinnurovičem Sagdějevem, ředitelem Ústavu kosmických výzkumů, profesorem fyziky na Marylandské univerzitě a autorem neoklasické teorie přenosu energie ve vysokoteplotním plazmatu. Článek popisuje jejich setkávání z pohledu obou protagonistů, jen v případě Beriji jeho pohled na Lavrentěva zprostředkoval spisovatel Jurij Muchin., Oleg Alexandrovich Lavrentev initiated research on controlled thermonuclear fusion in the Soviet Union. Likely, he also participated in the use of lithium-6 deuteride as an explosive in the hydrogen bomb. This article confronts Lavrentev’s views on L. P. Beria (the chairman of the Special Commission for Atomic Energy), with impressions of A. D. Sakharov (co-author of the most successful thermonuclear facility tokamak) and R. Z. Sagdeev (a leading theorist of thermonuclear plasma)., Milan Řípa., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27204. Olfactory bulbectomy in methamphetamine-treated rat mothers induces impairment in somatic and functional development of their offspring
- Creator:
- Šlamberová, R., Rudá-Kučerová, J., Babinská, Z., and Ševčíková, M.
- Type:
- article, model:article, and TEXT
- Subject:
- methamphetamine, olfactory bulbectomy, depression, maternal behavior, and development
- Language:
- English
- Description:
- Olfactory bulbectomy in rodents is considered a putative model of depression. Depression is often associated with drug addiction. Our previous studies demonstrated that methamphetamine (MA) administration to rat mothers affects both, mothers and their pups. The aim of the present study was to examine the effect of bulbectomy, as a model of depression, and MA administration on behavior of rat mothers and postnatal development of their pups. Adult female Wistar rats were randomly divided into two groups: bulbectomized (OBX) and sham-operated (SH). A period of 20 days was allowed for the development of the depressive-like phenotype. Animals were tested in the motor activity test and 2 % sucrose preference for anhedonia and hyperactive locomotor response to a novel environment, respectively. After then females were impregnated. Pregnant females were exposed to daily subcutaneous (s.c.) injection of MA (5 mg/kg) or saline (SA) during the entire gestation period. Postnatally, maternal behavior and pup development was examined. The effect of a challenge dose of MA (1 mg/kg, s.c.) on behavior was further examined in adult male offspring. Our results showed no differences in the maternal behavior as a matter of bulbectomy, only OBX rats slept more than all the SH controls. Pups from OBX mothers were born with lower birthweight and gained less weight during the postnatal development than pups from SH controls. Both, bulbectomy and MA administration, delayed the eyes opening. As a matter of functional development of the pups, maternal OBX procedure impaired the performance in the Bar-holding test, but only in saline group. OBX/SA group was the worst in the Bar-holding test relative to all the other groups. In addition, pups from OBX mothers dropped more boluses during the Bar-holding test, suggesting that they were more stressed. In adult male offspring, bulbectomy increased immobility only in the SA/SA group. Prenatal MA exposure increased locomotion, while decreasing immobility. In addition, challenge dose of MA in adulthood increased distance traveled, locomotion, rearing, and average and maximal velocity, while decreasing immobility and grooming. In conclusion, our results suggest that depressive-like phenotype of rat mothers induces impairment in somatic and functional development of their male offspring.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27205. Olfactory bulbectomy induced oxidative and cell damage in rat: protective effect of melatonin
- Creator:
- Tasset, I., Medina, F. J., Peña, J., Jimena, I., Del Carmen Muñoz, M., Salcedo, M., Ruiz, C., Feijóo, M., Montilla, P., and Túnez, I.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, antioxidanty, deprese, melatonin, oxidační stres, antioxidants, depression, oxidative stress, olfactory bublectomy, 14, and 612
- Language:
- English
- Description:
- In this study we analyzed the effects of melatonin (Mel, 1 mg/kg ip) on behavioral changes as well as cell and oxidative damage prompted by bilaterally olfactory bulbectomy. Olfactory bulbectomy caused an increase in lipid peroxidation products and caspase-3, whereas it prompted a decrease of reduced glutathione (GSH) content and antioxidative enzymes activities. Additionally, olfactory bulbectomy induced behavioral changes characterized by the enhancement of immobility time in the forced swim test and hyperactivity in the open field test. All these changes were normalized by treatment of Mel (14 days). Our data show that Mel has a beneficial neuropsychiatric action against oxidative stress, cell damage and behavior alterations., I. Tasset ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27206. Olfactory discrimination between two cryptic species of bats Pipistrellus pipistrellus and P. pygmaeus
- Creator:
- Bartonička, Tomáš, Kaňuch, Peter, Bímová, Barbora, and Bryja, Josef
- Type:
- article and TEXT
- Subject:
- olfactory signal, species-specific recognition, pipistrelles, Vespertilionidae, and Chiroptera
- Language:
- English
- Description:
- Absence of accuracy in species recognition can lead to inter-specific mating and hybridization. Aside from acoustic signals, bats can also use olfactory signals to search for mates. We compared the level of attractiveness of facial glands scents and urinary scents for discrimination in two cryptic bat species. Both sexes of two sympatric bat species Pipistrellus pipistrellus and P. pygmaeus were used as model. Possible sexual preferences using two olfactory signals were studied in a dual choice experiment in a glass Y-maze. Both sexes, without reference to the species, performed lower searching activity in tests with urinary scents than in the case of signals composed of scents of facial glands. Males of both species were able to discriminate and prefer the odour of conspecific females, with small proportion of disassortative choices. Females of both species did not have species-specific preferences. Absence of females’ odour preferences and small proportion of males’ disassortative choices can provide theoretical background for the existence of inter-species hybridization or point at more important role of acoustic signals in pre-mating behaviour.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
27207. Olfactory orientation of the seven-spot ladybird beetle, Coccinella septempunctata (Coleoptera: Coccinellidae): Attraction of adults to plants and conspecific females
- Creator:
- Schaller, Mara and Nentwig, Wolfgang
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinellidae, Coccinella septempunctata, olfaction, attractant, orientation, plant-predator interaction, olfactometer, Berberis vulgaris, and Tripleurospermum inodoratum
- Language:
- English
- Description:
- The olfactory orientation of the aphidophagous ladybird Coccinella septempunctata L. was assessed in a Y-tube olfactometer and a choice arena. The response of the predator to 22 plants, aphid prey and conspecifics was tested. The ladybird was attracted to the odour of chopped Berberis vulgaris L. leaves, and of Tripleurospermum inodoratum (L.) Sch.-Bip. flowerheads, and males were attracted to females. Methanol extracts of B. vulgaris leaves were also attractive.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27208. Olfactory sensitivity in mammalian species
- Creator:
- Wackermannová, M., Pinc, L., and Lukáš Jebavý
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, savci, physiology, mammals, olfaction, sensitivity, odor detection threshold, 14, and 612
- Language:
- English
- Description:
- Olfaction enables most mammalian species to detect and discriminate vast numbers of chemical structures called odorants and pheromones. The perception of such chemical compounds is mediated via two major olfactory systems, the main olfactory system and the vomeronasal system, as well as minor systems, such as the septal organ and the Grueneberg ganglion. Distinct differences exist not only among species but also among individuals in terms of their olfactory sensitivity; however, little is known about the mechanisms that determine these differences. In research on the olfactory sensitivity of mammals, scientists thus depend in most cases on behavioral testing. In this article, we reviewed scientific studies performed on various mammalian species using different methodologies and target chemical substances. Human and non-human primates as well as rodents and dogs are the most frequently studied species. Olfactory threshold studies on other species do not exist with the exception of domestic pigs. Olfactory testing performed on seals, elephants, and bats focused more on discriminative abilities than on sensitivity. An overview of olfactory sensitivity studies as well as olfactory detection ability in most studied mammalian species is presented here, focusing on comparable olfactory detection thresholds. The basics of olfactory perception and olfactory sensitivity factors are also described., M. Wackermannová, L. Pinc, L. Jebavý., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
27209. Oligosaccharide organization on the ß-subunits of pig kidney Na+/K+-ATPase
- Creator:
- Amler, E., Staffolani, R., Baranska, J., Obšil, T., Urbanová, P., Bertoli, E., and Mazzanti, L.
- Type:
- article, model:article, and TEXT
- Subject:
- Na+/K+-ATPase, quartenary structure, forster energy transfer, and ß-subunit
- Language:
- English
- Description:
- The distance between the ß-subunits of Na + /K + -ATPase isolated from pig dark red kidney medulla was determined by Forster energy transfer. First, oligosaccharides of the ß-subunit were shown to be labelled with three fluorophores: Lucifer yellow (LY), Lissamine rhodamine B sulfonyl hydrazine (LRSH) and Cascade blue (CB). Further, LY and LRSFI were used as the donor and the acceptor, respectively, for Forster energy transfer studies to determine the localization of the ß-subunit in the native enzyme which is known to be formed as a tetramer (aß)2. It was found that the ß-subunits in the functional enzyme complex in the membrane are not localized next to each other but are spatially separated. The distance between fluorophores covalently attached to the ß-subunits was found to be 5.1 nm. This conclusion was confirmed by measurements with another donor- acceptor pair CB-LY. The results also support the idea of a direct interaction of the ß-subunit with the extracellular part of the a-subunit. These interactions were modified in the presence of millimolar concentrations of magnesium ions. This indicates a crucial role of magnesium in extracellular interactions between the alpha and beta subunits.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
27210. Olive growing in Slovenian Istria and climatic limitations to its development /
- Creator:
- Ogrin, Darko
- Type:
- text
- Subject:
- klimatologie, klima, pěstování oliv, přehledná zpracování světových dějin (chronologicky), Slovinsko, and vědy o neživé přírodě, přírodní prostředí, astronomie
- Language:
- English
- Description:
- Vliv klimatických podmínek na možnost rozšíření pěstování oliv ve slovinské Istrii.
- Rights:
- unknown