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34532. Variace na Korán: Islám v diaspoře
- Creator:
- Bielický, Viktor
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34533. Variační počet, přirozený aparát fyziky
- Creator:
- Musilová, Jana and Musilová, Pavla
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- variační počet, variační metody, physics, calculus of variations, variational methods, matematická estetika, variační matematika, variační fyzika, 6, and 53
- Language:
- Czech and English
- Description:
- Říká se, že jedním ze znaků správné fyzikální teorie je její krása. Máme-li na mysli estetičnost matematickou, patří variační počet k matematickým metodám, které naplňují tento požadavek vrchovatě. Je také pravda, že správné (zkušeností a experimentem prověřené) fyzikální teorie bývají variační, tj. odvoditelné z variačního principu: Klasická mechanika, relativistická mechanika, kvantová mechanika, klasická elektrodynamika... Na zcela elementární úrovni předkládáme základní myšlenku a klasické postupy variačního počtu, s ukázkami použití v geometrii a fyzice. Zaměříme se pouze na variační princip prvního řádu, s důrazem na mechaniku, kde na rozdíl od teorie pole závisí řešené úlohy pouze na jedné nezávisle proměnné, ve fyzice obvykle na čase., It is said that one of the characteristic features of physical theories is their beauty. Having in mind the "mathematical aesthetic appearance" one can say that the calculus of variations highly fulfils this requirement! It is also well known that correct physical theories (those verified experimentally), are often variational, i.e. based on a variational principle: classical mechanics, relativistic mechanics, quantum mechanics, classical electrodynamics, etc. We present, at a very basic level, the fundamental ideas and classical approaches of the calculus of variations, including examples of their use in geometry and physics. We focus on the first order variational principle, emphasizing mechanics, because contrary to field theories, the variational problems in mechanics depend on one independent variable only (usually time in physics)., Jana Musilová, Pavla Musilová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34534. Variation in carbonic anhydrase activity and its relationship with photosynthesis and dry mass of mustard
- Creator:
- Khan, N.A.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Carbonic anhydrase (CA) activity and net photosynthetic rate (/’N) in the leaves, and plant dry mass (DM) in twelve cultivars of mustard (Brassica juncea L.) were measured 50, 70 and 90 d after sowing. At different sampling stages CA was strongly associated with PN and DM.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34535. Variation in CDKAL1 gene is associated with therapeutic response to sulphonylureas
- Creator:
- Zbynek Schroner, Martin Javorský, Halušková, J., Klimčáková, L., Babjaková, E., Fabianová, M., Slabá, E., Kozárová, M., and Ivan Tkáč
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, pharmacogenetics, sulphonylureas, CDKAL1, glycemic control, type 2 diabetes, 14, and 612
- Language:
- English
- Description:
- The aim of the present pilot pharmacogenetic study was to analyse quantitative effects of sulphonylurea treatment in addition to metformin on parameters of glycemic control with respect to CDKAL1 genotypes in patients with type 2 diabetes. Effect of 6-month sulphonylurea therapy on glycemic control according to CDKAL1 genotypes was evaluated in 101 patients with type 2 diabetes who failed to achieve glycemic control on metformin monotherapy. CDKAL1 rs7756992 polymorphism was determined by melting curve analysis of small amplicon following real-time PCR. After sulphonylurea treatment fasting plasma glucose (FPG) levels were significantly different (p=0.045) among three CDKAL1 genotype groups (AA: n=49; AG: n=36; GG: n=16). In a dominant genetic model, carriers of the G-allele (AG+GG, n=52) achieved significantly lower FPG levels in comparison with patients with the AA genotype (6.90±1.08 vs. 7.48±1.12 mmol/l, p=0.013). Consequently, adjusted ΔFPG was significantly higher in the AG+GG compared to the AA group (1.48±1.51 vs. 1.02±1.33 mmol/l, p=0.022). Similar trend was observed for HbA1c levels, but the difference between the genotype groups did not reach the level of statistical significance. Relatively small number of included patients is a limitation of the present study. In conclusion, our results suggest that the magnitude of FPG reduction after 6-month sulphonylurea treatment in patients with type 2 diabetes is related to the variation in CDKAL1., Z. Schroner ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34536. Variation in leaf photosynthetic characteristics in wild rice species
- Creator:
- Kiran, T. V., Rao, Y. V., Subrahmanyam, D., Rani, N. S., Bhadana, V. P., Rao, P. R., and Voleti, S. R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, gas exchange, rice, specific leaf area, specific leaf mass, stomatal conductance, wild rice, 2, and 581
- Language:
- Multiple languages
- Description:
- Variations in leaf gas-exchange characteristics, leaf pigment content, and other important leaf traits were investigated in seven wild Oryza species, five hybrids, and five improved varieties. The significant variations were observed in photosynthetic pigment contents amongst different species of Oryza. The mean chlorophyll (Chl) content was higher in O. sativa (varieties and hybrids), while O. eichengeri showed the lowest Chl content. The mean carotenoid (Car) content in O. sativa (varieties and hybrids) was higher than in other wild rice species. O. eichengeri and O. barthii had significantly lower Car contents than other rice species. Significant differences were noticed in the rate of photosynthesis (PN), stomatal conductance (gs), transpiration rate (E), internal CO2 concentration (Ci), specific leaf mass (SLM), and leaf thickness amongst different Oryza species. The mean PN was the highest in O. nivara followed by O. eichengeri. The mean PN was the lowest in O. glumaepatula, which was lower than that of cultivated varieties and hybrids of O. sativa. High rates of photosynthesis were observed in O. nivara (ACC. No. CR 100097), O. rufipogon (ACC.No. CR 100267), and O. nivara (ACC.No. CR 100008). The O. nivara and O. rufipogon genotypes with high PN might be used in rice improvement programmes for an increase of leaf photosynthesis in rice. Multiple correlations performed between different gas-exchange characteristics and other physiological traits revealed that the rate of photosynthesis was not dependent on the leaf pigment content or the leaf thickness. A strong positive correlation between PN and the PN/Ci ratio, which represents the carboxylation efficiency, indicated that the observed variation in PN was not based on pigment content or other leaf traits. and T. V. Kiran ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34537. Variation in parameters affecting risk of human disease due to TBE virus
- Creator:
- Korenberg, E. I. and Kovalevskii, Yu V.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- tick-borne encephalitis, Ixodes persulcatus, and risk of infection
- Language:
- English
- Description:
- To rank variables affecting risk of human disease due to tick-borne encephalitis (TBE) virus in the Russian Far East, we compared annual changes in ( 1 ) frequency of human contact with vector ticks, (2) prevalence of infection in the tick population and (3) quantity of virus present infected ticks. Sites were sampled uniformly over a 4-year period in a forested region where Ixodes persulcatus serves as the principle vector. The questing density of ticks on vegetation remained relatively constant during the course of this study. The frequency of contacts of the local human population with ticks carrying different doses of the TBE virus was changeable. The rate of TBE infection of humans in the study site corresponded to that of human contacts with highly infected ticks. The density of highly infected ticks represents the principal parameter for determining potential epidemiological significance of a natural TBE focus.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34538. Variation in photosynthetic characteristics and leaf area contributes to Spathiphyllum cultivar differences in biomass production
- Creator:
- Wang, Qibing and Chen, Jianjun
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- biomass, chlorophyll content, intercellular CO2 concentration, leaf area and thickness, net photosynthetic rate, ornamental foliage plants, peace lily, stomatal conductance, and water-use efficiency
- Language:
- Multiple languages
- Description:
- Three genetically related Spathiphyllum cultivars, Claudia, Double Take, and Petite with similar initial sizes and biomass, were grown in a shaded greenhouse and fertilized with a constant supply of nitrogen at 200 g m-3 using an ebb-and-flow fertigation system. Seven months later, Claudia and Double Take had plant sizes and biomasses significantly greater than Petite. Stomatal conductances of Claudia and Double Take were 30 % greater, thus net photosynthetic rates (PN) were significantly higher than in Petite. In addition, the leaf areas (LA) of Claudia and Double Take were 60 % larger than of Petite. Since PN was expressed per leaf surface area, the greater the LA was, the more CO2 was fixed. Thus, the differences in plant size and biomass production of Claudia and Double Take compared to Petite are attributed to high PN and increased LA. and Qibing Wang, Jianjun Chen.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34539. Variation in photosynthetic rates and biomass productivity among four mulberry cultivars
- Creator:
- Chaitanya, K. V., Masilamani, S., Jutur, P. P., and Ramachandra Reddy, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- branches, chlorophyll, DCPIP photoreduction, glucose, Morus, ribulose-1,5-bisphosphate carboxylase, shoot, starch, sucrose, and sucrose phosphate synthase
- Language:
- Multiple languages
- Description:
- Among four mulberry (Morus alba L.) cultivars (K-2, MR-2, BC2-59, and S-13), highest net photosynthetic rate (PN) was observed in BC2-59 while the lowest rates were recorded with K-2. Significant differences among the four cultivars were found in leaf area, biomass production, activities of ribulose-1,5-bisphosphate carboxylase and sucrose phosphate synthase, and glucose and sucrose contents. The PN and the activities of photosynthetic enzymes in the four cultivars were significantly correlated with the growth and biomass production measured as leaf yield, total shoot mass, and aerial plant biomass. and K. V. Chaitanya ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
34540. Variation in structural and physiological leaf traits of eight species in karst desertification area of China
- Creator:
- Wei, L.-Y., Zeng, D.-J., Lv, S.-H., Zhang, J.-L., Jiao, J.-F., You, Y.-M., and Li, X.-K.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, desertification, dry biomass, karst area, leaf area, photosynthesis, and specific leaf area
- Language:
- Multiple languages
- Description:
- Leaf traits have long been recognized as influential factors in the acquisition and processing of resources by plants. However, there is less knowledge of between-species variations in seasonal changes in leaf traits and trait interrelationships. Therefore, we examined variations in leaf area (LA), dry biomass (DM), specific leaf area (SLA), and leaf gas-exchange parameters in one non-native and seven native tree species under field environmental conditions, in a karst area in China subjected to desertification. Measurements were taken three times during the growing season. The results show that the seven native trees had higher LA, DM, and water-use efficiency (WUE) than the non-native Cinnamomum camphora. In contrast, all the native tree species except Ligustrum lucidum had lower photosynthetic rates (PN) than the non-native species. In all species, the relationship between LA and DM was less variable than the relationship between SLA and LA. However, leaves of the non-native C. camphora and native species Sterculia lanceolata, Cleidiocarpon cavalerei and Cyclobalanopsis glauca were highly sensitive to seasonal conditions, leaves of Sapindus mukorossi and Ligustrum lucidum were less sensitive to seasonal changes, and leaves of Syzygium cumini and Cephalomappa sinensis were insensitive. An understanding of leaf traits will aid the selection of suitable species for land restoration. and L.-Y. Wei ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public