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2. Chlorophyllase: occurrence, functions, mechanism of action, effects of external and internal factors
- Creator:
- Dražkiewicz, M.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Chlorophyliase (Chlase) is widely distributed in higher and lower plants and differs in activity. It occurs in various organs. In some plants the enzyme is synthesized in cytoplasm, in others in chloroplasts. Various Chlase forms are known. Participation, in the chlorophyll (Chl) degrading systém belongs to the main fimctions of Chlase. Moreover, it may catalyse Chl biosynthesis and takés part in photosynthesis. The Chlase activity is stimulated by radiant energy, sublethal freezing, heavy metals (Hg, Zn, Cu), Fe and Mn deficiency, and mosaic virus infection. The effect of water content on Chlase activity depends on individual plant organs. Osmotic and saline- osmotic stress decreases Chlase activity, but NaCl can stimulate the activity. The influence of plant age depends on plant genus. Some growth regulators (ethylene, heteroauxin, abscisic acid) increase Chlase activity, others (kinetin, dicarboxylic monoesters, gibberellic acid, gibbérellin A3) inhibit it. The mechanisms of Chlase action are also reviewed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Epistemologies of spaces and places: an introduction
- Creator:
- Hladík, Radim
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- prostor (filozofie), místo (filozofie), teorie poznání, space (philosophy), place (philosophy), geoepistemologie, místní vědění, geografie vědy, epistemology, geoepistemology, local knowledge, geography of science, 5, and 11
- Language:
- Czech
- Description:
- The article introduces a special themed issue of Theory of Science on epistemologies of spaces and places. It provides a disciplinary context of the theme and reviews some of the key arguments that led to the so-called spatial turn in social sciences and the humanities. Science studies in the broad sense (including social studies of science and technology, history and philosophy of science) have also been affected by this shift of research interest to spatial aspects of science at both micro- and macro-levels. Scientific knowledge has been subject to analyses that stress its local contingencies, mobility and dependencies on spatial arrangements. The ensuing new epistemologies require novel concepts or reconsideration of the older terms, such as universality or objectivity., Tento článek uvozuje zvláštní tematické číslo Teorie vědy věnované epistemologiím prostorů a míst. Článek představuje oborový kontext tématu a poskytuje přehled některých klíčových argumentů, jež vedly k takzvanému prostorovému obratu v sociálních a humanitních vědách. Výzkumy vědy v širokém smyslu (zahrnujícím sociální výzkumy vědy a techniky, dějiny a filosofii vědy) byly také ovlivněny tímto přesunem badatelských zájmů k jejím prostorovým aspektům na mikro i makro úrovni. Vědecké vědění je podrobováno analýzám, které zdůrazňují jeho místní nahodilosti, mobilitu a závislost na prostorových uspořádáních. Následné nové epistemologie vyžadují nové koncepty či přehodnocení starších termínů, jako univerzalita a objektvita., and Radim Hladík.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Experimental microsporidiosis in immunocompetent immunodeficient mice and monkeys
- Creator:
- Didier, E.S., Varner, P.W., Didier, P.J., Aldras, A.M., Millichamp, N.J., Murphey-Corb, M., Bohm, R., and Shadduck, J.A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Microsporidia, AIDS, opportunistic infection, Nosema, Encephalitozoon, encephaiitozoonosis, and microsporidiosis
- Language:
- English
- Description:
- Microsporidia cause opportunistic infections in AIDS patients and commonly infect laboratory animals, as well. Euthymie C57B1/6 mice experimentally infected with intraperitoneal injections of lxlO6 Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923, Encephalitozoon hellem Didier et al., 1991, or Nosema comeum Shadduck et al., 1990 displayed no clinical signs of disease. Athymic mice, however, developed ascites and died 8-16 days after inoculation with N. comeum, 21-25 days after inoculation with E. cuniculi, and 34-37 days after inoculation with E. hellem. All athymic mice displayed hepatomegaly, dilated intestine and accumulation of ascites fluid. Granulomatous lesions were primarily located in the liver, lung, pancreas, spleen, and on serosal surfaces of abdominal organs.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Fantastično, váhání a víra
- Creator:
- Zuska, Vlastimil
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech and English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. K přímé řeči z hlediska kvantitativního (v českých textech uměleckého stylu)
- Creator:
- Těšitelová, Marie
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech and English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Kostnický Šimon od sv. Štěpána a Summa recreatorum
- Creator:
- Vidmanová, Anežka
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Summa recreatorum and Simon of Constance from St Stephen's
- Language:
- Multiple languages
- Description:
- This article is the first to publish a versified pamphlet with the incipit De sancto Stephano Symon celebro male sano (Walther, Initia, no. 4155). The author sees in its 166 verses two pamphlets: the first targets a Constance priest from St Stephen's, Simon Lind, and was evidently composed in Constance some June after 1300, while the second targeting an unknown Simon, was composed some 18th October. The author believes that this double-pamphlet was included in Summa recreatorum by its unknown author, who was perhaps working to the order of Albrecht of Šternberk, as part of the struggle between himself and Petr Jelito for the favour of Charles IV and the associated ecclesiastical posts. The Summa was not drawn up for the death of Charles, soon after which followed that of Albrecht of Šternberk. Hence its ongoing composition must be put down to the 1370s.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. Micro-PIV characterization of laminar developed flows of Newtonian and non-Newtonian fluids in a slit channel
- Creator:
- Completo, Carlos, Geraldes, Vitor, and Viriato, Semião
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- micro-PIV, slit, channel, non-Newtonian, blood analogue, xanthan, and laminar
- Language:
- English
- Description:
- Comprehensive knowledge of hydrodynamics inside the feeding channels of spira-lwound membrane modules is recognized as crucial for the efficient operation of such separation equipments. Slits are laboratory models widely used to mimic the fundamentals of hydrodynamics and mass transfer in spiral-wound membrane modules. In this work micro-PIV was the technique chosen to characterize fully developed laminar flows in a slit for both Newtonian and non-Newtonian fluids. Experiments with water, water-glycerol and water-glycerol-xanthan were carried out at different flow rates, ranging from 4.3. to 25.3 L/h. The ternary mixture water-glycerol-xanthan simulates the non-Newtonian rheological behavior of blood. The other fluids are Newtonian and exhibit different viscosities. The fluids rheology was characterized making recourse to a viscometer. Using micro-PIV, velocity maps at several depths of the channel were obtained. As expected, results showed that the Newtonian fluids flows exhibit parabolic profiles typical of laminar developed flows in slits. On the other hand, slightly flattened profiles characterize the non-Newtonian fluid flows. Comparisons with the analytical solutions for laminar developed flows in rectangular slits are very encouraging. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Okazionalismy v současné české publicistice
- Creator:
- Staněk, Vladimír
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Robustní metody v hydrologii a vodním hospodářství. Část 1. Metody výzkumu
- Creator:
- Nacházel, Karel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- uncertainty, stability, robustness, modern control theory, dynamic systems, controller, mathematical describing of dynamic systems, synthetic flood wave, flood protection effect of reservoir, runoff regulation, neurčitost, stabilita, robustnost, moderní teorie řízení, dynamické systémy, regulátor, matematický popis dynamických systémů, syntetická povodňová vlna, ochranný účinek nádrže, and regulace odtoku
- Language:
- Slovak
- Description:
- This study deals with uncertainty, stability and robustness in reservoirs operation. These properties of control currently represent a new aspect in the utilization of water resources and their systems in changing conditions. The study is based on the modern control theory of dynamic systems. It also explains the aims and exacting nature of methodical approaches. Instead of analytical methods, simulation models were used for the solution of runoff stability during different flood situations. The flood protection effect of the reservoir was solved on the basis of a set of generated synthetic flood waves. Then, the stability of the runoff was investigated in different hydrological situations. The study concludes that the stability of the runoff from the reservoir is possible to reach only within certain limits, while in a catastrophic flood situation, it is unrealistic. It also concludes that the combination of different flood protection measures is purposeful, e.g. a larger flood-control storage, predischarge, intensification of the hydrometeorological forecast, stream-channel regulation, etc. Finally, the study suggests themes for further investigation in this field. and Studie se zabývá neurčitostí, stabilitou a robustností při operativním řízení nádrží. Tyto vlastnosti řízení se dnes stávají novými hledisky při využívání vodních zdrojů a jejich soustav v měnících se podmínkách. Studie vychází z moderní teorie řízení dynamických systémů, objasňuje její cíle a matematickou náročnost metodických postupů. Místo analytických metod byly ve studii využity pro řešení stability odtoku z nádrží za povodňových situací simulační modely. Ochranný účinek nádrže se řešil variantně na podkladě souborů generovaných syntetických povodňových vln. Stabilita odtoku se tak mohla zkoumat v různých hydrologických situacích. Studie dospěla k závěru, že stabilitu odtoku u vybudovaných nádrží lze zabezpečit zpravidla jen v jistých mezích, v katastrofálních situacích je tento požadavek nereálný. Účelná je tu kombinace různých protipovodňových opatření, např. většího ochranného prostoru nádrže, předvypouštění z nádrže, prohloubení hydrometeorologické předpovědi, úpravy koryta pod nádrží a j. Studie uvádí v závěru náměty na další výzkum v této oblasti.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public