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762. Ambient levels of UV-B in Hawaii combined with nutrient deficiency decrease photosynthesis in near-isogenic maize lines varying in leaf flavonoids: Flavonoids decrease photoinhibition in plants exposed to UV-B
- Creator:
- Lau, T. S. L., Eno, E., Goldstein, G., Smith, C., and Christopher, D. A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- anthocyanins, chlorophyll fluorescence, CO-assimilation, stomatal conductance, and Zea
- Language:
- Multiple languages
- Description:
- Near-isogenic lines of maize varying in their genes for flavonoid biosynthesis were utilized to examine the effects of foliar flavonoids and nutrient deficiency on maximum net photosynthetic rate (PN) and chlorophyll (Chl) fluorescence (Fv/Fm) in response to ultraviolet-B (UV-B) radiation. Plants with deficient (30 to 70 % lower N, K, Mn, Fe, and Zn) and sufficient nutrients were exposed to four irradiation regimes: (1) no UV-B with solar photosynthetically active radiation (PAR), (2) two day shift to ambient artificial UV-B, 8.2-9.5 kJ m-2 d-1 (21-25 mmol m-2 d-1); (3) continuous ambient artificial UV-B; (4) continuous solar UV-B in Hawaii 12-18 kJ m-2 d-1 (32-47 mmol m-2 d-1). The natural ratio of UVB: PAR (0.25-0.40) was maintained in the UV-B treatments. In the adequately fertilized plants, lines b and lc had higher contents of flavonoids and anthocyanins than did lines hi27 and dta. UV-B induced the accumulation of foliar flavonoids in lines hi27 and b, but not in the low flavonoid line dta or in the high flavonoid line lc. In plants grown on deficient relative to adequate nutrients, flavonoid and anthocyanin contents decreased by 30-40 and 40-50 %, respectively, and Chl a and Chl b contents decreased by 30 and 70 %, respectively. The UV-B treatments did not significantly affect PN and Fv/Fm in plants grown on sufficient nutrients, except in the low flavonoid lines dta and hi27 in which PN and Fv/Fm decreased by ∼15 %. PN, Fv/Fm, and stomatal conductance decreased markedly (20-30 %) in all lines exposed to UV-B when grown on low nutrients. The decrease in Fv/Fm was 10 % less in higher flavonoid lines b and lc. The photosynthetic apparatus of maize readily tolerated ambient UV-B in the tropics when plants were adequately fertilized. In contrast, ambient UV-B combined with nutrient deficiency significantly reduced photosynthesis in this C4 plant. Nutrient deficiency increased the susceptibility of maize to UV-B-induced photoinhibition in part by decreasing the contents of photoprotective compounds. and T. S. L. Lau ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
763. Ameliorating effects of three kinds of antioxidants to ozone-polluted painted nettle (Coleus blumei Benth.)
- Creator:
- Zhang, L., Jia, L. L., Sui, J. X., Wen, M. X., and Chen, Y. J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fluorescence chlorofylu a, výměna plynu, kinetin, Na-askorbát, spermidin, chlorophyll a fluorescence, gas exchange, Na-ascorbate, spermidine, 2, and 581
- Language:
- Multiple languages
- Description:
- Ground concentration of ozone (O3) causes serious threat to plants. In order to protect sensitive plants from O3 pollution, many kinds of antioxidants were assessed in previous studies. In this study, effects of O3 fumigation (a single spike of 120 ± 20 nmol mol-1 for four hours) on an ornamental species (Coleus blumei) was examined in open-top chambers. Before the O3 treatment, plants were sprayed respectively either with a solution of three different antioxidants [Na-ascorbate (NaAsA), kinetin (KIN), and spermidine (Spd)] or with distilled water to compare their protective effects to plants. Our results revealed that O3 fumigation impaired the plasma membrane, decreased chlorophyll (Chl) content, inhibited photosynthesis, induced photoinhibition and photodamage, and caused visible injury. Spraying with KIN, NaAsA or Spd ameliorated the decrease of the Chl content and photosynthetic capability, the impairment of membrane, and visible injury under O3 fumigation. The plants treated with KIN showed the best ability to mitigate the injury caused by O3., L. Zhang, L. L. Jia, J. X. Sui, M. X. Wen, Y. J. Chen., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
764. Ameliorative role of salicylic acid and spermidine in the presence of excess salt in Lycopersicon esculentum
- Creator:
- Fariduddin, Q., Khan, T. A., Yusuf, M., Aafaqee, S. T., and Khalil, R. R. A. E.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- abiotické faktory, antioxidanty, fotosyntéza, abiotic factors, antioxidants, photosynthesis, prolin, kyselina salicylová, spermidin, rajče jedlé, proline, salicylic acid, spermidine, Lycopersicon esculentum, 2, and 581
- Language:
- Multiple languages
- Description:
- Salicylic acid (SA) and polyamines (PA) are widely used to overcome various abiotic stresses including salt (NaCl) stress in plants. In the present investigation, co-application efficacies of SA and PA on the salt stress (200 mM NaCl) were evaluated in Lycopersicon esculentum. After transplantation, at 10-d stage, seedlings were exposed to NaCl through soil and then allowed to grow till 30-d stage. At 31-d stage of growth, plants were sprayed with double distilled water (control) or spermidine (1.0 mM) and/or SA (10-5 M). The salt stress significantly reduced the growth, gas-exchange parameters, but increased antioxidant enzymes and proline content in the leaves. Moreover, the loss caused by salt stress was successfully restored by the following treatment of spermidine and SA., Q. Fariduddin, T. A. Khan, M. Yusuf, S. T. Aafaqee, R. R. A. E. Khalil., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
765. American policy, Korean War, and the lessons of Munich
- Creator:
- Mareš, Petr and Mareš, Jiří
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- historic, Munich agreement, German Sudetenland, Nazi Germany, and Cold War
- Language:
- English
- Description:
- In this article, the author traces how the lessons of the Munich Agreement of September 1938 (on the basis of which Czechoslovakia was forced to cede the predominantly ethnic-German Sudetenland to Nazi Germany) were projected into US foreign policy. In Part One of the essay, based on published sources and unpublished documents from American archives, the topic is covered from the late 1930s to the outbreak of the Korean War (which is discussed in Part Two, to be published in the next issue of Soudobé dějiny). The author looks at immediate American reaction to the North Korean attack on South Korea in June 1950, and then returns to autumn 1938 to test his hypothesis that behind the unusual unity of this reaction was the ingrained negative attitude of the United States to the policy of appeasement. He demonstrates that since the late 1930s the terms ‘Munich’ and ‘appeasement’ have remained forever linked in US policy and US public discourse, and he discusses the transformations of the perception of the two concepts during the Second World War, after the war, and at the beginning of the Cold War. The lessons of Munich, he argues, have drawn on the idealistic as well as the pragmatic sources of US policy, because they stem from the conviction that appeasement is immoral and does not pay. Whereas in Roosevelt’s policy the general lesson was not to allow Hitler’s expansion, Harry S. Truman, Roosevelt’s successor in the White House, had to use the lessons, despite his own self-restraint, to try to counter the steps of a wartime ally, Stalin’s Soviet Union. The Communist take-over in Czechoslovakia in February 1948 and the blockade of the western sectors of Berlin beginning in the summer of that year were important events on this path.The author further considers the infl uence of this factor on the US approach taken in the Korean War in the early 1950s. He seeks to demonstrate that the decision of the Truman Administration to substantially intervene in this confl ict was a direct consequence of the negative attitude to the policy of appeasing an aggressor. This attitude was also shared by the American public, regardless of party affi liation and political sympathies. Arguments based on the rejection of appeasement, however, soon began to be used by the Republicans as ammunition in the election campaign against the incumbent Democrats and the choice of strategy also became a matter of dispute in the choice of strategy on the Korean battlefi eld after China entered the war. Whereas the White House wished to avoid an unlimited confl ict with China, the Commander-in-Chief of the United Nation Command in Korea, General Douglas MacArthur (1880–1964), was in favour of an uncompromising approach and in fact ceased to obey President Harry S. Truman (1884-1972). After being relieved of his command by Truman, MacArthur became the chief critic of his policies and a hero of Truman’s Republican opponents. In spring 1951, the Republicans organized a special Senate committee hearing on the circumstances of MacArthur’s suspension. The author looks in detail at this exceptional clash in post-war US domestic politics, which was meant to be triumphantly used against MacArthur, but gradually changed into a debacle in consequence of, among other things, the compelling testimonies of Secretary of State Dean Acheson (1893-1971) and Secretary of Defense George C. Marshall (1880-1959). In his conclusion, the author seeks to demonstrate how other US presidents returned to the ‘lessons of Munich’, and he argues that these lessons became Truman’s lasting political legacy and as such became fi rmly rooted in American political discourse. and Přeložil: Jiří Mareš
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
766. Americké protiraketové základny v ČR a Polsku z pohledu domácí veřejnosti
- Creator:
- Jan Červenka
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Společenské vědy, výzkum veřejného mínění, public opinion polls, U.S. missile defence, public opinion, Czech Republic, Poland, 18, and 3
- Language:
- Czech
- Description:
- V ČR a Polsku se v posledním období významným zahraničněpolitickým i vnitropolitickým tématem stal záměr vlády USA umístit v těchto zemích některé komponenty budovaného amerického systému obrany proti mezikontinentálním balistickým střelám, který by podle deklarovaného záměru měl chránit kontinentální území Spojených států před případným útokem prostřednictvím menšího počtu raket dlouhého doletu z tzv. „ničemných států“ (rogue states), jak je označuje americká administrativa. Vlády ČR a Polska byly v tomto směru nedávno oficiálně americkou stranou požádány diplomatickou nótou o jednání v této záležitosti. V případě Polska by se mělo jednat o odpalovací zařízení raket určených k ničení mezikontinentálních balistických střel, na českém území by pak měl být dislokován radar, jehož prostřednictvím protiraketový systém vyhledává nepřátelské střely a navádí na ně své rakety. Probíhající diskuse jak uvnitř obou oslovených středoevropských států, tak i na mezinárodním foru zřetelně ukazují, že jak konkrétní plán umístit základny antibalistické obrany v ČR a Polsku, tak zejména samotný záměr budovat byť i jen omezený systém strategické obrany tohoto druhu, představuje závažnou, značně citlivou a kontroverzní otázku s globálním dosahem. Pochopitelný a průběžně sílící zájem o věc projevují také obyvatelé obou zemí. A právě postojům české a polské veřejnosti k celému projektu, jejich aktuálnímu stavu a také možnému dalšímu vývoji se bude věnovat tento text., The text focuses on public opinion in Czech Republic and Poland relating to the plan of U.S. government to locate some parts of U.S. national missile defence in these countries. It describes and compares main shifts of developments of public attitudes in both countries to the project as well as to eventual referendum in this matter within the period up to the first half of 2007. The text shows main demographical, societal and political differences in both countries and discusses reasons and motives behind particular attitudes of Czech and Polish citizens., Jan Červenka., and Seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
767. Američtí Slováci a boj za slovenskou autonomii
- Creator:
- Marek Šmíd
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- 20. století, Slováci, hnutí za nezávislost, exilová politická činnost, Slovaks, autonomy movements, political activities of exiles, Spojené státy americké, Slovensko, United States, Slovakia, 8, and 93/94
- Language:
- Czech
- Description:
- Publikace podle recenzenta přináší zajímavý pohled na slovenský autonomistický proud v meziválečném Československu z dosud nezpracovaného úhlu, a to optikou amerických a kanadských Slováků. Nejedná se pouze o přehledovou práci o slovenském autonomistickém hnutí, nýbrž také o hlubokou sondu do politického, náboženského a kulturního prostředí severoamerických krajanů, jež mělo významný vliv na aktivitu slovenského politického hnutí v první Československé republice. Autor dokumentuje jak vztahy a kontakty politiků na Slovensku s krajanskou obcí v Severní Americe, tak proměny jejích názorů na státoprávní uspořádání Československa a postavení Slováků v něm, které dospěly přes počáteční dílčí rozpory k jednoznačnému autonomistickému stanovisku., This publication, whose title translates as ‘The American Slovaks’ contribution to the movement for an autonomous Slovakia, 1918-38’, provides, according to the reviewer, an interesting view of a trend in inter-war Czechoslovakia seen from the hitherto ignored angle of the Slovaks living in the USA and Canada. This is not only a general survey of the movement for Slovak autonomy; it is also an in-depth examination of the political, religious, and cultural milieux of Slovaks living in North America, which had an important influence on the Slovak political movement in the first Czechoslovak Republic. The author documents the relations between politicians in Slovakia and the Slovak communities in North America, and also discusses the changes in their views on the constitutional arrangement of Czechoslovakia and the Slovaks’ status within it, which led, despite initial conflicts, to a clear autonomist stance., [autor recenze] Marek Šmíd., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
768. AMN 082, an agonist of mGluR7, exhibits mixed anti- and proconvulsant effects in developing rats
- Creator:
- Pavel Mareš
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Experimentální medicína, fyziologie, epileptické záchvaty, ontogeneze, potkan, physiology, epileptic seizures, Rattus norvegicus, ontogeny, metabotropic glutamate receptors (mGlu Rs), uwanted motor efects, 14, and 616-092
- Language:
- English
- Description:
- Metabotropic glutamate receptors (mGluRs) represent a potential therapeutic target. Possible anticonvulsant action of AMN 082, an agonist of mGluR7 subtype, was studied in immature rats using pentylenetetrazol (PTZ)-induced seizures as a model. Five age groups of rats (7-, 12-, 18-, 25-day-old and adult animals) were pretreated with AMN 082 in doses of 0.5, 1, 2, and 5 mg/kg i.p. and 30 min later PTZ was administered (100 mg/kg s.c.). Controls received saline instead of the agonist. AMN 082 did not exhibit clear anticonvulsant action with the exception of suppression of the tonic phase of generalized tonic-clonic seizures (GTCS) in 12-day-old rats. Shorter latencies of GTCS after AMN 082 pretreatment indicate a proconvulsant action. Involuntary movements (mostly tremor) appeared after AMN 082 before PTZ administration, therefore we performed another experimental series with AMN 082 only (1, 2, 5, and 10 mg/kg i.p.). During 60-min observation period tremor appeared in all age groups; sensitivity to this action decreased with age from the 2 mg/kg dose in 7- and 12-day-old rats to the 10 mg/kg dose in adult rats. Mixed anti- and proconvulsant actions of AMN 082 together with unwanted motor effects makes clinical use of this drug highly improbable., Pavel Mareš., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
769. Among the onions and carrots: the “dissident” and the countersignature of post-totalitarianism
- Creator:
- Forsberg, Niklas
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Havel, meaning, power/knowledge, ideology, truth, and authenticity
- Language:
- Czech
- Description:
- This paper explores the notion of “power” prevalent in Václav Havel’s understanding of the post-totalitarian regime. With this notion of power, which is “seeping” in nature, rather than rooted solely in an individual agent’s actions, the role of the individual in the formation of the political “we” becomes a central issue. The starting point is Havel’s well-known example of “the greengrocer,” that illustrate how Havel pictures the way out of the post-totalitarian regime as one in which individuals move from living a lie to living in truth. I show how Havel’s talk about truth and authenticity, and his emphasis on a life in truth (which may appear judgemental, naive and cliché-like) is best understood. The wrong way to understand this is simply to say that people who merely obeyed that government, as the greengrocer did, are to be held accountable because they did not put up a fight against their oppressor. Such an understanding goes wrong because it fails to take into account the complexity of the relationship between power and language. In contrast to this, I argue that the central issue here is not that particular agents are to be held responsible for countersigning messages that they think are false. More precisely, I argue that the moral difficulty here is that the greengrocer’s deeds, which appear as countersignatures of the regime, are possible because the messages conveyed are “innocent” on the surface, in a “literal” sense. The moral dimension of the greengrocer’s actions, aiming to shed light on the complex relation between the government and the individual, is revealed as located in a field of tension between inherited sense and new projections. This, in turn, can help us to see the real nature of the transition Havel’s grocer undergoes when he moves from living a lie to living in truth. It is not a matter of negating a false statement or utterance, nor of replacing it with a true one. It is a matter of realising that the responsibility for meaning is, ultimately, ours – and that the way in which he, the grocer, is one of us is something that has to be earned.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
770. AMPER / OPTONIKA 2011 - navštivte veletrhy budoucích technologií
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public