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15342. Willard S. Boyle: Životopis

Creator:
Boyle, Willard S. and Gregora, Ivan
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Boyle, Willard S., 1924-, osobnosti, fyzici, Nobelova cena (ocenění), nositelé cen a vyznamenání, CCD snímače, celebrities, physics, Nobel Prizes, laureates, CCD scanners, 6, 8, 53, and 929
Language:
Czech
Description:
Portrét kanadského fyzika, který získal v r. 2009 Nobelovu cenu za vynález zobrazovacího polovodičového obvodu - CCD senzoru. and Rubrika: Nobelova cena za fyziku
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

15344. Winter photoinhibition in needles of Taxus baccata seedlings acclimated to different light levels

Creator:
Robakowski, P. and Wyka, T.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
acclimation to irradiance, chlorophyll a fluorescence, photoinhibition, photoprotection, Taxus baccata, and winter hardening
Language:
Multiple languages
Description:
Seasonal variability of maximum quantum yield of PSII photochemistry (Fv/Fm) was studied in needles of Taxus baccata seedlings acclimated to full light (HL, 100% solar irradiance), medium light (ML, 18% irradiance) or low light (LL, 5% irradiance). In HL plants, Fv/Fm was below 0.8 (i.e. state of photoinhibition) throughout the whole experimental period from November to May, with the greatest decline in January and February (when Fv/Fm value reached 0.37). In ML seedlings, significant declines of Fv/Fm occurred in January (with the lowest level at 0.666), whereas the decline in LL seedlings (down to 0.750) was not significant. Full recovery of Fv/Fm in HL seedlings was delayed until the end of May, in contrast to ML and LL seedlings. Fv/Fm was significantly correlated with daily mean (T mean), maximal (T max) and minimal (T min) temperature and T min was consistently the best predictor of Fv/Fm in HL and ML needles. Temperature averages obtained over 3 or 5 days prior to measurement were better predictors of Fv/Fm than 1- or 30-day averages. Thus our results indicate a strong light-dependent seasonal photoinhibition in needles of T. baccata as well as suggest a coupling of Fv/Fm to cumulative temperature from several preceding days. The dependence of sustained winter photoinhibition on light level to which the plants are acclimated was further demonstrated when plants from the three light environments were exposed to full daylight over single days in December, February and April and Fv/Fm was followed throughout the day to determine residual sensitivity of electron transport to ambient irradiance. In February, the treatment revealed a considerable midday increase in photoinhibition in ML plants, much less in HL (already downregulated) and none in LL plants. This suggested a greater capacity for photosynthetic utilization of electrons in LL plants and a readiness for rapid induction of photoinhibition in ML plants. Further differences between plants acclimated to contrasting light regimes were revealed during springtime de-acclimation, when short term regeneration dynamics of Fv/Fm and the relaxation of nonphotochemical quenching (NPQ) indicated a stronger persistent thermal mechanism for energy dissipation in HL plants. The ability of Taxus baccata to sustain winter photoinhibition from autumn until late spring can be beneficial for protection against an excessive light occurring together with frosts but may also restrict photosynthetic carbon gain by this shade-tolerant species when growing in well illuminated sites. and P. Robakowski, T. Wyka.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

15346. With Chinese communists against the Czechoslovak ''Normalization'' regime: exile listy group and its search for political allies against Soviet power domination in central Europe

Creator:
Orság, Petr and Medková, Blanka
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Communist rule, Soviet expansionism, and Radio Peking
Language:
English
Description:
The article investigates how the Holocaust distorted and exploited in Cold War debates on the example of genesis and reception of the book Ghetto Warschau. Tagebücher aus dem Chaos [Warsaw Ghetto: Diaries from Chaos]. The book is a translation of the essay Stosunki polsko-żydowskie w czasie drugiej wojny światowej [Polish-Jewish relations during the Second World War], written by the Jewish historian and creator of the underground archive of the Warsaw Ghetto Emanuel Ringelblum while hiding from the German Occupiers in Warsaw in 1944. Ringelblum addressed his essay to the Polish reader discussing the relation of Christian Poles and Polish Jews under German occupation based on his own experience and the material he had collected. It was originally published in several portions in the Bulletin of the Jewish Historical Institute, an early Holocaust Research Center based in Warsaw. The German translation was based on this publication and published in summer 1967 in a Stuttgart-based publishing house. However, the new title, introduced by its German editors, suggested it was Ringelblum’s diary. Above that the blurb and many footnotes highlighted the role of Poles as perpetrators in the Holocaust, while minimizing that of Germans. As the article shows, the book was prepared by the Göttinger Arbeitskreis ostdeutscher Wissenschaftler [Göttingen Working Group of Eastern German Scholars], a Think Tank with close ties to the German expellee community, campaigning for a revision of the Polish western border. Göttinger Arbeitskries used the book and earlier on excerpts of Ringelblum’s text for a smear-campaign in the West-German expellee press. Through the biased presentation and distorted context of the work these former Ostforschers sought to portrait Poles as eternal anti-Semites and the factual perpetrators of the mass murder of Polish and European Jews following their anti-Polish agenda. Polish nationalist within the ruling Polish United Workers Party in turn exploited the book and the campaign based on it, which coincided with the anti-Semitic campaign in Poland. Though the Institute was not involved in the publication of the German book, the Polish national communists accSome reform Communists who went into exile after the Soviet-led military intervention in Czechoslovakia, in August 1968, began to work in the Listy group led by Jiří Pelikán (1923-1999), a former Director of Czechoslovak Television, the publisher of the Rome-based exile bimonthly Listy, and, later, a Member of the European Parliament. In the search for political allies against Husák’s regime of ''normalization'' (the return to hard-line Communist rule), they tried to establish contact mainly with infl uential representatives of the West European Left. This article, however, examines an area of their involvement in exile, which has previously not received attention - namely, their efforts to develop contacts with Chinese Communists who in the period after August 1968 were vociferously speaking out at international forums and criticizing Soviet expansionism. The author demonstrates how the exiles tried to take advantage of this in order to strengthen their positions as members of the foreign socialist opposition to the normalization regime. When establishing these contacts, they could build particularly upon those that Pelikán had developed in China while working in the International Union of Students. In the second half of the 1970s his erstwhile Chinese colleagues, led by Hu Yaobang (1915-1989), rose to leading positions in the Party, thus creating considerable opportunities for the exiles to work with them. From China, they received continuous funding for their activities, while the Chinese were interested in the Czechoslovak attempt to reform state socialism in the late 1960s. The author acquaints the reader with visits by Listy ‘envoys’ to China, who acquainted their partners there with current developments in central Europe, including information about dissidents and the opposition movement. A special initiative as part of this collaboration was their attempt to get their own representatives involved in the Czech broadcasts of Radio Peking. Though they briefl y succeeded in this, their plan to infl uence the content of transmissions to Czechoslovakia, and thereby make it an information source for listeners which would provide an alternative to state-controlled Czechoslovak mass media, ultimately came to naught: members of the Listy group worked at Radio Peking only as language advisers for the Czech broadcasts. and Překlad: Blanka Medková
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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