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61.
Spruce leaves greened in darkness were devoid of three of the five thermoluminescence bands found for mature leaves. These bands were developed rapidly by exposure of the dark-grown leaves to continuous light. The development of these bands was studied by illumination with repetitive flashes at varied intervals. Flashes at intervals of 1 s were the most effective in inducing these bands. Those at shorter or longer intervals were less effective. It was deduced from these data that the development of these bands is a multiquantum process which involves at least two photo-events with a dark reaction between them. 相似文献
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Vibrio parahaemolyticus was observed to adsorb onto chitin particles and copepods. The efficiency of adsorption was found to be dependent on pH and on the concentration of NaC1 and other ions found in seawater. Highest efficiency was observed in water samples collected from Chesapeake Bay and lowest in water from the open sea. V. parahaemolyticus was found to adborb onto chitin with the highest efficiency of the several bacterial strains tested. Escherichia coli and Pseudomonas fluorescens did not adsorb onto chitin. The adsorption effect is considered to be one of the major factors determining the distribution of this species and affecting the annual cycle of V. parahaemolyticus in the estuarine system. 相似文献
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Chloroplasts isolated from dark-grown seedlings of Picea abiesshowed activities of DCIP and Fecy photoreductions widiout additionof an electron donor to PS-II. In addition to this, when light-inducedoxygen evolution was measured with an oxygen electrode, a significantamount of oxygen was found. These results indicate that thephotoreductions are coupled to the oxygen-evolving reaction.Furthermore, thylakoid membranes were functional in the protonuptake and the 515-nm absorbance change as parameters of theirphysicochemical functions. Electron microscopy showed that thylakoidswere well-developed with prolamellar bodies and partially stackedto from grana. We conclude that oxygen-evolving ability and the physicochemicalfunction of thylakoid membranes develop in chloroplasts of dark-grownspruce seedlings. (Received September 21, 1974; ) 相似文献
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Kume Manabu Nakayama Naoki Iwasaki Yasunari Hori Tomoya Watanabe Shun Terashima Yuki Medo Ayano Arai Nobuaki Yamashita Yoh Mitamura Hiromichi 《Environmental Biology of Fishes》2021,104(4):529-533
Environmental Biology of Fishes - Eel movement patterns have been frequently studied to learn about their movements within the fresh- and brackish waters of the same river before their spawning... 相似文献
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