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Carbonell Ellgutter Jennifer A. Ehrich Dorothee Killengreen Siw T. Ims Rolf A. Unnsteinsdttir Ester R. 《Oecologia》2020,192(2):403-414
Oecologia - Identifying resources driving long-term trends in predators is important to understand ecosystem changes and to manage populations in the context of conservation or control. The arctic... 相似文献
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Previously, eye positions were characterized by the direction of sight, which has two degrees of freedom for conjugate movements and three degrees of freedom for vergent movements. Several groups have recently presented reliable data and unconventional models on binocular coordination, where all three degrees of freedom for one or both eyes have been taken into account. The results illustrate Bernstein's principle that in order to simplify control, the brain establishes unique relations between the target and motor space, in which non-Euclidean geometry of rotations is observed. 相似文献
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Maja Hühns Katrin Neumann † Tina Hausmann Friederike Klemke Wolfgang Lockau Uwe Kahmann Lilya Kopertekh Dorothee Staiger Elfriede K. Pistorius Jens Reuther Eva Waldvogel Wolfgang Wohlleben Martin Effmert Holger Junghans Katja Neubauer Udo Kragl Kerstin Schmidt Jörg Schmidtke Inge Broer 《Plant biotechnology journal》2009,7(9):883-898
The production of biodegradable polymers that can be used to substitute petrochemical compounds in commercial products in transgenic plants is an important challenge for plant biotechnology. Nevertheless, it is often accompanied by reduced plant fitness. To decrease the phenotypic abnormalities of the sprout and to increase polymer production, we restricted cyanophycin accumulation to the potato tubers by using the cyanophycin synthetase gene ( cph ATe ) from Thermosynechococcus elongatus BP-1, which is under the control of the tuber-specific class 1 promoter (B33). Tuber-specific cytosolic (pB33- cph ATe ) as well as tuber-specific plastidic (pB33-PsbY- cph ATe ) expression resulted in significant polymer accumulation solely in the tubers. In plants transformed with pB33- cph ATe , both cyanophycin synthetase and cyanophycin were detected in the cytoplasm leading to an increase up to 2.3% cyanophycin of dry weight and resulting in small and deformed tubers. In B33-PsbY- cph ATe tubers, cyanophycin synthetase and cyanophycin were exclusively found in amyloplasts leading to a cyanophycin accumulation up to 7.5% of dry weight. These tubers were normal in size, some clones showed reduced tuber yield and sometimes exhibited brown sunken staining starting at tubers navel. During a storage period over of 32 weeks of one selected clone, the cyanophycin content was stable in B33-PsbY- cph ATe tubers but the stress symptoms increased. However, all tubers were able to germinate. Nitrogen fertilization in the greenhouse led not to an increased cyanophycin yield, slightly reduced protein content, decreased starch content, and changes in the amounts of bound and free arginine and aspartate, as compared with control tubers were observed. 相似文献
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