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Gerald Mayr 《Ibis》2013,155(2):384-396
A new fossil stem group representative of Coliiformes (mousebirds) with a remarkable skull morphology is described from the late Oligocene of Germany. Oligocolius psittacocephalon sp. nov. for the first time preserves the skull of a post‐Eocene fossil mousebird. This exhibits a combination of skull features unknown from any other bird and converges on the skull of parrots in that the beak is separated from the cranium by a marked nasofrontal hinge and in that the interorbital part of the frontal bones is very wide. In addition, the mandible of the new species exhibits long retroarticular processes, which are unexpected because unlike in other coliiform birds exhibiting this feature, the short beak was probably not used for probing in substrate. It is hypothesized that the retroarticular processes of O. psittacocephalon instead served for a particular wide and forceful opening of the beak. Eight large fruit stones are situated in the area of the digestive tract of the new species. Preservation of most of these in a well‐delimited cluster in the region of the upper oesophagus suggests that, unlike in modern mousebirds, O. psittacocephalon had a crop. The new fossil shows that late Oligocene European stem group Coliiformes significantly differed from their extant relatives in morphology and probably also in feeding ecology. 相似文献
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The contents of 15 different phenolic compounds in apple leaves and fruit skin from various orchards were determined by HPLC. High concentrations of flavan-3-ols were found in those orchards which were not infected by Venturia inaequalis . This observation corroborates earlier findings on different cultivars. The hypothesis that these compounds could be involved in the resistance of apple to scab was tested by inhibiting the key enzyme of the phenol biosynthesis, the phenylalanine-ammonia-lyase, in young shoots of the resistant genotype 'Sir Prize'. After inoculation of the inhibitor-treated leaves, severe symptoms of the disease occurred. The fungal infection was confirmed by histological studies. No flavonal-accumulation could be observed at the infection site which was the case in the non-inhibited but inoculated controls. 相似文献
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The karyotype of the perch (Percafluviatilis L.) was analysed by means of silver-staining, the chromomyc in A/3 Distamycin A/DAPI and Actinomycin D fluorescence technique
in order to locate active NORs and to selectively highlight certain heterochromatic regions. The ribosomal RNA genes are localized
at the secondary constrictions of the short arms of chromosomes no. 16. Additionally, bright chromomycin fluorescence was
observed in the same regions. No DAPI/ Distamycin A bright heterochromatic block was detected in the perch karyotype. 相似文献
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Susanna Lladó Maldonado Peter Panjan Shiwen Sun Detlev Rasch Adama M. Sesay Torsten Mayr Rainer Krull 《Biotechnology and bioengineering》2019,116(1):65-75
A new disposable, multiphase, microbioreactor (MBR; with a working volume of 550 μl) equipped with online sensors is presented for biotechnological screening research purposes owing to its high-throughput potential. Its design and fabrication, online sensor integration, and operation are described. During aerobic cultivation, sufficient oxygen supply is the most important factor that influences growth and product formation. The MBR is a microbubble column bioreactor (μBC), and the oxygen supply was realized by active pneumatic bubble aeration, ensuring sufficient volumetric liquid-phase mass transfer (k L a) and proper homogenization of the cultivation broth. The μBC was equipped with miniaturized sensors for the pH, dissolved oxygen, optical density and glucose concentration that allowed real-time online monitoring of these process variables during cultivation. The challenge addressed here was the integration of sensors in the limited available space. The MBR was shown to be a suitable screening platform for the cultivation of biological systems. Batch cultivations of Saccharomyces cerevisiae were performed to observe the variation in the process variables over time and to show the robustness and operability of all the online sensors in the MBR. 相似文献
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