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排序方式: 共有355条查询结果,搜索用时 15 毫秒
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Tobias J. Legler Zhong Liu Ariadni Mavrou Kirstin Finning Ilona Hromadnikova Silvia Galbiati Cathy Meaney Maj A. Hultén Francesco Crea Martin L. Olsson Deborah G. Maddocks Dorothy Huang Sylvia Armstrong Fisher Markus Sprenger-Haussels Aicha Ait Soussan C. Ellen van der Schoot 《黑龙江环境通报》2007,27(9):824-829
Objective Cell free foetal DNA (cff DNA) extracted from maternal plasma is now recognized as a potential source for prenatal diagnosis but the methodology is currently not well standardized. To evaluate different manual and automated DNA extraction methods with a view to developing standards, an International Workshop was performed. Methods Three plasma pools from RhD-negative pregnant women, a DNA standard, real-time-PCR protocol, primers and probes for RHD were sent to 12 laboratories and also to one company (Qiagen, Hilden, Germany). In pre-tests, pool 3 showed a low cff DNA concentration, pool 1 showed a higher concentration and pool 2 an intermediate concentration. Results The QIAamp DSP Virus Kit, the High Pure PCR Template Preparation Kit, an in-house protocol using the QIAamp DNA Blood Mini Kit, the CST genomic DNA purification kit, the Magna Pure LC, the MDx, the M48, the EZ1 and an in-house protocol using magnetic beads for manual and automated extraction were the methods that were able to reliably detect foetal RHD. The best results were obtained with the QIAamp DSP Virus Kit. The QIAamp DNA Blood Mini Kit showed very comparable results in laboratories that followed the manufacturer's protocol and started with ≥ 500 µL plasma. One participant using the QIAamp DNA Blood Midi Kit failed to detect reliably RHD in pool 3. Conclusions This workshop initiated a standardization process for extraction of cff DNA in maternal plasma. The highest yield was obtained by the QIAamp DSP Virus Kit, a result that will be evaluated in more detail in future studies. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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E. Tobias Krause Christoph Brummel Sarah Kohlwey Markus C. Baier Caroline Müller Francesco Bonadonna Barbara A. Caspers 《Behavioral ecology and sociobiology》2014,68(11):1819-1827
Although birds have recently been shown to possess olfactory abilities and to use chemical cues in communication, limited effort has been made to demonstrate the use of odorants in social contexts. Even less is known regarding the use of odorants in species recognition. The ability to recognize conspecifics should be more pronounced in social species. This study investigated the importance of olfactory cues in species recognition in females of two estrildid finch species with different levels of sociality. Combining odor preference tests with chemical analyses, we surveyed whether female zebra finches and diamond firetails are able to distinguish between the species based on volatile traits and whether individuals exhibit species-specific differences in body odorants. Zebra finches are more social than diamond firetails; nevertheless, both species have an overlapping distribution area. Applying an experimental Y-maze paradigm, we showed that zebra finches can use differences in their species odor fingerprints and displayed a significant preference for the odor of conspecifics over that of heterospecifics, whereas diamond firetails did not reveal a preference. Using gas chromatography and mass spectrometry, we demonstrated that body odorants of the two species were significantly different in relative composition. This finding demonstrates the potential importance of olfactory cues in species recognition, at least in social bird species. Even these two closely related species displayed remarkable differences in their responsiveness to similar chemical cues, which might be caused by species-specific differences in ecology, physiology, or evolution. 相似文献
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Doris Preininger Markus Boeckle Anita Freudmann Iris Starnberger Marc Sztatecsny Walter Hödl 《Behavioral ecology and sociobiology》2013,67(9):1449-1456
Many animals use multimodal (both visual and acoustic) components in courtship signals. The acoustic communication of anuran amphibians can be masked by the presence of environmental background noise, and multimodal displays may enhance receiver detection in complex acoustic environments. In the present study, we measured sound pressure levels of concurrently calling males of the Small Torrent Frog (Micrixalus saxicola) and used acoustic playbacks and an inflatable balloon mimicking a vocal sac to investigate male responses to controlled unimodal (acoustic) and multimodal (acoustic and visual) dynamic stimuli in the frogs’ natural habitat. Our results suggest that abiotic noise of the stream does not constrain signal detection, but males are faced with acoustic interference and masking from conspecific chorus noise. Multimodal stimuli elicited greater response from males and triggered significantly more visual signal responses than unimodal stimuli. We suggest that the vocal sac acts as a visual cue and improves detection and discrimination of acoustic signals by making them more salient to receivers amidst complex biotic background noise. 相似文献
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SUMMARY Sustainable development is a global challenge to science and society. In politics and economics the concepts for establishing a sustainable society are numerous, nonetheless necessary interdisciplinary approaches are still marginalised. Trying to foster a deeper communication between biology and social science, an evolutionary perspective on sustainable development is offered. Subsequently, the role of variability and diversity in evolution is highlighted. Hereby, special attention is devoted, among other things, to the links between variability and stability in the long term. Next, selection and variability are emphasised in the cultural context. This is followed by general implications for sustainability. In contrast to strategies aiming at short-term optimisation and economic efficiency, we argue that the conditions and circumstances maintaining variability and momentary sub-optimal alternatives are highly relevant for a socio-economic system that is heading for sustainable development. 相似文献
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Julia Wohlers-Z?llner Antje Biermann Anja Engel Petra D?rge Aleksandra M. Lewandowska Markus von Scheibner Ulf Riebesell 《Marine Biology》2012,159(11):2503-2518
A comparative analysis of data, obtained during four indoor-mesocosm experiments with natural spring plankton communities from the Baltic Sea, was conducted to investigate whether biogeochemical cycling is affected by an increase in water temperature of up to 6?°C above present-day conditions. In all experiments, warming stimulated in particular heterotrophic bacterial processes and had an accelerating effect on the temporal development of phytoplankton blooms. This was also mirrored in the build-up and partitioning of organic matter between particulate and dissolved phases. Thus, warming increased both the magnitude and rate of dissolved organic carbon (DOC) build-up, whereas the accumulation of particulate organic carbon (POC) and phosphorus (POP) decreased with rising temperature. In concert, the observed temperature-mediated changes in biogeochemical components suggest strong shifts in the functioning of marine pelagic food webs and the ocean’s biological carbon pump, hence providing potential feedback mechanisms to Earth’s climate system. 相似文献
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Susanne Foitzik Ilka Maria Kureck Markus Hannes Rüger Dirk Metzler 《Behavioral ecology and sociobiology》2010,64(10):1641-1654
The ant Hypoponera opacior exhibits alternative reproductive morphs of males and females associated with distinct sexual behaviours. Our long-term study
reports strong seasonality in sexual production with a mating season in early and one in late summer. Winged (alate) reproductives
emerge in June, swarm during the monsoon season and establish new colonies independently. In contrast, wingless worker-like
(ergatoid) reproductives that appear in late August mate within their natal or adjacent nests and either do not disperse or
establish new nests close by. These divergent dispersal patterns allowed us to analyse the impact of local factors on investment
strategies by comparing sex allocation between and within the two reproductive events. The optimal sex ratio for ergatoid
reproductives should be influenced both by competition for matings between brothers (local mate competition) and rivalry among
young locally dispersing queens for workers, nest sites or food (local resource competition). The greater importance of local
resource competition was demonstrated both by a male-biased sex ratio for wingless sexuals and a stronger increase in the
number of males with total sexual production than for the number of queens. Microsatellite analysis revealed that inter-nest
variation in relatedness asymmetry cannot explain split sex ratios in the August generation. Instead, nests with related ergatoid
males raised a male-biased sex ratio contrary to the expectations under local mate competition. In conclusion, male bias in
wingless H. opacior indicates that local mate competition is less strong than local resource competition among ergatoid queens over the help
of workers during nest foundation. 相似文献