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排序方式: 共有803条查询结果,搜索用时 46 毫秒
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Denise Risch Nicholas J. Gales Jason Gedamke Lars Kindermann Douglas P. Nowacek Andrew J. Read Ursula Siebert Ilse C. Van Opzeeland Sofie M. Van Parijs Ari S. Friedlaender 《Biology letters》2014,10(4)
For decades, the bio-duck sound has been recorded in the Southern Ocean, but the animal producing it has remained a mystery. Heard mainly during austral winter in the Southern Ocean, this ubiquitous sound has been recorded in Antarctic waters and contemporaneously off the Australian west coast. Here, we present conclusive evidence that the bio-duck sound is produced by Antarctic minke whales (Balaenoptera bonaerensis). We analysed data from multi-sensor acoustic recording tags that included intense bio-duck sounds as well as singular downsweeps that have previously been attributed to this species. This finding allows the interpretation of a wealth of long-term acoustic recordings for this previously acoustically concealed species, which will improve our understanding of the distribution, abundance and behaviour of Antarctic minke whales. This is critical information for a species that inhabits a difficult to access sea-ice environment that is changing rapidly in some regions and has been the subject of contentious lethal sampling efforts and ongoing international legal action. 相似文献
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Ilse Schwinck 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1953,35(3):167-174
Zusammenfassung Der Weibchenduftstoff von Plodia interpunctella Hb. ist, entgegen den Angaben Barths, auch bei Zimmertemperatur sehr stabil; geringe Mengen (von 2 in 4 min abgegebener Duftstoff) konnten nach über 2 Tagen in einer geschlossenen Schale durch den Schwirrtanz der Männchen noch nachgewiesen werden.Zur Frage der Artspezifität der Sexualduftstoffe zeigten Versuche in geschlossenen Schalen, im freien Flugkäfig und in luftdurchströmten Apparaturen für die beiden nahe verwandten Gattungen Plodia interpunctella Hb. und Ephestia kühniella Z. keine Spezifität des Erregungs und Anlockungsvorganges, zu einer Kopulation zwischen gattungsfremden Tieren kam es aber trotz wilder Kopulationsversuche nicht. 相似文献
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Peter L Hagedoorn Martijn C.P.F Driessen Marieke van den Bosch Ilse Landa Wilfred R Hagen 《FEBS letters》1998,440(3):6683
The redox chemistry of Pyrococcus furiosus rubredoxin and ferredoxin has been studied as a function of temperature in direct voltammetry and in EPR monitored bulk titrations. The Ems of both proteins, measured with direct voltammetry, have a normal (linear) temperature dependence and show no pH dependence. EPR monitoring is not a reliable method to determine the temperature dependence of the Em: upon rapid freezing the proteins take their conformation corresponding to the freezing point of the solution. 相似文献
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Cornelia Speth Jörg T. Epplen Ilse Oberbäumer 《In vitro cellular & developmental biology. Animal》1991,27(8):646-650
Summary Oligonucleotide fingerprinting was applied to investigate the relatedness of several cell lines that were established between
1973 and 1977 from a teratocarcinoma. We were able to distinguish cell lines derived at different times. In addition, sublines
from one cell line (PYS-2) could be discriminated by using a combination of different probes. Therefore multilocus fingerprinting
with oligonucleotides is a useful method for monitoring changes in cell lines kept in culture for many generations.
This work was supported by the Deutsche Forschungsgemeinschaft (OB 66/2-1) and by the VW-Stiftung. 相似文献
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In the spore germination test the germination rate of ALTERNARIA TENUIS Neerg on serum-agar with serum from rats exposed to 3,450 m altitude was significently higher than with serum from rats at ground level. The responsible factor has not yet been identified. 相似文献
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Bruno Hoste Lieve Luyten Ilse Claeys Elke Clynen Mazibur M. Rahman Arnold De Loof Michael Breuer 《Entomologia Experimentalis et Applicata》2002,104(2-3):281-288
In order to unravel the physiological, endocrine, and behavioral differences between gregarious and solitarious forms of the desert locust, Schistocerca gregaria (Forsk.) (Orthoptera, Acrididae), a constant supply of rather large numbers of solitary individuals has to be guaranteed. This represents a bottleneck, mainly because of the intensity of the labor involved and limited laboratory accommodation. The method we describe here substantially reduces the space and manpower needed. The survival rate we obtained in the solitarised population was relatively high, reaching about 55%. The optimal rearing temperature proved to be 32–36 °C. Cabbage leaves and oat flakes sufficed for feeding all year round. Special racks have been designed that enable high density stacking and easy handling. The solitarisation process was monitored over ten consecutive generations. Changes in morphometrics, eye stripes, color, and behavior were recorded, of which only morphometrics, temperature related development, and mortality are discussed. A shift towards the solitarious phase was recorded, with clear differences between gregarious, 1st generation and 7th to 10th generation solitarious locusts. 相似文献