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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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C J Van Noorden W M Frederiks D C Aronson F Marx K Bosch G N Jonges I M Vogels J James 《Virchows Archiv. B, Cell pathology including molecular pathology》1987,52(6):501-511
Extrahepatic cholestasis induced by ligation and transsection of the common bile duct caused a change in the parenchyma/stroma relationship in rat liver. Two weeks after ligation, the periportal zones of the parenchyma were progressively invaded by expanding bile ductules with surrounding connective tissue diverging from the portal areas. Parenchymal disarray developed and small clumps of hepatocytes or isolated hepatocytes were scattered within the expanded portal areas. These cells showed normal activity of lactate, succinate and glutamate dehydrogenase and may, therefore, be considered to be functionally active. After cholestasis the remainder of the liver parenchyma showed adaptational changes with respect to glucose homeostasis, as demonstrated by histochemical means. Glycogen stores disappeared completely whereas glycogen phosphorylase activity increased about ten fold. The increased glycogen phosphorylase activity and glycogen depletion indicate a greater glycogenolytic capacity in liver parenchyma after bile duct ligation to maintain as far as possible a normal plasma glucose concentration. The parenchymal distribution pattern of glucose-6-phosphatase activity did not change significantly after bile duct ligation. The isolated hepatocytes within the expanded portal tracts showed a high activity of this enzyme whereas the pericentral parenchyma was only moderately active. The distribution patterns of glucose-6-phosphate dehydrogenase and lactate dehydrogenase activity in the liver parenchyma were also largely unchanged after bile duct ligation, but the histochemical reaction for glucose-6-phosphate dehydrogenase activity demonstrated infiltration of the remainder of the parenchyma by non-parenchymal cells, possibly Küpffer cells and leucocytes as part of an inflammatory reaction. Under normal conditions the mitochondrial enzymes succinate and glutamate dehydrogenase show an opposite heterogenous distribution pattern in liver parenchyma. Following cholestasis both enzymes became uniformly distributed. The underlying regulatory mechanism for these different changes in distribution patterns of enzyme activities is not yet understood. 相似文献
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Calli of P. argentatum were grown on a newly designed liquid nutrient flow-through system which facilitated the subculturing of calli and delayed
browning for 6 weeks. Friable calli were obtained on half-strength Gamborg B5-medium supplemented with 0.05 mgl−1 2,4-dichlorophenoxyacetic acid. Shoots developed on media supplemented with 0.2 mgl−1 benzylaminopurine but lacking 2,4-dichlorophenocyacetic acid. 相似文献
6.
Normal phenotype and slight mental retardation in de novo distal 8p deletion (8pter----8p23.1:) 总被引:1,自引:0,他引:1
In this report we present a 9-year-old boy with mental retardation, behavioural problems and terminal deletion of the short arm of chromosome 8(8pter----8p23.1:). In contrast with previously reported patients with larger terminal and interstitial 8p deletions he did not present major phenotypic abnormalities. 相似文献
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P.J.L. Derikx H.J.M. Op den Camp A.M. Wagner G. Straatsma L.J.L.D. van Griensven G.D. Vogels 《FEMS microbiology letters》1990,66(1-3):307-311
Abstract The respiratory pathways of Agaricus bisporus and Scytalidium thermophilum were studied. A. bisporus appeared to possess both a cyanide-sensitive and a cyanide-insensitive respiration while in S. thermophilum the cyande-insensitive respiration was absent. Growth experiments showed the ecological advantage for A. bisporus under conditions where cytochrome mediated respiration is inhibited. 相似文献
8.
Jan T. Keltjens Ben W. te Brömmelstroet ServéW.M. Kengen Chris van der Drift Godfried D. Vogels 《FEMS microbiology letters》1990,87(3-4):327-332
Abstract In the process of methanogenesis, 5,6,7,8-tetrahydromethanopterin (H4 MPT) is the carrier of the C1 unit at the formyl through methyl state of reduction. By the transfer of a formyl group from formylmethanofuran, 5-formyl- and 10-formyl-H4 MPT are formed in hydrogenotrophic and methylotrophic organisms, respectively. Cyclohydrolysis of the 5- and 10-formyl derivatives then yields 5,10-methenyl-H4 MPT, which is reduced in two subsequent coenzyme F420 -dependent reactions to 5-methyl-H4 MPT. Following the transfer of the methyl group to coenzyme M, the substrate of the terminal step in methanogenesis, methylcoenzyme M, is produced. In this paper properties of the enzymes catalyzing the individual H4 MPT-dependent reactions are discussed. 相似文献
9.
Nico K. Goosen Anja M. C. Horemans Silvia J. W. Hillebrand Claudius K. Stumm Godfried D. Vogels 《Archives of microbiology》1988,150(2):165-170
The sapropelic ciliate Plagiopyla nasuta was isolated and cultured in monoculture. Optimal conditions for growth were: 15–20°C, pH about 7, and about 2% of oxygen in the headspace. Cultures of P. nasuta produced methane. Epifluorescence microscopy revealed the presence of methanogenic bacteria as endosymbionts. An endosymbiont of the ciliate was isolated and identified as Methanobacterium formicicum. In the ciliate cell these methanogens were found to be closely associated with microbody-like organelles. No mitochondria could be detected. 相似文献
10.
Summary The use of reticulated polyurethane foam as a support material for the immobilization of methanogenic associations and its application to the anaerobic treatment of fine particulate solid wastes was investigated. The colonization of polyurethane support particles in a continuous upflow reactor fed on a mixture of acetate, propionate and butyrate, was both rapid and dense. The combination of rumen microorganisms and colonized support particles in a two-phase digester resulted in an efficient anaerobic decomposition of papermill sludge. 相似文献