Histone Biology and Chemistry     

Bonner J  Ts'o PO 《Science (New York, N.Y.)》1963,141(3581):651-654

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The influence of plant litter diversity on decomposer abundance and diversity     

David A. Wardle  Gregor W. Yeates  Karen I. Bonner 《Soil biology & biochemistry》2006,38(5):1052-1062

Although there has been much recent interest in the effect of litter mixing on decomposition processes, much remains unknown about how litter mixing and diversity affects the abundance and diversity of decomposer organisms. We conducted a litter mixing experiment using litterbags in a New Zealand rainforest, in which treatments consisted of litter monocultures of each of 8 forest canopy and understory plant species, as well as mixtures of 2, 4 and 8 species. We found litter mixing to have little effect on net decomposition rates after either 279 or 658 days, and for each species decomposition rates in mixture treatments were the same as in monoculture. Litter species identity had important effects on litter microfauna, mesofauna and macrofauna, with different litter types promoting different subsets of the fauna. Litter mixing had few effects on densities of mesofauna and macrofauna, but did have some important effects on components of the microfauna, notably microbe-feeding and predatory nematodes. At day 279, litter mixing also consistently reduced the ratio of bacterial-feeding to microbe-feeding (bacterial-feeding+fungal-feeding) nematodes, pointing to mixing causing a significant switch from the bacterial-based to the fungal-based energy channel. Litter mixing sometimes influenced the community composition and diversity of nematodes and macrofauna, but effects of litter mixing on diversity were not necessarily positive, and were much weaker than effects of litter species identity on diversity. We conclude that litter mixing effects on the abundance and diversity of decomposer biota, when they occur, are likely to be of secondary and generally minor significance when compared to the effects of litter species identity and composition.  相似文献   

Treatment of Animal Toxicoses: A Regulatory Perspective     

Susan J. Bright DVM  Michael J. Murphy DVM  JD  PhD  Janice C. Steinschneider MA  JD  Randall A. Lovell DVM  PhD  Lynn O. Post DVM  PhD  CAPT  USPHS 《Veterinary Clinics of North America: Food Animal Practice》2011,27(2):481-512

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Investigation of a permethrin-induced antifeedant effect in Drosophila melanogaster: An ethological approach     

Karen F. Armstrong  Adrian B. Bonner 《Pest management science》1985,16(6):641-650

A permethrin-induced antifeedant effect was demonstrated in Drosophila melanogaster topically treated with a dose of 1.25 ng per fly (LD₅₀ and LD₁₀ were 18.5 and 7.4 ng of permethrin per fly, respectively). The reduction in food consumption in treated flies was due to a decrease in the frequency of feeding and not to the duration of individual meals. These results suggested that the sublethal effect occurred before the process of ingestion. Furthermore, a time-sampling study of individual flies, 30 min after treatment, revealed that the relative frequency of the components of general behaviour were altered. Specifically, locomotory behaviour and inactivity were significantly decreased in contrast to preening, which increased. Continuous observation for 30 min revealed that whilst the length of preening bouts was unaltered, their frequency of occurrence was significantly increased in permethrin-treated flies. The length of bouts of locomotory activity was significantly reduced in treated individuals, but the frequency was increased. The length of rest periods was reduced in treated flies, but no influence of the insecticide could be detected on their bout frequency. Sequential analysis of the transition frequencies of the behavioural components suggested that an underlying disorganisation of general behaviour resulted from the insecticide treatment. Further analysis, of the behaviour of those flies that had fed, indicated that the probability of tasting leading to feeding was decreased by permethrin. The increase in preening behaviour was thought to cause the reduction in locomotor activity, that ultimately resulted in the reduction in feeding. This is discussed in relation to the physiological basis of pyrethroid action and a subsequent irritation response to low doses.  相似文献   

Equine neural angiostrongylosis     

JD WRIGHT  WR KELLY†  J. HAMILTON  AH WADELL† 《Australian veterinary journal》1991,68(2):58-60

Verminous encephalomyelitis due to Angiostrongylus cantonensis larvae was diagnosed in 2 foals at necropsy. The principal clinical feature was tetraparesis, although history and neurological examination revealed progressive and multifocal neurological disease. At presentation, a tentative diagnosis of parasitic larval migration involving the central nervous system (CNS), presumably due to Strongylus vulgaris, was proposed. Dissection of the spinal cord in one case resulted in recovery of intact larvae of both sexes of A. cantonensis. In both foals, histopathology of the brain and spinal cord revealed nematode sections which were consistent with A. cantonensis larvae.  相似文献   

Fish Pathology     

JD Humphrey 《Australian veterinary journal》2002,80(6):370-370

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Furazolidone toxicity in dairy calves     

JD TAYLOR  JA GIBSON  CEF YEATES 《Australian veterinary journal》1991,68(5):182-183

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Cardiomyopathy and woolly haircoat syndrome of Hereford cattle     

GJ STORIE  JA GIBSON  JD TAYLOR 《Australian veterinary journal》1991,68(3):119-119

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Chromosomal RNA: its properties     

D S Holmes  J E Mayfield  G Sander  J Bonner 《Science (New York, N.Y.)》1972,177(43):72-74

We describe the properties of a special class of RNA associated with chromatin. We discuss why this RNA should be considered a distinct class of RNA and not an artifactual degradation product of either transfer or ribosomal RNA.  相似文献   

STRUCTURE AND SYNTHESIS OF A PLANT WOUND HORMONE     

English J  Bonner J  Haagen-Smit AJ 《Science (New York, N.Y.)》1939,90(2336):329-330

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