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161.
K. G. Davey 《Journal of nematology》1995,27(4):433-440
While nematodes are sometimes regarded as osmoconformers, at least one species is capable of short-term osmoregulation over a wide range of osmotic environments, and the principal site of osmoregulation is the body wall. This general osmoregulation is important to the life of the nematode not only in confronting variations in the environment, but also in maintaining its hydrostatic skeleton. There is also evidence suggesting that compartments exist in some nematodes and that water exchange between the compartments is limited and slow. The ability to regulate the internal movements of water is important in molting and in the infective process. Hormones may be the mediators of osmotic control. 相似文献
162.
A predictive model for combined temperature and water activity on microbial growth during the growth phase 总被引:18,自引:0,他引:18
K R Davey 《The Journal of applied bacteriology》1989,67(5):483-488
An empirical and generalized model is presented, based on a modified Arrhenius equation, for predicting the combined effect of temperature and water activity on the growth rate of bacteria. When it was applied to seven separate sets of wide ranging published results, spanning some 50 years and including a spore-former and a silage micro-organism, predictions explained between 92.9 and 99.0% of the variation in the results with an overall mean of 96.6%. Advantages over existing models are that it is relatively easy to fit to data using least squares regression and requires only five coefficients. These, together with its simplicity and demonstrated wide application, will facilitate its practical use. 相似文献
163.
Cytochromes of two methane-utilizing bacteria 总被引:5,自引:0,他引:5
164.
165.
Snakes and ladders: legal coercion,housing precarity,and home-making aspirations in southern England
Ryan Davey 《The journal of the Royal Anthropological Institute》2020,26(1):12-29
The potential for eviction is an ordinary condition of domestic life for many in Europe and North America. This poses a challenge to anthropological theories of the state's presence in ordinary homes, which have accounted for public housing and mass displacement, but not liberalized settings where the state has ostensibly withdrawn from the home. Studies of housing precarity identify state policy and capitalist transformation among its sources, but the consequences of housing precarity for domesticity itself have not been fully explored. Private renters on a housing estate in southern England responded to the bleak prospect of eviction with home-making pursuits that would instil a sense of optimism in their homes, including mortgage-based ownership and immersive home entertainment technology. By examining the interplay between fears of eviction and home-making aspirations, this article argues that the British state's organization of legitimate coercion has a subtle but significant influence on tenants’ ethical visions of what constitutes a good home. 相似文献
166.
167.
168.
S Davey M L Nass J V Ferrer K Sidik A Eisenberger D L Mitchell G A Freyer 《Nucleic acids research》1997,25(5):1002-1008
In addition to nucleotide excision repair (NER), the fission yeast Schizosaccharomyces pombe possesses a UV damage endonuclease (UVDE) for the excision of cyclobutane pyrimidine dimers and 6-4 pyrimidine pyrimidones. We have previously described UVDE as part of an alternative excision repair pathway, UVDR, for UV damage repair. The existence of two excision repair processes has long been postulated to exist in S.pombe, as NER-deficient mutants are still proficient in the excision of UV photoproducts. UVDE recognizes the phosphodiester bond immediately 5'of the UV photoproducts as the initiating event in this process. We show here that UVDE activity is inducible at both the level of uve1+ mRNA and UVDE enzyme activity. Further, we show that UVDE activity is regulated by the product of the rad12 gene. 相似文献
169.
M. H. Bhatti T. Percival C. D. M. Davey G. G. Henshaw D. Blakesley 《Plant cell reports》1997,16(11):802-806
Embryogenic tissue of nine sweet potato [Ipomoea batatas (L.) Lam] genotypes from Asia, Africa and the Americas was established from in vitro axillary buds on Murashige and Skoog
medium supplemented with 2,4-dichlorophenoxyacetic acid or 2,4,5-trichlorophenoxyacetic acid. Embryogenic aggregates, 1.0–2.0
mm in diameter, were encapsulated in alginate gel, precultured on medium containing elevated levels of sucrose and dehydrated
prior to rapid freezing in liquid nitrogen. The maximum survival of embryogenic tissue ranged from 4% to 38%, depending on
the genotype. With the incorporation of a slow-cooling step, survival was generally much higher than that obtained after rapid
freezing alone. Five of eight genotypes tested with this protocol gave survival percentages in excess of 55%, and a further
two in excess of 33%, all after evaporative dehydration. The most effective sucrose treatment(s), however, varied with the
genotype.
Received: 7 October 1996 / Revision received: 16 December 1996 / Accepted 27 January 1997 相似文献
170.
A flux analysis of glucose metabolism in the filamentous fungus Rhizopus oryzae was achieved using a specific radioactivity curve-matching program, TFLUX. Glycolytic and tricarboxylic acid cycle intermediates labeled through the addition of extracellular [U-14C]glucose were isolated and purified for specific radioactivity determinations. This information, together with pool sizes and the rates of glucose utilization and end product production, provided input for flux maps of the metabolic network under two different experimental conditions. Based upon the flux analysis of this system, a mutant of R. oryzae with higher lactate and lower ethanol yields than the parent was sought for and found. 相似文献