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71.
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Growth characteristics of a thermotolerant methylotrophic Bacillus sp. (NCIB 12522) in batch culture
Nader Al-Awadhi Thomas Egli Geoffrey Hamer 《Applied microbiology and biotechnology》1988,29(5):485-493
Summary This contribution deals with problems associated with the culture of a thermotolerant methylotrophic Bacillus sp. The results reported clearly demonstrate why conventional enrichment/isolation procedures have, in the past, failed to allow such microbes to assert themselves. The catastrophic effect of carbon substrate (methanol) exhaustion on such cultures is clearly evidenced, but the effects of other nutrient exhaustion or limitations are demonstrated to be markedly less stringent. The failure of such cultures to complete the sporulation process when growing on methanol has important consequences with respect to their survival characteristics. 相似文献
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The presence or absence of light during flotation restricted environmental stimulation: Effects on plasma cortisol,blood pressure,and mood 总被引:1,自引:0,他引:1
John W. Turner Jr. Thomas Fine Gina Ewy Peter Sershon Thomas Freundlich 《Applied psychophysiology and biofeedback》1989,14(4):291-300
This study examined the effect of light on relaxation associated with flotation restricted environmental stimulation therapy (REST), as measured by plasma cortisol, mean arterial pressure, and psychometric parameters. Twenty-one subjects were paired by baseline cortisol levels into two groups: one experiencing flotation REST in the presence of light (REST-L) and one experiencing flotation REST in the absence of light (REST-D). Subjects were 15 male and 6 female students aged 22–28 in normal health who had not experienced REST. Repeated flotation REST (8 sessions) either with light or without light was associated with a decrease in plasma cortisol and a decrease in mean arterial pressure, with no differences in effectiveness between groups. The psychometric assessment of mood, using the POMS scale, before and after sessions 1 and 8 revealed mood state improvement in both REST-L and REST-D groups. These data suggest that the presence of light did not compromise the flotation REST experience, as evidenced by the lack of difference between REST-L and REST-D groups. 相似文献
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Breeding site characteristics have been studied for the three species of newt that occur in Britain, the Palmate ( Triturus helveticus (Razoumowski)), Smooth ( T. vulgaris (L.)) and Warty ( T. cristatus (Laurenti)). The Warty newt was seldom found in the absence of the much commoner Smooth newt, but seemed to prefer sites that were relatively large and deep and that had a high proportion of open water surface. All three species tended to breed in ponds having abundant aquatic vegetation. Smooth newts, unlike Palmate newts, were rarely encountered in water with pH <6. The Smooth newt tended to be found in water with relatively high concentrations of metals, while the reverse was true for the Palmate newt. Over Britain, Smooth and Warty newts are relatively less common in soft water areas, while the Palmate is less common in hard water areas. Possible reasons for these associations are discussed. 相似文献
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W. Thelwall Thomas 《BMJ (Clinical research ed.)》1899,1(2005):1329-1330
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