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The revision of the antarctic–subantarctic species Orchomenopsis reducta Schellenberg, 1931, has led to its attribution to a new, highly apomorphic genus: Falklandia gen.n. A new definition of the uristid group is given and Falklandia with 36 other lysianassoid genera are attributed to this supposedly monophyletic group. 相似文献
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Cyanide-Resistant Root Respiration and Tap Root Formation in Two Subspecies of Hypochaeris radicata 总被引:1,自引:0,他引:1
Root respiration of the tap root forming species Hypochaeris radicata L. was measured during tap root formation. A comparison was made of two subspecies: H. radicata L. ssp. radicata L., a subspecies from relatively rich soils, and H. radicata L. ssp. ericetorum Van Soest, a subspecies from poor acidic soils. Root respiration was high and to a large extent inhibited by hydroxamic acid (SHAM) before the start of the tap root formation, indicating a high activity of an alternative non-phosphorylative electron transport chain. The rate of root respiration was much lower and less sensitive to SHAM when a considerable tap root was present. However, root respiration was also cyanide-resistant when a tap root was present, indicating that the alternative pathway was still present. A decreased rate of root respiration coincided with an increase of the content of storage carbohydrates, mainly in the tap root. The level of reducing sugars was constant throughout the experimental period, and it was concluded that the activity of the alternative oxidative pathway was significant in oxidation of sugars that could not be utilized for purposes like energy production, the formation of intermediates for growth or for storage. Root respiration decreased after the formation of a tap root. This decrease could neither be attributed to a gradual disappearance of the alternative chain, nor to a decreased level of reducing sugars. No differences in respiratory metabolism between the two subspecies have been observed, suggesting that a high activity of the alternative oxidative pathway is not significant in adaptation of the present two subspecies to relatively nutrient-rich or poor soils. 相似文献
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RAYMOND IGNAR DONALD ENGLISH LUIS JIMENEZ 《Journal of Rapid Methods and Automation in Microbiology》1998,6(1):51-58
Abstract The Celsis ATP Bioluminescence method was optimized and validated to detect the presence of microbial contamination in High Fluoride and Triclosan dentifrice formulations. Several enrichment broths were evaluated by using a 24–27 h incubation period. The ATP concentrations of the enrichment broths were found to a range from 0.012 to 0.040 nM. None of the tested enrichment broths were found to exhibit any sample inhibition/enhancement effects on the ATP Bioluminescence reaction. Dentifrice suspensions were inoculated with bacteria, yeast, and mold. All test microorganisms (ca. 1–15 CFU/g) were detected within a 24–27 h incubation period by using TAT Broth Base enrichment broths containing different concentrations of the following ingredients: Tween 20, Neopeptone, Dextrose, Triton X-100, Thiosulfate, Sodium Dibasic Phosphate, and Glycine. Negative ATP response after 24–27 h of incubation at 35C indicates the absence of contamination from these products. 相似文献
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