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711.
W. E. Scott M. T. Seaman A. D. Connell S. I. Kohlmeyer D. F. Toerien 《African Journal of Aquatic Science》2013,38(2):43-58
SUMMARY Hartbeespoort Dam is a eutrophic, warm monomictic lake with overturn occurring in April. The lake is stratified for about six months of the year and in late summer the stratification appears stable. Light penetration in the dam depends both on the inflow of turbid water as well as on the magnitude of the algal population. In summer the surface waters are often super-saturated with oxygen, whilst the hype limnion is anaerobic. The concentrations of nitrogen compounds, phosphate, Na, K, Ca, CI and SO4 are higher in waters entering the dam via the Crocodile River. Nitrogen compounds arc the primary growth-limiting nutrients for algal growth and phosphate is the secondary growth-limiting nutrient. Phosphate concentrations in the water have increased approximately a hundredfold since 1928 and NO3 ?N concentrations about threefold. The pH as well as the mineral content of the dam have also increased over the last 50 years. 相似文献
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Methods were developed for the formation of protoplasts and spheroplasts of gastrointestinal strains of Lactobacillus reuteri, Lactobacillus gasseri, and Lactobacillus salivarius. Attempts to regenerate vegetative cells from protoplasts were not successful, but spheroplasts could be regenerated consistently for five of six strains. 相似文献
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In the wake of recent national and global events, biological weapons have become an increasingly urgent issue. Preparedness and defense are now the topic of numerous conferences and funding opportunities. Due to this increasing activity researchers must now focus more intently on their own safety and security. Bio-safety measures are analyzed by means of risk assessments. In this paper we will explore qualitative risk assessments and the risks associated with six specific pathogens and toxins that are potential bio-terrorism agents: Bacillus anthracis, Yersinia pestis, Francisella tularemia, Smallpox virus, and the two toxins, ricin and botulinum. 相似文献
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Anne Clancy Claire Heride Adn Pinto-Fernndez Hannah Elcocks Andreas Kallinos Katherine J. Kayser-Bricker Weiping Wang Victoria Smith Simon Davis Shawn Fessler Crystal McKinnon Marie Katz Tim Hammonds Neil P. Jones Jonathan OConnell Bruce Follows Steven Mischke Justin A. Caravella Stephanos Ioannidis Christopher Dinsmore Sunkyu Kim Axel Behrens David Komander Benedikt M. Kessler Sylvie Urb Michael J. Clague 《The Journal of cell biology》2021,220(3)
When a ribosome stalls during translation, it runs the risk of collision with a trailing ribosome. Such an encounter leads to the formation of a stable di-ribosome complex, which needs to be resolved by a dedicated machinery. The initial stalling and the subsequent resolution of di-ribosomal complexes requires activity of Makorin and ZNF598 ubiquitin E3 ligases, respectively, through ubiquitylation of the eS10 and uS10 subunits of the ribosome. We have developed a specific small-molecule inhibitor of the deubiquitylase USP9X. Proteomics analysis, following inhibitor treatment of HCT116 cells, confirms previous reports linking USP9X with centrosome-associated protein stability but also reveals a loss of Makorin 2 and ZNF598. We show that USP9X interacts with both these ubiquitin E3 ligases, regulating their abundance through the control of protein stability. In the absence of USP9X or following chemical inhibition of its catalytic activity, levels of Makorins and ZNF598 are diminished, and the ribosomal quality control pathway is impaired. 相似文献