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181.
182.
Michael R. Hoffmann Bruce C. Faust Fern A. Panda Hong H. Koo Henry M. Tsuchiya 《Applied microbiology》1981,42(2):259-271
Different strains of Thiobacillus ferrooxidans and Thiobacillus thiooxidans were used to catalyze the oxidative dissolution of iron pyrite, FeS2, in nine different coal samples. Kinetic variables and parametric factors that were determined to have a pronounced effect on the rate and extent of oxidative dissolution at a fixed Po2 were: the bacterial strain, the nitrogen/phosphorus molar ratio, the partial pressure of CO2, the coal source, and the total reactive surface area of FeS2. The overall rate of leaching, which exhibited a first-order dependence on the total surface area of FeS2, was analyzed mathematically in terms of the sum of a biochemical rate, ν1, and a chemical rate, ν2. Results of this study show that bacterial desulfurization (90 to 98%) of coal samples which are relatively high in pyritic sulfur can be achieved within a time-frame of 8 to 12 days when pulp densities are ≤20% and particle sizes are ≤74 μm. The most effective strains of T. ferrooxidans were those that were isolated from natural systems, and T. ferrooxidans ATCC 19859 was the most effective pure strain. The most effective nutrient media contained relatively low phosphate concentrations, with an optimal N/P molar ratio of 90:1. These results suggest that minimal nutrient additions may be required for a commercial desulfurization process. 相似文献
183.
184.
R Raghunathan T M Mundy J Faust S Misra 《Journal of immunology (Baltimore, Md. : 1950)》1985,135(4):2429-2431
Immune deficiency, as defined by significant decreases in lymphocyte Con A and allo-reactivity and in natural killer (NK) function, was induced in normal adult mice by i.p. injections of combinations of allogeneic testicular germ cells and splenic leukocytes over 3 wk. This immune deficiency was evident at 8 wk after initial injection, and profound by 12 wk. Neither leukocytes nor testicular cells, given alone, were able to induce similar immune deficiency. These findings suggest the possibility that allogeneic germ cells and leukocytes of semen, on repeated administration, may induce immune deficiency and may act as co-factors to viral agents in the development of clinical AIDS in humans. 相似文献
185.
186.
Daniel Asarnow Bei Wang Wen-Hsin Lee Yuanyu Hu Ching-Wen Huang Bryan Faust Patricia Miang Lon Ng Eve Zi Xian Ngoh Markus Bohn David Bulkley Andrés Pizzorno Beatrice Ary Hwee Ching Tan Chia Yin Lee Rabiatul Adawiyah Minhat Olivier Terrier Mun Kuen Soh Frannie Jiuyi Teo Cheng-I Wang 《Cell》2021,184(12):3192-3204.e16
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187.
Sacha Ferdinandusse Simone Denis Phyllis L. Faust Ronald J. A. Wanders 《Journal of lipid research》2009,50(11):2139-2147
It is well established that peroxisomes play a crucial role in de novo bile acid synthesis. Studies in patients with a peroxisomal disorder have been indispensable for the elucidation of the precise role of peroxisomes. Several peroxisomal disorders are associated with distinct bile acid abnormalities and each disorder has a characteristic pattern of abnormal bile acids that accumulate, which is often used for diagnostic purposes. The patients have also been important for determining the pathophysiological consequences of defects in bile acid biosynthesis. In this review, we will discuss all the peroxisomal steps involved in bile acid synthesis and the bile acid abnormalities in patients with peroxisomal disorders. We will show the results of bile acid measurements in several tissues from patients, including brain, and we will discuss the toxicity and the pathological effects of the abnormal bile acids. 相似文献
188.
Feeding strategies enhance high cell density cultivation and protein expression in milliliter scale bioreactors
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Georg Faust Nils H. Janzen Christoph Bendig Lin Römer Klaus Kaufmann Dirk Weuster‐Botz 《Biotechnology journal》2014,9(10):1293-1303
Miniature bioreactors under parallel fed‐batch operations are not only useful screening tools for bioprocess development but also provide a suitable basis for eventual scale‐up. In this study, three feeding strategies were investigated: besides the established intermittent feeding by a liquid handler, an optimized microfluidic device and a new enzymatic release system were applied for parallel fed‐batch cultivation of Escherichia coli HMS174(DE3) and BL21(DE3) strains in stirred‐tank bioreactors on a 10 mL scale. Lower fluctuation in dissolved oxygen (DO) and higher optical densities were measured in fed‐batch processes applying the microfluidic device or the enzymatic glucose/fructose release system (conversion of intermittently added sucrose by an invertase), but no difference in dry cell weights (DCW) were observed. With all three feeding strategies high cell densities were realized on a milliliter scale with final optical density measured at 600 nm (OD600) of 114–133 and final DCW concentrations of 69–70 g L–1. The effect of feeding strategies on the expression of two heterologous proteins was investigated. Whereas no impact was observed on the expression of the spider silk protein eADF4(C16), the fluorescence of enhanced green fluorescence protein (eGFP) was reproducibly lower, if an intermittent glucose feed was applied. Thus, the impact of feeding strategy on expression is strongly dependent on the E. coli strain and/or expressed protein. As a completely continuous feed supply is difficult to realize in miniature bioreactors, the enzymatic release approach from this study can be easily applied in all microfluidic system to reduce fluctuations of glucose supply and DO concentrations. 相似文献
189.
Classic bladder exstrophy: Frequent 22q11.21 duplications and definition of a 414 kb phenocritical region
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Markus Draaken Friederike Baudisch Bernd Timmermann Heiner Kuhl Martin Kerick Judith Proske Lars Wittler Tracie Pennimpede Anne‐Karoline Ebert Wolfgang Rösch Raimund Stein Enrika Bartels Catharina von Lowtzow Thomas M. Boemers Stefan Herms John P. Gearhart Yegappan Lakshmanan Christina Clementsson Kockum Gundela Holmdahl Göran Läckgren Agnetha Nordenskjöld Simeon A. Boyadjiev Bernhard G. Herrmann Markus M. Nöthen Michael Ludwig Heiko Reutter 《Birth defects research. Part A, Clinical and molecular teratology》2014,100(6):512-517
190.
Tim Drissen Christopher Faust Robin Stadtmann Julia T. Treitler Stefan Zerbe Jasmin Mantilla-Contreras 《Plant biosystems》2013,147(6):756-766
AbstractIslands crucially contribute to the Mediterranean Basin’s high floristic diversity, which, however, is at risk facing climate and land-use changes. Besides the identification of highly diverse areas, the knowledge about factors favouring diversity is of great importance. We analysed plant species diversity and composition related to environmental factors over varied vegetation units on a former Italian prison island in the northwest of Sardinia. Due to a long history of land use with grazing and later abandonment the nowadays protected island features a semi-natural landscape and can serve as an example for strongly anthropogenic altered insular ecosystems. Floristic composition, soil properties, microclimate and ungulate abundance were assessed. Relationships of vegetation composition and diversity with abiotic variables were examined by Canonical Correspondence Analysis, which indicated the importance of air temperature, soil moisture, slope gradient and C/N ratio for floristic differentiation. Most important abiotic factors for plant species richness were relative air humidity and soil moisture, while floristic diversity was mainly determined by air temperature and pH. Furthermore, observation data pointed to an adverse influence of ungulate abundance for plant species diversity. Regarding nature conservation, grazing intensity thus must be critically taken into account, especially for sensitive vegetation units like the coastal garrigue. 相似文献