To follow and model evolution of a microbial population in the chemostat, parameters are needed that give an indication of the absolute extent of evolution at a high resolution of time. In this study the evolution of the maximum specific growth rate ( micro (max)) and the residual glucose concentration was followed for populations of Escherichia coli K-12 under glucose-limited conditions at dil...

A streptomycin-resistant variant of Xanthomonas campestris was grown in defined nutrient-deficient media in both batch and continuous culture. The production, composition and viscosity of the extracellular polysaccharide (xanthan) synthesized by this strain were influenced by the fermentation time and nutrient exhaustion in batch culture and by the dilution rate in continuous culture. The speci...

Dolan and McKeon (2005) have recently criticized microzooplankton grazing rate estimates by the dilution approach as being systematically biased and significantly overestimated. Their argument is based on observed mortality responses of ciliated protozoa to reduced food in several coastal experiments and a global extrapolation which assumes that all grazing in all ocean systems scales to the ab...

Continuous ethanol fermentation from cheap sugar cane molasses was studied. Two strains of Saccharomyces cerevisiae were used, one of them flocculent, in order to evaluate the performance of fluidized tubular reactors, with and without support for yeast immobilisation (polyurethane foam and expanded clay argilate granules were tested). In this heterogeneous continuous system, with three phases,...

The first comparative study of DC, RF and VHF excitation for the plasma enhanced chemical vapor deposition (PECVD) of intrinsic layers of hydrogenated amorphous silicon (a-Si:H) is presented. The effects of hydrogen dilution on film stability are emphasized. Growth rates at comparable plasma power are presented for substrate temperatures between 100°C and 300°C and for various H2 dilution ratio...

Load theory of attention proposes that distractor processing is reduced in tasks with high perceptual load that exhaust attentional capacity within task-relevant processing. In contrast, tasks of low perceptual load leave spare capacity that spills over, resulting in the perception of task-irrelevant, potentially distracting stimuli. Tsal and Benoni (2010) find that distractor response competit...

In the present work, the model reference nonlinear controller (MRNC) based on pseudo dynamic model is designed to a continuous bioreactor which exhibits input multiplicities in dilution rate on productivity. i.e., two values of dilution rate will give the same value of productivity. The performance of MRNC and linear PI controller have been evaluated through simulation studies. The optimal para...

The fate of pollutants in the environment is affected by the presence of easily degradable carbon sources. As a step towards understanding these complex interactions, a model system was explored: the degradation of mixtures of glucose (i.e., an easily degradable substrate) and 3-phenylpropionic acid (3ppa) (a model pollutant) by Escherichia coli ML 30 was studied systematically in carbon-limite...