Cell-density-dependent sensitivity of a mer-lux bioassay

Cell-density-dependent sensitivity of a mer-lux bioassay.

The sensitivity of a previously described assay (O. Selifonova, R. Burlage, and T. Barkay, Appl. Environ. Microbiol. 59:3083-3090, 1993) for the detection of bioavailable inorganic mercury (Hg2+) by the activation of a mer-lux fusion was increased from nanomolar to picomolar concentrations by reducing biomass in the assays from 10(7) to 10(5) cells ml-1. The increase in sensitivity was due to a...

Cell density dependent acid sensitivity in stationary phase cultures of enterohemorrhagic Escherichia coli O157:H7.

Escherichia coli O157:H7, the causative agent of hemorrhagic colitis and hemolytic uremic syndrome, can survive in a highly acidic environment. The acid resistance of this organism, as measured by its ability to survive in low pH, depended on the density of the cells present during the assay. At low cell densities (</=2 x 10(7) ml(-1)), about 100% of the stationary phase cells survived in Luria...

Wavelet Based Estimation of the Derivatives of a Density for m-Dependent Random Variables

Here, we propose a method of estimation of the derivatives of probability density based wavelets methods for a sequence of m−dependent random variables with a common one-dimensional probability density function and obtain an upper bound on Lp-losses for the such estimators.

Construction and Characterization of a Lux-Marked Phenanthrene Degrading Bacterium

A New Sensitivity Study of Thermal Stress Distribution for a Planar Solid Oxide Fuel Cell

Converting chemical energy into electricity is done by an electro-chemical device known as a fuel cell. Thermal stress is caused at high operating temperature between 700 oC to 1000 oC of SOFC. Thermal stress causes gas escape, structure variability, crack initiation, crack propagation, and cease operation of the SOFC before its lifetime. The aim of this study is to presen...