Denoising source separation is a recently introduced framework for building source separation algorithms around denoising procedures. Two developments are reported here. First, a new scheme for accelerating and stabilising convergence by controlling step sizes is introduced. Second, a novel signal-variance based denoising function is proposed. Estimates of variances of different source are whit...

Kinetic measurements in the pH range 7.0 to 9.4 were made by the temperature jump technique, and comparative values of Keg were determined by a spectrophotometric titration method based on absorption difference at 550 rnp between ferriand ferrocytochrome C. Also, stopped flow experiments at 550 rnp were performed at pH 9.5. In all of these experiments, excess sodium ferrocyanide (8 X 10u3 M) wa...

Coastal acid sulfate soils (CASS) constitute a serious and global environmental problem. Oxidation of iron sulfide minerals exposed to air generates sulfuric acid with consequently negative impacts on coastal and estuarine ecosystems. Tidal inundation represents one current treatment strategy for CASS, with the aim of neutralizing acidity by triggering microbial iron- and sulfate-reduction and ...

The electronic structures, formation energies, and band edge positions of anatase TiO2 doped with transition metals have been analyzed by ab initio band calculations based on the density functional theory with the planewave ultrasoft pseudopotential method. The model structures of transition metal-doped TiO2 were constructed by using the 24-atom 2 × 1 × 1 supercell of anatase TiO2 with one Ti a...

The biologically and nanotechnologically important heme protein cytochrome b(562) was reconstructed with zinc and copper porphyrins, leading to significant changes in the spectral, redox and electron transfer properties. The Cu form shifts the redox potential by +300 mV and exhibits high electron transfer, while the Zn form is redox inert.

The soil solid-liquid distribution coefficient (Kd) value is of great significance in understanding and modelling the environmental behaviour of soil contaminants. For many years, the batch sorption technique has been used for the determination of such values. Here, we propose an alternative 'mini-column' approach in which somewhat more realistic soil conditions are maintained. In particular, t...

A novel cellular response to oxidative stress has been discovered, in which the activity of a molecular chaperone, Hsp33, is modulated by the environmental redox potential. This provides a rapid first defence mechanism against the potentially very harmful toxic effects of oxidative stress.

An Au(25) cluster protected by azobenzene derivative thiolates (S-Az) ([Au(25)(S-Az)(18)](-)) was synthesized with the aim of producing a photoresponsive Au(25) cluster. The matrix-assisted laser desorption/ionization mass spectrum of the product revealed that [Au(25)(S-Az)(18)](-) was synthesized in high purity. Optical absorption spectra of [Au(25)(S-Az)(18)](-) obtained before and after phot...

This study investigated the effects of reed and willow on bioremediation of landfill leachate in comparison with an unplanted control by measuring redox potential levels in the rhizosphere of microcosm systems in a greenhouse. Plants had a significant influence on redox potential relative to the plant-less system. Redox potential in the reed rhizosphere was anoxic (mean -102±85 mV), but it was ...

Soil redox potential (Eh), concentrations of oxygen (O2) and three greenhouse gases (CO2, CH4, and N2O) were measured in the soil profile of a coastal forest at ridge, transition, and swamp across a hydrological gradient. The results delineated a distinct boundary in soil Eh and O2 concentration between the ridge and swamp with essentially no overlap between the two locations. Critical soil Eh ...