Ligand dissociation mediated charge transfer observed at colloidal W18O49 nanoparticle interfaces.

Understanding charge transfer dynamics through the ligand shell of colloidal nanoparticles has been an important pursuit in solar energy conversion. While charge transport through ligand shells of nanoparticle films has been studied intensely in static dry and electrochemical systems, its influence on charge transfer kinetics in dispersed colloidal systems has received relatively less attention. This work reports the oxidation of amine passivated tungsten oxide nanoparticles by an organically soluble tris-(1,10-phenanthroline) iron(III) derivative.

Electrodeposited cobalt-sulfide catalyst for electrochemical and photoelectrochemical hydrogen generation from water.

A cobalt-sulfide (Co-S) film prepared via electrochemical deposition on conductive substrates is shown to behave as an efficient and robust catalyst for electrochemical and photoelectrochemical hydrogen generation from neutral pH water. Electrochemical experiments demonstrate that the film exhibits a low catalytic onset overpotential (η) of 43 mV, a Tafel slope of 93 mV/dec, and near 100% Faradaic efficiency in pH 7 phosphate buffer. Catalytic current densities can approach 50 mA/cm(2) and activity is maintained for at least 40 h.

Modulation of gene expression via disruption of NF-kappaB signaling by a bacterial small molecule.

The control of innate immune responses through activation of the nuclear transcription factor NF-kappaB is essential for the elimination of invading microbial pathogens. We showed that the bacterial N-(3-oxo-dodecanoyl) homoserine lactone (C12) selectively impairs the regulation of NF-kappaB functions in activated mammalian cells. The consequence is specific repression of stimulus-mediated induction of NF-kappaB-responsive genes encoding inflammatory cytokines and other immune regulators.