Raman spectroscopy studies of dopant activation and free electron density of In(0.53)Ga(0.47)As via sulfur monolayer doping.

We present a Raman spectroscopy study of electron-phonon coupling in In0.53Ga0.47As epilayers doped via the sulfur-monolayer doping method.

Imaging local electronic corrugations and doped regions in graphene.

Electronic structure heterogeneities are ubiquitous in two-dimensional graphene and profoundly impact the transport properties of this material. Here we show the mapping of discrete electronic domains within a single graphene sheet using scanning transmission X-ray microscopy in conjunction with ab initio density functional theory calculations. Scanning transmission X-ray microscopy imaging provides a wealth of detail regarding the extent to which the unoccupied levels of graphene are modified by corrugation, doping and adventitious impurities, as a result of synthesis and processing.

The Pseudomonas aeruginosa quorum-sensing molecule N-3-(oxododecanoyl)-L-homoserine lactone inhibits T-cell differentiation and cytokine production by a mechanism involving an early step in T-cell activation.

The Pseudomonas aeruginosa quorum-sensing molecule N-3-(oxododecanoyl)-L-homoserine lactone (OdDHL) has been reported to have immunomodulatory activity in several systems, although the mechanism of that activity remains to be fully characterized. We demonstrate here, using a defined in vitro model of antigen responses by T-cell receptor (TCR)-transgenic mouse splenic CD4 T cells, that the effect of OdDHL on activation and cytokine production is complete within 4 h of antigen or mitogen stimulation and does not depend on the insertion of OdDHL in the cell membrane, despite a previous report that immunosuppression by homoserine lactones required a minimum acyl chain length of 11 carbons (S. R.