The upregulation of Prx I, Prx III and thioredoxin in lung cancer tissue may represent an attempt by tumour cells to adjust to the microenvironment in a manner that is advantageous to survival and proliferation.

The interactions of a hydrophilic surface with water can significantly influence the characteristics of the liquid water interface. In this manuscript, we explore this influence by studying the molecular structure of liquid water at a disordered surface with tunable surface-water interactions. We combine all-atom molecular dynamics simulations with a mean field model of interfacial hydrogen bonding to analyze the effect of surface-water interactions on the structural and energetic properties of the liquid water interface. We find that the molecular structure of water at a weakly interacting (i.e., hydrophobic) surface is resistant to change unless the strength of surface-water interactions is above a certain threshold. We find that below this threshold water's interfacial structure is homogeneous and insensitive to the details of the disordered surface, however, above this threshold water's interfacial structure is heterogeneous. Despite this heterogeneity, we demonstrate that the equilibrium distribution of molecular orientations can be used to quantify the energetic component of the surface-water interactions that contribute specifically to modifying the interfacial hydrogen bonding network. We identify this specific energetic component as a new measure of hydrophilicity, which we refer to as the intrinsic hydropathy.

In this work, we present a general computational method for characterizing the molecular structure of liquid water interfaces as sampled from atomistic simulations. With this method, the interfacial structure is quantified based on the statistical analysis of the orientational configurations of interfacial water molecules. The method can be applied to generate position dependent maps of the hydration properties of heterogeneous surfaces. We present an application to the characterization of surface hydrophobicity, which we use to analyze simulations of a hydrated protein. We demonstrate that this approach is capable of revealing microscopic details of the collective dynamics of a protein hydration shell.

The field-switching properties of NbO2/NbO or NbO2/(reduced NbO2) devices have been investigated. Under an applied electric field they switch from a high (≳10 kΩ) to a low (∼10 Ω) resistance in times shorter than 0.7 ns. For pulse durations of several ns, the current carrying capability is higher than 80 A. The switching mechanism appears to proceed in two stages: the field-assisted Poole-Frenkel mechanism for low applied field and thermal runaway. However, the unique switching properties of NbO2 could also be understood by a small poloron-conduction mechanism.

We present a simple model of aqueous interfacial molecular structure, and we use this model to isolate the effects of hydrogen bonding on the dielectric properties of the liquid water-vapor interface. We show that water's interfacial molecular structure can be understood by considering the orientational preferences of a single molecule immersed in the environment of the average interfacial density field. We illustrate that depth-dependent orientational anisotropy is determined by the geometric constraints of hydrogen bonding, and we show that the primary features of atomistic simulation data can be reproduced by assuming an idealized, perfectly tetrahedral hydrogen bonding geometry. We demonstrate that nonideal hydrogen bond geometries are required to account for variations in the orientational polarization and polarizability of the interface. Finally, we highlight that these properties contain significant contributions from a specific type of geometrically distorted three-body hydrogen bond defect that is preferentially stabilized at the interface.