Measurements of charge carrier mobilities and drift velocity saturation in bulk silicon of 〈1 1 1〉 and 〈1 0 0〉 crystal orientation at high electric fields

The mobility of electrons and holes in silicon depends on many parameters. Two of them are the electric field and the temperature. It has been observed previously that the mobility in the transition region between ohmic transport and saturation velocities is a function of the orientation of the crystal lattice.This paper presents a new set of parameters for the mobility as function of temperature and electric field for 〈1 1 1〉 and 〈1 0 0〉 crystal orientation. These parameters are derived from time of flight measurements of drifting charge carriers in planar p⁺nn⁺ diodes in the temperature range between −30 °C and 50 °C and electric fields of 2 × 10³ V/cm to 2 × 10⁴ V/cm.     

A Small RNA,UdsC, Interacts with the RpoHII mRNA and Affects the Motility and Stress Resistance of Rhodobacter sphaeroides

sRNAs have an important role in the regulation of bacterial gene expression. The sRNA, UdsC, of Rhodobacter sphaeroides is derived from the 3′ UTR of the RSP_7527 mRNA, which encodes a hypothetical protein. Here, we showed the effect of UdsC on the resistance of Rhodobacter sphaeroides to hydrogen peroxide and on its motility. In vitro binding assays supported the direct interaction of UdsC with the 5′ UTR of the rpoHII mRNA. RpoHII is an alternative sigma factor with an important role in stress responses in R. sphaeroides, including its response to hydrogen peroxide. We also demonstrated that RpoHII controls the expression of the torF gene, which encodes an important regulator of motility genes. This strongly suggested that the observed effect of UdsC on TorF expression is indirect and mediated by RpoHII.     

Coherent interaction of atoms with a beam of light confined in a light cage

Controlling coherent interaction between optical fields and quantum systems in scalable, integrated platforms is essential for quantum technologies. Miniaturise...     

Peculiar Thermal Features of Ce-Systems Around Their Critical Points

Some non-predicted thermal behavior observed in various Ce-lattice compounds close to their critical points are presented. From a comparison between phase diagrams driven by doping (x) and pressure, a pre-critical region (x^* < x < x_cr) is identified in the former group. Some systematic behaviors, observed in the specific heat (C_m/T) and the entropy gain, are recognized as characteristic features of that region. Different measured temperature dependencies of C_m/T are compared, detecting that the onset of the non-Fermi-liquid behavior occurs much closer to x^* than x_cr. In a detailed analysis of the evolution of the thermal dependence within the pre-critical region, a further change in the T dependence is frequently observed before to reach the critical point. A generalized power law function is proposed to compare different systems, which allows to identify a low temperature C_m/T(T) anomaly that only involves about 0.01 × R ln 2 of entropy.     

The human startle reflex and alcohol cue reactivity: Effects of early versus late abstinence.

This study investigated the human eyeblink startle reflex as a measure of alcohol cue reactivity. Alcohol-dependent participants early (n?=?36) and late (n?=?34) in abstinence received presentations of alcohol and water cues. Consistent with previous research, greater salivation and higher ratings of urge to drink occurred in response to the alcohol cues. Differential salivary and urge responding to alcohol versus water cues did not vary as a function of abstinence duration. Of special interest was the finding that startle response magnitudes were relatively elevated to alcohol cues, but only in individuals early in abstinence. Affective ratings of alcohol cues suggested that alcohol cues were perceived as aversive. Methodological and theoretical implications of the findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)