Description: This article discusses AGC kinase genes. Abstract: The AGC protein kinase family (cAMP-dependent protein kinases A, cGMP-dependent protein kinases G, and phospholipid-dependent protein kinases C) have important roles regulating growth and development in animals and fungi. They are activated via lipid second messengers by 3-phosphoinositide-dependent protein kinase coupling lipid signals to phosphorylation of the AGC kinases. These phosphorylate downstream signal transduction protein targets. AGC kiinases are becoming better studied in plants, especially in Arabidopsis (Arabidopsis thaliana), where specific AGC kinases have been shown to have key roles in regulating growth signal pathways. The authors report here the isolation and characterization of the first AGC kinase gene identified in Medicago truncatula, MtIRE. It was cloned by homology with the Arabidopsis INCOMPLETE ROOT HAIR ELONGATION (IRE) gene. Semiquantitative reverse transcription-polymerase chain reaction analysis shows that, unlike its Arabidopsis counterpart, MtIRE is not expressed in uninoculated roots, but is expressed in root systems that have been inoculated with Sinorhizobium meliloti and are developing root nodules. MtIRE expression is also found in flowers. Expression analysis of a time course of nodule development and of nodulating root systems of many Medicago nodulation mutants shows MtIRE expression correlates with infected cell maturation during nodule development. During ...

Description: This article discusses the solubility of polycyclic aromatic hydrocarbons in pure and organic solvent mixtures. Abstract: This work updates Vols. 54, 58, and 59 in the IUPAC Solubility Data Series and presents solubility data for polycyclic aromatic hydrocarbon solutes dissolved in ternary organic solvent mixtures. Published solubility data for anthracene, phenanthrene, and pyrene that appeared in the primary literature between 1995 to the end of 2011 are compiled and critically evaluated. Experimental solubility data for 119 different solute-ternary solvent systems are included in the volume. Solubility data published prior to 1995 were contained in three earlier volumes (Vols. 54, 58, and 59) and are not repeated here.

Description: This article discusses three-coordinate Au(I) phosphine complexes. Abstract: DFT calculations were used to optimize the phosphorescent excited state of three-coordinate [Au(PR3)3]+ complexes. The results indicate that the complexes rearrange from their singlet ground-state trigonal planar geometry to a T-shape in the lowest triplet luminescent excited state. The optimized structure of the exciton contradicts the structure predicted based on the AuP bonding properties of the ground-state HOMO and LUMO. The rearrangement to T-shape is a Jahn-Teller distortion because an electron is taken from the degenerate e' (5dxy, 5dx2-y2) orbital upon photoexcitation of the ground-state D3h complex. The calculated UV absorption and visible emission energies are consistent with the experimental data and explain the large Stokes' shifts while such correlations are not possible in optimized models that constrained the exciton to the ground-state trigonal geometry.

Description: This article discusses K-shell ionization by low-velocity ions. K-shell x-ray-production measurements are reported for protons, deuterons, and alpha particles incident on thin foils of copper, niobium, silver, and antimony. In the velocity range of the experiments, which correspond to 100-600 keV/u, the energy of ionization was as large as 10% of the bombarding energy. The inferred dependence of the excitation process on the projectile mass, atomic number, and energy is compared with theoretical estimates of a low-velocity ionization threshold, the binding effect, and the Coulomb-deflection effect. Precision of measurement is not great enough to discern unambiguously the threshold effect but the binding and Coulomb-deflection effects are clearly distinguished.

Description: This article discusses K-shell ionization elements Ca to Zn for 0.5 to 2.5-MeV/amu 14N-ion bombardment. Abstract: Target K-shell x-ray production cross sections, x-ray energy shifts, and Kβ/Kα ratios have been measured for 7-35-MeV 14N ions on thin solid films of Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn. Comparisons of the data were made with theoretical predictions obtained from the binary-encounter approximation and the planewave born approximation (PWBA). These theories were found to overpredict the experimental data by a factor of 10 at the lower energies. However, at the lower energies, the PWBA, with modifications for increased target electron binding, Coulomb deflection, target electron polarization, and relativistic effects produced results in good agreement with the experimental data was found which increases as the ratio of Z1/Z2 becomes larger. Corrections to the fluorescence yields attributable to multiple ionization processes and the addition of electron capture contributions to the previously indicated direct ionization theories produced results in excellent agreement with the experimental data with the exception of those for the light elements at the highest energies.