ARHGAP22 is a RhoGAP protein comprising an N-terminal PH domain, a RhoGAP domain and a C-terminal coiled-coil domain. It has recently been identified as an Akt substrate that binds 14-3-3 proteins in response to treatment with growth factors involved in cell migration. We used a range of biophysical techniques to investigate the weak interaction between 14-3-3 and a truncated form of ARHGAP22 l...

soil samples were collected from seven sites in and around the metropolitan area of mexicocity. the locations were chosen as possible sources of fugitive dusts which contribute to suspended particulate matter in the atmosphere of mexico city. x-ray fluorescence (xrf) was used to determine the concentrations of several major elements (si, k, ca, ti, mn, and fe), as well as of other trace element...

In recent years the variability of the cosmic ray flux has become one of the main issues interpreting cosmogenic elements and especially their connection with climate. In this review, an interdisciplinary team of scientists brings together our knowledge of the evolution and modulation of the cosmic ray flux from its origin in the Milky Way, during its propagation through the heliosphere, up to ...

Electrochemically deposited CdS nanoparticles (NPs) were formed using porous silicon (PS) as a substrate/electrode. The structure, electronic behavior of the CdS NPs and the interaction between CdS-PS were systematically examined using electron microscope, X-ray diffraction and X-ray absorption fine structure (XAFS) at S K-edge and Si K-edge. The optical luminescence behavior of the nanocomposi...

Synchrotron-based x-ray radiation has been utilized to measure time-resolved x-ray excited optical luminescence (TR-XEOL) from InGaN/GaN multiple quantum well (MQW) structures. Excess carrier recombination lifetimes were determined for MQWs grown on conventional c-plane as well as on non-polar m-plane substrates. In addition, the simultaneous measurement of XEOL and x-ray fluorescence reveals a...

Normal galaxies are faint and complex X-ray sources that provide very powerful probes for fundamental astrophysical questions. Examples include: the study of populations of X-ray emitting sources; the study of the entire spectrum of black-hole phenomena; and galaxy formation and evolution in interaction with the surrounding environment. While exciting, all these fields require Chandra sub-arcse...

Atomic-layer 2D crystals have unique properties that can be significantly modified through interaction with an underlying support. For epitaxial graphene on SiC(0001), the interface strongly influences the electronic properties of the overlaying graphene. We demonstrate a novel combination of x-ray scattering and spectroscopy for studying the complexities of such a buried interface structure. T...

The magnetic and electronic properties of single-molecule magnets are studied by X-ray absorption spectroscopy and X-ray magnetic circular dichroism. We study the magnetic coupling of ultrathin Co and Ni films that are epitaxially grown onto a Cu(100) substrate, to an in situ deposited submonolayer of TbPc2 molecules. Because of the element specificity of the X-ray absorption spectroscopy we ar...

We used photon pulses from an x-ray free-electron laser to study ultrafast x-ray-induced transitions of graphite from solid to liquid and plasma states. This was accomplished by isochoric heating of graphite samples and simultaneous probing via Bragg and diffuse scattering at high time resolution. We observe that disintegration of the crystal lattice and ion heating of up to 5 eV occur within t...

This paper demonstrates the enhanced capability of single polarity charge sensing, the 3-dimensional position sensing technique, developed at the University of Michigan and previously successfully demonstrated on CdZnTe detectors, to improve the spectroscopic performance of HgI2 and to extend its range for spectrometry to an unprecedented thickness of 10 mm. Energy resolutions of close to 1% FW...