For phonons propagating in a crystal at low temperature, we develop a phonon reflection model and an analysis framework to fully understand reflection peaks from underlying physics principles. Our study shows that the specular reflection structure of peaks contains detailed information about properties of the crystal material, and provides a solid quantitative link between phonon theory and experimental signals. For both kinds of experiments that either use crystal as a particle detector or as a target material for study, this analysis provides a novel and essential method to understand the experimental signatures.
  High frequency (HF) block can quickly and reversibly stop nerve conduction. We hypothesized HF block at the sciatic nerve would minimize nociception by preventing neuropathic signals from reaching the central nervous system.
 
  Lewis rats were implanted with a constriction cuff and a distal cuff electrode around their right sciatic nerve. Tactile sensitivity was evaluated using the 50% paw withdrawal threshold determined using Chaplan's method for von Frey monofilaments. Over the course of 49 days, the 50% paw withdrawal threshold was measured 1) before HF block, 2) during HF block (50 kHz, 3 Vpp), and 3) after HF block. Gait was observed and scored before and during block. At end point, HF block efficacy was directly evaluated using additional cuff electrodes to elicit and record compound neural action potentials across the HF blocking cuff.
 
  At days 7 and 14 days post-operation, tactile sensitivity was significantly lower during HF block compared to before and after block (p < 0.005). Additionally, an increase in gait disability was not visually observed during HF block.
 
  HF block can reduce tactile sensitivity in a limb with a neuropthic injury in a rapidly reversible fashion.
 HF block can reduce tactile sensitivity in a limb with a neuropthic injury in a rapidly reversible fashion.Magnetotransport studies have established the existence of exotic electronic properties in materials of technological and fundamental interest. However, measurements of the Shubnikov-de Haas oscillations, intended to reveal information about Fermi surfaces, have mostly been carried out in magnetic fields perpendicular to the applied currents. Here, using magnetic fields not only perpendicular but also parallel to the applied currents in a given contact configuration, we investigated the anisotropic magnetotransport and the anisotropic Fermi surface properties of Bi2-xSnxTe3(0 ≤ x ≤ 0.0075) and Bi2Se3. While the magnetotransport properties of Bi2Te3and Bi2Se3were nearly isotropic, Bi1.995Sn0.005Te3exhibited quite anisotropic features. These observations are attributed to the nonparabolicity of the associated bands, which evolved to more anisotropic band structures with Sn concentration. This sensitivity of the band anisotropy was rather unexpected because only a small number of dopants are known to increase disorder levels in the degenerate region. Our approach, using two different magnetic field directions in the measurements of the Shubnikov-de Haas oscillations, is a simple and easily adoptable method for shedding more light on the Fermi surfaces of functional materials.Efficient nucleotide import is critical to fuel the reverse DNA synthesis that takes place within the HIV-1 capsid. However, the mechanism by which the HIV-1 capsid imports nucleotides is presently unclear. In this work, we carry out a series of Brownian diffusion simulations to elucidate the nucleotide import process through the hexamer pores of the HIV-1 capsid. Our simulations reveal a significant role of the electrostatic field in the import process and the mechanism by which deoxynucleoside triphosphates (dNTPs) diffuse through the arginine ring specifically, how IP6s and ATPs, though competing with dNTPs for binding at the pore of the arginine ring, end up accelerating the dNTP import rate by thousands of folds so that it is sufficiently high to fuel the encapsidated DNA synthesis.This study investigated the feasibility of dosimetric measurements using Al2O3C optically stimulated luminescence (OSL) dosimeters during fluoroscopy-guided procedures. The linearity and energy dependence of Al2O3C OSL dosimeters were evaluated, and the air kerma rate at the operator's position was measured. The response of Al2O3C OSL dosimeters to short, repetitive irradiations was compared to that of long uninterrupted irradiation. The change in response of the Al2O3C OSL dosimeter under automatic exposure rate control (AERC) was evaluated with the use of various thicknesses of polymethyl-methacrylate (PMMA) plates (15-30 cm). The Al2O3C OSL dosimeters could detect 5 µGy and showed good linearity in doses of ≥ 10 µGy (R² 0.997-0.999, p 0.05). Despite a high energy dependence on the low energy beam used in fluoroscopy, the change in relative response of the Al2O3C OSL dosimeter under AERC was within 5.7% depending on the thickness of the PMMA plates. Dosimetric measurement using Al2O3C OSL dosimeters for patients and operators is feasible. However, one should be cautious about high standard deviations when measuring small doses of ≤ 20 µGy using Al2O3C OSL dosimeters.  https://www.selleckchem.com/products/oicr-9429.html  It is essential to perform intensive bleaching before measuring very small doses to minimize pre-irradiation counts.In this study, we employ bulk electronic properties characterization and x-ray scattering/spectroscopy techniques to map the structural, magnetic and electronic properties of (Eu1-xCax)2Ir2O7as a function of Ca-doping. As expected, the metal-insulator transition temperature, TMIT, decreases with Ca-doping until a metallic state is realized down to 2 K. In contrast, the onset of magnetic order at TAFMbecomes decoupled from TMITand (likely short-range) antiferromagnetism persists into the metallic regime. This decoupling is understood as a result of the onset of an electronically phase separated state, the occurrence of which seemingly depends on both synthesis method and rare earth site magnetism. PDF analysis suggests that electronic phase separation occurs without accompanying chemical phase segregation or changes in the short-range crystallographic symmetry while synchrotron x-ray diffraction confirms that there is no change in the long-range crystallographic symmetry. X-ray absorption measurements confirm the Jeff = ½ character of (Eu1-xCax)2Ir2O7.