[en] This paper reports direct formation of Y₁Ba₂Cu₃O_7-x films on Cu substrates by electrophoretic deposition. Electrophoretic deposition was carried out using presintered Y₁Ba₂Cu₃O_7-x powder dispersed in distilled acetone. The deposited films were annealed in air at 900 degrees C. The authors succeeded in obtaining superconducting Y₁Ba₂Cu₃O_7-x films on Cu substrates. The films on Cu plates and Cu film/YSZ exhibited zero resistance state at 66 K and 76 K respectively. Interfacial chemical reactions at the Y₁Ba₂Cu₃O_7-x/Cu interface are discussed. The achievement of the zero resistance state is considered to be due to the reduction of the interfacial reactions

[en] Microtubule (MT) gliding on a kinesin-coated surface is a promising nanoactuator to manipulate nanomaterials in microfluidic environments. However, controllability of motors with respect to velocity, direction, and lifetime has been challenging for engineering purposes. Here, we used fluorescence excitation to control the MT velocity on a photolithographically patterned gold surface. The excitation wavelength was selected to match that used for the observation of MTs. Since a resistance temperature detector (RTD) was integrated on the assay substrate on which kinesin motors were coated, in situ temperature monitoring was implemented. Compared with the velocity of gliding MTs on the bare glass surface, the velocity increased by 1.8-fold on the gold-coated surface with the increase of temperature of 10.4 °C, which was caused by irradiance of 13.5 W · cm"−"2. We achieved repetitive velocity control, which was solely caused by the increase of temperature, i.e., irradiation energy. This key technology development enables reversible and localized velocity control of MT gliding, which can be easily integrated in nanosystems driven by kinesin motors. (paper)

[en] Among clinical treatments for type 1 diabetes mellitus, the transplantation of islets of Langerhans to the portal vein of the hepar is a commonly used treatment for glucose homeostasis. Islet purification using the density gradient of a solution in a centrifuge separator is required for safety and efficiency. In the purification, the number of tissues to be transplanted is reduced by removing the acinar tissue and gathering the islet from the digest of pancreas. However, the mechanical effects on the fracture of islets in the centrifuge due to fluid dynamic stress are a serious problem in the purification process. In this study, a preliminary experiment using a cylindrical rotating viscometer with a simple geometry is conducted in order to systematically clarify the effect of fluid dynamic stress on the fracture of islets. The effects of fluid dynamic stress on the islet configuration is quantitatively measured for various flow conditions, and a predictive fracture model is developed based on the experimental results. Furthermore, in the practical purification process in the COBE (Gambro BCT), which is widely used in clinical applications, we perform a numerical analysis of the fluid dynamic stress based on Navier-Stokes equations to estimate the stress conditions for islets. Using the fracture model and numerical analysis, the islet fracture characteristics using the COBE are successfully investigated. The results obtained in this study provide crucial information for the purification of islets by centrifuge in practical and clinical applications

[en] MeV quasi-mono-energetic proton beam is produced by a combination of a synchronous radio frequency (rf) electric field and laser-plasma ion acceleration. The experiment was carried out at the Kansai Photon Science Institute, JAEA, using the Ti:Sapphire laser system called J-KAREN. The proton beam is emitted normal to the rear surface of the thin polyimide target of the thickness 7.5 μm irradiated at peak intensity of 4x10¹⁸ W/cm². The energy spread is compressed from 100% to less than 11% at FWHM by the rf field. The focusing and defocusing effect of the transverse direction is also observed. These are also studied by a Monte Carlo simulation. The relation between the transverse focusing and the energy spectrum of the phase-rotated beam is systematically shown by the simulation