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We investigated the long-term clinical results of total elbow arthroplasty (TEA) by cementless fixation of alumina ceramic unlinked elbow prostheses (J-alumina ceramic elbows: JACE) for the reconstruction of elbow joints with rheumatoid arthritis (RA). Seventeen elbows in 17 patients (aged 44-72 years, average 54.8) replaced by JACE TEA without bone cement were investigated. The average follow-up period was 10.7 (range, 1.0-19.3) years. Clinical conditions of each elbow before and after surgery were assessed according to the Mayo Elbow Performance Index (MEPI). Radiographic loosening was defined as a progressive radiolucent line of more than 1 mm that was completely circumferential around the intramedullary stem. The average MEPI significantly improved from 46.8 points preoperatively to 66.8 points at final follow-up (p=0.0226). However, aseptic loosening was noted in 10 of 17 elbows (58.8%) and revision surgery was required in 7 (41.2%). Most loosening was observed on the humeral side. With radiographic loosening and revision surgery defined as the end points, the likelihoods of prosthesis survival were 41.2% and 51.8%, respectively, up to 15 years by Kaplan-Meier analysis. The clinical results of JACE implantation without bone cement were disappointing, with high revision and loosening rates of the humeral component.

We present an investigation of the structure of $^{13}$Be obtained via a kinematically complete measurement of the (p,pn) reaction in inverse kinematics at 265 MeV/nucleon. The relative energy spectrum of $^{13}$Be is compared to Transfer-to-the-Continuum calculations which use as structure inputs the overlaps of the $^{14}$Be ground-state wave function, computed in a three-body model, with the unbound states of the $^{13}$Be residual nucleus. The key role of neutron p-wave orbital in the interpretation of the low-relative-energy part of the spectrum is discussed.

To explore the formation of noncollinear magnetic configurations in materials with strongly correlated electrons, we derive a noncollinear LSDA + U model involving only one parameter U , as opposed to the difference between the Hubbard and Stoner parameters U − J . Computing U in the constrained random phase approximation, we investigate noncollinear magnetism of uranium dioxide UO 2 and find that the spin-orbit coupling (SOC) stabilizes the 3 k ordered magnetic ground state. The estimated SOC strength in UO 2 is as large as 0.73 eV per uranium atom, making spin and orbital degrees of freedom virtually inseparable. Using a multipolar pseudospin Hamiltonian, we show how octupolar and dipole-dipole exchange coupling help establish the 3 k magnetic ground state with canted ordering of uranium f orbitals. The cooperative Jahn-Teller effect does not appear to play a significant part in stabilizing the noncollinear 3 k state, which has the lowest energy even in an undistorted lattice. The choice of parameter U in the LSDA + U model has a notable quantitative effect on the predicted properties of UO 2 , in particular on the magnetic exchange interaction and, perhaps trivially, on the band gap: The value of U = 3.46 eV computed fully ab initio delivers the band gap of 2.11 eV in good agreement with experiment, and a balanced account of other pertinent energy scales.

Production cross sections of residual nuclei via proton-and deuteron-induced spallation reactions on 91,92 Y, 92,93 Zr, and 93,94 Nb at projectile energies Production cross sections of residual nuclei via proton-and deuteron-induced spallation reactions on $^{91,92}$Y,$^{92,93}$Zr,and $^{93,94}$Nb at projectile energies around 100 MeV/nucleon were measured in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Noticeable jumps in the measured cross sections of isotone production appear between the neutron numbers N =51 and 50 for target nuclei with the initial neutron number N$_{init}$ =53 ($^{92}$Y, $^{93}$Zr, and $^{94}$Nb), while such jump is not clearly seen for target nuclei with N$^{init}$=52($^{91}$Y,$^{92}$Zr, and $^{93}$Nb). The measured isotopic production cross sections are compared with PHITS calculations considering both the intranuclear cascade and evaporation processes in order to benchmark the reaction models.

Magnetic reconnection is a process whereby magnetic field lines in different directions "reconnect" with each other, resulting in the rearrangement of magnetic field topology together with the conversion of magnetic field energy into the kinetic energy (K.E.) of energetic particles. This process occurs in magnetized astronomical plasmas, such as those in the solar corona, Earth's magnetosphere, and active galactic nuclei, and accounts for various phenomena, such as solar flares, energetic particle acceleration, and powering of photon emission. In the present study, we report the experimental demonstration of magnetic reconnection under relativistic electron magnetization situation, along with the observation of power-law distributed outflow in both electron and proton energy spectra. Through irradiation of an intense laser on a "micro-coil", relativistically magnetized plasma was produced and magnetic reconnection was performed with maximum magnetic field 3 kT. In the downstream outflow direction, the non-thermal component is observed in the high-energy part of both electron and proton spectra, with a significantly harder power-law slope of the electron spectrum (p = 1.535 +/- 0.015) that is similar to the electron injection model proposed to explain a hard emission tail of Cygnus X-1, a galactic X-ray source with the same order of magnetization. The obtained result showed experimentally that the magnetization condition in the emitting region of a galactic X-ray source is sufficient to build a hard electron population through magnetic reconnection., Comment: 25 pages, 10 figures