Post-Newtonian Hydrodynamic Equations Using the (3+1) Formalism in General Relativity

Using the (3+1) formalism in general relativity, we perform the post-Newtonian(PN) approximation to clarify what sort of gauge condition is suitable for numerical analysis of coalescing compact binary neutron stars and gravitational waves from them. We adopt a kind of transverse gauge condition to determine the shift vector. On the other hand, for determination of the time slice, we adopt three slice conditions(conformal slice, maximal slice and harmonic slice) and discuss their properties. Using these conditions, the PN hydrodynamic equations are obtained up through the 2.5PN order including the quadrupole gravitational radiation reaction. In particular, we describe methods to solve the 2PN tensor potential which arises from the spatial 3-metric. It is found that the conformal slice seems appropriate for analysis of gravitational waves in the wave zone and the maximal slice will be useful for describing the equilibrium configurations. The PN approximation in the (3+1) formalism will be also useful to perform numerical simulations using various slice conditions and, as a result, to provide an initial data for the final merging phase of coalescing binary neutron stars which can be treated only by fully general relativistic simulations.Comment: 40 pages, TeX file using phyzzx, no figures, to appear in Prog. Theor. Phy

Toward a No-Go Theorem for an Accelerating Universe through a Nonlinear Backreaction

The backreaction of nonlinear inhomogeneities to the cosmic expansion is re-analyzed in the framework of general relativity. Apparent discrepancies regarding the effect of the nonlinear backreaction, which exist among the results of previous works in different gauges, are resolved. By defining the spatially averaged matter energy density as a conserved quantity in the large comoving volume, it is shown that the nonlinear backreaction neither accelerates nor decelerates the cosmic expansion in a matter-dominated universe. The present result in the Newtonian gauge is consistent with the previous results obtained in the comoving synchronous gauge. Although our work does not give a complete proof, it strongly suggests the following no-go theorem: No cosmic acceleration occurs as a result of the nonlinear backreaction via averaging.Comment: 6 pages (PTPTeX); accepted for publication in Prog. Theor. Phys; minor changes to match published versio

薬剤性過敏症症候群(DIHS)の皮疹部においてCD3陽性T細胞数に対するFoxP3陽性制御性T細胞数の割合は増加している

博士（医学）・甲第604号・平成25年11月27日© 2014 British Association of Dermatologists / The definitive version is available at http://onlinelibrary.wiley.com

Failure of DNA double-strand break repair by tau mediates Alzheimer’s disease pathology in vitro

DNA double-strand break (DSB) is the most severe form of DNA damage and accumulates with age, in which cytoskeletal proteins are polymerized to repair DSB in dividing cells. Since tau is a microtubule-associated protein, we investigate whether DSB is involved in tau pathologies in Alzheimer’s disease (AD). First, immunohistochemistry reveals the frequent coexistence of DSB and phosphorylated tau in the cortex of AD patients. In vitro studies using primary mouse cortical neurons show that non-p-tau accumulates perinuclearly together with the tubulin after DSB induction with etoposide, followed by the accumulation of phosphorylated tau. Moreover, the knockdown of endogenous tau exacerbates DSB in neurons, suggesting the protective role of tau on DNA repair. Interestingly, synergistic exposure of neurons to microtubule disassembly and the DSB strikingly augments aberrant p-tau aggregation and apoptosis. These data suggest that DSB plays a pivotal role in AD-tau pathology and that the failure of DSB repair leads to tauopathy

Validity of strong lensing statistics for constraints on the galaxy evolution model

We examine the usefulness of the strong lensing statistics to constrain the evolution of the number density of lensing galaxies by adopting the values of the cosmological parameters determined by recent WMAP observation. For this purpose, we employ the lens-redshift test proposed by Kochanek (1992) and constrain the parameters in two evolution models, simple power-law model characterized by the power law indexes $nu_{n}$ and $\nu_{v}$ and the evolution model by Mitchell et al. (2005) based on CDM structure formation scenario. We use the well-defined lens sample from the Sloan Digital Sky Survey (SDSS) and this is similarly sized samples used in the previous studies. Furthermore, we adopt the velocity dispersion function of early-type galaxies based on SDSS DR1 and DR5. It turns out that the indexes of power-law model are consistent with the previous studies, thus our results indicate the mild evolution in the number and velocity dispersion of early-type galaxies out to z = 1. However we found that the values for p and q used by Mitchell et al. are inconsistent with the presently available observational data. More complete sample is necessary to withdraw more realistic determination on these parameters.Comment: Accepted to MNRAS, 7 pages, 3 figure

Equation of motion for relativistic compact binaries with the strong field point particle limit : Formulation, the first post-Newtonian and multipole terms

We derive the equation of motion for the relativistic compact binaries in the post-Newtonian approximation taking explicitly their strong internal gravity into account. For this purpose we adopt the method of the point particle limit where the equation of motion is expressed in terms of the surface integrals. We examine carefully the behavior of the surface integrals in the derivation. As a result, we obtain the Einstein-Infeld-Hoffman equation of motion at the first post-Newtonian (1PN) order, and a part of the 2PN order which depends on the quadrupole moments and the spins of component stars. Hence, it is found that the equation of motion in the post-Newtonian approximation is valid for the compact binaries by a suitable definition of the mass, spin and quadrupole moment.Comment: revised version. 27pages, three tables, revtex. Some errors have been corrected and some explanations have been adde

Propagation of gravitational waves from slow motion sources in a Coulomb type potential

We consider the propagation of gravitational waves generated by slow motion sources in Coulomb type potential due to the mass of the source. Then, the formula for gravitational waveform including tail is obtained in a straightforward manner by using the spherical Coulomb function. We discuss its relation with the formula in the previous work.Comment: 13 pages, no figures, to be published in Phys. Rev.

Equation of motion for relativistic compact binaries with the strong field point particle limit : the second and half post-Newtonian order

We study the equation of motion appropriate to an inspiralling binary star system whose constituent stars have strong internal gravity. We use the post-Newtonian approximation with the strong field point particle limit by which we can introduce into general relativity a notion of a point-like particle with strong internal gravity without using Dirac delta distribution. Besides this limit, to deal with strong internal gravity we express the equation of motion in surface integral forms and calculate these integrals explicitly. As a result we obtain the equation of motion for a binary of compact bodies accurate through the second and half post-Newtonian (2.5 PN) order. This equation is derived in the harmonic coordinate. Our resulting equation perfectly agrees with Damour and Deruelle 2.5 PN equation of motion. Hence it is found that the 2.5 PN equation of motion is applicable to a relativistic compact binary.Comment: 48 pages, revtex, accepted for publication in Phys. Rev.

Interface design dividing physical findings into medical and trauma findings facilitates clinical document entry in the emergency department: A prospective observational study.

PURPOSE: The interface design and its effect on workflow are key determinants of the usability of electronic medical records (EMRs) in the emergency department (ED). However, whether the overall clinical care can be improved by dividing the interface design of physical findings into medical and trauma findings is unknown. We previously developed an EMR system in which the checkpoints were separated into different sections according to the body part. Herein, we modified this EMR system by remaking the interface design specifically for trauma patients, and evaluated its performance. METHODS: This study was undertaken in a single-center ED between October 2014 and September 2015. In the modified EMR system, all trauma findings are displayed together on the screen, according to the Japan Advanced Trauma Evaluation and Care. We compared the time to final documentation entry and the length of ED stay between the previous (used in the first 6 months) and current systems (used in the latter 6 months). Furthermore, we stratified the patients by triage levels. RESULTS: The study involved 2141 patients (934 and 1207 assessed using the previous and modified EMR systems, respectively). The modified EMR in trauma patients significantly decreased the time to final documentation entry from 131.5 [interquartile range, 86.8-207.3] to 115 [78.8-161] min (p = 0.049). When stratifying trauma patients by triage level, significantly shorter clinical documentation times were observed with the modified EMR system in levels 2 (emergency) and 3 (urgent). CONCLUSIONS: Using different interfaces for trauma findings shortened the time for clinical documentation for trauma patients