Nonequilibrium process in the σ\sigma model and chemical relaxation time in a homogeneous pionic gas

In a homogeneous pionic gas system, chemical nonequilibrium process is considered to understand its effect in the expansion processes that are realized immediately after heavy ion collisions. The chemical relaxation time is calculated by incorporating the $\pi+\pi \leftrightarrow \pi+\pi+\pi+\pi$ reaction, which is given in the second order of perturbation in the $\sigma$ model. The $\pi+\pi \leftrightarrow \pi+\pi+\pi+\pi$ reaction is assumed to be less frequent than the $\pi+\pi \leftrightarrow \pi+\pi$ scattering that is expected to establish the local equilibrium, and hydrodynamical equation is solved for various initial conditions. It is shown that the relaxation time is of the order of 100fm and does not have a significant effect on the expansion process, which implies that the pion number freezeout takes place at an early stage of the expansion.Comment: 17 pages, LaTeX type, figures available on request, e-mail address [email protected]

Sustainability of Open Systems Based on an Agent Model with Fluctuation

In IT technology, especially in software development, open development system has been proven to be useful. Linux, apache software and GNU software are typical examples. Still, it is also known that there are many open software development projects that failed or stopped developments. So far, it has not been clearly known what the key factor is to give the difference between the successful open projects and the ones that fails. In this report, we analyze the sustainability of open systems based on an agent model that explicitly takes the effect of fluctuation into account. Although the model is simple, it is shown that the system with many less-powered leaders is more stable than a system with small number of powerful leaders

ANALYSIS OF THE GROWTH OF SOCIAL NETWORKING SERVICES BASED ON THE ISING TYPE AGENT MODEL

In recent years, social networking services such as facebook, twitter and some kind of blogs have been growing, obtaining more and more users and having larger impact on many areas of social activities. In these services, it has been noted that network externality plays an important role. The utility of a service depends on the number of users that use the service. In general, the growth curve of the number of the users etc. is nonlinear. So far, however, this nonlinearity has not been understood quantitatively. By applying the nearest neighboring agent model called Ising type agent model, we analyze the growth of a blog type social networking service. It is shown that the growth curve is quantitatively reproduced covering the whole range from the initial service-starting stage to the final saturating stage, despite the fact that the model has only two parameters. This means that the model is promising as a starting point of analyzing the growth and the impact of social networking services

心房細動患者における、脳卒中と出血のリスクに対する高血圧と収縮期血圧の関係について：伏見AFレジストリから

京都大学0048新制・論文博士博士(医学)乙第13370号論医博第2207号新制||医||1047(附属図書館)(主査)教授 大鶴 繁, 教授 中山 健夫, 教授 髙橋 良輔学位規則第4条第2項該当Doctor of Medical ScienceKyoto UniversityDFA

Huge electron-hole exchange interaction in aluminum nitride

Optical spectroscopy is performed for c-plane homoepitaxial aluminum nitride (AlN) films. The temperature dependence of the polarization-resolved photoluminescence spectra reveals the exciton fine structure. The experimental results demonstrate that the electron-hole exchange interaction energy (j) in AlN is j=6.8 meV, which is the largest value for typical III-V and II-VI compound semiconductors. We propose the effective interatomic distance as the criterion of the electron-hole exchange interaction energy, revealing a universal rule. This study should encourage potential applications of excitonic optoelectronic devices in nitride semiconductors similar to those using II-VI compound semiconductors

How Cervical Reconstruction Surgery Affects Global Spinal Alignment.

BACKGROUND:There have been no reports describing how cervical reconstruction surgery affects global spinal alignment (GSA). OBJECTIVE:To elucidate the effects of cervical reconstruction for GSA through a retrospective multicenter study. METHODS:Seventy-eight patients who underwent cervical reconstruction surgery for cervical kyphosis were divided into a Head-balanced group (n = 42) and a Trunk-balanced group (n = 36) according to the values of the C7 plumb line (PL). We also divided the patients into a cervical sagittal balanced group (CSB group, n = 18) and a cervical sagittal imbalanced group (CSI group, n = 60) based on the C2 PL-C7 PL distance. Various sagittal Cobb angles and the sagittal vertical axes were measured before and after surgery. RESULTS:Cervical alignment was improved to achieve occiput-trunk concordance (the distance between the center of gravity [COG] PL, which is considered the virtual gravity line of the entire body, and C7 PL < 30 mm) despite the location of COG PL and C7PL. A subsequent significant change in thoracolumbar alignment was observed in Head-balanced and CSI groups. However, no such significant change was observed in Trunk-balanced and CSB groups. We observed 1 case of transient and 1 case of residual neurological worsening. CONCLUSION:The primary goal of cervical reconstruction surgery is to achieve occiput-trunk concordance. Once it is achieved, subsequent thoracolumbar alignment changes occur as needed to harmonize GSA. Cervical reconstruction can restore both cervical deformity and GSA. However, surgeons must consider the risks and benefits in such challenging cases

Is this a new type of primary prosopagnosia, both progressive and apperceptive?

Prosopagnosia, the inability to recognize faces, has a history going back to Charcot and Hughlings-Jackson, but was first named by Bodamer in 1947. Its anatomical loci are still unclear. However, progressive prosopagnosia is normally linked to right dominant temporal lobe atrophy, and diagnosed as part of frontotemporal lobar degeneration. Here we report a case of prosopagnosia linked to posterior cortical atrophy. Although case reports of posterior cortical atrophy-prosopagnosia do already exist, it is normally described as an accessory symptom. The interest of our own posterior cortical atrophy patient, possibly the first such case, is that he had a rare apperceptive type of prosopagnosia unrelated to the associative, frontotemporal lobar degeneration-type

Frequent Loss of Genome Gap Region in 4p16.3 Subtelomere in Early-Onset Type 2 Diabetes Mellitus

A small portion of Type 2 diabetes mellitus (T2DM) is familial, but the majority occurs as sporadic disease. Although causative genes are found in some rare forms, the genetic basis for sporadic T2DM is largely unknown. We searched for a copy number abnormality in 100 early-onset Japanese T2DM patients (onset age <35 years) by whole-genome screening with a copy number variation BeadChip. Within the 1.3-Mb subtelomeric region on chromosome 4p16.3, we found copy number losses in early-onset T2DM (13 of 100 T2DM versus one of 100 controls). This region surrounds a genome gap, which is rich in multiple low copy repeats. Subsequent region-targeted high-density custom-made oligonucleotide microarray experiments verified the copy number losses and delineated structural changes in the 1.3-Mb region. The results suggested that copy number losses of the genes in the deleted region around the genome gap in 4p16.3 may play significant roles in the etiology of T2DM