The Quiescent Intracluster Medium in the Core of the Perseus Cluster

Clusters of galaxies are the most massive gravitationally-bound objects in the Universe and are still forming. They are thus important probes of cosmological parameters and a host of astrophysical processes. Knowledge of the dynamics of the pervasive hot gas, which dominates in mass over stars in a cluster, is a crucial missing ingredient. It can enable new insights into mechanical energy injection by the central supermassive black hole and the use of hydrostatic equilibrium for the determination of cluster masses. X-rays from the core of the Perseus cluster are emitted by the 50 million K diffuse hot plasma filling its gravitational potential well. The Active Galactic Nucleus of the central galaxy NGC1275 is pumping jetted energy into the surrounding intracluster medium, creating buoyant bubbles filled with relativistic plasma. These likely induce motions in the intracluster medium and heat the inner gas preventing runaway radiative cooling; a process known as Active Galactic Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus cluster core, which reveal a remarkably quiescent atmosphere where the gas has a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s is found across the 60 kpc image of the cluster core. Turbulent pressure support in the gas is 4% or less of the thermodynamic pressure, with large scale shear at most doubling that estimate. We infer that total cluster masses determined from hydrostatic equilibrium in the central regions need little correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July

高齢者のフォワードランジにおける後脚の運動特性

フォワードランジ(forward lunge : 以下FL)の後脚は身体重心の前方移動の推進と後方移動の制動を担っている。今回、高齢者のFL動作における後脚の関節運動と片脚支持の重心動揺を測定し、後脚の運動とバランス機能の関連を明らかにすることを目的とした。高齢群は左右方向への重心動揺が大きく、床反力の左右成分においても若年群に比べて有意に大きな数値を示した。高齢者のFL動作における後脚の働きは、左右方向への重心移動を制動する能力低下を反映するものと考えられた。若年群では重心動揺測定値とステップ比に高い相関が認められたが、高齢群では認められなかった。これは、開眼片脚起立バランスの低下した高齢者においては、FL動作の後脚が推進力を発生よりも動作時の重心の制動に機能することを示唆していると考えられた。Rear leg during forward lunge exercise bears promotion of movement of center of gravity forward and braking of rear movement. This time, in the elderly persons, we measure the angle of the joint and postural sway of the rear leg. It aimed to clarify the balance function of the rear leg for the relation to the FL exercise in the elderly persons. Elderly group\u27s postural sway to the right and left was especially large, and the floor reaction force increased the force of the right and left direction than young group in the right and left. The characteristic of rear leg during forward lunge exercise in the elderly persons was thought that the braking disability of the postural sway to the right and left was reflected. Moreover, there was a high correlation between compared with a part of postural sway measurements and the step ratio in a young group. However, such a relation was not in the elderly group. In the elderly persons who decreases the resting upright positioning balance, it was suggested that the function of the rear leg of FL exercise in the elderly persons acted on braking of the center of gravity rather than generating the impellent

Hitomi (ASTRO-H) X-ray Astronomy Satellite

The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E  >  2  keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month

Hitomi X-Ray Studies of Giant Radio Pulses from the Crab Pulsar

To search for giant X-ray pulses correlated with the giant radio pulses (GRPs) from the Crab pulsar, we performed a simultaneous observation of the Crab pulsar with the X-ray satellite Hitomi in the 2300 keV band and the Kashima NICT radio telescope in the 1.41.7 GHz band with a net exposure of about 2 ks on 2016 March 25, just before the loss of the Hitomi mission. The timing performance of the Hitomi instruments was confirmed to meet the timing requirement and about 1000 and 100 GRPs were simultaneously observed at the main pulse and inter-pulse phases, respectively, and we found no apparent correlation between the giant radio pulses and the X-ray emission in either the main pulse or inter-pulse phase. All variations are within the 2 fluctuations of the X-ray fluxes at the pulse peaks, and the 3 upper limits of variations of main pulse or inter-pulse GRPs are 22% or 80% of the peak flux in a 0.20 phase width, respectively, in the 2300 keV band. The values for main pulse or inter-pulse GRPs become 25% or 110%, respectively, when the phase width is restricted to the 0.03 phase. Among the upper limits from the Hitomi satellite, those in the 4.510 keV and 70300 keV bands are obtained for the first time, and those in other bands are consistent with previous reports. Numerically, the upper limits of the main pulse and inter-pulse GRPs in the 0.20 phase width are about (2.4 and 9.3) 10(exp 11) erg cm(exp 2), respectively. No significant variability in pulse profiles implies that the GRPs originated from a local place within the magnetosphere. Although the number of photon-emitting particles should temporarily increase to account for the brightening of the radio emission, the results do not statistically rule out variations correlated with the GRPs, because the possible X-ray enhancement may appear due to a >0.02% brightening of the pulse-peak flux under such conditions

足指把持力とバランス能力との関係性の検討

本研究の目的は、足指把持力とバランス能力との関係性を検討することである. 対象は、健常な中高年女性13名(年齢59.8±4.3歳)と若年女性11名(年齢22.5±1.9歳)とした. 対象者には、足指把持力と立位での足圧中心(COP)の総軌跡長を測定した. COPの総軌跡長の測定は、条件の異なる2つの立位にて実施した. また、足指が床に接地した状態と接地していない状態とでFunctional Reach Test(FRT)を実施した. その結果、中高年女性と若年女性ともに、足指把持力と立位でのCOPの総軌跡長との間には相関関係が認められなかった. また、FRTの測定値は足指の接地の有無による影響が認められなかった. これらのことから、健常な中高年女性および若年女性において、足指把持力とバランス能力との明らかな関係性を示すことはできなかった.The objective of this study was to investigate the relationship between toe gripping force and balance ability. Subjects were 11 healthy young females (aged 22.5±1.9years) and 13 healthy upper-middle-aged females (aged 59.8±4.3years). Toe gripping force and the overall path length of the center of foot pressure (COP) while standing were measured. Measurement of the overall path length of COP was performed in two standing positions under two sets of conditions. In addition, the functional reach test (FRT) was administered with toes in contact with or not in contact with the floor. Results revealed no correlation between toe gripping force and overall COP path length while standing in both the upper-middle-aged group and the young group. In addition, no effect of contact or non-contact of the toes with the floor was noted in the measured FRT values. These findings showed no clear relationship between toe gripping force and balance ability in healthy young females or healthy upper-middle-aged females

高校吹奏楽部所属学生の楽器練習における身体症状の発生状況 : 演奏楽器別での症状特性について

高校吹奏楽部所属の1～3年生160名に、楽器の練習が影響していると考えられる身体症状についてアンケート調査を実施した. 結果は、チューバ奏者の多くが腰痛を訴えていた. サックス奏者やチューバ奏者には顎関節の痛みが発生していた. サックス奏者やチューバ奏者ならびにパーカッション奏者では利き手側の手関節や手指関節に関節痛が集中していた. また、整形外科的症状以外にも、頭痛、めまい、過呼吸、耳なり、倦怠感などの内科的症状が多くの学生に発生していた. これらの症状が改善できないまま学生は練習を継続していることもわかり、予防や対処法を検討していく必要があると考える.I carried out questionary survey about the physical symptom that it was thought that the exercise of the musical instrument influenced 160 1-3 year students of the high school brass band club position. Most of tubists appealed to the result for low back pain. To a saxophone player and a tubist, the pain of the temporomandibular joint occurred. In a saxophone player and a tubist and the percussion players, arthralgia concentrated on a wrist and finger joint of the handedness side. In addition, as well as an orthopedic symptom, medical symptoms such as a headache, dizziness, hyperpnoea, ringing in the ears, the lassitude occurred to many students. The student practices being able to improve these symptoms and thinks that it is necessary to examine the prevention and actions to be taken

足指把持力とバランス能力との関係性の検討

本研究の目的は、足指把持力とバランス能力との関係性を検討することである. 対象は、健常な中高年女性13名(年齢59.8±4.3歳)と若年女性11名(年齢22.5±1.9歳)とした. 対象者には、足指把持力と立位での足圧中心(COP)の総軌跡長を測定した. COPの総軌跡長の測定は、条件の異なる2つの立位にて実施した. また、足指が床に接地した状態と接地していない状態とでFunctional Reach Test(FRT)を実施した. その結果、中高年女性と若年女性ともに、足指把持力と立位でのCOPの総軌跡長との間には相関関係が認められなかった. また、FRTの測定値は足指の接地の有無による影響が認められなかった. これらのことから、健常な中高年女性および若年女性において、足指把持力とバランス能力との明らかな関係性を示すことはできなかった.The objective of this study was to investigate the relationship between toe gripping force and balance ability. Subjects were 11 healthy young females (aged 22.5±1.9years) and 13 healthy upper-middle-aged females (aged 59.8±4.3years). Toe gripping force and the overall path length of the center of foot pressure (COP) while standing were measured. Measurement of the overall path length of COP was performed in two standing positions under two sets of conditions. In addition, the functional reach test (FRT) was administered with toes in contact with or not in contact with the floor. Results revealed no correlation between toe gripping force and overall COP path length while standing in both the upper-middle-aged group and the young group. In addition, no effect of contact or non-contact of the toes with the floor was noted in the measured FRT values. These findings showed no clear relationship between toe gripping force and balance ability in healthy young females or healthy upper-middle-aged females