Measuring the Broad-band X-Ray Spectrum from 400 eV to 40 keV in the Southwest Part of the Supernova Remnant RX J1713.7-3946

We report on results from Suzaku broadband X-ray observations of the southwest part of the Galactic supernova remnant (SNR) RX J1713.7-3946 with an energy coverage of 0.4-40 keV. The X-ray spectrum, presumably of synchrotron origin, is known to be completely lineless, making this SNR ideally suited for a detailed study of the X-ray spectral shape formed through efficient particle acceleration at high speed shocks. With a sensitive hard X-ray measurement from the HXD PIN on board Suzaku, we determine the hard X-ray spectrum in the 12--40 keV range to be described by a power law with photon index Gamma = 3.2+/- 0.2, significantly steeper than the soft X-ray index of Gamma = 2.4+/- 0.05 measured previously with ASCA and other missions. We find that a simple power law fails to describe the full spectral range of 0.4-40 keV and instead a power-law with an exponential cutoff with hard index Gamma = 1.50+/- 0.09 and high-energy cutoff epsilon_c = 1.2+/- 0.3 keV formally provides an excellent fit over the full bandpass. If we use the so-called SRCUT model, as an alternative model, it gives the best-fit rolloff energy of epsilon_{roll} = 0.95+/- 0.04 keV. Together with the TeV gamma-ray spectrum ranging from 0.3 to 100 TeV obtained recently by HESS observations, our Suzaku observations of RX J1713.7-3946 provide stringent constraints on the highest energy particles accelerated in a supernova shock.Comment: 11 pages, 11 figures, accepted for publication in Publications of the Astronomical Society of Japan (PASJ

The efficacy and safety of additional administration of tacrolimus in patients with rheumatoid arthritis who showed an inadequate response to tocilizumab

Objectives: Tocilizumab (TCZ) shows good retention in patients with rheumatoid arthritis (RA), but no previous reports demonstrated hopeful treatment options against inadequate response to TCZ. Tacrolimus (TAC) has proved to show efficacy against inadequate response to tumor necrosis factor alpha inhibitors, yet its add-on effects on TCZ remain unknown. Methods: Twenty patients with RA (17 women, age 58.6 years, disease duration 12.1 years, prior TCZ duration 2.6 years, 18 intravenous [8 mg/kg/month] and 2 subcutaneous [324 mg/month] TCZ treatments, methotrexate 6.1 mg/week [70.0%]) who showed an inadequate response to TCZ (clinical disease activity index [CDAI] ≥ 5.8, 18 secondary non-responders) were additionally treated with TAC (1.1 mg/day), and enrolled in this 24-week, prospective study. Results: Seventeen patients (85.0%) continued the treatment for 24 weeks. Statistically significant decreases in outcome measures were as follows: disease activity score based on 28 joints with C-reactive protein (DAS28-CRP) from 3.3 at baseline to 2.1 at week 24 (p < 0.001), CDAI from 17.7 to 7.6 (p < 0.001), and serum matrix metalloproteinase-3 levels from 232.8 to 66.2 ng/ml (p < 0.001). About 15 patients (75%) achieved low disease activity or remission (DAS28-CRP ≤2.7 or CDAI ≤10) at week 24. Conclusions: Adding low-dose TAC to inadequate responders to TCZ may be a promising complementary treatment option.Kaneshiro S., Ebina K., Hirao M., et al. The efficacy and safety of additional administration of tacrolimus in patients with rheumatoid arthritis who showed an inadequate response to tocilizumab. Modern Rheumatology 27, 42 (2017); https://doi.org/10.1080/14397595.2016.1181315

Impact of combining medial capsule interposition with modified scarf osteotomy for hallux valgus

Objectives: To clarify the effect of combining medial capsule interposition with modified scarf osteotomy for hallux valgus. Methods: A multicenter, retrospective study included 64 cases [59 osteoarthritis patients (excluding rheumatoid arthritis); age 68.8 years, range 40–93 years] of modified scarf osteotomy which were performed from 2013 to 2017 and followed for 26.6 (range, 13–50) months. Patients were treated by either (1) without medial capsule interposition (33 cases) or (2) combined with interposition (31 cases) at each senior surgeon’s discretion. The Japanese Society for Surgery of the Foot (JSSF) hallux metatarsophalangeal (MTP)-interphalangeal scale was evaluated along with radiographic parameters (hallux valgus angle [HVA], first and second metatarsals intermetatarsal angles, and Hardy grade). Results: All JSSF scale and radiographic parameters were similar at baseline and significantly improved at final follow-up in both groups (pre-operation vs. final follow-up: p <.001). However, compared to without interposition group, interposition group showed significantly higher improvement in the JSSF scale (pre-operation to final follow-up: p value between the two groups at final follow-up) for pain (without interposition: 19.4–34.2, interposition: 18.4–37.1; p =.02), function (without interposition: 20.8–33.6, interposition: 18.3–36.6; p =.005), total score (without interposition: 41.5–81.8, interposition: 38.5–88.5; p <.001), and the MTP joint space (without interposition: 1.4–1.5 mm, interposition: 1.6–2.6 mm; p <.001) with significant correlation between the total JSSF score (r =.40; p =.001). Conclusion: Combining medial capsule interposition with modified scarf osteotomy significantly improved mid-term clinical outcomes.Ebina K., Hirao M., Tsuboi H., et al. Impact of combining medial capsule interposition with modified scarf osteotomy for hallux valgus. Modern Rheumatology 30, 204 (2020); https://doi.org/10.1080/14397595.2019.1572261

The ASTRO-H X-ray Observatory

The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions initiated by the Institute of Space and Astronautical Science (ISAS). ASTRO-H will investigate the physics of the high-energy universe via a suite of four instruments, covering a very wide energy range, from 0.3 keV to 600 keV. These instruments include a high-resolution, high-throughput spectrometer sensitive over 0.3-2 keV with high spectral resolution of Delta E < 7 eV, enabled by a micro-calorimeter array located in the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers covering 5-80 keV, located in the focal plane of multilayer-coated, focusing hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12 keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the 40-600 keV band. The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes.Comment: 22 pages, 17 figures, Proceedings of the SPIE Astronomical Instrumentation "Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray

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

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