Spectral transitions of an ultraluminous X-ray source, NGC 2403 Source 3

Suzaku observation of an ultraluminous X-ray source, NGC 2403 Source 3, performed on 2006 March 16--17, is reported. The Suzaku XIS spectrum of Source 3 was described with a multi-color black-body-like emission from an optically thick accretion disk. The innermost temperature and radius of the accretion disk was measured to be $T_{\rm in} = 1.08_{-0.03}^{+0.02}$ keV and $R_{\rm in} = 122.1_{-6.8}^{+7.7} \alpha^{1/2}$ km, respectively, where $\alpha = (\cos 60^\circ /\cos i)$ with $i$ being the disk inclination. The bolometric luminosity of the source was estimated to be $L_{\rm bol} = 1.82 \times 10^{39} \alpha$ ergs s$^{-1}$. Archival Chandra and XMM-Newton data of the source were analyzed for long-term spectral variations. In almost all observations, the source showed multi-color black-body-like X-ray spectra with parameters similar to those in the Suzaku observation. In only one Chandra observation, however, Source 3 was found to exhibit a power-law-like spectrum, with a photon index of $\Gamma = 2.37 \pm 0.08$, when it was fainter by about $\sim 15$ than in the Suzaku observation. The spectral behavior is naturally explained in terms of a transition between the slim disk state and the "very high" states, both found in Galactic black hole binaries when their luminosity approach the Eddington limit. These results are utilized to argue that ultraluminous X-ray sources generally have significantly higher black-hole masses than ordinary stellar-mass black holes.Comment: Accepted for PASJ 3nd Suzaku special issu

EEG resting-state networks in Alzheimer’s disease associated with clinical symptoms

Alzheimer’s disease (AD) is a progressive neuropsychiatric disease affecting many elderly people and is characterized by progressive cognitive impairment of memory, visuospatial, and executive functions. As the elderly population is growing, the number of AD patients is increasing considerably. There is currently growing interest in determining AD’s cognitive dysfunction markers. We used exact low-resolution-brain-electromagnetic-tomography independent-component-analysis (eLORETA-ICA) to assess activities of five electroencephalography resting-state-networks (EEG-RSNs) in 90 drug-free AD patients and 11 drug-free patients with mild-cognitive-impairment due to AD (ADMCI). Compared to 147 healthy subjects, the AD/ADMCI patients showed significantly decreased activities in the memory network and occipital alpha activity, where the age difference between the AD/ADMCI and healthy groups was corrected by linear regression analysis. Furthermore, the age-corrected EEG-RSN activities showed correlations with cognitive function test scores in AD/ADMCI. In particular, decreased memory network activity showed correlations with worse total cognitive scores for both Mini-Mental-State-Examination (MMSE) and Alzheimer’s Disease-Assessment-Scale-cognitive-component-Japanese version (ADAS-J cog) including worse sub-scores for orientation, registration, repetition, word recognition and ideational praxis. Our results indicate that AD affects specific EEG-RSNs and deteriorated network activity causes symptoms. Overall, eLORETA-ICA is a useful, non-invasive tool for assessing EEG-functional-network activities and provides better understanding of the neurophysiological mechanisms underlying the disease

MtDNA variation and human-mediated introgression of indigenous sus populations on several Indonesian Islands

o examine the genetic origin of the domestic pig, the distribution of wild boar, and　human-mediated translocation of the domestic pig, we collected 223 samples from domestic pigs and　wild boars from eight Indonesian islands, sequenced the control region of mitochondrial DNA　(mtDNA) from each sample, and compared these sequences with previously determined sequences from East and Southeast Asian domestic pigs and wild boars. Three Sus species (S. scrofa, S.verrucosus, and S. celebensis) were identified on the Indonesian islands. The mtDNA sequences of　three Indonesian Sus species were diverse, and they clustered into three lineages with low bootstrap　values (an S. scrofa group including East and Southeast Asian domestic pigs and wild boars, a group including indigenous S. scrofa together with S. verrucosus from Sumatra and Java Islands, and an S.celebensis group from Sulawesi Island). The mtDNA haplotypes of S. scrofa wild boars from three　(Sumbawa, Flores and New Guinea) islands and domestic pigs from two (Lombok and Timor) islands east of the Wallace Line, and some S. scrofa wild boars from Sumatra and Java Islands were related　to Vietnamese pig mtDNA sequences in the East and Southeast Asian domestic pig and wild boar　clade, supporting that ancient immigrants likely introduced domestic pigs from the Asian continent to east Indonesian islands. The mtDNA haplotypes of S. celebensis were broadly divided into three　groups, which were distributed in the north and southwest areas, central area and southeast area of　Sulawesi Island

Indices calculated by serum creatinine and cystatin C as predictors of liver damage, muscle strength and sarcopenia in liver disease

Serum creatinine (Cr)-based glomerular filtration rate (CrGFR) is overestimated in liver disease. The present study evaluated whether the difference in CrGFR and cystatin C (CysC) GFR (dGFR) is significant in liver disease. The Cr-to-CysC ratio and sarcopenia index (SI) have been reported to correlate with muscle volume. An estimated total body muscle mass with Cr, CysC and calculated body muscle mass (CBMM) has also been reported to correlate with muscle mass. The applicability of dGFR, SI and CBMM for liver disease were evaluated. A total of 313 patients with liver damage were evaluated for Child-Pugh score, albumin-bilirubin (ALBI) score, model for end-stage liver disease, fibrosis-4, Cr, CysC, Cr-based estimated GFR (CreGFR), CysCGFR and grip strength. Of the 313 patients, 199 were evaluated using cross-sectional computed tomography (CT) of the third lumbar vertebra to determine the skeletal muscle (SM) mass. dGFR, CBMM and SI were compared to liver damage, muscle strength and muscle mass. In the 313 patients, dGFR was correlated with age, ALBI and grip strength; CBMM was correlated with body mass index (BMI) and grip strength; and SI was correlated with BMI and grip strength. In patients evaluated with CT, the correlation coefficients for CBMM and SI with SM were 0.804 and 0.293, respectively. Thus, CBMM and SI were associated with sarcopenia. The relationship between dGFR and ALBI does not differ with different grades of CrGFR-based chronic kidney disease (CKD). dGFR is a marker of liver damage and muscle strength regardless of CKD. CBMM and SI are markers for sarcopenia in liver disease

In Orbit Timing Calibration of the Hard X-Ray Detector on Board Suzaku

The hard X-ray detector (HXD) on board the X-ray satellite Suzaku is designed to have a good timing capability with a 61 $\mu$s time resolution. In addition to detailed descriptions of the HXD timing system, results of in-orbit timing calibration and performance of the HXD are summarized. The relative accuracy of time measurements of the HXD event was confirmed to have an accuracy of $1.9\times 10^{-9}$ s s$^{-1}$ per day, and the absolute timing was confirmed to be accurate to 360 $\mu$s or better. The results were achieved mainly through observations of the Crab pulsar, including simultaneous ones with RXTE, INTEGRAL, and Swift.Comment: Accepted for publication on PASJ Vol.60, SP-1, 200

JASMINE: Near-infrared astrometry and time-series photometry science

The Japan Astrometry Satellite Mission for INfrared Exploration (JASMINE) is a planned M-class science space mission by the Institute of Space and Astronautical Science, the Japan Aerospace Exploration Agency. JASMINE has two main science goals. One is Galactic archaeology with a Galactic Center survey, which aims to reveal the Milky Way’s central core structure and formation history from Gaia-level (∼25 ${\mu}$as) astrometry in the near-infrared (NIR) Hw band (1.0–1.6 ${\mu}$m). The other is an exoplanet survey, which aims to discover transiting Earth-like exoplanets in the habitable zone from NIR time-series photometry of M dwarfs when the Galactic Center is not accessible. We introduce the mission, review many science objectives, and present the instrument concept. JASMINE will be the first dedicated NIR astrometry space mission and provide precise astrometric information on the stars in the Galactic Center, taking advantage of the significantly lower extinction in the NIR. The precise astrometry is obtained by taking many short-exposure images. Hence, the JASMINE Galactic Center survey data will be valuable for studies of exoplanet transits, asteroseismology, variable stars, and microlensing studies, including discovery of (intermediate-mass) black holes. We highlight a swath of such potential science, and also describe synergies with other missions

The goal of Japan Search Action Plan 2021-2025: Feedback from partner institutions in the development process of the Action Plan.

In September 2021, the Digital Archive Japan Promotion Committee and the Practitioner Review Committee (Secretariat of Cabinet Office) formulated the "Japan Search Strategy 2021-2025," which outlines the direction of Japan Search's activities in the future. And the "Japan Search Action Plan 2021-2025" was formulated to realize the goals of this strategy in April of the following year. The National Diet Library, based on the position of those in charge of system development and operation as well as collaborative practices of Japan Search, prepared the draft of Action Plan. In process of making the draft, the National Diet Library planned to hold two rounds of discussions with Japan Search partners to exchange opinions. This presentation will introduce the main opinions from the partner organizations that emerged from the discussions and explain what the Action Plan aims to achieve.</p