131 research outputs found
霊芝菌糸体培養基熱水抽出物(MAK)由来PolysaccharidesはマクロファージからGM-CSFを誘導しマウスインドメサシン小腸炎を改善する
広島大学(Hiroshima University)博士(医学)Doctor of Philosophy in Medical Sciencedoctora
Very Long Baseline Array Imaging of Parsec-scale Radio Emissions in Nearby Radio-quiet Narrow-line Seyfert 1 Galaxies
We conducted Very Long Baseline Array (VLBA) observations of seven nearby
narrow-line Seyfert 1 (NLS1) galaxies at 1.7 GHz (18cm) with milli-arcsecond
resolution. This is the first systematic very long baseline interferometry
(VLBI) study focusing on the central parsec-scale regions of radio-quiet NLS1s.
Five of the seven were detected at a brightness temperature of >~5x10^6 K and
contain radio cores with high brightness temperatures of >6x10^7 K, indicating
a nonthermal process driven by jet-producing central engines as is observed in
radio-loud NLS1s and other active galactic nucleus (AGN) classes. VLBA images
of MRK 1239, MRK 705, and MRK 766 exhibit parsec-scale jets with clear linear
structures. A large portion of the radio power comes from diffuse emission
components that are distributed within the nuclear regions (<~300 pc), which is
a common characteristic throughout the observed NLS1s. Jet kinetic powers
limited by the Eddington limit may be insufficient to allow the jets escape to
kiloparsec scales for these radio-quiet NLS1s with low-mass black holes of
<~10^7 M_sun.Comment: 12 pages, 3 figures, 3 tables, accepted for publication in Ap
VLBI Monitoring of 3C 84 (NGC 1275) in Early Phase of the 2005 Outburst
Multi-epoch Very Long Baseline Interferometry (VLBI) study of the sub-pc
scale jet of 3C 84 is presented. We carried out 14-epoch VLBI observations
during 2006-2009 with the Japanese VLBI Network (JVN) and the VLBI Exploration
of Radio Astrometry (VERA), immediately following the radio outburst that began
in 2005. We confirmed that the outburst was associated with the central ~1 pc
core, accompanying the emergence of a new component. This is striking evidence
of the recurrence of jet activity. The new component became brighter during
2008, in contrast to the constant gamma-ray emission that was observed with the
Fermi Gamma-ray Space Telescope during the same time. We found that the
projected speed of the new component is 0.23c from 2007/297 (2007 October 24)
to 2009/114 (2009 April 24). The direction of movement of this component
differs from that of the pre-existing component by ~40 degree. This is the
first measurement of kinematics of a sub-pc jet in a gamma-ray active phase.
Possible detection of jet deceleration and the jet kinematics in connection
with the gamma-ray emission is discussed.Comment: 5 pages, 3 figures. Accepted for publication in PAS
Intestinal Tuberculosis with Hoarseness as a Chief Complaint due to Mediastinal Lymphadenitis
A 68-year-old woman was admitted to our hospital complaining of hoarseness. A chest X-ray detected an abnormal shadow on the upper right lung. Bronchoscopic examination revealed that the left vocal cord was fixed in the paramedian position, and therefore left recurrent nerve paralysis was suspected. Lymphadenopathy was found in the left supraclavicular area. Chest computed tomography showed that the pretracheal and subaortic lymph nodes were swollen. Gastroendoscopy showed a 2-cm protruding lesion with ulceration on the upper esophagus. Histological examination of the supraclavicular lymph nodes and biopsy specimens from the esophagus revealed non-specific inflammation. PET-CT showed abnormal accumulations not only on the upper right lung but also on the lower right of the abdomen. Colonoscopy was performed and multiple erosions on the terminal ileum were found. Polymerase chain reaction analysis of a specimen biopsied from the erosion of the terminal ileum was positive for Mycobacterium tuberculosis and intestinal tuberculosis was diagnosed. The patient was then treated with anti-tuberculous therapy. After treatment, the erosions on the terminal ileum, the swelling of the mediastinal lymphadenopathy, and the esophageal ulcer were all improved. The hoarseness was subsequently relieved. This is the first report of intestinal tuberculosis with hoarseness as a chief complaint due to mediastinal lymphadenitis
Auto-Luminescent Genetically-Encoded Ratiometric Indicator for Real-Time Ca2+ Imaging at the Single Cell Level
Background: Efficient bioluminescence resonance energy transfer (BRET) from a bioluminescent protein to a fluorescent protein with high fluorescent quantum yield has been utilized to enhance luminescence intensity, allowing single-cell imaging in near real time without external light illumination. Methodology/Principal Findings: We applied BRET to develop an autoluminescent Ca2+ indicator, BRAC, which is composed of Ca^[2+]-binding protein, calmodulin, and its target peptide, M13, sandwiched between a yellow fluorescent protein variant, Venus, and an enhanced Renilla luciferase, RLuc8. Adjusting the relative dipole orientation of the luminescent protein's chromophores improved the dynamic range of BRET signal change in BRAC up to 60%, which is the largest dynamic range among BRET-based indicators reported so far. Using BRAC, we demonstrated successful visualization of Ca2+ dynamics at the single-cell level with temporal resolution at 1 Hz. Moreover, BRAC signals were acquired by ratiometric imaging capable of canceling out Ca^[2+]-independent signal drifts due to change in cell shape, focus shift, etc. Conclusions/Significance: The brightness and large dynamic range of BRAC should facilitate high-sensitive Ca2+ imaging not only in single live cells but also in small living subjects
Multifrequency VLBI Observations of the Broad Absorption Line Quasar J1020+4320: Recently Restarted Jet Activity?
This paper reports very-long-baseline interferometry observations of the
radio-loud broad absorption line (BAL) quasar J1020+4320 at 1.7, 2.3, 6.7, and
8.4 GHz using the Japanese VLBI network (JVN) and European VLBI network (EVN).
The radio morphology is compact with a size of ~10 pc. The convex radio
spectrum is stable over the last decade; an observed peak frequency of 3.2 GHz
is equivalent to 9.5 GHz in the rest frame, suggesting an age of the order of
~100 years as a radio source, according to an observed correlation between
linear size and peak frequency of compact steep spectrum (CSS) and giga-hertz
peaked spectrum (GPS) radio sources. A low-frequency radio excess suggests
relic of past jet activity. J1020+4320 may be one of the quasars with recurrent
and short-lived jet activity during a BAL-outflowing phase.Comment: 7 pages, 2 figures, 2 tables, accepted for publication in PAS
Influence of gas environment and heating on atomic structures of platinum nanoparticle catalysts for proton-exchange membrane fuel cells
Atomic-scale relaxations of platinum nanoparticles (Pt NPs) for fuel-cell catalysts are evaluated by spherical-aberration corrected environmental transmission electron microscopy (ETEM) under reference high-vacuum and N2 atmospheres, and then under reactive H2, CO and O2 atmospheres, combined with ex situ durability test using an electrochemical half-cell. In high-vacuum, increasing roughness due to continuous relaxation of surface-adsorbed Pt atoms is quantified in real-space. Under H2 and N2 atmospheres at a critical partial pressure of 1 × 10-2 Pa the stability of the surface facets is for the first time found to be improved. The adsorption behaviour of CO molecules is investigated using experimentally measured Pt-Pt bond lengths on the topmost surface layer of Pt NPs. The deactivation of Pt NPs in the anode environment of a proton-exchange-membrane fuel-cell is demonstrated at the atomic-scale in the ETEM, and the transformation of NPs into disordered nanoclusters is systematically quantified using the partial size distribution of Pt atomic clusters under controlled heating experiments at 423, 573 and 723 K
Japanese VLBI Network observations of radio-loud narrow-line Seyfert 1 galaxies
We performed phase-reference very long baseline interferometry (VLBI)
observations on five radio-loud narrow-line Seyfert 1 galaxies (NLS1s) at 8.4
GHz with the Japanese VLBI Network (JVN). Each of the five targets (RXS
J08066+7248, RXS J16290+4007, RXS J16333+4718, RXS J16446+2619, and B3
1702+457) in milli-Jansky levels were detected and unresolved in
milli-arcsecond resolutions, i.e., with brightness temperatures higher than
10^7 K. The nonthermal processes of active galactic nuclei (AGN) activity,
rather than starbursts, are predominantly responsible for the radio emissions
from these NLS1s. Out of the nine known radio-loud NLS1s, including the ones
chosen for this study, we found that the four most radio-loud objects
exclusively have inverted spectra. This suggests a possibility that these NLS1s
are radio-loud due to Doppler beaming, which can apparently enhance both the
radio power and the spectral frequency.Comment: 8 pages, 2 figures, accepted for publication in PAS
Experimental inspection of a computationally-designed NiCrMnSi Heusler alloy with high Curie temperature
Nowadays advanced magnetic tunnel junction applications demand very high tunnel magnetoresistance at room temperature, thus it is quite important to explore high Curie temperature Tc half-metallic Heusler alloys. In this article rst-principles calculation unveiled that NiCrMnSi has Tc of 1200 K comparable to that of the traditional Co2MnSi Heusler alloys, even though it does not contain Co element. In addition, we examined whether NiCrMnSi Heulser phase lms can be obtained by a magnetron sputtering on MgO substrates. The results of the structural analysis and rst-principles calculations indicated that NiCrMnSi Heusler phase is metastable. A possible route to obtain metastable NiCrMnSi Heusler alloy is to utilize appropriate templates
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