Search

To reveal the infrared absorption causes in the wavelength region between electronic and lattice absorptions, we measured the temperature dependence of the absorption coefficient of $p$-type low-resistivity ($\sim 10^2~{\rm \Omega cm}$) CdZnTe crystals. We measured the absorption coefficients of CdZnTe crystals in four-wavelength bands ($\lambda=6.45$, 10.6, 11.6, 15.1$~\mu$m) over the temperature range of $T=8.6-300$ K with an originally developed system. The CdZnTe absorption coefficient was measured to be $\alpha=0.3-0.5$ ${\rm cm^{-1}}$ at $T=300$ K and $\alpha=0.4-0.9$ ${\rm cm^{-1}}$ at $T=8.6$ K in the investigated wavelength range. With an absorption model based on transitions of free holes and holes trapped at an acceptor level, we conclude that the absorption due to free holes at $T=150-300$ K and that due to trapped-holes at $T, Comment: Accepted for publication in Journal of Electronic Material, 30 pages, 6 figures, 5 tables

Here we examined the effect of nicotine on angiogenesis in the brain after intracerebral hemorrhage (ICH), as angiogenesis is considered to provide beneficial effects on brain tissues during recovery from injury after stroke. Nicotine was administered to C57BL/6 mice suffering from collagenase-induced ICH in the striatum, either by inclusion in drinking water or by daily intraperitoneal injection. Nicotine administration by both routes enhanced angiogenesis within the hematoma-affected regions, as revealed by increased CD31-immunopositive area at 7 and 14 d after ICH. Double immunofluorescence histochemistry against CD31 and proliferating cell nuclear antigen revealed that nicotine increased the number of newly generated vascular endothelial cells within the hematoma. In spite of enhanced angiogenesis, nicotine did not worsen vascular permeability after ICH, as assessed by Evans Blue extravasation. These effects of nicotine were accompanied by an increased number of surviving neurons in the hematoma at 7 d after ICH. Unexpectedly, nicotine did not increase expression of vascular endothelial growth factor mRNA in the brain and did not enhance recruitment of endothelial progenitor cells from the bone marrow. These results suggest that nicotine enhances angiogenesis in the brain after ICH, via mechanisms distinct from those involved in its action on angiogenesis in peripheral tissues.

A recent hydrodynamic model, "radiation-driven fountain model" (Wada et al. 2016), presented a dynamical picture that active galactic nuclei (AGNs) tori sustain their geometrical thickness by gas circulation around AGNs, and previous papers confirmed that this picture is consistent with multi-wavelength observations of nearby Seyfert galaxies. Recent near-infrared observations implied that CO rovibrational absorption lines ($\Delta J=\pm1$, $v=0-1$, $\lambda \sim 4.7$ $\mathrm{\mu m}$) could probe physical properties of the inside tori. However, the origin of the CO absorption lines has been under debate. In this paper, we investigate the origin of the absorption lines and conditions for detecting them by performing line radiative transfer calculations based on the radiation-driven fountain model. We find that CO rovibrational absorption lines are detected at inclination angles $\theta_\mathrm{obs} = 50-80$ $^{\circ}$. At the inclination angle $\theta_\mathrm{obs} = 77$ $^{\circ}$, we observe multi-velocity components: inflow ($v_\mathrm{LOS}=30$ $\mathrm{kms^{-1}}$), systemic ($v_\mathrm{LOS}=0 \, \mathrm{kms^{-1}}$), and outflows ($v_\mathrm{LOS}=-75,\, -95,$ and $-105$ $\mathrm{kms^{-1}}$). The inflow and outflow components ($v_\mathrm{LOS}= 30$ and $-95$ $\mathrm{kms^{-1}}$) are collisionally excited at the excitation temperature of $186$ and $380$ K up to $J=12$ and $4$, respectively. The inflow and outflow components originate from the accreting gas on the equatorial plane at $1.5$ pc from the AGN center and the outflowing gas driven by AGN radiation pressure at $1.0$ pc, respectively. These results suggest that CO rovibrational absorption lines can provide us with the velocities and kinetic temperatures of the inflow and outflow in the inner a-few-pc regions of AGN tori, and the observations can probe the gas circulation inside the tori., Comment: 19 pages, 17 figures, 3 tables, accepted by The Astrophysical Journal

Context: The Monte Carlo method is probably the most widely used approach to solve the radiative transfer problem, especially in a general 3D geometry. The physical processes of emission, absorption, and scattering are easily incorporated in the Monte Carlo framework. Net stimulated emission, or absorption with a negative cross section, does not fit this method, however. Aims: We explore alterations to the standard photon packet life cycle in Monte Carlo radiative transfer that allow the treatment of net stimulated emission without loss of generality or efficiency. Methods: We present the explicit absorption technique that allows net stimulated emission to be handled efficiently. It uses the scattering rather than the extinction optical depth along a photon packet's path to randomly select the next interaction location, and offers a separate, deterministic treatment of absorption. We implemented the technique in a special-purpose Monte Carlo code for a two-stream 1D radiative transfer problem and in the fully featured 3D code SKIRT, and we studied its overall performance using quantitative statistical tests. Results: Our special-purpose code is capable of recovering the analytical solutions to the two-stream problem in all regimes, including the one of strong net stimulated emission. The implementation in SKIRT is straightforward, as the explicit absorption technique easily combines with the variance reduction and acceleration techniques already incorporated. In general, explicit absorption tends to improve the efficiency of the Monte Carlo routine in the regime of net absorption. Conclusions: Explicit absorption allows the treatment of net stimulated emission in Monte Carlo radiative transfer, it interfaces smoothly with... (abridged), Comment: 14 pages, accepted for publication in A&A

The ultraluminous infrared galaxy IRAS 17208$-$0014 is a late-stage merger that hosts a buried active galactic nucleus (AGN). To investigate its nuclear structure, we performed high spatial resolution ($\sim0.\!\!^{\prime\prime}04\sim32\,\mathrm{pc}$) Atacama Large Millimeter/submillimeter Array (ALMA) observations in Band 9 ($\sim$450\,\micron\ or $\sim$660\,GHz), along with near-infrared AKARI spectroscopy in 2.5--5.0\,\micron. The Band 9 dust continuum peaks at the AGN location, and toward this position CO($J$=6--5) and CS($J$=14--13) are detected in absorption. Comparison with non-local thermal equilibrium calculations indicates that, within the central beam ($r\sim20\,\mathrm{pc}$), there exists a concentrated component that is dense ($10^7\,\mathrm{cm}^{-2}$) and warm ($>$200\,K) and has a large column density ($N_\mathrm{H_2}>10^{23}\,\mathrm{cm}^{-2}$). The AKARI spectrum shows deep and broad CO ro-vibrational absorption at 4.67\,\micron. Its band profile is well reproduced with a similarly dense and large column but hotter ($\sim$1000\,K) gas. The region observed through absorption in the near-infrared is highly likely in the nuclear direction, as in the sub-millimeter, but with a narrower beam including a region closer to the nucleus. The central component is considered to possess a hot structure where vibrationally excited HCN emission originates. The most plausible heating source for the gas is X-rays from the AGN. The AKARI spectrum does not show other AGN signs in 2.5--4\,\micron, but this absence may be usual for AGNs buried in a hot mid-infrared core. Besides, based on our ALMA observations, we relate various nuclear structures of IRAS 17208$-$0014 that have been proposed in the literature., 28 pages, 16 figures, accepted for publication in ApJ

Inflammatory responses are considered to play pivotal roles in the pathogenesis of intracerebral hemorrhage (ICH). Here we show that a nuclear receptor Nurr1 (NR4A2) was expressed prominently in microglia/macrophages and astrocytes in the perihematomal region in the striatum of mice after ICH. Daily administration of a Nurr1 agonist amodiaquine (40 mg/kg, i.p.) from 3 h after ICH induction diminished perihematomal activation of microglia/macrophages and astrocytes. Amodiaquine also suppressed ICH-induced mRNA expression of IL-1β, CCL2 and CXCL2, and ameliorated motor dysfunction of mice. These results suggest that Nurr1 serves a novel target for ICH therapy.

We studied the absorption features of CO lines against the continuum originating from the heated dust in the obscuring tori around active galactic nuclei (AGNs). We investigated the formation of absorption lines corresponding to the CO rotational transitions using three-dimensional non-LTE line transfer simulations considering the dust thermal emission. As in Papers I--III of this series, we performed post-processed radiative transfer calculations using the "radiation-driven fountain model" (wada2016}, which yields a geometrically thick obscuring structure around the nucleus. This model is consistent with the spectral energy distribution of the nearest type-2 Seyfert galaxy, the Circinus galaxy. We found that the continuum-subtracted channel maps of $J = 4-3$ and higher transitions show absorption regions along the disk mid-plane for an edge-on viewing angle. The spectra consist of multiple absorption and emission features, reflecting the internal inhomogeneous and turbulent structure of the torus. The deepest absorption feature is caused by the gas on the near-side of the torus between $r =10$ and 15 pc, which is located in front of the AGN-heated dust inside $r \simeq 5$ pc. We also found that a spatial resolution of 0.5--1.0 pc is necessary to resolve the absorption features. Moreover, the inclination angle must be close to the edge-on angle (i.e., $\sim 85^\circ$) to observe the absorption features. The findings of the present study imply that combining our radiation-hydrodynamic model with high-resolution observations of CO (7-6) by ALMA can provide new information about the internal structure of the molecular tori in nearby AGNs., Comment: 21 pages, 12 figures, accepted by Astrophysical Journal

Understanding the inner structure of the clumpy molecular torus surrounding the active galactic nucleus is essential in revealing the forming mechanism. However, spatially resolving the torus is difficult because of its size of a few parsecs. Thus, to probe the clump conditions in the torus, we performed the velocity decomposition of the CO rovibrational absorption lines ($\Delta{v}=0\to 1,\ \Delta{J}=\pm 1$) at $\lambda\sim 4.67\,\mathrm{\mu{m}}$ observed toward an ultraluminous infrared galaxy IRAS 08572+3915 NW with the high-resolution spectroscopy ($R\sim 10{,}000$) of Subaru Telescope. Consequently, we found that each transition had two outflowing components, i.e., (a) and (b), both at approximately $\sim -160\,\mathrm{km\,s^{-1}}$, but with broad and narrow widths, and an inflowing component, i.e., (c), at approximately $\sim +100\,\mathrm{km\,s^{-1}}$, which were attributed to the torus. The ratios of the velocity dispersions of each component lead to those of the rotating radii around the black hole of $R_\mathrm{rot,a}:R_\mathrm{rot,b}:R_\mathrm{rot,c}\approx 1:5:17$, indicating the torus where clumps are outflowing in the inner regions and inflowing in the outer regions if a hydrostatic disk with $\sigma_V\propto R_\mathrm{rot}^{-0.5}$ is assumed. Based on the kinetic temperature of components (a) and (b) of $\sim 720\,\mathrm{K}$ and $\sim 25\,\mathrm{K}$ estimated from the level population, the temperature gradient is $T_\mathrm{kin}\propto R_\mathrm{rot}^{-2.1}$. Magnetohydrodynamic models with large density fluctuations of two orders of magnitude or more are necessary to reproduce this gradient., Comment: Accepted for publication in ApJ, 27 pages, 13 figures, 6 tables, Minor changes after proof (v3)

We measured the transmittance of low-resistivity (∼ 10^2 Ωcm) and high-resistivity (> 10^10 Ωcm) CdZnTe, which are candidates for Immersion grating (IG) in 10–18μm wavelength, at cryogenic temperature. IG is a compact diffraction grating and we are developing a cryogenically operated 10--18μm IG for SMI/HR (SPICA Mid-Infrared Instrument / High-Resolution spectrometer) of SPICA (SPace Infrared telescope for Cosmology and Astrophysics) We performed two experiments: transmittance measurement with a convergent light Fourier transform spectrometer, and with a collimated lamp beam system. Our result shows that the low-resistivity CdZnTe has large absorption (> 0.5 cm^{−1} ) and the high-resistivity CdZnTe has low absorption (< 0.1 cm^{-1} ) at 8.5K at 10--18 μm. The high-resistivity CdZnTe is promising as an IG material although higher precision measurement is needed to determine whether it meets the absorption coefficient requirement (< 0.01 cm^{-1}) at cryogenic temperature.

SMI (SPICA Mid-infrared Instrument) is one of the three focal-plane science instruments for SPICA. SMI is the Japanese-led instrument proposed and managed by a university consortium. SMI covers the wavelength range from 10 to 36 μm with four separate channels: the low-resolution (R = 60 – 160) spectroscopy function for 17 – 36 μm, the broad-band (R = 5) imaging function at 34 μm, the mid-resolution (R = 1400 – 2600) spectroscopy function for 18 – 36 μm, and the high-resolution (R = 29000) spectroscopy function for 10 – 18 μm. In this presentation, we will show the latest design and specifications of SMI as a result of feasibility studies.

We examined the effects of compounds shown to activate aryl hydrocarbon receptor (AhR) signaling on a mouse model of intracerebral hemorrhage (ICH). Daily oral administration of laquinimod (25 mg/kg) or 3,3′-diindolylmethane (250 mg/kg) from 3 h after ICH induction improved motor functions, prevented the decrease of neurons within the hematoma, and attenuated activation of microglia/macrophages and astrocytes in the perihematomal region as well as infiltration of neutrophils into the hematoma. Elevated expression of AhR was detected in microglia and neutrophils, and both drugs inhibited upregulation of interleukin-6 and CXCL1. These results propose AhR as a therapeutic target for ICH.

Cerebrovascular disorders including ischemic stroke, intracerebral hemorrhage and subarachnoid hemorrhage are among the major clinical concerns for which effective therapies are poorly available. Accumulating lines of evidence indicate that drugs acting on nicotinic acetylcholine receptors (nAChRs) may provide therapeutic effects on these disorders, based on their neuroprotective and anti-inflammatory actions. For example, the cholinergic neurotransmission in the central nervous system via nAChRs may function as an endogenous neuroprotective system that prevents pathogenic events associated with ischemic stroke. On the other hand, exogenous administration of nicotine or nAChR agonists to experimental models of ischemic stroke has been reported to produce conflicting results (either protective or deleterious), which may be largely dependent on the different regiments of drug treatments. With regard to intracerebral hemorrhage, preclinical findings suggest that post-treatment with nAChR agonists is effective in alleviating brain tissue damage and neurological outcome. The beneficial actions of nAChR agonist have also been reported for an experimental model of subarachnoid hemorrhage, which should be confirmed by further investigations. Although smoking has been considered as an important risk factor for stroke episodes, specific targeting of the central nAChRs may prove to be an effective and novel strategy for the treatment of diverse types of cerebrovascular disorders.

We experienced two cases of bone lesions associated with ATL as the primary sites. Case 1 was a 45-year-old man who complained of right hip joint pain. Radiographically, there was an osteolytic lesion in the femoral neck. The patient was positive for HTLV-I antisera and ATL like cells were found in his peripheral blood. Biopsy of the femoral neck demonstrated a Non-Hodgkin lymphoma, diffuse pleomophic cell type. We therefore diagnosed ATL of bone origin. Case 2 was a 62-year-old man who complained of neck pain and eruption. On X-ray, C3 was compressed and biopsy of the eruption, positive HTLV-I antisera and examination of the peripheral blood all confirmed the diagnosis of ATL.Since ATL with bone lesions as the primary site is easily misdiagnosed as a metastatic tumor of unknown origin, careful diagnosis is needed in patients with bone lesions from an unknown primary site.

We report 3 cases of Paraplesia caused by osteoporotic vertebral compression fracture and OYL. All 3 were female patients over 70 years old with severe osteoporosis. Vertebral compression fractures occured at the thoraco-lumbal junction and OYL existed in the next intervertebral space. Radiographic evaluation showed spinal cord compression caused by posterior OYL. The patients were treated surgically with posterior decompression and fusion using a Luque rod or transpedicular screw system. We evaluated the clinical symptoms using the JOA score and Hirabayashi method. Excent for 1 patient whose postoperative JOA score could not be evaluated due to dementia, the percentage of clinical recovery of the other 2 patients was 17% and 88%. We thus concluded that intervertebral fusion should be carried out for osteoporotic patients.

Rheumatoid involvement of the cervical spine is considered relatively frequent, but there are relatively few references in the literature about the involvement of the thoracic and lumbar spine in the course of rheumatoid arthritis. Radiological Study of the lumbar spine in 68 patients with rheumatoid arthritis showed that:1. Osteoporosis was seen in 47 patients (69.1%) and compression fractures in 18 patients (26.5%).2. Osteoporosis and compression fractures were frequent in the RA patient who was older than 60-year-old female and more than Class 2 in Stage III and IV.3. Incomplete paralysis occurred in 4 cases of compression fractures and one of them seemed related to rheumatoid involvement.

Vascularized iliac bone graft was performed in 5 hips (4 cases) of avascular necrosis of the femoral head. All four patients were male whose ages renged from 32 to 36 years. An averafge follow-up was 19 months (range, 14 to 27 moths).Four of the five hips became asymptomatic after surgery with X-ray film showing no progression of the femoral deformity. In one hip, however, moderate pain persisted and the collaps of the femoral head was increasesd.

Ultrasonography of the shoulder joint was investigated in 30 patients who had been suspected rotator cuff tear. In 26 patients, the sonographic fihdings were correlated with arthrography (sensitivity, 86%).The sonographic appearance of the rotator coff tear, be could be classified into three, categories as thinning (15 patients), invisualization (8 patients), and discontinuity (3 patients) of the rotator cuff. Based on these results, ultrasonography is comparable with arthrography for evaluation of the rotator cuff, so we think that ultrasonography can be used as the intial imaging test for the rotator cuff tear.

To study interactions between TGF-beta and decorin, we experimentally induced femoral fracture in rats and immunohistologically examined changes in the distribution of TGF-beta and decorin in the femur 3, 7 and 14 days after fracture. In the areas where endochondral ossification occurred, decorin was detected during differentiation of mesenchymal cells into proliferating chondrocytes, while no TGB-beta was observed during same period. Once chondrocytes had hypertrophied, decorin was no longer observed, while the matrix around the hypertrophic chondrocytes was positively stained for TGB-beta. The disappearance of decorin, almost simultaneously accompanied by the appearance of the active type TGB-beta, suggests that decorin regulates the actions of TGB-beta.