294 research outputs found
Generation of high circular polarization of interstellar Lyman radiation triggering biological homochirality
The homochirality of biological molecules on the Earth is a long-standing
mystery regarding the origin of life. Circularly polarized ultraviolet (UV)
light could induce the enantiomeric excess of biological molecules in the
interstellar medium, leading to the homochirality on the earth. By performing
3D radiation transfer simulations with multiple scattering processes in
interstellar dusty slabs, we study the generation of circular polarization (CP)
of ultraviolet light at Lyman () as well
as in the near-infrared (NIR, ) wavelengths. Our
simulations show that the distributions of CP exhibit a symmetric quadrupole
pattern, regardless of wavelength and viewing angle. The CP degree of scattered
light from a dusty slab composed of aligned grains is percent for
Ly and percent at NIR wavelengths in the case of oblate grains
with an MRN size distribution. We find that the CP degree of Ly is well
correlated with that in the NIR regardless of viewing angles, whilst being a
factor of higher. Thus, high CP of Ly is expected in sites
where NIR CP is detected. We suggest that such circularly polarized Ly
may initiate the enantiomeric excess of biological molecules in space.Comment: 10 pages, 11 figures, accepted for publication in MNRA
1-[(2-Methyl-8-quinolyl)aminomethylene]naphthalen-2(1H)-one
The molecule of the title compound, C21H16N2O, exists in the keto form and the C=O and N—H bonds are mutually cis in the crystal structure, although an enol form would be possible through tautomerism. The dihedral angle between the quinoline and the naphthalene systems is 22.04 (2)°. A bifurcated intramolecular N—H⋯(O,N) hydrogen bond is present
Effect of some naturally occurring iron ion chelators on the formation of radicals in the reaction mixtures of rat liver microsomes with ADP, Fe3+ and NADPH
In order to clarify the mechanism by polyphenols of protective effects against oxidative damage or by quinolinic acid of its neurotoxic and inflammatory actions, effects of polyphenols or quinolinic acid on the radical formation were examined. The ESR measurements showed that some polyphenols such as caffeic acid, catechol, gallic acid, D-(+)-catechin, L-dopa, chlorogenic acid and L-noradrenaline inhibited the formation of radicals in the reaction mixture of rat liver microsomes with ADP, Fe3+ and NADPH. The ESR measurements showed that α-picolinic acid, 2,6-pyridinedicarboxylic acid and quinolinic acid (2,3-pyridinedicarboxylic acid) enhanced the formation of radicals in the reaction mixture of rat liver microsomes with Fe3+ and NADPH. Caffeic acid and α-picolinic acid had no effects on the formation of radicals in the presence of EDTA, suggesting that the chelation of iron ion seems to be related to the inhibitory and enhanced effects. The polyphenols may exert protective effects against oxidative damage of erythrocyte membrane, ethanol-induced fatty livers, cardiovascular diseases, inflammatory and cancer through the mechanism. On the other hand, quinolinic acid may exert its neurotoxic and inflammatory effects because of the enhanced effect on the radical formation
Structure of the Milky Way stellar halo out to its outer boundary with blue horizontal-branch stars
We present the structure of the Milky Way stellar halo beyond Galactocentric
distances of kpc traced by blue horizontal-branch (BHB) stars, which
are extracted from the survey data in the Hyper Suprime-Cam Subaru Strategic
Program (HSC-SSP). We select BHB candidates based on photometry,
where the -band is on the Paschen series and the colors that involve the
-band are sensitive to surface gravity. About 450 BHB candidates are
identified between kpc and 300 kpc, most of which are beyond the reach
of previous large surveys including the Sloan Digital Sky Survey. We find that
the global structure of the stellar halo in this range has substructures, which
are especially remarkable in the GAMA15H and XMM-LSS fields in the HSC-SSP. We
find that the stellar halo can be fitted to a single power-law density profile
with an index of () with (without) these fields and
its global axial ratio is (). Thus, the stellar halo may be
significantly disturbed and be made in a prolate form by halo substructures,
perhaps associated with the Sagittarius stream in its extension beyond kpc. For a broken power-law model allowing different power-law indices
inside/outside a break radius, we obtain a steep power-law slope of outside a break radius of kpc ( kpc) for the case
with (without) GAMA15H and XMM-LSS. This radius of kpc might be as close
as a halo boundary if there is any, although larger BHB sample is required from
further HSC-SSP survey to increase its statistical significance.Comment: 12 pages, 8 figures, revised version, accepted for publication in
PAS
Clinical characteristics and outcomes of patients with small cell lung cancer detected by CT screening
The present study was performed to evaluate the clinical characteristics and survival outcomes in patients with small cell lung cancer (SCLC) detected by low-dose computed tomography (CT). We retrospectively reviewed clinical records of patients with SCLC treated at our hospital between 1997 and 2011 and selected patients with SCLC detected by CT screening. We identified 12 patients (male/female 11/1; mean age 67.8 years old. Nine patients had limited disease (LD), and 3 had extensive disease (ED). Five LD patients underwent thoracic surgery, and the pathological staging information included stage IA (n = 1), IB (n = 1), IIA (n = 1), and IIIB (n = 2). Although 2 patients with pathological stages IA and IB had >10-year survival, the median survival times (MST) in LD and ED were 25 months (95 % CI 17.0-32.9) and 16 months (95 % CI; not evaluated), respectively. In addition, MST in 12 patients was not significantly different from that in SCLC patients in general care in our hospital. This analysis suggested that CT screening contributes to the detection of early-stage SCLC in patients that are potentially suitable for surgery, but it remains unclear how to improve clinical outcome in patients with SCLC.ArticleMEDICAL ONCOLOGY. 30(3):623 (2013)journal articl
近赤外線分光法を用いた局所酸素飽和度による熱傷深度測定の検討
The burn severity depends on the wound depth and area affected. Hitherto burn depth has been judged mainly by visual observation, although concerns have been raised about its validity. The regional tissue blood flow (rTBF) measured by laser Doppler imaging (LDI) in damaged tissue correlates with the depth. However, very few reports are available on the significance of the regional tissue oxygen saturation (rSO2) as an indicator of burn depth. We investigated whether rSO2 by Near-infrared spectroscopy (NIRS) in burn injuries correlates with rTBF by LDI, which would facilitate quantification of the severity of the tissue damage. Methods: We measured rTBF and rSO2 in 50 lesions from 14 patients of burn injury within 24 hours after injury. The correlation between rTBF and rSO2 was evaluated by Spearman rank correlation analysis. Results: The rSO2 (%; range, 52-82) by NIRS and the rTBF (perfusion unit; range, 61-704) by LDI in burn lesions were positively correlated (r=0.755, p<0.001). This statistically positive correlation still remained significant (r=0.678, p<0.001) after the rSO2 values were standardized. Conclusion: This study suggests that NIRS determination of rSO2 in burn injuries shows promise as a reliable and quick method to estimate the depth of burn lesion.博士(医学)・乙第1343号・平成26年7月22日© 2014 Seki Tadahiko et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Effects of a multi-quark interaction on color superconducting phase transition in an extended NJL model
We study the interplay of the chiral and the color superconducting phase
transitions in an extended Nambu--Jona-Lasinio model with a multi-quark
interaction that produces the nonlinear chiral-diquark coupling. We observe
that this nonlinear coupling adds up coherently with the \omega^2 interaction
to produce the chiral-color superconductivity coexistence phase or cancel each
other depending on its sign. We discuss that large coexistence region in the
phase diagram is consistent with the quark-diquark picture for the nucleon
whereas its smallness is the prerequisite for the applicability of the
Ginzburg-Landau approach.Comment: 9 pages, 3 figure
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