217 research outputs found
Alloxazinium-Resins as Readily Available and Reusable Oxidation Catalysts
N5-Modified alloxazinium salts including 5-ethyl-1,3-dimethylalloxazinium and 5-ethyl-1,3-dimethyl-8-(trifluoromethyl)alloxazinium salts were readily prepared as alloxazinium-resins from the corresponding N5-unmodified ingredients via the aerobic oxidation—ion exchange protocol, previously introduced by us for the preparation of isoalloxazine analogues, and their catalysis and reusability in H2O2 oxidations were evaluated
Global Mapping of Surface Composition on an Exo-Earth Using Sparse Modeling
The time series of light reflected from exoplanets by future direct imaging
can provide spatial information with respect to the planetary surface. We apply
sparse modeling to the retrieval method that disentangles the spatial and
spectral information from multi-band reflected light curves termed as
spin-orbit unmixing. We use the -norm and the Total Squared Variation
norm as regularization terms for the surface distribution. Applying our
technique to a toy model of cloudless Earth, we show that our method can infer
sparse and continuous surface distributions and also unmixed spectra without
prior knowledge of the planet surface. We also apply the technique to the real
Earth data as observed by DSCOVR/EPIC. We determined the representative
components that can be interpreted as cloud and ocean. Additionally, we found
two components that resembled the distribution of land. One of the components
captures the Sahara Desert, and the other roughly corresponds to vegetation
although their spectra are still contaminated by clouds. Sparse modeling
significantly improves the geographic retrieval, in particular, of cloud and
leads to higher resolutions for other components when compared with spin-orbit
unmixing using Tikhonov regularization.Comment: 26 pages, 10 figures, accepted for publication in Ap
Determination of the genetic structure of remnant Morus boninensis Koidz. trees to establish a conservation program on the Bonin Islands, Japan
BACKGROUND: Morus boninensis, is an endemic plant of the Bonin (Ogasawara) Islands of Japan and is categorized as "critically endangered" in the Japanese red data book. However, little information is available about its ecological, evolutionary and genetic status, despite the urgent need for guidelines for the conservation of the species. Therefore, we adopted Moritz's MU concept, based on the species' current genetic structure, to define management units and to select mother tree candidates for seed orchards. RESULTS: Nearly all individuals of the species were genotyped on the basis of seven microsatellite markers. Genetic diversity levels in putative natural populations were higher than in putative man-made populations with the exception of those on Otouto-jima Island. This is because a limited number of maternal trees are likely to have been used for seed collection to establish the man-made populations. A model-based clustering analysis clearly distinguished individuals into nine clusters, with a large difference in genetic composition between the population on Otouto-jima Island, the putative natural populations and the putative man-made populations. The Otouto-jima population appeared to be genetically differentiated from the others; a finding that was also supported by pairwise F(ST )and R(ST )analysis. Although multiple clusters were detected in the putative man-made populations, the pattern of genetic diversity was monotonous in comparison to the natural populations. CONCLUSION: The genotyping by microsatellite markers revealed strong genetic structures. Typically, artificial propagation of this species has ignored the genetic structure, relying only on seeds from Otouto-jima for replanting on other islands, because of a problem with inter-specific hybridization on Chichi-jima and Haha-jima Islands. However, this study demonstrates that we should be taking into consideration the genetic structure of the species when designing a propagation program for the conservation of this species
Local Genetic Differentiation within Rebun Island in Cypripedium macranthos var. rebunense Revealed by Genome-wide SNP Analysis Using MIG-seq
Poster Presentation
Can Ground-based Telescopes Detect The Oxygen 1.27 Micron Absorption Feature as a Biomarker in Exoplanets ?
The oxygen absorption line imprinted in the scattered light from the
Earth-like planets has been considered the most promising metabolic biomarker
of the exo-life. We examine the feasibility of the detection of the 1.27 micron
oxygen band from habitable exoplanets, in particular, around late- type stars
observed with a future instrument on a 30 m class ground-based telescope. We
analyzed the night airglow around 1.27 micron with IRCS/echelle spectrometer on
Subaru and found that the strong telluric emission from atmospheric oxygen
molecules declines by an order of magnitude by midnight. By compiling nearby
star catalogs combined with the sky background model, we estimate the
detectability of the oxygen absorption band from an Earth twin, if it exists,
around nearby stars. We find that the most dominant source of photon noise for
the oxygen 1.27 micron band detection comes from the night airglow if the
contribution of the stellar PSF halo is suppressed enough to detect the planet.
We conclude that the future detectors for which the detection contrast is
limited by photon noise can detect the oxygen 1.27 micron absorption band of
the Earth twins for ~50 candidates of the late type star. This paper
demonstrates the importance of deploying small inner working angle efficient
coronagraph and extreme adaptive optics on extremely large telescopes, and
clearly shows that doing so will enable study of potentially habitable planets.Comment: 11 pages, 9 figures, accepted for publication in The Astrophysical
Journa
Complete Dissection of a Hepatic Segment after Blunt Abdominal Injury Successfully Treated by Anatomical Hepatic Lobectomy: Report of a Case
A 21-year-old male patient was transferred to the emergency room of our hospital after suffering seat belt abdominal injury in a traffic accident. Abdominal computed tomography revealed a massive hematoma in the abdominal cavity associated with deep hepatic lacerations in the right lobe. The presence of a solid tissue possibly containing pneumobilia was observed above the greater omentum. These findings were consistent with a tentative diagnosis of hepatic laceration due to blunt trauma; therefore, this prompted us to perform emergency laparotomy. The operative findings revealed a massive hematoma and pulsatile bleeding from the lacerated liver and a retroperitoneal hepatoma, which was most likely due to subcapsular injury of the right kidney. In accordance with the preoperative imaging studies, a pale liver fragment on the greater omentum was observed, which was morphologically consistent with the defect in the posterior segment of the liver. Since the damaged area of the liver broadly followed the course of the middle hepatic vein, we carefully inspected and isolated the inflow vessels and eventually performed a right hepatic lobectomy. The patient's postoperative course was uneventful, and he was doing well at 10 months after surgery
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