Significantly high polarization degree of the very low-albedo asteroid (152679) 1998 KU2_\mathrm{2}

We present a unique and significant polarimetric result regarding the near-Earth asteroid (152679) 1998 KU$_\mathrm{2}$ , which has a very low geometric albedo. From our observations, we find that the linear polarization degrees of 1998 KU$_\mathrm{2}$ are 44.6 $\pm$ 0.5\% in the R$_\mathrm{C}$ band and 44.0 $\pm$ 0.6\% in the V band at a solar phase angle of 81.0\degr. These values are the highest of any known airless body in the solar system (i.e., high-polarization comets, asteroids, and planetary satellites) at similar phase angles. This polarimetric observation is not only the first for primitive asteroids at large phase angles, but also for low-albedo (< 0.1) airless bodies. Based on spectroscopic similarities and polarimetric measurements of materials that have been sorted by size in previous studies, we conjecture that 1998 KU$_\mathrm{2}$ has a highly microporous regolith structure comprising nano-sized carbon grains on the surface.Comment: 9 pages, 5 figures, and 3 tables, accepted for publication in A&

WIDGET: System Performance and GRB Prompt Optical Observations

The WIDeField telescope for Gamma-ray burst Early Timing (WIDGET) is used for a fully automated, ultra-wide-field survey aimed at detecting the prompt optical emission associated with Gamma-ray Bursts (GRBs). WIDGET surveys the HETE-2 and Swift/BAT pointing directions covering a total field of view of 62 degree x 62 degree every 10 secounds using an unfiltered system. This monitoring survey allows exploration of the optical emission before the gamma-ray trigger. The unfiltered magnitude is well converted to the SDSS r' system at a 0.1 mag level. Since 2004, WIDGET has made a total of ten simultaneous and one pre-trigger GRB observations. The efficiency of synchronized observation with HETE-2 is four times better than that of Swift. There has been no bright optical emission similar to that from GRB 080319B. The statistical analysis implies that GRB080319B is a rare event. This paper summarizes the design and operation of the WIDGET system and the simultaneous GRB observations obtained with this instrument.Comment: 19 pages, 11 figures, Accepted to appear in PAS

Non-catalytic dehydration of N,N'-diacetylchitobiose in high-temperature water

Accepted 28 Jul 2014Non-catalytic synthesis of 4-O-β-2-acetamido-2-deoxy-D-glucopyranosyl 2-acetamido-2,3-dideoxydidehydro-glucopyranose (GND) from chitin disaccharide, N,N′-diacetylchitobiose (GlcNAc)2, was achieved, with a maximum yield of 24.7% in high-temperature water at 120–220 °C and 25 MPa with a reaction time of 8–39 s.ArticleRSC ADVANCES. 4(64):33651-33657 (2014)journal articl

Purification, molecular cloning and functional characterization of flavonoid C-glucosyltransferases from Fagopyrum esculentum M. (buckwheat) cotyledon

C-Glycosides are characterized by their C-C bonds in which the anomeric carbon of the sugar moieties is directly bound to the carbon atom of aglycon. C-Glycosides are remarkably stable, as their C-C bonds are resistant to glycosidase or acid hydrolysis. A variety of plant species are known to accumulate C-glycosylflavonoidshowever, the genes encoding for enzymes that catalyze C-glycosylation of flavonoids have been identified only from Oryza sativa (rice) and Zea mays (maize), and have not been identified from dicot plants. In this study, we identified the C-glucosyltransferase gene from the dicot plant Fagopyrum esculentumM. (buckwheat). We purified two isozymes from buckwheat seedlings that catalyze C-glucosylation of 2-hydroxyflavanones, which are expressed specifically in the cotyledon during seed germination. Following purification we isolated the cDNA corresponding to each isozyme [FeCGTa (UGT708C1) and FeCGTb (UGT708C2)]. When expressed in Escherichia coli, both proteins demonstrated C-glucosylation activity towards 2-hydroxyflavanones, dihydrochalcone, trihydroxyacetophenones and other related compounds with chemical structures similar to 2,4,6-trihydroxyacetophenone. Molecular phylogenetic analysis of plant glycosyltransferases shows that flavonoid C-glycosyltransferases form a different clade with other functionally analyzed plant glycosyltransferases.ArticlePLANT JOURNAL. 80(3):437-448 (2014)journal articl

A pediatric case of productive cough caused by novel variants in DNAH9

We report the first Japanese case of primary ciliary dyskinesia caused by DNAH9 variations. The patient, a 5-year-old girl, had repeated episodes of productive cough after contracting the common cold at the age of 1 year and 6 months. She did not have a situs abnormality or congenital heart defect. We identified two novel DNAH9 variants, NM_001372.3: c. [1298C>G];[5547_5550delTGAC], (p.[Ser433Cys];[Asp1850fs])