282 research outputs found
A lack of classical Cepheids in the inner part of the Galactic disk
Recent large-scale infrared surveys have been revealing stellar populations
in the inner Galaxy seen through strong interstellar extinction in the disk. In
particular, classical Cepheids with their period-luminosity and period-age
relations are useful tracers of Galactic structure and evolution. Interesting
groups of Cepheids reported recently include four Cepheids in the Nuclear
Stellar Disk (NSD), about 200 pc around the Galactic Centre, found by Matsunaga
et al. and those spread across the inner part of the disk reported by Dekany
and collaborators. We here report our discovery of nearly thirty classical
Cepheids towards the bulge region, some of which are common with Dekany et al.,
and discuss the large impact of the reddening correction on distance estimates
for these objects. Assuming that the four Cepheids in the NSD are located at
the distance of the Galactic Centre and that the near-infrared extinction law,
i.e. wavelength dependency of the interstellar extinction, is not
systematically different between the NSD and other bulge lines-of-sight, most
of the other Cepheids presented here are located significantly further than the
Galactic Centre. This suggests a lack of Cepheids in the inner 2.5 kpc region
of the Galactic disk except the NSD. Recent radio observations show a similar
distribution of star-forming regions.Comment: 8 pages, 4 figures, accepted for publication in MNRA
Pressure-Induced Insulator-to-Metal Transition in van der Waals compound CoPS
We have studied the insulator-to-metal transition and crystal structure
evolution under high pressure in the van der Waals compound CoPS through
electrical resistance, Hall resistance, magnetoresistance,
X-ray diffraction, and Raman scattering measurements. CoPS exhibits a
structural transformation at 7 GPa
accompanied by a 2.9 reduction in the volume per formula unit.
Concomitantly, the electrical resistance decreases significantly, and CoPS
becomes metallic. This metallic CoPS is a hole-dominant conductor with
multiple conduction bands. The linear magnetoresistance and the small volume
collapse at the metallization suggest the incomplete high-spin
low-spin transition in the metallic phase. Thus, the metallic CoPS possibly
possesses an inhomogeneous magnetic moment distribution and short-range
magnetic ordering. This report summarizes the comprehensive phase diagram of
PS ( = V, Mn, Fe, Co, Ni, and Cd) that metalize under pressures.Comment: 14 pages, 6 figures, 1 tabl
Discovery of unusual 3 micron bands on some CM chondrite chips of NIPR and possible link to asteroidal surface minerals
Split luciferase complementation assay to detect regulated protein-protein interactions in rice protoplasts in a large-scale format
© 2014 Fujikawa et al. Background: The rice interactome, in which a network of protein-protein interactions has been elucidated in rice, is a useful resource to identify functional modules of rice signal transduction pathways. Protein-protein interactions occur in cells in two ways, constitutive and regulative. While a yeast-based high-throughput method has been widely used to identify the constitutive interactions, a method to detect the regulated interactions is rarely developed for a large-scale analysis. Results: A split luciferase complementation assay was applied to detect the regulated interactions in rice. A transformation method of rice protoplasts in a 96-well plate was first established for a large-scale analysis. In addition, an antibody that specifically recognizes a carboxyl-terminal fragment of Renilla luciferase was newly developed. A pair of antibodies that recognize amino- and carboxyl- terminal fragments of Renilla luciferase, respectively, was then used to monitor quality and quantity of interacting recombinant-proteins accumulated in the cells. For a proof-of-concept, the method was applied to detect the gibberellin-dependent interaction between GIBBERELLIN INSENSITIVE DWARF1 and SLENDER RICE 1. Conclusions: A method to detect regulated protein-protein interactions was developed towards establishment of the rice interactome
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