102 research outputs found
Extension of measurement range in OCDR based on double-modulation scheme
We extend the measurement range of optical correlation-domain reflectometry
(OCDR) by modulating the laser output frequency at two frequencies, while
preserving spatial resolution. We demonstrate distributed reflectivity sensing
with a ten-fold extended measurement range.Comment: 4 pages, 6 figure
Observation of Rayleigh scattering by simplified optical correlation-domain reflectometry without frequency shifter
We present a method for measuring the transmission loss of an optical fiber
using simplified optical correlation-domain reflectometry. By intentionally
lowering the spatial resolution of the system, we observe the Rayleigh
scattered signal for the first time without the need for a frequency shifter.
Using this method, we simultaneously measure the transmission loss, location,
and loss of faulty connections along a 10-km-long fiber under test by
performing distributed reflected-power measurements of Rayleigh scattering and
Fresnel reflection
Preoperative Virtual Navigation with 3D-CT Volume Rendering for Single Minimum Incision Endoscopic Nephron-Sparing Surgery on Renal Tumors
Molecular cloning of a novel putative G protein-coupled receptor (GPCR21) which is expressed predominantly in mouse central nervous system
AbstractA novel cDNA clone encoding a putative G protein-coupled receptor (named GPCR21) was isolated from a mouse brain cDNA library along with its homologue, GPCR01 (the mouse counterpart of previously reported rat receptor R334 [(1991) FEBS Lett. 292, 243-248]) by the polymerase chain reaction using degenerate oligonucleotide primers. Northern blotting and reverse transcription-polymerase chain reaction analyses showed predominant expression of these two receptors in the central nervous system. In situ hybridization analysis revealed their prominent expression in the limbic system and further demonstrated the differential distribution of their mRNAs in mouse brain. Although the ligands for these receptors are yet to be identified, the significant sequence homology between these receptors suggests that they constitute a new receptor subfamily and they possibly represent different receptor subtypes for an unknown neurotransmitter
Special Relativistic Simulations of Magnetically-dominated Jets in Collapsing Massive Stars
We perform a series of two-dimensional magnetohydrodynamic core-collapse
simulations of rapidly rotating and strongly magnetized massive stars. To study
the properties of magnetic explosions for a longer time stretch of postbounce
evolution, we develop a new code under the framework of special relativity
including a realistic equation of state with a multiflavor neutrino leakage
scheme. Our results show the generation of the magnetically-dominated jets in
the two ways. One is launched just after the core-bounce in a prompt way and
another is launched at ms after the stall of the prompt shock. We
find that the shock-revival occurs when the magnetic pressure becomes strong,
due to the field wrapping, enough to overwhelm the ram pressure of the
accreting matter. The critical toroidal magnetic fields for the magnetic
shock-revival are found to be universal of behind the
jets. We point out that the time difference before the shock-revival has a
strong correlation with the explosions energies. Our results suggest that the
magnetically dominated jets are accompanied by the formation of the magnetars.
Since the jets are mildly relativistic, we speculate that they might be the
origin of some observed X-ray flashes.Comment: 50 pages, 14 figures, Accepted to ApJ, A paper with high-resolution
figures available at
http://www-utap.phys.s.u-tokyo.ac.jp/~takiwaki/res/index-j.htm
- …