37 research outputs found
Meson Synchrotron Emission from Central Engines of Gamma-Ray Bursts with Strong Magnetic Fields
Gamma-ray bursts (GRBs) are presumed to be powered by still unknown central
engines for the timescales in the range a few s. We propose that the
GRB central engines would be a viable site for strong meson synchrotron
emission if they were the compact astrophysical objects such as neutron stars
or rotating black holes with extremely strong magnetic fields and if protons or heavy nuclei were accelerated to ultra-relativistic
energies of order . We show that the charged scalar
mesons like and heavy vector mesons like , which have several
decay modes onto , could be emitted with high intensity a thousand
times larger than photons through strong couplings to ultra-relativistic
nucleons. These meson synchrotron emission processes eventually produce a burst
of very high-energy cosmic neutrinos with . These
neutrinos are to be detected during the early time duration of short GRBs.Comment: 12 pages, 4 figures. Accepted for publication in the Astrophysical
Journal Letter
Long-term incidence and prognostic factors of the progression of new coronary lesions in Japanese coronary artery disease patients after percutaneous coronary intervention
Impact of aging on the clinical outcomes of Japanese patients with coronary artery disease after percutaneous coronary intervention
Effects of statin treatment in patients with coronary artery disease and chronic kidney disease
Clear and transparent nanocrystals for infrared-responsive carrier transfer
赤外光を電気エネルギーや信号に変換する無色透明な材料の開発に成功 --見えない電子デバイスの開発へ道--. 京都大学プレスリリース. 2019-02-13.An Author Correction to this article was published on 17 April 2019. https://doi.org/10.1038/s41467-019-09888-2Infrared-light-induced carrier transfer is a key technology for ‘invisible’ optical devices for information communication systems and energy devices. However, clear and colourless photo-induced carrier transfer has not yet been demonstrated in the field of photochemistry, to the best of our knowledge. Here, we resolve this problem by employing short-wavelength-infrared (1400–4000 nm) localized surface plasmon resonance-induced electron injection from indium tin oxide nanocrystals to transparent metal oxides. The time-resolved infrared measurements visualize the dynamics of the carrier in this invisible system. Selective excitation of localized surface plasmon resonances causes hot electron injection with high efficiency (33%) and long-lived charge separation (~ 2–200 μs). We anticipate our study not only provides a breakthrough for plasmonic carrier transfer systems but may also stimulate the invention of state-of-the-art invisible optical devices
A new echocardiographic method for identifying vortex flow in the left ventricle: numerical validation
A new mathematical method for estimating velocity vectors from color Doppler datasets is proposed to image blood flow dynamics; this method has been called echodynamography or vector flow mapping (VFM). In this method, the concept of stream function is exploited to expand a 2-D distribution of radial velocities in polar coordinates, observed with color Doppler, to a 2-D distribution of velocity vectors. This study was designed to validate VFM using 3-D numerical flow models. Velocity fields were reconstructed from the virtual color Doppler datasets derived from the models. VFM captured the gross features of flow structures and produced comparable images of the distribution of vorticity, which correlated significantly with the original field (for velocity magnitudes, standard error of estimate = 0.003 to 0.007m/s; for vorticity, standard error of estimate = 0.35 to 2.01/s). VFM may be sensitive for depicting flow structures derived from color Doppler velocities with reasonable accuracy
Author correction: Clear and transparent nanocrystals for infrared-responsive carrier transfer
The original version of this Article omitted the fourth author Taizo Yoshinaga, who is from the 'Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Japan'. Consequently, the third sentence of the Author Contributions, 'M.S. and M.K. synthesized the ITO NCs and ITO/semiconductor oxides' was revised to 'M.S., M.K. and T.Y. synthesized the ITO NCs and ITO/semiconductor oxides'. This has been corrected in both the PDF and HTML versions of the Article