Time Evolution of Relativistic Force-Free Fields Connecting a Neutron Star and its Disk

We study the magnetic interaction between a neutron star and its disk by solving the time-dependent relativistic force-free equations. At the initial state, we assume that the dipole magnetic field of the neutron star connects the neutron star and its equatorial disk, which deeply enters into the magnetosphere of the neutron star. Magnetic fields are assumed to be frozen to the star and the disk. The rotation of the neutron star and the disk is imposed as boundary conditions. We apply Harten-Lax-van Leer (HLL) method to simulate the evolution of the star-disk system. We carry out simulations for (1) a disk inside the corotation radius, in which the disk rotates faster than the star, and (2) a disk outside the corotation radius, in which the neutron star rotates faster than the disk. Numerical results indicate that for both models, the magnetic field lines connecting the disk and the star inflate as they are twisted by the differential rotation between the disk and the star. When the twist angle exceeds pi radian, the magnetic field lines expand with speed close to the light speed. This mechanism can be the origin of relativistic outflows observed in binaries containing a neutron star.Comment: 10 pages, 6figures, accepted for publication in PAS

Quantitative Temperature Dependence of Longitudinal Spin Seebeck Effect at High Temperatures

This article reports temperature-dependent measurements of longitudinal spin Seebeck effects (LSSEs) in Pt/Y$_3$Fe$_5$O$_{12}$ (YIG)/Pt systems in a high temperature range from room temperature to above the Curie temperature of YIG. The experimental results show that the magnitude of the LSSE voltage in the Pt/YIG/Pt systems rapidly decreases with increasing the temperature and disappears above the Curie temperature. The critical exponent of the LSSE voltage in the Pt/YIG/Pt systems at the Curie temperature was estimated to be 3, which is much greater than that for the magnetization curve of YIG. This difference highlights the fact that the mechanism of the LSSE cannot be explained in terms of simple static magnetic properties in YIG.Comment: 9 pages, 5 figures, 1 tabl

Lymph Node Dissection along the Recurrent Laryngeal Nerve in Video-Assisted Thoracoscopic Surgery (VATSE) for Esophageal Squamous Cell Carcinoma

Esophageal carcinoma is the ninth most common cancer in the world, which is frequently seen in Asia and east Africa. Around 80% of all cases occurred in less-developed regions. Two major histological subtypes of esophageal carcinoma, adenocarcinoma and squamous cell carcinoma, are known to differ greatly in terms of risk factor, epidemiology, male to female ratios, and incidence. Lymph node metastasis is a crucial factor in staging and prognosis is associated with surgical treatment and a major lymphatic chain into the neck. Esophageal adenocarcinoma (EAC) is mainly detected at the lower third of the thoracic esophagus or esophago-gastric-junction (EGJ) and metastasizes mainly to lymph nodes of the lesser sac, celiac regions and lower mediastinal. Esophageal squamous cell carcinoma (ESCC) has a predilection for metastasis to the lymph nodes of the cervical region including recurrent laryngeal nerve (RLN) on both sides. Lymph node dissection is vital yet difficult, left-side lymph node dissection especially requires expertise. There are some reports on lymph node dissection in the prone position by video-assisted thoracoscopic surgery of the esophagus (VATS-E) along the left RLN in Japan and China. We also introduce a stripping method for lymph node dissection in this site