Both start-up and sustainment of plasma were successfully achieved by fully non- inductive current drive using microwave with a frequency of 8.2 GHz. Plasmas current of 15 kA was implemented for 1 s. Magnetic surface ...Both start-up and sustainment of plasma were successfully achieved by fully non- inductive current drive using microwave with a frequency of 8.2 GHz. Plasmas current of 15 kA was implemented for 1 s. Magnetic surface reconstruction exhibited a plasma shape with an aspect ratio of below 1.5. The plasma current was dependent significantly on the launched microwave power and vertical magnetic field, while not affected by the mode of launched wave and the toroidal refractive index. Hard X-ray （HXR） emitted from energetic electrons accelerated by the microwave was observed, and the discharge with a plasma current over 4 kA followed the same trend as the number of photons of 10 keV to 12 keV. This suggests that the plasma current may be driven by energetic electrons. Based on the experimental conditions, alternative explanations of how the plasma current could be driven are discussed.展开更多
We encountered a 36-year-old female who developed extracranial vertebral artery dissociation (EVAD), which is a rare condition in Japan. The disease developed with sudden severe right side neck pain and right upper ar...We encountered a 36-year-old female who developed extracranial vertebral artery dissociation (EVAD), which is a rare condition in Japan. The disease developed with sudden severe right side neck pain and right upper arm pain. No abnormality was observed in the spinal canal, intervertebral discs, spinal cord, or nerve roots on MRI of the cervical spine, but dilation and double lumen were noted in the vertebral artery (VA) at the C4/5 level. The presence of aneurysm was confirmed by VA angiography, and EVAD was diagnosed. The symptoms were resolved by conservative treatment of pain, and the aneurysm shrank and disappeared with time on VA angiography. Even though neck and upper limb pain are the only clinical symptom and there is no brain dysfunction, such as disturbance of consciousness and vertigo, when symptoms develop acutely, this pathology should be included in differential diagnosis and orthopedists should carefully observe the vertebral artery, as well as the spinal canal, in evaluating cervical MRI.展开更多
The experiments with solar, atmospheric, reactor and accelerator neutrinos have provided compelling evidences for oscillations of neutrinos caused by nonzero neutrino masses and neutrino mixing. The data imply the exi...The experiments with solar, atmospheric, reactor and accelerator neutrinos have provided compelling evidences for oscillations of neutrinos caused by nonzero neutrino masses and neutrino mixing. The data imply the existence of 3-neutrino mixing in vacuum. We review the theory of neutrino oscillations, the phenomenology of neutrino mixing, the problem of the nature - Dirac or Majorana, of massive neutrinos, the issue of CP violation in the lepton sector, and the current data on the neutrino masses and mixing parameters. The open questions and the main goals of future research in the field of neutrino mixing and oscillations are outlined.展开更多
文摘Both start-up and sustainment of plasma were successfully achieved by fully non- inductive current drive using microwave with a frequency of 8.2 GHz. Plasmas current of 15 kA was implemented for 1 s. Magnetic surface reconstruction exhibited a plasma shape with an aspect ratio of below 1.5. The plasma current was dependent significantly on the launched microwave power and vertical magnetic field, while not affected by the mode of launched wave and the toroidal refractive index. Hard X-ray （HXR） emitted from energetic electrons accelerated by the microwave was observed, and the discharge with a plasma current over 4 kA followed the same trend as the number of photons of 10 keV to 12 keV. This suggests that the plasma current may be driven by energetic electrons. Based on the experimental conditions, alternative explanations of how the plasma current could be driven are discussed.
文摘We encountered a 36-year-old female who developed extracranial vertebral artery dissociation (EVAD), which is a rare condition in Japan. The disease developed with sudden severe right side neck pain and right upper arm pain. No abnormality was observed in the spinal canal, intervertebral discs, spinal cord, or nerve roots on MRI of the cervical spine, but dilation and double lumen were noted in the vertebral artery (VA) at the C4/5 level. The presence of aneurysm was confirmed by VA angiography, and EVAD was diagnosed. The symptoms were resolved by conservative treatment of pain, and the aneurysm shrank and disappeared with time on VA angiography. Even though neck and upper limb pain are the only clinical symptom and there is no brain dysfunction, such as disturbance of consciousness and vertigo, when symptoms develop acutely, this pathology should be included in differential diagnosis and orthopedists should carefully observe the vertebral artery, as well as the spinal canal, in evaluating cervical MRI.
文摘The experiments with solar, atmospheric, reactor and accelerator neutrinos have provided compelling evidences for oscillations of neutrinos caused by nonzero neutrino masses and neutrino mixing. The data imply the existence of 3-neutrino mixing in vacuum. We review the theory of neutrino oscillations, the phenomenology of neutrino mixing, the problem of the nature - Dirac or Majorana, of massive neutrinos, the issue of CP violation in the lepton sector, and the current data on the neutrino masses and mixing parameters. The open questions and the main goals of future research in the field of neutrino mixing and oscillations are outlined.
