82 research outputs found
MHD Equilibrium and Stability of Spherical Tokamak Plasma with Current Hole
The potential characteristics of spherical tokamak configurations with current hole are investigated from the point of view of magnetohydrodynamic (MHD) equilibrium and stability. The effect of the toroidal shear flows is also considered by using a modified Grad-Shafranov equation. Linear and nonlinear stability for low-n kink modes and intermediate-n ballooning mode is analyzed by means of numerical simulations
Dynamics of spherical tokamak plasma on the internal reconnection event
Nonlinear magnetohydrodynamic (MHD) simulations are executed to investigate the dynamical behavior of the relaxation phenomenon observed in spherical tokamak (ST) plasma that is known as the Internal Reconnection Event (IRE). The simulation results successfully reproduce several key features of IRE, and the physical mechanisms are revealed. A sudden collapse of the pressure profile takes place as a result of a nonlinear time development of a pressure-driven instability. A magnetic reconnection induced between the internal and the external magnetic field is found to play a crucial role in determining the nature of the overall process, namely, the rapid expulsion of the plasma heat energy due to the pressure imbalance along the reconnected field lines, and the large distortion in the overall shape. The resultant deformations in overall shape of the plasma are in good agreement with the experimental observations
ๅฐ็น้๏ผๅ ้ฒ็ๆๆ ธ่ๅ็ ็ฉถใฎ็พ็ถใจๅฑ้ใ๏ผ๏ผ็ธ่ฃ็็ๆใตใคใฏใซๅฎ็พใซๅใใๅ ้ฒ็ๆๆ ธ่ๅ็ ็ฉถใฎใใใ
Simulation Data Analysis by Virtual Reality System
We introduce new software for analysis of time-varying simulation data and new approach for contribution of simulation to experiment by virtual reality (VR) technology. In the new software, the objects of time-varying field are visualized in VR space and the particle trajectories in the time-varying electromagnetic field are also traced. In the new approach, both simulation results and experimental device data are simultaneously visualized in VR space. These developments enhance the study of the phenomena in plasma physics and fusion plasmas
ใใคใฏใญๆณขCTใใณใขใฐใฉใใฃใฎ้็บ
24ๅใฎๅบๅฎใใคใใผใซใขใณใใใ็จใใฆไธๆฌกๅ
ใใคใฏใญๆณขCTๅฎ้จใ่กใ๏ผในใผใใผใณใณใใฅใผใฟใ็จใใฆForward-Backward Time Stepping๏ผFBTS๏ผๆณใซใใCT่จ็ฎใ่กใฃใ๏ผใใฎ็ตๆๅพใใใ็ฅ่ฆใฏ๏ผFBTSๆณใ้้ณใซๅผทใใใจ๏ผๅใณ่จ็ฎใฎๅๆ่จญๅฎใใญใฃใชใใฌใผใทใงใณ่จญๅฎใ็ฒพๅบฆๅไธใซ้่ฆใชใใจใงใใ๏ผใพใ่จ็ฎใขใใซๅใๅฎนๆใชๅบๅธฏๅๅนณ้ขใขใณใใใฎ้็บใ่กใฃใ๏ผใใใใฎ็ฅ่ฆใ็ใใ๏ผFBTSๆณใใคใฏใญๆณขCTใใณใขใฐใฉใใฃ่ฃ
็ฝฎใฎๆฆๅฟต่จญ่จใ่กใฃใ
Generation of TetrafluoroethyleneโPropylene Elastomer-Based Microfluidic Devices for Drug Toxicity and Metabolism Studies
ใใ็ด ็ณปใจใฉในใใใผ็ด ๆใ็จใใ่่ใใใใฎ้็บใจ่ฌ็ฉไปฃ่ฌใปๆฏๆง่ฉฆ้จใธใฎๅฟ็จ. ไบฌ้ฝๅคงๅญฆใใฌในใชใชใผใน. 2021-09-16.Drug testing on miniatured livers. ไบฌ้ฝๅคงๅญฆใใฌในใชใชใผใน. 2021-09-17.Polydimethylsiloxane (PDMS) is widely used to fabricate microfluidic organs-on-chips. Using these devices (PDMS-based devices), the mechanical microenvironment of living tissues, such as pulmonary respiration and intestinal peristalsis, can be reproduced in vitro. However, the use of PDMS-based devices in drug discovery research is limited because of their extensive absorption of drugs. In this study, we investigated the feasibility of the tetrafluoroethyleneโpropylene (FEPM) elastomer to fabricate a hepatocyte-on-a-chip (FEPM-based hepatocyte chip) with lower drug absorption. The FEPM-based hepatocyte chip expressed drug-metabolizing enzymes, drug-conjugating enzymes, and drug transporters. Also, it could produce human albumin. Although the metabolites of midazolam and bufuralol were hardly detected in the PDMS-based hepatocyte chip, they were detected abundantly in the FEPM-based hepatocyte chip. Finally, coumarin-induced hepatocyte cytotoxicity was less severe in the PDMS-based hepatocyte chip than in the FEPM-based hepatocyte chip, reflecting the different drug absorptions of the two chips. In conclusion, the FEPM-based hepatocyte chip could be a useful tool in drug discovery research, including drug metabolism and toxicity studies
Immune Cell Recruitment and Cell-Based System for Cancer Therapy
Immune cells, such as cytotoxic T lymphocytes, natural killer cells, B cells, and dendritic cells, have a central role in cancer immunotherapy. Conventional studies of cancer immunotherapy have focused mainly on the search for an efficient means to prime/activate tumor-associated antigen-specific immunity. A systematic understanding of the molecular basis of the trafficking and biodistribution of immune cells, however, is important for the development of more efficacious cancer immunotherapies. It is well established that the basis and premise of immunotherapy is the accumulation of effective immune cells in tumor tissues. Therefore, it is crucial to control the distribution of immune cells to optimize cancer immunotherapy. Recent characterization of various chemokines and chemokine receptors in the immune system has increased our knowledge of the regulatory mechanisms of the immune response and tolerance based on immune cell localization. Here, we review the immune cell recruitment and cell-based systems that can potentially control the systemic pharmacokinetics of immune cells and, in particular, focus on cell migrating molecules, i.e., chemokines, and their receptors, and their use in cancer immunotherapy
- โฆ