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For plasma window (PW) applications, we developed the cascade arc discharge device with an indirectly heated hollow cathode. The 8-mm channel diameter hollow cathode made of a lanthanum hexaboride (LaB 6) was heated by the C/C composite heater surrounding the cathode to increase the thermionic electron emission. The PW developed successfully separated 2.4 kPa and 16 Pa, and the pressure separation capability was sustained for over 1 h. H- β Stark broadening measurement and the Thomson scattering measurement showed that the electron density and temperature inside the channel reached 10 19 – 10 20 m − 3 and 2.0 eV, respectively. The power balance analysis on the electron thermal energy revealed that the neutral density and temperature inside the channel were as high as 10 23 m − 3 and 4000 K, respectively. The relation between the pressure separation capability and the neutral temperature showed that the flow inside the channel of the PW had the molecular flow feature. The SEM-EDX analysis on the LaB 6 cathode showed that boron diffused to the molybdenum (Mo) shaft during plasma operation, which supported the LaB 6 cathode. Mo shaft became brittle after more than 50 h of operation, exhibiting the necessity of buffer material between the LaB 6 cathode and Mo shaft for long-duration operation. [ABSTRACT FROM AUTHOR]

We developed a steady-state high-density plasma source by applying a hollow cathode to a cascade arc discharge device. The hollow cathode is made of a thermionic material (LaB6) to facilitate plasma production inside it. The cascade arc discharge device with the hollow cathode produced a stationary plasma with an electron density of about 1016 cm−3. It was found that the plasma source produces a strong pressure gradient between the gas feed and the vacuum chamber. The plasma source separated the atmospheric pressure (100 kPa) and a vacuum (100 Pa) when the discharge was performed with an argon gas flow rate of 5.0 l/min and a discharge current of 40 A. An analysis of the pressure gradient along the plasma source showed that the pressure difference between the gas feed and the vacuum chamber can be well described by the Hagen–Poiseuille flow equation, indicating that the viscosity of the neutral gas is the dominant factor for producing this pressure gradient. A potential profile analysis suggested that the plasma was mainly heated within cylindrical channels whose inner diameter was 3 mm. This feature and the results of the pressure ratio analysis indicated that the temperature, and, thus, viscosity, of the neutral gas increased with the increasing number of intermediate electrodes. The discharge characteristics and shape of the hollow cathode are suitable for plasma window applications. [ABSTRACT FROM AUTHOR]

After excluding terminally all patients, we evaluated a total of 718 patients treated with endoscopic injection sclerotherapy. They involved 350 episodes of acute hemorrhage and 368 prophylactic procedures in patients with risky varices. The 1-year cumulative survival rate was significantly lower in the acute hemorrhage group than in the prophylactic group (P < 0.05). The difference in survival between the two groups was primarily due to the number of deaths in the first 2 months after sclerotherapy (20.1% vs 0.8%, P < 0.0005). Improvements in the sclerotherapy technique significantly reduced the number of deaths from bleeding (9.3% vs 3.4%, P < 0.05), but not those from liver failure following variceal hemorrhage. Prophylactic EIS is advantageous in the treatment of esophageal varices, i.e. it may prevent deaths from liver failure attributed to variceal hemorrhages. The present study shows that preliminary prevention of variceal hemorrhage provides favorable hemostatic efficacy in patients with risky varices. [ABSTRACT FROM AUTHOR]

To understand better the thermal decomposition characteristics of organic peroxides, a C80 heat flux calorimeter was used and the decomposition pattern of cumene hydroperoxide and di- tert-butylperoxide were classified as auto-catalytic and n th order reaction, respectively. Based on the scanning results with the C80 at several differing rates of heating, the thermal decomposition behavior of organic peroxides under isothermal storage at lower temperature was simulated with a model-free simulation. Simulated results showed that the calculated conversion of cumene hydroperoxide as a function of time was in good agreement with experimental data obtained with the TAM-III high sensitivity thermal activity monitor. [ABSTRACT FROM AUTHOR]

Kampo (Japanese traditional herbal) medicines have been produced by combining multiple crude drugs, almost all of plant origin but with some of animal or mineral origin, and contain a great many substances. Their effect is a combination of the various interactions of the constituent substances, whether they are enhancing, synergistic or suppressive. Kampo medicine has an overall effect that is different from the combined effects of individual crude drugs, and several side effects such as anorexia, slight fever and nausea have been reported in the treatment of certain disorders and disease states with Kampo medicines. Among 210 medical formulations used in Japan, some relevant information on the clinical uses, pharmacology and toxicology of six manufactured Kampo medical formulations, Shosaikoto, Daisaikoto, Saikokeishito, Hochuekkito, Saibokuto and Saireito, containing Bupleurum root are reviewed. Studies of some potential interactions between Kampo medicine and western drugs are also considered. [ABSTRACT FROM AUTHOR]