RESUMO
A thermal ion driven bursting instability with rapid frequency chirping, considered as an Alfvénic ion temperature gradient mode, has been observed in plasmas having reactor-relevant temperature in the DIII-D tokamak. The modes are excited over a wide spatial range from macroscopic device size to microturbulence size and the perturbation energy propagates across multiple spatial scales. The radial mode structure is able to expand from local to global in â¼0.1 ms and it causes magnetic topology changes in the plasma edge, which can lead to a minor disruption event. Since the mode is typically observed in the high ion temperature â³10 keV and high-ß plasma regime, the manifestation of the mode in future reactors should be studied with development of mitigation strategies, if needed. This is the first observation of destabilization of the Alfvén continuum caused by the compressibility of ions with reactor-relevant ion temperature.
RESUMO
A Multi-Color (MC) gas puff imaging diagnostic has been developed on HL-2A tokamak. This diagnostic can simultaneously measure two-dimensional (2D, radial, and poloidal) electron density and temperature distributions with a good spatial resolution of 2.5 × 2.5 mm2 and a temporal resolution of about 100 µs at best in edge plasmas. The 2D electron density and temperature distributions are inferred from the ratios of intensities of three different neutral helium emission lines; therefore, it is also referred to as helium beam probe or beam emission spectroscopy on thermal helium. A compact light splitter is used to split the inlet visible emission beam into four channels, and the specific neutral helium lines of the wavelengths λ1 = 587.6 nm, λ2 = 667.8 nm, λ3 = 706.5 nm, and λ4 = 728.1 nm are measured, respectively. This MC diagnostic has been experimentally tested and calibrated on a linear magnetic confinement device Peking University Plasma Test device, and the measured 2D electron density and temperature distributions are compared with the Langmuir probe measurements.
RESUMO
OBJECTIVE: To identify the factors influencing the prognosis of patients with acute pulmonary embolism(PE) and to establish a prognostic model. METHODS: The clinical data of 331 patients (141 males and 190 females, aged 9 to 87 years ) with acute PE in Fujian Hospital from January 2007 to September 2013 were analyzed. Univariate analysis and logistic regression analysis were used for selecting the independent prognostic factors for acute PE. Based on logistic regression analysis, a prognostic model for PE was established. RESULTS: Univariate analysis showed that statistically significant (all P<0.05) factors influencing the prognosis of PE were diabetes, tricuspid systolic murmur, body temperature, respiratory rate, heart rate, aspartate aminotransferase, triglycerides, abnormal ECG, mechanical ventilation, circulatory failure during hospitalization, risk stratification of PE, types of treatment, and use of low-molecular-weight heparin and Warfarin. Logistic regression analysis showed that recent (<1 month) operation or fracture, tricuspid systolic murmur, high triglyceride level, circulatory failure during hospitalization and mechanical ventilation were independent factors for poor prognosis of PE, while combined use of low-molecular-weight heparin and Warfarin was a protective factor for the prognosis of PE. The Fisher prognostic model equation was y=0.144+ 1.266x1+ 0.869x2+ 1.794x3-0.517x4+ 3.555x5+ 0.661x6. The accuracy of the Fisher discriminant function was 93.0%. CONCLUSION: Recent (<1 month) operation or fracture, tricuspid systolic murmur, high triglyceride level, shock during hospitalization and mechanical ventilation were signs of poor prognosis for PE, while combined use of low-molecular-weight heparin and Warfarin were beneficial for the prognosis. The discriminant function based on these data can be helpful for predicting the prognosis of patients with PE.
