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Several gas injection systems such as fueling, massive gas injection (MGI), supersonic molecular beam injection (SMBI) have been installed for the Korea Superconducting Tokamak Advanced Research (KSTAR). Piezoelectric valves with a built-in piezoelectric plate of disc-bender type were used for the precise feedback control of gas flow. The relationship between the displacement and blocking force of the piezoelectric plates is taken into account in designing and fabricating piezoelectric valves. The MGI system was installed for the mitigation of plasma disruption. The MGI valve is composed of two-volume chamber. The valve is equipped with an aluminum piston and an actuator coil of inductance 0.1 mH. The power supply unit using a capacitor discharge method has been developed in order to drive the MGI valve. The SMBI system consisting of LN2 cooling line, pulse valve, and its controller was operated for the mitigation of edge localized mode (ELM). The LN2 cooling line is used to increase the density of the injected gas. The status and specification of each gas injection system is presented and the operational characteristics are analyzed.

A series of azo disperse dyes having dicyanovinyl groups was synthesized by the Knoevenagel condensation with malononitrile from carbonyl substituted phenylazo disperse dyes which were prepared by conventional diazo coupling reaction of aniline derivatives as diazo components. A variety of coupling components such as anilines, an indole and a pyridone were used. The azo disperse dyes were evaluated for their spectral properties and dyeing assessment on the polyester fabrics. The azo disperse dyes containing dicyanovinyl groups showed bathochromic shifts and darker colors due to increased electron withdrawing strength in their azo components and extended conjugation by dicyanovinyl groups than their parent carbonyl substituted azo dyes. The dyes containing 2-acetylamino-5-methoxy substituent in the coupling component exhibited higher wavelength of maximum absorbance (λmax) and significant negative solvatochromism than those of other dyes due to intramolecular hydrogen bonding.

Objective : This study aims to visualize the subjective symptoms before and after the treatment of whiplash injury using infrared (IR) thermography. Methods : IR thermography was performed for 42 patients who were diagnosed with whiplash injury. There were 19 male and 23 female patients. The mean age was 43.12 years. Thermal differences (∆T) in the neck and shoulder and changes in the thermal differences (∆dT) before and after treatment were analyzed. Pain after injury was evaluated using visual analogue scale (VAS) before and after treatment (∆VAS). The correlations between ∆dT and ∆VAS results before and after the treatment were examined. We used Digital Infrared Thermal Imaging equipment of Dorex company for IR thermography. Results : The skin temperature of the neck and shoulder immediately after injury showed 1–2°C hyperthermia than normal. After two weeks, the skin temperature was normal range. ∆T after immediately injuy was higher than normal value, but it was gradually near the normal value after two weeks. ∆dT before and after treatment were statistically significant ( p

5-Funtionalized enantiomerically pure oxazolidin-2-ones were prepared in one pot from commercially available chiral aziridines bearing an electron-withdrawing group at C-2 with retention of the configuration in high yields by regioselective aziridine ring-opening followed by intramolecular cyclization.

Objective : This study aimed to determine the optimal time for tracheostomy by evaluating the benefits and safety of early versus late tracheostomy in spinal cord injury (SCI) patients. Methods : We retrospectively reviewed a total of 254 patients with spinal cord injury. Of them, we selected 21 spinal cord injury patients who required tracheostomy due to long-term mechanical ventilation and analyzed their medical records. The patients were categorized into two groups. Early tracheostomy was performed day 1-10 from intubation in 10 patients and the late tracheostomy was performed after day 10 in 11 cases. We also evaluated the duration of mechanical ventilation, stay in the ICU and complications related to tracheostomy, the injury level of and clinical severity. All data was analyzed using SPSS 18.0/WIN. Results : The early tracheostomy offered clear advantages for shortening the total ICU stay (20.8 day vs. 38.0 day, p=0.010). There was also statistically significant reduction in the total length of time on mechanical ventilation (5.2 day vs. 29.2 day, p=0.009). However, the reductions in the incidence of pneumonia (40% vs. 82%) and the length of ICU stay post to tracheostomy (6 day vs. 15 day) were found to be statistically not signifi cant. There were also no statistically significant differences in the injury level and clinical severity between the groups. Conclusion : We concluded that the early tracheostomy (at least 10 days) is beneficial for SCI patients who are likely to require prolonged mechani cal ventilation.