Effects of Sea-Nine 211 and tributyltin on microsomal monooxygenase system of clam, Pseudocardium sachalinensis

Sea-Nine 211 (4,5-dichloro-2-n-octyl-3(2H) isothiazolone) was injected to clam, Pseudocardium sachalinensis, that inhabitate nothern part of Kangwon Province, Korea. Survival rate of the clam and xenobiotics metabolizing enzyme activities in digestive gland were measured during the 4 day-exposure period. The results were compared with those of TBT exposed clam. There were no mortality of clam in the solvent (DMSO) control group and the three Sea-Nine 211 exposure groups (5, 25, 50 mg/kg body weight), while the clam exposed to 1, 2, 5 mg/kg TBT chloride (TBTC) demonstrated 70, 30, 0% survival rate, respectively. The Sea-Nine 211 exposure group showed a tendency of CYP450 induction according to the exposure duration, on the other hand, CYP450 content was decreased in the TBT exposure group. NADPH cytochrome P450 reductase activity slightly increased according to the exposure duration in the Sea-Nine 211 exposure group, while TBTC inhibit its activity as CYP450 content. There was no significant change of cytochrome b5 reductase activity in the clam exposed to Sea-Nine 211. In the TBTC exposure group, its activity increased in early exposure period and then significantly decreased the rest of exposure period. CYP1A1 dependant EROD activities in both the Sea-Nine 211 and the TBTC exposure groups showed no significant differences compared to those of the solvent control group. CYP1A2 dependant MROD activity was significantly induced at the end of exposure, but no significant difference was obtained in the TBTC exposure group. CYP2B1/2 dependant PROD activities in both the Sea-Nine 211 and the TBTC exposure groups showed no significant differences compared to those of the solvent control group. GST activity in the clam exposed to Sea-Nine 211 demonstrated less than those of the solvent control group in the early exposure period, and then recovered at the end of exposure, while its activity was significantly different at the end of exposure in the TBTC exposure1

매엽식 반도체 통합제조장비 시뮬레이터의 동적 실행 방법

학위논문(석사) - 한국과학기술원 : 기계공학전공, 2005.2, [ ix, 78 p. ]Semiconductor manufacturing includes dynamic process variation such as machine failure, hot-run, and an operation time variation. The dynamic process variation is one of major causes of throughput decrease, degradation of wafer quality, and inefficient utilization of raw material. Wafer processing by integrated single-wafer processing tools has become a prevalent manufacturing methodology in recent semiconductor industry. This thesis presents two effective methods that can manage the dynamic process variation of the integrated single-wafer processing tools for performance improvement of the tools, and the presented methods are integrated into the simulator of the tools. One method manages contingency such as machine failure and hot-run. Wafers under processes can be continuously progressed despite of an occurrence of the contingency by this method. The other method manages an operation time variation caused by noise and APC (Advanced Process Control). This method is to regulate a pre-calculated schedule, which makes it possible for the schedule to be executed despite an environment where an operation time varies. The two presented methods are integrated into execution system of the simulator. The execution system of the simulator is a module component that acts such as line-MES (Manufacturing Execution System) in real semiconductor manufacturing. The execution system including the presented methods is evaluated through simulations. Operable wafers under processes are progressed after an occurrence of machine failure and hot-run. A pre-calculated schedule including a schedule from an advanced scheduling algorithm is executed by regulating the schedule, when an operation time varies. The number of a rescheduling decreases considerably. The presented methods that manage dynamic process variation can increase throughput of the tools, quality of wafers, and utilization efficiency of raw material. The improvement of performances is verified through the simulations. ...한국과학기술원 : 기계공학전공