• Title/Summary/Keyword: 활성화시간

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Field Tests for Assessing the Bioremediation Feasibility of a Trichloroethylene-Contaminated Aquifer (관측정 자연표류 실험을 통한 트리클로로에틸렌(Trichloroethylene) 오염 지하수의 생물학적 복원 타당성 연구)

  • Kim Young;Kim Jin-Wook;Ha Chul-Yoon;Kim Nam-Hee;Hong Kwang-Pyo;Kwon Soo-Yul;Ahn Young-Ho;Ha Joon-Su;Park Hoo-Won
    • Journal of Soil and Groundwater Environment
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    • v.10 no.3
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    • pp.38-45
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    • 2005
  • The feasibility of stimulating in situ aerobic cometabolic activity of indigenous microorganisms was investigated in a trichloroethylene (TCE)-contaminated aquifer. A series of single-well natural drift tests (SWNDTs) was conducted by injecting site groundwater amended with a bromide tracer and combinations of toluene, oxygen, nitrate, ethylene and TCE into an existing monitoring well and by sampling the same well over time. Three field tests, Push-pull Transport Test, Drift Biostimulation Test, and Drift Surrogate Activity Test, were performed in sequence. Initial rate of toluene degradation was much faster than the rate of bromide dilution resulting from natural groundwater drift, indicating stimulation of indigenous toluene-oxidizing microorganisms. Transformation of ethylene, a surrogate probing overall activity of TCE transformation, was also observed, and its transformation results in the production of ethylene oxide, suggesting that some tolueneoxidizing microorganisms stimulated may express a orthomonooxygenase enzyme. Also in situ transformation of TCE was confirmed by greater retardation of TCE than bromide after the stimulation of toluene-oxidizing microorganisms. These results indicate that, in this environment, toluene and oxygen additions stimulated the growth and aerobic cometabolic activity of indigenous microorganisms expressing orthomonooxygenase enzymes. The simple, low-cost field test method presented in this study provides an effective method for conducting rapid field assessments and pilot testing of aerobic cometabolism, which has previously hindered application of this technology to groundwater remediation.

Doses of Coronary Study in 64 Channel Multi-Detector Computed Tomography : Reduced Radiation Dose According to Varity of Examnination Protocols (64 채널 Multi-Detector Computed Tomography를 이용한 관상동맥검사의 선량 : 검사 프로토콜 다변화에 따른 환자선량 감소)

  • Kim, Moon-Chan
    • Journal of radiological science and technology
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    • v.32 no.3
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    • pp.299-306
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    • 2009
  • Purpose : To compare radiation dose for coronary CT angiography (CTA) obtained with 6 examination protocols such as a retrospectively ECG gated helical scan, a prospectively ECG gated sequential scan, low kVp technique, and cardiac dose modulation technique. Materials and Methods : Coronary CTA was performed by using 6 current clinical protocols to evaluate effective dose and organ dose in primary beam area with anthropomorphic female phantom and glass dosimetric system in 64 channel multi-detector CT. After acquiring topograms of frontal and lateral projection with 80 kVp and 10 mA, main coronary scan was done with 0.35 sec tube rotation time, 40 mm collimation ($0.625\;mm{\times}64\;ea$), small scan field of view (32 cm diameter), 105 mm scan length. Heart beat rate of phantom was maintained 60 bpm in ECG gating. In constant mAs technique 120 kVp, 600 mA was used, and 100 kVp for low kVp technique. In a retrospectively ECG gated helical CT technique 0.22 pitch was used, peak mA (600 mA) was adopted in range of $40{\sim}80%$ of R-R interval and 120mA(80% reduction) in others with cardiac dose modulation. And 210 mAs was used without cardiac dose modulation. In a prospectively ECG gated sequential CT technique data were acquired at 75% R-R interval (middle diastolic phase in cardiac cycle), and 120 msec additional padding of the tube-on time was used. For effective dose calculation region specific conversion factor of dose length product in thorax was used, which was recommended by EUR 16262. Results : The mean effective dose for conventional coronary CTA without cardiac dose modulation in a retrospectively ECG gated helical scan was 17.8 mSv, and mean organ dose of heart was 103.8 mGy. With low kVp and cardiac dose modulation the mean effective dose showed 54.5% reduction, and heart dose showed 52.3% reduction, compared with that of conventional coronary CTA. And at the sequential scan(SnapShot pulse mode) under prospective ECG gating the mean effective dose was 4.9 mSv, this represents an 72.5% reduction compared with that of conventional coronary CTA. And heart dose was 33.8 mGy, this represents 67.4% reduction. In the sequential scan technique under prospective ECG gating with low kVp the mean effective dose was 3.0 mSv, this represents an 83.2% reduction compared with that of conventional coronary CTA. And heart dose was 17.7 mGy, this represents an 82.9% reduction. Conclusion : In coronary CTA at retrospectively ECG gated helical scan, cardiac dose modulation technique using low kVp reduced dose to 50% above compared with the conventional helical scan. And the prospectively ECG gated sequential scan offers substantially reduced dose compared with the traditional retrospectively ECG gated helical scan.

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Study on the Improvement of Gill Nets and Trap Nets Fishing for the Resource Management at the Coastal Area of Yellow Sea - On the Entrapping Behavior of Fishes into Trap Nets in the Water Tank Experiment - (서해구 자원관리형 자망ㆍ통발 어구어법 기술개발에 관한 연구 - 수조에서의 통발에 대한 어군의 입롱행동 -)

  • 장호영;조봉곤;고광수;한민숙
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.1
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    • pp.56-62
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    • 2003
  • To investigate the entrapping behavior of blue crab, rock shell and green ling, which are mainly caught with the other trap nets in the coastal area of Yellow Sea, by the using duration of trap nets through the water tank experiment. We select the three kinds of trap nets which have different using duration such as new, 6 months and 12 months used one, and observe the entrapping ratio into the trap nets, respectively. In the mean while, in order to obtain the basic data for the estimate of mesh selectivity of the other trap nets, the entrapping behavior into the trap nets for green ling which has high activity compared to blue crab and rock shell, are examined to the three kinds of mesh size (35mm, 50mm and 65mm). The results are as follows ; 1. The mean entrapping ratio of blue crab by the using duration of trap nets in high with 4.4 fishes (44.0%) in the 6 months used one, become lower with 2.9 fishes (28.0%) in the new one, and with 2.0 fishes (20.0%) in the 12 months used one. 2. The mean entrapping ratio of rock shell by the using duration of trap nets in high with 7.3 fishes (36.7%) in the new one, and become lower with 7.2 fishes (35.8%) in the 6 months used one, and with 5.7 fishes (28.3%) in the 12 months used one. 3. The mean entrapping ratio of green ling by the using duration of trap nets in high with 3.4 fishes (34.0%) in the 6 months used one, and become lower with 3.0 fishes (30.0%) in the new one, and with 2.8 fishes (28.0%) in the 12 months used one. 4. The mean residual ratio of green ling by the mesh size of trap nets is high with 2.4 fishes (24.0%) in the 35mm mesh size, and become lower with 2.2 fishes (22.0%) in the 50mm mesh size and 2.0 fishes (20.0%) in the 65mm mesh size.

국제 수학 올림피아드 참가 후보자들을 위한 상황대처훈련에 관한연구

  • 김보경;조성희;이군현
    • Proceedings of the Korean Society for the Gifted Conference
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    • 1994.08a
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    • pp.1.2-37
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    • 1994
  • Currently Korea encourages gifted high schoolers and junior high schoolers to participate in international achievement contests such as International Olympiads. Participants for these contests are selected nationwide among gifted students in areas of mathematics, physics, chemistry, and others. They go through a series of screening tests and programs. One of the screening processes IS Korean Olympiad School, which provides study programs each summer for student-candidates prior to following year's International Olympiads. Approximately 40 students of high schools and junior high schools, in each subject of study, gather at Korean Olympiad Summer School, and they go through intensive study programs during a short period of time. Out of 40 candidates,' less than 10 students are finally selected to participate in International Olympiads. In this study, a psycho-educational program called "Situation Coping Training Program" was developed to enhance ahievement motivation for these student-candidates. This study was to see if this training program actually improved their cognitive, emotive motivation factors, and to see how this training program affected their achievement level. Training was administered for five days. This training program was found effective for participants to increase self-efficacy, internal locus of control, and anxiety copmg. These cognitive and emotive motivation factors, other than intelligence, were found to have positive relationship with achievement level, of which self-efficacy and attribution style of students were found as two best predictors of achievement. This training program was perceived as necessary. by participants, and helpful for recovering self-confidence and self-control as well as coping pressure. Suggestions were made that this kind of training program be administered as a regular curriculum in preparative study programs such as Korean Olympiads, since cognitive, emotive motivation factors are related with achievement, and furthermore, be utilized in all gifted education programs in Korea. in Korea.

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Development of Black Garlic Yakju and Its Antioxidant Activity (흑마늘 발효주 개발 및 항산화 활성)

  • Lee, Hyo-Hyung;Kim, Ig-Jo;Kang, Sang-Tae;Kim, Yeong-Hoon;Lee, Jeong-Ok;Ryu, Chung-Ho
    • Korean Journal of Food Science and Technology
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    • v.42 no.1
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    • pp.69-74
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    • 2010
  • Black garlic has recently received significant attention due to its various health functional properties, and there has been an increase in demand for its use as a functional food. This study was performed to determine the optimum concentration for the fermentation of black garlic yakju. In addition, the antioxidant activity of the fermented black garlic yakju was examined. The alcohol content in the black garlic yakju significantly increased for 6 days and the pH gradually increased as the concentration of black garlic increased. The reducing sugar content at each black garlic concentration was maximal when it was fermented for 24 hours, and then rapidly decreased at longer fermentation periods. The main organic acids were lactic, citric, malic and oxalic acid. Also, the lactic acid content increased as the concentration of the black garlic increased where as the content of other organic acids decreased. The total polyphenol content, ferric ion reducing antioxidant power (FRAP) activity and DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging activity of black garlic yakju increased as the concentration of black garlic increased. The sensory characteristics of fermented black garlic yakju were evaluated in terms of color, flavor, taste and overall acceptability, and the highest overall acceptability value was obtained for yakju containing a black garlic concentration of 1-3%. Therefore, the optimum concentration of black garlic was determined to be 1% for the production of high quality black garlic yakju.

Evaluation of Macrophage Activity and Repeated Oral Dose Toxicity in Sprague-Dawley Rats on Multivitamin (종합비타민의 랫드에서 반복투여독성 시험과 대식세포 기능 활성 평가)

  • Kim, Hye-Ri;Jang, Hye-Yeon;Lee, Hae-Nim;Park, Young-Seok;Park, Byung-Kwon;Kim, Byeong-Soo;Kim, Sang-Ki;Cho, Sung-Dae;Nam, Jeong-Seok;Choi, Chang-Sun;Chang, Soon-Hyuk;Jung, Ji-Youn
    • Journal of Food Hygiene and Safety
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    • v.28 no.4
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    • pp.360-366
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    • 2013
  • The objective of this study is to investigate the effect of multivitamin on macrophage activity in Raw 264.7 cell and repeated oral dose toxicity in Sprague-Dawely rat of multivitamin. Raw 264.7 cells were treated with 50 and $100{\mu}g/mL$ multivitamin for 24 h. To measure the activity of macrophages, NO and TNF-${\alpha}$ assays were performed in Raw 264.7 cells. Treatment with 50 and $100{\mu}g/mL$ multivitamin for 24 h significantly increased production of NO and TNF-${\alpha}$ compared with control groups, indicating activation of macrophages. The female rats were treated with multivitamin of control group, low group (0.24 g/kg), medium group (1 g/kg) and high group (2 g/kg) intragastrically for 4 weeks, respectively. We examined the body weight, the feed intake, the clinical signs and serum biochemical analysis. We also observed the histopathological changes of liver, ovary, brain, adrenal gland, spleen, kidney, heart and lung in rats. No significant differences in body weights, feed intake, biochemical analysis and histopathological observations between control and multivitamin treatment group were found. In conclusion, multivitamin is physiologically safe and improve macrophage activity.

4-Hydroxynonenal Induces Endothelial Cell Apoptosis via ROS and Peroxynitrite Generation (4-Hydroxynonenal에 생성된 ROS와 peroxynitrite를 통한 내피세포의 세포사에 관한 연구)

  • Chung, Sang-Woon;Yee, Su-Bog;Lee, Ji-Young;Hossain, Mohammad Akbar;Kim, Dong-Hwan;Yoon, Jeong-Hyun;Chung, Hae-Young;Kim, Nam-Deuk;Kim, Nam-Deuk
    • Journal of Life Science
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    • v.21 no.7
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    • pp.961-968
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    • 2011
  • The formation of reactive lipid aldehydes, 4-hydroxynonenal (HNE) is shown to be derived from fatty acid hydroperoxides through the oxidative process. Among its known effects in cytotoxicity, HNE has been implicated in apoptotic cell death. To delineate its putative role as a potential mediator, we investigated the mechanism by which HNE induces apoptosis of endothelial cells (ECs). The anti-proliferative effects of HNE were tested through MTT assay after exposure to various concentrations ($5\sim15\;{\mu}M$) of HNE. We observed apoptotic bodies with propidium iodide staining, and measured the HNE induction of endothelial apoptosis by flow cytometry assay. We observed that cells exposed to HNE for 24 hr resulted in increased poly(ADP-ribose) polymerase cleavage and up-regulation of Bax. Data on the HNE action strongly indicated the involvement of reactive species, namely, intracellular ROS, nitrite, and peroxynitrite. To obtain evidence on the implication of ROS and peroxynitrite in HNE-induced apoptosis, a ROS scavenger, N-acetylcysteine (NAC), and a peroxynitrite scavenger, penicillamine, were tested. Results clearly indicate that the induction of apoptosis by HNE was effectively inhibited by NAC and penicillamine. Based on the present data, we conclude that the endothelial apoptosis induced by HNE involves both ROS generation and peroxynitrite activity. Our new data could lead to a redefinition of HNE action on apoptosis in ECs.

Effect of Treadmill Exercise Training on the Expression of PGC-1α, GLUT-1, Tfam Proteins and Antioxydent Ezymes in Brain of STZ-Induced Diabetic Rats (트레드밀 지구성 운동이 streptozotocin으로 유발된 당뇨 흰쥐의 뇌에서 PGC-1α, GLUT-1, Tfam 단백질 및 항산화 효소(Cu, Zn-SOD, Mn-SOD)의 발현량에 미치는 영향)

  • Park, Noh-Hwan;Lee, Jin;Jung, Kook-Hyun;Choi, Bong-Am;Jang, Hyung-Chae;Lee, Suk-In;Lee, Dong-Soo;Cho, Joon-Yong
    • Journal of Life Science
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    • v.21 no.3
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    • pp.435-443
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    • 2011
  • The purpose of this study is to identify the effects of exercise training [ET, 10~18 m/min (speed), 20~30 min (exercise duration)/a day for 5 day/wk, 6 wk) on PGC-$1{\alpha}$, GLUT-1, Tfam, Cu,Zn-SOD and Mn-SOD proteins in brain of STZ-induced diabetic rats. The male Sprague-Dawley (SD) rats were single-injected intraperitoneally with 50mg/kg of streptozotocin (STZ) to produce STZ-induced diabetic rats. Rats were divided into 3 experimental groups with 8 rats in each group, as follows: (1) non-STZ group (n=8), (2) STZ-CON group (n=8), (3) STZ-EXE group (n=8). The results of this study suggest that i) serum glucose level was significantly reduced in STZ-EXE group compared with STZ-CON group (p<0.05), ii) PGC-$1{\alpha}$ (p<0.001), mtPGC-$1{\alpha}$ (p<0.001), GLUT-1 (p<0.001), and mtTfam (p<0.001) proteins in brain of STZ-induced diabetic rats were significantly increased in STZ-EXE group compared with STZ-CON group, iii) Cu,Zn-SOD (p<0.001) and Mn-SOD (p<0.01) proteins in the STZ-induced diabetic rats were significantly increased in STZ-EXE group compared with STZ-CON group. In conclusion, the findings of the present study reveal that treadmill exercise training increases brain GLUT-1 protein level possibly through up-regulation of PGC-$1{\alpha}$ and Tfam proteins which represent key regulatory components of stimulation of brain mitochondrial biogenesis. In addition, treadmill exercise training may prevent oxidative stress by up-regulation of Cu,Zn-SOD and Mn-SOD proteins in the STZ-induced diabetic rats.

Effect of Internal Organs of Todarodes pacificus Extracts on Blood Rheological Properties and Serum Lipid Concentration (오징어 부산물이 혈액 유동성 및 혈중 지질 농도에 미치는 영향)

  • Kang, Sung-Rim;Lee, Sang-Hyeon;Bae, Song-Ja;Park, Mi-Ra;Park, Joung-Hyun;Kim, Mi-Hyang
    • Journal of Life Science
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    • v.20 no.1
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    • pp.90-96
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    • 2010
  • Menopause increases the onset of hypertension and heart disease. Whereas it increases the blood LDL-cholesterol, triglyceride and total-cholesterol levels, the HDL-cholesterol concentration is reduced. Accordingly, we examined the effect of internal organs of Todarodes pacificus (IOT) on improvement in blood flow ability and changes in serum lipid content by using ovariectomized rats. For this study, the following four groups of 9-week-old Sprague-Dawley strain female rats were evaluated over 6 weeks: normal rats (SHAM), ovariectomized rats (CON) and ovariectomized rats that were treated with IOT extracts. Ovary removal promoted platelet aggregability. However, IOT administration in the CON group after ovary excision resulted in a hinderance of coherence. The blood vessel passing time of ovariectomized rats was slower than the SHAM group. But the blood flow ability, which was slowed down for ovary removal, was improved by IOT administration. Serum triglyceride levels were significantly reduced by IOT administration. Moreover, blood HDL-cholesterol levels were reduced by ovary removal. However, IOT administration after ovary excision significantly increase HDL-cholesterol levels. The biological activity of IOT could be confirmed from these results. Moreover, IOT can be used in the development of functional foods which are meant to improve blood circulation and anti-platelet aggregation function. According to these results, we could know that IOT improved blood flow and anti-platelet aggregation. Therefore, it is expected that IOT can be used for the development of functional foods.

Rheological Properties of ${\beta}-Glucan$ Isolated from Non-waxy and Waxy Barley (메성 및 찰성보리 ${\beta}-Glucan$의 리올로지 특성)

  • Choi, Hee-Don;Park, Yong-Gon;Jang, Eun-Hee;Seog, Ho-Moon;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.32 no.3
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    • pp.590-597
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    • 2000
  • The rheological properties of ${\beta}-glucans$ isolated from non-waxy and waxy barley were investigated. ${\beta}-Glucan$ solutions showed pseudoplastic properties and their behaviors were explained by applying Power law model in the range of concentrations$(1{\sim}4%)$ and temperatures$(20{\sim}65^{\circ}C)$. The effects of temperature and concentration on the apparent viscosity at $700\;s^{-1}$ shear rate were examined by applying Arrhenius equation and power law equation, and their effect was more pronounced in waxy ${\beta}-glucan$ solutions. The activation energy for flow of ${\beta}-glucan$ solutions decreased with the increase of concentration, and the concentration-dependent constant A increased with the increase of temperature. The intrinsic viscosity of waxy ${\beta}-glucan$ was higher than that of non-waxy ${\beta}-glucan$. The transition from dilute to concentrate region occurred at a critical coil overlap parameter $C^*[{\eta}]=0.02.$ The slopes of non-waxy and waxy ${\beta}-glucan$ at $C[{\eta}] were similar, but the slope of waxy ${\beta}-glucan$ at $C[{\eta}]>C^*[{\eta}]$ was higher than that of non-waxy ${\beta}-glucan$. Dynamic viscoelasticity measurement showed that cross-over happened, and storage modulus was higher than loss modulus at frequency range above cross-over. ${\beta}-Glucan$ solutions formed weak gels after stored for 24 hr.

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