• 한국양식학회지
• /
• 제17권4호
• /
• pp.235-239
• /
• 2004

대하, Fenneropenenaeus chinensis 치하를 대상으로 빈산소, 암모니아 및 황화수소에 대한 장기생존 및 성장에 미치는 영향을 24일간 조사하였다. 2.5 mg/L이하의 용존산소에 노출된 대하 치하는 유의한 성장감소를 나타내었으며 , 3.0 mg/L이하의 농도 에서 일간성장률 및 사료효율이 대조구와 비교하여 유의한 감소를 나타내었다. 암모니아 농도별 노출에 따른 대하의 생존율을 조사한 결과 2.0 mg/L이상의 농도구에서 대조구와 비교하여 생존 감소를 나타내었고, 1.0 mg/L이상 및 0.5 mg/L이상의 암모니아 농도에 노출된 대하 치하는 대조구에 비해 각각 일간성장율 및 사료효율에 영향을 주는 것으로 조사되었다. 또한, 24일간 황화수소에 대한 대하의 생존율은 노출농도와 노출기간이 증가할수록 생존율이 감소하는 경향을 나타내었다. 이러한 경향은 대하 치하의 성장에도 영향을 나타내어 일간성장율과 사료효율이 0.07 mg/L 및 0.05 mg/L 이상의 농도에서 각각 대조구에 비해 유의한 감소가 나타났다.

• 대한수의학회지
• /
• 제40권3호
• /
• pp.497-504
• /
• 2000

To document that effects of hyperbaric oxygen(HBO) and ${\alpha}-tocopherol$ on full-thickness skin grafts in rat, we performed full-thickness skin grafts bilaterally on each rats. The HBO-treated rats were received HBO twice daily for 90 minutes at 2 ATA. Surgical control rats were not treated with HBO. ${\alpha}-tocopherol$ treated rats were received the agent via oral gastric tube daily for 3 days preoperative and a fourth dose 1 to 2 hours postoperative. HBO plus ${\alpha}-tocopherol$ treated rats were received HBO and ${\alpha}-tocopherol$ as mentioned above. Biopsy specimens were taken from each rat at the time of grafting and on days 2, 4, 7, 10, 14, 21, and 28, then were processed for tissue-concentration of total glutathione(GSHt), oxidized/reduced glutathione level, and thiobarbituric acid-reactive substance(TBARS) levels. The percentage of viable graft on day 10 ranged from 67 to 93%, and was not significantly different among the each other groups. The percentage of viable graft were, however, higher in HBO plus ${\alpha}-tocopherol$ treated rats(78.6%) than in HBO alone treated rats(59.1%), ${\alpha}-tocopherol$ alone treated rats(66.7%) and surgical control rats(58.2%). TBARS concentration had a significant increase from preoperative concentration at day 2, and peak concentration at day 4(p<0.01). Concentration then decreased to preoperative concentration at day 28. GSHt concentration of free skin graft had a similar patteren of change in four groups and decreased significantly from preoperative concentration at day 2, returning to preoperative concentration by day 7(surgical control, HBO-treated, and ${\alpha}-tocopherol-treated$, alone) and 28(HBO plus ${\alpha}-tocopherol-treated$). Percentage of the concentration of reduced glutathione decreased in surgical control, HBO-treated and, ${\alpha}-tocopherol-treated$(p<0.05), and HBO plus ${\alpha}-tocopherol-treared$(p<0.01) on day 7 after surgery, whereas the concentration of oxidized increased significantly in HBO-treated(p<0.05), ${\alpha}-tocopherol-treated$(p<0.05), and HBO plus ${\alpha}-tocopherol-treated$(p<0.01).

• 한국식품영양과학회지
• /
• 제31권3호
• /
• pp.500-505
• /
• 2002

뇌조직에서 고혈당으로 인한 산화적 스트레스에 대한 민들레의 유해 활성산소 생성과 제거효소계에 미치는 영향을 알아보고자 streptozotocin으로 당뇨를 유발한 Wistar계 횐쥐에게 민들레의 잎과 뿌리의 분말과 열수추출물을 각각 4주간 급여하였다. 실험결과 유해 활성산소 생성효소계인 시토크롬 P450 함량, aminopyrine N-demethylase, aniline hydroxylase 및 xanthine oxidase 활성은 당뇨를 유발한 대조군에 비하여 서양민들레 잎과 뿌리 급여군 모두 감소되었다. Superoxide dismutase, catalase와 glutathione peroxidase 활성 역시 서양민들레의 분말과 열수추출물 급여시 대조군에 비하여 유의적인 감소를 나타내었으며 민들레의 부위에 따른 차이는 관찰되지 않았다. 반면 뇌조직 중의 glutathione S-transferase 활성과 GSH 함량은 대조군에 비 하여 서양민들레 급여시 유의적으로 증가되었으며, 과산화지질 함량은 당뇨 대조군에 비하여 서양민들레 급여군 모두 유의적인 감소를 보였다. 이상의 결과에서 서양민들레의 잎과 뿌리의 급여는 당뇨로 인한 횐쥐의 뇌조직 중 유리기 생성과 지질과산화로 인한 합병증 예방에 효과적일 것으로 사료된다.

• 제어로봇시스템학회논문지
• /
• 제13권11호
• /
• pp.1128-1136
• /
• 2007

This paper presents an application study of a model predictive control based commercial package PCTP to real chemical processes. The first case study concerns a product purity control of a splitter process which distillates styrene from undesired component ethyl-benzene produced from ethyl-benzene dehydrogenation reaction. The second case study is about a temperature control of ethyl-benzene dehydrogenation reactor and an excess oxygen control of the fired heater. Optimum control structure for MPC application is developed for each case study. The application results show a significant improvement in control performance and stability.

• 한국화재소방학회논문지
• /
• 제30권1호
• /
• pp.1-5
• /
• 2016

최근 심장 혈관 질환 등으로 인한 심정지 발생이 증대됨에 따라, 응급 시 수동 작동 장치나 전기적 구동 장치 없이, 공급 산소의 압력만으로 자동으로 작동되는 휴대용 인공호흡기가 전 세계적으로 보급되고 있다. 그러나 이러한 인공호흡기의 구체적인 압력강하 특성에 대해서는 잘 알려진 바가 없어 본 논문에서는 호흡저항과 관련하여 핵심부품인 유량조절디스크의 다양한 홀 크기에 대한 압력강하 특성을 CFD 시뮬레이션 해석을 통하여 규명하고 압력강하를 최소화할 수 있는 홀 형상의 최적설계 안을 제시하였다.

• 한국환경보건학회지
• /
• 제27권2호
• /
• pp.22-29
• /
• 2001

To evaluate the cutaneous injury in liver damaged rats by toluene application to the skin, toluene(35mg/㎤) was sequentially applied for 5 days to the dorsal skin of liver damaged rats with $CCl_4$ (6 times ever other day:0.1$m\ell$/100 g body weight-50% $CCl_4$in olive oil). The cutaneous ultrastructural changes were unexoectably not observed in liver from $CCl_4$-treated rats although necrotic liver damage appeared under light microscope. In these animals by the application of toluene to rat skin the cutaneous xanthine oxidase activity was significantly increased(p<0.05), but cytochrome P450 content was not different from that of the control or only $CCl_4$-treated rats. On the other hand, the cutaneous superoxide dismutase and catalase activities in liver damaged animals were significantly respectively(p<0.05, p<0.001), decreased by toluene application to the skin compared with control and especially the former enzyme activity was significantty decreased(p<0.01), compared with that of liver damaged rate rat but glutathione peroxidase, glutathione-S-transferase activities were not significantly different from those of the control or liver damaged rats. Futhermore, the reduced gluathione content of skin was also significantly decreased by toluene application to the liver damaged animals. In conclusion, the great deposits of cerrous peroxide and ultramorphological changes in skin tissue of liver damaged animals by toluene application may be responsible for the oxygen free radical.

• 한국잠사곤충학회지
• /
• 제41권3호
• /
• pp.141-146
• /
• 1999

This study was designed to investigate the effects of silkworm powder (SWP) on oxygen radicals and their scavenger enzymes in serum of rats. Sprague Dawley (SD) male rats (160${\pm}$10g) were fed experimental diets (SWP-200and SWP-400 groups)added 200 and 400mg/kg BW/day for 6 weeks. Triglyceride (TG)levels were significantly inhibited (10% and 25%) in SWP-200 and SWP-400 groups, but there were no singificant differences in total, LDL-and HDL-cholesterol levels in both SWP-200 and SWP-400 groups. Hydroxyl radical ($.$OH) formations resulted in a marked decreases (about 20%) in both SWP-200 and SWP-400 groups compared with control group. Superoxide radical (O2.-)and hydrogen peroxide formations resulted in a significant decreases in SWP-400 group compared with control group. Lipid peroxide (LPO)and oxidized protein(>C=O group) productions resulted in a significant decreases (SOD) and catalase (CAT) activiteies were remarkably increased (10∼25% and 40∼50%)in SWP-200 and SWP-400groups. Glutathione peroxidase(GSHPX) activities were significantly increased (about 10%) in SWP-400 groups compared with control group. These results suggest that anti-aging effect of silkworm powder (SWP) may play a pivotal role in attenuation a various chronic degenerative diseases age-related changes.

• 생명과학회지
• /
• 제9권4호
• /
• pp.473-480
• /
• 1999

This study was designed to investigate the effects of pine (Pinus densiflora Sieb et Zucc) needle extract (PNE) on membrane fluidity and oxidative stress in liver membranes of Sprague-Dawley (SD) rats as a study on investigation of anti-aging effect and determination of chemical structures of PNE through the animal experiments. Male SD rats were fed basic diets (control group) and experimental diets (0.5% and 1.0%-PNE group) for 6 weeks. Administrations of 0.5% and 1.0%-PNE resulted in a marked decreases (15∼25% and 23∼26%, respectively) in cholesterol accumulations of liver mitochondria and microsomes compared with control group. Membrane fluidities were significantly increased (15∼25%) in liver microsomes of 0.5% and 1.0%-PNE groups compared with control group. Formations of basal and induced oxygen radicals (BOR and IOR) in liver mitochondria were significantly inhibited (11∼12% and 10∼15%, respectively) by administrations of 0.5% and 1.0%-PNE compared with control group. Lipid peroxide (LPO) levels were remarkbly decreased about 20% in liver mitochondria and microsomes of 0.5% and 1.0%-PNE groups compared with control group. Oxidized protein levels calculated with carbonyl group were significantly decreased about 15% in liver mitochondria of 1.0%-PNE group compared with control group. These results suggest that PNE may play a effective role in a attenuating a oxidative stress and increasing a membrane fluidity.

• 보존과학연구
• /
• 통권34호
• /
• pp.84-99
• /
• 2013

전 세계적으로 분포하고 있는 약 2,900 종의 흰개미 중 23종의 흰개미가 일본에 서식하고 있으며, 이에 따라 1종의 흰개미만 분포하는 우리나라에 비해 더 심각한 피해를 주는 것으로 알려져 있다. 일본에서는 목조건축물에서 흰개미에 의한 피해가 발생하면 화학적 방제(훈증처리, 토양처리, 베이트처리 등)나 비화학적 방제방법(저산소처리, 이산화탄소처리, 고온처리, 저온처리 등)을 이용해 방제처리를 하게 된다. 특히, 훈증처리에 사용되는 메틸 브로마이드 훈증제의 생산과 소비를 2005년부터 전폐하기로 함에 따라 이를 대체하기 위한 다양한 방법들에 대한 검토가 이루어졌으며, 그 결과 실제로 피해 정도가 소규모이거나 장기간의 처리가 가능한 경우 등 일부 경우에는 약제를 사용하지 않는 비화학적 방법이 효과적이라는 것이 확인되었다.

• 생명과학회지
• /
• 제7권4호
• /
• pp.371-376
• /
• 1997

This study was edsigne to investgate the effect of pine needle extract (PNE) on lipid adn oxygen radical metabolisms in serum of Sprague-Dawly (SD). Pine(Pinus densiflora Sieb et Zucc.) is one of the popular plant drugs which gas been used as a medicine in Asia. Male SD rats were fed basic (control group) and experimental diets(RGE group) with 0.5 and 1.0% of PNE for 6 weeks. Body weights gain in 0.5-PNE and 1.0-PNE groups were slightly lower than that in control group, but ther is no significant differences brtween these groups. Total energy intake, feed and gross efficiencies showed almost no change in these groups. Total cholesterol and triglyceride (TG) levels in serumof SD rats in .50-PNE and 0.1-PNE froups sho9wed almost no change colpared with control group. Serum LDL-cholesterol levels significantly decreased (12%) in 0.5-PNE group, while serum HDL-cholesterol levels significantly increased(14%) in 1.0-PNE group compared with control group. Malondialdehyde (MDA) and lipid peroxide (LPO) levels in 50-PNE and 0.1-PNE groups were significantly lower (17 and 13%, 24% and 12%, respectively) than those in control group. Superoxide disumutase (SOD) activity in 50-PNE and 0.1-PNE groups significantly increased about 30 to 15% compared with control group. There results suggest that lower LDL-cholesterol and LPO levels, higher HDL-cholsterol level, and higher SOD activity in serum of rats may be effectively modulated by administration of pine needle extract(PNE).