• 제목/요약/키워드: GGH

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침적 입자를 고려한 탈황설비용 GGH 판넬 요소의 유동해석 (Fluid Analysis of GGH Panel Elements considering Deposition Particles for Desulfurizing Equipments)

  • 류봉조;김종호;김후식;이강수;구경완
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.601-605
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    • 2009
  • The paper deals with the proper design of GGH(gas-gas heater) panel elements of desulfurization equipments in a thermoelectric power plant. When fossil fuels such as coal, petroleum et cetera are burnt to ashes, sulfur oxide compounds are produced, and calcareous sludges are deposited at GGH panel elements. In this case, operation of a power plant equipments is interrupted, and a tremendous economic loss comes into existence. One of the purposes of the paper is to find flow velocity distributions and regions of depositions when calcareous sludges pile up on the GGH panel elements through the fluid analysis. In the fluid analysis, flow velocity and position distributions of particles between GGH panel elements are demonstrated according to time variation for ammonia and calcium hydroxide particles.

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고지방식이 마우스 비만모델에서 감비경신환(減肥輕身丸)(2)에 의한 혈중 중성지방 농도와 내장지방의 변화 (Gambigyeongsinhwan(2) Reduces Blood Triglyceride Levels and Improves Visceral Fat in High Fat Diet-Fed Obese Male C57BL/6N Mice)

  • 신순식;이희영;이혜림;윤미정;이용태
    • 대한한의학방제학회지
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    • 제19권2호
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    • pp.47-59
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    • 2011
  • Objectives : We investigated the effects of gambigyeongsinhwan2(GGH(2)) on body weight and examined whether blood triglyceride levels and visceral fat are inhibited by it in high fat diet-fed obese male mice. Methods : 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(2)-1, GGH(2)-2 and GGH(2)-3. After mice were treated with GGH(2) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Results : 1. Compared with controls, GGH(2)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(2)-3. 2. Compared with controls, GGH(2)-treated mice had lower feeding efficiency ratio, the magnitude of which was prominent in GGH(2)-3. 3. Compared with controls, GGH(2)-treated mice had lower blood plasma triglyceride level. 4. Blood plasma AST and ALT concentrations were not changed by GGH(2), indicating GGH(2) do not show any toxic effects. 5. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(2), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(2) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(2). Conclusions : These results demonstrate that GGH(2) effectively reduces body weight gain, feeding efficiency ratio, blood plasma triglyceride level and improves abdominal fat.

감비경신환(1)에 의한 고지방식이 비만동물모델에서 체중감량과 지질대사의 조절 (Gambigyeongsinhwan(1) Improves Body Weight and Lipid Metabolism in High Fat Diet-Fed Obese Animal Model)

  • 신순식;윤미정;총배금;이용태
    • 대한본초학회지
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    • 제29권1호
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    • pp.35-43
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    • 2014
  • Objectives : We investigated the effects of gambigyeongsinhwan(GGH)(1) on body weight and non-alcoholic fatty liver disease(NAFLD) examined whether blood total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels and hepatic lipid accumulation are inhibited by it in high fat diet-fed obese male mice. Methods : 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(1)-1, GGH(1)-2 and GGH(1)-3. After mice were treated with GGH(1) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma ALT, leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Results : Compared with controls, GGH(1)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(1)-3. Compared with controls, GGH(1)-treated mice had lower feeding efficiency ratio and blood leptin level, the magnitudes of which was prominent in GGH(1)-3. Compared with controls, GGH(1)-treated mice had lower blood plasma total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels. Compared with controls, GGH(1)-3 treated mice had lower blood plasma ALT concentration. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(1), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(1) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(1). Conclusions : In conclusion, these results suggest that GGH(1) exhibits anti-obesity effects through the modulation of feeding efficiency ratio and plasma obesity parameters. Moreover, it seems that GGH(1) also contributes to improve NAFLD through the regulation of plasma ALT and hepatic triglyceride accumulation.

[논문철회]고지방식이 마우스 비만모델에서 감비경신환(4)에 의한 체중감량과 간 지방축적의 변화 ([Retracted]Gambigyeongsinhwan(4) Reduces Body Weight and Hepatic Lipid Accumulation in High Fat Diet-Fed Obese Male C57BL/6N Mice)

  • 이혜림;안예지;이희영;이형희;김동여;윤미정;이용태;신순식
    • 동의생리병리학회지
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    • 제27권1호
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    • pp.99-106
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    • 2013
  • We investigated the effects of gambigyeongsinhwan(GGH)(4) on body weight and non-alcoholic fatty liver disease(NAFLD) examined whether blood total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels and hepatic lipid accumulation are inhibited by it in high fat diet-fed obese male mice. 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(4)-1, GGH(4)-2 and GGH(4)-3. After mice were treated with GGH(4) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma ALT, leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Compared with controls, GGH(4)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower feeding efficiency ratio and blood leptin level, the magnitudes of which was prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower blood plasma total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels. Compared with controls, GGH(4)-2 treated mice had lower blood plasma ALT concentration. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(4), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(4) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(4). In conclusion, these results suggest that GGH(4) exhibits anti-obesity effects through the modulation of feeding efficiency ratio and plasma obesity parameters. Moreover, it seems that GGH(4) also contributes to improve NAFLD through the regulation of plasma ALT and hepatic triglyceride accumulation.

침적 입자를 고려한 유동해석을 통한 신형 탈황설비용 GGH 요소 최적화 (Optimization of the Gas-Gas Heater Element for Desulfurization Equipment through Fluid Analysis of considering Deposition Particles)

  • 오부진;류봉조;이영신;김종호;백수곤
    • 한국소음진동공학회논문집
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    • 제20권7호
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    • pp.611-619
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    • 2010
  • The paper deals with the proper design of GGH(gas-gas heater) panel elements of desulfurization equipments in a thermoelectric power plant. When fossil fuels such as coal, petroleum et cetera are burnt to ashes, sulfur oxide compounds are produced, and calcareous sludges are deposited at GGH panel elements. In this case, operation of a power plant equipments is interrupted, and a tremendous economic loss comes into existence. One of the purposes of the paper is to find flow velocity distributions and regions of depositions when calcareous sludges pile up on the GGH panel elements through the fluid analysis. In the fluid analysis, flow velocity and position distributions of particles between GGH panel elements are demonstrated according to time variation for ammonia and calcium hydroxide particles.

Enzymes involved in folate metabolism and its implication for cancer treatment

  • Kim, Sung-Eun
    • Nutrition Research and Practice
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    • 제14권2호
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    • pp.95-101
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    • 2020
  • BACKGROUND/OBJECTIVES: Folate plays a critical role in DNA synthesis and methylation. Intracellular folate homeostasis is maintained by the enzymes folylpolyglutamate synthase (FPGS) and γ-glutamyl hydrolase (GGH). FPGS adds glutamate residues to folate upon its entry into the cell through a process known as polyglutamylation to enhance folate retention in the cell and to maintain a steady supply of utilizable folate derivatives for folate-dependent enzyme reactions. Thereafter, GGH catalyzes the hydrolysis of polyglutamylated folate into monoglutamylated folate, which can subsequently be exported from the cell. The objective of this review is to summarize the scientific evidence available on the effects of intracellular folate homeostasis-associated enzymes on cancer chemotherapy. METHODS: This review discusses the effects of FPGS and GGH on chemosensitivity to cancer chemotherapeutic agents such as antifolates, such as methotrexate, and 5-fluorouracil. RESULTS AND DISCUSSION: Polyglutamylated (anti)folates are better substrates for intracellular folate-dependent enzymes and retained for longer within cells. In addition to polyglutamylation of (anti)folates, FPGS and GGH modulate intracellular folate concentrations, which are an important determinant of chemosensitivity of cancer cells toward chemotherapeutic agents. Therefore, FPGS and GGH affect chemosensitivity to antifolates and 5-fluorouracil by altering intracellular retention status of antifolates and folate cofactors such as 5,10-methylenetetrahydrofolate, subsequently influencing the cytotoxic effects of 5-fluorouracil, respectively. Generally, high FPGS and/or low GGH activity is associated with increased chemosensitivity of cancer cells to methotrexate and 5-fluorouracil, while low FPGS and/or high GGH activity seems to correspond to resistance to these drugs. Further preclinical and clinical studies elucidating the pharmocogenetic ramifications of these enzyme-induced changes are warranted to provide a framework for developing rational, effective, safe, and customized chemotherapeutic practices.

Goldreich-Goldwasser-Halevi 전자서명의 선택 평문 공격 (Chosen Message Attack Against Goldreich-Goldwasser-Halevi's Lattice Based Signature Scheme)

  • DaeHun Nyang
    • 정보보호학회논문지
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    • 제14권1호
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    • pp.47-57
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    • 2004
  • 이 논문에서는 Crypto97에 발표된 잘 알려진 lattice 문제에 기반한 Goldreich-Goldwasser-Halevi(GGH)의 전자 서명을 암호 해독한다. GGH의 서명방법에 선택 평문공격을 수행하고 제안하는 공격방법에 취약함을 보인다. 암호 해독한다. GGH의 서명방법에 선택 평문공격을 수행하고 제안하는 공격방법에 취약함을 보인다. 암호해독 방법에서는 서로 선형 독립적인 n개의 lattice점을 모아서 원래 lattice의 sub-lattice를 생성하는 새로운 basis를 생성한다. 이 sub-lattice가 유효한 서명을 생성하는데 사용될 수 있음을 보인다. 이 공격방법의 유효성을 실험을 통해서 보이고, 마지막으로 비밀키를 생성하는데 사용되는 cube-like parameter가 안정성에 좋지 않은 영향을 미침을 보인다.

석탄화력 탈황설비 Non-leakage Type Gas-Gas Heater(GGH) 운영 및 개선사례 (Operation and Improvement Cases of FGD Non-leakage Type Gas-Gas Heater(GGH) for Coal Fired Power Plants)

  • 성기종;이창식
    • 한국연소학회지
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    • 제22권4호
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    • pp.35-42
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    • 2017
  • This case covers the issues related to the operation problem, cause analysis and improvement cases of the FGD that employed the non-leakage type GGH in coal-fired power plant for the first time in Korea. In the Cooler, there was a main problem that the tube is damaged by the ash cutting due to the high velocity of flue gas in the duct and by the weak wear resistance of material. In the Reheater, there was a main problem that the tube was corroded due to chlorine and sulfur in the circumstance of the low temperature. In order to solve those problems, we have improved the Reheater tube and tube fins by coating enamel to reduce corrosion rate.

Association Between Polymorphisms of Dihydrofolate Reductase and Gamma Glutamyl Hydrolase Genes and Toxicity of High Dose Methotrexate in Children with Acute Lymphoblastic Leukemia

  • Koomdee, Napatrupron;Hongeng, Suradej;Apibal, Suntaree;Pakakasama, Samart
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권7호
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    • pp.3461-3464
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    • 2012
  • Methotrexate (MTX) is an important drug for the treatment of childhood acute lymphoblastic leukemia (ALL). However, related toxicity occurs in many organs which may cause interruption of treatment, morbidity, and mortality. Single nucleotide polymorphisms (SNPs) of dihydrofolate reductase (DHFR) and gamma glutamyl hydrolase (GGH) are known to alter their enzymatic activity and thus affect the metabolism of MTX and influence the effectiveness. Therefore, we hypothesized that genetic variations of DHFR and GGH genes may influence the risk of toxicity after high dose MTX. The study population comprised of 105 children with ALL who were treated according to the modified St Jude Total XV protocol. The patients received 2.5 or $5g/m^2$ of MTX for 5 doses during the consolidation phase. Genotyping of DHFR 829C>T and GGH-401C>T was performed using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The GGH-401CT and TT genotypes were associated with increased risk of leukopenia and thrombocytopenia after high dose MTX (OR 2.97, 95%CI; 1.24-7.13 and OR 4.02, 95%CI; 1.58-10.26). DHFR 829C>T was not associated with toxicity. In conclusion, the GGH-401CT and TT genotypes were found to increase the risk of severe leukopenia and thrombocytopenia after exposure to high dose MTX for childhood ALL therapy.

습식 배연탈황공정에서 GGH 누설률 평가식의 수정 (Modification of GGH Leakage Evaluation Equations in Wet FGD System)

  • 천성남;안영모;장경룡
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2003년도 춘계학술대회 논문집
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    • pp.387-388
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    • 2003
  • 습식 배연탈황 공정에서는 흡수탑 내에서의 황산화물 흡수율을 높일 목적으로 흡수탑으로 유입되는 배기가스를 약 5$0^{\circ}C$까지 냉각하고, 처리된 배기가스는 연돌에서의 자연 통풍력을 확보하고 연돌 배출 후 수분의 응축으로 인한 백연(white Plume)의 문제를 방지하고자 통상 9$0^{\circ}C$ 이상으로 가온하는 것이 일반적이며 이를 위해 다양한 형식의 열교환기가 설치 운영되고 있다. 탈황공정에서 흔히 GGH(gas to gas heater)라 불리는 Ljungstrom 방식의 열 교환기는 미처리된 고온가스와 처리된 저온 가스가 회전하는 열교환소자로 이루어진 영역을 지나면서 열 교환이 이루어지는 형태로 회전 부위 및 두 가스흐름의 구분 판(sector plate) 등에서 필연적으로 처리가스 흐름 중으로 미처리 가스의 누입이 일어나게 된다. (중략)

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