• 한국식품영양학회지
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• 제13권2호
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• pp.118-124
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• 2000

Lipoxygenase(LOX) in soybeans is responsible for beany flavors which limit the wide utilization of soybeans to foods. This study was conducted to analyze beany flavor compounds of the normal Hwagkeumkong and LOX-deficient soybean cultivars, Jinpumkong which lacks L-2, L-3, and Jinpumkong 2 which lacks all L-1, L-2, L-3. Using the combination of dynamic headspace sampling and gas chromatography-mass selective detector(DHS-GC-MSD) for analyzing volatile compounds, hexanal and hexanol were identified in whole soy flour of all three soybena cultivars. Hwangkeumkong had more volatile compounds than Jinpumkong and Jinpumkong 2 in defatted soy flour. Hexanal and acetic acid were identified in soy milk of all three soybean cultivars but Hwangkeumkong had more volatile compounds than Jinpumkong 2. From the analysis with a static headspace sampling(SHS) and GC-MSD the major compounds were hexanal, acetic acid, 1-hexanol, and 1-octen-3-ol. The content of acetic acid was similar among three cultivars. But contents of hexanal and pentanal in Jinpumkong 2 were less than that of Jinpumkong and Hwangkeumkong. Using GC-FID, Jinpumkong 2 had less contents of hexanal and pentanol than Hwangkeumkong in whole soy flour and defatted soy flour. In this study, LOX-deficient soybean cultivars showed less hexanal, pentanol and other compounds than the normal Hwangkeumkong. However quite amount of beany flavor compounds were identified in Jinpumkong and Jinpumkong 2. So further studies are required to characterize LOX isozymes, to understand the mechanisms of beany flavors production, and to develop some other methods for removing beany flavor.

• Applied Biological Chemistry
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• 제38권5호
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• pp.408-413
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• 1995

Pickle성분이 linolenic acid의 산화효소인 lipoxygenase와 methemoglobin (nonenzymatic oxidant)에 미치는 효과를 조사하였다. 그외, 피클 성분중 건조 양념내의 lipoxygenase, peroxidase와 catalase 활성도 조사하였다. 시중에 판매중인 일부 pickle brine은 lipoxygenase와 methemoglobin에 의한 linolenic acid의 산화를 억제하였다. Dill oil emulsion, 양파 농축액 (onion concentrate), oil cassia, polysorbate 80, turmeric acid와 같은 피클 성분들은 lipoxygenase와 methemoglobin에 의한 산화를 감소시켰다. Lipoxygenase의 활성은 garlic, mustard seed, red pepper에서 발견되었다. Peroxidase의 활성은 mustard seed에서만 존재하였으며, gall black pepper, allspice와 red pepper에서는 catalase의 활성이 있었다.

• 항공우주기술
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• 제1권2호
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• pp.113-122
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• 2002

3단형 과학로켓의 주엔진 추진제의 분사균일성에 대하여 수치해석을 수행하고 설계 개선안을 도출하였다. 분사기 유로는 동일한 압력강하를 가지는 다공성 매질로 처리하였다. 산화제와 연료 모두 공급 유로의 반대쪽에서 분사속도가 높은 것으로 예측되었으며 이는 유동정체에 따른 정압 상승에 기인한다. 산화제 매니폴드 내부의 수직분리판에 유로를 구성함으로써 매니폴드 중심과 외곽에서의 분사균일성을 향상시킬 수 있었다. 산화제 공급유로가 경사를 가지더라도 분사균일성과 압력손실에 미치는 영향은 거의 없었다. 또한 산화제/ 연료에 대한 분사속도로부터 혼합비의 분포를 예측하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.180-185
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• 2004

Our previous study showed that although the hybrid rocket engine with swirling gaseous oxygen had high performance, a direct injection of LOX with swirl into the combustion chamber of the hybrid rocket engine lowered the performance of the engine, compared to that with gaseous oxygen. In order to clarify this reason, combustion tests of a small PMMA combustor with an inner port diameter of 2 mm were conducted in liquid oxygen flow by comparison with gaseous oxygen flow. Although the oxygen mass fluxes of LOX were about two orders of magnitude larger than those of gaseous oxygen, the fuel regression rate of LOX were remarkably smaller than those of gaseous oxygen. For both liquid and gaseous oxygen, diffusion flames in the port of the grain controlled the combustion process of PMMA in oxygen flow. These results may be explained by the fact that only small amount of LOX vaporized and consumed in the combustion with PMMA while flowing through the port due to relatively larger latent heat of injected liquid oxygen compared to the heat of release by combustion which depended on the burning surface area of PMMA.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.77-80
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• 2010

산화제펌프에 대한 수력성능시험을 상온의 물을 매질로 하여 실시하였다. 시험 결과, 산화제펌프는 설계 조건을 만족하였으나, 양정과 효율 모두 상사 법칙을 완전히 만족하지는 않았다. 이 중 양정의 불일치는 고회전수 시험에서의 볼류트 손실 증가 때문으로 보인다. 또한 저유량 영역에서 펌프가 작동할 때에는 누설 유량이 증가하는 것으로 추정되었다.

• 한국해양공학회지
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• 제19권1호
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• pp.20-25
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• 2005

The authors performed the underwater explosion analysis for the liquified oxygen tank - a kind of fuel tank of a mid-size submarine, and tried to verify the structural safety for this structure. First, the authors reviewed the theory and application of underwater explosion analysis, using a Structure-Fluid Interaction technique and its finite element modeling scheme. Next, the authors modeled the explosive and sea water as fluid elements, the LOX tank as structural elements, and the interface between the two regions as the ALE scheme. The effect on shock pressure and impulse of fluid mesh size and shape are also investigated. Upon analysis, it was found that the shock pressure due to explosion propagated into the water region, and hit the structure region. The plastic deformation and the equivalent stress were apparent at the web frame and the shock mount of LOX structure, but these values were acceptable for the design criteria.

• Journal of Crop Science and Biotechnology
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• 제10권2호
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• pp.73-78
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• 2007

The green revolution has significantly helped in increasing the food production. So far, various breeding methods have been exploited, besides them recombination DNA technology provides another approach for increasing the food production. By means of this technology the losses in food production incurred by various biotic and abiotic stresses can be effectively controlled. In most of the transgenic studies scientists have used antibiotic resistant genes as markers for easy selection of transformants but there are risks involved in use of GM foods. To make such foods safer and environment friendly we have discussed a novel strategy i.e. Cre-lox which involves site specific recombination. By means of Cre-lox the marker genes can be specifically removed once the selection of transformants is over. In addition, this strategy can be used to module the hybrid chromosomes, avoid gene silencing and incorporate single copy of a transgene for its higher expression.

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3805-3808
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• 2013

Background: Osteosarcomas have many established risk factors, both genetic and environmental, but by themselves these explain only part of the total cancer incidence. Bisphenol A (BPA) is an environmental estrogen associated with risk of several kinds of tumour. The lysyl oxidase gene (LOX) may also contribute to risk of tumours including osteosarcomas. Here, we investigated possible interactions of BPA and a LOX polymorphism on the risk of osteosarcoma. Method: The present hospital-based case-control study included 106 cancer patients and 112 controls from a Chinese population. Internal burden of BPA exposure was assessed using high-performance liquid chromatography-mass spectrometry (HPLC-MS) method. Genotypes were determined using PCR-RFLP methods. Results: Compared with those in low BPA exposure group, subjects with BPA more than or equal to median value had significant increased risk of osteosarcoma among subjects who carried GC or CC genotypes. A significant interaction with BPA level and the -22G/C polymorphism was observed for osteosarcoma overall, osteosarcoma affecting knee and osteosarcoma affecting hip, as $P_{forinteraction}$ = 0.036 for osteosarcoma overall; $P_{forinteraction}$ = 0.024 for osteosarcoma affecting knee; and $P_{forinteraction}$ = 0.017 for osteosarcoma affecting hip. Conclusions: The results suggest that BPA exposure interacts with the -22G/C polymorphism of the LOX gene to increase the risk of osteosarcoma.

• Asian-Australasian Journal of Animal Sciences
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• 제30권6호
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• pp.886-892
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• 2017

Objective: Transgenic technology is widely used for industrial applications and basic research. Systems that allow for genetic modification play a crucial role in biotechnology for a number of purposes, including the functional analysis of specific genes and the production of exogenous proteins. In this study, we examined and verified the cumate-inducible transgene expression system in chicken DF1 and quail QM7 cells, as well as loxP element-mediated transgene recombination using Cre recombinase in DF1 cells. Methods: After stable transfer of the transgene with piggyBac transposon and transposase, transgene expression was induced by an appropriate concentration of cumate. Additionally, we showed that the transgene can be replaced with additional transgenes by co-transfection with the Cre recombinase expression vector. Results: In the cumate-GFP DF1 and QM7 cells, green fluorescent protein (GFP) expression was repressed in the off state in the absence of cumate, and the GFP transgene expression was successfully induced in the presence of cumate. In the cumate-MyoD DF1 cells, MyoD transgene expression was induced by cumate, and the genes controlled by MyoD were upregulated according to the number of days in culture. Additionally, for the translocation experiments, a stable enhanced green fluorescent protein (eGFP)-expressing DF1 cell line transfected with the loxP66-eGFP-loxP71 vector was established, and DsRed-positive and eGFP-negative cells were observed after 14 days of co-transfection with the DsRed transgene and Cre recombinase indicating that the eGFP transgene was excised, and the DsRed transgene was replaced by Cre recombination. Conclusion: Transgene induction or replacement cassette systems in avian cells can be applied in functional genomics studies of specific genes and adapted further for efficient generation of transgenic poultry to modulate target gene expression.

• 한국추진공학회지
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• 제10권4호
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• pp.1-10
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• 2006

본 논문에서는 극저온 추진제 탱크가 가스 헬륨(GHe) 버블링에 의해 가압될 때 극저온 추진제의 열역학 변수들에 대한 계산 방법을 제시하였다. 헬륨 분사를 이용한 액체 산소(LOX)와 액체 수소($LH_2$) 탱크의 가압 과정에서의 극저온 추진제 온도와 추진제로 용해되는 가스 헬륨의 질량을 분석하였다. 해석 결과를 통해 헬륨 버블링이 LOX와 $LH_2$의 열역학적 변수들에 어떻게 영향을 주는지 확인하였다. 제시된 계산 방법을 통해 가압 시스템으로써 헬륨 버블링의 실현 가능성과 헬륨 버블링을 이용한 가압 시스템의 최적화가 가능할 것이다.