• The Korean Journal of Food And Nutrition
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• v.13 no.2
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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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• v.38 no.5
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• pp.408-413
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• 1995

Investigations of the effects of pickle product ingredients on lipoxygenase (LOX) and methemoglobin (MHG, a nonenzymatic oxidant) catalyzing oxidation of linolenic acid were conducted. In addition, activities of LOX, peroxidase (POD) and catalase (CAT) in dry spices used in pickle products were determined. Some commercial pickle brines were observed to inhibit oxidation of linolenic acid by LOX and MHG. The ingredients in pickle products, such as dill oil emulsion, onion concentrate, oil cassia, polysorbate 80 and turmeric acid, reduced LOX and MHG catalyzed oxidation. Lipoxygenase activity was present in garlic, mustard seed and red pepper. Only in mustard seed, peroxidase activity was observed. Catalase activity was observed in garlic, black pepper, allspice and red pepper.

• Aerospace Engineering and Technology
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• v.1 no.2
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• pp.113-122
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• 2002

A numerical analysis on the uniformity of propellant injection velocity of KSR-III has been carried out to give design improvements. Injector holes were approximated as porous media with the same pressure drop . The injection velocity is higher at the opposite side of the inlet for both LOX and fuel due to the static pressure rise in the stagnation region. Flow passages at the vertical circular plate in the LOX dome increase the uniformity of LOX injection. Little change was observed in the injection uniformity and pressure drop for the slanted LOX passage. Also provided were the O/ F ratio distributions from the oxidizer/ fuel injection velocity analysis.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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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.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.77-80
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• 2010

A series of hydraulic tests of a Lox pump are performed using water at a room temperature. According to the test results, the Lox pump satisfies its design requirement but both the head and the efficiency do not fully follow the conventional similarity rule. The deviation of the head from the rule is assumed to be due to the increased volute loss at high rotational speed. Furthermore, it is found that when the pump rotates with the flow ratio less then the design requirement the leakage flowrate seems to be increased.

• Journal of Ocean Engineering and Technology
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• v.19 no.1 s.62
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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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• v.10 no.2
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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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• v.14 no.6
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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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• v.30 no.6
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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.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.4
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• pp.1-10
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• 2006

In this paper, a calculation method of the thermodynamic parameters of cryogenic propellant is proposed when a cryogenic propellant tank is pressurized by gaseous helium(GHe) bubbling. Temperature of cryogenic propellant and mass of dissolved GHe into propellant were analyzed at the various operation of pressurization of tile liquid oxygen(LOX) and hydrogen($LH_2$) tank using helium bubbling. It was evaluated how the GHe bubbling influences to the thermodynamic parameters of LOX and $LH_2$ with results of the analysis. With the proposed calculation method, It will be able to confirm the feasibility of GHe bubbling as a pressurization system of cryogenic propellant tank and to optimize the pressurization system using GHe bubbling.