• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.4
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• pp.241-248
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• 2008

The purpose of the research is to investigate of diesel spray combustion for simultaneously reduction way of NOx and PM. The diesel injection were done into intermediates that are generated by very lean DME HCCI combustion using a RCM. The concentration of intermediate could not be directly measured, so we estimated it by CHEMKIN calculation. Two dimensional spontaneous luminescence images which are created by chemical species reaction at low temperature reaction (LTR) and high temperature reaction (HTR) are captured by using a framing streak camera. Also, combustion events were observed by high-speed direct photography. The ignition and combustion events were analyzed by pressure profiles and the KL values and flame temperatures were analyzed by the two-color method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1119-1125
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• 2004

The effect of hemicellulose extracted from soy fiber on the level of blood glucose and serum cholesterol in the streptozotocin-induced diabetic rat were investigated. The experimental plots were divided to cellulose group (control, 0.5％ hemicellulose group (H-l) and 1％ hemicellulose group (H-2) group. The groups were fed for 6 weeks, then fed for 1 week more after streptozotocin injection. Food intakes, weight gain and food efficiency ratio of H-2 group were higher, while water intakes and liver weight were lower than those of control and H-l group. The content of blood glucose and urine glucose were 212.8 mg/dL, 0.97 mg/dL in the control group, 160.5 mg/dL, 0.53 mg/dL in the H-l group, 141.0 mg/dL, 0.35 mg/dL in the H-2 group, respectively. There was no significantly difference in the content of neutral lipid, while the content of total serum cholesterol was 101.6 mg/dL in the control group, 73.8-78.4 mg/dL in the hemicellulose groups. The content of serum HDL-cholesterol in the all experimental groups showed no significantly difference showing 39.8-44.7 mg/dL. HTR and atherogenic index were 0.44 and 1.27 in the control group, but 0.54 and 0.46-0.85 in the hemicellulose groups, respectively.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.375-382
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• 2019

Abnormalities of trophoblast due to early inflammation in pregnancy increase the expression of CRP and affect maternal-fetal interactions, leading to preterm birth and preeclampsia. However, biomarkers related to the regulation of CRP expression have not been found. In this study, miRNA associated with increased expression of CRP was identified and their expression was analyzed to reveal biomarkers involved in the regulation mechanism of trophoblast inflammation through miRNAs. miRNAs that were predicted to regulate CRP gene expression in miRNA databases (mirna, TargetScan, MicroCosm) were screened and HTR-8/SVneo cell lines were treated with LPS (20 ng/mL) to induce inflammatory responses in vitro, with selected miR-7, miR-150, miR-186 and miR-424. The expression was analyzed by qRT-PCR. As a result, expression of CRP was significantly increased in LPS-treated trophoblast (p<0.001) and miR-150 and miR-424 expression were significantly decreased (p<0.001). Thus, miR-150 and miR-424 are involved in the regulation of CRP expression in inflammatory-induced trophoblast and may be useful for the prenatal diagnosis of inflammatory obstetric diseases.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.893-899
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• 2009

Few studies have reported the existence of imprinted genes in cattle compared to the human and mouse. Genomic imprinting is expressed in monoallelic form and it depends on a single parent-specific form of the allele. Comparative analysis of mammals other than the human is a valuable tool for explaining the genomic basis of imprinted genes. In this study, we investigated 34 common imprinted genes in the human and mouse as well as 35 known non-imprinted genes in the human. We found short interspersed nuclear elements (SINEs), long interspersed nuclear elements (LINEs), and long terminal repeats (LTRs) in imprinted (human and mouse) and control (cattle) genes. Pair-wise comparisons for the three species were conducted using SINEs, LINEs, and LTRs. We also calculated 95% confidence intervals of frequencies of repetitive sequences for the three species. As a result, most genes had a similar interval between species. We found 11 genes with conserved SINEs, LINEs, and LTRs in the human, mouse, and cattle. In conclusion, eleven genes (CALCR, Grb10, HTR2A, KCNK9, Kcnq1, MEST, OSBPL5, PPP1R9A, Sgce, SLC22A18, and UBE3A) were identified as candidate imprinted genes in cattle.

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.73-82
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• 2008

This study was done to investigate the antidiabetic and antioxidant effects of Lycii fructus in Streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by intravenous injection of STZ at a dose 45mg/kg.b.w. dissolved in citrate buffer(pH4.5). The ethanol extract of Lycii fructus was orally administrated once a day for 7 days. The contents of serum glucose, total cholesterol were significantly decreaed (p<0.05) in Lycii fructus treated group compared to the those of STZ-control group, also content of Triglyceride (TG), Altherogenic index (AI) were decreased, but not statistically significant. But high density lipoprotein (HDL)-cholesterol and HDL-cholesterol/total cholesterol ratio (HTR) were increased in Lycii fructus treated group compared to the those of STZ-control group. The content of hepatic glycogen and activities of glucose-6-phosphate dehydrogenase(G-6PDH), glutathione-s-transferase(GST), superoxide dismutase(SOD) were significantly increased(p<0.05), glucose-6-phos-phatase(G-6pase)was significantly decreased(p<0.05) and The glutathione(GSH), glucokinase(GK) were increased. But not statistically significant In Lycii fructus treated group compared to the those of STZ-control group These results indicated that ethanol extract of Lycii fructus would have antidiabetic and antioxidant effects in STZ-induced diabetic rats.

• Journal of the Korean Applied Science and Technology
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• v.22 no.2
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• pp.157-167
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• 2005

The extraction yield of Corni fructus was about 47.5% by extract apparatus. This study was done to investigate the antidiabetic and antioxidative effects of Corni fructus in Streptozotocin (STZ)-induced diabetic rats. The contents of serum glucose, total cholesterol and hepatic lipid peroxide, glutathione were significantly decreaed (p<0.05) in Corni fructus treated group compared to the those of STZ-control group, also content of triglyceride (TG), atherogenic index (AI) and activity of catalase were decreased, but not statistically significant. High density lipoprotein (HDL)-cholesterol and HDL-cholesterol/total cholesterol ratio (HTR) were increased in Corni fructus treated group compared to the those of STZ-control group. The activities of glutathione-S-transferase (GST) and superoxide dismutase (SOD) were significantly decreaed (p<0.05) in Corni fructus treated group compared to the those of STZ-control group. The content of hepatic glycogen and activities of glucose-phosphate dehydrogenase (G-6 PDH), glucokin-ase were significantly increased, but activity of glucose-Grphosphatase (G-6 Pase)was decreased in Corni fructus treated group compared to the those of STZ-control group. Therefore, these results indicated that ethanol extract of Corni fructus would have antidiabetic and antioxidative effects in STZ-induced diabetic rats.

• Journal of the Korean Applied Science and Technology
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• v.21 no.3
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• pp.204-213
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• 2004

Extraction of Sedum sarmentosum Bunge by super critical carbon dioxide was operated under $40-50^{\circ}C$and 200-250 atm, thus, yield of extraction was very low as 4 wt%. Rats were administrated with the extract orally once a day for succesive 6 days, followed by treatment with carbon tetrachloride ($CCl_4$) on the sixth day. The activities of aminotransferase, alkaline phosphatase, ${\gamma}$-glutamyl transpeptidase, lactate dehydrogenase and contents of triglyceride, total cholesterol in the extract-pretreated rats were decreased compared to the $CCl_4$controled rats, whereas content of HDL-cholesterol was increased. Especially content of hepatic malondialdehyde (MDA) and atherogenic index (AI) were decreased and HTR was increased in the extract-pretreated rats, and reduced peroxidative liver damage in the $CCl_4$-induced hepatotoxicity rats. In addition, activities of hepatic superoxide dismutase, catalase, glutathione peroxidase in the extract-pretreated rats were significantly decreased compared to the $CCl_4$ controled rats, but the content of glutathione was significantly increased. These results suggest that extract of Sedum sarmentosum Bunge has hepatoprotective effect in the $CCl_4$-intoxicated rats.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.357-373
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• 2022

The high-temperature gas-cooled reactor pebble-bed module project is the first commercial Generation-IV NPP(Nuclear Power Plant) in China. A new joint is used for the vertical support of RPV(Reactor Pressure Vessel). The steel corbel is integrally embedded into the reactor-cabin wall through eight asymmetrically arranged pre-stressed high-strength bolts, achieving the different path transmission of shear force and moment. The vertical monotonic loading test of two specimens is conducted. The results show that the failure mode of the joint is bolt fracture. There is no prominent yield stage in the whole loading process. The stress of bolts is linearly distributed along the height of corbel at initial loading. As the load increases, the height of neutral axis of bolts gradually decreases. The upper and lower edges of the wall opening contact the corbel plate to restrict the rotation of the corbel. During the loading, the pre-stress of some bolts decreases. The increase of the pre-stress strength ratio of bolts has no noticeable effect on the structure stiffness, but it reduces the ultimate bearing capacity of the joint. A simplified calculation model for the elastic stage of the joint is established, and the estimation results are in good agreement with the experimental results.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.2840-2851
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• 2022

Electric boilers (EBs) are the backup steam source for the auxiliary steam system of high-temperature gas-cooled reactor nuclear power plants. When the plant is in normal operations, the EB is always in hot standby status. However, the current hot standby operation strategy has problems of slow response, high power consumption, and long operation time. To solve these problems, this study focuses on the optimization of hot standby operations for the EB system. First, mathematical models of an electrode immersion EB and its accompanying deaerator were established. Then, a control simulation platform of the EB system was developed in MATLAB/Simulink implementing the established mathematical models and corresponding control systems. Finally, two optimization strategies for the EB hot standby operation were proposed, followed by dynamic simulations of the EB system transient from hot standby to normal operations. The results indicate that the proposed optimization strategies can significantly speed up the transient response of the EB system from hot standby to normal operations and reduce the power consumption in hot standby operations, improving the dynamic performance and economy of the system.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.933-940
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• 2024

A macroscopic cross section generation model was developed for the conceptual horizontal, compact high temperature gas reactor (HC-HTGR). Because there are many sources of spectral effects in the design and analysis of the core, conventional LWR methods have limitations for accurate simulation of the HC-HTGR using a neutron diffusion core neutronics simulator. Several super-cell model configurations were investigated to consider the spectral effect of neighboring cells. A new history variable was introduced for the existing library format to more accurately account for the history effect from neighboring nodes and reactivity control drums. The macroscopic cross section library was validated through comparison with cross sections generated using full core Monte Carlo models and single cell cross section for both 3D core steady-state problems and 2D and 3D depletion problems. Core calculations were then performed with the AGREE HTR neutronics and thermal-fluid core simulator using super-cell cross sections. With the new history variable, the super-cell cross sections were in good agreement with the full core cross sections even for problems with significant spectrum change during fuel shuffling and depletion.