• Journal of Life Science
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• v.28 no.1
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• pp.78-82
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• 2018

Detection of pathogenic microorganisms takes several days by conventional methods. It is necessary to assess microorganisms in a timely manner to reduce the risk of spreading infection. For this purpose, bacteriophages are chosen for use as a biosensing tool due to their host specificity, wide abundance, and safety. However, their lytic cycle limits their efficacy as biosensors. Phage proteins involved in binding to bacteria could be a robust alternative in resolving this drawback. Here, a fragment of tail protein J (residues 784 to 1,132) of phage lambda fused with 6X His-tag (6HN-J) at its N-terminus was cloned, overexpressed, purified, and characterized for its binding with microorganisms. The purified protein demonstrated a size of about 38 kDa in sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) and bound with anti-His monoclonal antibodies. It bound specifically to Escherichia coli K-12, and not Salmonella typhimurium, Bacillus subtilis, or Pseudomonas aeruginosa in dot blotting. Binding of the protein to E. coli K-12 inhibited about 50% of the in vivo adsorption of the phage lambda to host cells at a concentration of $1{\mu}g/ml$ 6HN-J protein and almost 100% at $25{\mu}g/ml$ 6HN-J. The results suggest that a fusion viral protein could be utilized as a biosensing element (e.g., protein chips) for detecting microorganisms in real time.

• Journal of Life Science
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• v.30 no.10
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• pp.835-843
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• 2020

Obesity, the world's leading metabolic disease, is a serious health problem in both industrialized and developing countries. Natural substances are of great interest in preventative medicine, especially in the field of metabolic syndromes-from insulin resistance to obesity and diabetes. In the present study, we investigated the effect of A. pullulans SM-2001 Extract (Polycan^®) on the adipocyte differentiation of 3T3-L1 preadipocytes and the anti-obesity effect of 3T3-L1 adipocytes. Although β-glucan has been found to have health benefits in the regulation of the immune system and blood cholesterol levels, its role in obesity has not been fully investigated. Polycan^® suppressed lipid accumulation and glycerol-3-phosphate dehydrogenase (GPDH) activity without affecting cell viability in 3T3-L1 preadipocytes and adipocytes. Polycan^® also inhibited cellular lipid accumulation through down-regulation of transcription factors, such as PPARγ and C/EBPα, and induced dose-dependent phosphorylation of AMP-activated protein kinase (AMPK)-a cellular energy sensor-while the total AMPK protein content remained unchanged. Taken together, this shows that the activation of AMPK by Polycan^® in adipocytes plays a critical role in Polycan^®-induced inhibition of adipocyte differentiation. Our results show that Polycan^® has an anti-obesity action in vitro, suggesting a potential novel preventative agent for obesity and other metabolic diseases.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.7
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• pp.929-933
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• 2010

Four-point bending tests were performed to investigate the interfacial adhesion of Cu-Cu bonding fabricated by thermo-compression process for three dimensional packaging. A pair of Cu-coated Si wafers was bonded under a pressure of 15 kN at $350^{\circ}C$ for 1 h, followed by post annealing at $350^{\circ}C$ for 1 h. The bonded wafers were diced into $30\;mm\;{\times}\;3\;mm$ pieces for the test. Each specimen had a $400-{\mu}m$-deep notch along the center. An optical inspection module was installed in the testing apparatus to observe crack initiation at the notch and crack propagation over the weak interface. The tests were performed under a fixed loading speed, and the corresponding load was measured. The measured interfacial adhesion energy of the Cu-to-Cu bonding was $9.75\;J/m^2$, and the delaminated interfaces were analyzed after the test. The surface analysis shows that the delamination occurred in the interface between $SiO_2$ and Ti.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.196-196
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• 2017

Oilseed crop Camelina (Camelina sativa L.) is a suitable for biodiesel production that has high adaptability under low-nutrient condition like marginal land and requires low-input cost for cultivation. Enhanced abiotic stress tolerance of Camelina is very important for oil production under the wide range of different climate. CsRCI2s (Rare Cold Inducible 2) are related proteins in various abiotic stresses that predicted to localized at plasma membrane (PM) and endoplasmic reticulum (ER). These proteins are consist of eight-family that can be divided into tail (CsRCI2D/E/F/G) and no-tail (CsRCI2A/B/E/H) type of C-terminal. However, it is still less understood the function of C-terminal tail. In this study, CsRCI2D/H genes were cloned through gateway cloning system that used pCB302-3 as destination vector. And we used agrobacterium-mediated transformation system for generation of overexpression (OX) transformants. Overexpression of target gene was confirmed using RT-PCR and segregation ratio on selection media. We analyzed physiological response in media and soil under abiotic stresses using CsRCI2D and CsRCI2H overexpression plant. To compare abiotic stresses tolerance, wild type and CsRCI2D/H OX line seeds were sown on agar plate treated with various NaCl and mannitol concentration for 7 days. In the test of growth rate under abiotic stress on media, CsRCI2H OX line showed similar to NaCl and mannitol stress. In the other hand, CsRCI2D OX line showed to be improved stress tolerance that especially increased in 200mM NaCl but was similar on mannitol media. In greenhouse, WT and CsRCI2D/H OX lines for physiological analysis and productivity under abiotic stresses were treated 100, 150, 200mM NaCl. Then it was measured various parameters such as leaf width and length, plant height, total seed weight, flower number, seed number. CsRCI2H OX line in greenhouse did not show any changes in physiological parameters but CsRCI2D OX line was improved both physiological response and productivity under NaCl stress. Among physiological parameters of CsRCI2D OX line under NaCl stress, leaf length and width were observed shorter than WT but it were slightly longer than WT in 200mM NaCl stress. Furthermore, total seed weight of CsRCI2D OX line under stress displayed to decrease than WT in normal condition, but it was gradually raised with increasing NaCl stress then more than WT relatively. These results suggested CsRCI2D might be contribute to improve abiotic stress tolerance. However, function of CsRCI2H is need to more detail study. In conclusion, overexpression of CsRCI2s family can generate various environmental stress tolerance plant and may improve crop productivity for bio-energy production.

• Korean Journal of Environmental Agriculture
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• v.26 no.1
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• pp.1-6
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• 2007

In view of energy supply, biogas can be seen as alternative fuel by substituting considerable amount of fossil fuel and may be utilized for heat and power production or for transport fuel production ($CH_4-enriched$ biogas). The aim of this research is to analyse the emission of $NO_x$ and CO from biogas fired combustion engine for electric power production. The result indicate a significant effect of biogas composition ($CH_4-CO_2$ ratio) and biogas flow rate on the air pollutants emission. The emission factors from this study were compared with those of U.S. EPA. Low $CH_4-CO_2$ ratio condition typically shows the lower $NO_x$ and CO emission than higher $CH_4-CO_2$ ratio condition. At normal $CH_4-CO_2$ ratio (7:3) emission factors of $NO_x$ and CO were 1.29 and 30.43 g/MMBtu, respectively. At low $CH_4-CO_2$, ratio (6:4) emission factors of $NO_x$ and CO were 0.646 and 60.86 g/MMBtu, respectively, It should be emphasized that the actual emission may vary considerably from these results due to operating conditions including torque load and engine speed.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1339-1347
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• 2003

An experiment was conducted to investigate the effects of microbial phytase ($Natuphos^{(R)}$) supplementation in combination with carbohydrases (composed of enzymes targeted to soybean meal (SBM) dietary components such as $\alpha$-galactosides and galactomannans; $Endo-Power^{(R)}$) to corn-soybean meal based diet (CSD) and complex diet (CD) with a partial replacement of SBM with rape seed meal (RSM) and cotton seed meal (CSM) on growth performance and nutrient digestibility of growing pigs. A total of 168 growing pigs averaging $13.18{\pm}1.77kg$ of initial body weight was arranged as a $2{\times}2$ factorial design with main effects of diet types (corn-SBM based diet (CSD) and complex diets (CD; 5% of SBM was replaced with 2.5% of RSM and 2.5% of CSM in diet for phase I (0 to 3 weeks) and 6% of SBM was replaced with 3% of RSM and 3% of CSM in diet for phase II (4 to 7 weeks))) and enzyme supplementation (none and 0.1% of phytase (500 FTU/kg diet) and 0.1% of carbohydrases). The diet with enzyme application were formulated to have a 0.18% unit lower aP than diets without enzyme application. Each treatment had three replicates with 14 pigs per replicate. To determine supplementation effect of phytase and carbohydrases on ileal amino acid digestibility of SBM, RSM and CSM, a total of 18 T-cannulated pigs (initial body weight; $13.52{\pm}1.24kg$) were assigned to six dietary treatments in the present study. Dietary treatments in metabolic trial included 1) SBM diet, 2) SBM diet+with enzymes (phytase (500 FTU/kg) and carbohydrases at 0.1%, respectively), 3) CSM diet, 4) CSM diet+enzymes, 5) RSM diet and 6) RSM diet+enzymes. During whole experimental period (0 to 7 wks), there was no difference in growth performance between diets (CSD and CD). However, dietary phytase and carbohydrases supplementation significantly improved gain/feed ratio (G:F) of growing pigs. During the phase II (4-7 weeks), dietary phytase and carbohydrases supplementation significantly improved all fecal nutrient digestibilities (Dry matter (DM), gross energy (GE), crude protein (CP), crude fat (CF), calcium (Ca) and phosphorus (P)). Dietary phytase and carbohydrases supplementation improved significantly overall ileal amino acid digestibilities of SBM, RSM and CSM based diets (p<0.05). The simultaneous inclusion of phytase and carbohydrases in both of CSD and CD reduced feed cost per kg body weight gain (FCG). Also, results suggest that 2.5 to 3% of RSM and CSM, respectively, might be used as a protein source in growing pig diets without having an adverse effect on the growth performance and nutrient digestibility and simultaneous phytase and carbohydrases addition improves nutritional value of SBM, RSM and CSM by improving ileal amino acid digestibilities.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1729-1735
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• 2004

A total of 140 weaning pigs were used to determine the effects of digestive enzyme supplementation to corn-soybean meal diets on growth performance, physiological changes of small intestine, microorganisms and pH in the gastrointestinal tract. Two kinds of enzyme complex (A, B) were used in this experiment. Pigs were allotted in a completely random design (CRD) to five replicates with four pigs per pen. Diets and water were provided for ad libitum consumption. Treatments included 1) Control: without enzyme supplementation, 2) Enzyme A 0.05%, 3) Enzyme A 0.10%, 4) Enzyme A 0.15%, 5) Enzyme B 0.05%, 6) Enzyme B 0.10%, 7) Enzyme B 0.15% in the diets. A total of 24 crossbred barrows 25.78${\pm}$0.55 kg BW fitted with simple ileal T-cannulas were used to evaluate the effect the enzyme addition on the nutrient digstibility. Pigs were allotted 4 treatments (No enzyme, enzyme A 0.05%, enzyme A 0.1%, enzyme A 0.15%), 6 replicates according to a completely random design (CRD). Another digestibility trial was followed for enzyme complex B. Twenty pigs, average 31.92${\pm}$0.37 kg BW, fitted with simple ileal T-cannulas for digestibility trial. Neither enzyme A nor enzyme B affected on fecal or ileal digestibility of dry matter, gross energy, crude protein, crude fat and crude ash (p>0.05). The apparent fecal digestibilities of all the nutrients were higher in total feces collection method than in indirect method. At the end of feeding trial, 21 pigs were slaughtered for examining the morphological changes of small intestine and the concentration of microorganisms in the ileum and the colon. Growth performance, intestinal morphology and pH of ileum and colon were not affected by the either enzyme complex supplementation (p>0.05). These results suggested that enzyme complex A and enzyme complex B were of no benefit to early-weaned pigs when corn-soybean meal based diet was provided.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.23-30
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• 2016

In this study, the heat transfer and pressure drop characteristics were evaluated for multi-tube $CO_2$ water heaters with lengths of 4.5 m and 7.5 m. The evaluation was done using the -NTU method, and the results were compared with experimental data. Water flows through the shell side of the water heater, while $CO_2$ flows through 8 inner tubes. The heater uses a counter-current design to maximize the heat transfer efficiency. The energy balance equation describing the flows of $CO_2$ and water for each node is set up using the section-by-section method. The calculated heat transfer rates agree well with the experimental data within ${\pm}5%$ error. The outlet water temperature decreased linearly with the increase of the water flow rate. The calculated heat transfer rates agreed well with the experimental data within ${\pm}3%$ error. The results show that the heat transfer rate increases almost linearly with the increase of water flow rate or $CO_2$ inlet temperature in both the 4.5-m and 7.5-m water heaters, whereas the water outlet temperature linearly decreases with the increase of the water flow rate. The comparison of the $CO_2$ pressure drop between the calculation and experiment results shows good agreement at the high $CO_2$ flow rate within 5 % error, but the value is about 20 % higher in the experimental pressure drop at the low $CO_2$ flow rate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.596-601
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• 2020

Silicon carbide is considered a potentially useful material for high-temperature electronic devices because of its large band gap energy and p-type or n-type conduction that can be controlled by impurity doping. Accordingly, the thermoelectric properties of -SiC powder prepared by refined diatomite were investigated for high value-added applications of natural diatomite. -SiC powder was synthesized by a carbothermal reduction of the SiO₂ in refined diatomite using carbon black. An acid-treatment process was then performed to eliminate the remaining impurities (Fe, Ca, etc.). n-Type semiconductors were fabricated by sintering the pressed powder at 2000℃ for 1~5h in an N2 atmosphere. The electrical conductivity increased with increasing sintering time, which might be due to an increase in carrier concentration and improvement in grain-to-grain connectivity. The carrier compensation effect caused by the remaining acceptor impurities (Al, etc.) in the obtained -SiC had a deleterious influence on the electrical conductivity. The absolute value of the Seebeck coefficient increased with increasing sintering time, which might be due to a decrease in the stacking fault density accompanied by grain or crystallite growth. On the other hand, the power factor, which reflects the thermoelectric conversion efficiency of the present work, was slightly lower than that of the porous SiC semiconductors fabricated by conventional high-purity -SiC powder, it can be stated that the thermoelectric properties could be improved further by precise control of an acid-treatment process.

• Journal of Life Science
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• v.18 no.12
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• pp.1679-1685
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• 2008

Conjugated linoleic acid (CLA) is a naturally occurring compound found in dairy and beef products. It has been shown to suppress cancer cells and to induce apoptosis. Practically, there is emerging evidence that CLA can inhibit chemically induced carcinogenesis in various tissues. However, the molecular mechanisms of CLA on human MCF-7 breast cancer cells have not been clearly explained yet. In this report, we investigated the anti-cancer activity of CLA in MCF-7 cells. It was found that CLA could inhibit the growth of the MCF-7 cells and induce apoptosis, through modulating AMP-activated protein kinase (AMPK) and cyclooxygenase-2 (COX-2). AMPK acts as a cellular fuel gauge and responds to decreased cellular energy status by inhibiting ATP-consuming pathways and increasing ATP-synthesis. CLA treatment with variable concentrations and different time of same-dose CLA on MCF-7 cells resulted in a strong activation of AMPK and an inhibition of COX-2 expression. It supports that CLA induces apoptosis in CLA-treated MCF 7 cells. Therefore, the effects of CLA induced COX-2 expression via activating AMPK can provide new possibility into the understanding the molecular mechanisms of anti-cancer component.