• Korean Journal of Materials Research
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• v.4 no.2
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• pp.194-205
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• 1994

In this research, we attempt to fabricate an excellent CFRC(Carbon Fiber Reinforced Carbon), which has good thermal and mechanical properties, with 8H/satin woven fabric prepreg, high modulus and high strength type continuous carbon fiber and raw coal tar pitch(RCTP) matrix or THF soluble fraction(THFSP) matrix which has good graphitizability. Green bodies were fabricated with hot press molding technique and CFRC samples were made after carbonization, impregnation, recarbonization and graphitization steps. For the purpose of characterization of the physical properties, SEM, polarized light microscope, TGA were observed, and tested flexural strength, modulus and ILSS. After heat treating the THFSP matrix up to $2300^{\circ}C$, the value of $C_0$/2 was 3.380$\AA$, which is analogous to the structure of natural graphite and the value of 2$\theta$ is $26.276^{\circ}$ approached to the Bragg's angle of natural graphite. As a result of TGA to test the high temperature air oxidation, the THFSP matrix, graphitized up to $2300^{\circ}C$, exhibited the best air oxidation resistance. And mechanical properties were increased up to 65~70% as fiber volume fraction increased. Because of the good orientation graphitizability, the fracture surface of THFSP matrix CFRC is very good.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.249-253
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• 2016

The inky cap, Coprinellus congregatus, produces several laccase isozymes during its life cycle: both hyphal tip laccase and sclerotial laccase are involved in the fungal development. When this fungus was transferred to an acid liquid medium (pH 4.0-4.5), a new laccase was synthesized and secreted into the culture supernatant. In order to examine its regulation by external pH, green fluorescent protein gene was ligated at the downstream of the promoters having different lengths. These expression vectors having different promoter lengths were inserted into the fungal transformation vector, pBARGEM7-1. These expression vectors were introduced to the mating type a1 and a2 monokaryons, and the transformants were selected by the phosphinothricin resistance. Transformant a1 (a1TF) and transformant a2 (a2TF) were mated with each other to generate homozygotic dikaryon transformants. All these transformants were grown in neutral liquid medium for 5 days, and then the whole cell homogenates were transferred to the acidic liquid medium (pH 4.1). After 36 h incubation at $25^{\circ}C$, cells were harvested for the analysis of GFP expression. GFP expression was detected in the transformant having full-length promoter (2.0 kb), but other transformants having shorter length promoter (shorter than 1.29 kb) failed to show the fluorescence. Therefore, the acid-responsive element in the laccase promoter should be localized between -2.0 kb ~ -1.29 kb region.

• The Journal of the Korean Society for Microbiology
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• v.21 no.4
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• pp.423-434
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• 1986

The role of macrophages in the resistance of ICR mice to Candida albicans and Salmonella typhimurium was assessed using silica, agent which selectively inactivates macrophages or poly-2-vinylpyridine-N-oxide(PVNO), a lysosomal stabilizing agent. In addition, effect of silica on humoral and cellular immune responses to sheep red blood cells(SRBC) or polyvinylpyroridone(PVP) was examind. Colonyforming units(CFU) of C. albicans or S. typhimurium in the spleen, livers and kidneys of silica-treated or diluent-treated mice were enumerated at various times after infection. Silica was given i. v. to mice at 4 days or 1 day before infection. Although there was no apparent differences in the number of CFU of C. albicans cultured from the spleens or livers of silica-treated and control mice at every assay period, significant differences in the number of CFU of C. albicans in the kidneys of silica-treated and control mice. Namely, silica given to mice 1 day before infection significantly increased the number of CFU of C. albicans in the kidneys at 2, 4 and 6 days after infection, but did not change the number of CFU at 8 days after infection. Silica given to mice at 4 days before infection significantly increased the number CFU in the kidneys at 2 and 4 days after infection, but rather decreased the number of CFU at 8 days after infection. The number of CFU of C. albians cultured from the kidneys of splenectomized which were experimentally infected mice was similar to the number recovered from sham-operated mice at 4 and 8 days postinfection irrespective of time of infection relative to operation. The pretreatment of mice with PVNO appeared to abrogate the silica-induced susceptibility of mice to C. albicans. PVNO alone showed somewhat protective effect against challenge with C. albicans. In contrast, silica treatment did not alter the number of CFU of S. typhimurium recovered from the spleens and kidneys of mice. The administration of silica to mice at 4 days or 1 day before SRBC immunization significantly suppressed delayed-type hypersensitivity(DTH) reactions to SRBC and antibody production to SRBC, a thymus-dependent antigen and PVP, a thymus-independent antigen. These results provide evidence that macrophages play an important role in susceptibility to Candida infection and strongly demonstrated that macrophages play an essential role in the induction of immune responses in mice.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.1
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• pp.15-18
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• 2020

'Luckyone 2ho' is a new orchardgrass (Dactylis glomerata L.) cultivar developed by the National Institue of Animal Science (NIAS) in 2017. To develope the new variety of orchardgrass, 5 superior clones were selected and polycrossed for seed production. The agronomic growth characteristics and forage productivity of 'Luckyone 2ho' were examined at Cheonan from 2012 to 2014, and regional trials were conducted in Cheonan, Pheonchang, Jinju and Jeju from 2015 to 2017, respectively. 'Luckyone 2ho' showed medium type growth habit in fall, and medium in length of flag leaf and very long upper internode. Plant height of 'Luckyone 2ho' was 3 cm less than that of standard cultivar, 'Potomac' and heading date was 1 days later than 5th May compared to standard cultivar, 'Potomac'. Characteristics such as waterlogging and disease resistance of 'Luckyone 2ho' were stronger or better than those of standard cultivar, 'Potomac', Especially, dry matter yield of 'Luckyone 2ho'(15,980 kg/ha) increased 9 % compared to that of standard cultivar, 'Potomac'(14,702 kg/ha). Nutritive values were appeared to be similar in both varieties except in Vitro dry matter digestibility(IVDMD) and crude protein and total digestible nutrients (TDN).

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.140-140
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• 2018

The 3D interconnect technologies have been appeared, as the density of Integrated Circuit (IC) devices increases. Through Silicon Via (TSV) process is an important technology in the 3D interconnect technologies. And the process is used to form a vertically electrical connection through silicon dies. This TSV process has some advantages that short length of interconnection, high interconnection density, low electrical resistance, and low power consumption. Because of these advantages, TSVs could improve the device performance higher. The fabrication process of TSV has several steps such as TSV etching, insulator deposition, seed layer deposition, metallization, planarization, and assembly. Among them, TSV metallization (i.e. TSV filling) was core process in the fabrication process of TSV because TSV metallization determines the performance and reliability of the TSV interconnect. TSVs were commonly filled with metals by using the simple electrochemical deposition method. However, since the aspect ratio of TSVs was become a higher, it was easy to occur voids and copper filling of TSVs became more difficult. Using some additives like an accelerator, suppressor and leveler for the void-free filling of TSVs, deposition rate of bottom could be fast whereas deposition of side walls could be inhibited. The suppressor was adsorbed surface of via easily because of its higher molecular weight than the accelerator. However, for high aspect ratio TSV fillers, the growth of the top of via can be accelerated because the suppressor is replaced by an accelerator. The substitution of the accelerator and the suppressor caused the side wall growth and defect generation. The suppressor was used as Single additive electrodeposition of TSV to overcome the constraints. At the electrochemical deposition of high aspect ratio of TSVs, the suppressor as single additive could effectively suppress the growth of the top surface and the void-free bottom-up filling became possible. Generally, copper was used to fill TSVs since its low resistivity could reduce the RC delay of the interconnection. However, because of the large Coefficients of Thermal Expansion (CTE) mismatch between silicon and copper, stress was induced to the silicon around the TSVs at the annealing process. The Keep Out Zone (KOZ), the stressed area in the silicon, could affect carrier mobility and could cause degradation of the device performance. Cobalt can be used as an alternative material because the CTE of cobalt was lower than that of copper. Therefore, using cobalt could reduce KOZ and improve device performance. In this study, high-aspect ratio TSVs were filled with cobalt using the electrochemical deposition. And the filling performance was enhanced by using the suppressor as single additive. Electrochemical analysis explains the effect of suppressor in the cobalt filling bath and the effect of filling behavior at condition such as current type was investigated.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.5
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• pp.55-63
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• 2018

Recently, the use of duplex stainless steel which with a two-phase microstructure (equal mixture of ferrite and austenite) has been increased in a variety of industrial fields due to higher strength leading to weight saving, greater corrosion resistance(particularly, stress corrosion cracking) and lower price. However, currently, stainless steels are not included in the structural materials of Korean Building Code and corresponding design standards are not specified. In this paper, experimental studies have been performed to investigate the structural behaviors of duplex stainless steel (STS329FLD) bolted connection with two bolts for providing the design data. Main variables are shear connection type (single shear and double shear) and end distance parallel to the direction of applied force. Fracture modes at the final step of test were classified into typical block shear fracture, tensile fracture and curling. Curling occurrence in single shear connection led to ultimate strength drop by up to 20%. Test strengths were compared with those by current design specifications such as AISC/AISI/KBC, EC3 and AIJ and proposed equations by existing studies. For specimens with no curling, Clement & Teh's equation considering the active shear plane provided a higher strength estimation accurancy and for specimens with curling, Kim & Lim's equation considering strength reduction by curling was also overly unconservative to predict the ultimate strength of curled connections.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.121-127
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• 1993

The barley plant for whole crop forage is advantageous to have traits with higher photosynthetic rate, biomass, lodging resistance, and awnless spikes. The objective of this study is to investigate performance of near-isogenic line pairs for the awned and awnless in the field, and to observe the variations in photosynthetic rate, yield and their related traits under removal of flag leaf and awns. Grain yield was 6% higher, but biomass and photosynthetic rate were 6～16% and 6% lower in the awned line than those in the awnless grown in the field ,respectively. Defoliation of flag leaf resulted in approximately 3～4%, and 5～6% decreases in 1,000 kernels and grain weights, respectively. Deawning at the heading stage of the long awned line decreased 1,000 kernels and grain weights by 7% and 15%, respectively, The removal of both assimilative tissues caused 14 and 21% decrements in 1,000 kernels and grain weights. Apparent photosynthetic rate of leaf blade in awnless line was 6.1 -9. 7 $CO_2$$_2$ ${\mu}$mole $m^{-2}$ $s{-1}$, much higher than that in awned line. The relative rates in the second and third leaves were about 93% and 55～63%, respectively as compared with that in the flag leaf. The results of the experiments suggest that the awnless line selected for whole crop forage is a potential plant type with higher photosynthetic rate, leaf area and greater biomass.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.261-264
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• 2004

New orchardgrass(Dactylis glomerata L.) variety named as 'Kordi' was developed by the National Livestock Research Institute(NLRI) in 2003. Five superior clones on selected to develope the new variety of orchardgrass, and polycrossed for synthetic seed production. Synthetic seeds were examined on the agronomic growth characteristics and forage production at Suwon from 1995 to 1998, and regional trials were conducted in Suwon, Pyungchang and Jeju from 2001 to 2003 and Icsan in 2003, respectively. 'Kordi' showed semi-erect growth habit in fall and spring, and long type in length of flag leaf and short in upper internode. Plant height of 'Kordi' was little short compared to that of standard variety, Ambassador, and heading date was delayed about 3 days as 14th May compared to Ambassador. Characters such as winter hardiness. lodging tolerance, regrowth, disease resistance of 'Kordi' were stronger or better than those of Ambassador. 'Kordi' showed $10\%$ higher dry matter yield as 15,174 kg/ha compared to Ambassador. Nutritive value was appeared to be similar in both varieties.

• Journal of Food Hygiene and Safety
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• v.33 no.3
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• pp.193-199
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• 2018

In this study, PAT protein of genetically modified maize was prepared from the recombinant E. coli strain BL21 (DE3), and mice were immunized with the recombinant PAT protein. After cell fusion and cloning, two hybridoma cells (PATmAb-7 and PATmAb-12) were chosen since the monoclonal antibodies (Mabs) produced by them were confirmed to be specific to PAT protein in the indirect enzyme-linked immunsorbent assay (ELISA) and western blot tests. There were no cross-reactions of either Mabs to other GM proteins or to the extracts of non-GM maize. The ELISA based on the PATmAb-7 can sensitively detect 0.3 ng/g PAT protein in corn. These results indicate that the developed Mabs can be used as bio-receptors in the development of immunosensors and biosensors for the rapid and simple detection of GM corn adulterated in foods.

• The Korean Journal of Food And Nutrition
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• v.31 no.3
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• pp.425-434
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• 2018

Metabolic syndrome is a risk factor for cardiovascular and type 2 diabetes. This study was conducted to examine the relevance between nutrition intake, meal quality, and high-sensitivity C-reactive protein in Koreans with metabolic syndrome. The 2,536 subjects, aged 19~64, who participated in 2015 National Nutrition Survey were included in this study. The 24-hour recall method was employed to analyze nutrition intake and dietary quality. Subjects were grouped into either the non-metabolic syndrome group (n=1,938) or the metabolic syndrome group (n=598). Total males and females were divided into 3 groups according to the high-sensitivity C-reactive protein (hs-CRP) level to study its relationship to metabolic syndrome and its components, including odds ratio (OR) and confidence interval (CI). Results showed the homeostasis model assessment of insulin resistance (HOMA-IR) value was higher in the metabolic syndrome group (3.37) than non-metabolic syndrome group (1.57) (p<0.001). In the Index of Nutrition Quality, males in the non-metabolic syndrome group showed higher niacin (p<0.05) than males in metabolic syndrome group. Females in the non-metabolic syndrome group had higher vitamin $B_1$ (p<0.01), vitamin $B_2$ (p<0.001), niacin (p<0.05), calcium (p<0.001), and phosphate (p<0.01). Female in the high hs-CRP group showed high OR in blood glucose component (OR 2.488, 95% CI: 1.269~4.879) and metabolic syndrome risk (OR 2.856, 95% CI: 1.292~6.314). Females in the middle hs-CRP group had high triglycerides component (OR 2.956, 95% CI: 1.920~4.551), compared to the low hs-CRP group. The study showed females with higher hs-CRP had a higher risk of metabolic syndrome.