• Korean Journal of Materials Research
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• v.2 no.6
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• pp.452-460
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• 1992

Effects of the microalloyed elements, temperatures and cooling rates on the strength and toughness of the medium carbon microalloyed hot forging steels obtained by air cooling(A.C.) method and the low carbon microalloyed forging steels by direct quenching(D.Q.) method were investigated. Combined additions of V+Nb produced the optimum combination of strength and toughness with ferrite-pearlite structure of the medium carbon steel by the A.C. method. 831MPa in UTS and 52.1J in toughness were obtained for 0.40c+0.12V+0.07Nb. It was martensite structure for the low carbon steel by the D.Q. method. The highest UTS and toughness obtained by Mo additions were 855MPa and 108j by 0.12C+0.10V+0.03Nb+1.13Mo respectively. Especially, the toughness of the low carbon steel was twice better than that of the medium carbon steel. 110$0^{\circ}C$was more appropriate than 120$0^{\circ}C$ for the reheating and forging temperature and 1.$2^{\circ}C$ /s was the best cooling rate from the viewpoint of the strength and toughness. Multiple regression analysis was used to quantify the influence of the microalloyed elements, temperatures and cooling rates on the strength, toughness, austenite grain size, and the pearlite interlamellar spacing.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.3
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• pp.9-15
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• 2021

Miniaturization of semiconductor devices has recently faced a physical limitation. To overcome this, 3D packaging in which semiconductor devices are vertically stacked has been actively developed. 3D packaging requires three unit processes of TSV, wafer grinding, and bonding, and among these, copper bonding is becoming very important for high performance and fine-pitch in 3D packaging. In this study, the effects of Ti nanolayer on the antioxidation of copper surface and low-temperature Cu bonding was investigated. The diffusion rate of Ti into Cu is faster than Cu into Ti in the temperature ranging from room temperature to 200℃, which shows that the titanium nanolayer can be effective for low-temperature copper bonding. The 12nm-thick titanium layer was uniformly deposited on the copper surface, and the surface roughness (R_q) was lowered from 4.1 nm to 3.2 nm. Cu bonding using Ti nanolayer was carried out at 200℃ for 1 hour, and then annealing at the same temperature and time. The average shear strength measured after bonding was 13.2 MPa.

• Journal of Chest Surgery
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• v.15 no.1
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• pp.90-97
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• 1982

Two hundred one patients of ventricular septal defect, which were operated at Seoul National University Hospital, were analysed on clinical background during the period from January, 1975 to December, 1980. The results were as follows: 1. Of the 201 patients, 118 patients were male [58.7%] and 83 patients were female [41.3%]. Their age ranged from 15 months to 40 years, and the mean age was 8.7 years. 40% of the patients were between 4 and 8 years. 2. The most common symptoms showed frequent U RI and exertional dyspnea. 3. On Kirklin`s anatomical classification, type I constituted 26.9%, type II 58.2%, type III 12.4%, and type IV 1.0%. We showed marked increased incidence of type I VSD as compared to Caucasians* 4. 46 cases were associated with other congenital cardiac diseases. They were PDA [13 cases], AI[11 ], ASD[6], PS[10], MI[4], and Double aortic arch [1]. 5. In 128 patients, who had complete hemodynamic data and were not associated with other congenital cardiac diseases, an attempt was made to correlate the EKG findings with the hemodynamic data, and defect size with the hemodynamic data. The children had variable distribution of PA syst. pr. and Rp/Rs. But most of adults had $R_P$/$R_S$of 0.15 or less. As $P_P$/$P_S$increased, the rate of operative complication increased also. 6. When a normal EKG pattern was present, $Q_P$/$Q_S$and $R_P$/$R_S$and $P_P$/$P_S$were relatively low. When EKG findings were LVH pattern, there was diastolic volume overload to left ventricle. As RVH, there was systolic pressure overload to right ventricle. And as BVH, there was mixed pattern of diastolic volume overload to left ventricle and systolic pressure overload to right ventricle. 7. Among patients in defect was less than 1 $cm^2$ per $M^2$ of BSA, $Q_P$/$Q_S$was less than 2:1, and $R_P$/$R_S$less than 0.25, and PAsyst. pr. less than 50 mmHg, and $P_P$/$P_S$was less than 0.5. But patients with the defect greater than 1 $cm^2$ per $M^2$ of BSA had no correlationship between $Q_P$/$Q_S$, $R_P$/$R_S$, PAsyst. pr. and defect size in each other. Most of patients with the defect greater than 2 $cm^2$/$M^2$ BSA, $R_P$/$R_S$was greater than 0.5. 8. Operative mortality rate was 9.5% [19 cases] among 201 patients. And complication rate including mortality rate was 22.9% [46 cases].

• The Korean Journal of Nuclear Medicine
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• v.13 no.1_2
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• pp.7-14
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• 1979

Radionuclide cardiac angiography has distinct advantages in safety, patient comfort, cost and ease of performance. This method offers diagnostic accuracy equivalent to that of cardiac catheterization. By this method the qualitative and quantitative diagnosis of the cardiac shunts are available. Also for it is repeatable with ease and more physiologic, it has application in following pre- and post-operative shunt patients. We performed the radionuclide cardiac angiographies in 147 cases of heart diseases and 26 cases of normal group. 1. The detection of left-to-right shunt was possible in 22 of 24 patients, and 2 patients were not diagnosed due to small shunt amount. (Qp/Qs<1.3) In 21 patients of right-to-left shunt, all were diagnosed by radionuclide cardiac angiography. 2. With the pulmonary time-activity curve, $C_2/C_1$ ratio was calculated. In normal control group, a range of $C_2/C_1$ ratios of $21{\sim}38%$ was established with a mean value of $28.6{\pm}4.6%$. In patients with left-to-right shunts determined by catheterization data, the range of $C_2/C_1$ ratio was $33{\sim}90%$, with a mean value of $67.8{\pm}12.2%$. 3. In 8 cases of left-to-right shunt, $Q_p/Q_s$ ratios determined by radionuclide cardiac angiography were compaired with those of cardiac catheterization. The correlation coefficient was 0.907. (P<0.001) 4. Postoperative radionuclide cardiac angiographies were done in 21 cases. 3 of 13 patients with left-to-right shunts were found to have residual shunts. 8 patients with right-to-left shunts were confirmed to have no residual shunt.

• Korean Journal of Pharmacognosy
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• v.44 no.1
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• pp.60-69
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• 2013

The worldwide prevalence and severity of allergic diseases including atopic and contact dermatitis has increased dramatically over the past decade, especially in developed countries. Mast cells are important effector cells in allergic reactions. The purpose of this study was undertaken to investigate the anti-allergic and anti-pruritic effects of Diospyros lotus leaf extract (DLE). DLE was prepared by extracting with distilled water. In the present study, we investigated the effect of DLE on the production of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\alpha}$) and histamine in rat peritoneal mast cells (RPMCs), and on the skin lesion, leukocyte infiltration and scratching behavior in mice. Phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 significantly increased TNF-${\alpha}$ and IL-$1{\beta}$ production compared with media control. However, TNF-${\alpha}$ and IL-6 production increased by PMA plus A23187 treatment were significantly inhibited by DLE in a dose-dependent manner. DLE also inhibited the histamine release from RPMCs stimulated by compound 48/80, which promotes histamine release. Moreover, DLE administration had an inhibitory effects on the scratching behavior induced by pruritogen (compound 48/80, histamine) in ICR mice. Furthermore, DLE inhibited the skin lesions, inflammatory and mast cells in hairless mice sensitized by 2,4-dinitrofluorobenzene (DNFB). DLE administration reduced the IL-4 and IgE production induced by DNFB sensitization in hairless mice. These results suggest that DLE has a potential use as a herb medicine for treatment against allergy and pruritus-related disease.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.139-142
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• 2003

Microwave dielectric properties of $Ca(Li_{1/4}Nb_{3/4})O_3-CaTiO_3$ ceramic systems were investigated with calcination temperatures and amounts of $CaTiO_3$ in the range of 0.2 to 0.4mol. $Ca(Li_{1/4}Nb_{3/4})O_3$ ceramics having orthorhombic crystal structure could be synthesized at $750^{\circ}C$ and sintered well at $1250^{\circ}C$. They showed the dielectric constant of 26, quality factor($Q{\times}f_o$) of 13,000 and temperature coefficient of resonant frequency(${\tau}_f$) of $-49{\pm}2ppm/^{\circ}C$ With adding the $CaTiO_3$ amount the dielectric constant and ${\tau}_f$ increased due to the solute of $CaTiO_3$ but the quality factor decreased. The 0.7$Ca(Li_{1/4}Nb_{3/4})O_3-0.3CaTiO_3$ ceramic showed the dielectric constant of 44, quality factor($Q{\times}f_o$) of 12,000 and ${\tau}_f$ of $-9{\pm}1ppm/^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.309-312
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• 2004

We performed exon trapping in order to locate functional genes on chicken chromosomes (GGA) and to identify functional gene sequences from chicken cosmids. Sequence analysis of 100 clones revealed 17 putative exons, five of which were identified with known sequences in a gene database search: thymopoietin beta (TMPO), U5 snRNP-specific 40 kDa protein (HPRP8BP), dihydropyridine receptor alpha 1 subunit (CACNL1A3), cystein string protein (CPS) and C15orf4. We attempted to map the genes to chicken chromosomes by using FISH and linkage analysis. The chromosomal localizations were GGA1 (TMPO), GGA10 (C15orf4), GGA23 (HPRP8BP) and GGA28 (CPS) by FISH and linkage analysis, while that of CACNL1A3 was predicted to be on a microchromosome by FISH but not by linkage analysis. Comparative mapping analyses between chickens and humans for the genes revealed both known and new synteny. The syntenic conservation between GGA1 and human chromosome (HSA) 12q23 (TMPO) and between GGA10 and HSA15q25 (C15orf4), were consistent with a recent publication, while two new syntenies were observed between GGA28 and HSA20q13.3 in CPS and between GGA23 and HSA1p34-35 in HPRP8BP. The information of presently mapped genes can contribute as anchor markers based on functional genes and the construction of a comparative map.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.205-214
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• 2020

Background: This article aims to compare and analyze the contents of ginsenosides in ginseng of different plant ages from different localities in China. Methods: In this study, 77 fresh ginseng samples aged 2-4 years were collected from 13 different cultivation regions in China. The content of eight ginsenosides (Rg₃, Rc, Rg₁, Rf, Rb₂, Rb₁, Re, and Rd) was determined using rapid resolution liquid chromatography coupled with quadrupole-time-of-flight tandem mass spectrometry (RRLC-Q-TOF MS/MS) to comparatively evaluate the influences of cultivation region and age. Results: Ginsenoside contents differed significantly depending on age and cultivation region. The contents of ginsenosides Re, Rc, Rg₁, Rg₃, and Rf increased with cultivation age, whereas that of ginsenoside Rb₁ peaked in the third year of cultivation. Moreover, the highest ginsenoside content was obtained from Changbai (19.36 mg/g) whereas the lowest content was obtained from Jidong (12.05 mg/g). Ginseng from Jilin Province contained greater total ginsenosides and was richer in ginsenoside Re than ginseng of the same age group in Heilongjiang and Liaoning provinces, where Rb₁ and Rg₁ contents were relatively high. Conclusion: In this study, RRLC-Q-TOF MS/MS was used to analyze ginsenoside contents in 77 ginseng samples aged 2-4 years from different cultivation regions. These patterns of variation in ginsenoside content, which depend on harvesting location and age, could be useful for interested parties to choose ginseng products according to their needs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.12
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• pp.1085-1089
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• 2002

The circular cavity resonator which can measure the dielectric properties of dielectrics in the Ka-band(26.5GHz∼400Hz) frequency range was designed and fabricated. A structure of the resonator is divided into two equal parts of the length and the dielectric plate sample is placed between two halves. Exciting and detecting of the resonator is Performed by WR28 rectangular waveguides using Bethe's small hole coupling. The GaAs plate sample, whose performance is known to be 13 in millimeter wave range, was used for the verification of the performance of the fabricated circular cavity resonator In the measurement of GaAs single crystal using that resonator, the resonant frequency of the dominant TE$\sub$011/ mode, the permittivity and Q${\times}$f$\sub$0/ were measured as 26.69GHz, 12.9 and 124,000GHz, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2231-2235
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• 2015

Genome-wide association studies (GWASs) of the entire genome provide a systematic approach for revealing novel genetic susceptibility loci for breast cancer. However, genetic association studies have hitherto been primarily conducted in women of European ancestry. Therefofre we here performed a pilot GWAS with a single nucleotide polymorphism (SNP) array 5.0 platform from $Affymetrix^{(R)}$ that contains 443,813 SNPs to search for new genetic risk factors in 89 breast cancer cases and 46 healthy women of Indonesian ancestry. The case-control association of the GWAS finding set was evaluated using PLINK. The strengths of allelic and genotypic associations were assessed using logistic regression analysis and reported as odds ratios (ORs) and P values; P values less than $1.00{\times}10^{-8}$ and $5.00{\times}10^{-5}$ were required for significant association and suggestive association, respectively. After analyzing 292,887 SNPs, we recognized 11 chromosome loci that possessed suggestive associations with breast cancer risk. Of these, however, there were only four chromosome loci with identified genes: chromosome 2p.12 with the CTNNA2 gene [Odds ratio (OR)=1.20, 95% confidence interval (CI)=1.13-1.33, $P=1.08{\times}10^{-7}$]; chromosome 18p11.2 with the SOGA2 gene (OR=1.32, 95%CI=1.17-1.44, $P=6.88{\times}10^{-6}$); chromosome 5q14.1 with the SSBP2 gene (OR=1.22, 95%CI=1.11-1.34, $P=4.00{\times}10^{-5}$); and chromosome 9q31.1 with the TEX10 gene (OR=1.24, 95%CI=1.12-1.35, $P=4.68{\times}10^{-5}$). This study identified 11 chromosome loci which exhibited suggestive associations with the risk of breast cancer among Indonesian women.