• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.416-423
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• 1973

Formation of the complexes of alkaline earth metal ions with malonate and o-phthalate ions in aqueous, ethanol-water and acetone-water solutions (20% by volume) was studied at room temperature by the equilibrium ion exchange technique. This technique involved the measurements of distribution of radioactivity between cation exchange resin(Ion Exchange Resin CGC 241) and solution phases after the radioactive metal ions were equilibriated with the cation exchange resin in the presence of malonate or o-phthalate ions of varying concentrations. The pH of the solutions was controlled to 7.2~7.5, and the ionic strength of the solutions was kept at 0.10~0.11. The results of the present study indicated that the alkaline earth metal ions formed one-to-one complexes with the dibasic organic acids in all solvent systems examined. The present study showed that the relative stabilities of the complexes increased in the order: $Ba^{++}\;<\;Sr^{++}\;<\;Ca^{++}$ complexes. It was also observed that the relative tendency of the o-phthalate ion for the complex formation was somewhat greater than that of malonate ion in each solvent system. Furthermore, it was noted that the complexes were formed more readily in the mixed solvent than in the aqueous solution.

• Korean Journal of Agricultural Science
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• v.26 no.2
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• pp.39-48
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• 1999

This study was carried out to investigate the difference and genetic similarity at the level of molecular genetics. Genomic DNA was extracted from blood of Holstein, Korean cattle, Charolais, and hybrid between Korean cattle and charolais and RAPD(random amplified polymorphic DNAs) was analyzed by PCR(polymerase chain reaction). After genetic similarity value from different breeds are analyzed, genetic similarity was estimated by UPGMA(unweighted pair-group method using average). The results obtained from this study can be summarized as follows: 1. When genomic DNA which was extracted from different breeds was subjected to electrophoresis on 1.5% agarose gel, bigger than 12.2kb was appeared. Ratio by absorbance of $A_{260}/A_{280}$ was 1.75~2.10, indicating that genomic DNA was quite pure for RAPD analysis. 2. Different band patterns by RAPD were appeared according to the breeds in cattle. The best primer used to distinguish Holstein from other breeds was 5'-GAC CGC TTG T-3'. 3. A 340bp fragment was amplified in $33.0^{\circ}C$ of annealing temperature for the Holstein and Charolais breeds, but any amplification was not occurred in this annealing temperature for Korean cattle and hybrid. In addition, a 340bp fragment was amplified in $37.5^{\circ}C$ of annealing temperature for the Holstein and Korean cattle, but any amplification was not occurred in this annealing temperature for Charolais and hybrid. For the reaction of PCR. $37.5^{\circ}C$ and $33.0^{\circ}C$ of annealing temperature was shown to be best for genetic marker identification from Holstein, Charolais, and hybrid between Korean cattle and Charolais. 4. When genetic similarity from different breeds are analyzed at the both temperature of $33.0^{\circ}C$ and $37.5^{\circ}C$, the genetic similarity value of Holstein and Korean cattle, Holstein and Charolais, Korean cattle and Charolais, and Korean cattle and hybrid were 0.666~0.777, 0.615~0.666, 0.400~0.461 and 0.857~0.888, respectively. 5. It could be concluded that different breeds are capable of distinguishing by RAPD used random primer 5'-GAC CGC TTG T-3', genetic similarity from different breeds was appeared the higher genetic similarity value of Korean cattle and Charolais than that of Holstein between Korean cattle and Charolais by UPGMA.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.224-225
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• 2006

The Ethylene polymerization behavior of a series of polymethylene bridged dinuclear CGC $[Zr({\eta}^{5}:{\eta}^{1}-C_{9}H_{5}SiMe_{2}NCMe_{3})Me_{2}]_{2}[(CH_{2})_{n}]\;[_{n}=6(1),\;9(2),\;12(3)]$ in the cocatalytic activation with $Ph_{3}C^{+}B^{-}(C_{6}F_{5})_{4}\;(B_{1})\;or\;Ph_{3}C^{+}(C_{6}F_{5})_{3}B^{-}C_{6}F_{4}B^{-}(C_{6}F_{5})_{3}Ph_{3}C^{+}\;(B_{2})\;or\;B(C_{6}F_{5})_{3}\;(B_{3})$ were investigated to study the nuclearity effects as well as the counteranion effects. The ethylene polymerization and ethylene/1-hexene copolymerization were conducted at $30^{\circ}C$ It was found that both in ethylene polymerization and ethylene/1-hexene copolymerization, activities increased in the order of 1 < 2 < 3, which indicates the presence of longer bridge between two active sites contributes more efficiently to facilitate the polymerization activity.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.222-222
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• 2006

New types of constrained geometry complexes comprising rigid silacycloalkyl group incorporated into the bridging position between cyclopentadienyl and amido functionalities were prepared. The catalytic activities of olefin polymerization were influenced by the change of exo-cyclic ring size on bridge-head silacycloalkyl unit. It has been noted that the activities of this unique series increase with increasing size of the silacycloalkyl bridge and reach the maximum in six-membered silacyclohexyl-bridged CGC complex. It is noteworthy that conformation of silacycloalkanes gives rise to enhanced catalytic activity of the titanium center although the cyclic ring and titanium center are far remoted from each other.

• Polymer(Korea)
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• v.24 no.4
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• pp.445-452
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• 2000

The copolymerization of ethylene (E) and norbornene (N) was examined by using various metallocene catalysts and modified-MAO(MMAO) cocatalyst. For $C_2$-symmetry catalysts such as rac-Et(Ind)$_2$ZrC $l_2$, M $e_2$Si(Ind)$_2$ZrC $l_2$, M $e_2$Si(Cp)$_2$ZrC $l_2$ and Cs-symmetrical iPr(FluCp)ZrC $l_2$ as well as CGC and di-bridged zirconocene, the effects of catalyst structure and [N]/[E] feed ratio on catalyst activity, thermal property and [N] content of copolymer (COC) was investigated. For rac-Et(Ind)$_2$ZrC $l_2$ catalyst of a constant [N]/[E] feed ratio, the appropriate conditions of [Al]/[Zr] mole ratio, polymerization temperature and cocatalyst structure were found to be 3000, 4$0^{\circ}C$, MMAO cocatalyst, respectively. As [N]/[E] feed ratio increased, the incorporation of norbornene to copolymer increased while, the activity of catalyst decreased except for iPr(FluCp)ZrC $l_2$ With consideration of catalyst activity as well as N content, it was found that rac-Et(Ind)$_2$ZrC $l_2$/MMAO system exhibited relatively high activity and controllable $T_{g}$. Monomer reactivity ratio was determined by Kelen-Tudos method..

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.94-103
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• 2017

As automatic hacking tools and techniques have been improved, the number of new vulnerabilities has increased. The CVE registered from 2010 to 2015 numbered about 80,000, and it is expected that more vulnerabilities will be reported. In most cases, patching a vulnerability depends on the developers' capability, and most patching techniques are based on manual analysis, which requires nine months, on average. The techniques are composed of finding the vulnerability, conducting the analysis based on the source code, and writing new code for the patch. Zero-day is critical because the time gap between the first discovery and taking action is too long, as mentioned. To solve the problem, techniques for automatically detecting and analyzing software (SW) vulnerabilities have been proposed recently. Cyber Grand Challenge (CGC) held in 2016 was the first competition to create automatic defensive systems capable of reasoning over flaws in binary and formulating patches without experts' direct analysis. Darktrace and Cylance are similar projects for managing SW automatically with artificial intelligence and machine learning. Though many foreign commercial institutions and academies run their projects for automatic binary analysis, the domestic level of technology is much lower. This paper is to study developing automatic detection of SW vulnerabilities and defenses against them. We analyzed and compared relative works and tools as additional elements, and optimal techniques for automatic analysis are suggested.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.261-266
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• 2016

Background: Breast cancer is the leading cause of cancer death among women and the second in humans worldwide. Many published studies have suggested an association between MDR1 polymorphisms and breast cancer risk. Our aim was to study the association between genetic polymorphism of MDR1 at three sites (C3435T, G2677A/T, and C1236T) and their haplotype and the risk of breast cancer in Jordanian females. Materials and Methods: A case-control study involving 150 breast cancer cases and 150 controls was conducted. Controls were age-matched to cases. The polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP) technique and sequencing were performed to analyse genotypes. Results: The distribution of MDR1 C3435T genotypes differed between cases and controls [cases, CC 45.3%, CT 41.3%, and TT 13.3%; controls, CC 13.4%, CT 43.3%, and TT 30.2%, p < 0.001]. Similarly, the distribution of G2677A/T significantly differed [cases, GG 43.1 %, GT+GA 50.9% and AA+TT 6%; controls, GG 29.6 %, GT+GA 50.9%, and AA+TT 19.4%, p = 0.004]. On the other hand, genotype and allelotype distribution of C1236T was not statistically different between cases and controls (p=0.56 and 0.26, respectively). The CGC haplotype increased the risk to breast cancer by 2.5-fold compared to others, while TGC and TTC haplotypes carried 2.5- and 5-fold lower risk of breast cancer, respectively. Conclusions: Genetic polymorphisms of MDR1 C3435T and G2677A/T, but not C1236T, are associated with increased risk of breast cancer. In addition, CGC, TGC and TTC haplotypes have different impacts on the risk of breast cancer. Future, larger studies are needed to validate these findings.

• Childhood Kidney Diseases
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• v.8 no.1
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• pp.68-73
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• 2004

Both Gitelman syndrome and Bartter syndrome are autosomal recessively inherited renal tubular disorders characterized by hypokalemic metabolic alkalosis, salt wasting and normal to low blood pressure. Gitelman syndrome is caused by mutations in the thiazide-sensitive Na-Cl cotransporter (NCCT) and distinguished from Bartter syndrome, which is associated with mutations of several genes, by the presence of hypomagnesemia and hypocalciuria. In most of the patients with Gitelman syndrome, the disease manifests with transient episodes of muscular weakness and tetany in the adult period, but, often, is asymptomatic. We report here an 11 years-old female with Gitelman syndrome who presented with aggravation of epileptic seizure. The diagnostic work-up showed typical clinical features of metabolic alkalosis, hypokalemia, hypomagnesemia and hypocalciuria. We also identified a heterozygote mutation($^{642}$CGC(Arg)>TGC(Cys)) and an abnormal splicing in the SLC12A3 gene encoding NCCT.

• Journal of Satellite, Information and Communications
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• v.6 no.2
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• pp.66-71
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• 2011

This paper evaluates the performance and effectiveness of a layered coding scheme for an integrated mobile satellite systems, where the main target services are multimedia broadcasting and multicasting services (MBMS). In this integrated system, the satellite and complementary ground components (CGC) cooperate to provide high quality services. A layered coding scheme is a receiver driven adaptive schemes which adapts to the channel condition at the receiver. In this paper, we introduce a layered turbo coding scheme, and evaluates the performance in various scenarios, and discuss its effectiveness. The demonstrated results in the paper can be utilized in order to design an efficient integrated mobile satellite system, in the future.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.202-208
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• 1995

This study describes the effects of several components on PCR amplification used for RAPD. We used different concentrations of reaction components to obtaine discrete and reproducible PCR products from Pleurotus cornucopiae. The optimum concentrations of reaction components were found to be 80 ng of template DNA, 30 pmole of 10-mer primer, $200\;{\mu}M$ dNTP, 2mM $MgCl_2$, 50 mM KCl, 10 mM Tris-HCl(pH 9.0), 0.1% Triton X-100, 1.5 unit of Taq DNA polymerase (promega) in $50\;{\mu}l$ reaction volume. The optimum annealing temperature was $35^{\circ}C$. These results proved to be valuable for characterization of Pleurotus spp.