• ETRI Journal
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• 제40권3호
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• pp.396-409
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• 2018

Elliptic curve cryptography (ECC) can achieve relatively good security with a smaller key length, making it suitable for Internet of Things (IoT) devices. DNA-based encryption has also been proven to have good security. To develop a more secure and stable cryptography technique, we propose a new hybrid DNA-encoded ECC scheme that provides multilevel security. The DNA sequence is selected, and using a sorting algorithm, a unique set of nucleotide groups is assigned. These are directly converted to binary sequence and then encrypted using the ECC; thus giving double-fold security. Using several examples, this paper shows how this complete method can be realized on IoT devices. To verify the performance, we implement the complete system on the embedded platform of a Raspberry Pi 3 board, and utilize an active sensor data input to calculate the time and energy required for different data vector sizes. Connectivity and resilience analysis prove that DNA-mapped ECC can provide better security compared to ECC alone. The proposed method shows good potential for upcoming IoT technologies that require a smaller but effective security system.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.1973-1977
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• 2009

In the present study, at first, 2,4-Dihydroxy Salophen (2,4-DHS), has been synthesized by combination of 1, 2-diaminobenzene and 2,4-dihydroxybenzaldehyde in a solvent system. This ligand containing meta-quinone functional groups were characterized using UV-Vis and IR spectroscopies. Subsequently, the interaction between native calf thymus deoxyribonucleic acid (ct-DNA) and 2,4-DHS, was investigated in 10 mM Tris/HCl buffer solution, pH 7.2, using UV-visible absorption and fluorescence spectroscopies, thermal denaturation technique and viscosity measurements. From spectrophotometric titration experiments, the binding constant of 2,4-DHS with ct-DNA was found to be (1.1 ${\pm}\;0.2)\;{\times}\;10^4\;M^{-1}.$ The fluorescence study represents the quenching effect of 2,4-DHS on bound ethidium bromide to DNA. The quenching process obeys linear Stern-Volmer equation in extended range of 2,4-DHS concentration. Thermal denaturation experiments represent the increasing of melting temperature of DNA (about 3.5 ${^{\circ}C}$) due to binding of 2,4-DHS. These results are consistent with a binding mode dominated by interactions with the groove of ct-DNA.

• 한국미생물·생명공학회지
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• 제48권3호
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• pp.389-398
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• 2020

The prevalence of carbapenem-resistant Enterobacteriaceae (CRE) is increasing globally, resulting in high mortality rates. Although CRE is a relatively recent problem in Korea (the first case was not diagnosed until 2010), it is responsible for serious morbidities at an alarming rate. In this study, we carried out a molecular genetic analysis to determine the incidence of CRE and carbapenemase-producing Enterobacteriaceae (CPE) at a general hospital in Korea between August 2017 and August 2019. Forty strains of CPE were isolated from various clinical specimens and analyzed via antimicrobial susceptibility testing, polymerase chain reaction to detect β-lactamase genes, deoxyribonucleic acid sequencing, multilocus sequence typing, curing testing, and conjugal transfer of plasmids. The results demonstrated that all 40 isolates were multidrug-resistant. The fluoroquinolone susceptibility test showed that 75% of the Enterobacteriaceae isolates were resistant to ciprofloxacin, whereas 72.5% were resistant to trimethoprim-sulfamethoxazole. Further, conjugation accounted for 57.5% of all resistant plasmid transfer events, which is 4.3-fold higher than that observed in 2010 by Frost et al. Finally, the high detection rate of transposon Tn4401 was associated with the rapid diffusion and evolution of CPE. Our results highlight the rapid emergence of extensively drugresistant strains in Korea and emphasize the need for employing urgent control measures and protocols at the national level.

• Journal of Oral Medicine and Pain
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• 제20권2호
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• pp.497-513
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• 1995

Human genomic Deoxyribonucleic acid(DNA) was extracted from teeth by boiling, salting-out, phenol, boiling-phenol methods. The author compared DNA concentration and its purity, the accuracy of sex determination and the results of the D1S80 locus detection among above 4 methods. The following results were obtained : 1. DNA concentration was the highest in pulp with salting-out method and DNA purity was higher in pulp with salting-out and phenol methods than other 2 methods. 2. Sex determination was possible using of the pulp and the dentin of the teeth with four methods but, it was impossible in the enamel and some pulp with boiling method. 3. Amplification of D1S80 locus occurred from pulp and dentin with salting-out, phenol, and boiling-phenol methods. 4. There are no differences among the amplification of X-Y homologus amelogenin gene by application of 4 methods and salting-out, phenol methods efficiently makes available to amplification of D1S80 locus. From the investigation DNA extraction, sex determination, amplification of D1S80 locus was successfully accomplished with salting-out, phenol, boiling-phenol methods Therefore above 3 methods are available and applicable as forensic odontology for individual identification.

• Journal of Oral Medicine and Pain
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• 제21권2호
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• pp.317-329
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• 1996

Allelic frequency and genotype distribution of short tandem repeat(STR) F13A01 locus was analysed by polymerase chain reaction, polyacrylamide gel electrophoresis and silver staining from human genomic deoxyribonucleic acid(DNA) was extracted from 205 unrelated Korean to be applied to forensic identification and parentage testing as a database. The results were as follows : 1. 5 alleles and 11 genotypes of F13A01 locus were detected and heterozygosity value was 62.0% and the observed each alleles and allelic frequency was 3.2(0.363), 4(0.105), 5(0.063), 6(0.466), 16(0.002). 2. The allelic diversity value was 0.639 and the power of discrimination was 0.804.3. Compared with observed number of alleles and allele frequency in ethnic difference, result was appeared to be similar to that of Japanese and Asians, while was appeared to be much different to that of Blacks and Caucasians in the observed number of alleles and frequency of allele 3.2, 5, 7. From the above result of this investigation, the allelic frequency of STR F13A01 locus in the Korean was considerd to be useful for individual identification and parentage testing as a database.

• Plant Biotechnology Reports
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• 제2권4호
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• pp.233-238
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• 2008

Kadainou R-1, an interspecific hybrid grape derived from red (Vitis ficifolia var. ganebu) and white (V. vinifera cv. Muscat of Alexandria) grapes, accumulates high concentrations of anthocyanin in the berry skin. Hence, the expression of uridine 50 -diphosphate (UDP)-glucose:flavonoid 3-O-glucosyltransferase (UFGT), the key enzyme of the anthocyanin pathway, was examined in the berry skin of Kadainou R-1. As information on gene sequences of V. ficifolia var. ganebu and other wild grape species was unavailable, we performed GeneChip hybridization using biotin-labeled genomic deoxyribonucleic acid (DNA) to investigate how the genomic sequences of V. vinifera varieties and that of V. ficifolia var. ganebu differ. The study showed a lower correlation coefficient between V. vinifera cultivars and V. ficifolia var. ganebu than that among V. vinifera cultivars. The sequences of the UFGT gene derived from both parents of the red and white cultivars were sequenced in Kadainou R1 and revealed that both were expressed irrespective of the fact that it was not expressed in the white grape (male parent).

• 한국미생물·생명공학회지
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• 제20권3호
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• pp.243-248
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• 1992

동결건조법이 Nocardia mediterranei의 세포막 손상에 미치는 영향을 3H-thymidine 표지에 의한 DNA 유출 방법과 전자현미경으로 조사하였으며, 재수화 과정이 생존도에 미치는 영향을 연구하였다. 그 결과 N.mediterranei의 동결건조시 세포벽과 세포막의 손상이 세포 사멸의 원인으로 판명되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.143-143
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• 2008

Nanowires are promising options for building nanoscale electronic structures coming from high conductivity of nanowires. In particular, Deoxyribonucleic acid (DNA), which is structurally nanowire, can obtain highly ordered electronic components for nanocircuitry and/or nanodevices because of its very flexible length controllability, nanometer-size diameter, about 2 nm, and self-assembling properties. In this work, we used the method to form DNA-Nanowires (NWs) by using chemical treatment on Silicon (Si) surface, and Aminopropyl-triethoxysilane (APTES) was used as inducer of DNA sequence to modify the characteristics of Si surface. Moreover, we performed tilting technique to align DNA by the direction of flow of DNA solution. We investigated the assembly process between DNA molecules and APTES - coated Si surface according to the APTES concentration, from $1.2{\mu}\ell$ to $120{\mu}\ell$. Atomic Force Microscopy (AFM) images showed the combination rate of DNA molecules by the change of APTES concentration. As APTES concentration becomes thicker, aggregation of DNA molecules occurs, and this makes a kind of DNA networks. In this respect, we confirmed that there's a positive relationship between the concentration of APTES and the formation rate of DNA nanowires. Since there have been lots of research preceded to utilize DNA nanowires as template, so by using this positive relationship with proper alignment technique, realization of nano electronic devices with DNA nanowires might be feasible.

• 센서학회지
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• 제14권5호
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• pp.337-342
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• 2005

A silicon-based micro-reactor to amplify small amount of deoxyribonucleic acid (DNA) has been fabricated using micro-electro-mechanical systems (MEMS) technology. Polymerase chain reaction (PCR) of DNA requires a precise and rapid temperature control. A Pt sensor is integrated directly in the chamber for real-time temperature measurement and an infrared lamp is used as external heating source for non-contact and rapid heating. In addition to the real-time temperature sensing, PCR needs a rapid thermocycling for effective PCR. For a fast thermal response, the thermal mass of the reactor chamber is minimized by removal of bulk silicon volume around the reactor using double-side KOH etching. The transparent optical property of silicon in the infrared wavelength range provides an efficient absorption of thermal energy into the reacting sample without being absorbed by silicon reactor chamber. It is confirmed that the fabricated micro-reactor could be heated up in less than 30 sec to the denaturation temperature by the external infrared lamp and cooled down in 30 sec to the annealing temperature by passive cooling.

• 한국미생물·생명공학회지
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• 제13권4호
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• pp.417-422
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• 1985

Streptococcus faecalis var. liquefaciens에서 plasmid DNA를 분석한 결과, 4개의 plasmid를 가지고 있었으며, 각각의 대략적인 분자량은 6.8M-dal, 5.2Mdal, 2.6Mdal, 2.1Mdal로 측정되었다. 이 균주를 novobiocin으로 처리하여, 각각 다른 2개의 plasmid가 소실된 2개의 변이주를 얻었다. 이들 균주는 당발효성, 온도감수성, gelatin 용해성, 단백질응고성은 wild type과 동일하였으나 이중 한 균주가 lincomycin과 erythromycin에 대한 감수성을 나타내었다. 따라서 본 실험에서 검출한 4개의 plasmid는 당발효성 등의 특성과는 관련이 없는 것으로 추정할 수 있으며, pSK₂와 pSK₄의 두 plasmid 중 하나는 항생물질 저항성에 관련된 것으로 보인다.