• Journal of Microbiology and Biotechnology
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• 제26권8호
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• pp.1398-1403
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• 2016

The simultaneous detection and accurate identification of hepatitis A virus (HAV) is critical in food safety and epidemiological studies to prevent the spread of HAV outbreaks. Towards this goal, a one-step duplex reverse-transcription (RT)-PCR method was developed targeting the VP1/P2B and VP3/VP1 regions of the HAV genome for the qualitative detection of HAV. An HAV RT-qPCR standard curve was produced for the quantification of HAV RNA. The detection limit of the duplex RT-PCR method was 2.8 × 10¹ copies of HAV. The PCR products enabled HAV genotyping analysis through DNA sequencing, which can be applied for epidemiological investigations. The ability of this duplex RT-PCR method to detect HAV was evaluated with HAV-spiked samples of fresh lettuce, frozen strawberries, and oysters. The limit of detection of the one-step duplex RT-PCR for each food model was 9.4 × 10² copies/20 g fresh lettuce, 9.7 × 10³ copies/20 g frozen strawberries, and 4.1 × 10³ copies/1.5 g oysters. Use of a one-step duplex RT-PCR method has advantages such as shorter time, decreased cost, and decreased labor owing to the single amplification reaction instead of four amplifications necessary for nested RT-PCR.

• 한국발생생물학회지:발생과생식
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• 제23권4호
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• pp.367-375
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• 2019

Pufferfish (Takifugu spp.) are economically important edible marine fish. Mistakes in pufferfish classification can lead to poisoning; therefore, accurate species identification is critical. In this study, we used the mtDNA cytochrome c oxidase subunit I gene (COI) to design specific primers for six Takifugu species among the 21 domestic or imported pufferfish species legally sold for consumption in Korea. We rapidly and simultaneously identified these pufferfish species using a highly efficient, multiplex polymerase chain reaction (PCR) system with the six species-specific primers. The results showed that species-specific multiplex PCR (multiplex species-specific polymerase chain reaction; MSS-PCR) either specifically amplified PCR products of a unique size or failed. MSS-PCR yielded amplification fragment lengths of 897 bp for Takifugu pardalis, 822 bp for T. porphyreus, 667 bp for T. niphobles, 454 bp for T. poecilonotus, 366 bp for T. rubripes, and 230 bp for T. xanthpterus using the species-specific primers and a control primer (ca. 1,200 bp). We visualized the results using agarose gel electrophoresis to obtain accurate contrasts of the six Takifugu species. MSS-PCR analysis is easily performed and provides identification results within 6 h. This technique is a powerful tool for the discrimination of Takifugu species and will help prevent falsified labeling, protect consumer rights, and reduce the risk of pufferfish poisoning..

• Smart Structures and Systems
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• 제26권6호
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• pp.693-701
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• 2020

The conventional Kalman Filter (KF) provides a promising way for structural state estimation. However, the physical parameters of structural systems or models should be available for the estimation. Moreover, it is not applicable when the loadings applied to the structures are unknown. To circumvent the aforementioned limitations, a two-stage KF with unknown input approach is proposed for the simultaneous identification of structural parameters and unknown loadings. In stage 1, a modified observation equation is employed. The structural state vector is estimated by KF on the basis of structural parameters identified at the previous time-step. Then, the unknown input is identified by Least Squares Estimation (LSE). In stage 2, based on the concept of sensitivity matrix, the structural parameters are updated at the current time-step by using the estimated structural states obtained from stage 1. The effectiveness of the proposed approach is numerically validated via a five-story shearing model under random and earthquake excitations. Shaking table tests on a five-story structure are also employed to demonstrate the performance of the proposed approach. It is demonstrated from numerical and experimental results that the proposed approach can be used for the identification of parameters of structure and the external force applied to it with acceptable accuracy.

• 한국식품과학회지
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• 제24권2호
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• pp.171-176
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• 1992

더덕(Codonopsis lanceolata)의 휘발성 향기성분을 분석하기 위해 gas co-distillation(GCD), solvent extraction/fractionation(SLF), headspace sampling(HSS) 방법을 사용하여 향기성분을 분리농축하고 분석 비교한 결과 SEF와 HSS 방법으로 얻은 농축물들의 향이 원래의 더덕향과 가장 유사했으며 gas chromatogram들의 양상도 비슷했으나 peak들의 크기에 있어서 차이를 보였다. SEF 농축물에서는 달콤한 향을 기리고 HSS 농축물에서는 풋내를 비교적 강하게 느낄 수 있었으나 GCD 농축물의 경우 일정 증류시간이 지나면 한악취를 느낄 수 있었다. SEF와 HSS 방법은 GCD에 비해서 적은 조작 단계로 손쉽게 빠른 시간내에 분리 농축이 가능했다. 농축한 향기성분은 GC-MS와 극성이 다른 두 column을 사용한 GC-RI system을 이용하여 확인하였다. 특히 GC-RI는 isomer의 확인에 효과적이었으며 극성 FFAP column은 극성 화합물의 확인에 보다 적합했다. 35가지의 향기성분들을 동정하였는데 그중 24개의 성분들은 simultaneous distillation extraction 농축물에서는$^{(5)}$ 확인되지 않았던 향기성분들이다. 화인된 성분들중 trans-2-hexenal, cis-3-hexen-1-ol, trans-2-hexen-1-ol, hexanol은 더덕의 풋내를, 1-octen-3-ol은 신선한 풍미를 그리고 amyl propionate를 비롯한 다수의 에스터 화합물 등은 더덕 특유의 달콤한 향에 복합적으로 작용할 것으로 추정된다.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1902-1906
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• 2010

A microchip electrophoresis (ME) method was developed using a programmed field strength gradients (PFSG) for the single nucleotide polymorphism (SNP) based fast identification of cattle breeds. Four different Korean cattle (Hanwoo) and Holstein SNP markers amplified by allele-specific polymerase chain reaction were separated in a glass microchip filled with 0.5% poly(ethyleneoxide) ($M_r$ = 8 000 000) by PFSG as follows: 750 V/cm for 0 - 14 s, 166.7 V/cm for 14 - 31 s, 83.3 V/cm for 31 - 46 s, and 750 V/cm for 46 - 100 s. The cattle breeds were clearly distinguished within 45 s. The ME-PFSG method was 7 times and 5 times faster than the constant electric field ME method and the capillary electrophoresis- PFSG method, respectively, with a high resolving power ($R_s$ = 5.05 - 9.98). The proposed methodology could be a powerful tool for the fast and simultaneous determination of SNP markers for various cattle breeds with high accuracy.

• 한국약용작물학회지
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• 제12권2호
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• pp.102-107
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• 2004

This study was carried out to establish an optimum method for identifying the volatile components of Magnolia ovobata Thunb. using the dynamic headspace (Purge & Trap) and simultaneous distillation and extraction (SDE) method. Between the two different identification analysis, the volatile components were more easily detected in the SDE than the Purge & Trap method. Among the identified volatile components, the 12 compounds were detected to have similar retention times and match quality within the 45 minutes in both identification methods. The maximum values of the major volatile components were detected differently by SDE and (Purge & Trap) method such as ${\alpha}-pinene$ (3.4, 18.2%), ${\beta}-pinene$ (3.5, 10.3%), l-limonene (5.2, 15.4%). These results indicated that the Dynamic Headspace (Purge & Trap) was much more reliable method for identifying the volatile components of Magnolia ovobata Thunb. as compared to the SDE method.

• 응용통계연구
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• 제31권1호
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• pp.1-11
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• 2018

최근 다변량 공정관리는 다양한 응용 분야에서 중요해지고 있는 추세이다. 예를 들어, 제조 산업 분야에서는 다변량 품질특성치를 동시에 모니터링할 필요가 있다. 그러나, 다변량 관리도는 이상신호가 발생한 경우 그 원인이 되는 개별적인 변수를 식별하기가 어렵기 때문에, 실제로는 기대만큼 유용하게 쓰이고 있지 않은 형편이다. 이에 본 논문에서는 새로운 관측치에 대한 개별적인 신뢰구간을 사용하여 이상신호의 원인을 탐지하는 세 가지 방법을 소개하고, 시뮬레이션 연구를 통해 이상신호의 원인이 되는 개별적인 변수를 식별하고 해석하는 데 있어 주의할 점이 무엇인지 살펴보기로 한다.

• 한국축산식품학회지
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• 제35권3호
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• pp.382-388
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• 2015

A duplex real-time polymerase chain reaction (PCR) based assay for the detection of porcine and horse meat in sausages was designed by using EvaGreen fluorescent dye. Primers were selected from mitochondrial 12S rRNA and 16S rRNA genes which are powerful regions for identification of horse and porcine meat. DNA from reference samples and industrial products was successfully extracted using the GIDAGEN® Multi-Fast DNA Isolation Kit. Genomes were identified based on their specific melting peaks (Mp) which are 82.5℃ and 78℃ for horse and porcine, respectively. The assay used in this study allowed the detection of as little as 0.0001% level of horse meat and 0.001% level of porcine meat in the experimental admixtures. These findings indicate that EvaGreen based duplex realtime PCR is a potentially sensitive, reliable, rapid and accurate assay for the detection of meat species adulterated with porcine and horse meats.

• Smart Structures and Systems
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• 제14권1호
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• pp.55-70
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• 2014

The paper presents a multi-objective optimization strategy for a multi-type sensor placement for Structural Health Monitoring (SHM) of long span bridges. The problem is formulated for simultaneous placement of strain sensors and accelerometers (heterogeneous network) based on application demands for SHM system. Modal Identification (MI) and Accurate Mode Shape Expansion (AMSE) were chosen as the application demands for SHM. The optimization problem is solved through the use of integer Genetic Algorithm (GA) to maximize a common metric to ensure adequate MI and AMSE. The performance of the joint optimization problem solved by GA is compared with other established methods for homogenous sensor placement. The results indicate that the use of a multi-type sensor system can improve the quality of SHM. It has also been demonstrated that use of GA improves the overall quality of the sensor placement compared to other methods for optimization of sensor placement.

• Journal of Microbiology and Biotechnology
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• 제26권2호
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• pp.213-225
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• 2016

To reduce attrition in drug development, it is crucial to consider the development and implementation of translational phenotypic assays as well as decipher diverse molecular mechanisms of action for new molecular entities. High-throughput fluorescence and confocal microscopes with advanced analysis software have simplified the simultaneous identification and quantification of various cellular processes through what is now referred to as high-content screening (HCS). HCS permits automated identification of modifiers of accessible and biologically relevant targets and can thus be used to detect gene interactions or identify toxic pathways of drug candidates to improve drug discovery and development processes. In this review, we summarize several HCS-compatible, biochemical, and molecular biology-driven assays, including immunohistochemistry, RNAi, reporter gene assay, CRISPR-Cas9 system, and protein-protein interactions to assess a variety of cellular processes, including proliferation, morphological changes, protein expression, localization, post-translational modifications, and protein-protein interactions. These cell-based assay methods can be applied to not only 2D cell culture but also 3D cell culture systems in a high-throughput manner.