• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.146-154
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• 2020

With the advantages of biocatalytic method, enzymes have been excavated for the synthesis of chiral amino acids by the reductive amination of ketones, offering a promising way of producing pharmaceutical intermediates. In this work, a robust phenylalanine dehydrogenase (PheDH) with wide substrate spectrum and high catalytic efficiency was constructed through rational design and active-site-targeted, site-specific mutagenesis by using the parent enzyme from Bacillus halodurans. Active sites with bonding substrate and amino acid residues surrounding the substrate binding pocket, 49L-50G-51G, 74M,77K, 122G-123T-124D-125M, 275N, 305L and 308V of the PheDH, were identified. Noticeably, the new mutant PheDH (E113D-N276L) showed approximately 6.06-fold increment of k_cat/Km in the oxidative deamination and more than 1.58-fold in the reductive amination compared to that of the wide type. Meanwhile, the PheDHs exhibit high capacity of accepting benzylic and aliphatic ketone substrates. The broad specificity, high catalytic efficiency and selectivity, along with excellent thermal stability, render these broad-spectrum enzymes ideal targets for further development with potential diagnostic reagent and pharmaceutical compounds applications.

• E2M - 전기 전자와 첨단 소재
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• 제8권3호
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• pp.272-277
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• 1995

We report the properties of optically pumped stimulated emission at room temperature (RT) from column-III nitride semiconductors of GaN, AlGaN/GaN double heterostructure (DH) and AlGaN/GaInN DH which prepared on a sapphire substrate using an AIN buffer-layer by the nietalorganic vapor phase epitaxy (MOVPE) method. The peak wavelength of the stimulated emission at RT from AIGaN/GaN DH is 369nm and the threshold of excitation pumping power density (P$\_$th/) is about 84kW/cm$\^$2/, and they from AlGaN/GaInN DH are 402nm and 130kW/cm$\^$2/ at the pumping power density of 200kW/cm$\^$2/, respectively. The P$\_$th/ of AIGaN/GaN and AlGaN/GaInN DHs are lower than the single layers of GaN and GaInN due to optical confinement within the active layers of GaN and GaInN, respectively.

• 한국식품영양학회지
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• 제13권2호
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• pp.118-124
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• 2000

Lipoxygenase(LOX) in soybeans is responsible for beany flavors which limit the wide utilization of soybeans to foods. This study was conducted to analyze beany flavor compounds of the normal Hwagkeumkong and LOX-deficient soybean cultivars, Jinpumkong which lacks L-2, L-3, and Jinpumkong 2 which lacks all L-1, L-2, L-3. Using the combination of dynamic headspace sampling and gas chromatography-mass selective detector(DHS-GC-MSD) for analyzing volatile compounds, hexanal and hexanol were identified in whole soy flour of all three soybena cultivars. Hwangkeumkong had more volatile compounds than Jinpumkong and Jinpumkong 2 in defatted soy flour. Hexanal and acetic acid were identified in soy milk of all three soybean cultivars but Hwangkeumkong had more volatile compounds than Jinpumkong 2. From the analysis with a static headspace sampling(SHS) and GC-MSD the major compounds were hexanal, acetic acid, 1-hexanol, and 1-octen-3-ol. The content of acetic acid was similar among three cultivars. But contents of hexanal and pentanal in Jinpumkong 2 were less than that of Jinpumkong and Hwangkeumkong. Using GC-FID, Jinpumkong 2 had less contents of hexanal and pentanol than Hwangkeumkong in whole soy flour and defatted soy flour. In this study, LOX-deficient soybean cultivars showed less hexanal, pentanol and other compounds than the normal Hwangkeumkong. However quite amount of beany flavor compounds were identified in Jinpumkong and Jinpumkong 2. So further studies are required to characterize LOX isozymes, to understand the mechanisms of beany flavors production, and to develop some other methods for removing beany flavor.

• 한국공간구조학회논문집
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• 제12권4호
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• pp.91-98
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• 2012

As the occurrence rate of terror and hazard is increasing throughout the world, GSA, DoD, and FEMA are proceeding a study about mitigating the damage of terror. Korea is no more a safe place from the terrorist's threat, so we need to make measures against them. In this study we developed modified RVS System by revising some items to adjust the system to the domestic condition and conducted a risk assessment on several tall buildings in Korea. By using IRVS system which is developed by DHS, we also carried out the risk assessment. Comparing the results between RVS with IRVS, we performed terror risk evaluation of tall buildings. Through risk assessment of several tall buildings, we analyzed key factors of each scenarios and suggested the mean value of each items, so we would like to help the counter-terrorism in the design phase.

• 한국안전학회지
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• 제27권3호
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• pp.77-82
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• 2012

The leakage of toxic chemicals impact seriously on human being and environment, therefore during their treatment process, a proper management system is necessary to control their toxic effect. This study was designed to suggest the management regulation that supports business managers and facilities management. There are no extra regulation to control emergency accidents and terrors in chemical facilities. Developed countries like USA operate the management standards to control the toxic chemical and facilities according to their toxicity and processes. In order to solve this problem, we have analysed the advanced nations standard methods of security in chemical plants to study the new security management regulation which helps to prevent the chemical accidents. Especially, in USA, CCPS (Center for Chemical Process Safety), SVA (Security Vulnerability Assessment) and RBPSs (Risk-Based Performance Standards) of DHS (Department of Homeland Security) were invest I gated. On the basis of the results, we have suggested the application methods of the security and safety regulation in Korea.

• 융합보안논문지
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• 제9권1호
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• pp.29-37
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• 2009

미국은 국토안보부에서 '국토안보법'에 근거하여 공공과 민간부문 전체에 걸쳐 사이버공격과 그로 인한 위기사태를 예방하고 대응하기 위한 실질적인 조치들을 수행한다. 한국의 경우 공공분야와 민간분야에 따라 또는 주요정보통신기반시설 여부에 따라 적용 법령 및 주관기관이 달라지는 형태를 갖는다. 본 논문에서는 미국의 일원화된 사이버 위기관리 체계의 소개를 통해 우리나라 사이버 위기관리 체계 수립에 있어서 통합적이며 조직적으로 이루어지는 것이 예방의 효율성과 대응의 적시성 등에 있어 바람직함을 일깨우고자 한다.

• Plant Breeding and Biotechnology
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• 제5권3호
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• pp.204-212
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• 2017

There is a growing preference for using doubled haploids (DHs) in maize breeding programs because they reduce the time required to generate and evaluate new lines to 2 years or less. However, there is an urgent need for efficient techniques that accurately discriminate between haploid and diploid maize kernels. Here, we investigate the effects of several hormones and chemicals on the germination of haploid and diploid maize kernels, including auxin, cytokinin, ethylene, abscisic acid (ABA) biosynthesis inhibitor (fluridone), ABA catabolism inhibitor (diniconazole), methyl jasmonate (MeJA), and NaCl. Ethylene effectively stimulated the germination of both haploid and diploid maize kernels. The ABA biosynthesis inhibitor fluridone, the ABA catabolism inhibitor diniconazole, and MeJA selectively stimulated the germination of haploid maize kernels. By contrast, gibberellin, 1-naphthaleneacetic acid (NAA), kinetin, and NaCl inhibited the germination of both haploid and diploid maize kernels. These results indicate that the germination of haploid maize kernels is selectively stimulated by fluridone and diniconazole, and suggest that ABA-mediated germination of haploid maize kernels differs from that of diploid maize kernels and other plant seeds.

• 한국정보통신학회논문지
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• 제15권7호
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• pp.1613-1620
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• 2011

CSD는 미국 국토안보부(DHS)에서 제시한 IEEE Standard 802.15.4b를 토대로 하는 컨테이너 보안 장치로 ISO 668 표준 규격으로 제작된 컨테이너에 장착되어 컨테이너 도어의 개폐여부를 감지하는 장치이다. 본 연구에서 개발한 CSD(Container Security Device)의 주 기능은 컨테이너 도어 개폐 여부 감지와 컨테이너 내부 환경 상태 및 운송 도중 컨테이너에 가해지는 충격에 대한 이력 조회이다. 본 논문에서는 글로벌 물류 패러다임 변화를 토대로 컨테이너화물 안전수송에 질적 서비스 향상을 위하여 본 연구에서 개발한 ConTracer를 활용하여 구현된 시스템을 한국 일본 간 컨테이너 물류 경로에 시범 운영 테스트를 적용하여 ConTracer의 시스템 성능 평가를 검증하는데 초점을 두었다.

• 한국통신학회논문지
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• 제35권2B호
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• pp.244-251
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• 2010

CSD는 미국 국토안보부(DHS)에서 제안한 Active RFID를 기반으로 하는 컨테이너 보안 장치로 컨테이너 내부에 장착되어 컨테이너 도어의 개폐여부를 감지하는 장치이다. ConTracer는 본 연구에서 개발한 CSD(Container Security Device)로 이 장비의 주기능은 컨테이너 도어 개폐 여부 감지뿐만 아니라 온도, 습도, 충격 센서를 장착하여 컨테이너 내부 환경 상태 및 운송 도중 컨테이너에 가해지는 충격에 대한 이력 조회가 가능하다. 그리고 RFID 동작주파수는 433MHz와 2.4GHz의 두 주파수 대역을 사용하여 각 국가별 주파수 사용제안에 능동적으로 대응 할 수 있도록 하였다. 본 논문에서는 컨테이너 보안 장치의 발전 방향에 대해서 알아본 후 본 연구에서 개발한 ConTracer와 각 회사에서 개발한 CSD를 비교하여 보고, ConTracer를 이용하여 설계 및 구현한 CSD 시스템을 소개한다. 마지막으로 구현된 CSD 시스템은 한국 중국 간 컨테이너 물류에 시범서비스를 실시하여 구현한 CSD 시스템을 검증 하였다.

• 한국임상수의학회지
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• 제34권6호
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• pp.441-444
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• 2017

A 15-year-old spayed female Miniature Schnauzer was presented for unilateral foreleg lameness and pain. On physical examination, left elbow joint swelling and stiffness were identified. On a computed tomography (CT) scan, a periosteal reaction of the left humerus from the distal metaphysis to the epiphysis and cortical destruction of the medial condyle was observed. Based on blood tests, histopathology, and immunohistochemistry, it was concluded as a skeletal histiocytic sarcoma. Since the patient's pain was not controlled despite application of a fentanyl patch, a left forelimb amputation was decided upon as part of the palliative therapy. Metronomic chemotherapy with toceranib phosphate and pamidronate was initiated. Toceranib was administered for 3 months without the development of any adverse effects except mild neutropenia. However, 3 months after initiating treatment, the toceranib was discontinued due to moderate gastrointestinal disturbances. Over the next 2 months, a left mandibular bone mass and cortical bone destruction in the bilateral tibia and tarsal joint were identified on CT. The patient became unwilling to eat and was noted to have severe skeletal pain. The anorexia and lethargy were progressively worsening and the owner decided to euthanize the patient. A necropsy was performed and the patient was definitively diagnosed with disseminated histiocytic sarcoma based on histopathologic and immunohistochemical analyses. This report describes a Miniature Schnauzer dog with DHS managed with surgical removal and metronomic chemotherapy with toceranib that survived with an improved quality of life for 7 months.