• 한국산업보건학회지
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• 제9권1호
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• pp.23-40
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• 1999

The analysis of thiodiglycolic acid in urine has been used as an index of biological exposure to vinyl chloride. Unfortunately thiodiglycolic acid has a strong hydrophilic character, because it has two carboxylic groups, so that it can only be extracted with organic solvent with a great difficulty. Underivatized thiodiglycolic acid tends to tail because of non-specific interaction with the inert support. Therefore, esterification is the obvious first choice for derivatization of thiodiglycolic acid, particularly for gas chromatography. In this study, the focus of interest is to compare two method of esterifications (methylation and silylation). Methylation is to make the methyl ester of thiodiglycolic acid by reaction with diazomethane. Silylation is to make the trimethylsilyl ester of thiodiglycolic acid by reaction with N-trimethylsily-ldiethylamine. The results and conclusions are as the following: 1. The detection limit (sensitivity) of methylated thiodiglycolic acid was $5.00{\mu}g/m{\ell}$ and silylated thiodiglycolic acid was $3.07{\mu}g/m{\ell}$ by gas chromatography with flame ionization detector. 2. The optimal liquid-liquid extraction of thiodiglycolic acid was as following: To each of the tubes, $15m{\ell}$ of urine, concentrated sulfuric acid (pH 1 - 2) and 5 gsodium sulfate were added. The samples was extracted three times with $5m{\ell}$ ethylacetate each time. 3. The methylated thiodiglycolic acid was more stable than silylated thiodiglycolic acid in extractional solvent which contained humidity. 4. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.07324 in methylated thiodiglycolic acid with external standard calibration, and 0.07033 in methylated thiodiglycolic acid with internal standard calibration. 5. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.10914 in silylated thiodiglycolic acid with external standard calibration, and 0.13602 in silylated thiodiglycolic acid with internal standard calibration. From the above results, the analysis of methylated thiodiglycolic acid was more sensitive (limit of detection) than silylated thiodiglycolic acid by gas chromatography. However, the methylated thiodiglycolic acid was stable in the humidity and was separated sharply on chromatogram. Also, analysis of methylated thiodiglycolic acid was more precise (pooled coefficient of variation for 4 days) than silylated thiodiglycolic acid. In conclusion, it is established that the analysis of methylated thiodiglycolic acid is appropriate for biological monitoring of exposure to vinyl chloride.

• 생명과학회지
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• 제25권12호
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• pp.1362-1369
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• 2015

본 연구는 열수 추출된 복분자 분말을 김치두루치기에 첨가한 후 저온저장에 따른 품질 안정성을 평가하기 위해 수행되었다. 복분자 추출물의 DPPH와 수퍼옥사이드 라디칼 소거 활성은 70.63%와 57.87%로 각각 비교적 높게 나타났다. 샘플은 대조구(무처리), T1 (15% 복분자 추출물), T2 (30 복분자 추출물), T3 (0.5% 아스코르빅산; 양성대조구)를 첨가하여 제조하였다. 복분자 추출물 첨가 샘플은 대조구와 양성 대조구에 비교하여 저장 기간에 따라 pH는 온화하게 변화되는 것으로 나타났고, 대조구에 비교하여 보수력이 개선되었다. 육색은 대부분 시간 경과가 될수록 증가되는 경향성을 보였으며, 대조구보다 더 낮은 변화의 폭을 보였다. 지질 과산화는 저장일수와 처리에 상관없이 거의 변화가 없는 것으로 나타났으며, 단백질 변패도는 대조구에 비교하여 낮은 것으로 나타났다. 관능분석 결과 T1과 T2는 대조구와 양성대조구에 비교하여 더 좋은 맛과 풍미를 가지며, 전체 기호도가 더 좋은 것으로 나타났다. 따라서 복분자 첨가 김치 두루치기는 제품의 저장 안정성을 개선하고, 제품의 기호도를 개선하는 것이 가능한 것으로 제의된다.

• Parasites, Hosts and Diseases
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• 제52권3호
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• pp.305-310
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• 2014

Ascidian soft tunic syndrome (AsSTS) caused by Azumiobodo hoyamushi (A. hoyamushi) is a serious aquaculture problem that results in mass mortality of ascidians. Accordingly, the early and accurate detection of A. hoyamushi would contribute substantially to disease management and prevention of transmission. Recently, the loop-mediated isothermal amplification (LAMP) method was adopted for clinical diagnosis of a range of infectious diseases. Here, the authors describe a rapid and efficient LAMP-based method targeting the 18S rDNA gene for detection of A. hoyamushi using ascidian DNA for the diagnosis of AsSTS. A. hoyamushi LAMP assay amplified the DNA of 0.01 parasites per reaction and detected A. hoyamushi in 10 ng of ascidian DNA. To validate A. hoyamushi 18S rDNA LAMP assays, AsSTS-suspected and non-diseased ascidians were examined by microscopy, PCR, and by using the LAMP assay. When PCR was used as a gold standard, the LAMP assay showed good agreement in terms of sensitivity, positive predictive value (PPV), and negative predictive value (NPV). In the present study, a LAMP assay based on directly heat-treated samples was found to be as efficient as DNA extraction using a commercial kit for detecting A. hoyamushi. Taken together, this study shows the devised A. hoyamushi LAMP assay could be used to diagnose AsSTS in a straightforward, sensitive, and specific manner, that it could be used for forecasting, surveillance, and quarantine of AsSTS.

• 한국버섯학회지
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• 제11권2호
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• pp.53-62
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• 2013

A total of 35 phosphate solubilizing bacterial strains were isolated from waste mushroom bed of Agaricus bisporus in Buyeo-Gun, Chungnam and screened for the production of indole acetic acid (IAA). The best IAA producing strain was identified as Pantoea rodasii using 16S rRNA analysis. In addition to the IAA production, this strain could act as an efficient phosphate solubilizer (1100 ${\mu}g$ $ml^{-1}$ after 5 days of incubation) also. The selected strain was cultured under different conditions in order to assess the optimum conditions for maximum IAA production. The nutrient broth (NB) medium was recorded as the best medium, where the maximum IAA production (229 ${\mu}g$ $ml^{-1}$) was recorded at the start of stationary phase (12 hours after inoculation) of the bacteria growth. The performance of the strain was found to be maximum at the temperature of $30^{\circ}C$ followed by $25^{\circ}C$. IAA production was found to be increased with increasing tryptophan concentration (from 0.1 to 0.6%), however beyond this limit, a slight reduction in IAA production was observed. The strains' ability to produce IAA was further confirmed by extraction of crude IAA and subsequent TLC analysis. A specific spot from the extracted IAA preparation was found corresponding with the standard spot of IAA with same $R_f$ value. The results of HPLC analysis conducted in identifying and quantifying the IAA production more precisely, are in agreement with the results of the assessment done with colorimetric method. As revealed by the results of the pot experiment, the isolated strain could significantly enhance the growth (as measured by shoot and root growth) of mung bean plants compared to that of non-inoculated plants. Therefore it can be concluded that the present strain, Pantoea rodasii has great potential to be used as bio-inoculants.

• 미생물학회지
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• 제43권3호
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• pp.201-209
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• 2007

송이 자생군락 토양 내 세균군집의 정량적 평가를 수행한 결과 CFDA 형광염색법을 이용해 직접 계수된 생균수는 $7.4{\pm}1.19{\times}10^8{\sim}1.07{\pm}0.17{\times}10^9cells/g$ soil로 육즙영양배지(nutrient broth, NB)에서 배양된 생균수는 CFDA 계수치의 $5{\sim}8%$로 계수되었으며, $10^{-2}$으로 희석한 NB(DNB)배지에서는 $40{\sim}47%$의 계수치를 나타내었다. 이상의 결과로부터 송이 자생군락 토양내에는 배양이 곤란한 난배양성(viable but non-culturable; VBNC)세균이 다수 존재해 있는 것으로 추정되었다. 송이 자생군락 토양내 세균군집의 계통학적 특성을 검토하기 위해 토양으로부터 직접 DNA를 추출하고 16S rDNA-ARDRA cluster 분석을 통하여 대표 clone의 16S rDNA 염기서열 분석을 수행하였다. 송이 자생군락 토양으로부터 구축된 총 115 clone은 31 ARDRA cluster로 분류되었으며, ${\alpha}-,\;{\beta}-,\;{\gamma}-$ Proteobacteria, Acidobacteria, Actinobacteria 그리고 Firmicutes의 6개 계통군이 확인되었다. 이들 계통군 중 약 85%가 Acidobacteria 계통군에 속하여 압도적인 우점군임이 확인되어 매우 독특한 계통학적 특성을 나타내었다.

• International Journal of Automotive Technology
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• 제4권2호
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• pp.77-86
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• 2003

How to compare the environmental damage caused by vehicles with different foe]s and drive trains\ulcorner This paper describes a methodology to assess the environmental impact of vehicles, using different approaches, and evaluating their benefits and limitations. Rating systems are analysed as tools to compare the environmental impact of vehicles, allowing decision makers to dedicate their financial and non-financial policies and support measures in function of the ecological damage. The paper is based on the "Clean Vehicles" research project, commissioned by the Brussels Capital Region via the BIM-IBGE (Brussels Institute for the Conservation of the Environment) (Van Mierlo et at., 2001). The VriJe Universiteit Brussel (ETEC) and the universite Libre do Bruxelles (CEESE) have jointly carried out the workprogramme. The most important results of this project are illustrated in this paper. First an overview of environmental, economical and technical characteristics of the different alternative fuels and drive trains is given. Afterward the basic principles to identify the environmental impact of cars are described. An outline of the considered emissions and their environmental impact leads to the definition of the calculation method, named Ecoscore. A rather simple and pragmatic approach would be stating that all alternative fuelled vehicles (LPG, CNG, EV, HEV, etc.) can be considered as ′clean′. Another basic approach is considering as ′clean′ all vehicles satisfying a stringent omission regulation like EURO IV or EEV. Such approaches however don′t tell anything about the real environmental damage of the vehicles. In the paper we describe "how should the environmental impact of vehicles be defined\ulcorner", including parameters affecting the emissions of vehicles and their influence on human beings and on the environment and "how could it be defined \ulcorner", taking into account the availability of accurate and reliable data. We take into account different damages (acid rain, photochemical air pollution, global warming. noise, etc.) and their impacts on several receptors like human beings (e.g., cancer, respiratory diseases, etc), ecosystems, or buildings. The presented methodology is based on a kind of Life Cycle Assessment (LCA) in which the contribution of all emissions to a certain damage are considered (e.g. using Exposure-Response damage function). The emissions will include oil extraction, transportation refinery, electricity production, distribution, (Well-to-Wheel approach), as well as the emission due to the production, use and dismantling of the vehicle (Cradle-to-Grave approach). The different damages will be normalized to be able to make a comparison. Hence a reference value (determined by the reference vehicle chosen) will be defined as a target value (the normalized value will thus measure a kind of Distance to Target). The contribution of the different normalized damages to a single value "Ecoscore" will be based on a panel weighting method. Some examples of the calculation of the Ecoscore for different alternative fuels and drive trains will be calculated as an illustration of the methodology.

• 한국정보과학회논문지:소프트웨어및응용
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• 제34권3호
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• pp.226-234
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• 2007

본 논문은 환경 노이즈를 원천적으로 차단하는 성대 마이크를 이용한 명령어 인식기를 개발한다. 성대마이크는 환경 노이즈의 효과를 최소화하는 장점이 있다. 그러나 고주파의 부재와 부분적인 포먼트 정보 손실 때문에, 성대마이크를 이용해서 개발된 ASR시스템은 표준마이크를 이용한 시스템에 비해 낮은 성능을 보인다. 이러한 문제 때문에 ASR시스템 개발에 성대마이크를 이용한 경우는 표준 마이크로 낮은 성능을 보인다. 이러한 문제 때문에 ASR시스템 개발에 성대마이크를 이용한 경우는 표준 마이크로부터 입력되는 정보 보안하는데 주로 사용된다. 본 논문은 한국어의 음운적 특정과 신호 분석을 통해 성대마이크만을 사용한 높은 성능의 ASR 시스템을 개발 할 수 있음을 보인다. 주파수 대역내 에너지 합을 이용하는 MFCC 알고리즘이 갖는 성대신호 분석의 문제점을 제시하고, 성대신호를 대상으로 보다 높은 성능을 갖는 특정추출 알고리즘의 조건을 제시한다. 이러한 조건은 (1) 민감한 band-pass filter와 (2) 유/무성음 분리를 위해 사용하는 특정벡터의 사용이다 실험 결과 제안된 조건을 만족하는 ZCPA 알고리즘을 적용한 경우가 MFCC를 적용한 경우보다 약 16%정도의 높은 성능을 보인다. 그러고 CMS와 RASTA와 같은 channel normalization 알고리즘을 적용한 경우 약 2%의 성능 향상이 있다.

• 한국식품과학회지
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• 제19권6호
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• pp.499-505
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• 1987

루우핀콩 단백질 농축물(LPC-50, LPC-70)을 제조하여 이들의 식품기능성들을 분리대두단백질 및 카제인 과 비교 검토하였다. LPC-50은 2상용매 추출법에 의해 제조한 단백질 함량 50% 수준의 유백색 물질이며 LPC-70은 LPC-50의 탄수화물 일부를 가수분해 효소로 처리해서 제거하여 단백질 농도를 70% 수준으로 높인 것이다. LPC-50의 건물 수율은 73.7%였으며 LPC-70은 55.7%였다. 또한 단백질 수율면에서는 LPC-50이 91% 였고 LPC-70이 87.4%였다. LPC-50과 LPC-70의 단백질 용해도는 증류수에서는 SPI와 비슷한 경향이 보였으나, NaCl 첨가시 pH $4.0{\sim}6.0$ 범위에서는 SPI보다 높았다. LPC-50과 LPC-70의 흐름성질은 8% 농도에서 강한 의가소성을 보였으며. 겉보기 점도는 6%부터 지수적으로 증가하였으며 그 증가 패턴은 카제인과 비슷한 경향이었다. 유화력은 단백질 농도가 증가할수록 커졌으며, LPC-70은 우수한 유화력을 나타내었고 특히 NaCl 첨가시 SPI와 비슷한 유화력을 나타내었다. LPC-50과 LPC-70의 기포 형성력은 SPI의 기포 형성력과 비슷하였으나, 안정성이 pH 7.0에서 비교적 낮은 결과를 보였다. 루우핀콩 단백질 농축물들은 우수한 수분 및 유지 흡착력을 나타냈으며, 특히 LPC-70은 매우 높은 유지 흡착력을 보였다.

• Imaging Science in Dentistry
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• 제50권3호
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• pp.199-208
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• 2020

Purpose: This study was performed to introduce an in vivo hybrid multimodality technique involving the coregistration of micro-computed tomography (micro-CT) and high-resolution magnetic resonance imaging (HR-MRI) to concomitantly visualize and quantify mineralization and vascularization at follow-up in a rat model. Materials and Methods: Three adult female rats were randomly assigned as test subjects, with 1 rat serving as a control subject. For 20 weeks, the test rats received a weekly intravenous injection of 30 ㎍/kg zoledronic acid, and the control rat was administered a similar dose of normal saline. Bilateral extraction of the lower first and second molars was performed after 10 weeks. All rats were scanned once every 4 weeks with both micro-CT and HR-MRI. Micro-CT and HR-MRI images were registered and fused in the same 3-dimensional region to quantify blood flow velocity and trabecular bone thickness at T0 (baseline), T4 (4 weeks), T8 (8 weeks), T12 (12 weeks), T16 (16 weeks), and T20 (20 weeks). Histological assessment was the gold standard with which the findings were compared. Results: The histomorphometric images at T20 aligned with the HR-MRI findings, with both test and control rats demonstrating reduced trabecular bone vasculature and blood vessel density. The micro-CT findings were also consistent with the histomorphometric changes, which revealed that the test rats had thicker trabecular bone and smaller marrow spaces than the control rat. Conclusion: The combination of micro-CT and HR-MRI may be considered a powerful non-invasive novel technique for the longitudinal quantification of localized mineralization and vascularization.

• 한국통신학회논문지
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• 제36권6C호
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• pp.349-354
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• 2011

수동형(passive) 밀리미터파(millimeter wave) 영상은 의복 등에 은닉된 물체의 탐지가 가능하며 악천후의 상황에서도 감쇄도(attenuation)가 낮아 식별이 가능한 영상을 획득할 수 있다. 그러나 영상 시스템의 공간 해상도(spatial resolution)가 낮고 수신신호가 미약하여 잡음의 영향이 크고 시스템의 온도 분해능(temperature resolution)에 따라 영상의 질이 달라진다. 본 논문에서는 수동형 밀리미터파 영상과 일반 카메라부터 획득되는 영상의 정합(registration)과 은닉된 물체의 시각화를 위한 영상 융합(fusion)을 연구한다. 영상의 정합은 추출된 몸체 경계 간의 상호상관도를 최대로 하는 어파인 변환(affine transform)으로 수행되며 융합은 영상 분해를 위한 이산 웨이블릿 변환(discrete wavelet transform), 융합 법칙(fusion rule), 영상을 복원하기 위한 역 이산 웨이블릿 변환의 3단계로 구성된다. 실험에서는 수동형 밀리미터파 영상 시스템에 의해 칼, 도끼, 화장품, 그리고 휴대폰과 같은 또는 비금속의 다양한 물체가 탐지됨을 보인다. 또한 정합과 융합된 영상의 결과로부터 가시 영상으로부터 얻은 얼굴과 의복 등의 대상자의 신원정보와 밀리미터파 영상으로부터 획득한 은닉된 물체의 정보를 동시에 시각화할 수 있음을 보인다.