• 농약과학회지
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• 제8권2호
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• pp.117-128
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• 2004

농약 등 화학물질의 생태독성평가에서 주요 이용되는 수서무척추동물로 국제적으로 추천하고 있는 물벼룩은 D. magna이다. 하지만 D. magna는 국내에 서식하지 않는 종이므로 우리나라 환경에 적합한 생태 위해성평가를 위해서는 국내에 서식하는 대표종에 대한 독성시험법을 개발할 필요가 있다. 따라서 본 연구는 국내에 서식하는 물벼룩 중에 농업환경에서의 대표종 4종(Daphnia obtusa, Daphnia sp., Moina macrocopa, Simocephalus vetulus)을 선정하여 이들 종에 대한 최적실내사육조건을 확립하고자 3종의 조류를 배양한 후 냉장보관 하면서 먹이의 종류 및 양에 따른 물벼룩의 생육특성을 조사하였다. 그 결과 시험에 사용된 국내산 물벼룩은 국제적인 추천종인 D. magna에 비해 먹이의 양이 절반 정도 수준에서도 잘 생육하는 것으로 조사되었고 특히 Chlorella가 가장 적합한 먹이인 것으로 나타났는데, Chlorella의 최적 투여농도는 $25\times10^4\sim50\times10^4$cells/mL 이었다.

• Journal of Applied Biological Chemistry
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• 제55권4호
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• pp.207-215
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• 2012

유근피에 함유된 페놀성 물질은 70% ethanol을 용매로 하여 추출하였을 때 $17.9{\pm}1.0mg/g$이 용출되었다. 주름 생성과 관련된 elastase 저해 활성은 $50-200{\mu}g/mL$ phenolics 농도의 70% ethanol 추출물에서 55.5-69.5%의 제해효과를 확인할 수 있었다. 유근피 추출물의 미백효과와 관련된 tyrosinase 저해활성은 $200{\mu}g/mL$ phenolics 농도의 70% ethanol 추출물에서 24%의 저해효과가 측정되었다. Astringent 활성은 $200{\mu}g/mL$ phenolics 농도의 70% ethanol 추출물에서 71%의 활성을 나타내어 모공축소 효과가 높을 것으로 판단되었다. 유근피 추출물의 hyaluronidase 저해활성은 $50{\mu}g/mL$ phenolics의 농도에서 80%의 염증억제 효과가 확인되었다. 유근피 추출물의 항균활성은 물 추출물의 경우 $50-200{\mu}g/mL$의 phenolics 농도에서 Propionibacterium acnes에 대한 항균활성이 각각 8.7, 10, 11.1 및 11.8 mm의 clear zone이 확인되었다. 유근피 추출물을 첨가하여 제조한 복합 기능성 화장품(로션)의 안정성은 28일 동안 pH 및 점도의 변화가 없었고, 온도 및 광에 대하여 안정하였다. 제조한 로션은 추출물의 첨가 농도가 증가함에 따라 색도는 어둡게 나타났으나, 사용감면에서 8.5점 정도의 좋은 점수를 나타내었다.

• 한국농공학회논문집
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• 제59권4호
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• pp.97-107
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• 2017

This study is to determine the coefficients of regression equations and to select the optimal regression equation in the LOADEST model after classifying the whole study period into 5 flow conditions for 16 watersheds located in the Nakdonggang waterbody. The optimized coefficients of regression equations were derived using the gradient descent method as a learning method in Tensorflow which is the engine of machine-learning method. In South Korea, the variability of streamflow is relatively high, and rainfall is concentrated in summer that can significantly affect the characteristic analysis of pollutant loads. Thus, unlike the previous application of the LOADEST model (adjusting whole study period), the study period was classified into 5 flow conditions to estimate the optimized coefficients and regression equations in the LOADEST model. As shown in the results, the equation #9 which has 7 coefficients related to flow and seasonal characteristics was selected for each flow condition in the study watersheds. When compared the simulated load (SS) to observed load, the simulation showed a similar pattern to the observation for the high flow condition due to the flow parameters related to precipitation directly. On the other hand, although the simulated load showed a similar pattern to observation in several watersheds, most of study watersheds showed large differences for the low flow conditions. This is because the pollutant load during low flow conditions might be significantly affected by baseflow or point-source pollutant load. Thus, based on the results of this study, it can be found that to estimate the continuous pollutant load properly the regression equations need to be determined with proper coefficients based on various flow conditions in watersheds. Furthermore, the machine-learning method can be useful to estimate the coefficients of regression equations in the LOADEST model.

• Journal of Microbiology and Biotechnology
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• 제25권7호
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• pp.1170-1176
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• 2015

Ginsenosides, the major active component of ginseng, are traditionally used to treat various diseases, including cancer, inflammation, and obesity. Among these, compound K (CK), an intestinal bacterial metabolite of the ginsenosides Rb₁, Rb₂, and Rc from Bacteroides JY-6, is reported to inhibit cancer cell growth by inducing cell-cycle arrest or cell death, including apoptosis and necrosis. However, the precise effect of CK on breast cancer cells remains unclear. MCF-7 cells were treated with CK ($0-70{\mu}M$) for 24 or 48 h. Cell proliferation and death were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays, respectively. Changes in downstream signaling molecules involved in cell death, including glycogen synthase kinase $3\beta$ ($GSK3\beta$), $GSK3\beta$, $\beta$-catenin, and cyclin D1, were analyzed by western blot assay. To block $GSK3\beta$ signaling, MCF-7 cells were pretreated with $GSK3\beta$ inhibitors 1 h prior to CK treatment. Cell death and the expression of $\beta$-catenin and cyclin D1 were then examined. CK dose- and time-dependently inhibited MCF-7 cell proliferation. Interestingly, CK induced programmed necrosis, but not apoptosis, via the $GSK3\beta$ signaling pathway in MCF-7 cells. CK inhibited $GSK3\beta$ phosphorylation, thereby suppressing the expression of $\beta$-catenin and cyclin D1. Our results suggest that CK induces programmed necrosis in MCF-7 breast cancer cells via the $GSK3\beta$ signaling pathway.

• 유기물자원화
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• 제28권2호
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• pp.41-48
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• 2020

본 연구에서는 음식물류폐기물 건조공정에서 발생하는 응축수에 포함된 유기탄소를 추출하여 외부탄소원으로서 적용 가능성을 평가하였다. 응축수의 성상은 COD, TN, TP 및 TS는 각각 21,374 (±3,238.3) mg/L, 148 (±32.6) mg/L, 4.19 (±1.5) mg/L, 455.7 (±0.015) mg/L로 나타났으며, 응축수에 포함된 생분해성 유기물의 함량은 47%였다. 응축수에 포함된 유기탄소 추출을 위하여 증발 농축 및 감압 증발 농축의 방법을 사용하였다. 본 연구에서 총 8가지 조건에서 수행 되었으나, 4가지 조건 (1. 상압 (0mmHg), 110℃ 2. 감압 (-600mmHg), 70℃ 3. 감압 (-500mmHg), 80℃ 4. 감압(-600mmHg), 80℃)에서 추출이 가능한 것으로 나타났다. 추출 결과, 추출된 4가지 조건 모두에서 유입 부피의 약 10% 추출하였을 때, 추출물의 유기물 농도가 가장 높고 추출 시간 대비 추출된 유기물의 양이 가장 많은 것으로 나타났다. 응축수에 포함된 유기탄소의 추출 최적 조건은 감압 (-600mmHg), 80℃로 판단하였으며, 유입 부피의 10% 추출이 적합한 것으로 평가하였다. 이때, 추출 농도, 추출량, 추출 효율, 추출시간, BOD/TCOD, TVFAs/TCOD의 비율 및 NH₃-N의 값은 각각 174,200 mg/L, 8,710 mg, 46%, 10분, 0.97, 0.74, 75.5 mg/L로 나타났다. 따라서, 추출된 유기탄소는 외부탄소원으로 활용될 수 있을 것으로 판단된다.

• 농약과학회지
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• 제2권2호
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• pp.75-82
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• 1998

벼멸구의 카보후란에 대한 저항성 기작을 구명하기 위해 실내에서 카보후란으로 30세대 도태하여 얻은 저항성계통($LD_{50};\;20.3{\mu}g/g$)과 약제를 12년 동안 처리하지 않은 벼멸구 감수성 계통($LD_{50};\;0.3{\mu}g/g$)에 $^{14}C$-카보후란을 처리하여 계통 간 대사물 량의 차이를 조사한 바 카보후란의 대사물인 benzofuran과 TLC의 의해 전개되지 않은 원점 부분은 감수성 계통에서 많았으며, 대사되지 않은 카보후란은 저항성 계통에서 많았다. 이러한 경향은 처리 후 1, 3시간 대사에서도 같은 경향이었다. 이상의 결과로부터 저항성 벼멸구에서 가수 분해 효소의 일종인 에스테라제가 저항성이 발달함에 따라 에스터 결합을 끊는 역할에서 카보후란과의 결합체 역할로 그 기능이 전환되는 것으로 생각되며 이것이 저항성 기작 중 주요한 하나의 요인으로 사료된다. 산화효소와 전이효소는 저항성과 감수성 계통에서 대사물의 양에 차이가 없어 저항성과는 무관한 것으로 생각된다.

• Journal of Korean Neurosurgical Society
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• 제29권9호
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• pp.1233-1237
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• 2000

Objectives : In order to evaluate the metabolic changes associated with pericontusional edematous area in mild head injury, proton magnetic resonance spectroscopy(1H-MRS) was performed in mild head injury patients (initial GCS score 13-15) with focal brain contusion. Methods : Seven head injury patients with initial GCS 13-15(3 males and 4 females : age range 15-65 years, mean age 33 years) have underwent 1H-MRS evaluations. The patients were examined within 7 days after injury(n=7) and 2 months after injury(n=5). The region of interest(ROI) was selected in the edematous area adjacent to traumatic brain contusion upon T2-weighted MR images and a corresponding region of the contralateral hemisphere (ROC, region of contralateral corresponding hemisphere) was examined as well. The metabolic ratios of NAA/Cr and lactate/Cr were compared between ROIs, ROCs and control values. Results : In initial NAA/Cr ratios, the values of ROIs were significantly lower than those of the controls(p=0.009), but there was no difference either between ROIs and ROCs(p=0.410) or between ROCs of patients and the control (p=0.199). In lactate/Cr ratios, the ROIs in all seven patients and the ROCs in two showed increased lactate signals. The lactate/Cr ratios of the ROIs were significantly elevated as compared to those of the ROCs(p=0.02) and the control(p=0.015). In two months follow-up, lactate signals were absent or significantly reduced(p=0.015). In no patients, clinical or radiological deterioration has been observed. Conclusion : Our 1H-MRS results demonstrate that there are significant ischemic changes in pericontusional edematous areas as indicated by elevated lactate signals in the patients with mild head injury. But there were no consistent neural loss or dysfunction in these area. There findings suggest that pericontusional edematous areas can be vulnerable to secondary brain insults even in the patients with mild head injury.

• 한국대기환경학회지
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• 제29권1호
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• pp.97-104
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• 2013

Methyl alcohol is one of the basic intermediates in the chemical industry and is also being used as a fuel additive and as a clean burning fuel. In this study, conversion of carbon dioxide to methyl alcohol was investigated using catalytic chemical methods. Ceramic monoliths (M) with $400cell/in^2$ were used as catalyst supports. Monolith-supported CuO-ZnO catalysts were prepared by wash-coat method. The prepared catalysts were characterized by using ICP analysis, TEM images and XRD patterns. The catalytic activity for carbon dioxide hydrogenation to methyl alcohol was investigated using a flow-type reactor under various reaction temperature, pressure and contact time. In the preparation of monolith-supported CuO-ZnO catalysts by wash-coat method, proper concentration of precursors solution was 25.7% (w/v). The mixed crystal of CuO and ZnO was well supported on monolith. And it was known that more CuO component may be supported than ZnO component. Conversion of carbon dioxide was increased with increasing reaction temperature, but methyl alcohol selectivity was decreased. Optimum reaction temperature was about $250^{\circ}C$ under 20 atm because of the reverse water gas shift reaction. Maximum yield of methyl alcohol over CuO-ZnO/M catalyst was 5.1 mol% at $250^{\circ}C$ and 20 atm.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.588-591
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• 2018

Baculovirus는 원래 알팔파 루퍼 (looper)로부터 분리되었으며 154 개의 오픈 리딩 프레임 (ORF)을 가진 134-kbp 게놈을 포함하고 있다. 주요 캡시드 단백질 VP39는 약간의 단백질과 함께 p6.9 단백질로 DNA를 감싸는 뉴클레오 캡시드($21nm{\times}260nm$)로 형성된다. 그것들은 막대 모양의 캡시드 안에 이중 가닥의 고리 모양의 슈퍼 코일 DNA 분자이다. 야생형 baculovirus는 용균 및 폐색 된 생명주기를 모두 나타내며 바이러스 복제의 3 단계에 걸쳐 독립적으로 발달한다. 재조합 baculovirus는 광범위한 포유류 세포 유형에서 벡터를 전달하고 재조합 단백질을 발현 할 수 있다. 특히, 이들 baculovirus 벡터에 우세한 선별 마커를 포함시킴으로써 많은 세포에서 다양한 재조합 유전자를 발현시킬 수 있다. 본 연구의 배큘로 바이러스 벡터는 cytomegalovirus (CMV) 프로모터, uroplakin II promoter, polyhedron promoter, 수포 구내염 바이러스 G (VSVG), 녹색 형광 단백질 (EGFP), 단백질 전달 도메인 (PTD) 유전자 등으로 재구성되었다. 이러한 재구성 된 벡터를 다양한 세포 및 세포주에 감염시켰다. 우리는 다른 재조합 벡터와 비교하여 이러한 재조합 벡터의 전이 및 발현을 조사하는 수행하였다. 본 연구에서, 우리는 이 재조합 벡터의 형질 감염 및 발현이 어떤 대조군 벡터보다 더 높은 효능을 갖는다는 것을 알았다. 본 연구는 과학 기술부, 한국 정보 기술 진흥 기금 (MSIP)이 후원하는 한국 연구 재단 (NRF)을 통해 중견 연구원 프로그램 (NRF-2016R1A2B4016552)을 통해 지원되었다.

• 환경위생공학
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• 제22권1호
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• pp.1-16
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• 2007

The incineration process has commonly used for wastes amount reduction and thermal treatments of pollutants as the technologies accumulated. However, the process is getting negative public images owing to matter of hazardous pollutants emission. Specially dioxins became a main issue and is mostly emitted from municipal solid wastes incineration. In this reason, pyrolysis/gasfication/melting process is presented as a alternative of incineration process. The pyrolysis/gasfication/melting process, a novel technology, is middle of verification of commercial plant and development of technologies in Korea. But the survey about the pollutant emission from the process, and background data in these facilities is necessary. So in this survey, it Is investigated that the behavior of dioxins in three pyrolysis/gasfication/melting plant (S, T, P) of pilot scale. In case of S plant, concentration of dioxins shows high at latter part of cogenerated boiler and stack which are operate on low temperature conditions than a latter parts of pyrolysis and melting furnace which are operate on high temperature condition. Concentration of gas phage dioxins had increased after combusted gas passed cogenerated boiler and this is attributed to react of precursor materials such as chlorobenzene and chlorophenol. Concentration of dioxins in T plant showed lower levels at latter part of cooling equipment which are operate with water spray type on low temperature conditions than a latter parts of gasfied melting furnace which are operate on high temperature condition. Removal efficiency of dioxins at gas treatment equipment was 78.8 %. Concentration of dioxins in P plant was low at latter part of SDA/BF which is operate at low temperature conditions than a latter parts of pyrolysis gasfied chamber which are operate at high temperature condition. Removal efficiency of dioxins of SDA/BF was 85.9 % and therefore, it showed high efficiency at those of stoker type incineration facility. However, concentration of dioxins which emitted at high temperature condition were low in three facilities and satisfied present standard emission level of dioxins. To consider the distribution ratio of dioxins, Particulate phase dioxins at S and P plants showed similar ratio with which shows in current stoker type for middle scale domestic waste incineration facility. It is necessary to continuos monitoring the ratio of distribution of dioxins in T plant in because ratio of gas phage dioxins showed high.