• 한국자기공명학회논문지
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• 제19권1호
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• pp.1-10
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• 2015

Refinements with atomistic molecular dynamics (MD) simulation have contributed to improving the qualities of NMR structures. In most cases, the calculations with atomistic MD simulation for NMR structures employ generalized-Born implicit solvent model (GBIS) to take into accounts solvation effects. Developments in algorithms and computational capacities have ameliorated GBIS to approximate solvation effects that explicit solvents bring about. However, the quantitative comparison of NMR structures in the latest GBIS and explicit solvents is lacking. In this study, we report the direct comparison of NMR structures that atomistic MD simulation coupled with GBIS and water molecules refined. Two model proteins, GB1 and ubiquitin, were recalculated with experimental distance and torsion angle restraints, under a series of simulated annealing time steps. Whereas the root mean square deviations of the resulting structures were apparently similar, AMBER energies, the most favored regions in Ramachandran plot, and MolProbity clash scores witnessed that GBIS-refined structures had the better geometries. The outperformance by GBIS was distinct in the structure calculations with sparse experimental restraints. We show that the superiority stemmed, at least in parts, from the inclusion of all the pairs of non-bonded interactions. The shorter computational times with GBIS than those for explicit solvents makes GBIS a powerful method for improving structural qualities particularly under the conditions that experimental restraints are insufficient. We also propose a method to separate the native-like folds from non-violating diverged structures.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.604-609
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• 2002

The passive microwave remote sensing has progressed considerably in recent years. Important earth surface parameters are detected and monitored by airborne and space born radiometers. However the spatial resolution of real aperture measurements is constrained by the antenna aperture size available on orbiting platforms and on the ground. The inverse problem technique is researched in order to improve the spatial resolution of microwave scanning radiometer. We solve a two-dimensional (surface) temperature-imaging problem with a major intention to develop high-resolution methods. In this paper, the scenario for estimation of both radiometer point spread function (PSF) and target configuration is explained. The PSF of the radiometer is assumed to be unknown and estimated from the observations. The configuration and brightness temperature of targets are also estimated. To do this, we deal with the parametric modeling of observation scenario. The performance of developed algorithms is illustrated on two-dimensional experimental data obtained by the water vapor radiometer.

• 대한원격탐사학회지
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• 제19권1호
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• pp.53-59
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• 2003

The passive microwave remote sensing has progressed considerably in recent years Important earth surface parameters are detected and monitored by airborne and space born radiometers. However the spatial resolution of real aperture measurements is constrained by the antenna aperture size available on orbiting platforms and on the ground. The inverse problem technique is researched in order to improve the spatial resolution of microwave scanning radiometer. We solve a two-dimensional (surface) temperature-imaging problem with a major intention to develop high-resolution methods. In this paper, the scenario for estimation of both radiometer point spread function (PSF) and target configuration is explained. The PSF of the radiometer is assumed to be unknown and estimated from the observations. The configuration and brightness temperature of targets are also estimated. To do this, we deal with the parametric modeling of observation scenario. The performance of developed algorithms is illustrated on two-dimensional experimental data obtained by the water vapor radiometer.

• 사상체질의학회지
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• 제15권2호
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• pp.137-150
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• 2003

The purpose of this study is to examine the toxic effects caused by glucose oxidase (GO) and the effects of Hyungbangjihwangtang (HJT) water extracts on the treatment of the toxic effects. For this purpose, experiments with the cultured hippocampal cells from new born mice were done. The results of these experiments were as follows. 1. GO decreased the survival rate of the cultured cells on MTT assay and NR assay. 2. HJT has the efficacy of decreasing the lipid peroxidation. 3. HJT has the efficacy of increasing the amount of neurofilaments. 4. HJT has the efficacy of decreasing the activation of protein kinase C(PKC). From the above results, it is concluded that HJT has marked efficacy as a treatment for the damages caused by the GO-mediated oxidative stress. Further clinical study of this pharmacological effects of H]T should be completed.

• Pediatric Infection and Vaccine
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• 제14권1호
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• pp.111-115
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• 2007

본 저자들은 발열과 점액성 혈변을 보인 신생아에서 대변 현미경 검사를 통해 이질아메바를 진단하고 metronidazole 경구 투약 후 증상의 호전과 이질아메바의 제거를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• Nutritional Sciences
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• 제6권4호
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• pp.195-200
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• 2003

In recent years, the prevalence of type 2 diabetes mellitus has dramatically increased in Korea as the diet has rapidly become westernized. We determined the effect of long-term cola intakes on glucose metabolism and oxidative stress in weanling male Sprague Dawley rats consuming a moderate fat diet Thirty male rats, born from 6 female rats, were randomized into cola or water drinking groups. For 28 weeks, all rats were provided with an ad lib solid diet having 33 percent of its metabolisable energy as fat In addition, rats of the cola group were provided with ad lib cola instead of water. The daily total caloric intake did not differ between groups. The rats in the cola group consumed a higher proportion of carbohydrates, and their mean body weight and fasting serum insulin level were lower than that of the control group. Whole-body glucose disposal rates measured by an euglycemic hyperinsulinemic clamp were higher in the cola group. However, lipid peroxide levels in kidney tissue were higher in the cola group than in the control group. Superoxide dismutase activity in kidney tissues was lower in the cola group compared to the control group, while glutathion peroxidase and catalase activities were not significantly different between the two groups. In conclusion, long-term cola intakes decreased insulin resistance, but increased oxidative stress in kidney tissue due to decreased SOD activities, which may lead to kidney damage. Thus, moderate changes in insulin resistance may not affect the status of oxidative stress, and vice versa.

• 한국식품저장유통학회지
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• 제11권3호
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• pp.319-324
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• 2004

감귤과피의 열수, 에탄을 및 설탕 추출방법에 따른 항균활성을 비교 조사하였다 그 결과 감귤껍질의 열수 및 에탄올 추출물에서는 항균활성이 나타나지 않았으나, 설탕추출물에서 높은 항균활성을 나타내었다. 10$\%$(w/v) 설탕용액에서 9일간 추출하였을 때 8종의 균주 모두에서 항균활성이 가장 높았다 또한 최소저해농도는 S. aureus에서 0.5$\%$(v/v), B. subtilis, M. luteus 및 E. coli는 1.5%(viv), S. mutans는2.0$\%$(v/v) 각각 나타났다. 감귤 껄질 추출물은 40$\~$100$^{\circ}C$, 1시간 처리범위에서 항균성은 매우 안정하였으나, pH의 변화에서는 불안정하게 나타났다. 이상의 결과로 감귤껍질 추출물은 열안정성이 높은 항균성 소재로 개발이 기대되었다.

• 한국식품영양과학회지
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• 제33권3호
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• pp.500-504
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• 2004

산초는 우리나라를 비롯한 일본, 중국 등지 에 널리 분포하고 있으며 전통적으로 우리 정서에 친숙한 식미와 향기를 가지는 아시아권의 공통적인 향신료이다. 더불어 우리나라에서는 생선회와 어패류의 소비가 증가함에 따라 Vibrio parahaemolyticus에 의한 식중독발생 억제방안의 확립이 필요한 실정이다. 따라서 본 연구는 독성이 없는 새로운 천연 식품 보존제의 개발을 위하여 식품 및 향신료로서 적용 범위가 광범위한 산초를 대상으로 Vibrio parahaemolyticus에 대한 천연항균제의 적용 가능성을 검토하였다. 산초나무 추출물의 항균작용을 알아보기 위해서 Vibrio parahaemolyticus에 대한 항균력 분석에서 종자를 제외한 성분으로 제조한 산초의 주정추출물이 효과가 가장 우수함을 확인하였으며, 이 추출물의 온도 및 pH에 대한 안정성을 검토한 결과 다양한 범위의 온도, pH에 대해서 매우 안정하다는 것을 알 수 있었다. 또한 GC-MS에 의한 산초 추출물의 분리, 동정 결과에서는 estragole이 항균활성을 나타내는 주성분임을 확인하였다. 이 결과를 바탕으로 우리나라에서 많이 사용되는 산초를 Vibrio parahaemolyticus에 의한 식중독을 줄일 수 있는 항균제로 적용할 수 있음을 확인할 수 있었다. 따라서 식품첨가제 및 포장재, 식품포장 외부 충진 물질, 살균소독제 등의 다양한 형태로의 응용이 가능하리라 생각된다.

• 동아시아식생활학회지
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• 제10권2호
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• pp.160-169
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• 2000

This study was conducted to understand the inhibitory garlic and ginger against the growth of food born pathogenic bacteria. Juice was prepared from the raw spices by using an electric homogenizer and membrane filter. Dry-powdered spices were treated with double distilled water and 70% ethanol to extract the antibacterial substances, respectively. Growth inhibitory effects of juice and extracts of the spices were monitored by using bacterial strains such as B. subtilis, L. moncytogenes, S. aureus,E. coli O157 : H7, P. aeruginosa, and S. typhimurium. On a solid medium where E. coli and S. aureus cells were grown, ginger juice formed inhibitory zone at the concentrations of 2-10% by paper disc test. The Bone formed by ginger juice was wider and more transparent than that formed by garlic juice on the same concentration.1. monocytogenes and B. subtilis were more sensitive to garlic juice than others, and stopped growing at 2% garlic juice. Ginger juice showed the growth inhibition by 30-50% at 1.0% concentration. On the contrast, P. aeruginosa which resisted to the garlic juice was the most sensitive to ginger juice. Water extract of garlic was not effective to inhibit the bacterial growth, while 2% ginger extract completely inhibited the growth of E. coli and S. aureus. Alcohol extract of ginger inhibited the growth of bacteria at the concentration of 0.3%. This growth inhibition is almost 10 times lower than that of the garlic extract. It was clear that ginger had more potential than garlic as an inhibitor to control the growth of the indicator organisms.

• 접착 및 계면
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• 제13권2호
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• pp.64-72
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• 2012

비닐아세테이트와 알킬아크릴레이트계 에멀젼공중합에서 개시제인 ammonium persulfate (APS)의 농도, 보호 콜로이드인 poly(vinyl alcohol) (PVA)의 종류와 농도, 공단량체인 methyl acrylate (MA), ethyl acrylate (EA), n-butyl acrylate (BA)의 혼합비를 변화시켜 중합하였다. 제조된 poly(vinyl acetate-co-methyl acrylate) (PVAc/PMA), poly(vinyl acetate-co-ethyl acrylate) (PVAc/PEA), poly(vinyl acetate-co-n-butyl acrylate) (PVAc/PBA)에 대하여 다음과 같은 결론을 얻었다. 등온 열분해법으로 $100{\sim}200^{\circ}C$ 영역에서 구한 비닐아세테이트와 알킬아크릴레이트 공중합체에 대한 등온 열분해 활성화에너지는 PVAc/PMA > PVAc/PEA > PVAc/PBA이었으며, 플라스마 처리 전과 후의 접착박리강도는 PVAc/PMA > PVAc/PEA > PVAc/PBA의 순이었다.