• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.261-261
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• 2006

Membranes are a central feature of all biological systems and their ability to control many cellular processes is critically important. As a result, a better understanding of how molecules bind to biological membranes is an active area of research. In this report, the interaction between our biomimetic structures and different biological membranes is reported using both model vesicle and in vitro bacterial cell experiments. These results show that lipid composition is more important for selectivity than overall net charge. An effort is made to connect model vesicle studies with in vitro data and naturally occurring lipid compositions.

• Fisheries and Aquatic Sciences
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• 제26권4호
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• pp.268-281
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• 2023

Coral reef fisheries are prominent for the archipelagic countries' food sufficiency and security. Studies showed that fish abundance and biomass are affected by biophysical variables. The present study determines which biophysical variables are important predictors of fish diversity, abundance, and biomass. The study used available monitoring data from the Indonesian Research Center for Oceanography, the National Board for Research and Innovation. Data were collected from 245 transects in 19 locations distributed across the Indonesian Archipelago, including the eastern Indian Ocean, Sunda Shelf (Karimata Sea), Wallacea (Flores and Banda Seas), and the western Pacific Ocean. Principal component analysis and multiple regression model were administered to 13 biophysical metrics against 11 variables of coral reef fishes, i.e., diversity, abundance, and biomass of coral reef fishes at three trophic levels. The results showed for the first time that the covers of other fauna, coral rubbles, and soft corals were the three most important predictor variables for nearly all coral reef fish variables. Other fauna cover was the important predictor for all 11 coral reef fish variables. Coral rubble cover was the predictor for ten variables, but carnivore fish abundance. Soft coral cover was a good predictor for corallivore, carnivore, and targeted fishes. Despite important predictors for corallivore and carnivore fish variables, hard coral cover was not the critical predictor for herbivore fish variables. The other important predictor variables with a consistent pattern were dead coral covered with algae and rocks. Dead coral covered with algae was an important predictor for herbivore fishes, while the rock was good for only carnivore fishes.

• 한국가시화정보학회지
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• 제16권1호
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• pp.15-20
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• 2018

For the measurement of biophysical properties related with cardiovascular diseases (CVD), various microfluidic devices were proposed. However, many devices were monitored by optical equipment. Ultrasound measurement to quantify the biophysical properties can provide new insights to understand the cardiovascular diseases. This study aims to check feasibility of microfluidic device for ultrasound image analysis based on 3D printer. To facilitate acoustic transmission, agarose solution is poured around 3D mold connected with holes of the acrylic box. By applying speckle image velocimetry(SIV) technique, flow information in the bifurcated channel was estimated. Considering that ultrasound signal amplitude is determined by red blood cell (RBC) aggregation, RBC aggregation in the bifurcated channel can be estimated through the analysis of ultrasound signal. As examples of microfluidic device which mimic the CVD model, velocity fields in microfluidic devices with stenosis and aneurysm were introduced.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.70-70
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• 2003

Active sites and substrate bindings of 1-aminoxyclopropane-1-carboxylate oxidase (MD-ACO1) catalyzing the oxidative conversion of ACC to ethylene have been determined based on site-directed mutagenesis and comparative modeling methods. Molecular modeling based on the crystal structure of Isopenicillin N synthase (IPNS) provided MD-ACO1 structure. MD-ACO1 protein folds into a compact jelly roll shape, consisting of 9 ${\alpha}$-helices, 10 ${\beta}$-strands and several long loops. The MD-ACO1/ACC/Fe(II)/Ascorbate complex conformation was determined from automated docking program, AUTODOCK. The MD-ACO1/Fell complex model was consistent with well known binding motif information (HIS177-ASP179-HIS234). The cosubstrate, ascorbate is placed between iron binding pocket and Arg244 of MD-ACO1 enzyme, supporting the critical role of Arg244 for generating reaction product. These findings are strongly supported by previous biochemical data as well as site-directed mutagenesis data. The structure of enzyme/substrate suggests the structural mechanism for the biochemical role as well as substrate specificity of MD-ACO1 enzyme.

• 환경생물
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• 제26권1호
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• pp.1-7
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• 2008

A mathematical model for the synergistic interaction of physical and chemical environmental agents was suggested for quantitative prediction of irreversibly damaged cells after combined exposures. The model took into account the synergistic interaction of agents and was based on the supposition that additional effective damages responsible for the synergy are irreversible and originated from an interaction of ineffective sublesions. The experimental results regarding the irreversible component of radiation damage of diploid yeast cells simultaneous exposed to heat with ionizing radiation ($^{60}Co$) or UV light (254 nm) are presented. It was shown that the cell ability of the liquid holding recovery decreased with an increase in the temperature, at which the exposure was occurred. A good correspondence between experimental results and model prediction was demonstrated. The importance of the results obtained for the interpretation of the mechanism of synergistic interaction of various environmental factors is discussed.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.207-209
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• 2003

Quantifying crop production is one of the most important applications of remote sensing in which the temporal and up-to-date data can play very important role in avoiding any immediate insufficiency in agricultural production. A combination of climatic data and biophysical parameters derived from Landsat7 ETM+ was used to develop a mathematical model for wheat yield forecast in different geographically wide Wheat growing districts in Egypt. Leaf Area Index (LAI) and fraction of Absorbed Photosynthetically Active Radiation (fAPAR) with temperature were used in the modeling. The model includes three sub-models representing the correlation between the reported yield and each individual variable. Simulation results using district statistics showed high accuracy of the derived correlations to estimate wheat production with a percentage standard error (%S.E.) of 1.5% in El- Qualyobia district and average (%S.E.) of 7% for the whole wheat areas.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.34-34
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• 2003

Protein unfolding is a key step in several cellular processes, including protein translocation across some membranes and protein degradation by ATP-dependent proteases. C1pAP protease and the proteasome can actively unfold proteins in a process that hydrolyzes ATP, These proteases catalyze unfolding by processively unraveling their substrates from the attachment point of the degradation signal. As a consequence, the ability of a protein to be degraded depends on its structure as well as its stability. An ${\alpha}$-helix is easier to unravel than a ${\beta}$-strand. In multidomain proteins, independently stable domains are unfolded sequentially. The steric constraints imposed on substrate proteins during their degradation by the proteasome were investigated by constructing a model protein in which specific parts of the polypeptide chain were covalently connected through disulfide bridges. The cross-linked model proteins were fully degraded by the proteasome, but two or more cross-links retarded the degradation slightly. Our results suggest that the pore of the proteasome allows the concurrent passage of at least three stretches of a polypeptide chain, and also explain the limited degradation by the proteasome that occurs in the processing of the transcription factor NF-KB, and also implicate difficulty in degradation of amyloidal aggregates by the proteasome

• 대한원격탐사학회지
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• 제22권6호
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• pp.533-542
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• 2006

Lidar는 정확도 높은 고밀도의 점 자료를 제공함으로써 지형공간에 대한 3차원 정보를 제공한다. 특히, 산림과 같은 식생 지역에서는 레이저 신호가 투과되어 지면에서 반사되는 자료가 기록되므로 산림이 밀집하여 존재하는 공간에 대한 수치고도모델 제작에 용이하다. 이 연구에서는 우리 나라 중부지역의 산림에서 획득한 Lidar자료의 수직적 분포 특성을 살펴보고자 하며, 산림자원정보를 추출 및 수치고도자료(DEM)를 획득하기 위한 필수 과정인 지면점들을 분리하는 방법을 제안하고자 한다. Lidar 자료의 수직적인 분포는 산림을 구성하는 수종, 밀도 및 수관의 형태 등에 따라 영향을 많이 받으며, 이러한 산림에서 나타나는 Lidar 자료의 특성을 이용하여 제안된 지면점 분리 방법은 초기 수신신호(First return: FR) 및 말기 수신신호(Last Return: LR)를 함께 이용함으로써 일반적으로 지면점을 분리하는데 요구되는 임계치를 고려하지 않아도 된다는 효율성을 가진다. 제시된 방법으로 분리된 지면점을 이용하여 수치고도모델을 제작하였으며, 이를 기반으로 산림의 중요한 정보가 되는 수고, 수관울폐도 등의 임목의 생물리학적 인자를 보다 정확하게 추출할 수 있다.

• 한국방사선학회논문지
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• 제9권6호
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• pp.417-420
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• 2015

본 연구는 탄소 빔의 분할조사 후 세포생존율 (Surviving Fraction, SF) 값에 따른 Linear-Quadratic model, Incomplete Repair model, Marchese model의 결과값을 비교하기 위해 진행하였다. 탄소 빔을 4fraction까지 조사한 후 얻은 세포생존율 값을 바탕으로 mathematica 프로그램 (ver 9.0)을 이용하여 각각의 모델로 결과값을 얻어 비교해 보았다. 그 결과 즉시 NB1RGB를 시딩한 값은 repair가 감안되지 않은 LQ 모델이 적합하였지만 fraction 시행한 후의 결과값은 오차를 보였다. 따라서 Potentially Lethal Damage Repair (PLDR)과 Sublethal Damage Repair (SLDR)의 발생을 각각 감안한 repair 모델을 이용하여 적합한지 판단하였다. 이를 바탕으로 탄소 빔의 분할 조사 시 LQ 모델에 각각의 repair의 양을 감안한 새로운 회복 관련 모델의 적용 가능성을 보고자 하였다.

• Bulletin of the Korean Chemical Society
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• 제30권6호
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• pp.1262-1266
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• 2009

Thermodynamics of the interaction between Cerium (III) chloride, $Ce^{3+}$, with Human Serum Albumin, HSA, was investigated at pH 7.0 and $27\;{^{\circ}C}$ in phosphate buffer by isothermal titration calorimetry. Our recently solvation model was used to reproduce the enthalpies of HSA interaction by $Ce^{3+}$. The solvation parameters recovered from our new model, attributed to the structural change of HSA and its biological activity. The interaction of HSA with $Ce^{3+}$ showed a set of two binding sites with negative cooperativity. $Ce^{3+}$ interacts with multiple sites on HSA affecting its biochemical and biophysical properties.