• Applied Biological Chemistry
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• v.25 no.4
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• pp.218-223
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• 1982

Physicochemical properties and aging of chestnut, Castanea cretana(Eungi), starch were investigated. The starch granules were irregular oval shape with the ratio of short and long axis of 1 : 1.4 and the size of $2.9-21.4{\mu}$ (average $10\;{\mu})$). The starch showed a typical B-type X-type diffraction pattern. Amylose content and water binding capacity were 22.7% and 81.5%, respectively. The optical transmittance of 0.1% starch suspension increased rapidly from $55^{\circ}C$. The swelling power of the starch repidly increased betwen $55^{\circ}C$ and $60^{\circ}C$, and its increase slowed down thereafter. Amylograms of starch at 5% and 6% concentrations indicated that the starch was stable against heat and shear force. The viscosity at 6% concentration was over twice higher than that at lower concentration. The time constant(reciprocal of rate constant) for 45% starch gel stored at $21^{\circ}C$ was 1.68 days.

• Applied Biological Chemistry
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• v.30 no.3
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• pp.219-226
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• 1987

Peroxidase isozyme C was isolated from mung bean cotyledon and purified to homogeneity as ascertained by chromatography and polyacrylamide gel electrophoresis, and then crystallized. Purification procedures included ammonium sulfate precipitation and column chromatography on Sephadex G-75, DEAE-cellulose and DEAE-Sephadex A-50. Peroxidase isozyme C was purified about 63 fold with 5% recovery. Isozyme C showed optimal activity at pH 5.0 with o-dianisidine and at pH 6.0 with guaiacol as substrate, and the optimal temperature was $70^{\circ}C$. Molecular weight of 50,000 was estimated for the isozyme C by SDS-polyacrylamide gel electrophoresis. At $70^{\circ}C$, it took 30 min to inactivate the isozyme to 50%, and at $80^{\circ}C$, this isozyme was almost completely inactivated in 20 min. The Km value of isozyme C for o-dianisidine was 0.11mM and that for guaiacol was 60.98mM using hydrogen peroxide as cosubstrate, and the kinetic pattern showed a competitive cyanide inhibition with respect to substrate. The crystalline structure of isozyme C was rectangular in shape.

• Archives of design research
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• v.19 no.5 s.67
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• pp.255-268
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• 2006

This study raised a question about 'how user's psychological value consciousness influences design evaluation and evaluated 14 product samples. Three main categories were chosen to be analyzed; product evaluation by step, value consciousness toward products, and creation of shape image and design evaluation. In order to obtain results, four research hypotheses were established a and case study was conducted as part of 'conclusive research' for verification. 120 university students in their 20s majoring in product design were chosen as testees in a bid to increase the accuracy of data. With data collected, the whole flow was analyzed by simple tabulation and further analysis was carried out in three evaluation items. An analysis method was mainly quantitative, focusing on multivariate analysis like factor analysis, cluster analysis, etc. The empirical analysis of this study was verified at P<.05 significance level and SPSSWIN 12.0 program was used for statistic process. As a result, four conclusions were gained regarding 'user's value consciousness toward products and pattern of design evaluation'.

• Journal of Pharmaceutical Investigation
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• v.23 no.3
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• pp.9-18
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• 1993

Sugar spheres loaded with melatonin (MT) were coated with $Aquacoat^{\circledR}$ to control the release rate of MT over 8 hours. A zero-order release pattern over 8 hours was obtained with 20% coating on 8-10 mesh beads in USP basket dissolution studies. MT in 20% coated beads was quite stable at room temperature with less than 5% MT degraded during 6 months' storage. Dissolution profiles were also unchanged after 6 months. An oral preparation containing MT-loaded uncoated beads for immediate release and 20% coated beads with $Aquacoat^{\circledR}$ for controlled release over 8 hours was evaluated in six human subjects. When total 0.5 mg MT as low dose (immediate release portion of MT, 0.1 mg) was administered to four subjects, average peak plasma MT concentration was reached at about 600 pg/ml and maintained at about 10 pg/ml over 8 hours. Plasma MT concentration-time profiles were similar in shape to computer-simulated profiles. However, maximal plasma MT concentrations were three times greater compared to computer simulated curve. These results suggest that MT dose, ratio of immediate and controlled release MT, and pharmacokinetic parameters selected are adjusted to mimic endogenous MT concentration-time curve. In another study, 0.2 mg MT having 10% of immediate release portion and 80% controlled release portion produced plasma MT concentration-time curve which is more similar to endogenous profiles. A low bioavailability (<20%) may result from extensive first pass metabolism and remaining amounts of MT from controlled beads. A good correlation between plasma MT concentration and urinary excretion rate of 6-sulphatoxymelatonin (6-STMT), a major metabolite of MT was observed. As plasma MT concentration increased, urinary excretion rate of 6-STMT increased concomitantly. The linear relation between plasma MT and urinary excretion rate of 6-STMT was statistically significant. This result suggests that urinary 6-STMT may be used as an index of circadian rhythms of MT in humans.

• Journal of Pharmaceutical Investigation
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• v.15 no.2
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• pp.53-62
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• 1985

Pivampicillin hydrochloride is a kind of broad spectrum antibiotics with bactericidal action, and is used in many countries, although it has bitter taste, unpleasant odour and side effects of irritating gastric mucosa, nausea, penicillin allergy, etc. For the improvement of such side effects of pivampicillin hydrochloride, microcapsules, with wall of ethylcellulose, have been prepared by coacervation method. The shape was observed through the scanning electron microscope, the release of the drug into an aqueous medium was studied and the effects of core: ethylcellulose ratio were interpreted as well as making sensory evaluation of taste and odour. There was decreasing trend in dissolution rate of the drug with the increase of core: ethylcellulose ratios, and the smaller microcapsules released their contents more rapidly. A linear relationship was established between the amount of ethylcellulose and the time for 60% release of the drug, and the release pattern was found to have similar characteristics to the release of the drug from an insoluble porous matrix. The release of the drug in the artificial intestinal fluids (pH 6.8) was found to be similar to that in water, while the release in the artificial gastric juice (pH 1.2) was slightly slower. Bioavailability of microcapsule was compared with that of pivampicillin hydrochloride in rabbits using serum concentration and urinary excretion measurements. Microcapsule gave showed slightly higher serum level than pivampicillin hydrochloride from 2 hours after administration, while no significant difference was observed in the accumulated urinary excretion rate between pivampicillin hydrochloride and microcapsule. The ulcer index of pivampicillin hydrochloride administered group was 2.6, and microcapsule administered group was 1.5, while control group was 0.8. Therefore it may be concluded that microencapsulation of pivampicillin hydrochloride is a useful pharmaceutical approach to protect the gastrointestinal tract from being injured by direct contact of pivampicillin hydrochloride without any significant difference of bioavailability.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.71-74
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• 1994

In cementless total hip arthroplasty(THA), an initial stability of the femoral component is mandatory to achieve bony ingrowth and secondary long term fixation. Bone ingrowth depends strongly on relative micromotion and stress distributions at the interface. Primary stability of the femoral component can be obtained by minimizing the magnitude of relative micromotions at bone-prosthesis interface, Hence an accurate evaluation of interface behavior and stress/strain fields in the bone implant system may be relevant for better understanding of clinical situations and improving THA design. However, complete evaluation of load transfer in the bone remains difficult to assess experimentally, Hence, recently finite element method (FEM) was introduced in orthopaedic research field to fill the gap due to its unique capacity to evaluate stress in structure of complex shape, loading and material behavior. The authors developed the 3-dimensional numerical finite element model which is composed of totally 1179 elements off and 8 node blick. We also analyzed the micromotions at the bone-stem interface and mechanical behavior of existing bone prosthesis for a loading condition simulating the single leg stance. The result indicates that the values of relative motion for this well fit Multilock stem were $150{\mu}m$ in maximum, $82{\mu}m$ in minimum, and the largest relative motion developed in medial region of proximal femur with anterior-posterior direction. The proximal region of the bone was much larger in motion than the distal region and the stress pattern shows high stress concentration on the cortex near the tip of the stem. These findings indicates that the loading in the proximal femoral bone in the early postoperative situation can produce micromotions on the interface and clinically cementless TEA patient should not be allowed weight bearing strictly early in the postoperative period.

• Journal of Conservation Science
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• v.30 no.4
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• pp.365-372
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• 2014

The purpose of the present study is to determine the species of red and green pigments used on paintings of Korean temples and also to compare the two pigments according to the particle characteristics. The component analysis shows that the red pigment consists of cinnabar, hematite, and minium and the green pigment are composed of atacamite, celadonite, and malachite. The result suggests that mixture of various pigments were applied to the painting. When it comes to the particle characteristics, there are various hedral or anhedral shapes such as sharp, long, angular, and platy shapes even in the same cinnabar. In addition, the green pigment also shows a similar pattern with those of the red pigment. Up to now, an identification of minerals has been relied on examination of component and crystal shape. However, it is notable that using form related characteristics can be a better and useful method not only for categorization of pigments which are similar in terms of color and species but also specific index.

• Journal of Biomedical Engineering Research
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• v.28 no.5
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• pp.601-608
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• 2007

2 Dimensional Gel Electrophoresis(2DGE) is an essentialmethodology for analysis on the expression of various proteins. For example, information for the location, mass, expression, size and shape of the proteins obtained by 2DGE can be used for diagnosis, prognosis and biological progress by comparison of patients with the normal persons. Protein spot matching for this purpose is comparative analysis of protein expression pattern for the 2DGE images generated under different conditions. However, visual analysis of protein spots which are more than several hundreds included in a 2DGE image requires long time and heavy effort. Furthermore, geometrical distortion makes the spot matching for the same protein harder. In this paper, an iterative algorithm is introduced for more efficient spot matching. Proposed method is first performing global matching step, which reduces the geometrical difference between the landmarks and the spot to be matched. Thus, movement for a spot is defined by a weighted sum of the movement of the landmark spots. Weight for the summation is defined by the inverse of the distance from the spots to the landmarks. This movement is iteratively performed until the total sum of the difference between the corresponding landmarks is larger than a pre-selected value. Due to local distortion generally occurred in 2DGE images, there are many regions in whichmany spot pairs are miss-matched. In the second stage, the same spot matching algorithm is applied to such local regions with the additional landmarks for those regions. In other words, the same method is applied with the expanded landmark set to which additional landmarks are added. Our proposed algorithm for spot matching empirically proved reliable analysis of protein separation image by producing higher accuracy.

• Journal of Biomedical Engineering Research
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• v.33 no.4
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• pp.169-176
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• 2012

Tumor cell morphology is closely related to its migratory behaviors. An active tumor cell has a highly irregular shape, whereas a spherical cell is inactive. Thus, quantitative analysis of cell features is crucial to determine tumor malignancy or to test the efficacy of anticancer treatment. We use 3D time-lapse phase-contrast microscopy to analyze single cell morphology because it enables to observe long-term activity of living cells without photobleaching and phototoxicity, which is common in other fluorescence-labeled microscopy. Despite this advantage, there are image-level drawbacks to phase-contrast microscopy, such as local light effect and contrast interference ring. Therefore, we first corrected for non-uniform illumination artifacts and then we use intensity distribution information to detect cell boundary. In phase contrast microscopy image, cell is normally appeared as dark region surrounded by bright halo ring. Due to halo artifact is minimal around the cell body and has non-symmetric diffusion pattern, we calculate cross sectional plane which intersects center of each cell and orthogonal to first principal axis. Then, we extract dark cell region by analyzing intensity profile curve considering local bright peak as halo area. Finally, we calculated the Fourier descriptor that morphological characteristics of cell to classify tumor cells into active and inactive groups. We validated classification accuracy by comparing our findings with manually obtained results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3611-3616
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• 2013

Physical characteristics of a magneto-rheological(MR) fluid can be influenced by a magnetic field. In the present study, the behaviors of MR fluid are visualized and the shear stresses are measured under the magnetic field for density 1.3, 1.5 and 1.7 $g/cm^3$, and viscosity 100, 1000 and 10000cp. When the magnetic field is applied, particles of MR fluid are arranged along lines of magnetic field. It is observed that the flow pattern of MR fluid under the magnetic field is different from that of MR fluid without the magnetic field. Shear stress of MR fluids under the magnetic field changes significantly. Shear stress by the magnetic field increases the shape of a quadratic equation. When the density changes from $1300kg/m^3$ to $1700kg/m^3$ at 2.0A, the shear stress increases about 33%.