• Korean Journal of Materials Research
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• v.5 no.2
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• pp.251-258
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• 1995

In an effort to increase the thermoelectric figure of merit by reducing the thermal conductivity, the unidirectionally solidified n-type (Bi, Pb)-Te based alloys which form a $Bi_{2}Te_{3}-PbBi_{4}Te_{7}$eutectic lamellar structure were investigated with the microstructural control at various solidification conditions. PbBi_{4}Te_{7}$ lamellae were grown on cleavage plane(0001) of $Bi_{2}Te_{3}$ and the interlamellar spacing decreased from 10.4 $\mu \textrm{m}$to 3.2$\mu \textrm{m}$ with growth velocity variation from 1.4 \times 10^{-4}$cm/sec to $8.3 \times 10^{-4}$cm/sec. Seebeck coefficient was constant, $\mid$$\alpha$$\mid$=29 $\mu$ V/K regardless of growth direction, growth velocity and temperature gradient. Electrical conductivity showed a tendency to decrease slightly with growth velocity and it parallel to growth direction was about three times as large as perpendicular direction. The figures of merit were varied differently from Seebeck coefficients and electrical conductivities depending on the growth direction, growth velocity and temperature gradients. They showed the relative increase in case of perpendicular direction compared with parallel to growth direction. It is believed to be due to the reduction of the thermal conductivity according to decrease of the interlamellar spacing.

• Journal of Chest Surgery
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• v.38 no.11 s.256
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• pp.746-760
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• 2005

Background: Following the implantation of heart valve prostheses, it is important to maintain therapeutic INR to reduce the risk of thromboembolism. The objectives of this study were to determine the causes of nontherapeutic INRs, and to identify the factors associated with nonadherences to warfarin therapy in Korean outpatients with prosthetic heart valves managed by a pharmacist-run anticoagulation service (ACS). Material and Method: A retrospective chart review was completed for all patients enrolled in the ACS at Seoul National University Hospital from March, 1997b to September, 2000. The data on 868 patients (5,304 visits) who were at least 6 months post-valve replacement were included. All possible causes of nontherapeutic INRs were documented for each patient visit. The association of covariates to noncompliance was investigated by univariate analysis. Result: The reasons for nontherapeutic INRs were identified as follows: inadequate dosage adjustment $(21\%)$, nonadherences to dosing regimen $(13\%)$, drug/herbal interactions $(12\%)$, changes in diet $(7\%)$, and indeterminate cause $(42\%)$. Younger age, shorter duration of ACS and longer duration of warfarin therapy were associated with nonadherence. Conclusion: In this study, nonadherence and interactions between diet and medications were found to be important factors influencing nontherapeutic INRs. Longer duration of enrollment in the ACS affected the adherence to warfarin therapy Positively whereas younger age and longer duration of warfarin therapy affected negatively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.681-688
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• 1996

To investigate the effort of drying methods on the physicochemical properties of agar, gel strength, viscosity, melting and setting point, and phase transition by differential scanning calorimetery (DSC) during its heating were determined. In addition the structural differences of agar powder by scanning electron microscope (SEM) was examined. The most shortest onset temperature of gel strength increase was extruding method among any other methods. Viscosity of agar with hot air method, 400.00 cps at $45^{\circ}C$, was markedly increased, but with spraying and extruding ones were little change. The melting and setting point, and the temperature for maximum endothermic and enthalpy for agar with extruding one, $80.01^{\circ}C,\;36.05^{\circ}C\;and\;61.72^{\circ}C,\;0.73\;cal/g$, respectively, were lowest among the drying ones. But in the case of reheating after gelling, there were little change in all methods. Observing the surface structure of agar with SEM, extruding method showed the most unstable with absorptive property.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.520-523
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• 2000

Anti-ulcer effects of depolymerized alginate (HAG-10, average molecular weight 10,000; HAG-50, average molecular weight 50,000; HAG-100, average molecular weight 100,000) obtained by hydrolysis of alginate by heating at $121^{\circ}C$, against $HCl{\cdot}ethanol$ and water-immersion stress in rats were investigated. The acute gastritis, induced by $HCl{\cdot}ethanol$, and the gastric ulcer, induced by water-immersion stress, were inhibited dose-dependently by administration of HAG-50, HAG-100 and alginate. Histopathological lesions of the gastritis and gastric ulcer in rats treated with HAG-50, HAG-100 and alginate were significantly lower than those in rats fed with HAG-10. The inhibition rates (${\%}$) on acute gastritis induced by $HCl{\cdot}ethanol$ and gastritis ulcer induced by water-immersion stress in rats, were $13.00{\%}\;and\;15.74{\%}$of HAG-10, $41.15{\%}\;and\;35.72{\%}$ of HAG-50, $41.58{\%}\;and\;35.37{\%}$ of HAG-100, and $45.17{\%}\;and\;41.11{\%}$ of alginate, respectively. These results suggested that HAG-50, HAG-100 and slginate had a protective effect against the gastritis and gastric ulcer. The effect was not as visible when using HAG-10 in rats. From the present results, it was suggested that HAG-50 was an effective anti-ulcer agent against $HCl{\cdot}ethanol$and water-immersion stress in rats.

• Microbiology and Biotechnology Letters
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• v.9 no.3
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• pp.159-164
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• 1981

Reinforced Calcium-alginate gel entrappment method for enzyme immobilization is described with an example of penicillin amidase from Bacillus megaterium KFCC 10029, a partially constitutive mutant of B. megaterium ATCC 14945. Penicillin amidase recovered from the fermentation broth by adsorption on celite is mixed with alginate and gelatin solution, and cast into a pellet or noodle form by coagulation in calcium salt solution followed by crosslinking with glutaraldehyde. Optimum pH and temperature of the immobilized enzyme preparation were 8.0 and 6$0^{\circ}C$, respectively. Kinetic constants such as Km value and the inhibition constant of 6-APA and phenylacetic acid were 2.6 mM, 7.4 mM and 21.2 mM, respectively. The enzyme leakage from the adsorbent during operation was successfully prevented owing to the increase of physical strength of gel coat. The half lives in a column reactor were 6 and 30 days at the respective temperature of 4$0^{\circ}C$ and 3$0^{\circ}C$, which were the 6-8 fold increased values as compared with those of without entrappment. The results highly recommended the use of reinforced Calcium-alginate gel entrappment method for the enhancement of physical strength and the operational stability of alginate gel entrapped enzyme.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.158-162
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• 1999

A beverage was manufactured with onion extract for which onions were boiled with water and filtered. The concentration of cyclodextrin was studied to improve its quality in manufacturing the onion beverage and its antioxidative and antifatigue effect was investigated in vitro or in vivo. One percent of cyclodextrin was optimum concentration to prevent precipitation and to remove pungent taste and keep mild taste during storage at room temperature and 40$^{\circ}C$. Water extract of onion, used to manufacture onion beverage shown significant difference in antioxidative effect based on peroxide value and thiocyanate method. For the study of antifatigue, swimming performance of mice which fed with onion beverage and water extracts of onion and garlic for 2 weeks was investigated. The mice fed with onion beverage swam longer than those fed with water extract of onion and garlic.

• Journal of Life Science
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• v.20 no.6
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• pp.922-928
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• 2010

This study was carried out to develop safe and novel anticoagulation agents from oriental medicinal herbs. From 33 medicinal herbs, 40 different ethanol extracts were prepared according to place of origin or extraction parts, and anticoagulation activities were evaluated by determination of thrombin time (TT), prothrombin time (PT) and activated partial thromboplastin time (aPTT). The average water content and average extraction ratio for the medicinal herbs were $6.85{\pm}2.26%$ and $5.27{\pm}4.25%$, respectively. Evaluation of TT at various concentrations of the extract led to the selection of Mucuna birdwoodiana, Prunus armeniaca, Cacalia ainsliaeiflora, Cinnamonum aromaticum, and Rhus javanica Linneas potent antithrombosis medicinal herbs. Evaluation of PT and aPTT showed that the extracts of R.javanica Linne, M. birdwoodiana, and P. armeniaca have strong anticoagulation activities. Determination of hemolytic activities of 40 different ethanol extracts against human red blood cells, however, showed that only M. birdwoodiana, C. ainsliaeiflora, C. aromaticum, and R. javanica Linnehas strong anticoagulation activity without hemolytic activity at a concentration of 500 mg/ml. Our results suggest that oriental medicinal herbs, which are under a mass-production system, have potentialas a safe and novel source of anticoagulants, as well being a thrombin-specific and coagulation factor-specific inhibitor.

• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.172-177
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• 1971

The amount of the milk clotting enzyme which is produced by Dothiorella ribis in wheat bran was 950 Soxhlet units per gram of wheat bran. The milk clotting activity of this enzyme was increased by the elevation of clotting temperature and by the increase of the addition of $CaCl_2$ to milk. It was also increased when the pH of milk was lower than that of the fresh milk. When milk was diluted by distilled water, the milk clotting activity of the enzyme was decreased. And its milk clotting activity was good when milk was pasteurized at low temperature. The enzyme of Dothiorella ribis has larger proteolytic activity per Soxhlet unit than that of the milk clotting enzyme of Mucor pusillus Lindt. This enzyme was rather stable between pH 6 and pH 8 when it was conditioned for ten minutes. The heat stability of enzyme was tested by treating it under the condition for $10{\sim}60$ minutes. And the enzyme was stable under the temperature of $45^{\circ}C$. Also the recovery of protein as a form of curd was 76.2 percent to the total protein content of milk.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.2
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• pp.37-55
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• 1997

최근 선진국가들에서는 전자파 장애 증후군에 관심이 집중되고 있는데, 전자파에 장기 노출 되는 인구에서 뇌암이나 유방암, 백혈병 등의 발생률이 높다는 보고(Kolmodin-Hedman 등, 1988 ; Demers등, 1991)가 있어서 전자제품의 생산업체는 물론이고 사용자에 대해서도 불안한 관심사가 되 어 있다. 전자파가 생체에 미치는 영향은 열적 효과와 비열적 효과에 의한 것으로 구분된다. Microwave는 약 300MHz에서 300GHz 사이(파장 1m에서 1mm사이)의 주파수를 가지는 전자파로서 이온의 운동이나 쌍극자분자(dipole molecule)들을 진동시키므로서 조직에 열이 발생한다. 열이 과도하게 발생하면 세포 단백질이 응고하게 되는 등 일반적으로 생각할 수 있는 고열로 인한 여러 가지 유해환경이 조직 에 조성될 수 있다. 실제로 고전압의 전자파에 노출된 안구의 수정체에 백내장 등의 병변이 발생한 것 으로 보고된 바 있다(Adey,1981). 일반적으로 전자파의 생체에 대한 작용으로는 이렇듯 조직에 흡수 되는 전자파의 에너지에 의한 열작용이 지배적인 것으로 생각되어 왔다. 그러나 초저주파역대(Extre- mely low frequency, EMF)의 변조 및 펄스파 등의 영향에 관해서도 조직의 온도상승으로는 설명할 수 없는 현상이 보고된 바 있다. 이러한 비열적 효과가 신경계에 끼치는 영향에 대해서는 혈액뇌관문 의 투과성 변화(Oscar와 Hawkins, 1977), 뇌종양 발생, 칼슘대사 이상 및 신경전달물질에 대한 영향 등이 주장(Anderson, 1993)되고 있으나 아직 그 분명한 기전이 밝혀져 있지 않은 상태이다. 또한 그 영향의 평가에 서도 일정한 기준이나 지표가 정해지지 않은 실정이다. 그러므로 신경계에 대한 대체적인 소개와 더불어 전자기파의 영향에 대한 이제까지의 보고를 종합 하고 향후 연구의 방향을 소개하고자 한다.> 이온이 공동 첨가제로 더 적합하다.u(30 .angs. )/CoFe(35 .angs. )/NiO(800 .angs. ) 구조를 갖는 spin-valve 박막은 극대 MR비 6.3%, 유효자기장감응도 약 0.5(%/Oe)를 보여 spin-valve head 재료로 적합함을 알 수 있었다.다.다.다.는 각각 148 meV .angs. $^{2}$, 103.8 meV .angs. $^{2}$와 1.77 * $10^{-6}$ erg/cm, 0.67 * $10^{-6}$ erg/cm 였다.다.자 노인들을 영주권자와 귀화 시민권자의 구분없이 하나의 집단으로 간주하고 분석해 왔던 것을 볼 때, 앞으로의 연구는 이론적으로나 방법론적으로 시민권의 유무가 주거형태에 끼치는 영향도 함께 고려해야 할 것이다.에 나타난 인도의 영향은 여성복식과 남성복식에 있어서 서로 유사점과 차이점이 보이는데, 인도의 영향이 여성복식에 있어서 그 빈도가 더 높고, 종류가 더 다양함을 볼 수 있다. 여성복식에 있어서는 12가지의 다양한 인도복식스타일이 나타났으며, 그중 가장 많이 보이는 스타일은 Indian Shirt/Blouse/Smock/ Dress이며, 그 뒤를 이어 Madras, Indian lowery등을 볼 수 있다. 남성복식애 나타난 7가지의 스타일 중에는 Madras가 가장 빈도가 높으며 그외의 스타일들은 그 빈도가 매우 낮음을 볼 수 있다. 인도의 영향의 정도 (Attribution Categories) 있어서는 여성과 남성복식 모두에 있어서 인도에서 직접 수입된(originated) item이 각각 전체의 90%와 81%를 차지하여, 인도복식의 영향은 받았으나 미국내에서 제작된(attributed and connotated) item 보다 휠씬 더 많은 수를 보였다. 인도복식스타일이 가장

• Journal of Life Science
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• v.25 no.7
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• pp.757-764
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• 2015

The immature fruit of Rubus coreanus Miquel (bokbunja in Korean) is mainly consumed as a fruit wine due to its sour taste and low sugar content. The lees (LBW) remaining after the production of bokbunja wine are discarded as they have no specific usage. The aim of this study was to develop high-value-added biomaterials for functional foods and beauty/health products by investigating the anti-microbial, anti-oxidant, and anti-thrombosis activities of LBW using ethanol and hot water extracts and their subsequent organic solvent fractions. The ethyl acetate (EA) fraction of LBW extracts has a high polyphenol content (413–459 mg/g), and showed strong anti-microbial activity against gram-positive bacteria. The EA fraction also showed excellent radical-scavenging activity against DPPH anion, ABTS cation, and nitrite, with strong reducing power. The polyphenol-enriched EA fraction strongly inhibited thrombin, prothrombin, and blood coagulation factors. The butanol fraction showed a specific inhibition of coagulation factors, as measured in activated partial thromboplastin time assay, which is linked to intrinsic blood coagulation. The butanol fraction also showed strong inhibition of platelet aggregation, at levels comparable to aspirin. The residue of the hot-water extract, which is produced by sequential solvent fractionation of the LBW extract, showed superior inhibition against platelet aggregation when compared to aspirin. Our results suggest that the LBW, which are currently discarded, are a promising source of novel functional foods and beauty/health products.