• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.29-33
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• 1990

The study was attempted to scrutinize the normal osmotic fragility of erythrocyte in the domestic ruminants, making a comparison with that of human and canine. The animals used in the experiment were apparently healthy adult Holstein cattle, Korean native cattle, sheep (Corriedale) and Korean native goats. Osmotic fragility of erythrocytes was the highest in the Korean native goats, and the next were sheep and Korean native cattle, and Holstein cattle in order. In other words, erythrocytic resistance to osmotic lysis was the strongest in Holstein cattle and the most weak in Korean native goats among the domestic ruminants. In general, resistance of erythrocytes was stronger in human and canine than in the domestic ruminants.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.27-30
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• 2005

In a microfluidic chips pressure driven flow or electro-osmotic flow has been usually employed to deliver bio-samples. Flow in the chips is usually slow and the mixing performance is poor. A micro-mixer with a rapid mixing is important for practical applications. In this study a newly designed and electro-osmotic driven micro-mixer is proposed. This design is comprised of a channel and a series of metal electrodes periodically attached on the side surface. In this configuration electro-osmotic flows and the stirring effects are simulated three-dimensionally using a commercial code, CFD-ACE. Focus is given the effect on the electro-osmotic flow characteristics under the local variation of the electric field.

• Korean Journal of Veterinary Service
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• v.15 no.2
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• pp.144-149
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• 1992

The study was attempted to scrutinize the normal osmotic fragility of erythrocytes in domestic poultry such as chicken, quail and duck making a comparison with that in domestic mammalia such as dog and pig. Osmotic fragility of erythrocytes was determined on blood samples from 10 healthy adult animal in each species. Optical initial hemolysis of erytyrocytes occurred at $0.395{\pm}0.03%$ Nacl for chicken, $0.410{\pm}0.03%$ for duck, $0.440{\pm}0.02%$ for quail, $0.470{\pm}0.05%$ for dog and $0.560{\pm}0.03%$ for pig. Optical complete hemolysis of erytyrocytes occurred at $0.270{\pm}0.02%$ Nacl for chicken, $305{\pm0}.03%$ for duck, $0.360{\pm}0.02%$ for quail, $0.370{\pm}0.03%$ for dog and $0.455{\pm}0.03%$ for p. In other words, erythrocytes of poultry have stronger resistance to osmotic Iysis than that of mammalia, showing the strongest resistance In chicken among the tested poultry.

• Korean Journal of Microbiology
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• v.29 no.4
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• pp.215-220
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• 1991

MudJ(Km.lac) operon fusions were used in the identification of osmotic-inducible genetic(osi) loci in Salmonella typhimurium. Expression of osi::lacZ(osi5001, 5027) genes were dramatically induced 39-189 fold when the osmolarity was increased. Seven osm::lacZ genes were constituvely expressed under both low and high osmotic strength. The osi5001::lacZ fusion strains showed the enhanced osmotolerance and the reduced expression of the osi5001::lacZ in the presence of 1mM proline or betaine as osmoprotectants. Four osmotic inducible genetic loci were mapped into 36 (YK531), 44 (YK504), 57 (YK501) and 84 (YK528) map unit by testing the cotransduction frequency.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.51-52
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• 2002

Electro-osmotic flow in a PDMS microchannel of $66{\mu}m\;\times\;200{\mu}m\;\times\;3cm$ has been investigated using a micro PIV system. The field of view was $1056{\mu}m\;\times\;200{\mu}m$ and instantaneous velocity fields were obtained using two-frame cross-correlation method with $64\;\times\;64\;pixels^2$ interrogation window. In this study, we focused on the effect of applied electric field on the variation of internal flow with varying the electric field and seeding particles. The electro-osmotic flow shows a flat velocity profile and the mean velocity is proportional to the applied electric field.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.121-126
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• 1990

Internal mass transfer during osmotic concentration of apples in sugar solutions was exami-ned as a function of concentration temperature and immersion time of those solutions using moisture loss sugar gain molality and rate parameter. Influence of osmotic concentration processes on browning reaction was also evaluated compared to control In creasin the concen-tration and temperature of sugar solutions increased moistrue loss sugar gain molality and rate parameter. Water loss was rapid early in the process and then levelled off, The same phenomena were occurred on sugar gain only in higher concentration(60$^{\circ}$ brix). IN lower concentration (30$^{\circ}$brix) sugar gain was gradually increased during whole process. Moisture loss during osmotic concentration using a sugar solution(60$^{\circ}$ brix 6$0^{\circ}C$) with 180min immer-sion time was 45.79% Effect of osmotic concentration befor air dried to 4% M.C(wet basis) on browning reaction was significant. Minimum browning reaction during air drying was carried out using a pretreatment such as osmotic concentration in sugar solution(60$^{\circ}$brix 45$^{\circ}C$) with 150min immersion time(O.D=0.01) compared to control(O.D=0.17)

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.866-871
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• 1997

This study was carried out to determine the effect of osmotic dehydration as pretreatment on the qualities of dried cherry-tomatoes. The weight reduction and solid gain in osmosed cherry-tomato were increased by increasing sugar concentration, immersion temperature and time; among three parameters, the immersion temperature affected more than sugar concentration and immersion time did. The moisture content was decreased as increasing sugar concentration, immersion temperature and time, and it was the lowest at the osmotic conditions of 7$0^{\circ}C$, 60$^{\circ}$Brix and 11hr. To determine the optimum processing condition by RSm, the polynomial optimum models were established. The regression models was significant (p<0.05). It was used contour plots to optimize osmotic dehydration. The optimum condition for osmotic dehydration as pretreatments for drying of cherry-tomatoes were immersion temperature of 47~53$^{\circ}C$, sugar concentration of 39~43$^{\circ}$Brix, and immersion time of 7hr, in which process conditions were 78~86% moisture content, 8.5~10$^{\circ}$Brix sugar content and 80~86% weight reduction.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.91-95
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• 1999

To investigate the effect of salts on the production of erythritol by Torula sp., cells were grown on the media containing various concentrations of KCl or NaCl. Cell growth and glucose consumption rates decreased when KCl or NaCl concentration increased from 0.0 to 0.5M. The production of erythritol, however, was maximal at 0.3M aCl. The erythritol concentration of 54.3g/l in the medium containing 0.3M NaCl and 200g/l glucose was obtained after 120h. The production of erythritol decreased in cultures above 0.3M NaCl or 0.4M KCl due to the inhibition of cell growth. To elucidate the effect of salts more quantitatively, KCl and NaCl concentrations were converted to osmotic pressure. As the osmotic pressure increased, the yield of erythritol from glucose increased regardless of the kinds of salts and the yield of erythritol was approximately 49% at the osmolality of 2.4Os/kg. When the osmotic pressure increased to 2.5Os/kg, the specific growth rate of cells decreased but the production rate of erythritol increased. For the effective production of erythritol, osmotic pressure must be adjusted not to inhibit markedly the growth rate of cells and to stimulate the production rate of erythritol by supplementing salt.

• Archives of Pharmacal Research
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• v.10 no.2
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• pp.94-99
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• 1987

By using the former equation (8), we modified the equation which can show the dissimilar osmotic behavior of liposome with composition change. The slope of the new equation was presented as the ratio of osmotically active volume (V$_{act}$= ) to the total volume (V$_{totel}$= $_{acl}$+ V$_{dead}$ ; V$_{dead}$ is osmotically inactive volume) of loposomes, we defined is as a Z-value, which can elucidate the dissimilarity of the osmotic activity of multilamellar liposomes with the change of phospholipid composition and the differences of physicochemical properties of liposomes. Z-value was applied for studying the physico-chemical properties of liposomal membrane. The factor that affects on the Z-value was not the lipid concentration of liposome stock dispersion but the lipid composition of liposomal membrane. As the content of dicetylphosphate, the negative charged phospholipid, was increased, the osmotic activity, represented by Z-value, of multilamellar liposome was decreased. Using the hypertonic conditions (shrinking region), Z-value steadily increased and reached a maximum at 10 mole percent cholesterol with increasing the cholesterol content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.903-907
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• 1998

Mass transfer characteristics during osmotic dehydration of mushrooms(Agaricus bisporus) in sugar solution were studied as a function of sugar concentration, immersion time and temperature, and the effect of osmotic dehydration on browning inhibition of air-dried mushrooms was also evaluated. Increasing the sugar concentration, immersion time and temperature increased moisture loss, sugar gain, molality and rate parameter. The changes of sugar gain and rate parameter were more significantly affected by concentration than by temperature of sugar solutions, while 1$0^{\circ}C$ increase in temperature or 10 Brix increase in concentration had the same effect on water loss. Water loss, sugar gain, molality were rapid in the first period of osmotic dehydration especially in the case of higher concentration and temperature of sugar solutions. Effects of osmotic dehydration in sugar solution(60 Brix, 8$0^{\circ}C$) with 18 min of immersion time(O.D.=0.099) rior to air dehydration on browning inhibition of dried mushrooms were more significant than blanching in water(8$0^{\circ}C$) with the same immersion time(O.D.=0.330) and the control (O.D.=0.559).