• Title/Summary/Keyword: Osmotic effect

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Assessing the anion type effect on the hydro-mechanical properties of smectite from macro and micro-structure aspects

  • Goodarzi, Amir R.;Akbari, Hamid R.
    • Geomechanics and Engineering
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    • v.7 no.2
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    • pp.183-200
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    • 2014
  • The expansivity of clayey soils is a complicated phenomenon which may affect the stability of geotechnical structures and geo-environmental projects. In all common factors for the monitoring of soil expansion, less attention is given to anion type of pore space solutions. Therefore, this paper is concerned with the impact of various concentrations of different inorganic salts including NaCl, $Na_2SO_4$, and $Na_2CO_3$ on the macro and microstructure behavior of the expandable smectite clay. Comparison of the responses of the smectite/NaCl and smectite/$Na_2SO_4$ mixtures indicates that the effect of anion valance on the soil engineering properties is not very pronounced, regardless of the electrolyte concentration. However, at presence of carbonate as potential determining ions (PDIs) the swelling power increases up to 1.5 times compared to sulfate or chloride ions. The samples with $Na_2CO_3$ are also more deformable and show lower osmotic compressibility than the other mixtures. This demonstrates that the barrier performance of smectite greatly decreases in case of anions with the non-specific adsorption (e.g., $Cl^-$ and $SO{_4}^{2-}$) as the salinity of solution increases. Based on the results of the X-ray diffraction and sedimentation tests, the high soil volumetric changes upon exposure to carbonate is attributed to an increase in the repulsive forces between smectite basic unit layers due to the PDI effect of $CO{_3}^{2-}$ and increasing the pH level which enhance the buffering capacity of smectite. The study concluded that the nature of anion through its influence on the re-arrangement of soil microstructure and osmotic phenomena governs the hydro-mechanical parameters of expansive clays. It seems not coinciding with the double layer theory of the Gouy-Chapman double layer model.

Effect of Osmotic Pressure on hCTLA-lg Production in Transgenic Rice Cell Suspension Cultures (형질전환된 벼세포 배양에 있어서 삼투압 조절에 따른 hCTLA4-lg 생산성 변화)

  • Choi Sung-Hun;Lee Song-Jae;Hong Seok-Mi;Cho Ji-Suk;Kim Dong-Il
    • KSBB Journal
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    • v.20 no.4
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    • pp.278-284
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    • 2005
  • An immunosuppressive agent, human cytotoxic T lymphocyte antigen 4 (hCTLA4), is used for the prevention of graft rejection and treatment of autoimmune diseases. hCTLA4-Ig, a CTLA4-immunoglobulin fusion protein, was produced and secreted from transgenic rice cell suspension cultures using rice a-amylase (RAmy3D) expression system. In this system, hCTLA4-Ig expression was regulated metabolically by sugar starvation. For the purpose of improving hCTLA4-Ig production, the effects of osmotic pressure was investigated in suspension cultures of transgenic rice cells. The highest production level was achieved at 40 mM sorbitol $(140\;mOsm{\cdot}kg^{-1}\;H_2O)$. Using the medium with 8 mM glucose, the level of hCTLA4-Ig in the medium reached 45.3 mg/L. By adjusting the osmotic pressure of induction medium, it was found that the hCTLA4-Ig production could be increased up to 2.1-fold compared with that in batch culture.

Effect of Hypo-osmotic Swelling (HOS) Test on Subsequent Post-thaw Testicular Spermatozoa (고환조직 동결-융해 후 회수된 고환 정자에 대한 Hypo-osmotic Swelling (HOS) Test의 효과)

  • Park, Yong-Seog;Lee, Hyoung-Song;Song, Sang-Jin;Kim, Jeong-Wook;Kang, Inn-Soo;Seo, Ju-Tae
    • Clinical and Experimental Reproductive Medicine
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    • v.27 no.3
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    • pp.267-273
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    • 2000
  • Objectives: We have previous reported that thawed testicular sperm and sperm extracted from seminiferous tubule could achieved optimal fertilization and pregnancy in azoospermic patients. However, thawed testicular sperm did not show motility in many cases. Therefore we studied viability of immotile sperm extracted from frozen-thawed seminiferous tubule using hypo-osmotic swelling (HOS) test and eosin-Y test. Materials and Methods: After sperm extraction using for ICSI, the remained sections of seminiferous tubules were frozen with a computerized freezer. For thawing and preparation of testicular sperm, the seminiferous tubules were thawed by removing from $LN_2$ and letting them at room temperature for 10 min followed by %37^{\circ}C$ water bath for 10 min. The prepared samples were washed for free of preservation medium and sperm preparation method described previous. Sperm was suspended in 0.1 ml hypoosmotic solution. After 30 minutes, the type of distally coiled sperm were assessed. Results: In 44 cases of cryopreservation of seminiferous tubules in obstructive azoospennic patients, the fertilization rates with 2PN were 71.4% and pregnancy rates were 34.1%. The presence of motile spermatozoa on subsequent post-thaw testicular sperm remarked 15.1% and were increased to 77.3% just before ICSI. After sperm extracted from frozen-thawed seminiferous tubule, 3 hrs later in in vitro culture, the cases of presence of motile sperm, reaction of hypo-osmotic swelling test and viable sperm were 63.6% (28/44), 93.2% (41/44), and 77.3% (34/44), respectively. Conclusions: Just after post-thawed testicular sperm did not showed motility. Although motility was gained after in vitro culture, many cases showed non-motile sperm until optimal insemination time. However, HOS test showed positive reaction in non-motile sperm. Therefore, HOS test is an alternative method for the selection of viable sperm for ICSI.

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Effect of Water-Soluble Carriers on Water-Absorption and Swelling of Polydimethylsiloxane-5-Fluorouracil Devices

  • O, Sung-Il;Lee, Chi-Young;Kim, Sung-Ho
    • Journal of Pharmaceutical Investigation
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    • v.16 no.3
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    • pp.101-105
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    • 1986
  • The changes of water absorption and surface area of polydimethylsiloxane-5-fluorouracil devices containing different water soluble additives such as sodium chloride, glycerine, poly-propylene glycol(PPG 400), and polyethylene oxide(PEO 400, 400 and 2000) were investigated. It was confirmed that carriers controlled water absorption and swelling of the devices in the aqueous solutions. The water absorption and the swelling were affected by the osmotic pressure and ionic strength of the aqueous solutions.

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Studies on the hemolytic action of chlorpromazine (Chlorpromazine 의 용혈작용(溶血作用)에 관(關)한 연구(硏究))

  • Kim, Kyu-Tae
    • The Korean Journal of Pharmacology
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    • v.3 no.1
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    • pp.31-41
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    • 1967
  • The author studied the hemolytic action of chlorpromazine on rabbit erythrocytes and obtained the following results: 1. Chlorpromazine caused hemolysis in vitro. The hemolytic action of chlorpromazine was milder than that of saponin(Colleman and Bell Co ) 2. Cholesterol had no marked effect on chlorpromazine hemolysis. 3. Dextrose, albumin and blood plasma protected erythrocytes against chlorpromazine hemolysis. 4. The mechanism of chlorpromazine hemolysis seemed to be different from that of saponin hemolysis. 5. Chlorpromazine increased tile osmotic fragility of rabbit erythrocytes. 6. The intravenous injection of chlorpromazine caused hemolysis in vivo.

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Influence of Septic in Vibrio Vulnificus from Phytic Acid (피틴산(Phytic acid)이 비브리오(Vibrio vulnificus) 패혈증에 미치는 영향)

  • Chung, Young-Ho;Cho, Chun-Hwi;Lee, Sun-Woo;Lim, Chi-Hwan
    • Korean Journal of Agricultural Science
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    • v.32 no.1
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    • pp.71-80
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    • 2005
  • Phytic acid chelates excellently the metallic ions and the positive ions, especially has high affinity with $Fe^{2+}$ and $Ca^{2+}$. Merits of phytic acid can be taked in easily, edibile and harmless to body, so it was investigated that phytic acid can be substituted for EDTA in this study. 1. The Intensificative effect of chelating agent and disinfective osmotic shock of Vibrio vulnificus The number of initial existent fungi measured $1.7{\times}10^6$. The percentages of the survival fungi against the osmotic shock by distillated water were calculated at 1 minute, 3 minute and 5 minute after inoculation. The percentages of the survival fungi in $Mg^{2+}$ were 92.5%, 91.8% and 79.8% at each time, the average percentage was 88%. Also the sudden extinction was observed around 1 minute after inoculation and the survival fungi were not observed from 3 through 5 minute in spite of repeated experimentation. 2. Influence of Vibrio vulnificus on the survival of the mice. The first mouse started to die in 180 minute after inoculation in case that the inoculating number was $2.3{\times}10^7cfu/ml$. All died within 4.5 hour. The average of survival time was 226 minute. The first mouse started to die in 228 minute after inoculation in case that the inoculating number was $0.8{\times}10^6cfu/ml$. All died within 5 hour. The average of survival time was 300 minute and the survival time was 1.3 times high. The tendencies of death in two cases were similar, but the fatal rate were largely dependent on inoculating number.

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Effect of Pretreatments on the Drying Characteristics of Dried Vegetables (전처리 방법에 따른 채소류의 열풍건조특성)

  • Youn, Kwang-Sup;Bae, Dong-Ho;Choi, Yong-Hee
    • Korean Journal of Food Science and Technology
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    • v.29 no.2
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    • pp.292-301
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    • 1997
  • In drying process, to minimize the quality degradation by improved drying process and pretreatment methods, carrots, cabbages and radishes were dried and rehydrated. Physico-chemical properties of product were analyzed to determine the optimum pretreatment method and drying models were applied to explain drying mechanisms. Microwave, steam and water were used prior to drying as blanching method. In consideration of physical properties, optimum treatment time was decided that microwave was 1 min, steam and water were each 10 min. Control, steam, water, microwave and osmotic dehydration were treated prior to drying as pretreatment individually, osmotic dehydration was lower than the other treatmemt in drying efficiency, but carotene content was higher than the others. The effect continued after rehydration. Ten panelists tested dried and rehydrated carrots. After rehydration, the quality of air dried product with osmotic dehydration was superior to freeze dried without treatment. The fittness of drying models were conducted in order to explain the mechanism of drying each process. Quadratic model was most fittable to explain during drying. However, in rehydration process, no fittable model was found.

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Effects of Arachidonic Acid on the Calcium Channel Current $(I_{Ba})$ and on the Osmotic Stretch-induced Increase of $I_{Ba}$ in Guinea-Pig Gastric Myocytes

  • Xu, Wen-Xie;Kim, Sung-Joon;So, In-Suk;Suh, Suk-Hyo;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.4
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    • pp.435-443
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    • 1997
  • We employed the whole-cell patch clamp technique to investigate the effects of arachidonic acid (AA) on barium inward current through the L-type calcium channels ($I_{Ba}$) and on osmotic stretch-induced increase of $I_{Ba}$ in guinea-pig antral gastric myocytes. Under isosmotic condition, AA inhibited $I_{Ba}$ in a dose-dependent manner to $91.1{\pm}1.4,\;72.0{\pm}3.2,\;46.0{\pm}1.8,\;and\;20.3{\pm}2.3%$ at 1, 5, 10, 30 mM, respectively. The inhibitory effect of AA was not affected by 10 ${\mu}M$ indomethacin, a cyclooxygenase inhibitor. Other unsaturated fatty acids, linoleic acid (LA) and oleic acid (OA) were also found to suppress $I_{Ba}$ but stearic acid (SA), a saturated fatty acid, had no inhibitory effect on $I_{Ba}$. The potency sequence of these inhibitory effects was AA ($79.7{\pm}2.3%$) > LA ($43.1{\pm}2.7%$) > OA ($14.2{\pm}1.1%$) at 30 ${\mu}M$. On superfusing the myocyte with hyposmotic solution (214 mOsm) the amplitude of $I_{Ba}$ at 0 mV increased ($38.0{\pm}5.5%$); this increase was completely blocked by pretreatment with 30 mM AA, but not significantly inhibited by lower concentrations of AA (1, 5 and 10 ${\mu}M$) (P>0.05). Unsaturated fatty acids shifted the steady-state inactivation curves of $I_{Ba}$ to the left; the extent of shift caused by AA was greater than that caused by LA. The activation curve was not affected by AA or LA. The results suggest that AA and other unsaturated fatty acids directly modulate L-type calcium channels and AA might modulate the hyposmotic stretch- induced increase of L-type calcium channel current in guinea-pig gastric smooth muscle.

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Changes of Free Sugar and Organic Acid in the Osmotic Dehydration Process of Apples (사과의 삼투건조시 유리당과 유기산의 변화)

  • Youn, Kwang-Sup;Lee, Jun-Ho;Choi, Yong-Hee
    • Korean Journal of Food Science and Technology
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    • v.28 no.6
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    • pp.1095-1103
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    • 1996
  • In order to minimize the deterioration of dried apple quality, changes of free sugar content, organic acid and ascorbic and during osmotic dehydration with sucrose at various temperature, concentration and immersion time were investigated in this study, total sugar increased as the temperature, concentration and immersion time were increased. Sucrose showed the largest change in content while fructose and glucose showed no and small changes, respectively. Large amounts of malic and fumaric acids, and small amounts of oxalic, citric, maleic and succinic acids were detected. Organic acids were high at low temperature treatment, and became higher with increasing concentration. Loss of ascorbic acid was small at the low temperature and high concentration. Effect of immersion time was negligible. Changes of free sugar, and organic and ascorbic acid followed the first-order and second-order reaction rate equations, respectively. Arrhenius equation was applied to determine the effect of temperature on reaction rate constants with high $r^2$. To predict the changes of quality, a model was established by using the optimum functions of temperature, concentration and immersion time. The model had high $r^2$ value for the quality changes during drying.

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Effect of Osmotic Dehydration and Vacuum Impregnation on the Quality of Dried Apple (삼투건조와 진공주입이 사과 건조제품의 품질에 미치는 영향)

  • Choi, Hee-Don;Lee, Hae-Chang;Kim, Yun-Sook;Choi, In-Wook;Park, Yong-Kon;Seog, Ho-Moon
    • Korean Journal of Food Science and Technology
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    • v.40 no.2
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    • pp.178-183
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    • 2008
  • This study investigated the effects of osmotic dehydration (OD) and vacuum impregnation (VI) on the quality of dried apple products. Weight reduction and water loss increased during OD, but these decreased in the apples during VI. In particular, VI's effect on increasing solid gain was superb. For apples in 40% sucrose solution, OD and VI were followed by hot-air drying at 50$^{\circ}C$. The experimental data were fitted successfully using the modified Page model. OD and VI increased drying time and decreased the drying rate constant of these apples as compared to the control. Shrinkage and rehydration capacity greatly decreased in the apples dried by OD and increased in the apples dried by VI as compared to the control. OD also decreased titratable acidity and ascorbic acid content considerably. Sensory evaluations of the products indicated that the apples prepared by OD had higher palatability in their rehydrated form in yoghurt, and the apple products prepared by VI had higher palatability in their dried form.