• Food Science and Biotechnology
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• v.17 no.1
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• pp.8-14
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• 2008

The influence of salt concentration on the stability of sodium caseinate (CAS)-stabilized emulsions (20 wt% corn oil, 3.2 wt% CAS, 5 mM imidazole/acetate buffer, pH 7) was examined. In the absence of salt, laser diffraction measurements and optical microscopy measurements indicated there were some large oil droplets ($d>10\;{\mu}m$) in the emulsions stabilized by 0.8 to 3.2 wt% of CAS. The droplet aggregation (mostly droplet coalescence) observed in the emulsions containing ${\leq}2.8\;wt%$ CAS tended to decrease as the CAS concentration increased, however, after which concentration (at 3.2 wt% CAS) depletion flocculation occurred. The addition of $CaCl_2$ (5-20 mM) into the emulsions stabilized by 3.2 wt% CAS prevented the depletion flocculation although there was a small fraction of relatively large individual droplets in the emulsions, which was attributed to electrostatic screening effect and bridging effect of calcium ion. This study has shown that calcium ion that has been reputed to promote droplet aggregation could improve emulsion stability against droplet aggregation in CAS-stabilized emulsions.

• The Korean Journal of Physiology
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• v.25 no.2
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• pp.159-170
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• 1991

In the rabbit renal artery, mechanisms of contraction by sodium depletion were investigated. The helical strips of isolated renal artery were immersed in the Tris-buffered salt solution. The contractions were recorded isometrically using a strain-gauge transducer. Na-free solution (Na was substituted by Li, choline or sucrose) produced contractions which were dependent on the nature of the Na substitutes. Na-free solution (choline) produced the contraction in ouabain-pretreated artery (Na loaded artery) even in the presence of verapamil. The amplitude of the contraction was dependent on the duration of the pretreatment with ouabain $(10\;^5M)$. Monensin potentiated the effect of ouabain on the contraction. Removal of Ca from bathing solution abolished the contraction and the substitution of Sr for Ca produced the contraction. Divalent cations such as Mg, Mn blocked the depolarization-induced contraction, while they had little effect on the Na-free contraction in Na loaded artery. These results suggest that the contraction induced by Na removal is dependent on the cellular Na content and may be caused by Ca influx via the Na-Ca exchange carrier.

• Corrosion Science and Technology
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• v.3 no.6
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• pp.227-232
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• 2004

The carboxylates as a corrosion inhibitor has been studied by many researchers because of its environmental safety and low depletion rate. However, conventional test methods of inhibitor such as weight loss measurements, linear polarization resistance and corrosion potential monitoring etc., evaluate uniform corrosion of metals. These methods are unable to evaluate crevice-related corrosions, which are encountered in most of heat exchanging facilities. In order to choose the optimum corrosion inhibitor, the appropriate test methods are required to evaluate their performances in service environment. From this point of view, polarization technique was used to evaluate the characteristics of sodium heptanoate on corrosion behavior for carbon steel. Especially a thin film crevice sensor technique were applied to simulate the crevice corrosion in this study. From these experiments, we found that oxygen as an oxidizing agent was required to obtain stable passive film on the metal. Presence of oxygen, however, accelerated crevice corrosion. Potential shift by oxygen depletion and weakened inhibitive film inside the crevice were responsible for such accelerated feature. It is shown that film for corrosion inhibition is a mixture of sodium heptanoate and iron (II) heptanoate as reaction product of iron surface and sodium heptanoate. The iron (II) heptanoate which has been synthesized by reaction of heptanoic acid and ferrous chloride in methanol solution forms bidentate complex.

• Korean Journal of Veterinary Research
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• v.36 no.3
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• pp.571-575
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• 1996

Sulfamethazine sodium was orally administrated to Sprague Dawley female rats(body weight: 200~250g) with the sonde caude at the dose of 20mg of sulfamethazine sodium per 100g of body weight for 3 days to investigate the depletion rate of the drug from liver, kidney and muscle of rat. The results obtained were summerized as follows; 1. The mean concentrations of sulfamethazine in liver according to the time lapsed after oral administration of the sulfamethazine sodium were decreased from 1.27ppm at day 1 to 0.28ppm at day 4. 2. Sulfamethazine concentrations in kidney according to the time lapsed after oral administration of the sulfamethazine sodium were decreased from 0.77ppm at day 1 to 0. 12ppm at day 4. 3. The mean concentration of sulfamethazine in skeletal muscle according to the time lapsed after oral administration of the sulfamethazine sodium was at or below 0.09ppm within 4 days after withdrawl of medicated solution.

• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3517-3527
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• 2021

New 80-MW (electric) ultra-long-life sodium cooled fast reactor core having inherent safety characteristics is designed with heterogeneous fuel assemblies comprised of driver and blanket fuel rods. Several options using upper sodium plenum and SSFZ (Special Sodium Flowing Zone) for reducing sodium void reactivity are neutronically analyzed in this core concept in order to improve the inherent safety of the core. The SSFZ allowing the coolant flow from the peripheral fuel assemblies increases the neutron leakage under coolant expansion or voiding. The Monte Carlo calculations were used to design the cores and analyze their physics characteristics with heterogeneous models. The results of the design and analyses show that the final core design option has a small burnup reactivity swing of 618 pcm over ~54 EFPYs cycle length and a very small sodium void worth of ~35pcm at EOC (End of Cycle), which leads to the satisfaction of all the conditions for inherent safety with large margin based on the quasi-static reactivity balance analysis under ATWS (Anticipated Transient Without Scram).

• Korean Journal of Metals and Materials
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• v.48 no.5
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• pp.410-416
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• 2010

Studies were carried out to establish the technology for sodium-clad compatibility and to analyze the compatibility behavior of the Sodium-cooled Fast Reactor (SFR) cladding material under a flowing sodium environment. The natural circulation facility caused by the thermal convection of the liquid sodium was constructed and the 316-series stainless steels were exposed at $650{^{\circ}C}$ liquid sodium for 1458 hours. The weight change and related microstructural change were analyzed. The results showed that the quasi-dynamic facility represented by the natural convection exhibited similar results compared to the conventional dynamic facility. Selective leaching and local depletion of the chromium, re-distribution of the carbide, and the decarburization process took place in the 316-series stainless steel under a flowing sodium environment. This process decreased as the sodium flowed along the channel, which was caused by the change in the dissolved oxygen and carbon activity in the liquid sodium.

• The Korean Journal of Physiology
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• v.9 no.2
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• pp.33-39
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• 1975

Changes of urinary aldosterone excretion, concurrent sodium and potassium excretion following furosemide administration were studied in normotensive young Korean with high sodium intake, moderate sodium restriction and marked sodium depletion. After intravenous injection of furosemd 40mg, plasma and urine samples were collected at every thirty minutes for two hours. Plasma-and urinary aldosterone, electrolyte concentration and urine flow rate were measured by means of radioimmunoassay or flamephotometry. Relations of urinary aldosterone to concurrent sodium or potassium/sodium ratio, and of urinary aldosterone to concurrent plasma aldosterone activity were studied. Following were the results: 1. Furosemide administration resulted in a increased urinary aldosterone concentration and unchanged or somewhat decreased sodium concentration in course of time after the injection. 2. Urinary potassium concentration showed initial decrease and subsequent increase in course of time after furosemide administration and it resulted in a gradual increase in urinary potassium/sodium ratio. 3. Studying the relations between urinary aldosterone excretion and potassium/sodium excretion ratio, or sodium excretion were meaningless because of the urinary flow rate after the injection was decreased with time course. 4. Furosemide administration showed a good relationship of urinary aldosterone concentration to concurrent potassium/sodium ratio rather than concurrent sodium concentration in subjects with sodium restriction, but no meaningful relationship was detected in subjects with high sodium intake because increasing rate of the ratio was not so wide. 5. Furosemide also resulted a reasonable relation of plasma aldosterone concentration to concurrent urinary aldosterone concentration especially during low sodium intake. 6. Above results suggested that relation of urinary aldosterone concentration to K/Na ratio following furosemide administration during sodium restriction is significant and has a benefit to reduce the variation induced by kalemic change showing in the diragram for daily aldosterone to sodium excretion.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.267-274
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• 2000

Since intracellular free $Mg^{2+}$ ($[Mg^{2+}]_i$) appears to be tightly regulated following cellular energy depletion, we hypothesized that the increase in $[Mg^{2+}]_i$ would result in $Mg^{2+}$ extrusion into circulation. Extracellualr $Mg^{2+}$ contents ($[Mg^{2+}]_o$) were measured in rat erythrocytes, the perfused heart and liver, and plasma in the anesthetized rat. Animals were injected intraperitoneally with sodium nitrite ($NaNO_2$) and plasma $Mg^{2+}$ was measured after the injection and then 10 and 20 minutes later. An increase in circulating (plasma) $Mg^{2+}$ ($[Mg^{2+}]_c$) and methemoglobin was observed in animals injected with $NaNO_2$ (30 mg/Kg). The time course of the effects demonstrated that $[Mg^{2+}]_c$ and methemoglobin continued to increase 10 minutes after the $NaNO_2$ injection. Under these conditions, there was a sustained increase in $[Mg^{2+}]_c$, but not in methemoglobin, which was inhibited by pretreatment with potassium cyanide (KCN, 4 mg/Kg), indicating that an increase in $[Mg^{2+}]_c$ was accompanied by ATP depletion. Injection of rotenone (0.9 mg/Kg) or 2,4-dinitrophenol (15 mg/Kg) also induced an increase in $[Mg^{2+}]_c$. Reduced respiration rate from 100/min to 10/min during 30 minutes also caused a time-dependent rise in $[Mg^{2+}]_c$. These increase in $[Mg^{2+}]_c$ were inhibited by pretreatment with KCN. In addition, ATP depletion by $NaNO_2$ or KCN sustainedly increased the $[Mg^{2+}]_o$ in rat erythrocytes. $Mg^{2+}$ efflux was stimulated by KCN in the perfused heart and liver, but not by $NaNO_2$. These results suggest that the activation of $Mg^{2+}$ effluxes into the circulation is directly dependent on the ATP depletion-induced increase in $[Mg^{2+}]_i$ and heart, liver and erythrocytes have a major pool of $Mg^{2+}$ that can be mobilized upon cellular energy state.

• KSBB Journal
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• v.26 no.5
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• pp.386-392
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• 2011

Human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig), an immunosuppressive agent, was expressed in transgenic rice cells using RAmy3D promoter and RAmy1A signal peptide for the inducible production and secretion into culture media by sugar depletion. In this study, sodium butyrate was used as a small molecular enhancer (SME) to enhance the production of hCTLA4Ig in transgenic rice cell suspension cultures. When 1 mM sodium butyrate was added in sugar-free media, relative viability was not reduced, while the productivity was improved 1.3-fold. In addition, by supplementing 87 mM sodium pyruvate as an alternative energy source during the production phase, death rate of the cells was decreased. When sodium pyruvate was not added, most cells became dead at day 6. However, by adding sodium pyruvate, 18% of viability can be maintained until day 10 and the production of hCTLA4Ig was enhanced 1.4-fold. When the combination of sodium pyruvate and sodium butyrate at optimum concentrations was added, the highest viability and hCTLA4Ig production could be obtained. The highest level of hCTLA4Ig reached up to 35 mg/L at day 10.

• Clinical and Experimental Pediatrics
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• v.50 no.5
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• pp.430-435
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• 2007

Even though we drink and excrete water without recognition, the amount and the composition of body fluid remain constant everyday. Maintenance of a normal osmolality is under the control of water balance which is regulated by vasopressin despite sodium concentration is the dominant determinant of plasma osmolality. The increased plasma osmolality (hypernatremia) can be normalized by the concentration of urine, which is the other way of gaining free water than drinking water, while the low plasma osmolality (hyponatremia) can be normalized by the dilution of urine which is the only regulated way of free water excretion. On the other hand, volume status depends on the control of sodium balance which is regulated mainly by renin-angiotensin-aldosterone system, through which volume depletion can be restored by enhancing sodium retention and concomitant water reabsorption. This review focuses on the urine concentration and dilution mechanism mediated by vasopressin and the associated disorders; diabetes insipidus and syndrome of inappropriate antidiuretic hormone secretion.