• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.72-75
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• 2004

The potential of electrokinetic (EK) technology has been successfully demonstrated for the remediation of heavy metal contaminated fine-grained soils through laboratory scale and field application studies. Arsenic contamination in soil is a serious problem affecting both site use and groundwater quality. The EK technology was evaluated for the removal of arsenic from two soil samples: kaolinite clay artificially contaminated with arsenic and arsenic-bearing tailing soil taken from the Myungbong (MB) mining area. The effect of cathodic electrolyte on the process was investigated using three different types of electrolyte: deionized water (DIW), potassium phosphate (KH$_2$PO$_4$) and sodium hydroxide (NaOH). The result of experiments on the kaolinite clay shows that the potassium phosphate was most effective in extracting arsenic, probably resulting from anion exchange of arsenic species by phosphate. On the contrary, the sodium hydroxide seemed to be most efficient in removing arsenic from the tailing soil, and it is explained by the fact that sodium hydroxide increased the soil pH and accelerated ionic migration of arsenic species through increase in desorption and dissolution of arsenic species into pore water.

• Journal of the Korean institute of surface engineering
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• 제44권2호
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• pp.44-49
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• 2011

The films formed on AZ31B magnesium alloy were prepared from alkaline solution composed of potassium permanganate and sodium hydroxide. The immersion tests were carried out at the different concentration of sodium hydroxide and pre-treatment method in 5 minute. The morphology and the phase composition of the film were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The corrosion behavior of the film in 5.0% NaCl solution was evaluated using potentiodyanmic polarization. Open circuit potential in developing film was examined with time. The thin and transparent film was mainly composed of MgO and $Mg(OH)_2$. The film with the best corrosion resistance was obtained at $70^{\circ}C$ bath temperature, 1.6 M concentration of sodium hydroxide and chemical pre-treatment.

• Journal of Periodontal and Implant Science
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• 제1권1호
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• pp.2.1-2.1
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• 1971

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1993년도 제45차 추계 학술대회 연제집
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• pp.31-32
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• 1993

• The Korean Journal of Physiology and Pharmacology
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• 제7권2호
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• pp.73-77
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• 2003

The effects of nitric oxide on the vestibular function recovery following unilateral labyrinthectomy (UL) were studied. Sprague-Dawley male rats, treated with nitric oxide liberating agent sodium nitroprusside (SNP) and NOS inhibitor $N^G$-nitro-L-arginine methyl ester (L-NAME), were subjected to destruction of the unilateral vestibular apparatus, and then spontaneous nystagmus was observed in the rat. To explore the effects of nitric oxide on the neuronal excitability, whole cell patch clamp technique was applied on isolated medial vestibular nuclear neurons. The frequency of spontaneous nystagmus in SNP treated rats was lesser than that of spontaneous nystagmus in control animals. In contrast, pre-UL treatment with L-NAME resulted in a significant increase in spontaneous nystagmus frequency. In addition, SNP increased the frequency of spontaneous action potential in isolated medial vestibular nuclear neurons. Potassium currents of the vestibular nuclear neurons were inhibited by SNP. After blockade of calcium dependent potassium currents by high EGTA (11 mM) in a pipette solution, SNP did not inhibit outward potassium currents. 1H-[1,2,4] oxadiazolo [4,3-a] quinozalin-1-one (ODQ), a specific inhibitor of soluble guanylyl cyclase, inhibited the effects of SNP on the spontaneous firing and the potassium current. These results suggest that nitric oxide after unilateral labyrinthectomy would help to facilitate vestibular compensation by inhibiting calcium-dependent potassium currents through increasing intracellular cGMP, and consequently would increase excitability in ipsilateral vestibular nuclear neurons.

• Asian-Australasian Journal of Animal Sciences
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• 제24권6호
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• pp.844-850
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• 2011

This study was conducted to compare the effects of dietary supplementation of Sodium Gluconate (SG), Mannan Oligosaccharide (MOS) and Potassium Diformate (PDF) on growth performance and small intestinal morphology in nursery piglets. One hundred forty four female piglets ($11.69{\pm}0.71\;kg$) were divided into 4 treatments with six replicates of six pigs each. The pigs received a control diet or diets supplemented with SG, MOS and PDF at 2,500, 3,000 and 8,000 ppm; respectively, for 6 weeks. Supplementation of SG, MOS or PDF increased final body weight, average daily gain and tended to improve feed to gain ratio (p = 0.02, 0.04 and 0.16; respectively), other than average daily feed intake, intestinal pH and the bacterial populations were not influenced by the dietary treatments. SG significantly decreased the ammonia concentration in the caecum (p<0.05) and supplementation of SG, MOS or PDF tended to increase lactic acid and total short chain fatty acid concentration in the caecum (p = 0.08, 0.09; respectively), in addition SG, MOS or PDF slightly increased butyric acid concentration in the caecum (p = 0.14). SG highly significant increased the villous height in jejunum (p<0.01) and supplementing SG, MOS or PDF significantly increased crypt depth in jejunum (p<0.05), moreover, PDF significantly increased villous height and crypt depth ratio in jejunum (p<0.05) compared with control. The dietary treatments did not influence villous height and crypt depth in duodenum and villous height in jejunum (p>0.05). It can be concluded that supplementing SG, MOS or PDF as a feed additive has the potential to improve the growth performance, the intestinal lactic acid bacteria population, intestinal short-chain fatty acid concentration and the intestinal morphology of pigs.

• Journal of the Korean Society of Food Science and Nutrition
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• 제11권2호
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• pp.27-30
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• 1982

The effect of magnesium on the electrolytes distribution and transport in mice was studied using isocalorie and isonitrogenous diets added magnesium salt. The results are summarized as follows: 1. The body weight was the highest value in group C fed with basal diet and 0.4 mg of magnesium per day rather than others. 2. In blood plasma tile content of sodium of group B was higher than others in both male and female. The content of potassium of group B was higher than others in female, and the content of calcium of group B in female and group D in male was higher than others in blood plasma. 3. In case of muscle the content of sodium of group B was higher than others in both male and female. The content of potassium of group B was higher than others in female, but of group C was higher than others in male. The content of calcium of group B was higher than others in female, but of group D was higher than others in male. 4. Magnesium effect on the distribution electrolytes such as sodium, potassium and calcium ions in muscle and blood vessel.

• Korean Journal of Environmental Biology
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• 제18권2호
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• pp.255-262
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• 2000

This study was carried out to investigate the physiological changes induced acutely with the low doses of lead acetate in the synaptosomes from the cerebrum and brain stem of the rat. The general uptake patterns of [$^3$H]-serotonin were observed in synaptosomes, as a model of presynaptic nerve terminal, from the cerebrum and brain stem. And the effects of the low doses of lead acetate on the uptake process were investigated id vitro and in vivo. The Km value of the uptake of the [$^3$H]-serotonin by the synaptosomes was 0.5 $\mu$M in the cerebrum and 0.1 $\mu$M in the brain stem. These low values reveal that the synaptosomes from the cerebrum and the brain stem have a high affinity to [$^3$H]-serotonin, especially in brain stem. The uptake of $\mu$M-serotonin was dependant on the sodium and potassium ions. When being treated with ouabain, the $Na^+$ $-K^+$ ATPase inhibitor, the uptake of [$^3$H]-serotonin was reduced. This supports strongly that the uptake of [$^3$H]-serotonin was sensitive to the changes of the concentrations of the sodium and potassium ions. When the calcium channel blocker, verapamil, was treated, the uptake of [$^3$H]-serotonin was changed only in synaptosomes from the brain stem. The uptake of [$^3$H]-serotonin was reduced by the lead treatment in the synaptosomes from the cerebrum and brain stem in vitro and in vivo. [lead acetate, synaptosomes, $^3$H-serotonin, rat]

• Nutrition Research and Practice
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• 제3권3호
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• pp.212-219
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• 2009

This study was performed to investigate the association between hair mineral levels and nutrient intakes, age, and BMI in female adults who visited a woman's clinic located in Seoul. Dietary intakes were assessed by food frequency questionnaire and mineral levels were measured in collected hairs, and the relationship between these was examined. The average daily nutrient intakes of subjects were compared to those of the KDRIs, and the energy intake status was fair. The average intake of calcium in women of 50 years and over was 91.35% of KDRls and the potassium intake was greatly below the recommended levels in all age groups. In the average hair mineral contents in subjects, calcium and copper exceeded far more than the reference range while selenium was very low with 85.19% of subjects being lower than the reference value. In addition, the concentrations of sodium, potassium, iron, and manganese in the hair were below the reference ranges in over 15% of subjects. The concentrations of sodium, chromium, sulfur, and cadmium in the hair showed positive correlations (P < 0.05) with age, but the hair zinc level showed a negative correlation (P < 0.05) with age. The concentrations of sodium, potassium, chromium, and cadmium in the hair showed positive correlations (P < 0.05) with BMI. Some mineral levels in subjects of this study showed significant correlations with nutrient intakes, but it seems that the hair mineral content is not directly influenced by each mineral intake. As described above, some hair mineral levels in female adults deviated from the normal range, and it is considered that nutritional intervention to control the imbalance of mineral nutrition is required. Also, as some correlations were shown between hair mineral levels and age, BMI, and nutrient intakes, the possibility of utilizing hair mineral analysis for specific purposes in the future is suggested.

• The Korean Journal of Physiology
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• 제9권1호
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• pp.1-11
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• 1975

The present experiments were carried out to investigate the active center of sodium and potassium ion activated adenosine triphosphatase. An ATPase, activated by sodium ion Plus potassium ion in the presence of magnesium ion, and inhibited by ouabain, has been obtained from rabbit red cell ghosts. The ATPase activity was measured by inorganie phosphate released from ATP. From this values of the measured inorganic phosphate, the activity of ATPase was calculated. The following results were observed. 1. The activity of $(Na^++K^+)-ATPase$ is inhibited by ouabain. This effect may not be due to an effect on sulfhydryl groups, amino groups, carboxyl groups, imidazole groups and hydroxyl groups. 2. The $(Na^++K^+)$-activated enzyme system is inhibited by p-chloromercuribenzoate and by d nitroflurobenzene, and this effect may be due to an effect on sulfhydryl groups. These results indicate that the sulfhydryl groups is attached to sodium-potassium dependent adenosine triphosphate, an aspect of the pump. 3. The $(Na^++K^+)-activated$ enzyme system is inhibited by maleic anhydride and this inhibition is reversed by lysine. This Seems to indicate that the active center of this enzyme is the amino groups. 4. The $(Na^++K^+)$-activated enzyme system is inhibited by iodoacetamide and this inhibition is reversed by the simultaneous present of cysteine and aspartic acid in the suspension medium. This result indicates that this enzyme contains sulfhydryl groups and carboxyl groups. 5. The $(Na^++K^+)-ATPase$ activity is accelerated by adrenaline and this effect is abolished by aspartic acid. This effect of aspartic acid indicate that carboxyl group might be involved in the hydrolysis of ATP by the enzyme system. On the hydrolysis of ATP by the enzyme system. On the basis of these experiments it f·as suggested that the active center of $(Na^++K^+)-activated$ ATPase contains sulfhydryl groups, amino groups and carboxyl groups.