• Journal of environmental and Sanitary engineering
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• v.16 no.3
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• pp.14-21
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• 2001

The effects of sodium molybdate(Mo) on phospholipid metabolism in sciatic nerve isolated from lead-intoxicated rat were investigated. Four weeks aged albino rats were divided into four groups : normal control group, lead(10 ppm)-treated group, Mo(1 mg/kg)-treated group, lead and Mo-treated group. As a result of the study, Mo significantly increased the rate of incorporation of $2-[^3H]$myo-inositol into polyphosphinositides in lead-intoxicated rat. Mo also increased the rate of phosphatidylcholine metabolism in normal and lead-intoxicated rats. However, Mo did not affect the metabolism of phosphatidylserine and phosphatidylethanola-mine in normal and lead-intoxicated status. These results suggest that Mo might improve lead-intoxicated status by principally enhancing the metabolism of myo-inositol-related phospholipids and by partly phosphatidylcholine in sciatic nerve.

• Nuclear Engineering and Technology
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• v.41 no.8
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• pp.1115-1126
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• 2009

As one of the ways to enhance the economical features in sodium-cooled fast reactor development, the concept of an integrated steam generator and pump system (ISGPS) is proposed from a structural point of view. And the related intermediate heat transfer system (IHTS) piping layout compatible with the ISGPS is described in detail. To assure the creep design lifetime of 60 years, the structural integrity is investigated through high temperature structural evaluation procedures by the SIE ASME-NH computer code, which implements the ASME-NH design rules. From the results of this study, it is found that the proposed ISGPS concept is feasible and applicable to a commercial SFR design.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.413-418
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• 1998

Intracardiac velocities were determined and the wave-forms described for 4 flow areas of the normal canine heart following administration of chemical restraint drugs including xylazine HCl, ketamine HCl, and thiopental sodium using pulsed wave Doppler echocardiography. The result was that xylazine HCl and thiopental sodium reduced intracardiac flow velocities through mitral, tricuspid, aortic and pulmonary valves. It is also thought that precautions are required before using these drugs. Patterns of wave-forms had no changes between control and treatment groups. Doppler echocardiography allows the clinician to determine flow velocities across the different valves and within the various chambers of the heart. It is shown that establishing normal values and those related to chemical restraint administrations and knowing what influences them should allow the clinician to non-invasively diagnose a variety of pathological cardiac conditions.

• YAKHAK HOEJI
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• v.25 no.1
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• pp.15-25
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• 1981

This study was attempted to investigate the action of debrisoquine, a sympathetic blocking agent presently employed in treating hypertension, on renal function and to elucidate the mechanism of its action. Debrisoquine, given intravenously, elicited increased urine flow, osmolar and free water clearances, along with marked increases in excretion of both sodium and potassium. Glomerular filtration rate also increased, but renal plasma flow tended to decrease, so that the filtration fraction tended to increase. Rates of reabsorption of sodium and potassium in renal tubules were also significantly diminished. The diuresis induced by debrisoquine was completely blocked by treatment with phentolamine and reserpine, and also markedly inhibited by acute renal denervation. Debrisoquine, when injected directly into a renal artery, produced antidiuretic effect and a reduction in urinary excretion of sodium and potassium, along with diminished renal plasma flow and increased filtration fraction. The above observations indicate that debrisoquine, when given intravenously, induces diuresis in the dog as a result of both diminished tubular reabsorption of electrolytes and of renal hemodynamic changes, which seem to be related to its inhibitory action of catecholamine-release from the sympathetic nerve endings.

• Nuclear Engineering and Technology
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• v.54 no.2
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• pp.565-578
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• 2022

Among Generation IV reactors, the sodium-cooled fast reactor (SFR) is attracting attention as a system having great potential for commercial use. Gas entrainment is a thermal-hydraulic issue related to the safety problem of the reactor core in the SFR. Typically, a dipped plate or baffles are installed under the free surface to suppress gas entrainment. However, these approaches can cause gas entrainment in other locations and require many trial-and-error and verifications. In this study, a new strategy using magnetohydrodynamics to suppress gas entrainment in the SFR is proposed. In a counter-flow model, a judgment criterion of gas entrainment occurrence was developed for both water and liquid metal. Moreover, the gas entrainment can be completely suppressed by applying a magnetic field.

• Journal of the Korean Applied Science and Technology
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• v.38 no.4
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• pp.1003-1009
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• 2021

A study on the associative properties of sodium hyaluronate (NaHA) and Alkane-bis (dimethylalkylammonium bromide) surfactants in aqueous solution was investigated in relation to the chemical structure of surfactants. As a result of measuring the interfacial tension, a parabolic graph showing the minimum value (c_min) at a specific concentration was shown. Above this minimum concentration the increase in interfacial tension is thought to be related to the formation of aggregates of NaHA chains and dimeric surfactants. The plot of viscosity vs surfactant concentration shows a slight maxium at c_min and a viscosity decrease at high surfactant concentrations. Viscosity nonlinear behavior is related to the size increase due to the complex growth and to the size shrinkage following from the interaction with electrolyte ions and free micelles. The results of surface tension measurements show a broad region of surface tension decrease, indicating the NaHA-surfactant interaction. The increase in surface tension above c_min may be related to the adsorption of clusters, consisting of free NaHA chains and dimeric surfactant. The strong adsorption of surfactant is observed at high concentrations.

• Korean Journal of Community Nutrition
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• v.17 no.3
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• pp.341-352
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• 2012

It is well established that excessive sodium intake is related to a higher incidence of chronic diseases such as hypertension, stroke, coronary heart disease, cardiovascular disease and gastric cancer. Although the upper limit of the current sodium intake guideline by WHO is set at 2,000 mg/day for adults, sodium intake of Koreans is well over 4,700 mg/capita/day implying an urgent need to develop and implement sodium intake reduction policy at the national level. This study investigated the cost-effectiveness of the sodium intake reduction policy, for the first time, in Korea. Analyses were performed using most recent and representative data on national health insurance statistics, healthcare utilization, employment information, disease morbidity/mortality, etc. The socioeconomic benefits of the policy, resulting from reduced morbidity of those relevant diseases, included lower medical expenditures, transportation costs, caregiver cost for inpatients and income losses. The socioeconomic benefits from diminished mortality included reductions in earning losses and welfare losses caused by early deaths. It is estimated that the amount of total benefits of reducing sodium intake from 4.7 g to 3.0 g is 12.6 trillion Korean Won; and the size of its cost is 149 billion Won. Assuming that the effect of sodium intake reduction would become gradually evident over a 5-year period, the implied rate of average return to the sodium reduction policy is 7,790% for the following 25 years, suggesting a very high cost-effectiveness. Accordingly, development and implementation of a mid-to-long term plan for a consistent sodium intake reduction policy is extremely beneficial and well warranted.

• Clinical Psychopharmacology and Neuroscience
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• v.16 no.4
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• pp.422-433
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• 2018

Objective: Neuropsychiatric manifestations like depression and cognitive dysfunction commonly occur in inflammatory bowel disease (IBD). In the context of the brain-gut axis model, colitis can lead to alteration of brain function in a bottom-up manner. Here, the changes in the response of the hypothalamic-pituitary-adrenal axis and inflammation-related markers in the brain in colitis were studied. Methods: Dextran sodium sulfate (DSS) was used to generate a mouse model of colitis. Mice were treated with DSS for 3 or 7 days and sacrificed. We analyzed the gene expression of brain-derived neurotrophic factor (BDNF), cyclooxygenase 2 (COX-2), and glial fibrillary acidic protein (GFAP), and the expression of GFAP, in the hippocampus, hypothalamus, and amygdala. Additionally, the levels of C-reactive protein (CRP) and serum cortisol/corticosterone were measured. Results: Alteration of inflammatory-related markers varied depending on the brain region and exposure time. In the hippocampus, COX-2 mRNA, GFAP mRNA, and GFAP expression were upregulated during exposure to DSS. However, in the hypothalamus, COX-2 mRNA was upregulated only 3 days after treatment. In the amygdala, BDNF and COX-2 mRNAs were downregulated. CRP and corticosterone expression increased with DSS treatment at day 7. Conclusion: IBD could lead to neuroinflammation in a bottom-up manner, and this effect varied according to brain region. Stress-related hormones and serum inflammatory markers, such as CRP, were upregulated from the third day of DSS treatment. Therefore, early and active intervention is required to prevent psychological and behavioral changes caused by IBD, and region-specific studies can help understand the precise mechanisms by which IBD affects the brain.

• Macromolecular Research
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• v.12 no.6
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• pp.559-563
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• 2004

Both the ultrasonic velocity at 3 MHz and the absorption coefficient in the frequency range from 0.2 to 2 MHz were measured for aqueous solutions of poly(sodium 4-styrenesulfonate) over the concentration range from 5 to $25\%$ (by weight). The pulse echo overlap method was employed to measure the ultrasonic velocity over the temperature range from 10 to $90^{\circ}C;$ the high-Q ultrasonic resonator method was used for the measurement of the absorption coefficient at $20^{\circ}C.$ The velocities exhibited their maximum values at ca. 55, 59, 63, 67, and $71^{\circ}C.$ for the 25, 20, 15, 10, and $5\%$ solutions, respectively. The velocity increased with respect to the poly(sodium 4-styrene-sulfonate) concentration at a given temperature. A study of the concentration dependence of the both the relaxation frequency and amplitude indicated that the relaxation at ca. 200 kHz is related to structural fluctuations of the polymer molecules, such as the segmental motions of the polymer chains and that the relaxation at ca. 1 MHz resulted from the proton transfer reactions of the oxygen sites of $SO_3.$ Both the absorption and the shear viscosity increase upon increasing the polymer concentration, but they decrease upon increasing the temperature.

• Journal of environmental and Sanitary engineering
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• v.9 no.1
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• pp.76-88
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• 1994

This study was carried out to investigate contents of nitrosamine precursors such as trite and dimethylamine( DMA ) in some foods. The diazo and Cu- dithiocarbamate melt were used for determination, respectively. The major affecting factors of Nnitrosodimethylamine( NDMA ) formation such as pH, contents of DMA and NaNO$_{2}$, other chemicals, and UV- ray in beverage were investigated in vitro. The contents of nitrite in meat sausage and meat ham were 6.44 ∼ 18.66ppm and 12.85- 39.95pp% respectively, And extremely low level was detected in a certain kind of fish sausage. The contents of DMA in meat sausage meat ham and fish sausage were 3.34∼15. 85ppm, 1.20∼7.10ppm and 7.38∼12.28ppm, respectively. The optimum pH for NDMA formation in vitro was 3.0. NDMA formation was rapidly occurred at high temperature and formed above 80% within 1 hour reaction. The formation of NDMA was increased in proportion to the concentration of DMA and the square of the nitrite concentration. 0.1 M of sodium citrate, sodium tartarated and sodium taiocyanate enhanced NDMA formation. But sodium chloride did not affect. However, 0.3M of ascorbic acid, erythroid acid, ascorbic, palmitate and propy, gallate inhibited NDMA formalion approximately 78%,81%,86% and 85%, respectively. Cow milk and soybean milk inhibited 35 ∼47% of NDMA formation but orange juice and apple juice enhanced 15 ∼64% of NDMA formation. The peak in HPLC for NDMA disappeared by irradiation of UV to prior formed NDMA This result suggest that NDMA was destroyed by UV irradiation.