• The Korean Journal of Physiology
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• v.23 no.1
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• pp.67-78
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• 1989

Since the atrial receptor was suggested to be involved in the control of extracellular fluid volume, it has been shown that the granularity of atrial cardiocytes can be changed by water and salt depletion, and that an extract of atrial tissue, when injected intravenously into anesthetized rats, causes a large and rapid increase in renal excretions of sodium and water. The immunoreactive atrial natriuretic peptide (ANP) has been found in the plasma of patients suffering from various cardiovascular diseases. A high level of ANP in the plasma has been reported in essential hypertension. Several studies on the effects of ANP on renal function and arterial blood pressure have presented contradictory results showing attenuated or accentuated responses. Thus, involvement of the ANP in the development of hypertension remains unresolved. Present study was undertaken to investigate whether the ANP is involved in the development of hypertension in two-kidney one-clip Goldblatt hypertensive rats. The plasma concentration of immunoreactive ANP appeared to be significantly elevated in hypertensive rats as compared with normotensive Goldblatt operated and sham-operated rats. Plasma renin concentration was higher in hypertensive rats than in normotensive rats, as observed in earlier experiments. Intravenous infusions of ANP resulted in increases of urine flow and urinary excretions of sodium and potassium in both hypertensive and normotensive rats. The renal response to ANP was markedly accentuated in Goldblatt hypertensive rats. The plasma concentration of ANP showed a linear relationship with the arterial blood pressure. Infusions of ANP reduced blood pressure both in hypertensive and normotensive rats. These results suggest that in Goldblatt hypertensive rats an elevation of ANP level in the plasma may not be a cause, but instead a consequence of hypertension, and that the renal responsiveness to the ANP is accentuated by some unknown mechanisms.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.209-213
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• 2011

Hydrophobic silica aerogel beads with low thermal conductivity and high porosity were prepared using a cost-effective sodium silicate as a silica source via an ambient-pressure drying process. Monolithic wet gels were first prepared by adjusting pH (~5) of a diluted sodium silicate solution. The silica aerogel beads (0.5~20 mm) were manufactured by breaking the wet gel monoliths under a simultaneous solvent exchange/surface modification process and an ambient-pressure drying process without using co-precursors or templates. Dried silica aerogel beads exhibit a comparable porosity ($593m^2/g$ of surface area, 34.9 nm of pore size, and $4.4cm^3/g$ of pore volume) to that of the aerogel powder prepared in the same conditions. Thermal conductivity of the silica aerogel beads (19.8 mW/mK at $20^{\circ}C$) is also identical to the aerogel powder.

• Food Science of Animal Resources
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• v.42 no.3
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• pp.441-454
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• 2022

This study aimed to determine the effect of enzyme, guar gum, and pressure processing on the digestibility and physicochemical properties of age-friendly liver sausages. Liver sausages were manufactured by adding proteolytic enzyme (Bromelain) and guar gum, and pressure-cooking (0.06 MPa), with the following treatments: control, without proteolytic enzyme; T1, proteolytic enzyme; T2, proteolytic enzyme and guar gum; T3, pressure-cooking; T4, proteolytic enzyme and pressure-cooking; T5, proteolytic enzyme, guar gum, and pressure-cooking. The pH was high in the enzyme- and pressure-processed groups. The pressure-processed groups had lower apparent viscosity than other cooking groups, and it decreased during enzyme treatment. Hardness was lower in the enzyme- and pressure-processed groups than in the control, and the T4 was the lowest. Digestibility was the highest in T4 at 82.58%, and there was no significant difference with that in T5. The general cooking group with enzyme and guar gum also showed higher digestibility than the control (77.50%). As a result of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the enzyme- and pressure-treated groups (T4, T5) were degraded more into low-molecular-weight peptides (≤37 kDa) than the control and other treatments. Viscoelasticity showed similar trends for viscous and elastic moduli. Similarly, combined pressure processing and enzymatic treatment decreased viscoelasticity, while guar gum increased elasticity but decreased viscosity. Therefore, the tenderized physical properties and improved digestibility by enzyme and pressurization treatment could be used to produce age-friendly spreadable liver sausages.

• Food Science and Preservation
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• v.22 no.6
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• pp.859-866
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• 2015

The purpose of this study was to develop a supplemental healthy food that can help prevent high blood pressure-related diseases caused due to the excessive consumption of sodium in salt. This was achieved by using ion-displacement techniques to produce mineral salt with lower sodium content by using fermented brown rice by-products rich in minerals. Mineral salt containing 2019.2 mg/100 g of potassium, 678.5 mg/100 g of magnesium, 48.7 mg/100 g of calcium, and 19.5 mg/100 g of sodium was obtained by fermenting brown rice by-products to create a culture medium for the mineral salt. Mineral salt containing 1769.7 mg/100 g of potassium, 573.6 mg/100 g of magnesium, 35.3 mg/100 g of calcium, and 19.5 mg/100 g of sodium was obtained by filtering and refining the by-product extract of fermented brown rice. The results showed that when the stream velocity of the instrument used for electrolysis was 200 mL/min and the current and the concentration of the reactive liquid in the purified water chamber were higher, the effect of electrolysis was greater. Ion hot water extraction of the fermented brown rice by-products improved by up to 95% and was collected as purified water within 90 min of the reaction time. Chloride ions with pH 7.4 were produced by mixing sodium hydroxide in a purified saline water chamber with electro-analyzed water. The salt produced in this study contained low sodium, 5.7~30%, as compared to 40% sodium content of the normal salt.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.1
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• pp.20-26
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• 2002

HID(high intensity discharge)lamps include high pressure mercury lamp, high pressure sodium lamp and metal halide lamp. Metal halide lamps have been considered to be one of the most erective light sources. These lamps have good efficiency, good color rendering and good focusing capability. The objective of this research is to alum on the metal halide lamp(MH70W) by the developed electronic ballast with free voltage input(AC 100∼277V). The developed electronic ballast consists of a free voltage input converter, a flyback converter ＆ half-bridge inverter, ignitor ＆ protector and control1er. Experimental results show that developed electronic ballast turns on the metal halide lamp(MH70W) with free voltage input(AC 100∼277V) very well.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.3
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• pp.399-405
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• 2011

In a desalination technology using RO membranes, chemical cleaning makes damage for membrane surface and membrane life be shortened. In this research cleaning technology using direct osmosis (DO) was introduced to apply it under the condition of high pH and high concentration of feed. When the high concentration of feed is injected to the concentrate side after release of operating pressure, then backward flow occurred from treated water toward concentrated for osmotic pressure. This flow reduces fouling on the membrane surface. Namely, flux of DO was monitored under pH 3, 5, 10 and 12 conditions at feed concentrations of NaCl 40,000 mg/L, 120,000 mg/L and 160,000 mg/L. As a result, DO flux in pH 12 increased about 21% than pH 3. DO cleaning was performed under the concentrate NaCl 160,000 mg/L of pH 12 during 20 minutes. Three kinds of synthetic feed water were used as concentrates. They consisted of organic, inorganic and seawater; chemicals of SiO2 (200 mg/L), humic acid (50 mg/L) sodium alginate (50 mg/L) and seawater. As a result, fluxes were recovered to 17% in organic fouling, 15% in inorganic fouling and 14% of seawater fouling after cleaning using DO under the condition of concentrate NaCl 160,000 mg/L of pH 12.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.2
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• pp.145-153
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• 2011

The irradiation tests of materials in HANARO have been performed usually at temperatures below $300^{\circ}C$ at which the RPV(Reactor Pressure Vessel) materials of the commercial reactors such as the light water reactor and CANDU are operated. As VHTR(Very High Temperature Reactor) and SFR(Sodium-cooled Fast Reactor) projects are being carried as a part of the present Gen-IV program in Korea, the requirements for irradiation of materials at temperatures higher than $500^{\circ}C$ are recently being gradually increased. To overcome the restriction in the use at high temperature of the existing Al thermal media, a new capsule with double thermal media composed of two kinds of materials such as Al-Ti and Al-graphite was designed and fabricated more advanced than the single thermal media capsule. At the irradiation test of the capsule, the temperature of the specimens successfully reached $700^{\circ}C$ and the integrity of Al, Ti and graphite material was maintained.

• Journal of the Korean Ceramic Society
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• v.45 no.2
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• pp.87-89
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• 2008

A nano structured silica aerogel thin film was manufactured from inexpensive sodium silicate (water glass) using an ambient pressure drying method. High purity silicic sol was prepared by passing a water glass solution through an ion exchange resin, and the gel films were prepared on a modified glass substrate via dip coating. The dip coating conditions, such as coating time and solvent, were optimized. The optical and physical properties of the obtained silica aerogel thin film were characterized using a UV-visable spectrometer and a scanning electron microscope.

• Journal of agricultural medicine and community health
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• v.30 no.1
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• pp.29-38
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• 2005

Objectives: Hypertension is the most important risk factors for the cerebrovascular diseases, and also for coronary heart diseases, it is therefore very important that the people have a knowledge on nature of hypertension and it's high risk in order to prevent and detect the hypertension as early as possible. Methods: This study was done to find out the knowledge on hypertension of 434 parents of elementary school students from Kimjae city, Jonbuk province, they were parents in grade 4, 5 and 6 attending two elementary schools. The survey took 10 days from November 20 to November 30, 2003. Results: first, The highest correct answer(94.5%) was "obesity is risk factors for hypertension", followed by "hypertension is closely related with hereditary factors(91.0%) and "high sodium intake is associated with high blood pressure"(85.7%). The lowest correct answer(77.4%) was the classification of blood pressure level between normal and high. Second, Rate of blood pressure measurement for fathers was 53.7% and 54.8% in mothers. Awareness of own blood pressure by fathers was 84.1 %, while 91.1% by mothers. Third, According to blood pressure level reported by parents, fathers with normal blood pressure was 59.2%, high normal blood pressure was 12.2%, while hypertension was 28.6%. It revealed that prevalence of hypertension of fathers was higher than mother (normal: 74.5%, high normal: 7.7%, hypertension: 18.2%). Conclusions: From the results of this study, it is important to strengthen the health education about hypertension for community people and also school students.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.144-144
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• 1998

The physiological responses caused by exposure of high- and low-level lead exhibit different phase. Low-level lead continuous hypertension, but high-level lead can in the development of hypertension. In this study it was tested which difference can be caused as lead levels and, if it can be caused, whether hematological changes are related with the hypertensive effects induced by different levels of lead exposure was tested. Lead intoxication in male SD rats was induced by exposure through drinking water containing 50, 200 and 1000 ppm lead (as lead acetate). The animals of control group was supplied drinking water containing sodium acetate ad libitum. The number of each animal group was 10. Systolic blood pressures were measured in the unanesthetized state by the tail-cuff technique at 0, 3, 7 and 16 weeks. RBC, WBC, MCV, hemoglobin, hematocrit and whole blood viscosity levels were examined.