• The Korean Journal of Physiology
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• v.8 no.2
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• pp.19-31
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• 1974

In oder to study the correlation between daily urinary output of sodium chloride and blood pressure, twenty four hour urine samples were collected from 224 cases (70 male and 154 female) of healthy Koreans whose age varied from 18 to 70 years old. The volume and concentration of sodium, chloride and potassium and total nitrogen were measured, along with the resting blood pressure. Results obtained are summarized as follows; 1. Daily urinary output was increased as a function of age. However, daily urinary output per unit sulface area was maintained at approximately 800 to 900 $ml/m^2$ in all age groups of male and it increased as a function of age in female groups. There was no significant difference between male and female. 2. The daily urinary sodium concentration was decreased gradually acceding to age in both sexes. Daily excretion of sodium was constant regardless of age in both sexes but especially high in 25-39 year female age group, which was slightly greater in males than in females. 3. The daily urinary chloride concentration was at approximately 250 meq/L in all age groups of male and which decreased as a function of age in females. 4. Hence the daily urinary output of sodium chloride was constant in all age groups of males which increased as a function of age in female groups. However, daily excretion of sodium chloride per unit sulface area was maintained at approximately 11 $gm/m^2$ in males and which increased as a function of age in females. 5. The daily urinary excretion of potassium was constant regardless of age in both sexes. 6. Urinary K/Na ratio was maintained at approximately 0.27 in males and 0.33 in females. 7. The daily urinary output of total nitrogen amount was approximately $8{\sim}10$ gm in males and $7{\sim}9$ gm in females. However, daily urinary output of nitrogen per unit sulface area was constant regardless of age in both sexes. 8. The systolic blood pressure was increased gradually according to the age in both sexes and was higher for males than females under 40 years of age. However, there was no significant difference between both sexes in ages over 40 years. 9. Quantitative comparisons indicated that daily urinary output and sodium chloride excretion are higher while daily potassium output, nitrogen excretion and urinary K/Na ratio are significantly lower among Koreans than a among Occidentals. These findings suggest that average Koreans live on low-protein and high-salt diet throughout their livers. Statistical result obtained may he summarized as follows; 10. The relation between blood pressure and sodium concentration of urine. The correlation between systolic blood pressure and sodium concentration was negatively associated for both sexes and the correlation coefficient was significant for females $({\gamma}_1=-.19<-{\gamma}_{152},\;_{0.05}=-0.159)$ and it was not significant for males $({\gamma}_1=-.19>-{\gamma}_{68},\;_{0.05}=-0.232)$ tut may be due to the sample size for males. The correlation between diastolic blood Pressure and sodium concentration was negatively associated for both sexes and the correlation coefficient was significant for males $({\gamma}_1=-.37<-{\gamma}_{68},\;0.05=-0.232)$ and the relation was not significant for females $({\gamma}_1=-.11>-{\gamma}_{152},\;_{0.05}=-0.159)$. 11. The relation between blood pressure and daily urinary sodium chloride excretion. The association between systolic blood pressure and sodium chloride excretion was positively correlated for both sexes and the relation was significant for females $({\gamma}_1=.20>{\gamma}_{152},\;_{0.05}= 0.159)$ and it was insignificant for males $({\gamma}_1=.09<{\gamma}_{68},\;_{0.05}=0.232)$, The relation between diastolic blood pressure and sodium chloride excretion was positively associated and insignificant for both sexes males $({\gamma}_1=.17<{\gamma}_{68},\;_{0.05}=0.232)$ and females $({\gamma}_1=.09<{\gamma}_{152},\;_{0.05}=0. 159)$. 12. The relation between daily urinary nitrogen excretion and sodium chloride excretion. The association between daily nitrogen excretion and sodium chloride excretion was positively significant for both sexes, males $({\gamma}_1=.31>{\gamma}\;_{68},\;_{0.05}=0.232)$ and females $({\gamma}_1=.36>{\gamma}_{-152},\;_{0.05}=0.159)$.

• Nutrition Research and Practice
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• v.14 no.5
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• pp.540-552
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• 2020

BACKGROUND/OBJECTIVES: Hypertension is the major risk factor for cardiovascular disease, a leading cause of deaths in Korea. The objective of this study was to evaluate the effect of a nutrition education in reducing sodium intake and increasing potassium intake in hypertensive adults. SUBJECTS/METHODS: Subjects who participated in this study were 88 adults (28 males and 60 females) who were pre-hypertension or untreated hypertensive patients aged ≥ 30 yrs in Gyeonggi Province, Korea. These subjects were divided into 2 groups: a lowsodium education (LS) group and a low-sodium high-potassium education (LSHP) group. Nutrition education of 3 sessions for 12 weeks was conducted. Blood pressure, blood and urine components, nutrient intake, and dietary behavior were compared between the two education groups. RESULT: Blood pressure was decreased in both groups after the nutrition education (P < 0.05). In the LSHP group, levels of blood glucose (P < 0.05), total cholesterol (P < 0.01), and lowdensity lipoprotein-cholesterol (P < 0.05) were decreased after the program completion. Sodium intake was decreased in both groups after the nutrition education (P < 0.05). However, Na/K ratio was only decreased in the LS group (P < 0.05). Intake frequency of fish & shellfish was only significantly reduced in the LS group (P < 0.05), while intake frequencies of cooked rice, noodles & dumplings, breads & snacks, stew, kimchi, and fish & shellfish were reduced in the LSHP group (P < 0.05). Total score of dietary behavior appeared to be effectively decreased in both groups after the education program (P < 0.001). CONCLUSIONS: This education for reducing sodium intake was effective in reducing blood pressure and sodium intake. The education for enhancing potassium intake resulted in positive changes in blood glucose and serum cholesterol levels.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.1
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• pp.27-32
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• 2003

The thesis is used by PSpice circuit model to the characteristics of a fluorescent lamp modified form of he classical Cassie and Mayr equations in order to show the characteristics of HID(High-Intensity Discharge) Lamp. This is useful for applying high-frequency electric ballast for HID Lamp, and show that the result of experimentations and simulations, such as lamp rating, input voltage, high-frequency electric ballast which is using the ABM circuit model of the low pressure sodium lamp, come to the voltage and current wave.

• Industrial Engineering and Management Systems
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• v.3 no.1
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• pp.59-62
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• 2004

The number of tunnel has fast increased with the rapid expansion of highway network. Tunnel should be designed to provide for drivers both safety and pleasant driving conditions. In this perspective, the design for tunnel lightning is very important in order to provide its safety, pleasantness, and cost-efficiency of maintenance, all of which should be considered and analyzed for a better tunnel lighting. This paper attempts to compare the low-pressure sodium lamp, which have usually been used for tunnel lighting, with the fluorescent lamp, which we consider as an alternative for the former. In an effort to determine the number of lamps to meet the required illuminance in the tunnel, this research employs a simulation technique which would allow us to conjecture, with the aid of basic model, the life cycle cost for illumination per each tunnel. This analysis is expected to provide a basic method and related information for tunnel development and design.

• The Korean Journal of Physiology
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• v.23 no.2
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• pp.253-261
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• 1989

Responses of atrial natriuretic peptide (ANP), aldosterone and renin release to acute volume expansion were compared in normotensive Wistar and spontaneously hypertensive rat (SHR) fed low or high-sodium diet (2 or 25 mmol Na/100 g diet). Experimental diets were fed for 6 weeks from 7-week-old and the growth rate was similar in all groups. In the morning of the experiment, catheters were inserted under ether anesthesia in femoral artery for pressure recording and blood collection, femoral vein for saline infusion, and bladder for urine collection. Then, the rats were placed in restraining cages. When the rats were recovered from anesthesia and the arterial pressure became stabilized, control urine and blood samples were collected. Then, 0.9% saline was infused for 30 min for volume expansion (3% BW). Arterial pressure was significantly higher in the high-sodium SHR but there was no difference between the two groups of Wistar rats. Control plasma levels of Na, K, ANP, renin activity, and hematocrit were not different among the 4 groups. However, plasma aldosterone level was significantly higher in the low-sodium groups. Wistar low-sodium rats showed approximately two times higher plasma aldosterone level than the SHR counterpart. Volume expansion produced a marked increase in plasma ANP level, especially in the high-sodium groups. The low-sodium groups of both strains showed approximately two-fold increase in plasma ANP level. Following a volume expansion plasma aldosterone level and renin activity decreased in all groups. There was a significant logarithmic positive correlation between plasma renin activity and aldosterone concentration. The low-sodium rats produced a greater increase in aldosterone release by small increase in plasma renin than did the high-sodium rats. The low- and high-sodium rats produced a similar degree of diuresis and natriuresis after volume expansion. However, SHR produced a greater natriuresis than did the Wistar rats. The above results indicate that regulatory mechanisms of ANP, aldosterone and renin release are different between the normotensive and hypertensive rats, and between the low- and high-sodium groups.

• Geomechanics and Engineering
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• v.16 no.1
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• pp.71-83
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• 2018

Compacted bentonites were chosen as the backfill material and buffer in high level nuclear waste disposal due to its high swelling pressure, high ion adsorption capacity and low permeability. It is essential to estimate the swelling pressure in design and considering the safety of the nuclear repositories. The swelling pressure model of expansive clay colloids was developed based on Gouy-Chapman diffuse double layer theory. However, the diffuse double layer model is effective in predicting low compaction dry density (low swelling pressure) for certain bentonites, and invalidation in simulating high compaction dry density (high swelling pressure). In this paper, the new relationship between nondimensional midplane potential function, u, and nondimensional distance function, Kd, were established based on the Gouy-Chapman theory by considering the variation of void ratio. The new developed model was constructed based on the published literature data of compacted Na-bentonite (MX80) and Ca-bentonite (FoCa) for sodium and calcium bentonite respectively. The proposed models were applied to re-compute swelling pressure of other compacted Na-bentonites (Kunigel-V1, Voclay, Neokunibond and GMZ) and Ca-bentonites (FEBEX, Bavaria bentonite, Bentonite S-2, Montigel bentonite) based on the reported experimental data. Results show that the predicted swelling pressure has a good agreement with the experimental swelling pressure in all cases.

• Journal of Animal Science and Technology
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• v.64 no.2
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• pp.218-234
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• 2022

Urbanization is usually followed by changes in eating habits, with a specific trend toward the consumption of ready-to-eat products, such as processed foods. Among the latter, meat products are known contributors to high dietary sodium owing to salt addition. Salt plays an essential role in maintaining the quality of meat products in terms of acceptability and safety. However, an excessive salt intake is linked to high blood pressure and cardiovascular diseases. Hence, several studies have been competing for the discovery of salt alternatives performing in a similar way as common salt. A number of replacements have been proposed to reduce salt consumption in meat products while taking into account consumer preferences. Unfortunately, these have resulted in poorer product quality, followed by new adverse effects on health. This review addresses these recent issues by illustrating some established approaches and providing insight into further challenges in developing low-salt meat products.

• The Korean Journal of Physiology
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• v.24 no.2
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• pp.319-329
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• 1990

Effects of atrial natriuretic peptide (ANP) on blood pressure, plasma lenin activity, aldosterone and renal excretion were compared in conscious spontaneously hypertensive rats (SHR) and normotensive Wistar rats fed low, medium or high sodium diet (2, 10, 25 mmol NaCl/100g diet) for 6 weeks. ANP infusion (380 ng/kg/min for 20 min) produced reductions in blood pressure, plasma renin activity, and aldosterone level, but marked increases in hematocrit, urine flow, and excretions of sodium and potassium. The low sodium group showed a significantly enhanced aldosterone lowering effect of ANP than the high sodium group. However, three salt groups showed no difference in effects of ANP on blood pressure, plasma renin activity, hematocrit and diuresis. Natriuretic response to ANP was significantly greater in the high salt-than in the low sait-SHR, but was not different between the Wistar salt groups. There were strain differences in effects of ANP: SHR showed greater responses of blood pressure and natriuresis than Wistar rats. Above results indicate that aldosterone-lowering and natriuretic effects of ANP were modifed by different dietary sodium intakes. However, blood pressure- and renin-lowering, or diuretic effects of ANP were not affected by dietary sodium intakes. The mechanisms whereby dietary sodium intakes alter the effects of ANP in the pathogenesis of hypertension are not clear.

• Journal of Mechanical Science and Technology
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• v.15 no.11
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• pp.1533-1540
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• 2001

A high-temperature sodium stainless steel heat pipe was fabricated and its performance has been investigated. The working fluid was sodium and it was sealed inside a straight tube container made of stainless steel. The amount of sodium occupied approximately 20% of the total volume of the heat pipe and its weight was 65.7gram. The length of a stainless steel container is 1002mm and its outside diameter is 25.4mm. Performance tests were carried out in a room air condition under a free convective environment and the measured temperatures are presented. The start-up behavior of the heat pipe from a frozen state was investigated for various heat input values between 600W and 1205W. In steady state, axial temperature distributions of a heat pipe were measured and its heat transfer rates were estimated in the range of vapor temperature from 50$0^{\circ}C$ to 63$0^{\circ}C$. It is found that there are small temperature differences in the vapor core along the axial direction of a sodium heat pipe for the high operating temperatures. But for the range of low operating temperatures there are large temperature drops along the vapor core region of a sodium heat pipe, because a small vapor pressure drop makes a large temperature drop. The transition temperature was reached more rapidly in the cases of high heat input rate for the sodium heat pipe.

• The Korean Journal of Nuclear Medicine
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• v.9 no.1
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• pp.21-29
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• 1975

Radioimmunoassay for the measurement of plasma renin activity (PRA) was performed in 43 normal Koreans and 45 patients with essential hypertension. Plasma samples were drawn in supine position in the morning and after upright posture for 4 hours. Urinary sodium excretion rates were measured in the concurrent 24 hour urine samples, as an index of their sodium balance. The results were as follows: 1. There was an inverse correlation between 24hr sodium excretion and PRA. The normal values of PRA in supine position ranged from 1.0 to 7.0 ng/ml/hr. when 24 hour sodium excretion were between 50 to 150 mEq. PRA in elderly tended to be low. 2. When stimulated by 4 hour upright posture, PRA increased by 2.6 times from the baseline value. 3. Of the 45 patients with essential hypertension, PRA was low in 10 cases (22.2%), normal in 28 cases (62.2%), and high in 7 cases (15.6%). 4. In the normal and high renin groups, who tended to be younger in ages, mean diastolic blood pressure and BUN were higher than in low renin group. Though hypertensive retinopathy and left ventricular hypertrophy in ECG were more prevalent in the former, no significant differences were noted as in the case of serum cholesterol. 5. There were 8 cases of cardiovascular complications (7 with cerebral vascular accident, 1 with myocardial infarction); 3 in low renin group (30%), 2 in normal renin (7.1%) and 3 in high renin group (42.9%). This figure indicated higher rate of cardiovascular complications in high renin groups, and lower rate in normal renin group. But the incidence of the complication was not significantly low in low renin group.