• Advances in environmental research
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• v.4 no.3
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• pp.155-172
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• 2015

In this study, a complete set of recirculating cooling water system and the required instruments were built in a semi-industrial-scale and a 50 g/h ozone generation plant and a chlorine system were designed for cooling water treatment. Both chlorination and ozonation treatment methods were studied and the results were analyzed during two 45-days periods. The concentrations of ozone and chlorine in recirculating water were constant at 0.1 mg/lit and 0.6 mg/lit, respectively. In ozone treatment, by increasing the concentration cycle to 33%, the total water consumption decreased by 26% while 11.5% higher energy efficiency achieved thanks to a better elimination of bio-films. In case of Carbon Steel, the corrosion rate reached to 0.012 mm/yr and 0.025 mm/yr for the ozonation and chlorination processes, respectively. Furthermore, consumptions of the anti-corrosion and anti-sedimentation materials in the ozone cooling water treatment were reduced about 60% without using any oxidant and non-oxidant biocides. No significant changes in sediment load were seen in ozonation compared to chlorination. The Chemical Oxygen Demand of the blow-down in ozonation method decreased to one-sixth of that in the chlorination method. Moreover, the soluble iron and water turbidity in the ozonation method were reduced by 97.5% and 70%, respectively. Although no anaerobic bacteria were seen in the cooling water at the proper concentration range of ozone and chlorine, the aerobic bacteria in chlorine and ozone treatment methods were 900 and 200 CFU/ml, respectively. The results showed that the payback time for the ozone treatment is about 2.6 years.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2664-2671
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• 2012

This study aimed to investigate the relationship between physical characteristics and walking ability in the elderly population. Subjects were 77 elderly (38 men and 39 women) who are capable of walking independently with and without walking aids. Correlation and stepwise multiple linear regression analyses were used to analyze the relationship between physical characteristics (age, gender, height, weight, body mass index, muscle mass, waist/hip ratio, heart rate, vital capacity, flexibility, maximum oxygen consumption, one-leg standing time, and strength of knee flexor and extensor) and walking velocity of subjects. Age, height, vital capacity, one-leg standing time, and strength of knee flexor and extensor showed significant correlations with walking velocity of subjects (p<.05). Further, the strength of knee flexor explained 27% of the variance, and up to 32% of the walking velocity could be explained when the strength of knee extensor were added to the model. The findings suggest that walking velocity of elderly depends on the strength of lower limb's strength and a variety of physical characteristics.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.25-30
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• 2009

The present study deals with numerical investigation for smoke behavior in rescue station by using the commercial CFD code (FLUENT Ver 6.3). With the use of the MVHS(Modify Volumetric Heat Source) model modified from the original VHS(Volumetric Heat Source) model, a 10 MW mode was adopted for simulation and the MVHS model can describe the generation of product and the oxygen consumption at the stoichiometric state. In addition, the present simulation includes the species conservation equations for the materialization of heat source and the estimation of smoke movement. From the results, the smoke flows are moving along the ceiling because of thermal buoyancy force and as time goes, the smoke gradually moves downward at the vicinity of the entrance. Moreover, without using ventilation, it is found that the smoke flows no longer spread across the cross-passages because the pressure in the non-accident tunnel is higher than that in the accident tunnel.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2537-2543
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• 2011

A self-assembled Al-bridged diiminopyridine-based ligand (3) was synthesized and characterized by FT-IR, ESI-MS and NMR spectroscopy. Electron spectral titrations were performed to confirm the formation of a novel trinuclear bis(imino)pyridyl iron(II) complex (4) upon addition of $FeCl_2$ into Al-bridged ligand 3 in methanol solution. Simultaneously, a typical bis(imino)pyridine-iron(II) complex (2) was synthesized and fully characterized. The X-ray crystal study of the iron(II) complex 2 disclosed a five-coordinate, distorted square-pyramidal structure with the tridentate N^N^N ligand and chlorides. The optimal molecular structure of 4 was obtained by means of molecular mechanics, which showed that each iron atom in the complex 4 is surrounded by two chlorides, a tridentate N^N^N ligand and one oxygen atom, supporting considerations about the possibility of six-coordinate geometry from MMAO or the ethylene access. A comparison of 4 with the reference 2 revealed a remarkable decrease of the catalytic activity and MMAO consumption (activity up to $0.41{\times}10^3\;kg\;{mol_{Fe}}^{-1}h^{-1}bar^{-1}$, Al/Fe = 650 for 4 and $7.02{\times}10^3\;kg\;{mol_{Fe}}^{-1}h^{-1}bar^{-1}$, Al/Fe = 1600 for 2).

• Journal of Life Science
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• v.20 no.8
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• pp.1159-1165
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• 2010

Indirect calorimetry is the measurement of the amount of heat generated in an oxidation reaction by determining the intake or consumption of oxygen or by measuring the amount of carbon dioxide or nitrogen released and translating these quantities into a heat equivalent. In the last 20 years there has been significant development in both laboratory and computerized metabolic systems used in indirect calorimetry. In addition, there has been increased use of breath-by-breath EGAIC. Several researchers have suggested that breath-by-breath analysis, because of their practicality, could fulfill this need for a valid and reliable expired gas analysis indirect calorimetry instrument. It was hoped this investigation would determine the best validation for a precise measurement of breath-by-breath expired gas analysis indirect calorimetry. The problem with the available research is that few studies have examined the validity and reliability of all these different systems for breath-by-breath expired gas analysis indirect calorimetry. Therefore, there is a need to find out the most valid, reliable, and precise measurement of the breath-by-breath expired gas analysis indirect calorimetry.

• Journal of fish pathology
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• v.25 no.1
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• pp.47-58
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• 2012

Behavioral and physiological responses of juvenile red seabream (Pagrus major) to different concentrations of ethanol were investigated. No swimming and no reaction to touching by a wooden stick was observed at 0.6% ethanol group in behavioral response, and survival rate was 100% after 5 hours of treatment. Red blood cell count, hematocrit and hemoglobin levels in plasma were not significantly different among all groups. AST activities in plasma significantly decreased as ethanol concentration increased. On the contrary, ALT activities in plasma significantly increased as ethanol concentration increased. Cortisol level in plasma was the lowest in 0.6% ethanol group. Glucose levels in plasma increased significantly when ethanol concentration increased more than 0.4%. Oxygen consumption of fish in 0.6% ethanol seawater was constantly lower than that of fish in control seawater from 2 hours after the exposure to ethanol seawater until the end of experiment.

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.43-50
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• 2001

The effects of cardiac ischemia-reperfusion and $\beta$-adrenergic stimulation on metabolic function and energetics were investigated in Lan gendorff-perfused spontaneously hypertensive rat (SHR) hearts. Sarcoplasmic reticulum {TEX}$Ca^{2+}${/TEX}-dependent ATPase and cardiac lactate dehydrogenase (LDH) are additionally studied. The perfusion medium (1.0 mM {TEX}$Ca^{2+}${/TEX}) contained 5 mM glucose(+5 U/L insulin) and 2 mM pyruvate as substrates. Global ischemia was induced by reducing perfusion pressure of 100 to 40 cm {TEX}$H_{2}${/TEX}O, followed by 20 min reperfusin. Isoproterenol (ISO, 1$\mu$M) was infused for 10 min. Coronary vascular resistance and myocardial oxygen consumption ({TEX}$MVO_{2}${/TEX}) of SHR were increased in parallel with enhanced venous lactate during ischemia and reperfusion compared to those of Sprague Dawley (SD) hearts. Although ischemia-induced increase in venous lactate and combined adenosine plus inosine was abolished, coronary vasodilation produced in SD during reperfusion. In SHR, depressed reactive hyperemia was associated with a fall in cardiac ATP and CrP/Pi ratio and a rise in intracellular lactate/Pyruvate ratio. On the other hand, ISO produced coronary functional hyperemia and an increase in {TEX}$MVO_{2}${/TEX}. However, these responses were less than those in SHR hearts. The ATPase activity of SHR was attenuated in free {TEX}$Ca^{2+}${/TEX} concentrations used under basal condition and with ISO compared to that of SD. Venous lactate output and cardiac LDH activity were augmented in SHR as influenced by ISO. These results demonstrate that coronary reactive and functional hyperemia was dpressed in SHR, which cold be explained by alterations in the cytosolic phosphorylation potential and the cytosolic redox state manipulated by LDH, and by abnormal free calcium handling.

• Physical Therapy Korea
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• v.19 no.1
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• pp.56-65
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• 2012

This study examines the effects of a rehabilitation program on quality of life (QOL), cardiopulmonary function and fatigue during radiotherapy for breast cancer patients. The program includes aerobic exercise, stretching and strengthening exercises. Sixty-five women participated in this study and they were asked to perform supervised exercises that last for 60 minutes five times a week for six weeks. The European organization for research and treatment of cancer-cancer (EORTC QLQ-C30) and the breast (EORTC QLQ-BR23), predicted maximal volume of oxygen consumption ($VO_{2max}$) and fatigue severity scale (FSS) were assessed before and after the rehabilitation program. The 60-minute program consisted of a 10-minute warm-up, 30-minute of aerobic exercises, and 15-minute of strengthening exercises, followed by a five-minute cool-down. Heart rates were monitored throughout the exercise class to ensure that patients were exercising at the target heart rate of 40~75% of the age-adjusted heart rate maximum. There were statistically significant differences in the changes of physical function and cancer related symptoms in the EORTC QLQ-C30 and EORTC QLQ-BR23 (p<.05). There was a statistically significant improvement in the predicted $VO_{2max}$ (p<.05), although there were no significant differences in the FSS (p>.05). The results of our study suggest that a supervised rehabilitation program may benefit the physical aspects and QOL of patients receiving radiotherapy for breast cancer.

• The Korean Journal of Community Living Science
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• v.27 no.3
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• pp.419-435
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• 2016

The purpose of the present study was to suggest the design requirements for Korean naval duty uniforms by evaluating the physiological and psychological comfort while wearing the uniforms. Two sets of wear trials were conducted with summer uniforms(eight young males) and winter uniforms(seven other young males). The summer wear trial consisted of 10-min rest, 60-min exercise, and 10-min recovery at an air temperature($T_{air} $) of $33^{\circ}C$ and 62%RH, followed by 10-min recovery at a $T_{air} $ of $23^{\circ}C$ and 64%RH(total 90 min). The winter wear trial consisted of 20-min rest at $T_{air} $ $20^{\circ}C$ and 55%RH, 25-min rest, 30-min exercise, and 35-min recovery at a $T_{air} $ of 0oC and 43%RH(total 110 min). Rectal and seven skin temperatures, clothing microclimate, heart rate, oxygen consumption, total sweat rate, and subjective perceptions were measured during the wear trials. By evaluating the experimental results from the wear trials, we extracted the following psycho-physiological design requirements to improve the current Korean naval uniforms: (1) It is important to maintain the skin temperatures within their comfort range, which depends on the body region (higher than $30^{\circ}C$ in winter, but less than $35^{\circ}C$ in summer). (2) In summer, the feet should be protected from the high heat of the ship floor surface. (3) In summer, sweat from the back should be sufficiently absorbed and allowed to dry quickly.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.sup1
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• pp.83-92
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• 2008

Helicobacter pylori is the causative agent of chronic gastritis and has a role in the pathogenesis of peptic ulcer diseases, and gastric cancer. There have been reports suggesting a close link between these gastroduodenal disorders and a state of vitamin C deficiency. In this paper, the past, present and future perspectives on H. pylori infection and vitamin C will be discussed under the following view points. Since the ecological niche of H. pylori is the mucus layer and intercellular junctions of the gastric epithelium, the various kinds of host inflammatory cells motivated by the local and systemic immune responses cannot eliminate the microorganisms. When the invading foreign body is not removed, despite full activation of defense mechanisms, adverse consequences of the immune responses develop on the host gastric mucosa. The reasons for the body vitamin C depletion could be explained as follows; 1) the increased vitamin C consumption by increased oxygen free radical production through the prolonged hypersensitivity reactions in the gastric mucosa, 2) the increased vitamin C oxidation by the nitrite which is formed from nitrate reduction by the intragastric bacteria proliferated in the hypochlorhydric gastric cavity, 3) the strong ${\gamma}$-glutamyltranspeptidase activity of H. pylori which depletes the glutathiones in gastric mucosa. Depletion of glutathiones in the stomach favors irreversible oxidative destruction of ascorbic acid. Both persistent inflammatory burdens in the stomach by H. pylori and resultant vitamin C depletions synergistically and uninhibitedly might aggravate the hypothetical sequence of gastric carcinogenesis: atrophic gastritis${\rightarrow}$intestinal metaplasia${\rightarrow}$dysplasia${\rightarrow}$gastric adenocarcinoma. High intake of vitamin C could reverse the hypothetical sequence of the gastric carcinogenesis via direct and indirect effects on H. pylori and host-parasite relationships.