• Journal of Life Science
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• v.21 no.1
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• pp.9-14
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• 2011

Perceived exertion involves detection and interpretation of sensations arising from the body during physical exercise. Physiological variables such as heart rate and oxygen consumption positively correlate with ratings of perceived exertion (RPE). It is unknown whether the accuracy of predicting exercise intensity from RPE differs between men and women. Therefore, it was examined whether men or women could predict relative exercise intensity, determined by oxygen consumption, more accurately from RPE. Ten male and ten female young adult subjects aged 25.1${\pm}$3.52 yr volunteered to participate. RPE were determined by the Borg 15-category scale, and a standard Bruce treadmill protocol was used to perform graded exercise testing. There was no significant difference in slope means between males and females (p=0.501). No significant difference was observed when plotting rates of perceived exertion (RPE) vs. percentage of $VO_2$ max. The relative maximal oxygen consumptions ($VO_{2max,\;}_{rel}$) were 52.36${\pm}$7.35 ml/kg/min for males and 41.44${\pm}$6.71 ml/kg/min for females, respectively and there was a significantly high difference between the two groups in the relative $VO_{2max}$, as well as figures of 4.05${\pm}$0.36 l/min for males and 2.53${\pm}$0.39 l/min for females in the absolute $VO_{2max}$ in this study. There were no significant differences in slope, y-intercept, and standard error of estimate (SEE) between males and females. No significant difference with RPE according to exercise intensity was found between males and females. However, RPE was a useful predictor of exercise intensity in independent genders.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.169-174
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• 2004

The NOx emission characteristics with oxygen enrichment in nonpremixed counterflow and coflow jet flame of $CH_4$ fuel have been investigated numerically. A small amount of nitrogen is included in oxygen-enriched combustion, in order to consider the inevitable $N_2$ contamination by air infiltration. The results show that the initial increase of NO with increasing oxygen enrichment is due to increasing temperature and residence time, while its subsequent decrease above 75% oxygen is due to decreasing the consumption rate of nitrogen. When oxygen addition exceeds 30%, Thermal NO gradually becomes the dominant production pathway and Prompt NO becomes negative pathway for net NO production rate. It is also seen that Thermal NO plays an important role in NO reduction when strain rate increase in oxygen-enriched combustion. Finally, the results of EINOx with oxygen enrichment in coflow jet flame show the similar profile with those of conterflow flame. It is confirmed that, with leakage of 1% nitrogen in the oxidizer stream, the corresponding EINOx is eight times of that emitted from regular $CH_4$/Air flame.

• Journal of Plant Biology
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• v.36 no.3
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• pp.259-266
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• 1993

In Tris-iso-butanol (TIB; Tris buffer pH 8.8 and 1% iso-butanol)-treated chloroplasts, oxygen evolving activity was more inhibited than Tris-treated chloroplasts, but restored highly by 2,6-dichlorophenol-indophenol (DCPIP) and photoreactivation. To understand the mechanism of this results of TIB in photosynthetic electron transport, system, oxygen consumption and evolution of PS I and PS II were measured and protein of the chloroplasts was analysed. In Tris- and TIB-treated chloroplasts, oxygen evolving activity was increased according to the light intensity. Under 48 W·m-2 light intensity, the oxygen evolving activity in both chloroplasts were similar but as the light intensity was increased, TIB-treated chloroplasts showed higher activity. Under 240 W·m-2 light intensity, TIB-treated chloroplasts showed about 25% higher oxygen evolving activity than Tris-treated chloroplasts. Oxygen evolving activity was increased after photoreactivation in both Tris-treated and TIB-treated chloroplasts. Addition of NH4Cl increased the activity in both chloroplasts but in TIB-treated chloroplasts the increase was 30% higher than that in Tris-treated chloroplasts. In PS I, oxygen evolving activity was not inhibited by both treatments whereas in PS II, significant difference was observed between two treatments. Addition of Mn2+ and Ca2+ enhanced oxygen evolution in both Tris- and TIB-treated chloroplasts. Though enhancement was higher in TIB-treated chloroplasts. No difference was observed n protein analysis of the two thylakoid membrane.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.269-270
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• 2002

Oxygen is a key substrate in animal cell metabolism and its consumption is thus a parameter of great interest for monitoring and control in animal cell culture bioreactor. The use of a gas-permeable membrane offered the possibility to provide the required quantity of oxygen into the culture. while avoiding problems of foaming or shear damage generally linked to sparging. For determining the optimum DO control strategy of this gas-permeable membrane aeration bioreactor, the oxygen transfer rate coefficient was measured with varying $N_2$ ratio in inlet air. The results showed that an increasing mass flow rate of nitrogen reduced the $K_La$ value. and 5% nitrogen in air did not result in any oxygen limitation.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.43-48
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• 1996

We investigated the energistics of the physiological heart model by comparing predictive indexes of the myocardial oxygen consumption (MOC), such as tension-time index (R), tension-time or force-time inteual (FTI), rate-pressure product (RPP), pressure-work index, and systolic pressure-volume area (PVA) when using the electro-hydraulic left ventricular device (LVAD). We developed the model of LVAD incorporated the closed-loop cardiovascular system with a baroreceptor which can control heart rate and time-varying elastance of left and right ventricles. On considering the benefit of the LVAD, the effects of various operation modes, especially timing of assistance, were evaluated using this coupled computer model. Overall results of the computer simulation shows that our LVAD can unload the ischemic (less contractile) heart by decreasing the MU and increasing coronary flow. Because the pump ejection at the end diastolic phase of the natural heart may increase the afterload of the left ventricle, the control scheme of our LVAD must prohibit ejecting at this time. Since the increment of coronary flow is proportional to the peak aortic pressure after ventricle contraction, the LVAD must eject immediately following the closure of the aortic valve to increase oxygen availability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.126-130
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• 2004

This study is to identify the physiological traits of submergence-tolerant varieties of rice plants (Oryza sativa L.) in Yeongnam area, southeastern part of Korea, where the reduction of rice yield due to submergence is remarkably severe. In the present study, two tolerant varieties of rice plants were selected from over 30 rice varieties grown in under a 10-day period. The tolerant varieties selected from a submerged paddy field. As a control, one intolerant variety of rice plant was chosen. Of the tolerant variety Samgangbyeo, rather than Haepyungbyeo, had a lower dissolved oxygen consumption and maintained a higher dry weight than the intolerant variety. The leaf photosynthetic rates (LPS) of the two tolerant varieties were significantly higher than that of the intolerant-variety after four days of submergence treatment. These results indicate that lower dissolved oxygen consumption in a limited pool is prevented by ethylene formation in the tolerant varieties, which may be a mechanism of submergence tolerance.

• Journal of Life Science
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• v.9 no.1
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• pp.92-98
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• 1999

This study was aimed to evaluate the effect of saengmaeksan on the recovery of exercise induced fatigue. In this experiment, white rats were divided into 2 groups; control group and Saengmaeksan treated group. The results were as follows: 1. Oxygen consumption was significantly decreased in Saengmaeksan treated group than in control. 2. Serum lactate levels were significantly decreased in Saengmaeksan treated group than in control. 3. Serum LDH activities were significantly decreased in Saengmaeksan treated group than in control. 4. Serum triglyceride levels were significantly increased in Saengmaeksan treated group than in control. 5. Serum glucose levels were significantly increased in Saengmaeksan treated group than in control. 6. Serum FFA levels were significantly decreased in Saengmaeksan treated group than in control. According to the results, saengmaeksan showed remakable effects in the recovery of exercise induced fatigue.

• Journal of Ginseng Research
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• v.24 no.2
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• pp.83-88
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• 2000

The seasonal variation in the activity of sucrose synthase, ADP-glucose pyrophosphorylase and UDP-glucose pyrophosphorylase in roots of Panax ginseng C.A.Meyer have been studied. It was revealed that sucrose synthase and ADP-glucose pyrophosphorylase are adaptive enzymes and can serve as markers of sink strength, while UDP-glucose pyrophosphorylase is the maintenance enzyme. The average day temperature exceeded 24。C appeared to cause the disturbance in refilling process, affecting the starch synthesis. Study on the dependence of oxygen consumption in stele tissue with temperature revealed the sharp accelerating of this process after 24。C.

• KSBB Journal
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• v.8 no.4
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• pp.364-369
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• 1993

The biodegradability of some anionic surfactants were investigated using biological oxygen consumption measurement at different temperatures. As test surfactants, soap, alkyl sulfate (AS), alpha olefin sulfonate (AOS), alkyl polyoxyethylene sulfate (AES), linear alkylbezene sulfonate(LAS), microbial surfactants such as sophorose lipid (sopholipid) and spiculisporic acid (S-acid), were used. The test solution were incubated at $5^{\circ}C$, $18^{\circ}C$ and $32^{\circ}C$, respectively. The comparative rates of biodegradation were in accordance with the results obtained from the surface tension measurement and methylene blue method. The results of comparative blodegradabilities of the surfactants were as follows; soap, AS>AES>AOS>LAS at $18^{\circ}C$ and $32^{\circ}C$. However, at$ 5^{\circ}C$, the biodegradation rate of soap was better than other surfactants. Considering the actual environment of the river, it was concluded that the biological oxygen consumption rate method at lower temperature was more practical than the current method such as methylene blue assay with adapted shaking flask culture at $25^{\circ}C$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.30-34
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• 1988

In roastal fish farms the farmers, especialy engaging in dealing with the floating cage culture, going to know about relationships between holding capacity and water quality in cage. Some of water quality managers and specialists studing physiological ecology understand that the key of water quality management concerned fish farming is budget of dissolved oxygen. This paper deals with oxygen budget in floating cage of the yellow tail farms at southern coastal area in Korea. The sampling station is located at Konli-Do fish farm near Chungmu, and the data is collected for 24 hours from 3:00 p.m. 8th September 1987. In result, the needed oxygen coming after the consumption by the rearing fish had been supplied with the tide current exchange, the sum of oxygen produced by phytoplankton photosynthesis and diffused from atmosphere are no more that $43\%$ for the needs of sea water consumption included respiration of planktons and decomposition of organic matters. The optimum holding capacity of cage is possible to compute with the calculation of minimum diurnal water exchange rate $[Qin{\cdot}V^{-1}\;(C-\bar{c})]$ through net mesh of cage.