• 한국수산과학회지
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• 제33권2호
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• pp.110-114
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• 2000

다대포 연안에 서식하는 곤쟁이를 대상으로 수온 $20{\circ}C$에서 염분 $20{\%}_{\circ}$ 및 $32{\%_{\circ}}$에서의 용존산소 농도별 사망률, 산소소비율 및 암모니아 배설률의 변화를 알아 보았다. 염분 $20{\%_{\circ}}$ 및 $32{\%_{\circ}}$에서 곤쟁이의 $96hr-LC_(50)은 각각 2.20mg DO/l와 1.60mg DO/l였으며, 용존산소 농도 0.6mg DO/l에서 24시간내 모두 사망하였다. 용존산소 농도에 따른 곤쟁이의 산소소비율 및 질소배설률의 변화는 두 염분구에서 산소소비율은 용존산소 농도의 증가에 따라 증가를 보인 반면 암모니아 배설률은 용존산소 1 mg DO/l에서 가장 높게 나타났으며, 용존산소의 증가에 따라 감소하였다. 염분과 각 용존산소 농도별 96시간 동안 노출한 곤쟁이의 O:N비는 염분 $20{\%_{\circ}}$에서 용존산소 농도 $1.0{\~}2.0mg DO/l$에서는 10 이하였으며, $32{\%_{\circ}}$에서는 용존산소 농도 1.0mg DO/l에서 4.4로서 저농도 산소의 상태에서 생존을 위한 에너지 기질로서 단백질을 이용하는 것으로 추정되었다.

• 한국수산과학회지
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• 제48권5호
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• pp.712-718
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• 2015

The effects of salinity on survival, oxygen consumption, and hematological response of greenling Hexagrammos otakii, mean body weight 147.1±3.8 g, were investigated under salinity conditions of 33.4 (control), 33.1, 32.8, 32.2, 31.0, 28.7, 23.9, 14.5, and 3.8 psu, to evaluate physiological effects in relation to changes in salinity. The survival and hematological responses of fish were measured at each salinity after 96- and 24-h exposures. The oxygen consumption rate (OCR) of fish was measured in triplicate under conditions of stepwise salinity exposure (33.4→33.1→32.8→32.2→31.0→28.7→23.9→14.5→3.8 psu) with an interval of 24 h at each salinity, using a continuous flow-through respirometer. No fish mortality was observed in the range of 33.4 to 14.5 psu, but the survival rate was reduced to 53.3% at 3.8 psu after 96 h of exposure. The OCRs did not significantly differ in the range between 33.4 to 28.7 psu (P>0.05), but significantly increased at 23.9 and 14.5 psu, and then dramatically decreased at 3.8 psu compared to the control (P<0.05). Hematological variables, such as glucose, glutamic pyruvic transaminase (GPT), hematocrit, and Na⁺, were affected by reduced salinity. This result may be applicable for habitat and culture management of greenlings.

• Ocean and Polar Research
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• 제36권2호
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• pp.135-143
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• 2014

The effect of salinity on the survival, oxygen consumption and blood physiology of Korean rockfish Sebastes schlegelii (body weight $97.4{\pm}1.7g$, $mean{\pm}SD$) was investigated at nine different salinities of 33.4 (control), 33.1, 32.8, 32.2, 31.0, 28.7, 23.9, 14.5 and 3.8 psu, respectively. Survival and blood physiology were measured at each salinity in two separate trials of 96 and 24 hr duration, respectively. Oxygen consumption rate (OCR) was determined at stepwise salinity exposure ($33.4{\rightarrow}33.1{\rightarrow}32.8{\rightarrow}32.2{\rightarrow}31.0{\rightarrow}28.7{\rightarrow}23.9{\rightarrow}14.5{\rightarrow}3.8$ psu) with an interval of 24 hr for each salinity. No death of fishes were observed in the range of 33.4 to 14.5 psu, but the survival rate was reduced to 26.7% at 3.8 psu after 96 hr. The OCRs were not significantly different in the range 33.4 to 28.7 psu (p > 0.05), but significantly increased until 14.5 psu and then drastically decreased at 3.8 psu compared to the control (p < 0.05). The concentrations of plasma $Na^+$ and $Cl^-$ were significantly lower in fish exposed at 3.8 psu compared to the control (p < 0.05). The results of this study provide evidence that S. schlegelii exposed to concentrations below 23.9 psu show significant physiological responses to tolerate salinity changes under the experimental conditions we established.

• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.560-564
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• 2013

${\small{D}}$-Ribose is a value-added five-carbon sugar used for riboflavin production. To investigate the effects of oxygen supply and mixed sugar concentration on microbial production of ${\small{D}}$-ribose, a transketolase-deficient Bacillus subtilis SPK1 was cultured batch-wise using xylose and glucose. A change of agitation speed from 300 rpm to 600 rpm at 1 vvm of air supply increased both the xylose consumption rate and ${\small{D}}$-ribose production rate. Because the sum of the specific consumption rates for xylose and glucose was similar at all agitation speeds, metabolic preferences between xylose and glucose might depend on oxygen supply. Although B. subtilis SPK1 can take up xylose and glucose by the active transport mechanism, a high initial concentration of xylose and glucose was not beneficial for high ${\small{D}}$-ribose production.

• 한국안전학회지
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• 제31권4호
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• pp.55-63
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• 2016

A dust explosion is a phenomenon of strong blast wave propagation involving destruction which results from dust pyrolysis and rapid oxidation in a confined space. There has been some research done to find individual explosion characteristics and common physical laws for various dust types. However, there has been insufficient number of studies related to the heat of combustion of materials and the oxygen consumption energy about materials in respect of dust explosion characteristics. The present study focuses on the relationship between dust explosion characteristics of wood dust samples and oxygen consumption energy. Since it is difficult to estimate the weight of suspended dust participating in explosions in dust explosion and mixtures are in fuel-rich conditions concentrations with equivalent ratios exceeding 1, methods for estimating explosion overpressure by applying oxygen consumption energy based on unit volume air at standard atmospheric pressure and temperature are proposed. In this study an oxygen consumption energy model for dust explosion is developed, and by applying this model to TNT equivalent model, initial explosion efficiency was calculated by comparing the results of standardized dust explosion experiments.

• 수산해양교육연구
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• 제26권1호
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• pp.214-222
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• 2014

Hagfish Eptatretus burgeri is classified as a agnathans and has many different physiological properties compared with vertebrates. In this study, we examined effects of water temperature and salinity on blood properties and oxygen consumption in hagfish. In the experiment of water temperature change, hematocrit (Ht), red blood cell (RBC) and glucose of hagfish blood revealed the lowest values at $15^{\circ}C$. Oxygen consumption of hagfish had significantly increased with rising water temperature, and the increasing rate was twice as much when the temperature was manipulated every $5^{\circ}C$. Also, oxygen consumption during the night time (a short photoperiod) was significantly higher than that of the daytime. Q10 level was 3.50 in the light period and 3.92 in the dark period. No significant change in plasma glucose level was showned in changing salinity from 30 psu to 22 psu, while it had rapidly increased at 20 psu ($13.7{\pm}4.0mg/dL$) and thereafter all hagfish were dead at 18 psu. However, osmolarity, $Na^+$, $K^+$ and $Cl^-$ levels had significantly decreased when salinity decreased. This results are expected to develop the artificial rearing techniques of natural hagfish.

• The Korean Journal of Physiology
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• 제6권2호
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• pp.9-17
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• 1972

This experiment was carried out to investigate systematically how the aerobic metabolic capacity of renal tissue reduced by the effects of a period of induced ischemia. Aerobic metabolic studies were performed on homogenates of cortex and medulla of rabbits. Ischemia was induced by occluding the renal vein or renal artery of the left kidney for an hour. The right kidney used as a paired control. Aerobic metabolism was asesssed by measuring the oxygen consumption using the Warburg's manometric apparatus. The results are summarized as follows: 1. One hour of occlusive ischemia does not increase in the kidney weight in the renal arterial occlusion but increase in the renal venous occlusion. 2. Occlusion of either the renal vein or renal artery for an hour did not reduce to any significant degree the level of endogenous substrate in cortical homogenates as measured the rates of $0_2$ consumption. 3. A significant reduction in the rate of $C_2$ consumption was noted in the medullary homogenates of renal venous occluded kidneys while renal arterial occlusion had less of an effect. 4. The capaciy of homogenates for aerobic metabolism is not reduced by acute ischemia, because of the higher rate of oxygen consumption induced by exogenous glucose in renal vein occlusion. 5. The oxygen consumption of medullary homogenate more decreased to acute ischemia than cortical homogenates. The results of this investigation suggest that one hour circulatory stasis does not reduce major potential capacity of renal cortical tissue at the subcellular level to produce energy. In contrast, the aerobic metabolism of medullary tissue is reduced by renal ischemia. Further, both cortex and medulla appear to be more sensitive to ischemia induced by renal venous occlusion than by renal arterial occlusion.

• 한국수산과학회지
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• 제30권5호
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• pp.874-881
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• 1997

곤쟁이 Neomysis awatschensis의 치하와 성체에 대한 중금속의 급성독성 수준과 아치사 농도에서 생존, 성장, 탈피 및 산소소비에 미치는 cadmium, copper 및 chromium의 독성을 검토하였다. Cadmium, copper 및 chromium에 대한 곤쟁이 성체의 $96hr-LC_{50}$은 각각 20.2, 11.3, $670.4\;{\mu}g/\ell$, 치하에서는 각각 3.4, 1.9 및 $49.4\;{\mu}g/\ell$이었다. 성체와 치하의 $96hr-LC_{50}$을 기준으로 중금속의 독성은 copper>cadmium>chromium 순이었다. 치하를 각 중금속의 아치사 농도에 40일간 노출시키면서 생존, 성장 및 탈피에 미치는 영향을 조사한 결과, 생존율은 cadmium이 $\geq1.0\;{\mu}g/\ell,\;copper\geq0.6\;{\mu}/\ell$에서 유의한 감소를 보였다. 성장률은 cadmium $2.0\;{\mu}g/\ell$와 copper $\geq1.2\;{\mu}g/\ell$의 농도에서 유의한 감소가 관찰되었으나 탈피기간에는 영향이 없었다. 산소소비량은 중금속 농도가 높을수록 감소하였고, 대조구의 산소소비량을 기준으로 하여 중금속 농도에 따른 산소 소비량은 cadmium과 copper는 $5\;{\mu}g/\ell$ chromium은 $10\;{\mu}g/\ell$ 농도에서 약 $50\%$ 감소하였다. 이상의 결과로부터 하구역에 cadmium이 $\geq1.0\;{\mu}g/\ell$, copper가 $\geq0.6\;{\mu}g/\ell$ 농도가 존재할 경우 곤쟁이의 분포와 개체군의 크기에는 많은 영향을 미칠 것으로 사료된다.

• 한국수산과학회지
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• 제33권5호
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• pp.408-412
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• 2000

염분에 대한 날개망둑의 내성범위를 파악하기 위한 일환으로 이들의 생존, 성장 및 대사에 미치는 염분의 영향을 40일간 사육 실험을 통하여 검토하였다. 날개망둑의 생존율은 염분 $10.1{\%_{\circ}}$ 이상에서 $90{\%}$ 이상을 나타냈으나, 염분 $6.7{\%_{\circ}}$ 이하에서는 유의한 감소를 나타냈고, 담수에서는 40일째 $5{\%}$의 생존율을 보였다. 성장은 $20.2{\~}33.6{\%_{\circ}}$의 염분 범위에서 유사한 체장, 체중의 증가 및 일일성장률을 나타냈으나, 염분 $10.1{\%_{\circ}}$ 이하에서 유의한 감소가 관찰되었다. 산소소비는 염분 $20.2{\~}33.6{\%_{\circ}}$에서 유사하게 나타났으나, 염분 $13.4{\%{\circ}}$ 이하에서 염분이 감소함에 따라 감소하는 경향을 보여 염분 13.4, 10.1, 6.7 및 $3.4{\%_{\circ}}$에서 각각 15.8, 19.3, 18.6 및 $24.1{\%}$의 유의한 감소를 보였고, 담수에는 $28.2{\%}$의 감소가 관찰되었다. 이러한 결과는 낮은 염분에서 생존, 성장 및 산소소비율이 낮다는 것을 지적하고 있으며, 염분의 농도차이가 연안지역이나 기수지역에서 자연사망율에 잠재적으로 영향을 미칠 수 있다는 것을 암시한다.

• 한국동물학회지
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• 제29권3호
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• pp.201-207
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• 1986

소금쟁이 (Gerris paludum insuralis)성체의 호흡률을 $25^\\circ C, 30^\\circ C, 35^\\circ C$ 및 $40^\\circ C$에서 암, 수별로 각각 1시간동안 매 5분간격으로 산소소비율을 측정하여 다음과 같은 결론을 얻었다. (1) $30^\\circ C$에서는 시간경과에 따른 산소소비량의 변화가 다른 온도군에 비해 매우 적었으며, 첫 5분간과 마지막 5분간의 양이 거의 비슷하여 생활적온으로 판단되며, 그 외의 온도에서는 시간경과에 따라 단위시간당 산소소비량은 주기적인 감소상을 나타내었다. (2) 산소소비율은 대체로 수컷이 암컷보다 많았다. (3) 산소소비량은 $25^\\circ C, 30^\\circ C, 35^\\circ C$ 및 $40^\\circ C$에서 각각 0.42, 0.49, 0.79 및 1.11 $\\mu$l/mg/hr로서 온도가 높아짐에 따라 증가하였다. (4) $Q_10$은 수컷에서는 $25^\\circ C \\sim 35^\\circ C$의 온도간격에서 높았고, 암컷은 $30^\\circ C \\sim 40^\\circ C$의 온도간격에서 높았다. 평균 $Q_10$은 2.12였다. (5) 생체량 10 mg, 건조중량 5 mg이상에서는 체중이 높을수록 산소소비량은 감소하였다. (6) 호흡정지고온과 호흡정지저온은 각각 $48.31^\\circ C$와 $17.68^\\circ C$였다. (7) $30^\\circ C$를 제외한 세 온도군에서 호흡이 정지되는 시간은 약 110분 후로 추정되었다.