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Comparison of Olfactory Sensibility With/Without Consideration of Individual Olfactory Threshold (피험자의 후각 역치 고려 유무에 따른 후각 감성 비교)

  • Seo, Han-Seok;Jeon, Kwang-Jin;Kwon, Jin-Hwan;Hwang, In-Kyeong;Kang, Jin-Kyu;Min, Byung-Chan
    • Science of Emotion and Sensibility
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    • v.10 no.2
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    • pp.199-208
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    • 2007
  • The olfactory function of subjects could be different due to various factors such as aging, and such discrepancies influence on the olfactory sensibility. Therefore, the objectives of this study was to investigate changes of olfactory sensibility characteristics and structure in relation to the consideration of olfactory threshold of subject. Stimulants of this study were five standard odor samples of T&T olfactometer, and thirty undergraduates over than 19 years old were tested twice during this study In experiment 1, subjects were given to odor samples which were controlled on the basis of individual olfactory threshold. Whereas, subjects were provided with uncontrolled odor samples which had the same concentration(+1) in experiment 2. Olfactory sensibility characteristics were significantly different with presentation types of odor samples, and these gaps were more higher on condition that the preference of odor sample was not distinct. Moreover, such differences affected the olfactory sensibility structure, and 'esthetic sense', 'intensity', and 'activity' were common factors, but 'friendship' of experiment 1 and 'weight' of experiment 2 were unique factors. In conclusion, the olfactory sensibility characteristics and structure could be different with consideration of olfactory threshold of subject. Overall, this study suggest that the olfactory function and the presentation method of odor sample be regarded as principal consideration factors in the olfactory sensibility evaluation.

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A Study of Synthesis and Biological Function on DL-1-Aminoethylphosphonic Acid (DL-1-Aminoethylphosphonic acid의 생물학적(生物學的) 기능연구(機能硏究))

  • Kim, Sook-He;Cho, Jung-Nam;Kim, Yong-Joon
    • Journal of Nutrition and Health
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    • v.2 no.4
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    • pp.173-181
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    • 1969
  • Since 1959 ${\beta}-aminoethylphosphonic$ acid was discovered in the living organism, the biosynthesis and biological functions of aminophosphonic acids have been extensively studied. The author designed and carried out this study for 14 weeks to find out the metabolic function of Ethylaminophosphonic acid (AEP) and it's utilization in the living body. Sixty rats, thirty males and thirty females aged $40{\pm}5$ days were divided into two parts, one for alanine supplemented as control group and the other for AEP as experimental group to compare metabolic pathway of ordinary amino acid with that of AEP. Both alamine and AEP group were divived into two subgroups according to the level of supplements, 0.1% and 0.2% of the diet. The major components of the diet in this study were composed of 20% casein, 72% Sugar, 4% fat, 4% salt Mixture, and all kind of Uitamins in adeguate amount. For comparision of biological values between experimental and control group in terms of body weight, uninary nitrogen, creatinine excretion and final orgam weight, there were no statically significant difference in these respects. This meant AEP could be utilized in the body as much as alanine could. Urinary phosphorus excretion was determined by developing the blue color to read on the Spectronic 20. Statistically insignificance in the urinary phosphorus excretion between experimental and control group was observed in spite of the supplementation of phosphorus of AEP for experimental group in the diet. The level of blood phosphorus was higher in experimental group than that in control group this result supported above result. In the analysis of fat and nitrogen contents in the liver, AEP group showed slightly higher than control in both respects. But it was noteworthy 0.2% AEP group in both sex were higher than 0.1% AEP in liver fat content. Histological examinal of internal organs liiver, lung, spleen, heart, kindey, adrenal and sex organs showed no changes in all groups included in this study. The group supplemented higher level of diet. by alanine 0.2% and AEP 0.2% stayed on less body weight gain and lower liver weight. This result could be interpreted that amino acid imbalanced condition was arose in the body.

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The Characteristic and Implication of the View of Object in Oriental Medicine (한의학적(韓醫學的) 대상관(對象觀)의 특징과 성격)

  • Lee, Choong-Yeol
    • The Journal of Korean Medicine
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    • v.16 no.1 s.29
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    • pp.505-530
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    • 1995
  • Recently some people in learned circles of oriental medicine raised a Question about a terminological problem, i.e., 'oriental medical'. This question was thought as an attempt to find out the identity of oriental medicine which exists among the various current medical knowledge systems. In spite of same object, human body, there are diverse medical knowledge systems which has different concepts and theories. This come from the difference of a view of object which defines the experiences of that. The knowledge system of oriental medicine was established by the view of object in oriental medicine which depended on the way of thinking as Yin and Yang. The view of object in oriental medicine has come out in the special cultural soil, namely, the oriental world. Because of this the view of object in oriental medicine cannot be seperated from the oriental world view. What distintive feature does the oriental world view have? It can be summarized as the holistic, dynamical and organic ideas of the world. The term 'oriental medical' is being used to emphasize the characteristic and the peculiarity of the oriental medicine among the various medical knowledge systems. Can the current so called scientific method accept this peculiar and special method of oriental medicine? The efforts of philosophers who had been stimulated by the awful scientific achivements and had tried to find out the unified method penetrating through all the empirical science by mobilizing the logic and mathematics has became out of date for the raise of a question about the inductive method. On the contrary, the theses of theory-laden observation was accepted widely and the relativism was accepted as a new established theory. But the relativism has its own problem. The relativism was founded upon the concept, the incommensurability, which Khun and Feyerabend had proposed. This concept was criticized strongly by some of philosophers because of its own self-refuting. The view of object in oriental medicine has a relative characteristic in the aspect of its urge that in accordance with the perspective a different medical knowledge system can be possible. But our possible choice is the moderate conceptual relativism. Therefore if the view of object in oriental medicine includes the relative aspect, there is the 'conceptual relativity' between the knowledge system of oriental medicine and the western medicine. This preview an important aspect for the standardization and modernizing research of oriental medicine by lending the knowledge of the western medicine. And when we choose the moderate conceptual relativism, it means that we do not support the extreme relativism, that is, 'anything goes'. The concept of truth and rationality cannot be abandoned, and it plays the role of the norm on the knowledge system of oriental medicine and other knowledge systems of medicine in a limited meaning. And the view of object in oriental medicine has an organic view about the human body and the characteristic which wants to interpret the phenomena of human body by using the holistic method. But the availability of this method will be evaluated by the achievements of oriental medicine. Finally what relationship does the theory of oriental medicine have with the world the theory is applied to? It is recognized that the theory of oriental medicine has the instrumental characteristic. But it can be thought the instrumentalism is different from the oriental medical standpoint in the aspect that the instrumentalism seperates the theoretical existence from the observational existence sharply. Because in the oriental thinking way there is no seperation between the mind of observer and the object and no conflict between the idealism and the realism like the western world. For this problem there must be a further study.

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Behaviour of the Soil Residues of the Acaricide-Insecticide, [$^{14}C$]Acrinathrin;II. Degradation in Soil (살비살충제 [$^{14}C$Acrinathrin 토양 잔류물의 행적 규명;II. 토양중 분해)

  • Lee, Jae-Koo;Kyung, Kee-Sung;Oh, Kyeong-Seok
    • Korean Journal of Environmental Agriculture
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    • v.14 no.2
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    • pp.202-212
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    • 1995
  • In order to elucidate the degrading characteristics of the pyrethroid acaricide-insecticide, acrinathrin in two different types of soils, Soil A(pH, 5.8; organic matter, 3.4%; C.E.C., 115 mmol(+)/kg soil; texture, sandy loam) and Soil B(pH, 5.7; organic matter, 2.0%; C.E.C., 71 mmol(+)/kg soil; texture, sandy loam), residualities of the non-labeled compound under the field and laboratory conditions, extractability with organic solvents and formation of non-extractable bound residues, and degradabilities of [$^{14}C$]acrinathrin as a function of aging temperature and aging period were investigated. The half lives of acrinathrin in Soil A treated once and twice were about 18 and 22 days and in Soil B about 13 and 15 days, respectively, in the field, whereas, in the laboratory, those in Soil A and B were about 36 and 18 days, respectively, suggesting that the compound would be non-persistent in the environment. The amounts of $^{14}CO_2$ evolved from [$^{14}C$]acrinathrin in Soil A and B during the aging period of 24 weeks were 81 and 62%, respectively, of the originally applied $^{14}C$ activity, and those of the non-extractable soil-bound residues of [$^{14}C$]acrinathrin were about 70% of the total $^{14}C$ activity remaining in both soils, increasing gradually with the aging period. Degradation of [$^{14}C$]acrinathrin in both soils increased with the aging temperature. Three degradation products of m/z 198(3-phenoxy benzaldehyde), m/z 214(3-phenoxybenzoic acid), and m/z 228(methyl 3-phenoxybenzoate) as well as an unknown were detected by autoradiography of acetone extracts of both soils treated with [$^{14}C$]acrinathrin and aged for 15, 30, 60, 90, 120, and 150 days, respectively, and the degradation pattern of acrinathrin was identical in both soils. Acrinathrin in soil turned out to be degraded to 3-phenoxybenzaldehyde cyanohydrin by hydrolytic cleavage of the ester linkage adjacent to the $^{14}C$ with a cyano group, the removal of hydrogen cyanide therefrom led to the formation of 3-phenoxybenzaldehyde as one of the major products, and the subsequent oxidation of the aldehyde to 3-phenoxybenzoic acid, followed by decarboxylation would lead to the evolution of $^{14}CO_2$.

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Effect of Preparation method and Fermentation Conditions on Microbiological Characteristics of Sikhae (어류를 이용한 식해의 제조 방법에 따른 미생물의 특성변화)

  • Kim, Young-Sook;Oh, Seung-Hee;Kim, Soon-Dong
    • Food Science and Preservation
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    • v.15 no.6
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    • pp.909-914
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    • 2008
  • This study investigated microbial populations and the sensory quality of sikhae including globefish (GLS), flounder (FLS), gastropods (GAS) and whelks (WHS) during storage at 4C for 16 d following fermentation at 10C for 4 d. General bacterial numbers increased to 102 in GLS and FLS, and to 1045 in WHS and GAS after the 20 d fermentation/storage period. Lactic acid bacteria increased to 108 log cycle in GLS and FLS after 10 d ripening time, and reached this level in GAS and WHS after 15 d and 20 d, respectively. After 20 days the number of lactic acid bacteria in each of the four samples was 108. There were 104105 yeast cells/g in each of the four samples after 20 d. The number of Leuconostoc increased to over 108 log cycle after 10 d in GLS and FLS, and 15 days in GAS for WHS the increase was to 107 log cycle. The pH values of GLS, FLS, GAS and WHS 4.42, 4.56, 4.31 and pH 4.26, respectively. The Sikhae acidity for all four samples ranged from 1.551.85%. From the sensory evaluation the overall acceptability was in the order of FLS > GLS > GAS > WHS.

Nitrogen and Phosphorus Uptake and Growth Kinetics of Microcystis aeruginosa Cultured under Chemostats (연속배양에서 Microcystis aeruginosa의 질소 인 흡수와 생장 특성)

  • Lee, Ok-Hee;Cho, Kyung-Je
    • Korean Journal of Ecology and Environment
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    • v.39 no.1 s.115
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    • pp.119-130
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    • 2006
  • As unialgal cultures to examine the growth kinetics of an algal species, Microcystis aeruginosa was grown in chemostats with nitrogen and phosphorus limitation. The nutrient concentrations of $NH_4\;^+\;and\;PO_4\;^{3-}$ to limit the growth of M, aeruginosa were approximately 200 ${\mu}M$ and 7 ${\mu}M$, respectively. Cell size of the algae decreased towards the $NH_4$-nitrogen limitation under a constant dilution rate, while it increased in the $PO_4$-limitaion. The cell quota of nitrogen under nitrogen-limited conditions was 6.1 ${\mu}mol$ mg $C^{-1}$ and, under nitrogen sufficient conditions, ranged from 9.5 ${\mu}mol$ mg $C^{-1}$ to 12.4 ${\mu}mol$ mg $C^{-1}$. In addition to the cell quota, the half-saturation constants for nitrogen uptake ($K_s$) and the growth rate (${\mu}_m$) was 36 ${\sim}$ 61 ${\mu}M$ and 0.28 ${\sim}$ 0.35 ${\mu}mol$ cell ${\cdot}$ $hr^{-1}$ to show high values in comparison with other algal species. As the limiting concentration, cell quota and uptake rate of M. aeruginosa were higher than those of any other species, the its nitrogen requirement would be great. In the other side, as the half saturation constant ($K_s$) for nitrogen uptake was higher, and the ratios ofmaximum uptake rate ($V_m$) and $K_s$ was relatively low, the species would have the low competitive ability in the low nitrogen concentration in the ambient water. However, the low concentration of nitrogen in the Nakdong River during the Microcystis outbreak would be the inevitable results of the algal blooms. In the lower Parts of the Nakdong River, the nutrient status was coupled with the growth kinetics of the blooming algae to have clear seasonal variations through a year.

Petrological Study on the Cretaceous Volcanic Rocks in the southwest Ryeongnam Massif: (1) the Mt. Moonyu volcanic mass, Seungju-gun (영남육괴 남서부에 분포하는 백악기 화산암류에 대한 암석학적 연구: (1) 승주군 문유산 화산암복합체)

  • Kim, Young-La;Koh, Jeong-Seon;Lee, Jeong-Hyun;Yun, Sung-Hyo
    • The Journal of the Petrological Society of Korea
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    • v.17 no.2
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    • pp.57-82
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    • 2008
  • The volcanic sequence of the late Cretaceous Moonyu volcanic mass which distributed in the southwestern part of Ryeongnam massif, can be divided into felsic pyroclastic rocks, andesite and andesitic pyroclastic rocks, rhyolite in ascending order. The earliest volcanic activity might commence with intermittent eruptions of felsic magma during deposition of volcaniclastic sediments. Explosive eruptions of felsic pyroclastic rocks began with ash-falls, to progressed through pumice-falls and transmitted with dacitic to rhyolitic ash-flows. Subsequent andesite and andesitic pyroclastic rocks were erupted and finally rhyolite was intruded as lava domes along the fractures near the center of volcanic mass. Petrochemical data show that these rocks are calc-alkaline series and have close petrotectonic affinities with subduction-related continental margin arc volcanic province. Major element compositions range from medium-K to high-K. Petrochemical variation within the volcanic sequence can be largely accounted for tractional crystallization processes with subordinate mixing. The most mafic rocks are basaltic andesite, but low MgO and Ni contents indicate they are fractionated by fractional crystallization from earlier primary mafic magma, which derived from less than 20% partial melting of ultramafic rocks in upper mantle wedge. Based on the stratigraphy, the early volcanic rocks are zoned from lower felsic to upper andesitic in composition. The compositional zonation of magma chamber from upper felsic to lower andesitic, is interpreted to have resulted from fractionation within the chamber and replenishment by an influx of new mafic magma from depth. Replenishment and mixing is based on observations of disequilibrium phenocrysts in volcanic rocks. REE patterns show slight enrichment of LREE with differentiation from andesite to rhyolite. Rhyolite in the final stage can be derived from calc-alkaline andesite magma by fractional crystallization, but it might have underwent crustal contamination during the fractional crystallization.

An Initial Study on the Reliability Assurance in PET/CT Standardized Uptake Values (PET/CT 에서 표준섭취계수(SUV)의 신뢰성 확보를 위한 초기연구)

  • Park, Hoon-Hee;Kim, Jung-Yul;Lee, Seung-Jae;Park, Min-Soo;NamKoong, Hyuk;Lim, Han-Sang;Oh, Ki-Baek;Kim, Jae-Sam;Lee, Chang-Ho;Jin, Gye-Hwan
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.3
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    • pp.31-42
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    • 2009
  • Purpose: As the number of domestic medical institutions installing PET/CT is increasing rapidly, the transfer of PET/CT images among medical institutions is also increasing. Thus, it is necessary to collect the comparative SUV data from several medical institutions' PET/CT systems through a phantom study which semi-quantitatively compares the SUV on one bed, the change scale of the SUV on the slices, and the time of measuring. The phantom study to find differences among the SUVs from various PET/CT offers the opportunity to obtain the reliability of the SUV in PET/CT images. Materials and Methods: Ten PET/CT systems from medical institutions in Korea were used. To obtain the accurate data, the study has been using the radiation detector of Korea Research Institute of Standards and Science to verify. The internal structures of NEMA $phantom^{TM}$ were removed and Six thousand milliliters of distilled water which has 1mCi of $^{18}F$-FDG put into the phantom. The water was properly integrated with $^{18}F$-FDG using magnetic stirrer. The images were acquired at 60, 70, 80, 90, 100, 110 and 120-minutes for 3 minute each. Two hundred square centimeters of region of interests were placed and analyzed. To confirm the usefulness, the correction-table came out from patients' data. Results: The coefficient of variability of the SUV from -11.0 to 9.90 % fell into the range of international standards(${\pm}10%$) along with the SUV on a bed, the change scale of the SUV on the slices, and the time of measuring, except one PET/CT system. Using the data of the differences among the SUVs, we came to withdraw the correction-table ranging from 0.803 to 1.246. The correction-table was confirmed its usefulness through Linear Regression Analysis which was applied to normal cases. Conclusions: Although studies have been made on the variation of the SUV, there is little attention on the standardization of the SUV. Based on this study of the quantitatively comparable data about the SUV accommodating the correction-table, it would help to have more corrective diagnosis.

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Kit Preparation and Biodistribution of $Bz-MAG_3$ (benzoylmercaptoacetylglycylglycylglycine) for Renal Imaging (신장기능영상용 방사성의 약품 $Bz-MAG_3$(Benzoylmercaptoacetylglycylglycylglycine) 의 키트화 및 체내분포)

  • Kim, Young-Ju;Jeong, Jae-Min;Cho, Jung-Hyuk;Chang, Young-Soo;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.30 no.3
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    • pp.367-371
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    • 1996
  • The $MAG_3$ is a tubular excreting radiopharmaceutical for renal image. We synthesized benzoyl $MAG_3\;(Bz-MAG_3)$ and made a kit for labeling with $^{99m}Tc$. We checked the labeling efficieny of $^{99m}Tc$ labeled $MAG_3$ and biodistribution. Labeling efficieny was checked by TLC-SG (acetonitrile/$H_2O$=2/1). After injecting of 1 mCi of $^{99m}Tc-MAG_3$ to ICR-mice, $T_{max}(min),\;T_{1/2}(min)$ were obtained in the renogram. Sequential images (30sec, 2min, 5min, 10min, 15min, 20min) of $^{99m}Tc-MAG_3$ were compared with those of commercial $^{99m}Tc$-DTPA (Du Pont Merck Pharmaceutical Co.) kit. 1) The $R_f$ value of synthesized $^{99m}Tc-MAG_3$ was 0.78 and labeling efficiency was $97.5{\pm}1.9%$ (n=10). 2) The dynamic images of the $^{99m}Tc-MAG_3$ were better than those of the $^{99m}Tc$-DTPA. 3) The $T_{max}(min.)$ and $T_{1/2}(min.)$ of $^{99m}Tc-MAG_3$ (n=10) were $1.5{\pm}0.5$ (left), $1.4{\pm}0.4$ (right), and $4.3{\pm}1.4$ (left), $4.8{\pm}2.0$ (right), respectively. The $T_{max}(min.)$ and $T_{1/2}(min.)$ of $^{99m}Tc$-DTPA (n=7) were $2.7{\pm}1.6$ (left), $2.7{\pm}1.6$ (right), and $3.8{\pm}1.7$ (left), $4.5{\pm}2.7$ (right), respectively. The quaility of image and labeling efficiency of the synthesized $Bz-MAG_3$ kit were excellent, that it was supposed to be used in routine clinical work.

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Effects of Water Temperature and Photoperiod on the Oxygen Consumption Rate of Fasted Juvenile Parrot Fish, Oplegnathus fasciatus (돌돔, Oplegnathus fasciatus 치어의 절식시 산소 소비율에 미치는 수온과 광주기의 영향)

  • Oh, Sung-Yong;Noh, Choong-Hwan;Kang, Rae-Seon;Myoung, Jung-Goo
    • Ocean and Polar Research
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    • v.28 no.4
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    • pp.407-413
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    • 2006
  • The effect of water temperature and photoperiod on the oxygen consumption of the fasted juvenile parrot fish, Oplegnathus fasciatus was investigated to provide empirical data for the early-stage culture management and bioenergetic growth model of the species. The mean body weight of the juvenile used for the experiment was $21.5{\pm}1.9g$, and the oxygen consumption rate was measured under four water temperatures (10, 15, 20 and $25^{\circ}C$) and three photoperiods (24L:0D, 12L:12D and OL:24D) with an interval of 5 minutes for 24 hours using a continuous flow-through respirometer. In each treatment three replicates were set up and 15 juveniles were totally involved. The oxygen consumption rates increased with increasing water temperature under all photoperiod treatments (P<0.001). Mean oxygen consumption rates at 10, 15, 20 and $25^{\circ}C$ ranged $202.1{\sim}403.4,\;306.7{\sim}502.2,\;536.7{\sim}791.0\;and\;879.9{\sim}1,077.4mg\;O_2\;kg^{-1}h^{-1}$, respectively. $Q_{10}$ values ranged $1.58{\sim}2.30$ between 10 and $15^{\circ}C,\;2.44{\sim}3.06$ between 15 and $20^{\circ}C\;and\;1.86{\sim}2.6y9$ between 20 and $25^{\circ}C$, respectively. Mean oxygen consumption rates of O. fasciatus were the highest in continuous light (24L:0D) followed by 12L:12D and 0L:24D (P<0.001). The oxygen consumption of fish exposed to the 12L:12D photoperiod was significantly higher during the light phase than during the dark phase under all temperature treatments (P<0.001). In summary, oxygen consumption rates of the juvenile parrot fish increase with increasing water temperature and lengthening daylight period; and, thereby, changes in water quality resulted from the depletion of oxygen under high temperature and long daylight photoperiod conditions should be monitored.