• Title/Summary/Keyword: 24h temperature

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Serratia marcescens ATCC 21074 로 부터 순수분리한 Metalloprotease 의 자가분해성과 안전성

  • 김기석;이창원;이병룡;신용철
    • Korean Journal of Microbiology
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    • v.30 no.2
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    • pp.71-77
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    • 1992
  • A 50 KD metalloprotease of Serratia marcesrens ATCC 21074 was purified by ammoniumsulfate precipitation. DEAE-cellulose ion exchange chromatography, and sephadex ti-100gel filtration. Optimal pH and temperature of enzyme were pH 8.0 and 37"C, respectively.This enzyme was stable in the ranges of 10-37$^{\circ}$C and pH 5.0--11.0. Thermal denaturationwas investigated by differential scanning calorimetry. Onset temperature of denaturationand endothermic peak temperature were 376$^{\circ}$C and 43.2"C. re:,pectively. The denaturationenthalpy was -8.4mJimg. The purified metalloprotease was ri.sistant to autodigestion for24 hr at 30$^{\circ}$C. Metalloprotease in culture supernatant was also resistant to autodigestionin this conditions. Heat-denatured enzyme. however. was rapidly digested by the nativeenzyme. The metalloprotease was stable to proteolytic digestion by mammalian proteasessuch as trypsin. a-chymotrypsin, and elastase. But the enzyme was easily digested bybacterial protease. thermolysin.bacterial protease. thermolysin.

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Histopathological study of acute toxicity of ammonia to the eel, Anguilla japonica in high temperature and pH levels (고수온(高水溫) 고(高)pH에서 뱀장어에 미치는 암모니아 급성독성(急性毒性)의 병리조직학적(病理組織學的) 연구(硏究))

  • Kim, Min-Soo;Yang, Han-Choon
    • Journal of fish pathology
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    • v.9 no.2
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    • pp.147-155
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    • 1996
  • This study was carried out to examine the acute toxic effects of ammonia to the eel, Anguilla japonica in high temperature and pH levels by histopathological observations. The eels of 40 g average body weight were exposed to 4 different concentrations of total ammonia (0, 10, 20, 30 mg/$\ell$) for 24~120 hours. Each concentration was treated under 4 different levels of pH (7.5, 8.0, 8.5, 9.0) and each of these treatments was tested at 2 different temperatures ($27^{\circ}C$, $32^{\circ}C$). Histopathological changes in gill tissues were observed by hematoxylin-eosin stain. As increasing of pH (from 7.5 to 9.0), water temperature (from $27^{\circ}C$ to $32^{\circ}C$), total ammonia concentration (from 0 mg/$\ell$ to 30 mg/$\ell$) and exposure time (from 24 hours to 120 hours), gill discolorated to dark brown with the naked eye and gill tissues showed hypertrophy of gill lamellae, winding of the secondary gill lamellae, epitherial separation and necrosis histopathologically. When gill lamellae epithelium was separated from the blood vessels, gill discolorated to dark brown with the naked eye.

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Growth Responses and Regrowth to Low Temperature of Nine Native Moss Species

  • Gong, Gyeong Yeop;Jeong, Kyeong Jin;Lee, Sang Woo;Yun, Jae Gill
    • Journal of People, Plants, and Environment
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    • v.22 no.6
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    • pp.575-582
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    • 2019
  • Moss is used as an important material in indoor landscaping as well as outdoor landscaping. Moss is vivid green during growth and excellent in ornamental value. But when temperature drops, moss stops growth, turns brown or loses its ornamental value. In the present experiment, for the purpose of classifying native mosses according to the growth response to low temperature, the temperature of the plant growth chamber was set to 15℃/5℃ (16h/8h, day/night) and 5℃ (24h) for 8 weeks using nine native moss species. Thereafter, the temperature of the plant growth chamber was set to 20℃, and then the changes of moss block area and moss color were measured. The changes of moss block area and moss color were measured using a Photoshop program, after each moss block was photographed. As a result, Atrichum undulatum (Hedw.). Beauv., Etodon luridus (Griff.) A. Jaeger, Bachythecium plumosum (Hedw.) Schimp, Plagiomnium cuspidatum (Hedw.) T.J. Kop, and Hypnum plumaeforme Wilson showed a small decrease in moss block area at low temperature, and their recovery were the fastest at 20℃. These three species had higher green values at low temperature compared to other species, and the greenness increased rapidly at 20℃. On the other hand, Atrichum undulatum (Hedw.). Beauv., Marchantia polymorpha L., and Thuidium cymbifolium (Mitt.) A. Jaeger showed the smallest block area at low temperature and the lowest recovery even at 20℃. Their green values also decreased significantly at low temperature, and maintained low green value even at 20℃. These results showed that these three moss species are sensitive to low temperature. The remaining Myuroclada maximowiczii, Plagiomnium cuspidatum, and H. erectiusculum showed moderate responses to low temperature compared to other six species of mosses.

Effect of Hydration Condition of Non-Muscle Protein on Gelling (비근육 단백질의 수화조건이 겔 형성에 미치는 영향)

  • Cho Min Sung;Lee Nahm Gull;Cho Young Je
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.6
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    • pp.627-632
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    • 2002
  • This study was investigated the changes of gel properties about pH, color and water holding capacity at various hydration time and temperature of food-grade additives (BPP: bovine plasma protein, DEW: dried egg white, SPI: soy protein isolate). The changes of rheological properties were checked about hydration time and temperature. Hydration time and temperature affected pH value, hydration decreased pH of SPI and DEW. The BPP was not influenced at hydration time and temperature. Some Hydration condition increased jelly strength of food-grade additive, but SPI did not form a gel at all hydration condition. Hydration increased lightness of food-protein.

Oxygen Consumption of Hybrid Striped Bass (Morone chrysops ♀ M. saxatilis ♂) Exposed to Different Temperature, Salinity and Photoperiod (수온, 염분 및 광주기에 따른 잡종 striped bass (Morone chrysops ♀ ${\times}$ M. saxatilis ♂)의 산소소비)

  • 임한규;정민환;한형균;이종하;장영진
    • Journal of Aquaculture
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    • v.17 no.4
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    • pp.258-261
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    • 2004
  • The Oxygen consumption of hybrid striped bass (Morone chrysops ♀ M. saxatilis ♂) was measured in relation to water temperature, salinity and photoperiod changes. Fish (574.0101.3 g) was individually exercised in a chamber for 24 h at 2$0^{\circ}C$, 24$^{\circ}C$ and 28$^{\circ}C$ with two salinity conditions (0 and 33 psu). Stepwise, the increase of water temperature induced a strong increase of the oxygen consumption. Salinity and photoperiod had an influence on the oxygen consumption of hybrid striped bass, even though there was not a consistent tendency between those.

Dimensional Responses of Wood Under Cyclical Changing Temperature at Constant Relative Humidity

  • Yang, Tiantian;Ma, Erni;Shi, Yi
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.5
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    • pp.539-547
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    • 2015
  • To investigate dimensional responses of wood under dynamic temperature condition, poplar (populous euramericana Cv.) specimens, 20 mm in radial (R) and tangential (T) directions with two thicknesses of 4 and 10 mm along the grain, were exposed to cyclic temperature changes in square wave between $25^{\circ}C$ and $40^{\circ}C$ at 60% relative humidity (RH) for three different cycling periods of 6 h, 12 h and 24 h. R and T dimensional changes measured during the cycling gave the following results: 1) Transverse dimensional changes of the specimens were generally square but at an opposite phase and lagged behind the imposed temperature changes. The phase lag was inversely correlated with cycling period, but positively related to specimen thickness, while the response amplitude was directly proportional to cycling period, but in a negative correlation with specimen thickness. 2) The specimens showed swelling hysteresis behavior. The heat shrinkage coefficient (HSC) became greater as cycling period increased or specimen thickness decreased. 3) Dimensional changes of the specimens produced deformation accumulation during repeated adsorption and desorption. The deformation accumulating ratio decreased with an increase in cycling period and specimen thickness. 4) Wood suffered 1.5 times as many dimensional changes per unit temperature variation as per unit humidity variation, and this deformation behaved even more seriously under static condition.

Effect of Water Temperature and Photoperiod on the Oxygen Consumption Rate of Juvenile Pacific Cod Gadus macrocephalus (대구 Gadus macrocephalus 치어의 산소 소비율에 미치는 수온과 광주기의 영향)

  • Oh, Sung-Yong;Park, Heung-Sik;Kim, Chong-Kwan
    • Ocean and Polar Research
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    • v.32 no.3
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    • pp.229-236
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    • 2010
  • A study was conducted to investigate the effect of water temperature and photoperiod on the oxygen consumption of the fasting juvenile Pacific cod Gadus macrocephalus (mean body weight 79.9${\pm}$2.0 g) in order to quantify metabolic response of the species under given conditions. The oxygen consumption rate (OCR) of G. macrocephalus was measured under a combination of four different water temperatures (7, 10, 13 and $16^{\circ}C$) and three different photoperiods (24L:0D, 12L:12D and 0L:24D) with an interval of 5 minutes over a 24-hour period using a closed recirculating respirometer. Three replicates were set up in each treatment. OCRs increased with increased water temperatures under all photoperiod conditions (P<0.001). Mean OCRs at 7, 10, 13 and 16oC ranged from 793.7~1108.4, 1145.7~1570.3, 1352.8~1742.5 and 1458.2~1818.6 mg $O_2$ $kg^{-1}$ $h^{-1}$, respectively. Under all water temperature conditions except $7^{\circ}C$ (P<0.001), mean OCRs of G. macrocephalus were the highest in continuous light (24L:0D) followed by 12L:12D and 0L:24D photoperiods. Mean OCRs of fish exposed to the 12L:12D photoperiod were significantly higher during the light phase than during the dark phase under all temperature conditions (P<0.001). $Q_{10}$ values ranged from 3.19~5.13 between 7 and $10^{\circ}C$, 1.41~1.74 between 10 and $13^{\circ}C$ and 1.15~1.35 between 13 and $16^{\circ}C$, respectively. Based on overall results, water temperature, photoperiod and their combinations exerted a significant influence on the metabolic rate of juvenile cod. This study provides empirical data for estimating the amount of oxygen demand and managing the culture of cod under the given water temperatures and photoperiods.

A Fully Integrated SoC for Smart Capsule Providing In-Body Continuous pH and Temperature Monitoring

  • Liu, Heng;Jiang, Hanjun;Xia, Jingpei;Chi, Zhexiang;Li, Fule;Wang, Zhihua
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.5
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    • pp.542-549
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    • 2016
  • This paper presents a SoC (System-on-a-Chip) dedicated for a single-chip smart capsule which can be used to continuously monitor human alimentary canal pH and temperature values. The SoC is composed of the pH and temperature sensor interface circuit, a wireless transceiver, the power management circuit and the flow control logic. Fabricated in $0.18{\mu}m$ standard CMOS technology, the SoC occupies a die area of ${\sim}9 mm^2$. The SoC consumes 6.15 mW from a 3 V power supply, guaranteeing the smart capsule battery life is no less than 24 hours when using 50 mAh coin batteries. The experimental results show that measurement accuracy of the smart capsule is ${\pm}0.1$ pH and ${\pm}0.2^{\circ}C$ for pH and temperature sensing, respectively, which meets the requirement of in-body pH and temperature monitoring in clinical practice.

Comparisons of Handling Practices of Culled Sheep Meat for Production of Mutton Curry

  • Mendiratta, S.K.;Kondaiah, N.;Anjaneyulu, A.S.R.;Sharma, B.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.5
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    • pp.738-744
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    • 2008
  • In most developing countries consumers purchase retail cuts from hot carcasses and prepare traditional meat products as per their convenience and requirements. In this study, effects of different post mortem handling practices on quality of meat curry from culled sheep meat have been studied. After slaughter, leg cuts were subjected to nine commonly prevalent handling conditions in India viz. deboning (boning out) and cooking within 2-3 h (1), deboning immediately and cooking after 5-6 h (2), deboning after 5-6 h and cooking (3), deboning immediately, storage at $4^{\circ}C$ for 24 h and cooking (4), chilling for 24 h at $4^{\circ}C$, deboning and cooking (5), deboning after 5-6 h, storage for 24 h at $4^{\circ}C$, and cooking (6), deboning after 5-6 h, storage for 48 h at 4??C and cooking (7), deboning after 5-6 h, freezing and cooking (8), deboning after 5-6 h, storage for 24 h at $4^{\circ}C$, freezing and cooking (9). Significant differences were observed in pH, water-holding capacity, cooking loss and shear force values. Sensory scores were significantly higher in conditions (1), (5) and (9), and significantly lower in conditions (4) and (6). From the results, it was concluded that, to have the best quality product, meat should be cooked either immediately after slaughter or should be deboned just before cooking. Storage of deboned meat at refrigerated temperature must be avoided.

Characteristics of Culture for Emulsive Biosurfactant-Strain from the Soil (토양으로부터 분리한 유화성 생체계면활성 균주의 배양 특성)

  • 임윤택;윤용수
    • Journal of environmental and Sanitary engineering
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    • v.11 no.3
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    • pp.69-77
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    • 1996
  • The result of isolated and selected to the strain having the emulsifying activity from soil's strain the strain was identified as Candida genus. The strain was investigated with culture condition at pH culture temperature, flow rate of air, strring rate etc., and physicochemical properties of the biosurfactant were examined. The optimum composition of medium for a strain cultivation were obtained as follow : glucose ; 100g/L, yeast extract ; 10g/L, urea ; 1.0g/L, KH$_{2}$PO$_{4}$ ; 50mg/L, MgSO$_{4}$ ; 500mg/L, and the op condition of cultivation was as follow : pH ; 3.0, temperatlue ; 24$\circ $C, strring rate ; 40rpm. The maximum yield of biosurfactant was obtained by pH ; 3.0-3.5, and temperature ; 25$\circ $C. The degree of emulsification of syntesized biosurfactant was increased clearly by increasing concentration of biosurfactant and it's stability was maintained for a long time. The surface tension of biosurfactant was varied with pH, especially it was showed that the surface tension was high at acidic pH.

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