• Title/Summary/Keyword: 억제요인

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Screening of Antibrowning Agents for Minimally Processed Vegetables (최소가공채소류에 적합한 갈변방지제의 선발)

  • Park, Woo-Po;Cho, Sung-Hwan;Lee, Dong-Sun
    • Korean Journal of Food Science and Technology
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    • v.30 no.2
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    • pp.278-282
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    • 1998
  • Peeled garlic, soybean sprouts, cut onion and cut green pepper were treated by dipping in solutions of different antibrowning agents, and then stored at $10^{\circ}C$. Surface color and polyphenol oxidase activity of produce were measured through the storage. Tested antibrowning agents include ascorbic acid, citric acid and allyl isothiocyanate. The commodities showed different responses to the antibrowning agent solutions; 1% citric acid for peeled garlic, 1% ascorbic acid for soybean sprouts, 2% citric acid for cut onion, and 1% ascorbic acid for cut green pepper showed better retardation in browning than the other treatments for respective product. For peeled garlic, surface browning was concomitant with increase in polyphenol oxidase activity during storage. On the other hand, there was no positive correlation between surface browning and polyphenol oxidase activity for the other stored products.

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Influence of Atmospheric Vapor Pressure Deficit on Fruit Fermentation of Oriental Melon(Cucumis melo L. var makuwa Makino) (대기 증기압차가 참외 발효과 발생에 미치는 영향)

  • Shin, Yong-Seub;Seo, Young-Jin;Choi, Chung-Don;Park, So-Deuk;Choi, Kyung-Bae;Yoon, Jae-Tak;Kim, Byung-Soo
    • Journal of Bio-Environment Control
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    • v.16 no.3
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    • pp.174-179
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    • 2007
  • Although the relationship between fermentation and factors such as soil water, redox potential, rootstocks and climatic conditions has been reported, its mechanism of fermentation is still not clear. Transpirations of leaf and fruit at different climatic conditions, influence of soil water potential and atmospheric vapor pressure deficit (VPD) on fermentation were evaluated. Transpiration rate decreased with decreasing soil temperature and soil water potential. Low VPD conditions which occurred during low air temperature and high humidity also decreased transipration rate. These data exhibit that fruit water balance affected by various factors relate to transpiration. Our results also indicate that high hydraulic conductance of root, high soil water potential and low VPD condition exert a significant effect on fermention of oriental melon and so called "water filled fruit".

Effect of La and Si Addition on Thermal Stabilization of Alumina (La 및 Si 첨가에 의한 알루미나의 열안정화 효과)

  • Lee, Chae-Hyun;Lim, Dae-Young;Kim, Jong-Ock;Seo, Doo-Won;Han, Moon-Hee
    • The Journal of Engineering Research
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    • v.3 no.1
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    • pp.215-222
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    • 1998
  • The effect of La and Si addition of the thermal stabilization of $\gamma-alumina$ powers have been studied. Reagent grade $La(NO_3)_3{\cdot}6H_2O$ and $Si(OC_2H_5)_4$ were used as starting materials. These additives were introduced by wet impregnation method. Both La and Si additives suppressed the sintering of alumina and were found to be good thermal stabilizers of $\gamma-alumina$. Especially, Si drastically suppressed the phase transition of alumina at high temperatures. The major mechanisms for the thermal stabilization of alumina were seemed to be new phase formation and retardation of surface diffusion by addition of La or Si into alumina matrix.

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Effects of Cations on Adventitious Bud Formation on the Midvein of Leaf Segment in Poplar (포플라 잎절편의 중늑에서 부정아 형성에 미치는 양이온의 영향)

  • 김수진
    • Journal of Plant Biology
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    • v.34 no.1
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    • pp.25-30
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    • 1991
  • This study was designed to investigate the relationships of cations to the polar regeneration of adventitious buds on midvein segments of poplar leaves. Basal regeneration was disturbed by adding $Ca^{2+}$. When higher concentration of exogeneous $Ca^{2+}$ was added to the WPM (Woody Plant Medium), the more adventitious buds were formed on midvein segments, and polar regeneration was inhibited. Added $Ca^{2+}$ from 0 to 9.70 mM with 0.5 mM of EGT A to WPM decreased the calcium effect. The treatment of $La^{3+$ with 7.05 mM of $Ca^{2+}$ ovecame the effect of $Ca^{2+}$. The cations $Mg^{2+}\;and\;K^{+}$ also caused regeneration on both basal and distal site. However, polar regeneration was maintained in the medium containing $Ca^{2+}$ without $Mg^{2+}$. The above result suggests that exogenous $Ca^{2+}$ or cations inhibit polar regeneration of poplar.poplar.

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Factors Affecting Lipid Oxidation Development in High pH Ground Pork (고 pH 돈육 내의 항산화 기작)

  • Whang, Key;Kim, Hyuk-Il;Ha, Young-Duck
    • Korean Journal of Food Science and Technology
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    • v.25 no.5
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    • pp.517-520
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    • 1993
  • As the pH of ground pork increased from 5.0 to 7.0, the corresponding development of 2-thiobarbituric acid reactive substance (TBARS) during storage at $4^{\circ}C$ decreased significantly (p<.001). At the 4th day of refrigerated storage, with the increase in pH of ground pork from 5.0 to 7.0, the release of free iron decreased significantly (p<.05) from 1.50 to .99 ppm. The decrease in free iron content of pH 7 pork well explains the decrease in TBARS absorbances. The fact that the addition of 2% ethylenediamine tetraacetic acid (EDTA) to pH 5 ground pork decreased the oxidative rancidity development (p<.001) strongly supported the above finding that the increased free iron content of pH 5ground pork catalyze the oxidation during storage. The activity of glutathione peroxidase (GPx) at the 4th day of refrigerated storage decreased significantly (p<.05) when the pH of ground pork decreased from 7.0 to 5.0. Both the lower free iron content and the higher activity of GPx were proved to be important factors in controlling the oxidative rancidity of high pH ground pork.

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Effect of Dimethyl Amiloride on the Acrosome Reaction in Mouse Epididymal Sperm in vitro (생쥐 정자의 첨체반응에 미치는 Dimethyl Amiloride의 영향)

  • 계명찬
    • Development and Reproduction
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    • v.3 no.1
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    • pp.87-93
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    • 1999
  • The possible role of Na$^{+}$/H$^{+}$ antiporter in both the capacitation and the acrosome reaction (AR) was examined in mouse epididymal spermatozoa. Spontaneous acrosome reaction was inhibited by dimethyl amiloride (DMA), a specific inhibitor of Na$^{+}$/H$^{+}$ antiporter, with dose dependent manner. Follicular fluid- or A23l 87-induced acrosome reaction was not inhibited by DMA. It suggests that change in pH$_{i}$ by monovalent cation transport through the Na$^{+}$/H$^{+}$ antiporter is possibly engaged in the capacitation and that agonist- as well as A23l87-induced AR in capacitated sperm might be independent from the Na$^{+}$/H$^{+}$ antiporter. Conclusively, changes in pH$_{i}$ through the Na$^{+}$/H$^{+}$ antiporter might be important for sperm capacitation and it virtually occurs upstream of the $Ca^{2+}$ influx which precedes the acrosome reaction in mouse epididymal spermatozoa.pididymal spermatozoa.

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A Study on Development of an Anti-Rolling System for the Ship Stability Improvement (선박안정성 향상을 위한 횡동요 방지 장치 개발에 관한 연구)

  • Kim, Young-Bok;Lee, Kwon-Soon;Kim, Jun-Hyo;Chae, Gyu-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.11 no.1 s.22
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    • pp.23-28
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    • 2005
  • We have investigated the usefulness cf active stabilizing system to reduce ship rolling under disturbances, using varying reaction cf the flaps. In the proposed anti-rolling system for a ship, the flaps as the actuator are installed on the stem to reject rolling motion induced by disturbances like wave. The action induced by flaps which depends on power of disturbances am take the ship balance. Especially, in this study we identify the controlled system under the undefined system structure using spectral analysis and experimental studies. Based on these informations, we design the controller to evaluate the usefulness of the proposed system.

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Studies on the Cleavage Inhibidng Activity in the Cytoplasm of Growing Follicular Oocytes in Mammals (성장중인 포유동물 여포난자 세포질의 난할억제효과에 관하여)

  • 이원교;권혁방
    • The Korean Journal of Zoology
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    • v.33 no.1
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    • pp.45-52
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    • 1990
  • In order to determine whether maturation inhibiting activity(MIA) in the cytoplasm of growing follicular oocytes would suppress the cleavage of the embryonal cells, the growing oocytes were fused with the 2 or 4 cell blastomeres and then examined for the nuclear phase of the fused giant cells 24 hr after culture. A significant number of the giant cells(60%) composed of growing mouse oocyte and 2 cell mouse blastomere(1/2) in interphase has contained 2 nuclei 24 hr after culture and most of the giant cells (90%) composed of the growing oocyte and 4 cell blastomere(1/4) also contained 2 nuclei after culture. The unfused blastomeres or the isolated blastomeres cultured without fusion treatment cleaved one cell cycle under the same culture condition. In contrast, the nucleus of the growing oocytes was disintegrated and the chromosome condensed when fused with 2 cell blastomere in mitosis. The growing rat oocytes also suppressed the nuclear disintegration of the mouse embryonal cells during culture. The data presented here showed that MIA in the growing mammalian oocyte inhibited the cleavage of the embryonal cells in interphase stage, but not in milosis stage.

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Factors Affecting Deviation Broadcasting Intentions of Internet Personal Broadcasting Jockey: From the Perspective of the Social Pressure of Viewers (인터넷 개인 방송 진행자들의 일탈 방송의도에 영향을 미치는 요인: 시청자의 사회적 압력 관점에서)

  • Chae, Seong Wook;Song, Hye Ji
    • Knowledge Management Research
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    • v.23 no.2
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    • pp.169-192
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    • 2022
  • With the spread of Internet personal broadcasting service, the number of personal broadcasting hosts (BJs: Broadcasting Jockeys) and viewers is increasing, and immediate communication between them is also actively taking place. This study examines whether the mechanism to suppress deviant behavior of BJ works effectively and how viewers interacting with BJs affect the intentions of deviant behaviors of BJs. Through the structural equation model, the effect of formal and informal sanctions of deterrence theory on BJs' intention of deviant broadcasting through their policy compliance attitude was investigated. The moderating effect of social pressure on the relationship between BJs' policy compliance attitude and their deviant broadcasting intention was confirmed. A total of 234 data were analyzed by surveying Africa TV BJs. As a result of the analysis, it was found that informal as well as formal sanctions increased the BJs' attitude toward policy compliance. However, it was confirmed that the social pressure perceived by BJs from Internet personal broadcasting viewers reduced the effect of policy compliance attitudes on reducing deviant broadcasting intentions.

Reduction of Differential Settlements due to Deep Excavation Using the Micro-piling Method (마이크로 파일을 이용한 가설 벽체 인접 구조물의 침하 억제에 관한 연구)

  • Huh, In-Goo;Hwang, Tae-Hyun;Lee, Sang-Ryeong;Shin, Jong-Ho;Kwon, Oh-Yeob
    • Journal of the Korean Geotechnical Society
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    • v.24 no.10
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    • pp.71-81
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    • 2008
  • Wall displacements caused by earth pressure, rainfalls, rise in ground water level, inappropriate deep excavation and structural defects of the wall may produce differential settlements to existing buildings, which often result in damages and/or collapses of the building structures. In this case, measures to protect the walls and nearby structures would be required. One of the recent measures to reduce differential settlements and protecting walls is to reinforce the ground using micro-piles. In this study physical model tests were carried out to evaluate the performance of the micro-pile method. It is revealed that reduction of the settlement was maximized when the length of micro-pile is twice of the foundation width, distance between piles is twice of the pile diameter and the distance to wall is one tenth of the foundation width. Based on the test results some design recommendations were made.