• 제목/요약/키워드: Suppression

검색결과 5,304건 처리시간 0.027초

Molecular Control of Gene Co-suppression in Transgenic Soybean via Particle Bombardment

  • El-Shemy, Hany A.;Khalafalla, Mutasim M.;Fujita, Kounosuke;Ishimoto, Masao
    • BMB Reports
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    • 제39권1호
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    • pp.61-67
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    • 2006
  • Molecular co-suppression phenomena are important to consider in transgene experiments. Embryogenic cells were obtained from immature cotyledons and engineered with two different gene constructs (pHV and pHVS) through particle bombardment. Both constructs contain a gene conferring resistance to hygromycin (hpt) as a selective marker and a modified glycinin (11S globulin) gene (V3-1) as a target. sGFP(S65T) as a reporter gene was, however, inserted into the flanking region of the V3-1 gene (pHVS). Fluorescence microscopic screening after the selection of hygromycin, identified clearly the expression of sGFP(S65T) in the transformed soybean embryos bombarded with the pHVS construct. Stable integration of the transgenes was confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Seeds of transgenic plants obtained from the pHV construct frequently lacked an accumulation of endogenous glycinin, which is encoded by homologous genes to the target gene V3-1. Most of the transgenic plants expressing sGFP(S65T) showed highly accumulation of glycinin. The expression of sGFP(S65T) and V3-1 inherits into the next generations. sGFP(S65T) as a reporter gene may be useful to increase the transformation efficiency of transgenic soybean with avoiding gene co-suppression.

산화막을 이용한 SiC 기판의 macrostep 형성 억제 (Suppression of Macrosteps Formation on SiC Wafer Using an Oxide Layer)

  • 방욱;김남균;김상철;송근호;김은동
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.539-542
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    • 2001
  • In SiC semiconductor device processing, it needs high temperature anneal for activation of ion implanted dopants. The macrosteps, 7~8nm in height, are formed on the surface of SiC substrates during activation anneal. We have investigated the effect of thermally-grown SiO$_2$layer on the suppression of macrostep formation during high temperature anneal. The cap oxide layer was found to be efficient for suppression of macrostep formation even though the annealing temperature is as high as the melting point of SiO$_2$. The thin cap oxide layer (10nm) was evaporated during anneal then the macrosteps were formed on SiC substrate. On the other hand the thicker cap oxide layer (50nm) remains until the anneal process ends. In that case, the surface was smoother and the macrosteps were rarely formed. The thermally-grown oxide layer is found to be a good material for the suppression of macrostep formation because of its feasibility of growing and processing. Moreover, we can choose a proper oxide thickness considering the evaporate rate of SiO$_2$at the given temperature.

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Positioning and vibration suppression for multiple degrees of freedom flexible structure by genetic algorithm and input shaping

  • Lin, J.;Chiang, C.B.
    • Smart Structures and Systems
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    • 제14권3호
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    • pp.347-365
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    • 2014
  • The main objective of this paper is to develop an innovative methodology for the vibration suppression control of the multiple degrees-of-freedom (MDOF) flexible structure. The proposed structure represented in this research as a clamped-free-free-free truss type plate is rotated by motors. The controller has two loops for tracking and vibration suppression. In addition to stabilizing the actual system, the proposed feedback control is based on a genetic algorithm (GA) to seek the primary optimal control gain for tracking and stabilization purposes. Moreover, input shaping is introduced for the control scheme that limits motion-induced elastic vibration by shaping the reference command. Experimental results are presented, demonstrating that, in the control loop, roll and yaw angles track control and elastic mode stabilization. It was also demonstrated that combining the input shaper with the proportional-integral-derivative (PID) feedback method has been shown to yield improved performance in controlling the flexible structure system. The broad range of problems discussed in this research is valuable in civil, mechanical, and aerospace engineering for flexible structures with MDOM motion.

The Design of a Small GNSS Receiver with Enhanced Interference Suppression Capability for High Mobility

  • Park, Yong-Hyun;Moon, Sung-Wook;Shin, Bong-Gyu;Oh, Jong-Su
    • Journal of Positioning, Navigation, and Timing
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    • 제4권1호
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    • pp.9-16
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    • 2015
  • The applications of Global Navigation Satellite System (GNSS) receivers are becoming wider in various commercial and military systems including even small weapon systems such as artillery shells. The precision-guided munitions such as Small Diameter Bomb (SDB) of United States can be used for pinpoint strike by acquiring and tracking GNSS signals in high mobility situation. In this paper, a small GNSS receiver with embedded interference suppression capability working under high dynamic stress is developed which is applicable to the various weapon systems and can be used in other several harsh environments. It applies a kind of matched filter and multiple correlator schemes for fast signal acquisition and tracking of even weak signals and frequency domain signal processing method to eliminate the narrowband interference. To evaluate the performance of the developed GNSS receiver, the test scenario of high mobility and interference environment with the GNSS simulator and signal generator is devised. Then, the signal acquisition time, navigation accuracy, sensitivity, and interference suppression performances under high dynamic operation are evaluated. And the comparison test with the commercial GNSS receiver which has high sensitivity is made under the same test condition.

캐비테이션 감소를 위한 혼타의 형상 연구 (A Study on the Rudder Shapes for the Suppression of Cavitation around a Horn-type Rudder)

  • 박경령;이영길
    • 대한조선학회논문집
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    • 제47권4호
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    • pp.553-564
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    • 2010
  • This paper studies on the rudder shapes for the suppression of the cavitation around a horn-type rudder. To improve the problems due to cavitation, there have been several studies. However, these some studies are recognized as incomplete ways to suppress the rudder cavitation. In this study, the section shapes to suppress the cavitation phenomena are determined by moving the location of maximum thickness for reducing the curvature variation and changing the radius of leading edge. Also, in the pintle part, the curvature radius of the inlet outlet edge of rudder plate is changed. During the design of rudder shape, two-dimensional numerical simulations are firstly performed because those offer some advantages with that cavitation phenomena becomes predictable for a short time, and then the three-dimensional numerical simulations are performed to confirm the determination. The time mean distribution of the propeller slipstream is imposed on the inlet boundary condition. As some results, this paper shows the effects reducing the range of the occurrence of cavitation, and suggests the references on the design of a horn-type rudder for the suppression of cavitation phenomena.

축방��으로 전개되는 보의 중력에 의한 횡진동 저감 연구 (A Study on Suppression of Lateral Vibration for Axially Deploying Beams under Gravity)

  • 임재곤;윤원상;범희락;홍성욱
    • 한국정밀공학회지
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    • 제28권8호
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    • pp.959-965
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    • 2011
  • This paper presents the dynamic modeling and vibration suppression methods for axially deploying beams subjected to gravity. A modal modeling method is employed to develop the lateral vibration model for axially deploying beams. Simulation is made to validate the proposed model as well as to investigate the dynamics of axially deploying beams. This paper rigorously investigates the gravity effect as a source of vibration for axially deploying beams. In order to suppress lateral vibration for deploying beams, the moving speed command is modified by using the input shaping method, Experiments are also performed to prove the proposed vibration suppression method. The simulations and experiments show that the proposed modeling and input shaping methods are effective for the dynamic analysis and vibration suppression of axially deploying beams subjected to gravity.

이동식 미분무수 노즐의 소화 특성에 대한 수치 시뮬레이션 (Thermal Numerical Simulation on Fire Suppression Characteristics through Mobile Mist Spray Nozzles)

  • 배강열;정희택;김형범;정인수;김창
    • 동력기계공학회지
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    • 제13권5호
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    • pp.25-33
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    • 2009
  • In the present study, the numerical investigation has been carried out to see the effects of water mist sprays on the fire suppression mechanism. The special-purposed program named as FDS was used to simulate the interaction of fire plume and water mists. This program solves the fire-driven flows using LES turbulence model, the mixture fraction combustion model, the finite volume method of radiation transport for a non-scattering gray gas, and conjugate heat transfer between wall and gas flow. The computational domain was composed of a rectangular space dimensioned as $L{\times}W{\times}H=4.0{\times}4.0{\times}2.5\;m^3$ with a mist-injecting nozzle installed 1.0 m high from the fire pool. In this paper, two types of nozzles were chosen to compare the performance of the fire suppression. Numerical results showed that the nozzle, type A, with more orifices having smaller diameters had poorer performance than the other one, type B because the flow injected through side holes deteriorated the primary flow. The fire-extinguishing time of type A was 2.6 times bigger than that of type B.

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STORAGE OF BROCCOLI BY MAKING THE WATER STRUCTURED -Suppression of metabolism-

  • Oshita, S.;Seo, Y.;Kawagoe, Y.;Rahman, M.A.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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    • pp.918-925
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    • 1996
  • The effect of structured water by dissolution of xenon was examined from the view point of the suppression of both browning and respiratory metabolism of broccoli. The structured water is formed duet to hydrophobic interaction when xenon gas dissolves into water. NMR measurements were carried out to determine proton spin-spin relaxation time, T2, for water. There was a difference in proton T2 between distilled water and structured water. This can be interpreted as the change of water structure. Fro the broccoli cut in half stored for 16 days at 279K, the section color did not change appreciably for the sample whose water was structured by dissolution of xenon whose initial partial pressure was 0.39MPa. In contrast to this, the browning of section surface was observed for the sample stored under the condition of nitrogen gas at the same partial pressure as xenon and for the sample stored under atmospheric condition . These results led to the conclusion that the suppression of b owning by oxidation was due to structured water but not to applied pressure. Adding to this, the water structured by xenon has resulted in suppression of respiratory metabolism of broccoli.

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Effects of Panax ginseng on Morphine-induced Immune Suppression

  • Lee, Shee-Yong;Kim, Ae-Young;Kim, Young-Ran;Kim, Kyeong-Man
    • Biomolecules & Therapeutics
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    • 제3권3호
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    • pp.177-181
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    • 1995
  • To investigate the possibility of Panax ginseng as a therapeutic agent for the immune suppression, ginseng total saponin (GTS) extracted from korean red ginseng was tested on immune functions from morphine-induced immune suppressed mice. To study how immune functions are affected by morphine and also to test whether GTS can be an useful therapeutic agent for morphine toxicity, several parameters were employed, body weight, immune organ weight, B cell functions, and T cell function. Morphine impaired the development of body weight and immune organ weight such as spleen and thymus. Morphine also depressed a B-cell function, antibody production. T-cell functions studied by type IV hypersensitivity test were most markedly affected by morphine treatment. GTS restored most of morphine-induced immune suppression. GTS restored the morphine-induced decrease in spleen weight to body weight ratio in a dose dependent manner, but not the body weight decrease. Also all of the morphine-induced impairments of B cell functions and cellmediated immunity were fully recovered by GTS. These results suggest that ginseng product could be very helpful for the treatment of immune suppression occurring in morphine abusers.

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물리치료사의 정서억제와 직무탈진이 직무만족에 미치는 영향 (Effects of the Emotional Suppression and Burnout on the Job Satisfaction among Physical Therapists)

  • 배원식;이건철;오혜원
    • 대한물리의학회지
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    • 제6권2호
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    • pp.177-187
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    • 2011
  • Purpose: The purpose of this study was to identify the effect of emotional suppression and burnout on the job satisfaction. Methods: We distributed questionnaires to 216 physical therapists and collected completed questionnaires from 193. We analyzed the data using frequency analysis, independent t-tests, analysis of variance. and multiple regression. Results: The results were as follows; 1) General characteristics of participants were 62.7% male, 43.5% less 30 years old, 31.6% working over 10 years in the hospital. 27.1% participants treated 31 patients or more a day, most(85.5%) participants were regular staff members. 2) Emotional Suppression, exhaustion and diminished self-efficacy were significantly correlated with job satisfaction. According to result of regression analysis on the job satisfaction, the job satisfaction negatively related with the diminished self-efficacy, exhaustion but positively related with the emotional supression. Their power of explanation regarding job satisfaction was 31.2%. Conclusion: These results showed that diminished self-efficacy was importantly influenced on the job satisfaction. So this result of the study means that we must improve the stratege for keeping efficient management.