• Title/Summary/Keyword: reinforcing system

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Evaluation of biochemical and free radical scavengers of Digitaria exilis L. under osmotic stress

  • Oyinade A., David;Oluwole, Osonubi;Jacob, Oyetunji Olusola
    • Journal of Plant Biotechnology
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    • v.46 no.4
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    • pp.331-337
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    • 2019
  • Digitaria exilis L. is an under-utilized crop with high nutritional and medicinal values. It thrives in and is well-adapted to arid areas with low soil nutrients. Using biochemical markers, this study investigates the mechanisms by which D. exilis responds to osmotic stress. Three accessions Dinat Iburua (DIN), Jakah Iburua (JAK) and Jiw Iburua (JIW) were collected from National Cereal Research Institute, Niger State. Two accessions, NG/11/JD/061 and NG/11/JD/062 were also collected from National Centre for Genetic Resources and Biotechnology, Ibadan. Murashige and Skoog medium of approximately 1.2 L was supplemented with polyethylene glycol 6000 to create osmotic pressures of -9.29, -13.93, -20.13, -26.32, -32.51, and 0 MPa (control). Sterilized seeds were inoculated in the medium and placed in the growth room for 4 weeks. Proline accumulation was significantly high in all JAK plants under osmotic stress. Proline and ascorbate peroxidase (p<0.05) activities were directly correlated, thus reinforcing the survivability of JAK during stress. Catalase (CAT) activity was also significantly induced in JAK under osmotic stress, which synergistically improved its tolerability. As a result, >50% of OH-, H2O2, and NO radicals were scavenged. However, other accessions including DIN, NG061, NG062, and JIW showed variations in their responses to different levels of osmotic stress, although not significant. Therefore, JAK possesses a well-equipped free radical quenching system that is protected by the accumulation of the osmolyte proline; therefore, accession JAK is considered osmotolerant. CAT and superoxide dismutase activities were osmostabilized against oxidative stress by proline.

The Governance and Agent Problems of Public Agency: Focused on the Port Authority of New York and New Jersey (공기업 거버넌스 제도와 대리인 문제: 뉴욕.뉴저지 항만공사를 중심으로)

  • Kang, Yun-Ho
    • Journal of Navigation and Port Research
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    • v.33 no.10
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    • pp.743-756
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    • 2009
  • This paper tries to analyze how the governance institutions of the Port Authority of New York and New Jersey overcome agent problems in public agencies based on the Principal-Agent Theory, and find the implications that will be helpful to the governance of port authorities in Korea. The Port Authority's governance is characterized by decentralization of personnel rights, open meetings policy, freedom of information policy, public hearings, and fiscally self-supporting system. Those characteristics are helpful in overcoming the agent problems of public agency, such as adverse selection, moral hazard, and complicated external structure, through reinforcing of monitoring agent by principal, easing of information asymmetry between principal and agent, and clarification of organizational ownership structure. Those characteristics may give many implications for the design of governance structures of port authorities in Korea.

Effect of Acupuncture on Behavior and Dopamine Release in the Nucleus Accumbens in rats Sensitized to Morphine (몰핀 투여로 민감화된 실험동물의 행동 및 뇌 측핵의 도파민 유리에 대한 침 효과)

  • Lyu Yeoung Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.510-517
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    • 2003
  • Studies have shown that both the psychomotor stimulant effects and rewarding properties of addictive drugs, including morphine, are sensitized by repeated drug administration and it is suggested that both of these effects are mediated by the same or closely overlapping dopamine systems. Specifically, the mesolimbic dopamine system has been implicated in the reinforcing and sensitizing properties of morphine. In oriental medicine, Shenmen (HT7) point on the heart channel has been used to treat mental and psychosomatic disorders. This study was designed to investigate the effect of acupuncture on acute and repeated morphine-induced changes in extracellular dopamine levels using in vivo microdialysis and morphine-induced behavioral changes. In the morphine sensitization experiment, male Sprague-Dawley rats were treated twice a day for three days with increasing doses of morphine (10, 20 and 40 mg/kg, s.c.) or with saline. After 15 days of withdrawal, rats were challenged with morphine hydrochloride (5 mg/kg, s.c.). Acupuncture was applied at bilateral Shenmen (HT7) points for 1 min after the morphine challenge. In the acute experiment, rats also received acupuncture for 1 min after an injection of morphine hydrochloride (5 mg/kg, s.c.). Results showed that acupuncture at the specific acupoint HT7, but not at control points (tail) significantly decreased both dopamine release and behavior induced by a systemic morphine challenge or a single sc morphine injection in the acute animals. These results suggest that reduction in sensitization may be one mechanism whereby acupuncture alleviates morphine craving in addicts.

Manufacturing of High Water-Resistant Particleboard by Combining Use of Urea Resin and EMDI Resin (요소수지와 EMDI수지의 복합이용에 의한 고내수정 파티클보드의 제조)

  • Park, Jong-Young
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.1
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    • pp.97-105
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    • 1998
  • This study examined the combined using effects of urea-formaldehyde (UF) resin and emulsifiable methylene diphyenyl diisocyanate (EMDI) resin to overcome performance limit of three-layer particleboards commonly made by UF resin. Two adhesive adding methods were applied with three types of resin combination system to each layer of particleboards. The one was simultaneously spreading method with emulsified compound resin (UF and EMDI) while the other was separately spreading method with unemulsified EMDI resin after UF resin spreading. The performance of particleboards bonded with 2% EMDI resin to the inner layers(IL) were similar to that of controls bonded with 8% UF resin. In the case of the emulsified compound resin application to the all layers of particleboards, there were marked reinforcing effects of EMDI resin, although a small amount of EMDI resin was mixed with UF resin. Especially bending MOR after 24 hours cold water-immersion and thickness swelling after 2 hours hot water-immersion of compound resin-bonded particleboards were remarkably different from those of pure UF resin-bonded particleboards. It was found that separately spreading method with unemulsified EMDI resin was more effective than simultaneously spreading method with emulsified compound resin to sustain the internal bond strength of particleboards after 24 hours cold water-immersion. In the resin combination systems to outer layers/inner layers of particleboards, water resistance and strength properties were superior in order of UF+EMDI/UF+EMDI > UF/UF+EMDI > UF/UF. And water resistance of particleboards was greatly dependent upon EMDI resin level in any adhesive adding method.

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Dependence Potential of Propofol: Behavioral Pharmacology in Rodents

  • Cha, Hye-Jin;Cha, Ji-Hun;Cho, Hea-Young;Chung, Eun-Yong;Kwon, Kyoung-Jin;Lee, Jun-Yeon;Jeong, Ho-Sang;Kim, Hye-Soo;Chung, Hye-Joo;Kim, Eun-Jung
    • Biomolecules & Therapeutics
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    • v.20 no.2
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    • pp.234-238
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    • 2012
  • Propofol is an anesthetic commonly used to provide sedation or to induce and maintain an anesthetic stated. However, there are reports which indicate propofol may cause psychological dependence or be abused. In the present study, we used various behavioral tests including climbing test, jumping test, conditioned place preference, and self-administration test to assess the dependence potential and abuse liability of propofol compared to a positive control (methamphetamine) or a negative control (saline or intralipid). Among the tests, the conditioned place preference test was conducted with a biased method, and the selfadministration test was performed under a fixed ratio (FR) 1 schedule, 1 h per session. No difference was found in the climbing test and jumping test, but propofol (30 mg/kg, i.p.) increased the rewarding effect in the conditioned place preference test, and it showed a positive reinforcing effect compared to the vehicle. These results indicate that propofol tends to show psychological dependence rather than physical dependence, and it seems not to be related with dopaminergic system.

Implementation of Infant Learning Content using Augmented Reality (증강현실을 이용한 유아용 학습 콘텐츠의 구현)

  • Lee, Jong-Hyeok;Cho, Hyun-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.1
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    • pp.257-263
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    • 2011
  • Recently as AR(Augmented Reality) is focus of attention, AR is applied to various fields and is expected its valuable use. In this paper, we implemented the system based on Goblin XNA which supports high resolution model file and higher AR. We confirmed the relation of model output among the number of marker, the location and changes of camera distance. And we produced the infantile studying contents using AR and embodied. In implemented contents, we showed the familiar character to infants on each page marker. As the result of it, we can raise their concentration and at a time studying supporters can use the contents easily as well. Also we put 3 marker on each page of contents to recognize it smoothly in case one part of it is hidden by any obstacle. Finally we maximized the learning effect such as presence and immersion in studying through reinforcing 3D models according to the every situation.

Development of FRP Recycling Process for Regenerating Applications of Fire Resistance Performance of High Strength Concrete (고강도 콘크리트의 내화성능 용도에 따른 FRP재활용 공정 개발)

  • Lee, Seung Hee;Park, Jong Won;Yoon, Koo Young
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.3
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    • pp.207-215
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    • 2015
  • In the last decade, increasing national research fund for recycling the waste FRP (fiber reinforced plastics) ships which has caused environmental problems, improves the technology making concrete-reinforcing fibers out of the waste FRP. Furthermore, the concrete with recycled FRP fiber was tested for the structural performance. Experimental strength tests show that use of recycled FRP powder does not reduce the compressive strength of high strength concrete, and does increase the fire resistance performance of high strength concrete significantly. But, the study in investigating the properties of recycled fiber powder from waste FRP has not been completed because of the absence of the method of separation of mat layer from the waste FRP. This study is to propose a new extracting method of the mat layer from waste FRP, which is the efficient and environment friendly system. and thus it is considered to be the useful recycling method for fire resistance high concrete products or structures.

REINFORCEMENT OF ACRYLIC RESIN WITH METAL WIRE (금속 wire의 아크릴릭 레진 보강효과에 관한 연구)

  • Jeong, Chang-Mo;Jeon, Young-Chan;Lim, Chang-Sup
    • The Journal of Korean Academy of Prosthodontics
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    • v.34 no.4
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    • pp.823-832
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    • 1996
  • The purpose of this study was to assess the effect of 1) the diameter(0.7,1.0,1.2mm) and number(1,2,3) of commonly available orthodontic metal wires embedded in self-curing orthodontic acrylic resin specimens($64{\times}10{\times}3mm$) and 2) the use of chemical adhesive system(Silicoater, Metalprimer) to prevent slipping at the interface between the resin and the metal wire on reinforcement by using three-point bending test. From this study, the following results were obtained. 1. No statistically significant difference was found among the transverse strengths for the control without reinforcement, one 0.7mm wire, two 0.7mm wires, three 0.7mm wires, and one 1.0mm wire groups(P>.05). 2. In the groups with 1.0 or 1.2mm wires, the transverse strength increased in proportion to the increase of number of wires(P<.05). 3. In the groups with 0.7 or 1.0mm wires, neither of Silicoater and Netalprimer increased the transverse strength significantly(P>.05). 4. No statistically significant difference was found in transverse strength between Silicoater groups and Metalprimer groups with same diameter of wires(P.>05). From these result, it is concluded that diameter of wires is a primary considering factor to reinforce the acrylic resin effectively and, when this requirement is satisfied, increased number of wires or chemical adhesive systems can be expected to produce the additional reinforcing effect.

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A Study on the Seafarers Education for Cabotage in KOREA (한국의 카보타지를 위한 선원양성에 관한 연구)

  • Kim, Sung-Kuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.6
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    • pp.712-720
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    • 2015
  • The cabotage rule has been protecting the domestic industry from foreign competitions as a kind of trade barrier. In the United States, the shipbuilding industry has been maintained with the help of to the strict cabotage operations by reinforcing advantages for domestic crews and ships which are built in the U.S. For most countries, cabotage has been granted legitimacy in their coastal shipping by Low Carbon Transport in terms of economic and emergency reasons. The cabotage rule is required in the stable supply of the seafarers which rely on the legitimate maritime education. This study analyzes Korean cabotage system and the problems with regard to seafarers education. It is found that the resolution is set up the cabotage act such as Jones Act, U.S.

Crisis at Universities and the Practical Issues of Physical Education and Sports Related Departments (대학의 위기와 체육계열 학과의 실천적 과제)

  • Yi, Joo-Wook;Han, Dong-Soo;Yun, Dae-Hyun
    • Journal of Digital Convergence
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    • v.14 no.1
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    • pp.427-436
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    • 2016
  • Is university restructuring for 'reinforcing university education quality and competitiveness of higher education'? The fundamental problems of the on going university restructuring becomes crisis of university and moreover, Sports Related Departments faces huge crisis. This research analyzes university crisis and progress of Sports Related Departments. After conducting discussion about a directivity of Physical Education in university with a focus on role and direction of 'Physical Education' which is for realization of 'University''s ideal, Sports Related Departments proposed four practical tasks, which is for preventive improvement, not for prescriptive improvement. First, Effort to establish academical identity. Second, characterization strategy for each different region and university. Third, Reforming of Sports Related Departments related with prospect of the labour market. Last, Drawing up a plan for establishing Sports Related Departments' united system.