• 제목/요약/키워드: Hi-tech

검색결과 231건 처리시간 0.026초

한강수계 상천천에서 한강납줄개 Rhodeus pseudosericeus와 떡납줄갱이 R. notatus의 종간 자연잡종 출현 (Occurrence of a Natural Interspecific Hybrid between Rhodeus pseudosericeus and R. notatus in Sangcheon Stream of the Han River, Korea)

  • 곽영호;김근용;김근식;송하윤
    • 생태와환경
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    • 제53권3호
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    • pp.275-285
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    • 2020
  • 한강수계 상천천에서 한강납줄개 Rhodeus pseudosericeus와 떡납줄갱이 R. notatus의 잡종으로 추정되는 2개체를 채집하였다. 자연잡종 개체의 체색은 황갈색으로 한강납줄개와 떡납줄갱이의 중간적인 특성을 나타냈지만, 전반적으로 떡납줄갱이의 특징이 두드러졌다. 계수 및 계측형질에서 등지느러미 기조수, 뒷지느러미 기조수, 종렬비늘 수의 3가지 형질은 hybrid index (HI) 값이 0으로 나타나 떡납줄갱이의 형질을 따랐다. 체장에 대한 등지느러미 기점 거리 (HI=74.6), 뒷지느러미 기점 거리 (HI=75.3), 배지느러미 기점 거리 (HI =77.6)는 한강납줄개의 형질을 따르는 것으로 나타났다. 새파수(HI=55.3), 체장에 대한 체고(HI=67.9), 두장에 대한 문장(HI=43.4), 양안간격(HI=44.8)의 4가지 형질은 한강납줄개와 떡납줄갱이의 중간형질을 나타내는 것으로 나타났다. 나머지 14가지 형질은 0과 100 사이를 벗어나 잡종개체만의 고유한 특성을 나타냈다. Recombination activating gene 1 (RAG1) 분석결과 잡종개체는 부모종의 유전자가 중복되어 나타나 자연잡종으로 판별되었으며, cytochrome b gene (COB)를 분석한 결과 한 개체는 한강납줄개를 모계로, 또 다른 한 개체는 떡납줄갱이가 모계로 나타났다.

Antitumor Activities of Sea Staghorn (Codium fragile) against CT-26 Cells

  • Kim, Kil-Nam;Kim, Soo-Hyun;Kim, Won-Suk;Kang, Sung-Myung;Lee, Ki-Wan;Lee, Wook-Jae;Park, Soo-Yeong;Kim, Se-Kwon;Jeon, You-Jin
    • Food Science and Biotechnology
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    • 제17권5호
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    • pp.976-982
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    • 2008
  • The 10 species of marine green algae was collected from Jejudo(Island) in Korea. Methanolic and aqueous extracts were prepared and screened for inhibition activities against tumor cell growth. Of the tested samples, the sea staghorn (Codium fragile) aqueous extract (CFAE) showed the highest activity on CT-26 cell growth. Therefore, CFAE was selected for further experiments and the possibility to induce apoptosis by the CFAE was investigated. Flow cytometric analysis revealed that it dose-dependently increased apoptotic cells with hypodiploid DNA contents in CT-26 cell line. These results indicated that CFAE can suppress the growth of CT-26 cells through apoptosis. The CFAE decreased the protein expression of anti-apoptotic Bcl-xL and led to the activation of caspase-3 and -7. A crude polysaccharide was separated from CFAE and it mainly constituted with 61.2% galactose and 30.5% arabinose as analyzed by high performance liquid chromatography (HPLC).

주행중 차고 조절이 가능한 유압식 현가장치 개발 및 진동특성 비교 분석 (The development of hydraulic suspension system capable of vehicle height at driving and the comparative analysis of vibration characteristic)

  • 강형선;백종진
    • 한국산학기술학회논문지
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    • 제14권2호
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    • pp.561-566
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    • 2013
  • 본 연구는 유압식 자동차고 조절장치 개발 및 상기장치를 일반 상용차에 적용시키기 위한 것이다. 운전자의 승차감에 영향을 줄 진동특성을 주행시험을 통하여 파악하고자 하였다. 유압식 자동차고 조절장치는 현재 승용차에 가장 많이 사용되고 있는 맥퍼슨 형식의 형태로 설계되었다. 맥퍼슨 형식의 순정현가장치, 튜닝현가장치, 유압식 자동차고 조절장치를 장착한 차량으로 시험을 수행하였다. 자동차에 전달되는 진동특성은 랜덤형태이므로 PSD(Power Spectrum Density)값을 비교하였다.

Enhancement of $\beta$-D-Glucans Production by Agaricus blazei Murill by Nitrogen Supplementation

  • NA JEONG-GEOL;KIM HYUN-HAN;CHUN GIE-TAEK;CHANG YONG KEUN;LEE SANG JONG;CHUNG YEON HO
    • Journal of Microbiology and Biotechnology
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    • 제15권6호
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    • pp.1388-1391
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    • 2005
  • Temporal changes of cell growth pattern and intracellular content of $\beta$-D-glucans were investigated with off-gas data in Agaricus blazei culture where glucose was intermittently fed. It was observed that the time point of carbon source depletion coincided with the point of sudden drop in the carbon dioxide evolution rate (CER), and that the sole supplementation of glucose was not enough to maintain active cell growth and glucan content. On the other hand, when yeast extract, a typical nitrogen source, was supplemented together with glucose when the CER suddenly dropped because of carbon source depletion, an active cell growth could be maintained until the end of the culture and the glucan content did not decrease with culture time, significantly enhancing glucan productivity.

디레이팅 기법에 의한 마이크로 퓨즈 용단의 특성 분석 (Character Analysis of Micro Fuse Fusing as a function of De-Rating technique)

  • 김도경;김종식
    • 조명전기설비학회논문지
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    • 제29권6호
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    • pp.8-13
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    • 2015
  • Recently, Illumination industry of LED module has been focused to industry technology for energy conservation of nation. The LED device is excellent to power efficiency due to semiconductor light source element. And the application to the lighting circuit technology can be designed to the sensitive lighting system for human sensitivity control. In this paper, as a process for analyzing the operating temperature of standardized electronic device including LED device has analyzed about fusing character with in designed micro fuse for electronic device protection from the over current. Using the de-rating technique, which is performed to micro fuse fusing test in the range of $-30^{\circ}C{\sim}120^{\circ}C$ thermostatic chamber. To the output data in each temperature zone, it is performed to first-order linear fitting. Additionally, applying the resistance temperature coefficient and statistical data for the reliable analysis has derived to the metal element resistance of micro fuse with temperature change of the thermostatic chamber. As a research result, The changed temperature effect of thermostatic chamber was confirmed regarding fusing time change.

Aerodynamic loads and aeroelastic responses of large wind turbine tower-blade coupled structure in yaw condition

  • Ke, S.T.;Wang, T.G.;Ge, Y.J.;Tamura, Y.
    • Structural Engineering and Mechanics
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    • 제56권6호
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    • pp.1021-1040
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    • 2015
  • An effective method to calculate aerodynamic loads and aeroelastic responses of large wind turbine tower-blade coupled structures in yaw condition is proposed. By a case study on a 5 MW large wind turbine, the finite element model of the wind turbine tower-blade coupled structure is established to obtain the modal information. The harmonic superposition method and modified blade-element momentum theory are used to calculate aerodynamic loads in yaw condition, in which the wind shear, tower shadow, tower-blade modal and aerodynamic interactions, and rotational effects are fully taken into account. The mode superposition method is used to calculate kinetic equation of wind turbine tower-blade coupled structure in time domain. The induced velocity and dynamic loads are updated through iterative loop, and the aeroelastic responses of large wind turbine tower-blade coupled system are then obtained. For completeness, the yaw effect and aeroelastic effect on aerodynamic loads and wind-induced responses are discussed in detail based on the calculating results.

연삭 휠 형상 복합가공시스템의 구조 안전성에 관한 연구 (A Study on Structural Safety of Integrated Machine for Grinding Wheel Forming)

  • 이원석;안범상;김진현;이종찬;우봉근;이영식
    • 한국기계가공학회지
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    • 제15권2호
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    • pp.84-88
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    • 2016
  • This study evaluated the structural safety of a heavy-duty integrated machine for grinding wheel forming. Structural analysis was performed to evaluate the structural safety of the base. The base was designed by dividing the single base and detachable base. The analysis conditions were applied to the own weight and the load of component parts. From the structural analysis results, although the stress of the detachable base was decreased, the amount of deformation was increased. If the deformation of the detachable base decreases, it is expected to be safer than the single base.

다기능 자동 선반 베드의 고강성 구조설계에 관한 연구 (Study on Structure Design of High-Stiffness for Multi-Function Automatic Lathe Bed)

  • 조은정;이윤철;안종복;이영식;이재권;김광선
    • 반도체디스플레이기술학회지
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    • 제18권1호
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    • pp.112-116
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    • 2019
  • This study was carried out by structural analysis using finite element method for designing high rigidity structure of multi - functional automatic lathe bed. As a result of comparison, it was confirmed that the weight was designed to be higher than the maximum deformation amount. The shape and dimensions of the main pillars and walls of the bed were changed to derive the most suitable design for the multifunction automatic lathe bed. A model of structural design was derived with the goal of minimizing the maximum deformation amount of $20{\mu}m$ or less and the weight of the bed. As a result of applying the derived design improvement proposal to the multifunctional automatic lathe bed, 57.4% weight reduction and maximum principal stress decreased by 45.0% than the initial design model. It is expected that the optimum design that meets these design conditions will reduce the weight of the structure as well as improve the safety of the structure and reduce the machining error in the operation of the machine tool.

Emodin Attenuates Inflammasome Activation Induced by Helicobacter pylori Infection through Inhibition of VacA Translocation

  • Thach Phan Van;Anh Duy Do
    • 한국미생물·생명공학회지
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    • 제51권4호
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    • pp.507-516
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    • 2023
  • Eradication of Helicobacter pylori infection is an essential strategy to decrease the risk of developing gastric cancer. However, the standard triple therapy has negative aspects associated with side effects and the emergence of antibiotic resistance. Therefore, alternative therapies are required to enhance the management of H. pylori infection effectively. In this study we examined the effect of emodin on the amelioration of inflammatory response due to H. pylori infection. Our results indicated that emodin treatment effectively decreased the expression of virulence genes, including sabA, vacA, cagL, cagA, sabA, and suppressed the adhesion ability of H. pylori to AGS cells. Emodin has been shown inhibitory effects on the inflammasome pathway through reductions in VacA translocation, lowering ROS stress, cleaved Caspase-1, NLRP3, and cleaved Gasdermin D levels, thereby lowered pyroptosis in infected cells. In summary, our study demonstrated that emodin has the ability to attenuate inflammation caused by H. pylori by modulating virulence gene expression and decreasing VacA translocation. Further study is required to evaluate the therapeutic efficacy of emodin in treating H. pylori infection and better understand the underlying mechanisms.