• 제목/요약/키워드: Photo-activity

검색결과 218건 처리시간 0.028초

A dominant negative OsKAT2 mutant delays light-induced stomatal opening and improves drought tolerance without yield penalty in rice

  • Kim, Jin-Ae;Moon, Seok-Jun;Lee, Yongsang;Min, Myung Ki;Yoon, In sun;Kwon, Taek-Ryoun;Kim, Beom-Gi
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.110-110
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    • 2017
  • Stomata are the main gateways for water and air transport between leaves and the environment. Inward-rectifying potassium channels regulate photo-induced stomatal opening. Rice contains three inward rectifying shaker-like potassium channel proteins, OsKAT1, OsKAT2 and OsKAT3. Among these, only OsKAT2 is specifically expressed in guard cells. Here, we investigated the functions of OsKAT2 in stomatal regulation using three dominant negative mutant proteins, OsKAT2(T235R), OsKAT2(T285A) and OsKAT2(T285D), which are altered in amino acids in the channel pore and at a phosphorylation site. Yeast complementation and patch clamp assays showed that all three mutant proteins lost channel activity. However, among plants overexpressing these mutant proteins, only plants overexpressing OsKAT2(T235R) showed significantly less water loss than the control. Moreover, overexpression of this mutant protein led to delayed photo-induced stomatal opening and increased drought tolerance. Our results indicate that OsKAT2 is an inward-rectifying shaker-like potassium channel that mainly functions in stomatal opening. Interestingly, overexpression of OsKAT2(T235R) did not cause serious defects in growth or yield in rice, suggesting that OsKAT2 is a potential target for engineering plants with improved drought tolerance without yield penalty.

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Photo-protective and Anti-melanogenic Effect from Phenolic Compound of Olive Leaf (Olea europaea L. var. Kalamata) Extracts on the Immortalized Human Keratinocytes and B16F1 Melanoma Cells

  • Ha, Ju-Yeon;Choi, Hyun-Kyung;Oh, Myoung-Jin;Choi, Hae-Yeon;Park, Chang-Seo;Shin, Han-Seung
    • Food Science and Biotechnology
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    • 제18권5호
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    • pp.1193-1198
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    • 2009
  • Ethylacetate and butanol fractions of leaf extracts (OLE) showed the higher contents of total phenolic compounds than hexane and water fractions. Oleuropein contents were $4.21{\pm}0.57,\;3.92{\pm}0.43,\;0.32{\pm}0.03,\;5.76{\pm}0.32$, and $32.47{\pm}0.25mg$/100g for ethanol extract, and hexane, chloroform, ethyl acetate, and butanol fraction, respectively. Treatment of ultraviolet-B (UVB) irradiated cells with 3 OLEs prepared by using ethylacetate and butanol at concentrations 0.001, 0.005, and 0.01% respectively showed significant recovery of cell viabilities. Treatment of dexametason 1 mM reduced tumor necrotic factor (TNF)-${\alpha}$ secretion by about 40%. UVB irradiated immortalized human keratinocytes (HaCaT) cells were treated with 3 different OLEs at the same concentrations. Ethylacetate fraction showed the strongest inhibition activity with respect of reduction of the elevated (TNF)-${\alpha}$. Cytotoxicity of OLEs on the B16-F1 cells was evaluated through thiazolyl blue tetrazolium bromide (MTT) assay. Ethylacetate fraction has no cytotoxicity in the range of 0.005-0.01%. A slight cytotoxicity was observed at the concentration of 0.1% butanol fraction of OLE that caused 10% decrease in cell viability.

Photoimmunological and Photobiological Action of Infrared Radiation

  • Danno, Kiichiro
    • Journal of Photoscience
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    • 제9권2호
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    • pp.194-196
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    • 2002
  • While ultraviolet radiation alters various cutaneous cell functions, little is known about photo-immunological and photobiological effects of infrared radiation (IR) on the skin except its local thermal effects. The fIrst part of this study demonstrated that single exposure of mouse skin to near IR (0.7 - 1.3 $\mu$m) reversibly suppressed the proliferating activity of the epidermis, the density of Langerhans cells, and the ability of skin to induce contact hypersensitivity reaction. The second part demonstrated that the rate of wound closure was significantly accelerated by repeated exposures in animal models. The production of transforming growth factor-$\beta$l and matrix metalloproteinase-2, which are responsible for the wound healing processes, was significantly upregulated by irradiation, as shown by enzyme immunoassay, zymography, and reverse transcription polymerase chain reaction. Thermal controls were negative. The results suggest that near-IR irradiation can modulate the epidermal proliferation and part of the skin immune system, and stimulate the wound healing processes, presumably by non-thermal effects.

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WWW에 기반한 부동산 거래 정보 관리 시스템 설계 및 구현 (Design and Implementation of Realty Trade Information Management System based on WWW)

  • 권석형;김명선;김양희;정창성
    • Spatial Information Research
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    • 제4권1호
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    • pp.75-81
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    • 1996
  • 부동산 거래 관리 시스템이란 부동산 거래 관리 활동과 관련된 등록, 검색, 상담 및 부동산에 대한 이력 관리와 분석을 목적으로 하는 시스템이다. 거래 상담 및 분석 과정에서 부동산에 대한 지형 정보 서비스가 지대한 영향을 미친다. 본 시스템은 지도 정보 및 비디오나 사진등과 같은 영상 정보를 포괄하는 지형 정보 서비스를 제공함으로써, 원격지 거래자들간의 상담 및 관리/분석 활동이 원활히 이루어질 수 있도록 설계/구현되었다. 또한, WWW를 통해 이같은 지형 정보 서비스를 제공함으로써 사용자들이 별도의 클라이언트 에뮬레이터 없이 다양한 멀티미디어 서비스를 받을 수 있도록 설계/구현 되었다.

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MAGNETIC HELICITY OF SOLAR ACTIVE REGIONS AND ITS IMPLICATIONS

  • SAKURAI T.;HAGINO M.
    • 천문학회지
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    • 제36권spc1호
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    • pp.7-12
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    • 2003
  • We have studied the magnetic helicity of active regions by using the data from (1) the photo-electric magnetograph of the Okayama Observatory (1983-1995) and (2) the video magnetograph of NAOJ/Mitaka (1992-2000). The latitude distribution of helicity showed a tendency that the regions in the north (south) hemisphere have negative (positive) helicities, respectively, which is already known as the hemispheric sign rule. If we look into the sign of helicity as a function of time, the sign rule was less definite or was reversed sometimes in the sunspot minimum phase. We also studied the relation between the magnetic helicity and the sunspot tilt angles, and found that these two quantities are positively correlated, which is opposite to the expectation of a theoretical model. The implications of this cycle-phase dependence of helicity signs and the correlation between magnetic he Ii city and sunspot tilt angles are discussed.

Development of a hazard map creation support system with community participation type using positional information

  • Mori, Seina;Okazaki, Yasuhisa;Wakuya, Hiroshi;Mishima, Nobuo;Hayashida, Yukuo;Min, Byung-Won
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2015년도 춘계 종합학술대회 논문집
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    • pp.11-12
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    • 2015
  • This paper describes development of a system that can create a hazard map by residents in order to prepare for disaster in daily life. This system make a hazard map by displaying the community-based disaster information on the map. Residents register information about the spot (a disaster type, a risk level, a photo, comments, positional information) that can be dangerous in case disaster. We think that residents can share information while having fan and increase disaster prevention consciousness by resident participation activities.

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Fundamental Study on the Photocatalytic Degradation of Organics in Industrial Waste Water with the Presence of Titanium Dioxide

  • Kusaka, Eishi;Izawa, Mihiro;Fukunaka, Yasuhiro;Ishii, Ryuji
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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    • pp.286-291
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    • 2001
  • As part of fundamental studies on the degradation of the organic compounds in industrial waste water, the photocatalytic degradation properties of the organic compound by means of the UV/TiO$_2$degradation process have been investigated. The test organic compound of acetic acid was chosen in this study. The testing of photo catalytic degradation were performed under various operation conditions such as TiO$_2$dosages, initial concentration of the organic, the aqueous pH's, etc. The effects of various parameters on the short time activity of the present acetic acid-UV/TiO$_2$system could be demonstrated from this investigation.

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광촉매 반응치 설계를 위한 기초 연구 (A Fundamental Study for a Photocatalytic Reactor Design)

  • 손건석;윤승원;고성혁;김대중;송재원;이귀영
    • 한국자동차공학회논문집
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    • 제10권2호
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    • pp.40-47
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    • 2002
  • Because UV wavelength lights can activate photocatalysts, plasma is used as a light source of a photocatalytic reactor. Even though plasma has good intensity for photo reaction, substrate of catalyst coating was limited by the geometry of plasma generator. Usually bead type substrate was used for a pack bed type reactor. Honeycomb monolith type substrate was used with UV lamps instead plasma, due to the light penetration the honeycomb monolith length was too short to show good activity In this study a photocatalytic reactor, which is using a honeycomb monolith substrate, was investigated with plasma as an activation light source. As a parametric study the effects of 1311owing factors on plasma generation and power consumption are examined; supply voltage, substrate length, environment condition, catalyst loading and ratio. Using the test results, the practicability test was done with simulated synthetic gases representing bad smells and automotive exhaust gases.

Effect of photosensitizer aganist anti-red tide substances from korea seaweed extracts

  • Jin, Hyung-joo;Jin, Long-Guo;Hong, Sung-Youl;Hong, Yong-Ki
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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    • pp.153-154
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    • 2000
  • Many bioactive photosensitizers have been isolated from plants and some of theses possess antiviral activities which, depend on UVA(320-400nm) and visible light. Many complex quinonoids have been isolated from plants and recently some of them, such as hypericin and hypocrellin, have been shown to possess light-dependent antiviral activities. these compounds only exert their desired biological activities in the presence of long wavelength ultra-violet UVA but these activities are also strongly influenced b chemical structure(Hudson et al, 1995). the importance of light in the use of certain medicinal plant extracts has been appreciated, if not understood, for centuries. Also, many seaweed extracts will effect photo(UVA, visible light) for algicidal activity. (omitted)

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광촉매를 이용한 광촉매 성능 측정 표준화의 이해 (Standard test method for photo- catalytic activity with optical fiber)

  • 주현규;하진욱;조덕호
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2005년도 춘계학술발표논문집
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    • pp.312-314
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    • 2005
  • 최근 일본이 광촉매 관련 제품에서의 소비자. 보호를 위한 적절한 표준화 규격 제정에 강한 의욕을 보이며, 자국내 JIS 규격 외에 ISO 규격 (ISO/TC 206 fine ceramics)을 제정하기 위하여 노력하고 있다. 이에 국내에서는 산업보호 및 해외시장에서의 종속성을 벗어나기 위하여 2001년부터 선정된 분야에서의 광촉매표준화 시도가 이루어졌다. 그 중의 하나로 본 논문은 광섬유를 빛 전달 매개체와 광촉매 코팅 지지체로 이용해서 광촉매 졸을 구성하는 광촉매 자체의 유기물 분해능을 결정하는 방법을 규정하는 과정과 제안과 관련된 것이다. 이 규격은 코팅 가능한 졸이나 졸로 만들 수 있는 자외선 감응 광촉매 재료에 적용하며, 차후 가시광 및 태양광 감응 광촉매 활성 측정 및 비교에도 응용이 가능할 것으로 판단된다.

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