• 제목/요약/키워드: shade treatment

검색결과 148건 처리시간 0.037초

Light Intensity Influences Photosynthesis and Crop Characteristics of Jeffersonia dubia

  • Rhie, Yong Ha;Lee, Seung Youn;Jung, Hyun Hwan;Kim, Ki Sun
    • 원예과학기술지
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    • 제32권5호
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    • pp.584-589
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    • 2014
  • Jeffersonia dubia is a spring-flowering perennial found in rich forests in Korea and Northern China and has potential as an ornamental or medicinal plant. However, illegal picking and land use change have decreased the number of populations and overall population size of this plant in its natural habitat. Although J. dubia has been reported to be a shade-preferring plant, no study has determined the optimum light intensity for its growth. The objectives of this work were to observe the effects of various shading levels on the physiological responses of J. dubia and to determine the proper shading level for cultivation. Treatments consisted of four shading levels (0%, 50%, 75%, and 95% shade) imposed using black mesh cloth. The number of leaves and dry weight increased with decreased shading. The shoot-to-root ratio increased with increased shading, mainly due to decreased root dry weight under shading. Plants showed low net $CO_2$ assimilation rates and $F_v/F_m$ values combined with low dry matter levels when grown under 0% shade (full sunlight). These results indicate that J. dubia plants experience excessive irradiance without shading, resulting in damage to the photosynthetic apparatus. By contrast, the net photosynthesis rate increased as the shading level increased. $F_v/F_m$, the potential efficiency of PSII, was 0.8 under 95% shade, indicating that J. dubia is well-adapted under heavy shading. However, the low dry matter of plants in the 95% shade treatment indicated that the low light intensity under 95% shade led to a decline in plant growth. Thus, moderate light (50% shading) is recommended for cultivating J. dubia without physiological defects.

인삼의 생육시기와 재식위치에 따른 엽록소 형광반응 및 광합성 특성 (Effects of Chlorophyll Fluorescence and Photosynthesis Characteristics by Planting Positions and Growth Stage in Panax ginseng C. A. Meyer)

  • 오동주;이충열;김성만;이관영;이수지;황대연;손홍주;원준연
    • 한국약용작물학회지
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    • 제18권2호
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    • pp.65-69
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    • 2010
  • As cool-season plant, Panax ginseng C. A. Meyer is planted under shade-installation with tall front and low rear. However, at different planting positions, distinct differences come out because ginseng grows at the same position within 3~5 years and the growth circumstance changes a lot by the shade-installation. So, in this study, changes of temperature, photosynthesis and chlorophyll fluorescence with varieties of shading material and planting position were investigated. Light transmittances by polyethylene shade net and silver-coated shading plate as planting materials were measured according to different planting positions. Photosynthetic rate and chlorophyll fluorescence were measured by LI-6400-40 (Li-Cor). According to different planting positions, light intensity was higher in silver-coated shading plate than in polyethylene shade net, and higher at front than rear. Also, photosynthetic rate showed the same tendency, which had a positive correlation to light intensity. But this treatment caused a lower Fo compared with polyethylene shade net because of the stress by light and temperature. Also, Fv/Fm and ETR were higher in silver-coated shading plate. Fo was similar at front and rear according to silver-coated shading plate and ETR was higher at front.

배지조성과 차광정도가 시설하우스 재배 인삼의 초기 생육 및 생리활성에 미치는 영향 (Effects of Shading Degree and Substrate Component on Early Growth and Physiological Activity of Panax ginseng Grown under Plastic House)

  • 천상욱;정순목
    • 한국자원식물학회지
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    • 제24권5호
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    • pp.613-621
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    • 2011
  • 인삼의 시설생산을 위하여 배지 조성 및 차광 정도를 달리한 환경조건 하에서의 생육특성과 생리활성 변화를 검토하고자 온실 및 실내시험을 수행하였다. 적정한 배지 조합은 차광 정도에 따라 달랐는데 무차광에서는 coco peat 단독, 50% 차광에서는 coco peat와 perlite를 50:50으로 혼합하였을 때, 70% 차광에서는 perlite 단독배지에서 유의적으로 높은 생육을 보였다(P<0.05). 차광은 엽면적, 엽록소 함량, 근장, 지상부 및 지하부 생체중을 유의적으로 감소시켰다. 총 페놀 함량은 지상부(20.7~23.8 $mg{\cdot}kg^{-1}$)보다는 지하부(25.8~28.4 $mg{\cdot}kg^{-1}$)에서, 무차광(20.7~25.8 $mg{\cdot}kg^{-1}$)보다는 차광(23.7~28.4 $mg{\cdot}kg^{-1}$)에서 높게 나타났다. 총 플라보노이드 함량은 지하부(6.9~7.0 $mg{\cdot}kg^{-1}$)보다는 지상부에서(17.4~26.8 $mg{\cdot}kg^{-1}$), 무차광보다는 차광에서 높게 검출되었다. 반면, DPPH 라디컬 소거능 측정을 통한 항산화성은 추출물 농도가 증가할수록 높은 활성을 보였고, 지하부(24.9~28.7%)보다는 지상부에서(31.1~36.5%), 차광보다는 무차광에서 다소 높은 활성을 보였다. 결론적으로 차광은 비닐하우스 조건하에서 재배된 인삼의 생육과 생리활성에 영향을 미치는 것으로 나타났다.

차광이 반지형 잔디의 여름철 하고현상 감소에 미치는 영향 (The Effect of Shade Net on Summer Stress of Cool-season Turfgrass)

  • 이재필;김석정;서한용;이상재;김태준;김두환
    • 아시안잔디학회지
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    • 제15권2호
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    • pp.51-64
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    • 2001
  • 본 연구는 우리나라 여름철 고온다습 환경 하에서 축구장에 조성된 한지형 잔디의 하고현상을 줄이기 위해 차광이 한지형 잔디의 하고현상을 감소에 미치는 영향을 구명하고자 하였다. 1999년 5월부터 2001년 8원까지 35% tall fescue+50% kentucky bluegrass+15% perennial ryegrass의 한지형 잔디로 조성된 건국대 포장에서 실험되었다. 한지형 잔디의 여름철 하고현상 피해를 감소시키기 위해 차광률(0, 50%, 75%), 차광색(검정, 녹색), 차광 높이(잔디면 0cm 위, 잔디면 30cm위) 및 차광시간(오전 10시부터 5시가지 7시간만 차광, 24시간 차광)을 달리하여 처리하였다. 차광처리는 1999년 6월8일부터 매년 여름 기간 동안 차광하였고 실험구의 크기는 1.25m$\times$3m이며 3반복 완전임의 배치하였다. 대조구 온도가 30~35$^{\circ}C$일 때 처리구간의 잔디표면 온도 차이는 2~3$^{\circ}C$로 적었지만 4$0^{\circ}C$ 이상의 고온에서는 차광처리구가 대조구에 비해 6~13$^{\circ}C$ 정도 낮았으며, 검정차광이 녹색차광보다 온도를 더 낮추었다. 맑은 날 조도는 대조구가 66,700~95,200 Lux인 데 비해 50%와 75% 검정차광처리구는 대조구보다 40~94% 정도로 지나치게 차광되었다. 반면 50%와 75% 녹색차광처리구는 25~54%의 차광률을 보여 검정보다 녹색 차광막의 차광률이 낮게 나타나 한지형 잔디의 광합성 측면에서 볼 때 녹색이 더 효과적일 것으로 판단된다. 차광률 및 차광색은 50%와 75%의 녹색 차광처리구에서 엽색, 잔디면 품질, 예지물량과 지하부 건물중이 우수하였다. 반면 75% 검정색 차광처리구는 한지형 잔디를 심하게 도장시켰으려 그 후 고온과 과습은 한지형 잔디를 갈변 후 부패시켰다. 50% 검정 차광막으고 차광높이를 달리한 실험에서 잔디면 바로 위에 덮은 처리구는 장마 후 고온으로 한지형 잔디를 각변 후 부패시켰지만 30cm 높이로 띄운 처리구에서는 하고현상의 피해가 적었다. 타광시간에 있어 50% 검정 차광막으로 30cm 높이로 24시간 차광처리구와 0cm 높이로 오전 10시부터 5시까지 7시간 차광 처리구에서 한지형 잔디의 엽색, 잔디면 품질, 예지물 및 지하부 건물중의 차이가 적게 나타났다. 이상을 요약하면 50%와 75% 녹색착광막을 우리나라 여름철 장마기 중 강한 햇볕으로 잔디 표면 온도가 갑자기 상승하거나 경기장 이용 후 한지형 잔디를 회복시키고자 할 때 오전 10시부터 5시까지 차광을 지속하변 한지형 잔디 지상부 및 지하부의 생육을 유지 또는 촉진하며 하고현상감소를 위한 관리적 방법으로 사용될 수 있을 것으고 판단된다. 그러나 녹색타괌만은 검정차광막보다 온도를 낮추는 효과가 적어 온도를 6~13$^{\circ}C$로 낮추고 조도를 50,000~60,000만 Lux를 유지할 수 있는 녹색+검정색이 혼합된 차광막에 대한 연구가 지속되어야 할 것으로 판단된다.

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An Evaluation of the Repetitive Tooth Bleaching with Nonthermal Atmospheric Pressure Plasma

  • Nam, Seoul Hee;Kim, Gyoo Cheon;Hong, Jin Woo
    • International Journal of Oral Biology
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    • 제41권4호
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    • pp.243-251
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    • 2016
  • This study was undertaken to achieve a high bleaching efficacy with plasma, through longer application and reparative bleaching processes, by different shade evaluation methods. Extracted human teeth were divided into 6 groups (n=10). All teeth were treated in pairs. Low concentration of 15% carbamide peroxide (CP) was applied, with and without plasma, for 10, 20, and 30-min tooth bleaching, respectively. The bleaching procedure was repeated once daily for four days. The teeth were maintained in a moist environment provided by artificial saliva. The Vitapan Classical shade guide and Commission Internationale de L'Eclairage (CIELAB) color system were collectively used to measure the bleaching efficacy. Color evaluation was statistically analyzed using Student t-test and one-way analysis of variance (ANOVA) complemented by Tukey's test. Combining the plasma with 15% CP showed significantly greater color changes compared to bleaching without plasma (p<0.05). A high bleaching efficacy with plasma is proportional to the repetitive application and the treatment time. A 30-min application with plasma provided the best bleaching. Repetitive bleaching showed lower probability of color relapse of the bleached tooth. The color change by shade guide correlated with the changes in CIELAB color system. A value of 1 color change units (CCU) conversion factor for overall color change (${\Delta}E$) values comparisons was 3.724 values. The two measuring methods provide a more accurate correspondence of color change. The repetitive and longer application for tooth bleaching, combined with plasma, has a strong bleaching effect and produces whiter teeth.

Effects of Larval Extracts from P. brevitarsis seulensison Cytokine and Diagnostic Marker in Carbon Tetrachloride-Administered SD Rats

  • Lee, Ji-Sook;Kwon, Ohseok;Hwang, Seock-Yeon;Yun, Chi-Young
    • 대한임상검사과학회지
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    • 제43권3호
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    • pp.113-119
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    • 2011
  • This study was designed to determine the effects of larval extracts from Protaetia brevitarsis seulensis shade dried larva from Korea and China on liver tissues of hepatic injury groups. The experimental groups are divided into five groups; Normal, carbon tetrachloride single injection ($CCl_4$), Pb-CHI ($CCl_4$ + P. brevitarsis shade dried larva from China), Pb-KOR ($CCl_4$ + P. brevitarsis shade dried larva from Korea) and SIL ($CCl_4$ + 0.35% silymarin) groups. Sprague Dawley rats were oral injected with $CCl_4$ at a dose l mg/kg (20% in corn oil) for induction of liver damage for 4 weeks. Each experimental group was fed with a dose 50 mg/kg of larval extracts based on medicinal preparations from 3 weeks to 4 weeks after $CCl_4$ treatment. At the end of 4 weeks, we evaluated the serum levels of glutamate-oxaloacetate transaminase (GOT), glutamate-pyruvate transferase (GPT), alkaline phosphatase (ALP) and blood urea nitrogen (BUN) in serum and the cytokine levels of tumor necrosis factor-${\alpha}$) (TNF-${\alpha}$) and transforming growth factor-${\beta}$ (TGF-${\beta}$) in the cells isolated from spleen and liver. The histological analysis was also conducted. The $CCl_4$ injection reduced body weight, induced congestion of middle lobe and hepatocytic degeneration, resulting in disintegration of hepatic cords, and increased biochemical markers of blood related to hepatic injury. On the other hand, the Pb-CHI and Pb-KOR group decreased the levels of biochemical markers in blood and cytokine levels in spleen and liver. Especially, the Pb-KOR group facilitated the recovery of biochemical values of blood related to hepatic injury, hepatic lesions and fibrosis. Taken together, larval extract from P. brevitarsis might prevent acute hepatotoxicity and enhance the recovery of liver fibrosis and cirrhosis induced by $CCl_4$, and the ingredients could be a promising candidate for the prevention and treatment of hepatic disorders.

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Effects on Net Photosynthesis in Field-Grown Hot Peppers Responding to the Increased CO2 and Temperature

  • Yun, Sung-Chul;Ahn, Mun-Il
    • 한국환경농학회지
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    • 제28권2호
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    • pp.106-112
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    • 2009
  • The increased $CO_2$ and temperature (700 ${\mu}$mol.$mol^{-1}$ $CO_2$ and $30^{\circ}C$) was compared with ambient growth conditions (400 ${\mu}$mol.$mol^{-1}$ $CO_2$ and $25^{\circ}C$) in hot pepper. Gas exchange measurements, including net photosynthesis ($P_{net}$) and stomatal conductance ($g_s$), were taken according to treatment in fields of peppers grown in Suwon and Asan during 2008. The increased treatment $P_{net}$ by 35-45% throughout the season and was statistically significant in t-tests (p < 0.001); however, it did not significantly affect $g_s$. In addition, the gas exchange parameters in sun and shade leaves were measured. The difference between the sun and shade leaves was much greater than that between the elevated and ambient treatments, especially at harvest. Four commercial cultivars of hot pepper, Chunhasangsa, Ryukang, Manitta, and Olympic, were also compared by ANOVA. Chunhasangsa had the highest $P_{net}$, which decreased by 30% from the vegetative to the harvest stage. Based on a factorial design, the effect of the increased $CO_2$ and temperature was assessed based on the temperature, $CO_2$, and their interaction effects. Orthogonal contrasts showed that the effects of temperature on $P_{net}$ and $g_s$ were significant, whereas $CO_2$ and their interactions were not.

How will surface treatments affect the translucency of porcelain laminate veneers?

  • Turgut, Sedanur;Bagis, Bora;Ayaz, Elif Aydogan;Korkmaz, Fatih Mehmet;Ulusoy, Kivanc Utku;Bagis, Yildirim Hakan
    • The Journal of Advanced Prosthodontics
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    • 제6권1호
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    • pp.8-13
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    • 2014
  • PURPOSE. The purpose of this study was to evaluate whether surface treatments affect the translucency of laminate veneers with different shades and thicknesses. MATERIALS AND METHODS. A total of 224 disc-shaped ceramic veneers were prepared from A1, A3, HT (High Translucent) and HO (High Opaque) shades of IPS e.max Press (Ivoclar Vivadent) with 0.5 mm and 1.0 mm thicknesses. The ceramics were divided into four groups for surface treatments. Group C: no surface treatments; Group HF: etched with hydrofluoric acid; Group SB: sandblasted with 50-${\mu}m$ $Al_2O_3$; and Group L; irradiated with an Er;YAG laser. A translucent shade of resin cement (Rely X Veneer, 3M ESPE) was chosen for cementation. The color values of the veneers were measured with a colorimeter and translucency parameter (TP) values were calculated. A three-way ANOVA with interactions for TP values was performed and Bonferroni tests were used when appropriate (${\alpha}=0.05$). RESULTS. There were significant interactions between the surface treatments, ceramic shades and thicknesses (P=.001). For the 0.5-mm-thick specimens there were significant differences after the SB and L treatments. There was no significant difference between the HF and C treatments for any shades or thicknesses (P>.05). For the 1-mm-thick ceramics, there was only a significant difference between the L and C treatments for the HT shade ceramics (P=.01). There were also significant differences between the SB and C treatments except not for the HO shades (P=.768). CONCLUSION. The SB and L treatments caused laminate veneers to become more opaque; however, HF treatment did not affect the TP values. When the laminate veneers were thinner, both the shade of the ceramic and the SB and laser treatments had a greater effect on the TP values.

광도 저하에 대한 5개 활엽수의 생리적 응답 반응 (Physiological Responses of the Five Deciduous Hardwood Seedlings Growing Under Different Shade Treatments)

  • 조민석;권기원;김길남;김판기
    • 한국산림과학회지
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    • 제97권6호
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    • pp.680-689
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    • 2008
  • 본 연구에서는 층층나무, 물푸레나무, 박달나무, 개벚나무, 고로쇠나무를 대상으로 차광처리를 통해 4가지 수준(상대 차광률; 전광처리구, 전광대비 65~72%, 29~40%, 7~12%)으로 광도 조건을 달리하여 광합성 특성을 조사하였다. 그 결과, 층층나무, 물푸레나무 및 박달나무는 차광처리에 의하여 광합성 능력과 엽록소 형광이 저하하여, 내음성 수준이 낮음을 시사하였다. 개벚나무는 조사 시기별 차이는 있었으나, 강피음 처리구를 제외한 나머지 세 처리구에서 좋은 광합성 능력을 나타내, 보통 수준의 내음성을 보였다. 한편 고로쇠나무는 전광대비 29~40% 처리구에서 가장 높은 광합성 능력과 엽록소 형광을 나타내, 내음성 수준이 공시수종 중에 가장 높음을 시사하였다.

디지털 프린팅 견직물의 색상 변화 및 견뢰도 - 혼합 전처리제의 영향 (Color Fastness of Digital Textile Printing on Silk Fabrics - The effect of the mixed pre-treatment agent)

  • 정동석;천태일
    • 한국의류산업학회지
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    • 제15권5호
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    • pp.808-814
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    • 2013
  • In this study, The mixture of three kinds of pre-treatment agents, Carboxymethyl cellulose sodium salt(CMC), Sodium alginate and Dextrin, have been prepared for the better coloration of digital textile printing. To get sharpness of outline during digital printing process, the optimal formulation is the CMC and Sodium alginate mixture 1:1 ratio by volume. Cyan, Yellow, and Black colours are excellent on the Sodium alginate mixtures. But, Magenta is excellent in the CMC and Dextrin mixture. Sharpness and printability are closely related to viscosity of the mixture. The most optimal sharpness of outline achieved with a consideration of coloring, and field operations account for production when the viscosity of the mixed pre-treatment agent approximately is 10~13 cSt. Change in shade and staining of wash fastness for all the treated samples with the mixtures rated 4-5 grade. Both dry rubbing fastness to shade change and staining are good in the treated samples, whereas wet rubbing fastness rated 2-3 grade. To improve wet rubbing fastness, the Sodium alginate and Dextrine mixture, which rated 3-4 grade for Black color, is applicable. With exception of 3 rating to black color, Light fastness is 4 rating for the remaining three colors in the regardless of treatment condition and mixing of the pre-treatment agent. Dry cleaning fastness of all samples are also 4-5 rating.