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Effect of Heat Treatment on the Lipophillic Pigments of Fresh Green Tea Liquor

  • Lu, Jian-Liang;Dong, Zhan-Bo;Pan, Shun-Shun;Lin, Chen;Zheng, Xin-Qiang;Devajit, Borthakur;Liang, Yue-Rong
    • Food Science and Biotechnology
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    • v.18 no.3
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    • pp.682-688
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    • 2009
  • Changes in lipophillic pigments concentration and its relation to color of fresh green tea liquor during heat treatment were studied. The results showed liquor greenness decreased markedly with extension of incubation time at $55^{\circ}C$, while the brightness and yellowness changed a little. Significant increase in 'a' and 'b' values of tea liquor was observed at $95^{\circ}C$. Color change of liquor at $55^{\circ}C$ was accompanied by a decrease in the level of chlorophylls, lutein and neoxanthin, and an increase in the pheophytins and ${\beta}-carotene$ levels. However, all pigments except ${\beta}-carotene$ decreased with time extension at $95^{\circ}C$. Significant correlation was found between pigments and color difference index. The browning of fresh green tea liquor was attributed to vicissitudes of lipophillic pigments during heat treatment, especially to the change of chlorophylls/pheophytins ratio. Result also showed addition of $Zn^{2+}$ at 1.6 ${\mu}mol/L$ could partially alleviate the decrease in greenness during heat treatment.

Construct ion of Keyword Index and Improved Search Methods for e-Catalogs Eased on Semantic Relationship (의미적 연결 관계에 기반한 전자 카탈로그에서의 확장된 어휘 인덱스 구축 및 이를 이용한 검색 성능 향상 기법)

  • Lee Dongjoo;Lee Taehee;Lee Sang-goo
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07b
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    • pp.67-69
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    • 2005
  • 본 논문에서는 기 구축된 전자 카탈로그를 의미적 연결 관계에 기초한 확장된 전자 카탈로그로 변환하는 방법을 제안한다. 이를 통해 구축된 확장된 전자 카탈로그에서 의미적 태깅에 의한 확장된 어휘 인덱스 구축 방안과, 이를 이용한 검색 성능 향상 기법을 제안한다. 기존의 전자 카탈로그는 상품 정보가 분류별로 생성된 테이블에 저장되고 저장된 테이블로부터 생성된 키워드 인덱스로부터 검색이 이루어 졌다. 이러한 검색은 상품이 가지는 정보를 데이터베이스에 구축된 테이블에만 한정하게 되어 전자 카탈로그에 포함된 상품이나 분류간의 의미적 연결 관계들을 충분히 이용하지 못하였다 전자 카탈로그에 내재된 의미적 요소를 충분히 활용하기 위해서는 전자 카탈로그를 의미적 연결 관계에 기초한 모델로 구성할 필요가 있다. 본 논문에서는 의미적 모델 기반 전자 카탈로그 시스템으로의 전환 과정을 XML형태의 명세를 이용해 반자동적으로 전환할 수 있는 툴을 구현하며, 단순 키워드 어휘 인덱스 구축이 아닌, 어휘 인덱스의 의미적 확장을 제안하고, 이를 위한 태그 요소로써 어휘에 대한 형태소 분석 결과, 수치 환산 및 확장 요소, 속성간의 도메인 정보 등을 제시하였다. 이를 기반으로 최적의 검색 결과를 얻어 내도록 하는 인접도 평가 함수에 적용하는 방법을 제시한다.

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Semiempirical Calculations of Substituent Effects on the Reactions of Cephem-Like β-Lactam Molecules

  • 이정철;고헌영;창문호;이윤섭
    • Bulletin of the Korean Chemical Society
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    • v.17 no.7
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    • pp.604-607
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    • 1996
  • Semiempirical PM3 MO calculations are applied to estimate both 1-atom (X=S,O,C) and 3-substituent (Y=R, CH2R, SR, CH2SR) effects on the reactions of some 1-atom-replaced and 3-substituted cephem-like β-lactam compounds of thiacephems, oxacephems, and carbacephems. Stabilization energy (SE) of the reaction intermediate for the reaction with a hydroxyl ion can be used to evaluate the facility of a reaction and selected as a chemical reactivity index. With the 1-atom effect only, the SE values obtained imply that thiacephems are generally more reactive than the other two cephem-like molecules and the reactivity order is thiacephems>oxacephems>carbacephems. When it comes to the 3-substituent (Y=R, CH2R, SR, CH2SR) effect, chemical reactivity can be best realized by using a 3-substituted thiacephem molecule capable of giving a resonance-stabilized and electron-rich leaving group after the reaction with a nucleophile. SE values, however, decrease in most cases when an additional intervening ethylene group is present (Y=CH2R, CH2SR). The overall 3-substituent reactivity tendency is SR>CH2SR>R>CH2R.

Efficient excitation and amplification of the surface plasmons

  • Iqbal, Tahir
    • Current Applied Physics
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    • v.18 no.11
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    • pp.1381-1387
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    • 2018
  • One dimensional (1D) grating has been fabricated (using focused ion beam) on 50 nm gold (Au) film deposited on higher refractive index Gallium phosphate (GaP) substrate. The sub-wavelength periodic metal nano structuring enable to couple photon to couple with the surface plasmons (SPs) excited by them. These grating devices provide the efficient control on the SPs which propagate on the interface of noble metal and dielectric whose frequency is dependent on the bulk electron plasma frequency of the metal. For a fixed periodicity (${\Lambda}=700 nm$) and slit width (w = 100 nm) in the grating device, the efficiency of SPP excitation is about 40% compared to the transmission in the near-field. Efficient coupling of SPs with photon in dielectric provide field localisation on sub-wavelength scale which is needed in Heat Assisted Magnetic recording (HAMR) systems. The GaP is also used to emulate Vertical Cavity Surface emitting laser (VCSEL) in order to provide cheaper alternative of light source being used in HAMR technology. In order to understand the underlying physics, far-and near-field results has been compared with the modelling results which are obtained using COMSOL RF module. Apart from this, grating devices of smaller periodicity (${\Lambda}=280nm$) and slit width (w = 22 nm) has been fabricated on GaP substrate which is photoluminescence material to observe amplified spontaneous emission of the SPs at wavelength of 805 nm when the grating device was excited with 532 nm laser light. This observation is unique and can have direct application in light emitting diodes (LEDs).

The Effect of SCB(Slurry Compost ion and Biofilter) Liquid Fertilizer on Growth of Creeping Bentgrasss (저농도 SCB액비의 시용이 크리핑벤트그래스의 생육에 미치는 영향)

  • Ham, Suon-Kyu;Kim, Young-Sun;Kim, Tack-Soo;Kim, Ki-Sun;Park, Chi-Ho
    • Asian Journal of Turfgrass Science
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    • v.23 no.1
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    • pp.91-100
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    • 2009
  • In regional nutrient quota system, livestock manure was applied as liquid fertilizer after slurry composting and biofiltration (SCB) process. This study was conducted to evaluate the effect of SCB liquid fertilizer on turfgrass growth in golf course during 6 month period from May to October in 2008. Fertilizer treatment was designed as follows; non-fertilizer (NF), control (CF; compound fertilizer), S-1 (1L SCB${\cdot}m^{-2}$) and S-2 (2L SCB${\cdot}m^{-2}$). Every treatment was arranged in a randomized complete block design with three replications. In creeping bentgrass, turf color index, chlorophyll content, and dry weight were measured. Results were as follows; A seasonal change pattern of turf grass quality in all treatment increased in April $\sim$ June and September $\sim$ October, whereas it decreased in July $\sim$ August. As compared with NF, turf color index of CF, S-1 and S-2 increased by 1.8%, 1.8%, and 3.3%, respectively and chlorophyll content by 13%, 14%, and 20%, respectively. Dry weight of CF, S-1, and S-2 was higher than that of NFl by 7.7%, 18.2%, and 18.1%, respectively. For turf color index, chlorophyll content, and dry weigh, S-2 showed the best effect, followed by S-1 and CF in creeping bentgrass. These results indicated that the SCB application improves turf growth and quality.

Discrepancies between Calculated and Delivered Dose Distributions of Respiratory Gated IMRT Fields according to the Target Motion Ranges for Lung and Liver Cancer Patients (호흡연동방사선치료시 폐암과 간암환자의 병소 움직임 크기에 따른 선량분포 차이 분석)

  • Kim, Youngkuk;Lim, Sangwook;Choi, Ji Hoon;Ma, Sun Young;Jeung, Tae Sig;Ro, Tae Ik
    • Progress in Medical Physics
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    • v.25 no.4
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    • pp.242-247
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    • 2014
  • To see the discrepancies between the calculated and the delivered dose distribution of IMRT fields for respiratory-induced moving target according to the motion ranges. Four IMRT plans in which there are five fields, for lung and liver patients were selected. The gantry angles were set to $0^{\circ}$ for every field and recalculated using TPS (Eclipse Ver 8.1, Varian Medical Systems, Inc., USA). The ion-chamber array detector (MatriXX, IBA Dosimetry, Germany) was placed on the respiratory simulating platform and made it to move with ranges of 1, 2, and 3 cm, respectively. The IMRT fields were delivered to the detector with 30~70% gating windows. The comparison was performed by gamma index with tolerance of 3 mm and 3%. The average pass rate was 98.63% when there's no motion. When 1.0, 2.0, 3.0 cm motion ranges were simulated, the average pass rate were 98.59%, 97.82%, and 95.84%, respectively. Therefore, ITV margin should be increased or gating windows should be decreased for targets with large motion ranges.

Optical and Structural Analysis of BaSi2O2N2:Eu Green Phosphor for High-Color-Rendering Lighting (고연색 백색 광원용 BaSi2O2N2:Eu 형광체의 광학·구조 특성 분석)

  • Lee, Sunghoon;Kang, Taewook;Kang, Hyeonwoo;Jeong, Yongseok;Kim, Jongsu;Heo, Hoon
    • Korean Journal of Materials Research
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    • v.29 no.7
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    • pp.437-442
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    • 2019
  • Green $BaSi_2O_2N_2:0.02Eu^{2+}$ phosphor is synthesized through a two-step solid state reaction method. The first firing is for crystallization, and the second firing is for reduction of $Eu^{3+}$ into $Eu^{2+}$ and growth of crystal grains. By thermal analysis, the three-time endothermic reaction is confirmed: pyrolysis reaction of $BaCO_3$ at $900^{\circ}C$ and phase transitions at $1,300^{\circ}C$ and $1,400^{\circ}C$. By structural analysis, it is confirmed that single phase [$BaSi_2O_2N_2$] is obtained with Cmcm space group of orthorhombic structure. After the first firing the morphology is rod-like type and, after the second firing, the morphology becomes round. Our phosphor shows a green emission with a peak position of 495 nm and a peak width of 32 nm due to the $4f^65d^1{\rightarrow}4f^7$ transition of $Eu^{2+}$ ion. An LED package (chip size $5.6{\times}3.0mm$) is fabricated with a mixture of our green $BaSi_2O_2N_2$, and yellow $Y_3Al_5O_{12}$ and red $Sr_2Si_5N_8$ phosphors. The color rendering index (90) is higher than that of the mixture without our green phosphor (82), which indicates that this is an excellent green candidate for white LEDs with a deluxe color rendering index.

Effects of Monascus-Fermented Korean Red Ginseng Powder on the Contents of Serum Lipid and Tissue Lipid Peroxidation in Alcohol Feeding Rats (알코올 급여 흰쥐의 혈청 지질 및 조직 과산화지질 농도에 미치는 홍국발효홍삼분말의 영향)

  • Cha, Jae-Young;Ahn, Hee-Young;Eom, Kyung-Eun;Park, Bo-Kyung;Jun, Bang-Sil;Park, Jin-Chul;Lee, Chi-Hyeong;Cho, Young-Su
    • Journal of Life Science
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    • v.19 no.7
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    • pp.983-993
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    • 2009
  • The effects of Monascus-fermented Korean red ginseng (MFRG) on the contents of serum lipids and tissues lipid peroxidation was investigated in alcohol feeding rats (AC group). Serum contents of total lipid and free fatty acid in alcohol feeding rats were significantly increased, but these increases tended to decrease in the AMFRG group. Serum triglyceride content was also significantly decreased in the AMFRG group compared to other groups. Serum content of total-cholesterol was significantly increased in AC group compared to normal control (NC) group, whereas there was no significant difference between the AC and AMFRG groups. Content of HDL-cholesterol in serum was slightly increased in the AC group compared to the NC group, but this increase in the AC group was more significantly increased in the AMFRG group. At the same time, atherogenic index (AI) was also significantly decreased in the AMFRG group compared to the AC group. Contents of thiobarbituric acid reactive substances (TBARS) in the liver, heart, spleen and testes were significantly increased in the AC group compared to the NC group, but these increases were significantly less in the AMFRG group. Contents of liver nonheme ion was increased in the AC group and was significantly decreased in the AMFRG group, which suggested that lipid peroxidation contents are inversely correlated with liver nonheme ion content. Hepatic glutathione concentration was significantly decreased in the AC group, but this content was significantly increased in the AMFRG group and it showed the antioxidant abilities of glutathione. These results suggested that Monascus-fermented Korea red ginseng has anti-atherogenic index (AI) effects as well as antioxidative activities through reduced tissue oxidative stress in alcohol feeding rats.

A Method to Calculate a Pass Rate of the ${\gamma}$-index Analysis in Tomotherapy Delivery Quality Assurance (DQA) (단층치료기를 이용한 방사선 치료의 환자별 정도관리 평가를 위한 감마인덱스의 정량화 방법)

  • Park, Dahl;Kim, Yong-Ho;Kim, Won-Taek;Kim, Dong-Won;Kim, Dong-Hyun;Jeon, Ho-Sang;Nam, Ji-Ho;Lim, Sang-Wook
    • Progress in Medical Physics
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    • v.21 no.4
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    • pp.340-347
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    • 2010
  • DQA, a patient specific quality assurance in tomotherapy, is usually performed using an ion chamber and a film. The result of DQA is analysed with the treatment planning system called Tomo Planning Station (TomoPS). The two-dimensional dose distribution of film measurement is compared with the dose distribution calculated by TomoPS using the ${\gamma}$-index analysis. In ${\gamma}$-index analysis, the criteria such as 3%/3 mm is used and we verify that whether the rate of number of points which pass the criteria (pass rate) is within tolerance. TomoPS does not provide any quantitative information regarding the pass rate. In this work, a method to get the pass rate of the ${\gamma}$-index analysis was suggested and a software PassRT which calculates the pass rate was developed. The results of patient specific QA of the intensity modulated radiation therapy measured with I'mRT MatriXX (IBA Dosimetry, Germany) and DQA of tomotherapy measured with film were used to verify the proposed method. The pass rate was calculated using PassRT and compared with the pass rate calculated by OmniPro I'mRT (IBA Dosimetry, Germany). The average difference between the two pass rates was 0.00% for the MatriXX measurement. The standard deviation and the maximum difference were 0.02% and 0.02%, respectively. For the film measurement, average difference, standard deviation and maximum difference were 0.00%, 0.02% and 0.02%, respectively. For regions of interest smaller than $24.3{\times}16.6cm^2$ the proposed method can be used to calculate the pass rate of the gamma index analysis to one decimal place and will be helpful for the more accurate DQA in tomotherapy.

Fertilization Effects on Soil Properties, Understory Vegetation Structure and Growth of Pinus densiflora Seedlings Planted after Forest Fires (산불피해지에 식재 조림된 소나무임분의 시비처리에 따른 소나무 묘목의 생장, 토양특성 및 하층식생 구조의 변화)

  • Won, Hyung-kyu;Lee, Yoon Young;Jeong, Jin-Hyun;Koo, Kyo-Sang;Lee, Choong-Hwa;Lee, Seung-Woo;Jeong, Yong-Ho;Kim, Choonsig;Kim, Hyungho
    • Journal of Korean Society of Forest Science
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    • v.95 no.3
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    • pp.334-341
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    • 2006
  • This study was to investigate the growth of planted red pine (Pinus densiflora S. et. Z.) seedling, soil properties and understory vegetation structure after fertilizer treatments [unfertilized plot (control), CF plot (Combination Fertilizer), UF plot (Urea Formaldehyde Fertilizer)] in a Pinus densiflora stand planted after the forest fires in Gosung, Gangwon province. The height growth rates of seedlings in four years were 264% in unfertilized, 404% in CF, and 388% in UF plots, respectively. The root collar diameters were increased 340% in unfertilized, 454% in CF, and 427% in UF plots, respectively. No significant changes occurred in soil total nitrogen and potassium ion ($K^+$) with the fertilization. However, available $P_2O_5$, content in the soil surface (0-15 cm) increased with the fertilizer application. Soil organic matter increased significantly with fertilizer treatments, while gradual decrease occurred in unfertilized plots. Sodium ion ($Na^-$) decreased in all sites. Soil pH, CEC, calcium ion ($Ca^{2+}$) and magnesium ion ($Mg^{2+}$) contents were not significantly different among treatments. Although Shannon's species diversity index and species richness in understory vegetation did not change with fertilizer treatments, vegetation cover rates in forest floor increased significantly with the fertilization. These results suggest that the increase of pine seedling growth and vegetation cover rates with fertilization could enhance soil stabilization in forest tire areas.