• Title/Summary/Keyword: $L_{MAX}$

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Characteristics of Indigenous Rhizobium to Korean Soils -I. Symbiotic Potentials of Bradyrhizobium japonicum Populations and Their Colony Morphological Characteristics in Yeongnam Soils (우리나라 토착근류균(土着根瘤菌)의 제(諸) 특성(特性) 연구(硏究) -I. 영남지역(嶺南地域) 토착(土着) 대두근류균(大豆根瘤菌)의 접종효과(接種效果)와 취락형태적(聚落形態的) 분포특성(分布特性))

  • Kang, Ui-Gum;Somasegaran, Padma;Jung, Yeun-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.23 no.1
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    • pp.60-66
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    • 1990
  • Soybean [Glycin max (L.)] cv. Jangbaekkong was inoculated with 5 cultivated- and 5 uncultivated upland soils, in Yeongnam area, as soil inoculum and NifTAL peat inoculum as standard for soil inoculum potentials by Bradyrhizobium japonicum. 120 Bradyrhizobium japonicum isolates out of the soil populations were scored of three colony morphologies, designed "Dry", "Wet", and "Dry/Wet", and symbiotic effectiveness between "Dry" and "Wet" was compared. The results obtained were summarized as follows: 1. Indigenous populations of B. japonicum were above $10^4cells/g$. soil at the cultivated upland soils but were a few at the uncultivated upland soils except a colluvivum, orchard previously, in Yeongnam area. 2. Inoculum potentials of the cultivated upland soils were higher than the NifTAL inoculum and generally, nodule mass compensated nodule number for symbiotic effectiveness of soil populations. 3. Colony morphologies of soil populations showed the different proportions of "Dry" and "Wet" so that "Dry" types were dominant at the cultivated upland soils while "Wet" types at the uncultivated upland soils. 4. "Dry" colony morphology significantly exhibited higher symbiotic effectiveness than "Wet" types in nodule fresh weight, shoot dry weight, and shoot dry weight/nodule fresh weight. Therefore, as long as soil inoculum potentials, the growth of soybean at the cultivated upland soils could presumedly be affected by soil populations of Bradyrhizobium japonicum of "Dry" colony morphology.

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Synthesis and Color Tuning of Poly(p-phenylenevinylene) Containing Terphenyl Units for Light Emitting Diodes

  • Jin, Young-Eup;Kim, Jin-Woo;Park, Sung-Heum;Kim, Hee-Joo;Lee, Kwang-Hee;Suh, Hong-Suk
    • Bulletin of the Korean Chemical Society
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    • v.26 no.11
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    • pp.1807-1818
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    • 2005
  • New PPV based conjugated polymers, containing terphenyl units, were prepared as the electroluminescent (EL) layer in light-emitting diodes (LEDs). The prepared polymers, poly[2,5-bis(4-(2-etylhexyloxy)phenyl)-1,4-phenylenevinylene] (BEHP-PPV), poly[2-(2-ethylhexyloxy)-5-(4-(4-(2-etylhexyloxy)phenyl)phenyl)-1,4-phenylenevinylene] (EEPP-PPV) and poly[2-(2-ethylhexyloxy)-5-(9,9-bis(2-etylhexyl)fluorenyl)-1,4 phenylenevinylene] (EHF-PPV), were soluble in common organic solvents and used as the EL layer in double layer light-emitting diodes (LEDs) (ITO/PEDOT/polymer/Al). The polymers were prepared by the Gilch reaction. The number-average molecular weight $(M_n)$, weight-average molecular weight $(M_w)$, and the polydispersities (PDI) of these polymers were in the range of 9000-58000, 27000-231000, 2.9-3.9, respectively. These polymers have quite good thermal stability with decomposition starting above 320-350. The polymers show photoluminescence (PL) with maximum peaks at around 526-562 nm (exciting wavelength, 410 nm) and blue EL with maximum peaks at around $\lambda_{max}$ = 526-552 nm. The current-voltageluminance (I-V-L) characteristics of polymers show turn-on voltages of 5 V. Even though both of EEPP-PPV and BEHP-PPV have the same terphenyl group in the repeating unit, EEPP-PPV with directly substituted alkoxy group in the back bone has longer effective conjugation length than BEHP-PPV, and exhibits red shift in the PL spectra. Both of EEPP-PPV and EHF-PPV have ter-phenyl units and directly substituted alkoxy group in back bone. EHF-PPV with fluorenyl unit attached to the PPV backbone has shorter effective conjugation length than EEPP-PPV with biphenyl unit, and exhibits blue shift in the PL spectra.

Preparation of minor ginsenosides C-Mc, C-Y, F2, and C-K from American ginseng PPD-ginsenoside using special ginsenosidase type-I from Aspergillus niger g.848

  • Liu, Chun-Ying;Zhou, Rui-Xin;Sun, Chang-Kai;Jin, Ying-Hua;Yu, Hong-Shan;Zhang, Tian-Yang;Xu, Long-Quan;Jin, Feng-Xie
    • Journal of Ginseng Research
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    • v.39 no.3
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    • pp.221-229
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    • 2015
  • Background: Minor ginsenosides, those having low content in ginseng, have higher pharmacological activities. To obtain minor ginsenosides, the biotransformation of American ginseng protopanaxadiol (PPD)-ginsenoside was studied using special ginsenosidase type-I from Aspergillus niger g.848. Methods: DEAE (diethylaminoethyl)-cellulose and polyacrylamide gel electrophoresis were used in enzyme purification, thin-layer chromatography and high performance liquid chromatography (HPLC) were used in enzyme hydrolysis and kinetics; crude enzyme was used in minor ginsenoside preparation from PPD-ginsenoside; the products were separated with silica-gel-column, and recognized by HPLC and NMR (Nuclear Magnetic Resonance). Results: The enzyme molecular weight was 75 kDa; the enzyme firstly hydrolyzed the C-20 position 20-O-${\beta}$-D-Glc of ginsenoside Rb1, then the C-3 position 3-O-${\beta}$-D-Glc with the pathway $Rb1{\rightarrow}Rd{\rightarrow}F2{\rightarrow}C-K$. However, the enzyme firstly hydrolyzed C-3 position 3-O-${\beta}$-D-Glc of ginsenoside Rb2 and Rc, finally hydrolyzed 20-O-L-Ara with the pathway $Rb2{\rightarrow}C-O{\rightarrow}C-Y{\rightarrow}C-K$, and $Rc{\rightarrow}C-Mc1{\rightarrow}C-Mc{\rightarrow}C-K$. According to enzyme kinetics, $K_m$ and $V_{max}$ of Michaelis-Menten equation, the enzyme reaction velocities on ginsenosides were Rb1 > Rb2 > Rc > Rd. However, the pure enzyme yield was only 3.1%, so crude enzyme was used for minor ginsenoside preparation. When the crude enzyme was reacted in 3% American ginseng PPD-ginsenoside (containing Rb1, Rb2, Rc, and Rd) at $45^{\circ}C$ and pH 5.0 for 18 h, the main products were minor ginsenosides C-Mc, C-Y, F2, and C-K; average molar yields were 43.7% for C-Mc from Rc, 42.4% for C-Y from Rb2, and 69.5% for F2 and C-K from Rb1 and Rd. Conclusion: Four monomer minor ginsenosides were successfully produced (at low-cost) from the PPD-ginsenosides using crude enzyme.

Effect of Chemotaxis on Nodulation in Bradyrhizobium-Soybean Symbiosis (근류균의 화학주성이 근류형성에 미치는 영향)

  • Kang, Sang-Jai;Park, Woo-Churl
    • Korean Journal of Soil Science and Fertilizer
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    • v.27 no.2
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    • pp.136-146
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    • 1994
  • To research the effect of chemotaxis of Rhizobia toward the root exudate on nitrogen fixing ability in soybean Rhizobia symbiosis system. Root exudate from seedlings of Glycine max. L was collected aseptic conditions. B. japonicum KCTC 2422 induced the formation of symbiotic nitrogen fixing nodules on the root of soybean plant and possessed motility and chemotaxis toward the 2mM proline. LPN-100 mutant was $Nod^-$, $Che^+$, and LPN-101 was $Che^-$, $Nod^+$ strains. Physiological properties of mutants were similar to parent strain. The crude root exudate was tested for its chemotactic ability using the capillary tube method. Chemotactic responses of RCR 3407 toward crude root exudate were 2.2, 2.6, 2.9, those of KCTC 2422 were 2.3, 2.9, 3.0, respectively. The crude root exudate was fractionated into neutral, cationic and anionic fractions. Chemotactic responses of KCTC 2422 was least with anionic fraction, most with neutral and intermediate with cationic fraction. B. japonicum KCTC 2422 was attracted by carbohydrates, amino acids and carboxylic acid. Carbohydrates and amino acids were good chemoattractants and carboxylic acids were intermediate chemoattractants. The peak concentration was $10^{-3}M$ for ribose, glucose, glutamine, aspartic acid and carboxylic acids, with exception of xylose, arabinose, tryptophan, which elicited maximum responses at $10^{-4}M$. The formation of nodules and nitrogenase activity of soybean inoculated with KCTC 2422 was determined in 7days after inoculation, and those of LPN-101 was detected in 15days after inoculation, but LPN-100 didn't form of nodules in soybean plants.

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Screening of Inhibitory activities on Angiotensin Converting Enzyme from Medicinal plants (약용식물의 Angiotensin Converting Enzyme 저해활성 탐색)

  • Choi, Geun-Pyo;Chung, Byung-Hee;Lee, Dong-Il;Lee, Hyeon-Yong;Lee, Jin-Ha;Kim, Jong-Dai
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.5
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    • pp.399-402
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    • 2002
  • Angiotensin converting enzyme(ACE) belongs to the class of zinc protease and plays an important role in the regulation of blood pressure. In this experiment, we investigated the inhibitory activities of medicinal plant extracts on ACE. Fifty medicinal plants were selected and the extracts were prepared by refluxing with 70% methanol. Among the extracts, eleven medicinal plant extracts such as Sedum sarmentosum Bunge, Petasites japonicus(s.et z.) Max, Rubus coreanus, Morus bombycis Koidz, Acorus calamus var. angustatus, Glycyrhiza glabra, Equisetum hyemale, Portulaca oleracea L., Prunella vulgaris var. lilacina Nakai, Sorbus commixta Hedl, Allium thunbergii showed more than 50% inhibitory activities, and Paeonia suffruticosa Andr., lnula helenium, Acanthopanax senticosus Harms, Dendrobium moniliforme, Juglans mandshurica, Zizyphus jujuba, Leonurus artemisia, Aster scaber Thunb, Vitex rotundifolia, Platycodon grandiflorum, Prunus persica, Ligularia fischeri showed $40{\sim}49%$ inhibitory activities. Therefore these extracts which contain high ACE inhibitory activities may be useful as antihypertension agents and to the treatment of hypertension.

키토산 분자량 변화에 따른 수중의 여러 중금속들의 제거에 관한 연구

  • 이승원;김동석
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.05a
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    • pp.292-296
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    • 2003
  • Autoclaving처리를 하지 않은 키토산과 autoclaving처리한 키토산과의 중금속 흡착실험을 해 본 결과 다음과 같은 결과를 도출 할 수 있었다. 1) 먼저 중금속간의 흡착능을 고찰하기 위하여 Langmuir와 Freundlich 흉착등온식에 적용시켜 본 결과 Freundlich 흡착등온식 보다는 Langmuir 흡착등온식이 보다 적합한 것으로 나타났다. 2) 시간에 따라서 autoclaving 처리한 키토산의 중금속 제거 가능성과 그 효율을 검토하기 위하여 각 중금속간의 Langmuir 흡착등온식을 이용하여 $q_{max}$를 나타냈다. 15 min > 60 min > 0 min 순으로 모든 중금속 제거 실험에서 15 min 동안 autoclaving 처리한 키토산의 중금속 흡착량이 가장 높은 것으로 나왔다. 그러므로 기존의 키토산 보다는 15 min동안 autoclaving 처리한 키토산이 중금속 제거에 더 좋은 흡착제로써 역할을 할 수 있을 것으로 판단된다. 3) 키토산을 이용한 중금속 제거에서는 $Pb^{2+}$ > $Cd^{2+}$ > $Cu^{2+}$ > $Cr^{3+}$순서로 제거가 되었다. 여러 연구자들의 실험 결과를 종합해 볼 때 Pb$^{2+}$가 중금속 중에 제거가 잘 된다는 연구 결과가 많이 발표 되었으며, $Cd^{2+}$, $Cu^{2+}$, $Cr^{3+}$의 경우에는 흡착제의 종류에 따라서 제거되는 순서가 다르다는 연구 결과들이 보고 되고 있다. 그러나 어떠한 이유로 중금속의 제거에 차이가 있는지에 대해서는 명확한 결론이 내려져 있지 않는 실정이다. 이러한 중금속간의 경쟁적인 관계에 대해 더 많은 세밀한 연구가 이루어져야 할 것 같다.는 0.52mg/$\ell$~0.99mg/$\ell$~의 범위이었다. 신천에 금호강물을 혼합한 이후에도 부유물질, 생화학적산소요구량, 암모니아태 질소, 총인 등의 농도가 개선되지 않았다. 즉 금호강물의 혼합은 신천수질환경사업소에서 배출되는 방류수에 함유되어 있을 2차 오염물질의 희석이라는 이점외의 수질개선효과는 확인되지 않았다.l years and a new type of transfer crane has been developed. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of the process. On the basis of the simplified model, the simulation was performed and the results could be confirmed by the experiments under various conditions.뢰, 결속 등 다차원의 개념에 대한 심도 깊은 연구와 최근 제기되고 있는 이론

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Varietal Responses of Ten Soybean(Glycine max L.) to Sulfur Dioxide Tolerance : A Comparison of Foliar Injuries and Yields in Relation to Physiological Properties of Leaves. (아황산가스에 대한 주요 콩 품종간의 내성 비교)

  • Park, Ki-Sun;Ku, Ja-Hyeong
    • Korean Journal of Environmental Agriculture
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    • v.15 no.4
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    • pp.455-463
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    • 1996
  • Studies were carried out to determine the effect of sulfur dioxide on leaf injury and yield of ten soybean cultivars. Plants were fumigated with 2.0 ppm of $SO_2$ for 4 or 8 h in a closed-top field chamber. In the comparison of foliar injury, Paldalkong and Eunhakong were more susceptible to $SO_2$ than Bogwangkong, Jangsukong, and Jangkeungkong. Correlations between chlorophyll contents, peroxidase activity, and stomatal resistance of leaves and foliar susceptibility were insignificant. However, significant correlations $(r=-0.611^{\ast})$ were found between superoxide dismutase activity and foliar injury rates. Dry weight, number of pods and total grains were significantly reduced by $SO_2$ fumigation but plant height, number of nods and weight of 100 grains were not affected. Yield reduction rates were higher in Eunhakong and Paldalkong than in Bogwangkong and Jangkeungkong. A liniar relationship was found between foliar injury rate and the percent crop loss with a significant coefficient of b=-1.17 in the susceptible cultivar of Paldalkong, but Bogwangkong, insusceptible cultivar, showed lower value of -0.165.

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Effect of Light Quality During Imbibition and Culture on Growth of Soybean Sprout (광질에 따른 콩나물의 생장)

  • 강진호;박아정;전병삼;윤수영;이상우
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.6
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    • pp.427-431
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    • 2002
  • Lateral roots of soybean sprout might reduce the quality. The study was done to measure the effect of light quality treated during 24 hour imbibition or 6 day culture on growth and development of soybean sprouts on the 6th day after culture. With the soybean seeds imbibed in 4 ppm benzyladenopurine (BA) solution for last 6 hours of the imbibition, blue and red lights were treated during the imbibition, but during 6 day culture, blue and red or far-red light treatments were done for 50 minutes or 5 hours a day, respectively, the periods taking for their cotyledons to turn green color, On the 6th day after culture, the soybean sprouts were classified by 4 categories on the base of hypocotyl length;>7cm, 4 to 7cm, <4cm and non-germination, and their lateral roots, hypocotyl diameters and fraction dry weights were measured. Blue and red lights treated during the imbibition completely blocked lateral root formation regardless of the lights treated during the culture, and showed nearly the same rate of hypocotyls of longer than 4cm. The period of each light treatment forced during the culture did not influence the growth of soybean sprouts. far-red light treated for 5 hours everyday, however, had the least rate of seed germination and hypocotyls of longer than 7cm of the light quality treatments. In addition, red and far-red lights almost equally having the commercial soybean sprouts of longer than 4cm hypocotyls move elongated and selenderized than blue light and dark treatment, meaning the growth and morphology of soybean sprouts was affected by light treatments during the culture.

Analysis of Genetic Diversity in Soybean Varieties Using RAPD Markers (사료작물로 이용이 가능한 한국 재배콩의 RAPD 표지인자에 의한 유전적 다양성 분석)

  • Lee, Sung-Kyu;Kim, Bum-Jun
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.18 no.4
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    • pp.277-284
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    • 1998
  • Random amplified polymorphic DNA (RAPD) analysis was used to detect the genetic diversity of soybean (Glycine max (L.) Merr.) varieties and field bean (Glycine soza Sieb. and Zucc.) Five soybean varieties and one field bean were analysed with random primers using the polymerase chain reaction (PCR). Nine primers of a total twenty random primer were selected to amplify DNA segments. A total of 74 PCR products were amplified and 67.6% of which were polymorphic. The size of DNA molecule is ranged 0.13~2.0Kb and typically generated four to eight major bands. Specific genetic marker were revealed in primer sequence 5'-CAG GCC CIT C-3', 5'-TGC TCT GCC C-3' and 5'-GTC CAC ACG G-3', respectively. Genetic similarity between each of the varieties were calculated from the pair-wise comparisons of amplification products and a dendrogram was constructed by an unweighted pair-group method with arithmethical means (UPGMA). The results indicate that intervarietal relationships of soybean have a narrow genetic base and between the varieties, Hwanggum-kong and Seckryang-bootkong is more closely related than the rest of varieties, and field bean is related quite distant.

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Exercise Prescription and Dietary Modification for Prevention and Treatment of Chronic Degenerative Disease II. On Arteriosclerosis and Hypertension (성인병의 예방과 치료를 위한 영양과 운동처방 II. 고혈압과 동맥경화에 미치는 영향)

  • 백영호
    • Journal of Life Science
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    • v.9 no.2
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    • pp.231-240
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    • 1999
  • Regular exercise is effective in preventing coronary disease such as angina pectoris and infarction, inside it can lower the blood pressure and aids in weight control and release of stress. Risk factors of arteriosclerosis is hypertension, hyperlipidemia, diabetes, obesity, physical inactivity and excessive smoking. Arteriosclerosis begins at young age worsens with age, particulary in male. For people with risk factors of arteriosclerosis, it is important to prevent arteriosclerosis-related disease with dietary, living pattern and exercise prescription. Dietary fibers promote exercise of the digestive tract and shortens the time food remains inside the digestive tract. It can prevent obesity, hyperlipidemia, arteriosclerosis and colin cancer by blocking the absorption of cholesterol. Various vegetables and sea foods are lichen unsaturated fats and prevent the absorption of cholesterol inside the digestive tract. Essential fatty acids and unsaturated fats which are contained in vegetable oils, promotes metabolism while preventing absorption. In fruits, pectin water-soluble fiber, is present and lowers the level of cholesterol. By consuming foods that low in cholesterol and saturated fats, and rich in unsaturated fats, aliomentotherapy alone can reduce the plasma cholesterol by 10~l5$\%$. For ideal exercise, it should be aerobic with intensity of 60~80$\%$ HRmax, duration of 15~60min/day. The frequancy of 3~6/week is desirable the better exercise prescription is endurance aerobic exercise. To get more effect exercise, exercise consistency is very important.

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