• Korean Journal of Environment and Ecology
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• v.9 no.2
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• pp.147-155
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• 1996

To investigate the structure and the conservation strategy of natural forest at Dongdaesan, Turobong, Sangwangbong Area in Odaesan National Park, 27 plots(20$\times$20m) set up with random sampling method. Three groups were classified by cluster analyses. High positive correlations was proved between Tilia amurensis and Acer pseudo-sieboldianum, Malus faccata and Syringa reticulata var. mandshurica, Prunus padus and Viburnum sargentii, and High negative correlations was proved between Quercus mongolica and pronus padus, Tilia amurensis and Prunus padus, Acer pseudo-sieboldianum and Prunus padus. Species diversity(H') of investigated area was calculated 0.9586~1.1814.

• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.158-163
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• 1999

Powdery mildew diseases previously unrecorded in Korea were noticed on four species of ornamental trees. Field observations on each disease were described and the causal fungi were identified. Powdery mildew of Symplocos chinensis for. pilosa was found to occur mildly, especially on plants growing in shade. The causal fungus was identified as Microsphaera nomurae U. Braun. Cornus florida was found to be infected with Microsphaera pulchra Cooke & Peck and supposed to be epidemic in nursery. Powdery mildew of Malus baccata occurred on young leaves and herbaceous stems in nursery. The causal fungus was classified as Podosphaera leucotricha (Ellis & Everh.) Salmon. Powdery mildew of Ulmus macrocarpa was found to occur in autumn and severe on young shoots. Uncinula kenjiana Homma was identified as the causal fungus.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.757-763
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• 2012

To acquaint correct information about the fertilizability and analyze S-allele based genetic diversity among Korean apples, we investigated self-incompatibility genotypes by PCR and cross-pollination tests in field. As a consequence, S-genotypes of Korean apples were distributed within narrow genetic diversity as $S_1S_3$ for 'Hongro' and 'Saenara'; $S_1S_9$ for 'Gamhong' and 'Manbok'; $S_3S_5$ for 'Seokwang'; $S_3S_9$ for 'Sunhong', 'Seohong', 'Chukwang', and 'Hwahong'. Coupled with cross-pollination experiments in field, our results provide support for the view that apples are fully compatible when both of their S-loci differ and semi-compatible when they carry one different and one identical S-locus. Furthermore, the results of this study indicate that S-alleles have to be extended to various genotypes for Korean apple breeding.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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• pp.130-137
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• 2007

A disease resistance related gene, MbR7, was identified in the wild apple species, Malus baccata. The MbR7 gene has a single open reading frame (ORF) of 3,288 nucleotides potentially encoding a 1,095-amino acid protein. Its deduced amino acid sequence resembles the N protein of tobacco and the NL27 gene of potato and has several motifs characteristic of a TIR-NBS-LRR R gene subclass. Ectopic expression of MbR7 in Arabidopsis enhanced the resistance against a virulent pathogen, Pseudomonas syringae pv. tomato DC3000. Microarray analysis confirmed the induction of defense-related gene expression in 35S::MbR7 heterologous Arabidopsis plants, indicating that the MbR7 gene likely activates a downstream resistance pathway without interaction with pathogens. Our results suggest that MbR7 can be a potential target gene in developing a new disease-resistant apple variety.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.280-285
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• 2010

In the course of a searching natural antifungal compounds from plant sources, we found that the methanol extract ($3,000\;{\mu}g/ml$) of Malus domestica fruits had potential of control against rice blast (Magnaporthe grisea) and tomato late blight (Phytophthora infestans). Under bioassay-guided purification, we isolated phloretin, a phenolic compound, with in vivo antifungal activity against M. grisea. By 1-day protective application of phloretin ($500\;{\mu}g/ml$), the compound strongly inhibited the disease development of M. grisea and P. infestans on rice and tomato seedlings, respectively. And red pepper anthracnose caused by Colletotrichum coccodes also was moderately suppressed. However, rice sheath blight (Rhizoctonia solani AG1), and barley powdery mildew (Blumeria graminis f. sp. hordei) were hardly controlled. In addition, the compound showed in vitro antifungal activity against some plant pathogenic fungi including Phytophthora capsici, Alternaria panax, Sclerotinia sclerotiorum, R. solani AG4, and M. grisea. This is the first report on the antifungal activity of phloretin against plant pathogenic fungi.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.1
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• pp.34-44
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• 2004

Objectives: The objective of this study was to teach patients clinically useful external application of acne. Methods: We investigated the effects and manufacturing methods of the medical herbs published in the woman's monthly magazines according to "Zhong-Yao-Da-Ci-Dian(中藥大辭典)". Results: We investigated that Saururus chinensis Baill.(三白草), Houttuynia cordata Thunb.(魚腥草), Coix lachrymajobi L.(薏苡仁) were discovered 3 times, Brassica oleracea L.(甘藍), Raphanus sativus L.(래복), Daucus carota L. var. Sativa DC.(홍래복), Oryza sativa L.(米皮糠), Spinacia oleracea L.(파래), Cucumis sativus L.(黃爪) 2 times, and Glycyrrhiza uralensis Fisch.(甘草), Gallus gallus domesticus Braisson.(？子白), Aloe vera L.(노회), Phascolus radiatus L.(綠豆), Prunus persica Batsch.(桃葉), Lycopersicon esculentum Mill.(番茄), Taraxacum mongolicum Hand.-Mazz.(蒲公英), Prunus armeniaca L.(杏仁), Musa paradisiaca L. var. Sapientum O. ktze.(香蕉) and Malus pumila Mill.(평과) were discovered once in woman's monthly magazine during last two years. According to the effects, we classificated four groups which were defervescence(淸熱), subsidence of edema(消腫), pyorrhea(排膿) and gloss(滋潤) group. Conclusion & discussion : We suggested the use of each medical herbs on the Consensus conference on acne classification. We needed the further study on the manufacturing method, the time of use and the dose

• The Plant Pathology Journal
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• v.22 no.2
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• pp.168-173
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• 2006

To develop the diagnostic method for the viral infection in apple, the partial genes corresponding to the N-terminal region of RNA polymerase of Apple stem grooving virus (ASGV) and coat protein of Apple chlorotic leaf spot virus (ACLSV) were characterized from the infected apple cultivars in Korea. Based on the nucleotide sequences of the characterized partial genes, the virus gene-specific primers were designed for the detection of ASGV and ACLSV infected in species of Malus. The RT-PCR using the primers for the genes of ASGV and ACLSV successfully gave rise to 404 and 566 bp DNA fragments, respectively. Using those viral gene-specific primers, the multiplex RT-PCR assays were also established to diagnose the mixed infection by ASGV and ACLSV simultaneously. Furthermore, the control primers, which have to be included for the RT-PCR as an internal control, were designed using the nucleotide sequence of the gene encoding elongation factor $1{\alpha}(EF1{\alpha})$. This multiplex RT-PCR including the control primers provides more reliable, rapid and sensitive assay for the detection of ASGV and ACLSV infected in Korean apple cultivars.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.3
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• pp.245-250
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• 2004

This paper proposes a new method of measuring an air interface distance between a solid immersion lens(SIL) applied magneto-optic technology and the disk surface. For applying near-field recording (NFR) technology to the magneto-optic storage devices for the next generation, it is positively necessary to maintain the small air gap under about 100㎚. We design an apparatus that consists of some optical components such as a prism, a polarizer and an analyzer. By using the Fresnel reflection coefficient equation, Jones matrices calculation and Malus's law, we establish a mathematical model for understanding the characteristics of the system. The simulations are based on the mathematical model and through the simulation results which is made with various cases we can estimate the performance of the new optical gap sensor system. Experimental results, which are also based on the mathematical model for specific cases, are in good agreement with simulated ones and demonstrate the possibility as the new optical gap sensor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.597-605
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• 2000

This study was investigated to compare the volatile flavor components in fuji, tsugaru, hongro and jonathan (Malus pumila M.). In the results of analyzing the volatie components of four varieties apples with GC-FID and GC/MS, 100, 68, 85 and 94 volatiles were identified in fuji, tsugaru, hongro and jonathan apples, respectively. Hexanal, butanol, (E)-2-hexenal, hexanol,3-methy-1-butanol, ethy1actate, ethyl butyrate, 2-methybutyl acetate and hexy1 acetate were major flavor components in the four varieties of apple, though there were several differences in composition of colatiles.

• Journal of Conservation Science
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• v.1 no.1 s.1
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• pp.12-26
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• 1992

Ilsan peat-bed site, newly constructed city area, is located at the northern part of Seoul. This site is situated near the mouth of Han river, which flows through central Korea. Many fossil woods were excavated from this site, and surveyed the wood anatomical features. Totally 90 specimens were identified into 10 species including two roots and five barks which were not identified in detail. Alnus japonica and A. maxmowiczii are the most common and occupied 26. 7%, 34.4% of the total specimen number respectively, and then other species which excavated from Ilsan area are follows : Fraxinus rhynchophylla(18.9%), Lepido-balanus spp.(3.3%), Maackia amurensis(2.2%), Diospyros spp.(2.2%), Juglans mandshrica(1.1%), Prunophora spp.(1.1%), Malus or Pyrus spp.(1.1%), Rhamnus spp.(1.1%). Among the identified species there are fairly some species growing in the central - or northern temperate zone, such as A. maxmowiczii, F. rhynchophylla, Lepidobalanus spp., M. amurnsis, J. mandshurica, Rhumnus spp. Therefore, it can be estimated that the former temperature of Ilsan area was same or slightly cold than today. The species bearing fruit for food as .J, mandshunca, Diospyros spp., Prunophora spp., Mulus or Pyrus spp. were regarded as artificially planting trees, because they do not grow together in the same site.