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A taxonomy study on 9 taxa of Carex L. (Cyperaceae) in Korea (한국산 사초속(Carex L.) 7절 9종에 대한 분류학적 고찰)

  • Oh, Yong Cha;Lee, Chang Shook;Heo, Sun Young
    • Korean Journal of Plant Taxonomy
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    • v.34 no.3
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    • pp.245-264
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    • 2004
  • For nine taxa of the genus Carex which consist of C. arenicola, C. chordorhiza, C. curta, C. gibba, C. laevissima, C. leiorhyncha, C. neuromrpa, C. maakii and C. remouscula with mixed pistillate and staminate flowers, morphological characters such as inflorescense, spikelet, inflorescence bract, utricle, pistillate and staminate scales, achene, length between two spikelets were observed to find useful characters for their identification. Especially, the shape and the number of spikelet were very useful characters to divide the treated nine taxa into two groups, the their keys were prepared. The first group was comprised of five species of C. arenicola, C. chordorhiza, C. curta, C. gibba, and C. remouscula, which were characterized by broadly oboval or narrowly elliptical shape of spikelet, and 3-9 spikelets per infIorescence and gradual decrease in length between two spikelets. The second group was composed of four species of C. laevissima, C. leiorhyncha, C. neurocarpa, C. maakii, which were distinguished by oval shape of spikelet, and 17-20 spikelets per infIorescence and repetition of increase.

Studies on the Floristic Composition and Periodicity at Joomoonjin Sea Bank (주문진(主文津) 인공(人工) 방파제(防波堤)에 서식(棲息)하는 해조상(海藻相) 및 주기성(週期性)에 관한 연구(硏究))

  • Kim, Yang-Bae
    • Journal of Fisheries and Marine Sciences Education
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    • v.3 no.2
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    • pp.29-46
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    • 1991
  • Benthic marine algal community of a sea bank at Joomoonjin, in the eastern coast of Korea, was investigated monthly in view of floristic composition and seasonal periodicity during from August, 1989 to July 1990. Total number of benthic alga identified were 70 taxa, which composed of 7 species of Chlorophyta, 21 species of Phaeophyta and 42 species of Rhodophyta. The dominant species were Sargassum horneri, Underia pinnatifida, Laminaria japonica and Pachymeniopsis sp.. Vegetation, from the point of phygiognomy, was a mosaic type by these dominant species. The flora was compared with similarity index using S${\phi}$rensen coefficient and grouped by a cluster analysis. As a result, the algal community of this area could be divided into two clusters at similarity level 45% : Flora of water temperature-ascending period(January-July) and flora of water temperature-descending period(August-December). And also, the former flora was subdivided into two clusters at point of the $14^{\circ}C$ sea water temperature : winter flora(January-April) and spring-summer flora(May-July). The flora of this area was characterized as a mixed flora of cold and temperature zone by Cheney's index.

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Influence of Controlled-release Fertilizer Levels on Rice Growth, Weed Control and Nitrogen Efficiency in Paper Mulching Transplanting (벼 종이멀칭이앙 시 완효성비료 수준이 벼 생육, 잡초방제 및 질소효율에 미치는 영향)

  • Jeon, Weon-Tai;Yang, Won-Ha;Roh, Sug-Won;Kim, Min-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.6
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    • pp.345-350
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    • 2006
  • Recently we have interest on rice products developed by environment-friendly management. The technology of paper mulching was practised without herbicide in machine transplanting cultivation of paddy. A field experiment was conducted on Gangseo series (coarse loamy, mixed, nonacid, mesic family of Aquic Fluventic Eutrochrepts) at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Republic of Korea in 2004. This experiment was carried out to evaluate rice growth, weed control and nitrogen efficiency by the different controlled-release fertilizer levels in paper mulching transplanting. Treatments consisted of conventional fertilization, controlled-release fertilizer (100%, 80%, 60%) compared with nitrogen amount ($110kg\;ha^{-1}$) of conventional fertilization and no nitrogen plot. Mulching paper consisted of recycled paper which was coated with biodegradable plastics. There were no differences between conventional rice transplanting and paper mulching on missing hills. Weed occurrence and control were diverse and low as fertilizer amount increased. Plant height and tiller number per hill increased as fertilizer amount decreased. There were no difference between controlled-release fertilizer 80% and conventional fertilization plot on rice growth traits. Leaf color and $NH_4{^+}-N$ in soil had similar trends. There was no difference in yield between controlled-release fertilizer 80% and conventional fertilization plot. Agronomic nitrogen-use efficiency was high as fertilizer amount decreased. Therefore, these results suggested controlled-release fertilizer 80% should be optimum amount under paper mulching transplanting of rice considering weed control, rice growth and nitrogen efficiency.

Properties Evaluation and flowability of Controlled Low Strength Materials Utilizing Industrial By-Products (산업부산물을 활용한 저강도 고유동 채움재의 유동성 및 물성평가)

  • Cho, Yong-Kwang;Kim, Chun-Sik;Nam, Seong-Young;Cho, Sung-Hyun;Lee, Hyoung-Woo;Ahn, Ji-Whan
    • Journal of Energy Engineering
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    • v.27 no.4
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    • pp.64-69
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    • 2018
  • The purpose of this study is to expand the use of coal ash and coal slag in thermal power plants. In addition, controlled low strength materials was developed to prevent mine settlement. Bottom ash and KR slag are mixed at ratio of 7:3 to expand the use of industrial by-products through carbonate reaction and inhibit the exudation of heavy metals. In order to efficiently fill the abandon mine, workability and physical properties were evaluated according to flow. As a result of elution of harmful substance experiment, it was confirmed that the carbonation reaction inhibited the elution of heavy metals. It was confirmed that the difference in water ratio was the difference in specific surface area of the controlled low strength materials. It was confirmed that the working efficiency is excellent when the flowability is 300mm compared to 260mm. compressive strength measurement result was relatively high at 260mm compared to 300mm because the number of pores due to decrease of water ratio was small.

Preparation and characteristics of yogurt added with enzymatically saccharified Korean rice wine lees powder (효소로 당화시킨 주박 분해물을 첨가한 요구르트의 발효 특성)

  • Kim, Dong Chung;Won, Sun Im;In, Man-Jin
    • Journal of Applied Biological Chemistry
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    • v.61 no.4
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    • pp.315-320
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    • 2018
  • This study was carried out to determine the effect of enzymatically saccharified Korean rice wine lees powder (eKRWLP) on the quality characteristics and storage stability of curd yogurt. Yogurt with different contents [0.5-2.0% (w/w)] of eKRWLP was incubated with commercially available mixed lactic acid bacteria (Lactobacillus acidophilus, Streptococcus thermophilus, Bifidobacterium longum) at $40^{\circ}C$ for 18 h. The production of acid measured at pH and titratable acidity of yogurts increased with increasing eKRWLP content. After 12 h fermentation, titratable acidity of eKRWLP yogurt was 0.77-0.90% and was higher than that (0.72%) of yogurt made without eKRWLP. The viable cell counts of lactic acid bacteria in eKRWLP yogurts were increased in proportion to the addition of eKRWLP, and increased up to 8.01-8.13 log CFU/g after 12 h incubation. The repressive effect of whey separation in eKRWLP yogurt curd significantly decreased than that in Korean rice wine lees powder (KRWLP) yogurt. With sensory evaluation, yogurt with 0.5% eKRWLP obtained the highest scores among all eKRWLP yogurts. When eKRWLP yogurts and the control preparations fermented for 12 h were incubated at $4^{\circ}C$, their pHs and titratable acidities were slightly changed and the number of viable lactic acid bacteria were well maintained above $10^7CFU/g$ for 16 days.

Reaction Characteristics of Phytoplankton Before and After the Yellow Dust Event in Taean Peninsula and Yellow Dust Impact Assessment (태안반도주변에서 춘계 황사 전·후 식물플랑크톤 반응특성과 황사분진 영향평가)

  • Yoo, Man Ho;Youn, Seok Hyun;Oh, Hyun Ju;Choi, Joong Ki
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.7
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    • pp.898-906
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    • 2018
  • To investigate the effect of yellow dust on phytoplankton, a field survey and physiological experiments were carried out in the waters near Taean Peninsula from April 22 to 26, 2006, when yellow dust occurred. Phytoplankton populations during the yellow dust period were in the range of $26{\sim}290{\times}10^3cells{\cdot}L^{-1}$, a somewhat low standing crop. An increase in diatoms (a main taxonomic group), especially benthic diatoms such as Paralia sulcate, a typical species for active mixed sea water areas, was also remarkable. In addition, the Chl-a concentration after yellow dust exceeded the Chl-a concentration change range according to the tide before yellow dust. As the concentration of yellow sand increased in a yellow sand treatment experiment, primary productivity decreased, and the maximum assimilation number showed the same tendency. In the 48h culture experiment, primary productivity of the test group was lower than that of the control group at the early stage (T0) of yellow sand treatment, but after 48 hours (T48), the test group showed higher primary productivity than the control group. In particular, the primary productivity of the test group significantly increased to 321 % after 48 hours. Therefore, strong physical environment accompanied by yellow dust may temporarily inhibit the growth of phytoplankton in the waters adjacent to China in the early stage of yellow dust, but the formation of stable water mass has also been identified as a potential factor promoting the growth of phytoplankton.

Culture condition for gametophyte and sporophyte masspropagation of bamboo fern (Coniogramme japonica) using tissue culture (조직배양을 이용한 가지고비고사리의 전엽체와 포자체 대량번식을 위한 배양조건)

  • Park, Kyungtae;Jang, Bo Kook;Lee, Cheol Hee
    • Journal of Plant Biotechnology
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    • v.46 no.2
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    • pp.119-126
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    • 2019
  • This study was conducted to investigate the optimal culture method for gametophyte and sporophyte propagation in Coniogramme japonica (Thunb.) Diels, which can be used in various fields. The propagation of prothallus were cultured in 1/4 - 1 Murashige and Skoog medium and Knop medium for 10 weeks. The results indicated that the fresh weight of prothallus was the highest (14.5 g) in 1MS medium. Subsequently, various concentrations of sucrose, activated charcoal and nitrogen source were also added to 1MS medium and cultured for 8 weeks. The results provided that the sucrose concentration was 3% and the fresh weight of prothallus was the highest 10.8 g. According to the concentration in the range of 8.8 ~ 10.8 g, in the case of activated charcoal, the four treatments showed no significant difference. The nitrogen source was added at a concentration of 30, 60 and 120 mM with the ratio of ${NH_4}^+:{NO_3}^-$ being 1 : 2. As a result, the fresh weight of all treatments increased to similar level but there was no significant difference. We investigated sporophyte formation according to soil type and the highest number of sporophytes at 228.0 was formed in soils mixed with horticultural substrate and decomposed granite at 2 : 1 (v : v). On the other hand, sporophyte was not formed in soils containing peatmoss except for the one with peatmoss and decomposed granite at 2 : 1 (v : v).

Fine mapping of rice bacterial leaf blight resistance loci on K1 and K2 of Korean races of Xoo (Xanthomonas oryzae) using GWAS analysis

  • Hyeon, Do-Yun;Lee, Jeong-Ro;Jo, Gyu-Taek;Raveendar, Sebastin;Sin, Myeong-Jae;Lee, Gyeong-Jun
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.62-62
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    • 2019
  • Bacterial leaf blight(BLB), caused by X. oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice due to its high epidemic potential. Understanding BLB resistance at a genetic level is important to further improve the rice breeding that provides one of the best approaches to control BLB disease. In the present investigation, a collection of 192 accessions was used in the genome-wide association study (GWAS) for BLB resistance loci against four Korean races of Xoo that were represented by the prevailing BLB isolates under Xoo differential system. A total of 192 accessions of rice germplasm were selected on the basis of the bioassay using four isolated races of Xoo such as K1 and K2. The selected accessions was used to prepare 384-plex genotyping by sequencing (GBS) libraries and Illumina HiSeq 2000 pairedend read was used for GBS sequencing. GWAS was conducted using TASSEL 5.0. The TASSEL program uses a mixed linear model (MLM). The results of the bioassay using a selected set of 192 accessions showed that a large number of accessions (93.75%) were resistant to K1 race and K2 resistant germplasm proportion remained between 66.67. The genotypic data produced SNP matrix for a total of 293,379 SNPs. After imputation the missing data was removed, which exhibited 34,724 SNPs for association analysis. GWAS results showed strong signals of association at a threshold of [-log10(P-value)] more than 5 (K1 and K2) for nine of the 39 SNPs, which are plausible candidate loci of resistance genes. These SNP loci were positioned on rice chromosome 2, 9, and 11 for K1 and K2 races. The significant loci detected have also been illustrated and make the CPAS markers for NBS-LRR type disease resistance protein, SNARE domain containing protein, Histone deacetylase 19, NADP-dependent oxidoreductase, and other expressed and unknown proteins. Our results provide a better understanding of the distribution of genetic variation of BLB resistance to Korean pathogen races and breeding of resistant rice.

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Effects of Fructus Amomi Amari, Eucommiae Cortex, Bombyx Batryticatus Extract on Improving Symptoms of Late-onset Hypogonadism (익지인(益智仁), 두충(杜沖), 백강잠(白殭蠶) 혼합추출물이 남성갱년기 증상 개선에 미치는 영향)

  • Park, Sun Young;Ahn, Sang Hyun;Kim, Ho Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.33 no.2
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    • pp.89-101
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    • 2019
  • In recent times, the number of men with late-onset hypogonadism has increased, and interest on this topic has also increased. This study was conducted to investigate effects of the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus on improve late-onset hypogonadism. The experimental subjects consisted of three groups: a control group consisting of 8-week-old male ICR mice that had undergone no treatment, an aging-elicited group (AE group) consisting of 50-week-old ICR male mice that had undergone no treatment, and a Mixed herbal extract treatment group (MT group) consisting of 50-week-old ICR male mice that had undergone the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus treatment (0.1 g/kg/day) for 6 months. After the experiment, the mice from all the experimental groups were dissected, and they were analyzed through histochemical and immunohistochemical methods. The mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus reduces aging-induced cell damage and oxidative stress and increases the secretion of serotonin and B-endorphin in aged mice, and promotes spermatogenesis in seminiferous tubules and reduces apoptosis and oxidative stress, and increases androgen receptor, $17{\beta}-HSD$ and GnRH, increases the ratio of smooth muscle to collagen fibers in the corpus cavernosum, increases eNOS, decreases PDE-5 and oxidative stress in aged mice, so it improves depression, reproductive, sexual problems caused by Late-onset hypogonadism. the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus inhibits the induction of osteoporosis by increasing decreased bone matrix distribution due to aging, increasing the activities of OPC and OPN, which are produced in osteoblasts, and decreasing RANKL, MMP-3 activity, increasing OPG activity. It also reduces muscle damage, oxidative stress, inflammation and apoptosis of muscle tissue, and increases Myo-D in the sartorius muscle of aged mice for improving muscle atrophy caused by by Late-onset hypogonadism.

Effect of Bundling Strategy on Tourists' Evaluation of Tour Packages (여행 패키지의 묶음판매 전략에 관한 연구)

  • Kim, Seung Lee;Lee, Dong Hee
    • International Area Studies Review
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    • v.16 no.1
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    • pp.53-74
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    • 2012
  • The bundling of multiple products/services at a set price has become a popular marketing strategy. However, little is known on how effects of bundling strategy influence tourists' evaluation of tour packages. Tourists evaluate a tour package based on the trade-off between the perceived benefits and costs involved in purchasing the tour package. In other words, the perceived value of the tour package influenced whether tourists to purchase a tour package or not. This study tested a tour package based on the theory of bundling, taking a moderating approach with perceived value. The data for this study wascollected by subjects who live Seoul Metropolitan Area and Gyeonggi Province and 4234 respondents, potential tourists to northeastern U.S.A/Canada. Results show that bundling taken by travel agencies include how many product items to put in a tour package and what degree of discount for the tour package. Also explaining functional relationship among product items in the tour package. Result show that tourists expect a discount, large or small, from purchasing a tour package. And the larger the number of products in a tour packages, the larger the discount size, and low functional relationship among items tourists expect to get.