• Journal of Aquaculture
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• v.22 no.1
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• pp.92-99
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• 2009

Population dynamics and sexual maturity of Neomysis japonica (Ishikawa and Oshima, 1951) were investigated from a shrimp farm in Tae-an, Korea. N. japonica was collected monthly at the shrimp farm belonging to the Marine and Fisheries Research Institute, the Soonchunhyang University from October 2002 to September 2003. The proportion of female was higher than that of male. The mean carapace length of male (2.42 mm) was larger than that of female (2.31 mm). Brood size increased with increasing female body size. The size of N. japonica at 50% sexual maturity was approximately 4.4 mm. N. japonica females grew faster and reached larger size than males. The mortality rate (z) calculated by length-converted catch curves was $3.46\;yr^{-1}$. The annual recruitment pattern of N. japonica had two major peaks. Log-transformed total length was significantly related with log-transformed carapace length.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.767-771
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• 2005

The Camellia japonica vegetation in the Korean Peninsula was investigated by the methology of the Z-M school. The synthesis table of Camellion japonicae were arranged for association classification from 263 quadrats. The vegetation of Camellia japonica forest, classfied as an alliance includes nine new associations : Camellietum japonicae typicum Jin et Kim 2005, Machilo thunbergii-Camellietum japonicae Jin et Kim 2005, Pino thunbergii-Camellietum japonicae Jin et Kim 2005, Castanopo cuspidatae var. sieboldii-Camellietum japonicae Jin et Kim 2005, Lito japonicae-Camellietum japonicae Jin et Kim 2005, Castnnopo cuspidatae var. thunbergii-Camellietum japonicae Jin et Kim 2005, Querco acutae-Camellietum japonicae Jin et Kim 2005, Neolito sericae-Camellietum japonicae Jin et Kim 2005, Cinnamomo japonicae-Camellietum Japonirae Jin et Kim 2005.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.1-5
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• 1990

The comparative karyological analysis of the Korean treefrogs, Hyla japonica and Hyla suweonensis, were performed by C-banding method. Heteromorphic sex chromosomes, female heterogamety, has been identified in the 3rd chromosomes of H. suweonensis H. suweonensis seem to have sex chromosomes which are Zz/ZW type. The Z chromosomes contain large amount of constitutive heterochromatin, but little heterochromatin is located in the W chromosomes. This is in contrast to all previously known amphibian and most other vertebrate's W or Y chromosomes, except Gastrotheca oui'ern and G. walken (Schmid et al., 1988).

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.406-407
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• 2000

한반도에 서식하는 해초(Seagrass) 중 거머리말속(Zostera, Zosteraceae)은 거머말(Zostera marina), 애기거머리말(Z. japonica), 왕거머리말(Z. asiatica), 수거머리(Z. caulescens), 포기거머리말(Z. caespitosa) 5종이 기재되었다 (Miki, 1932). 이 해들은 연안의 사질 또는 사니질에 서식하며 생태계에 중요한 역할을 담당하고 있다. 그러나 연안의 매립과 개발로 인해 이들 해초지의 감소와 연안생태계의 붕괴가 진행되고 있으나 해초에 대한, 특히 Zostera속에 대한 연구는 미진하다.(중략)

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.97-105
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• 2010

This study focuses on investigating morphological characteristics and variations level in native zoysiagrasses from costal regions and islands in South Korea. In addition, this were collected to conserve germplasm for the breeding of zoysiagrass. One hundred fifty-nine of native zoysiagrasses were collected from 16 different cities and districts. There were morphological evaluations, including plant height, leaf width, leaf length, leaf angle, seed length(SL), seed width(SW), SL/SW ratio and number of seed per spike in native zoysiagrasses. Type of Z. japonica, Z. sinica, Z. macrostachya and Z. matrella showed significant variations in plant height, leaf length, leaf angle and number of seed per spike depending on where they were collected from. On the other hand, little variation were found in leaf width, seed length, seed width and SL/SW ratio. We have discovered a variety of variations among the investigated traits in hybrid zoysiagrass. These results can be used as basic information for development of zoysiagrass breeding.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.3
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• pp.210-222
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• 1983

The chemical factors of topsoil, which are associated with the prediction models of urea nitrogen (N kg/ha) need under the concept of multinutrient factor balance in soil to maintain optimum nutrient balance in rice plant grown in flooded condition, were the x/z and the Kas/Kai values. In the prediction model or equation $NRe=(58.5+0.647x/z){\cdot}F$, the F was difined as the productivity factor, which was considered to be dependent on the variety, climate and soil, and found to be better estimated as the function of Kas/Kai rather than x/z from the equation Fb=0.65+1.086kas/kai, where the x, z, Kas and Kai, respectively, were available $SiO_2$ ppm, % organic matter, K activity ratio or exchangeable $K^+/(\sqrt{Ca+Mg}+Na^+)$ in topsoil and the ideal K activity ratio determined by the equation Kai=0.03+0.00083x/z for standard variety Jinheung. The relative K activity ratio or Kas/kai in topsoil, which have to be equal to 1.0 in the prediction of K fertilizer need for standard Japonica Variety Jinheung, found to be 1.63 for the varieties of Indica ${\times}$ Japonica or Milyang No. 23 grown in Korean condition and 0.322 for the Indica varieties of IR 8, 20, 36 and 42 gown in the Philippines condition. The ideal K activity rations for different Varieties such as Indies ${\times}$ Japonica grown in Korea or $Kai_1$ and Indica grown in the Philippines or $Kai_2$ were computed to be estimated from the following equations respectively ; $\\Kai_1=0.0489+0.001353X/Z\\Kai_2=0.01+0.000267X/Z$.

• Journal of Forest and Environmental Science
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• v.40 no.1
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• pp.53-63
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• 2024

Alnus japonica is indigenous to korea and usually grows in wet lowlands and damp regions in the mountains. Oregonin, is known as a representative compound of the diarylheptanoid mainly found in Alnus species and has been reported to have anti-inflammatory and antioxidant effects. In this experiment, we conducted a study on the presence of orogonin in the native Alnus japonica from the Baekdudaegan mountain range in Korea. We collected a total of 30 samples from Chuncheon, Yangyang, and Jeongseon and conducted experiments. In the HPLC analysis, we confirmed that oregonin was detected in all samples. After the quantitative analysis, samples with the highest content from each region were selected and LC-MS/MS experiments were performed. As a result, the same molecular weight as oregonin, 477.2 m/z, was confirmed in all samples.

• The Korean Journal of Ecology
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• v.28 no.2
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• pp.69-77
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• 2005

The forest vegetation of Namhae-gun was investigated using the methodology of the Z.-M. school of phytosociology from March, 1998 to September, 2003. The forest vegetation was classified into 12 communities, 11 subcommunities, 5 afforestations as follows : Quercus mongolica community(typical subcommunity, Rhododendron schlippenbachii subcommunity), Ouercus serrata community(typical subcommunity, Acer pseudo-sieboldianum subcommunity), Ouercus variablis community(typical subcommunity, Platycarya strobilacea subcommunity), Quercus acutissima community, Carpinus laxiflora community, Carpinus coreans community, Styrax japonica community, Zelkova serrata community, Corylopsis coreana community, Pinus densiflora community(typical subcommunity, Rhododendron mucronulatum subcommunity, Carpinus laxiflora subcommunity), Pinus thunbergii community(typical subcommunity, Eurya Japonica subcommunity), Rhododendron yedoense var. poukhanense community, Chamaecyparis obtusa afforestation, Alnus firma afforestation, Pinus rigida afforestation, Robinia pseudo-acacia afforestation, Cryptomeria japonica afforestation. The soil pH of the study area was ranged from 4.2 to 5.4, and soil moisture content was strongly related to organic matter content. The Corylopsis coreana community contained the highest soil moisture content, whereas Pinus densiflora community contained the lowest one. The content of organic matter were $15.8\sim19.1%$ in the Quercus mongolica, Carpinus coreans and Ouercus serrata communities, $3.3\sim5.4%$ in the Quercus acutissima, Corylopsis coreana and Pinus thunbergii communities, and $2.8\sim5.6%$ in the Pinus rigida and Cryptomeria japonica afforestation. There is significant correlation among the contents of cations($K^+$, $Ca^{2+}$ and $Mg^{2+}$).

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.420-425
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• 2010

The antifungal effects and action mechanisms of styraxjaponoside A and B were investigated. Devoid of hemolytic effect, the compounds had significant effect against several human pathogenic fungal strains, with energy-independent manners. To understand the action mechanisms of the compounds, the flow cytometric analysis plotting the forward scatter and the side scatter, $DiBAC_4$(3) staining and DPH fluorescence analysis were conducted. The results indicated that the actions of the compounds were dependent upon the membrane-active mechanisms. The present study suggests that styraxjaponoside A and B exert their antimicrobial effects via membrane-disruptive mechanisms.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.239-245
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• 2018

Comparative drought resistances of 11 perennial warm-season turfgrasses were evaluated in the field after withholding irrigation for 48 days in summer I and 57 days in summer II. There were significant variations among the grasses in their drought resistances. From two years study of field shoot recovery from drought stress, the relative rankings among the 11 warm-season turfgrasses was as follows. 'Arizona Common' and 'Texturf 10' bermudagrasses [Cynodon dactylon (L.) Pers.], 'Tifgreen' hybrid bermudagrass [C. dactylon (L.) Pers. ${\times}$ C. transvaalensis Davy], and 'Georgia Common' centipedegrass [Eremochloa ophiuroides (Munro.) Mack.] possessed good drought resistances, whereas 'Texas Common' St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] and 'Tifway' hybrid bermudagrass [Cyndon dactylon (L.) Pers ${\times}$ C. transvaalensis Davy] possessed poor drought resistances. 'Texas Common' buffalograss [Buchloe dactyloides (Nutt.) Engelm.], 'Pensacola' bahiagrass (Paspalum notatum Flugge.), and 'Adalayd' seashore paspalum (Paspalum vaginatum Swartz), 'Meyer' zoysiagrass (Zoysia japonica Steud.), 'Emerald' zoysiagrass (Z. japonica Steud. ${\times}$ Z. tenuifolia Willd. ex Trin.) were found to rank intermediate. Visual leaf firing showed the highest correlation (r=-0.84) to shoot recovery from drought stress. Visual leaf rolling (r=-0.59) and canopy-air temperature differential (r=-0.64) also showed very significant correlations, whereas leaf water potential (r=0.54) showed relatively lower correlation.