• The Plant Pathology Journal
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• v.40 no.1
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• pp.73-82
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• 2024

Gardenia (Gardenia jasminoides) is a popular and economically vital plant known for its ornamental and medicinal properties. Despite its widespread cultivation, there has been no documentation of plant viruses on gardenia yet. In the present study, gardenia leaves exhibiting symptoms of plant viral diseases were sampled and sequenced by both metatranscriptome and small RNA sequencing. As a consequence, bean common mosaic virus (BCMV) was identified in gardenia for the first time and named BCMV-gardenia. The full genome sequence of BCMV-gardenia is 10,054 nucleotides (nt) in length (excluding the poly (A) at the 3' termini), encoding a large polyprotein of 3,222 amino acids. Sequence analysis showed that the N-termini of the polyprotein encoded by BCMV-gardenia is less conserved when compared to other BCMV isolates, whereas the C-termini is the most conserved. Maximum likelihood phylogenetic analysis showed that BCMVgardenia was clustered closely with other BCMV isolates identified outside the leguminous plants. Our results indicated that the majority of BCMV-gardenia virus-derived small interfering RNAs (vsiRNAs) were 21 nt and 22 nt, with 21 nt being more abundant. The first nucleotide at the 5' termini of vsiRNAs derived from BCMV-gardenia preferred U and A. The ratio of vsiRNAs derived from sense (51.1%) and antisense (48.9%) strands is approaching, and the distribution of vsiRNAs along the viral genome is generally even, with some hot spots forming in local regions. Our findings could provide new insights into the diversity, evolution, and host expansion of BCMV and contribute to the prevention and treatment of this virus.

• Korean Journal of Environment and Ecology
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• v.32 no.3
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• pp.274-288
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• 2018

This study investigated the environmental factors and fish assemblage in 42 wetlands between spring and autumn of 2017 to evaluate the fish distribution and deduce the management strategy for improving biodiversity in created wetlands located at the Nakdong River basin. The investigation identified a total of 30 fish species and found that the most of wetlands were dominated by exotic fishes such as Micropterus salmoides and Lepomis macrochirus. Fish species such as Rhinogobius brunneus, Opsariichthys uncirostris amurensis, Zacco platypus were less abundant in the area with high density of Micropterus salmoides (static area) because they preferred the environment with active water flow. The pattern analysis of fish distribution in each wetland using the self-organizing map (SOM) showed a total of 24 variables (14 fish species and 10 environmental variables). The comparison of variables indicated that the distribution of fish species varied according to water depth and plant cover rate and was less affected by water temperature, pH, and dissolved oxygen. The plant cover rate was strongly associated with high fish density and species diversity. However, wetlands with low plant biomass had diversity and density of fish species. The results showed that the microhabitat structure, created by macrophytes, was an important factor in determining the diversity and abundance of fish communities because the different species compositions of macrophytes supported diverse fish species in these habitats. Based on the results of this study, we conclude that macrophytes are the key components of lentic freshwater ecosystem heterogeneity, and the inclusion of diverse plant species in wetland construction or restoration schemes will result in ecologically healthy food webs.

• Korean Journal of Environmental Biology
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• v.28 no.4
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• pp.223-230
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• 2010

To investigate the variations of physico-chemical factors in four stations (Hanlim, Aewol, Sinchon, Hamdeok) at Jeju coastal area, Water temperature, Salinity, dissolved oxygen (DO), pH, chemical oxygen demand (COD), suspended solid (SS), ammonia-nitrogen ($NH_4-N$), nitrite-nitrogen ($NO_3-N$), nitrate-nitrogen ($NO_2-N$) were analysed. The ranges of water temperature were from 26.23 to $28.6^{\circ}C$, the salinity were from 31.4 to 32.88‰, the pH were from 8.15 to 8.35, the chemical oxygen were from 0.48 to 0.91 mg $L^{-1}$. A total of 52 strains of marine actinomycetes was isolated from Jeju Island coastal area. They were characterized by determining morphological and physio-biochemical properties, the API kit and confirmed by molecular methods including partial sequencing of 16S rRNA. A neighbor-joining tree of partial 16S rRNA sequences divided the 52 isolates in 2 major groups, 22 strains of Gram positive bacteria/Actinobacteria (division)/Actinomycetales (order)/Streptomycineae (suborder)/Streptomycetaceae (family)/Streptomyces (93.1%) and 2 strains of Streptospotangineae (suborder)/Nocardiopsaceae (family)/Nocardiopsis (6.9%).

• Research in Plant Disease
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• v.14 no.3
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• pp.143-152
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• 2008

Mixed-planting of two rice cultivars, HP ('Hopyeongbyeo') and NP ('Nampyeongbyeo'), having a dissimilar susceptibility to rice blast was practiced for chemical-free control of rice blast in the field. The HP/NP combination was selected for applying under mechanized agricultural conditions. Because they have similar genetic characteristics such as seed germination and heading time, culm length, rice quality and size of rice grains except susceptibility to blast. Incidence of panicle blast was reduced 50.4 % compare with supposed blast incidence by HP/NP mixed-planting when the seeds of two cultivars were combined 1 to 1 as weight. Supposed blast incidence was estimated from reduction of rice blast caused by addition of a resistant cultivar NP. Race diversity of Magnaporthe oryzae was examined for correlation with control effect of HP/NP mixed-planting on rice blast. The population of dominant race KJ-101 was diminished and replaced with various co-existing races and eleven new races were appeared in mixed-planting plot. Total number of race isolated from mixed-planting plot was not largely different from mono-culture. However, detection frequency of the new race was increased and variation of the population size of each race was decreased in mixed-planting plots. It was shown that a biased community with a dominant race (KJ-101 or KI-181) was altered to a balanced one of coexisting races. From these results, it was supposed that the balanced diversity among co-existing races within a community might be correlated to control effect by HP/NP mixed-planting on rice blast. Further more, it should be studied that genetic characteristics of the individual race including a virulence on cv. HP and NP was examined for verifying a correlation of mixed-planting effect and race diversity.

• Composites Research
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• v.30 no.5
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• pp.261-266
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• 2017

Polymer composites are materials in which various fillers are uniformly dispersed on the basis of organic resin. They have excellent processability and diversity for industrial products. Recently, as carbon nanomaterials are developed, there is a great deal of effort to use them as reinforcing fillers to fabricate high performance composite materials. In order to transfer the inherent properties of fillers into composite materials as much as possible, the good dispersion and orientation of fillers, and favorable interfacial interaction between fillers and matrix are considered to be very important. In this review article, we intent to derive and explain the relationship between surface chemical structure of fillers and physical properties of composites as a strategy of high strength and toughness of graphenebased polyimide composites.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.1
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• pp.61-74
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• 2002

The purpose of this study is to propose vegetation management devices through analyzing the actual vegetation, flora, plant community structure and soil chemical concentrations in Weolmi urban nature park, Incheon. The actual vegetation of Weolmi Park in various areas is composed of urbanization area(2 types, 25.9%), landscape planting area(4 types, 16.1%), grass and marsh area(5 types, 7.6%) and mountain forest areal(14 types, 50.4%). The flora is composed of 295 taxa with 80 families, 253 species, 35 varieties and 7 formas, and among them there are 16 naturalized plant families, 39 species, 3 varieties. In reflection of size, the number of the species seems high but most of the them are under influence of human disturbance. Nine survey plots of plant community structure are classified into two groups. One is the semi-natural plant community(Prunus sargentii-Acer palmatum, Quercus accutissma-Prunus sargentii, Quercus serrata-Quercus accutissma-Prunus sargentii, Prunus sargentii, and Zelkova serrata-Prunus sargentii) that migrated finn the planting forest to the natural forest and the other is planting forest(Pinus koraienssis-Pinus thunbergii-Abies holophylla-Chamaectparis obtusa, Prunus sargentii, Pinus thunbergii-Alnus firma, Zelkova serrata). The average pH is 4.65 which means the soil acidity is quite high. The concentration of K, Ca, Mg and base saturation is very low. It seems that the environmental pollutants from Incheon Port and industrial plants near by survey site and long-distance transport of air pollutants from China made the soil condition worse. On the basis of the results above, six vegetation management devices are suggested: 1) removing the hazard plants(Pueraia thunbergiana and Humulus japonica), 2) natural landscape management of the middle and long term, 3) increasing species diversity, 4) Robinia pseudoacacia management, 5) keeping the naturalized plants from being distributed any further inside the mountain forest, 6) improving soil acidification.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.6
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• pp.77-83
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• 2001

The purpose of this study is to provide the fundamental material and information for the plant maintenance after rooftop planting through physiochemical characteristics. The characteristics of artificial soils after rooftop planting from 1993 to 1999 was investigated. Fourteen investigation areas were selected from 4 cities(2 areas selected by each year). The analysis of the circumstances of the areas, the physical characteristics, and the chemical characteristics of the soil were conducted. The artificial soil pH ranged 5.26∼7.40 showing that after construction the soil pH tended to decrease. The soil bulk density of the site was lowest in 1999, 0.15g/㎤, and used to increase toward 1993. We found the fact that the soil bulk density increased gradually after rooftop application . The coefficients of permeability of the soils range from 0.016 to 0.052 cm/sec, which seemed to be in good permeability level. The artificial soils had relatively high water moisture capacity of 62.69∼71.36%. The soil organic matter content of the artificial soils ranged from 0.43 to 1.34%. The exchangeable caution concentration in the artificial soil ranged, Na, 2.36∼4.71mg·{TEX}$kg^{-1}${/TEX}, Mg 0.88∼2.84mg·{TEX}$kg^{-1}${/TEX},K 2.97∼9.61 mg·{TEX}$kg^{-1}${/TEX}, and Ca 9.39∼28.23 mg·{TEX}$kg^{-1}${/TEX}. The amount of total N ranged from 0.003 to 0.286% in study sites. Soil chemical properties varied year to year and showed little tend. The research results showed that some characteristics of the artificial soil were changed after rooftop planting, i.e., soil pH and soil bulk density. Soil bulk density had a negative relationship with the coefficient of permeability, showing that the drainage condition might be limited after some period. This study suggests that a diversity of the research in the changes of the plant growth basis on the areas after construction.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1203-1210
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• 2011

Function-driven metagenomic analysis is a powerful approach to screening for novel biocatalysts. In this study, we investigated lipolytic enzymes selected from an alluvial soil metagenomic library, and identified two novel esterases, EstDL26 and EstDL136. EstDL26 and EstDL136 reactivated chloramphenicol from its acetyl derivates by counteracting the chloramphenicol acetyltransferase (CAT) activity in Escherichia coli. These two enzymes showed only 27% identity in amino acid sequence to each other; however both preferentially hydrolyzed short-chain p-nitrophenyl esters (${\leq}C_5$) and showed mesophilic properties. In vitro, EstDL136 catalyzed the deacetylation of 1- and 3-acetyl and 1,3-diacetyl derivates; in contrast, EstDL26 was not capable of the deacetylation at $C_1$, indicating a potential regioselectivity. EstDL26 and EstDL136 were similar to microbial hormone-sensitive lipase (HSL), and since chloramphenicol acetate esterase (CAE) activity was detected from two other soil esterases in the HSL family, this suggests a distribution of CAE among the soil microorganisms. The isolation and characterization of EstDL26 and EstDL136 in this study may be helpful in understanding the diversity of CAE enzymes and their potential role in releasing active chloramphenicol in the producing bacteria.

• Journal of the Korean Chemical Society
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• v.62 no.1
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• pp.36-42
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• 2018

In this study, we investigated the characteristics of analogies generated by middle school students in the perspectives of the number of analogies, the mapping understanding, and the diversity and originality of analogs. We also compared the results by students' scientific creativity, field independence/dependence, and learning approach. Participants in this study were 250 9th graders in Seoul. The analyses of the results revealed that the students of higher scientific creativity generated more analogies, had a higher level of mapping understanding, and used more diverse and original sources. Field independent students had a higher level of mapping understanding. However, the other characteristics of analogies were not related to field independence/dependence. Meaningful understanding approach was related to all the characteristics of analogies, while rote learning approach was not related to any characteristics of analogies. Educational implications of these findings are discussed.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.362-376
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• 2020

Rabbit meat bekasam is a traditional fermentation product from Indonesia. This study aimed to determine the chemical and microbiological characteristics of rabbit meat bekasam during the fermentation process in order to isolate, characterize (in vitro and in vivo), and identify lactic acid bacteria (LAB) as the probiotic candidate. The chemical contents of bekasam on 7-day fermentation were investigated in explorative and experimental methods in a completely randomized design. A proximate analysis reported a decrease in the moisture content, fat and carbohydrate content, and an increase in protein content. Also, lactic acid content was increased from 0.48% to 1.12%, and pH was decreased from 5.3 to 4.3. Other properties indicated different values, such as bacteria (2.75×10⁶ to 4.45×10⁷ CFU/g), total LAB (3.82×10⁶ to 4.67×10⁸ CFU/g), total yeast (9.89×10⁶ to 3.82×10⁸ CFU/g) and total mould (4.34×10¹ to 4.86×10³ CFU/g). The experiment produced nine LAB isolates, including two probiotics subjected to further 16S rRNA gene analysis, which indicated that Lactobacillus buchneri was the potential probiotic isolate. After being tested on BALB/c mice, L. buchneri could improve the immune system by inhibiting the growth of Coliform and Salmonella.