• Korean Journal of Medicinal Crop Science
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• v.13 no.6
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• pp.278-286
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• 2005

This study was conducted to classify 80 Artemisia spp. collections based on morphological characters and RAPD analysis to get the basic information of Artemisia spp. collections as medicinal plants. The eighty Artemisia spp. collections were classified into 5 groups with the maximum distance 0.82 between clusters based on the complete linkage cluster analysis with morphological traits. Out of 80 operon primer, 10 primers showing polymorphic bands were selected for RAPD analysis. Among the 98 bands amplified with the primers, 68 (69%) bands showed polymorphism. The number of amplified bands ranged from 8 to 10 with an average number of 9.8 bands. Artemisia spp. collections classified into 6 groups with the similarity value of 0.63 in dendrogram derived from the cluster analysis based on RAPDs. Group consisted of 29 collections. Group, which is the largest one, contained 40 collections. Most of the A. asiatica and A. feddei LEV et VNT. were classified into Group and. The rest of the collections (31%) were classified into Group $III{\sim}V$.

• Journal of Korean Society of Forest Science
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• v.98 no.1
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• pp.1-7
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• 2009

We investigated the genetic variation and structure in Korean Arborvitae (Thuja koraiensis Nak.), by 29 examining I-SSR polymorphic loci in 84 individuals distributed among four natural populations in Korea. The level of population genetic diversity ($A_e$=1.44, P=72.42, $H_e$=0.258, S.I.=0.385) was similar to or slightly higher than that of plants with similar ecological traits and life history (Cupressaceae). Most genetic diversity was allocated among individuals within populations (${\Phi}_{ST}$=0.13). The UPGMA dendrogram based on genetic distance failed in showing decisive geographic relationship. The Mt. Bangtae population had the lowest level of genetic diversity and was the most distinctive from the other populations. Mt. Jang population which is possessed of the highest level of genetic variation and Mt. Bangtae population which is consisted of heterogeneous was considered to be a prime candidate for the conservation studies.

• The Korean Journal of Mycology
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• v.38 no.1
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• pp.34-39
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• 2010

We have attempted to verify 30 strains of Hypsizigus marmoreus from various mushroom stocks in Korea using random amplified polymorphic DNA (RAPD) methodology. Chromosomal DNAs of them were extracted and subjected to PCR analyses with 3 random primers. Each PCR produced approximately 30 distinct PCR bands with the size from 200 bp to 3000 bp. A dendrogram was acquired using the unweighted pair-group method with arithmetic average (UPGMA) clustering methodology on the basis of the DNA band pattern. The analysis revealed that 30 strains of H. marmoreus were clustered into two distinct clusters. Cluster 1 contained 3 subgroups while the cluster 2 consisted of rather diverse strains. Interestingly, Hm3-10, a wild strain collected from Deog-Yu mountain, was not included in either clusters, indicative of uniqueness of this strain. We nextly attempted to develop strain-specific DNA markers to verify a specific strain. A unique band in the RAPD gel lane of Hm0-4 was extracted and its sequence was determined. PCR with a primer set from the determined sequence revealed that the primer set gave a 250 bp DNA band only for Hm0-4, indicating that this approach works well for the strain-specific identification of H. marmoreus.

• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.365-372
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• 1998

In this study, we evaluated the genetic relationships of fourty seven Pestalotiopsis theae isolates collected from diseased sweet persimon in various places in southern part of Korea using RAPD (Randomly Amplified Polymorphic DNAs) method. As a result of the amplification, eight primers showed total of 86 bands ranging from 0.3 Kb to 3.2 Kb. Among those 86 bands, 84 polymorphic bands were used for bionominal matrix code (0, 1), and UPGMA dendrogram analysis. Similarities among the compared isolates ranged from below 60% to more than 95%. Most of the compared isolates showed $50{\sim}80%$ similarities. The number of isolate pairs which showed more than 80% similarity were 248. The number of isolate pairs which showed $50{\sim}80%$ similarity were 789, and the number of isolate pairs which showed below 50% similarity were 21. Isolate SP-21 (No.9) showed below 50% similarity with all the isolates compared. At 50% similarity level, all the isolates compared, except isolate SP-21 (No.9), were included in one big group. At 65% similarity level, all the isolates compared, except isolate SP-21 (No.9), were divided into three different groups. At 75% similarity level, all the isolates compared, except isolates SP-47 (No. 23) and SP-21 (No.9), were divided into six different groups.

• Allergy, Asthma & Immunology Research
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• v.10 no.6
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• pp.614-627
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• 2018

Purpose: Asthma is a heterogeneous disease that responds to medications to varying degrees. Cluster analyses have identified several phenotypes and variables related to fixed airway obstruction; however, few longitudinal studies of lung function have been performed on adult asthmatics. We investigated clinical, demographic, and inflammatory factors related to persistent airflow limitation based on lung function trajectories over 1 year. Methods: Serial post-bronchodilator forced expiratory volume (FEV) 1% values were obtained from 1,679 asthmatics who were followed up every 3 months for 1 year. First, a hierarchical cluster analysis was performed using Ward's method to generate a dendrogram for the optimum number of clusters using the complete post-FEV1 sets from 448 subjects. Then, a trajectory cluster analysis of serial post-FEV1 sets was performed using the k-means clustering for the longitudinal data trajectory method. Next, trajectory clustering for the serial post-FEV1 sets of a total of 1,679 asthmatics was performed after imputation of missing post-FEV1 values using regression methods. Results: Trajectories 1 and 2 were associated with normal lung function during the study period, and trajectory 3 was associated with a reversal to normal of the moderately decreased baseline FEV1 within 3 months. Trajectories 4 and 5 were associated with severe asthma with a marked reduction in baseline FEV1. However, the FEV1 associated with trajectory 4 was increased at 3 months, whereas the FEV1 associated with trajectory 5 was persistently disturbed over 1 year. Compared with trajectory 4, trajectory 5 was associated with older asthmatics with less atopy, a lower immunoglobulin E (IgE) level, sputum neutrophilia and higher dosages of oral steroids. In contrast, trajectory 4 was associated with higher sputum and blood eosinophil counts and more frequent exacerbations. Conclusions: Trajectory clustering analysis of FEV1 identified 5 distinct types, representing well-preserved to severely decreased FEV1. Persistent airflow obstruction may be related to non-atopy, a low IgE level, and older age accompanied by neutrophilic inflammation and low baseline FEV1 levels.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.369-376
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• 2009

Cowpea might have been introduced from China to Korea and cultivated for several hundred years but it has never been a staple food crop in Korea. In this study, genetic diversity of 492 Korean cowpea landrace accessions that have passport information was estimated using six SSR markers. The mean of Weir's gene diversity was 0.665 from all accessions investigated in the study. Cowpea gene diversity of six local provinces in Korea was ranged from 0.370 in accessions of Gangwon to 0.680 in Jeonra provinces. Low gene diversity of the cowpea genepool of Gangwon province was probably derived from relatively few introductions. Especially SSR markers VM36 and VM39 seem to be good markers to distinguish the Gangwon accessions from others by occurring at a specific locus with higher than 78% of allele frequency. Except for the Gangwon province with the low genetic diversity, gene diversity of cowpea accessions from other provinces was ranged from 0.600 to 0.680 indicating no big differences among provinces. Distribution pattern of the allele frequencies was similar among the other provinces. This may reveal that Korean farmers might exchange cowpea seeds easily with even their neighbors with geographical barriers. A core collection, 100 landraces, ca. 20% of base collection, was developed at the 70% of a similarity coefficient level using random sampling approaches after stratification of the entire landrace collection based on the phenetic dendrogram. The variability of SSR in the base and core collections of Korean cowpea landrace was compared by calculating Weir's gene diversity. The mean of Weir's gene diversity of the core was 0.707 while that of the base collection was 0.665. The higher diversity index in the core collection indicates that it maintains the initial variability and well represents the base collection. The core collection included one of determinate accession (IT 216155) and two of no branching type accessions (IT 103959 and IT 161024). The core collection could be used to guide more efficient management and utilization of the entire collection. This core collection should be revised periodically as additional accessions are collected and further characterization is conducted.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.28-35
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• 2008

Eleven accessions of Hedera helix, three accessions of Hedera rhombea, one accession of Fatshedera lizei, and one accession of Fatsia japonica were collected and their genetic diversity was measured by using 10 RAPD primers. Approximately ninety seven percentage of polymorphism was detected, because broad germplasm, three genus, was used. Total 97 bands were scored and a dendrogram was constructed by using an UPGMA method. Accessions belonging to Hedera helix tightly clustered in one group: eight accessions showed extremely narrow genetic differences and the other three accessions also showed significant similarity. Despite of their genetic similarity, they showed morphological variations. The morphological variation with a narrow genetic differences indicated that the ivy cultivars have been indeed developed from a mutation breeding program. Genetically most unrelated Fatsia japonica showed a genetic distance of 0.63 on the average between other species. An accession from Fatshedera lizei developed by crossing between two genus, Hedera helix and Fatsia japonica, was allocated together with accessions from Hedera rhombea.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.227-238
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• 2004

Rhododendron micranthum is an endangered species in Korea. In order to develop the strategy of gene diversity conservation, estimation of the amount of genetic diversity, the genetic variation and relationship in the native populations of Rh. micranthum was performed on the basis of AFLP and RAPD analysis. Analysis of 56 accessions derived from 6 populations of Rh. micranthum with four AFLP primer combinations and ten RAPD primers detected a total of 33 polymorphic AFLP fragments and 15 polymorphic RAPD fragments, respectively. By UPGMA cluster analysis with molecular markers, the 56 accessions were grouped into three major clusters at 73.3% genetic similarity; group I consists of most accessions of populations I, II, IV, V and Ⅵ, group II consists of 7 accessions of population III, and group III consists of only two accessions of population IV. The geographic locations of the most accessions derived from six populations were not related to their position in the UPGMA cluster analysis, except for several accessions of populations III and IV. The genetic similarity of among six populations measured by AFLP and RAPD markers ranged from 0.66 to 0.99. Among them, population Ⅵ showed the highest GS with means of 0.87, while population I showed the lowest GS with means of 0.78. This result will be useful for designing the strategy of conservation in the native populations of Rh. micranthum.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.3
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• pp.217-232
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• 2019

It was turned out by shrimp beam trawl monthly survey from March, 2015 to February, 2016 that different species composition and abundance of the fish assemblages in Sacheon Bay and coastal waters off Namhae, Korea were compared. As a result of monthly measured sea temperature and salinity of Sacheon Bay and coastal waters off Namhae, sea temperature of both areas was changed seasonally; however, differences in sea temperature occurred during certain periods depending on the region. Salinity was generally low in Sacheon Bay affected by fresh water, and both areas was low in summer and high in winter. A total of 73 species representing 37 families were collected in Sacheon Bay. The dominant fish species in terms of numbers and biomass were Liparis tanakae, $23,077inds./km^2$, $332.1kg/km^2$. A total of 91 fish species representing 49 families were collected in coastal waters off Namhae. The dominant fish species in terms of numbers were Leiognathus nuchalis, $139,683inds./km^2$ and biomass were Chelidonichthys spinosus, $1,078.6kg/km^2$. Analysis of dendrogram of the clustering showed that Sacheon Bay and coastal waters off Namhae were distinctive featured (global R = 0.691, p = 0.017). And except of summer season (July-October), there was a distinctive feature seasonally (global R = 0.844, p = 0.001). The fish species that appeared in common in both areas, where fish species caught in Sacheon Bay, an important inner bay,were smaller than those caught in coastal waters off Namhae appeared. It presented that Sacheon Bay plays a more important role in spawning and nursery ground for fisheries resource than coastal waters off Namhae, Korea.

• Korea Trade Review
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• v.41 no.3
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• pp.27-42
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• 2016

This study is to investigate seaport clustering by using meta-frontier and cross-efficiency models. Data covers the 13 Asian ports during 2009, 2010 and 2013 with 3 inputs(depth, total area, and number of cranes) and 1 output(TEU). Correlations coefficient from cross-efficiency matrix are used for measuring clustering dendrogram. After that, meta-frontier analysis for investigating whether the clustering using cross-efficiency method increases the meta-efficiency. Empirical main results are as follows: First, group efficiencies of Busan, Incheon, and Gwangyang ports are increased. Second, meta and group efficiencies of China ports are greater than those of Korean ports. Third, distortion of technology gap of Gwangyang is lower than that of Busan and Incheon. Fourth, Gwangyang, clustering with Ningbo, Chingtao, Tokyo and Caosung ports in 2009 and with Dubai port in 2013 can increase the efficiency. Fifth, to enhance the efficiency, Busan port should be clustered to group 2 in 2010 and group 1 in 2013, and Incheon port clustered to group 2 in 2010 and 2013. Fifth, it is empirically investigated that Busan, Incheon and Gwangyang ports can increase the efficiency by using Cross-efficiency and Meta-frontier models. Port policy planner should promote the clustering policy for Busan with Hong Kong, Shanghai, and Singapore, Incheon and Gwangyang with Chingtao, Nagoya, Ningbo, Tokyo, and Kaoshung ports.