• 식물분류학회지
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• 제52권2호
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• pp.114-117
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• 2022

Lindera angustifolia is mainly distributed in the temperate climate zone of China but shows an extraordinary distribution, disjunctively isolated on the western coastal islands of Korea. We therefore present the complete chloroplast genome of Korean L. angustifolia. The complete plastome was 152,836 bp in length, with an overall GC content of 39.2%. A large single copy (93,726 bp) and a small single copy (18,946 bp) of the genome were separated by a pair of inverted repeats (20,082 bp). The genome consists of 125 genes, including 81 protein-coding, eight ribosomal RNA, and 36 transfer RNA genes. While five RNA editing genes (psbL, rpl2, ndhB×2, and ndhD) were identified in L. angustifolia from China, the "ndhD" gene was not recognized as an RNA editing site in the corresponding Korean individual. A phylogenetic analysis revealed that Korean L. angustifolia is most closely related to the Chinese L. angustifolia with strong bootstrap support, forming a sister group of L. glauca.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.306-309
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• 2002

A superconducting CICC (Cable-In-Conduit-Conductor) is adopted the KSTAR (Korea Superconducting Tokamak Advanced Research) superconducting magnet system which consists of 16 TF coils and 14 PF coils. For the test of KSTAR CICC, an ambient magnetic field of $\pm$ 8 T With a maximum change rate of 20 T/s is required and a background-field magnet system is being developed for SSTF (Samsung Superconductor Test Facility). The CICC for PF1~5 is used as the conductor for background-field coils to check the validity of the PF CICC design. Two pieces of cables have been fabricated and the cable has the length of 870 m and the diameter of 20.3 mm. A continuous CICC jacketing system is developed for the KSTAR CICC fabrication and the jacketing system uses the tube-mill process, which consists of forming, welding, sizing and squaring procedures. The design specification of CICCs and the fabrication process is described.

• Advances in nano research
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• 제14권2호
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• pp.127-139
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• 2023

This paper studies the free vibration behavior of bi-dimensional functionally graded (BFG) nanobeams subjected to arbitrary boundary conditions. According to Eringen's nonlocal theory and Hamilton's principle, the underlying equations of motion have been obtained for BFG nanobeams. Moreover, the variable substitution method is utilized to establish the structure's state-space differential equations, followed by forming the dynamic stiffness matrix based on state-space differential equations. In order to compute the natural frequencies, the current study utilizes the Wittrick-Williams algorithm as a solution technique. Moreover, the nonlinear vibration frequencies calculated by employing the proposed method are compared to the frequencies obtained in previous studies to evaluate the proposed method's performance. Some illustrative numerical examples are also given in order to study the impacts of the nonlocal parameters, material property gradient indices, nanobeam length, and boundary conditions on the BFG nanobeam's frequency. It is found that reducing the nonlocal parameter will usually result in increased vibration frequencies.

• 환경생물
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• 제40권4호
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• pp.497-509
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• 2022

A strain of Amphidinium species was established from samples collected from the intertidal zone of a sandy beach of Jeju Island, Korea. Its cells were 13.0-15.0 ㎛ in length and 10.0-13.0 ㎛ in width. Its cell shape was round or oval and dorsoventrally flat. A pyrenoid was located in the center of the cell and a nucleus was posteriorly located. Its epicone was small and left-deflecting. Its cingulum had V-shape on the ventral side, forming a ventral ridge and extending to the sulcus. Polygonal amphiesmal vesicles and ring-shaped body scales not described previous were observed on the surface of the cell. Its morphological features were consistent with those of previously described Amphidinium fijiense. Phylogeny based on ITS region and LSU rDNA sequences revealed that this Amphidinium isolate was clearly clustered with other A. fijiense strains, but separated from other Amphidinium species. These results indicate that this Amphidinium isolate is A. fijiense. This study reports its presence for the first time in the intertidal zone of a sandy beach of Jeju Island, Korea.

• Steel and Composite Structures
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• 제44권6호
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• pp.803-816
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• 2022

Composite materials are effective in forming externally bonded reinforcements which find applications related to existing structures repair, attributed to their high strength-to-weight ratio and ease of installation. Among various composites, fibre reinforced polymers (FRP) have somewhat been largely accepted as a commonly utilized composite for such purposes. It is only recently that steel fibres have been considered as additional members of the FRP fibre family, intuitively termed as steel reinforced polymer (SRP). Owing to its low cost and permissibility of fibre bending at sharp corners, SRP is rapidly becoming a viable contender to other FRP systems. This paper investigates the bond behaviour of SRP-concrete joints with different bonded lengths (50, 75, 100, 150 and 300 mm) and widths (15, 30, 40, 50, and 75 mm) using single-lap shear tests. The experimental specimens contain SRP strips with a fixed density of steel fibres (0.472 cords/mm) bonded to the face of concrete prisms. The load responses were obtained and compared in terms of corresponding load and slip boundaries of the constant region and the peak loads. The failure modes of SRP composites are discussed, and the range of effective bonded length is evaluated herein. In the end, a new analytical model was proposed to estimate the SRP-concrete bond strength using a genetic algorithm, which outperforms 22 existing FRP-concrete bond strength models.

• The Plant Pathology Journal
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• 제40권2호
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• pp.205-217
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• 2024

Brown rot disease, caused by Monilinia spp., poses a significant threat to pome and stone fruit crops globally, resulting in substantial economic losses during pre- and post-harvest stages. Monilinia fructigena, M. laxa, and M. fructicola are identified as the key agents responsible for brown rot disease. In this study, we employed the amplified fragment length polymorphism (AFLP) method to assess the genetic diversity of 86 strains of Monilinia spp. isolated from major stone fruit cultivation regions in South Korea. Specifically, strains were collected from Chungcheong, Gangwon, Gyeonggi, Gyeongsang, and Jeolla provinces (-do). A comparative analysis of strain characteristics, such as isolation locations, host plants, and responses to chemical fungicides, was conducted. AFLP phylogenetic classification using 20 primer pairs revealed the presence of three distinct groups, with strains from Jeolla province consistently forming a separate group at a high frequency. Furthermore, M. fructicola was divided into three groups by the AFLP pattern. Principal coordinate analysis and PERMANOVA were applied to compare strain information, such as origin, host, and fungicide sensitivity, revealing significant partition patterns for AFLP according to geographic origin and host plants. This study represents the utilization of AFLP methodology to investigate the genetic variability among M. fructicola isolates, highlighting the importance of continuous monitoring and management of variations in the brown rot pathogen.

• Journal of Applied Biological Chemistry
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• 제59권3호
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• pp.221-225
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• 2016

Tolaasin은 Pseudomonas tolaasii에 의해 생성되어 pore를 형성하는 펩티드 독소이며, 인공재배 버섯의 막 구조를 파괴하여 갈반병을 일으킨다. Tolaasin이 막에서 pore를 형성하는 기작이나 특성은 자세히 알려지지 않았으나, 인공 지질이중막에서 tolaasin에 의한 pore 형성은 제시되었다. Tolaasin에 의한 지질막에서의 pore 형성은 드물게 나타났고, 형성된 pore는 불안정하기에 tolaasin pore의 길이와 지질막의 두께가 서로 일치하지 않을 수 있음이 제안되었다. 그러므로, 탄소수가 다른 지방산으로 이루어진 인지질들을 첨가하여 tolaasin에 의한 용혈활성 변화를 측정하였다. 두 개의 decanoic acids (C10:0, 1,2-didecanoyl-sn-glycero-3-phosphoethanolamine; DDPE)와 myristic acids (C14:0, 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine), stearic acids(C18:0, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine)로 이루어진 phosphatidylethanolamine들을 적혈구와 tolaasin 펩티드가 포함된 반응용액에 가했을 때, DDPE만이 tolaasin에 의한 용혈활성을 촉진하였으며, 나머지 두 인지질은 효과를 보이지 않았다. DDPE를 다양한 농도로 처리하였을 때, tolaasin에 의한 용혈활성은 농도의존적으로 증가하였다. 중간길이의 지방산으로 구성된 인지질은 tolaasin pore 구조와 막지질 사이에 결합하여 pore 주변의 막을 얇게 함으로써 tolaasin pore를 안정화시킬 것으로 여겨진다. 본 연구의 결과는 중간 크기의 지방산으로 구성된 인지질이 tolaasin pore를 막 구조에서 안정화시킴으로써 활성을 증가시키며, 이것은 적혈구 막에서 tolaasin pore의 길이가 막의 두께보다 조금 짧을 것이라는 사실을 제안한다.

• 한국약용작물학회지
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• 제2권2호
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• pp.154-161
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• 1994

폐모(Fritillaria thunbergii)의 자구인편, 줄기, 및 마디조직 및 정단을 구명하고자 실험한 결과는 다음과 같다. 1. 자구형성수는 자구인편조직에 비해 마디나 줄기조직에서, BA처리구보다 kinetin처리구에서 현저히 증가하였다. 줄기조직은 생장이 3cm이하일 때 채취하여 kinetin이 $1.0{\sim}3.0mg\;/L$첨가된 배지에 배양하였을 , 마디조직은 3cm이상 생장한 조직을 kinet이 5.0mg /L 첨가된 배지에 배양하였을 때 자구형성수가 증가하였다. 기내에서 생장한 마디의 액아에서 자구가 직접 형성되는 현상도 관찰되었는데 최고 15개의 자구가 마디에서 형성되었다. 2. 신초가 l0cm 이상 생장한 후 줄기조직을 채취하여 배양하였을 때는 어린 줄기조직보다 자구 형성능력이 감소하였으며 생장조절제의 첨가가 자구형성에 필수적이었고 적정농도는 kinetin 1.0 mg /L였다. 3. 지하에서 생장중인 패모에서는 줄기조직이나 정단이나 자구조직에 비해 구형성율이 높았으며 자구 형성에 적합한 당의 농도는 $5{\sim}7%$였다. 4. 이상의 결과를 종합해 보면 패모의 기내 배양재료로는 자구 인편조직에 비해 3cm정도 생장한 줄기나 마디조직을 이용하는 것이 대량중식에 효과적일 것으로 생각되었다. 특히 줄기나 마디조직은 구형성수가 최고 20배 이상 달하여 중식율이 상당히 높았다. 생장조절제 요구도는 배양재료에 따라 다소 차이가 있으나 Kinetin $1.0{\sim}5.0mg\;/L$가 적합하였다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2003년도 춘계 학술발표대회
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• pp.131-132
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• 2003

Leaf discs and apical meristems were cultured in Murashige and Skoog (MS) medium supplemented with cytokinin and auxin at different concentrations. Callus production was observed in all tested media after six days of incubation. Callus produced in the presence of high concentration of NAA (2.0mg/1) was fragile in texture and yellow in colour. Highest callus formation was observed from leaf discs in the medium supplemented with 1.0mg/1 NAA and 0.5 mg/l BAP in dark at $25{\pm}1{\circ}C$. Percentage of callus formation was 95% and mean callus fresh weight was 654.88 43.53 mg. Shoots were induced from the callus after 4 weeks in 1/2MS medium supplemented with BAP and kinetin both at 0.5mg/1. When elongated shoots were separated and transferred into multiplication medium (MS+0.5mg/1 BAP+0.5mg/1 kinetin) multiplication rate was 6.4 after 6 weeks. Higher concentrations of BAP caused callus production at the base. Direct shoot induction was observed from apical meristems in MS medium in the presence of 0.175 mg/1 IAA + 2.25mg/1 BAP and 0.175 mg/1 IAA + 3.0 mg/1 BAP in 16 hour day at $25{\pm}1{\circ}C$. Explants (apical meristems) elongated to form a single shoot forming a callus at the base. Adventitious buds were sprouted out from the base. Percentage explants which producing shoots was 28.57 and 65.5 respectively. Multiple shoot induction was also observed in the same media. Highest multiple shoot production was observed in the presence of 0.175 mg/l IAA and 3.0mg/l BAP, Mean number of shoots per explant was 5.36 and the mean shoot length was $16.66{\pm}4.15$mm. Shoots (20 30m length) were tested for root induction. Excised shoots were transferred into rooting media, which contains different concentrations of NAA and IAA. Best rooting performance was observed in 1/2MS medium supplemented with 0.1mg/1 NAA after 10 days of incubation in 16 hr photoperiod at $25{\pm}1{\circ}C$. Mean number of roots per shoot was 6 and the mean root length was 252mm. Rooted plantlets were transferred into sterile coir dust:sand (1:4) mixture and maintained in a humid chamber for two weeks, They were gradually exposed to the natural environment. After three weeks they were transferred to pots containing coir dust:sand (1:2) mixture for further development where the 90% survival was observed.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 춘계학술대회 및 임시총회
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• pp.53-53
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• 2015

Agrobacterium tumefaciens-mediated transformation(ATMT) of Flammulina velutipes was used to produce a diverse number of transformants to discover the functions of gene that is vital for its variation color, spore pattern and cellulolytic activity. Futhermore, the transformant pool will be used as a good genetic resource for studying gene functions. Agrobacterium-mediated transformation was conducted in order to generate intentional mutants of F. velutipes strain KACC42777. Then Agrobacterium tumefaciens AGL-1 harboring pBGgHg was transformed into F. velutipes. This method is use to determine the functional gene of F. velutipes. Inverse PCR was used to insert T-DNA into the tagged chromosomal DNA segments and conducting sequence analysis of the F. velutipes. But this experiment had trouble in diverse morphological mutants because of dikaryotic nature of mushroom. It needed to make monokaryotic fruiting varients which introduced genes of compatible mating types. In this study, next generation sequencing data was generated from 28 strains of Flammulina velutipes with different phenotypes using Illumina Hiseq platform. Filtered short reads were initially aligned to the reference genome (KACC42780) to construct a SNP matrix. And then we built a phylogenetic tree based on the validated SNPs. The inferred tree represented that white- and brown- fruitbody forming strains were generally separated although three brown strains, 4103, 4028, and 4195, were grouped with white ones. This topological relationship was consistently reappeared even when we used randomly selected SNPs. Group I containing 4062, 4148, and 4195 strains and group II containing 4188, 4190, and 4194 strains formed early-divergent lineages with robust nodal supports, suggesting that they are independent groups from the members in main clades. To elucidate the distinction between white-fruitbody forming strains isolated from Korea and Japan, phylogenetic analysis was performed using their SNP data with group I members as outgroup. However, no significant genetic variation was noticed in this study. A total of 28 strains of Flammulina velutipes were analyzed to identify the genomic regions responsible for producing white-fruiting body. NGS data was yielded by using Illumina Hiseq platform. Short reads were filtered by quality score and read length were mapped on the reference genome (KACC42780). Between the white- and brown fruitbody forming strains. There is a high possibility that SNPs can be detected among the white strains as homozygous because white phenotype is recessive in F. velutipes. Thus, we constructed SNP matrix within 8 white strains. SNPs discovered between mono3 and mono19, the parental monokaryotic strains of 4210 strain (white), were excluded from the candidate. If the genotypes of SNPs detected between white and brown strains were identical with those in mono3 and mono19 strains, they were included in candidate as a priority. As a result, if more than 5 candidates SNPs were localized in single gene, we regarded as they are possibly related to the white color. In F. velutipes genome, chr01, chr04, chr07,chr11 regions were identified to be associated with white fruitbody forming. White and Brown Fruitbody strains can be used as an identification marker for F. veluipes. We can develop some molecular markers to identify colored strains and discriminate national white varieties against Japanese ones.