• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.336-336
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• 2011

Over the past decades, organic semiconductors have been investigated intensely for their potential in a wide range of optoelectronic device applications since the organic materials have advantages for very light, flexible and low cost device fabrications. In this study, we fabricated small-molecule organic solar cells (OSCs) based on chloro[subphthalocyaninato]boron(III) (SubPc) as an electron donor and $C_{60}$ as an electron acceptor material. Recently SubPc, a cone-shaped molecule with $14{\pi}$-electrons in its aromatic system, has attracted growing attention in small-molecule OSC applications as an electron-donating material for its greater open-circuit voltage (VOC), extinction coefficient and dielectric constant compared to conventional planar metal phthalocyanines. In spite of the power conversion efficiency (PCE) enhancement of small-molecule OSC using SubPc and $C_{60}$, however, the study on the interface between donor-acceptor heterojunction of this system is limited. In this work, SubPc thin films at various thicknesses were deposited by organic molecular beam deposition (OMBD) and the evolution of surface morphology was observed using atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM). We also investigated the influence of film thickness and surface morphology on the PCE of small-molecule OSC devices.

• Korean Journal of Microbiology
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• v.35 no.2
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• pp.115-120
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• 1999

Multiple Sequence Alignment of DNA and protem sequences is a imnport'mt tool in the study of molecular evolution, gene regulation. and prolein suucture-function relationships. Progressive pairwise alignment method generates multiple sequence alignment fast but not necessarily with optimal costs. Dynamic programming generates multiple sequence alig~~menl with optimal costs in most cases but long execution time. In this paper. we suggest genetlc algorithm lo improve the multiple sequence alignment generated from the cnlent methods, describe the design of the genetic algorithm, and compare the multiple sequence alignments from 0111 method and current methods.

• Molecules and Cells
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• v.22 no.1
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• pp.78-88
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• 2006

The phylogeny of the subfamily Tephritinae (Diptera: Tephritidae) was reconstructed from mitochondrial 16S ribosomal RNA gene sequences using 53 species representing 11 currently recognized tribes of the Tephritinae and 10 outgroup species. The minimum evolution and Bayesian trees suggested the following phylogenetic relationships: (1) monophyly of the Tephritinae was strongly supported; (2) a sister group relationship between the Tephritinae and Plioreocepta was supported by the Bayesian tree; (3) the tribes Tephrellini, Myopitini, and Terelliini (excluding Neaspilota) were supported as monophyletic groups; (4) the non-monophyletic nature of the tribes Dithrycini, Eutretini, Noeetini, Tephritini, Cecidocharini, and Xyphosiini; and (5) recognition of 10 putative tribal groups, most of which were supported strongly by the statistical tests of the interior branches. Our results, therefore, convincingly suggest that an extensive rearrangement of the tribal classification of the Tephritinae is necessary. Since our sampling of taxa heavily relied on the current accepted classification, some lineages identified by the present study were severely under-sampled and other possible major lineages of the Tephritinae were probably not even represented in our dataset. We believe that our results provide baseline information for a more rigorous sampling of additional taxa representing all possible major lineages of the subfamily, which is essential for a comprehensive revision of the tephritine tribal classification.

• Genomics & Informatics
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• v.17 no.3
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• pp.27.1-27.9
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• 2019

Supernumerary B chromosomes were found in Lilium amabile (2n = 2x = 24), an endemic Korean lily that grows in the wild throughout the Korean Peninsula. The extra B chromosomes do not affect the host-plant morphology; therefore, whole transcriptome analysis was performed in 0B and 1B plants to identify differentially expressed genes. A total of 154,810 transcripts were obtained from over 10 Gbp data by de novo assembly. By mapping the raw reads to the de novo transcripts, we identified 7,852 differentially expressed genes (log₂FC > |10|), in which 4,059 and 3,794 were up-and down-regulated, respectively, in 1B plants compared to 0B plants. Functional enrichment analysis revealed that various differentially expressed genes were involved in cellular processes including the cell cycle, chromosome breakage and repair, and microtubule formation; all of which may be related to the occurrence and maintenance of B chromosomes. Our data provide insight into transcriptomic changes and evolution of plant B chromosomes and deliver an informative database for future study of B chromosome transcriptomes in the Korean lily.

• Molecules and Cells
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• v.25 no.3
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• pp.323-331
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• 2008

Plants are continually exposed to a variety of potentially pathogenic microbes, and the interactions between plants and pathogenic invaders determine the outcome, disease or disease resistance. To defend themselves, plants have developed a sophisticated immune system. Unlike animals, however, they do not have specialized immune cells and, thus all plant cells appear to have the innate ability to recognize pathogens and turn on an appropriate defense response. Using genetic, genomic and biochemical methods, tremendous advances have been made in understanding how plants recognize pathogens and mount effective defenses. The primary immune response is induced by microbe-associated molecular patterns (MAMPs). MAMP receptors recognize the presence of probable pathogens and evoke defense. In the co-evolution of plant-microbe interactions, pathogens gained the ability to make and deliver effector proteins to suppress MAMP-induced defense responses. In response to effector proteins, plants acquired R-proteins to directly or indirectly monitor the presence of effector proteins and activate an effective defense response. In this review we will describe and discuss the plant immune responses induced by two types of elicitors, PAMPs and effector proteins.

• Clinical and Experimental Pediatrics
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• v.63 no.6
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• pp.195-202
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• 2020

Developments in next-generation sequencing (NGS) techogies have assisted in clarifying the diagnosis and treatment of developmental delay/intellectual disability (DD/ID) via molecular genetic testing. Advances in DNA sequencing technology have not only allowed the evolution of targeted panels but also, and more currently enabled genome-wide analyses to progress from research era to clinical practice. Broad acceptance of accuracy-guided targeted gene panel, whole-exome sequencing (WES), and whole-genome sequencing (WGS) for DD/ID need prospective analyses of the increasing cost-effectiveness versus conventional genetic testing. Choosing the appropriate sequencing method requires individual planning. Data are required to guide best-practice recommendations for genomic testing, regarding various clinical phenotypes in an etiologic approach. Targeted panel testing may be recommended as a firsttier testing approach for children with DD/ID. Family-based trio testing by WES/WGS can be used as a second test for DD/ID in undiagnosed children who previously tested negative on a targeted panel. The role of NGS in molecular diagnostics, treatment, prediction of prognosis will continue to increase further in the coming years. Given the rapid pace of changes in the past 10 years, all medical providers should be aware of the changes in the transformative genetics field.

• BMB Reports
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• v.52 no.9
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• pp.540-547
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• 2019

Immune repertoire is a collection of enormously diverse adaptive immune cells within an individual. As the repertoire shapes and represents immunological conditions, identification of clones and characterization of diversity are critical for understanding how to protect ourselves against various illness such as infectious diseases and cancers. Over the past several years, fast growing technologies for high throughput sequencing have facilitated rapid advancement of repertoire research, enabling us to observe the diversity of repertoire at an unprecedented level. Here, we focus on B cell receptor (BCR) repertoire and review approaches to B cell isolation and sequencing library construction. These experiments should be carefully designed according to BCR regions to be interrogated, such as heavy chain full length, complementarity determining regions, and isotypes. We also highlight preprocessing steps to remove sequencing and PCR errors with unique molecular index and bioinformatics techniques. Due to the nature of massive sequence variation in BCR, caution is warranted when interpreting repertoire diversity from error-prone sequencing data. Furthermore, we provide a summary of statistical frameworks and bioinformatics tools for clonal evolution and diversity. Finally, we discuss limitations of current BCR-seq technologies and future perspectives on advances in repertoire sequencing.

• Molecules and Cells
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• v.44 no.12
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• pp.861-878
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• 2021

The human genome contains many retroviral elements called human endogenous retroviruses (HERVs), resulting from the integration of retroviruses throughout evolution. HERVs once were considered inactive junk because they are not replication-competent, primarily localized in the heterochromatin, and silenced by methylation. But HERVs are now clearly shown to actively regulate gene expression in various physiological and pathological conditions such as developmental processes, immune regulation, cancers, autoimmune diseases, and neurological disorders. Recent studies report that HERVs are activated in patients suffering from coronavirus disease 2019 (COVID-19), the current pandemic caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection. In this review, we describe internal and external factors that influence HERV activities. We also present evidence showing the gene regulatory activity of HERV LTRs (long terminal repeats) in model organisms such as mice, rats, zebrafish, and invertebrate models of worms and flies. Finally, we discuss several molecular and cellular pathways involving various transcription factors and receptors, through which HERVs affect downstream cellular and physiological events such as epigenetic modifications, calcium influx, protein phosphorylation, and cytokine release. Understanding how HERVs participate in various physiological and pathological processes will help develop a strategy to generate effective therapeutic approaches targeting HERVs.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.56.2-56.2
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• 2021

Constraining the structure and thus the fate of giant molecular clouds (GMCs), the primary sites of star formation in galaxies, is crucial to understand the evolution of galaxies themselves. Exploiting the unprecedented sensitivity and angular resolution of the Atacama Large Millimeter/sub-millimeter Array (ALMA), we have measured the spatially-resolved (~ 20 pc resolution) properties of the GMCs in two nearby late-type galaxies, NGC 5806 (SAB(s)b) and NGC 6753 ((R)SA(r)b), as part of the WISDOM project. Although these results are preliminary, we identified ~ 200 resolved GMCs in NGC 5806 within a radius of 500 pc, most within a nuclear ring structure, and ~ 400 resolved GMCs in NGC 6753 within a radius of 2 kpc, most within a flocculent spiral structure. The GMCs of NGC 5806 have similar sizes but slightly higher linewidths than clouds in the Milky Way disc. Because the GMCs also have higher surface densities, the calculated cloud Virial parameters are nevertheless about unity, suggesting that the GMCs of NGC 5806 are in gravitational equilibrium and thus long lived. This is contrary to other WISDOM results on earlier-type galaxies, where large cloud linewidths are likely due to shear associated with the local (circular) orbital motions (rather than the clouds' self-gravity), and the clouds are either marginally or not gravitationally bound. These results support the notion that spheroids alter the dynamical states of clouds (morphological quenching), that are otherwise (i.e. in galaxy discs) fairly homogenous and similar to those of the Milky Way.

• Animal Systematics, Evolution and Diversity
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• v.39 no.3
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• pp.99-113
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• 2023

The nudibranch is one of the most colorful gastropod species found in oceans worldwide. Unlike many other gastropod groups, the nudibranch loses an external shell in the adult stage, but instead develops various chemical defense systems. More than 2,500 nudibranch species have been reported worldwide, and 73 species are currently recorded in Korean waters. In this study, we present morphological descriptions, DNA barcode information of mtDNA cox1 sequence, and taxonomic review for five nudibranch species: Apata pricei (MacFarland, 1966), Doto rosacea Baba, 1949, Janolus toyamensis Baba and Abe, 1970, Polycera abei (Baba, 1960), and Trinchesia sibogae (Bergh, 1905). Of these, we also provide in-depth discussion of taxonomic issue of A. pricei that was previously subdivided into two subspecies, A. pricei pricei and A. pricei komandorica. Our morphological examination and molecular analyses of the mtDNA cox1 sequences indicate that these two subspecies are not taxonomically warranted. The phylogenetic information for the other nudibranch species from mtDNA cox1 sequence analysis is also included, providing a molecular basis for species identification and inferring their local phylogenies within each of the species groups discussed herein.