• Applied Chemistry for Engineering
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• v.33 no.5
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• pp.496-501
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• 2022

In this study, an anode material for lithium secondary batteries was manufactured using petroleum-based residual oil, which is a petroleum refining by-product. Among petroleum-based residual oils, pyrolysis fuel oil (PFO), fluidized catalyst cracking-decant oil (FCC-DO), and vacuum residue (VR) were used as carbon precursors. The physicochemical characteristics of petroleum-based residual oil were confirmed through Matrix-assisted laser desorption/ionization Time-of-Flight (MALDI-TOF) and elemental analysis (EA), and the structural characteristics of anode materials manufactured from residual oil were evaluated using X-ray crystallography (XRD) and Raman spectroscopic techniques. VR was found to contain a wide range of molecular weight distributions and large amounts of impurities compared to PFO and FCC-DO, and PFO and FCC-DO exhibited almost similar physicochemical characteristics. From the XRD analysis results, carbonized PFO and FCC-DO showed similar d₀₀₂ values. However, it was confirmed that FCC-DO had a more developed layered structure than PFO in Lc (Length of a and c axes in the crystal system) and La values. In addition, FCC-DO showed the best cycle characteristics in electrochemical characteristics evaluation. According to the physicochemical and electrochemical results of the petroleum-based residual oil, FCC-DO is a better carbon precursor for a lithium secondary battery than PFO and VR.

• Journal of Plant Biotechnology
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• v.49 no.3
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• pp.178-186
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• 2022

The tetraploid Solanum acaule is a wild potato species from Bolivia widely used for potato breeding because of its diverse attractive traits, including resistance to frost, late blight, potato virus X, potato virus Y, potato leafroll virus, potato spindle tuber viroid, and cyst nematode. However, the introgression of useful traits into cultivated potatoes via crossing has been limited by differences in endosperm balance number between species. Somatic fusion could be used to overcome sexual reproduction barriers and the development of molecular markers is essential to select proper fusion products. The chloroplast genome of S. acaule was sequenced using next-generation sequencing technology and specific markers for S. acaule were developed by comparing the obtained sequence with those of seven other Solanum species. The total length of the chloroplast genome is 155,570 bp, and 158 genes were annotated. Structure and gene content were very similar to other Solanum species and maximum likelihood phylogenetic analysis with 12 other species belonging to the Solanaceae family revealed that S. acaule is very closely related to other Solanum species. Sequence alignment with the chloroplast genome of seven other Solanum species revealed four InDels and 79 SNPs specific to S. acaule. Based on these InDel and SNP regions, one SCAR marker and one CAPS marker were developed to discriminate S. acaule from other Solanum species. These results will aid in exploring evolutionary aspects of Solanum species and accelerating potato breeding using S. acaule.

• Journal of Life Science
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• v.31 no.7
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• pp.671-676
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• 2021

A cDNA encoding the protein lethal (2) essential for life [l(2)efl] was cloned from Gryllus bimaculatus and named GBl(2)efl. This protein is composed of 189 amino acids, including an N-glycosylation site and 15 phosphorylation sites. Its predicted molecular mass is 21.19 kDa, with a theoretical isoelectric point of 6.2. The secondary structure of GBl(2)efl was predicted from the identification of random coils (56.08%), alpha helices (22.22%), extended strands (17.99%), and beta turns (3.7%) through sequence analyses. A homology analysis revealed that GBl(2)efl exhibited a high similarity with other species at the amino acid level, ranging from 52% to 69%. While GBl(2)efl mRNA expression was higher in the dorsal longitudinal flight muscle following a three-day starvation and in the Malpighian tubules following a one-day starvation, no changes in expression were detected in other tissues. Furthermore, tunicamycin-induced endoplasmic reticulum (ER) stress resulted in an approximately 1.8-fold higher expression in the fat body compared with the wild type.

• BMB Reports
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• v.55 no.6
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• pp.275-280
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• 2022

The treatment of atopic dermatitis (AD) is challenging due to its complex etiology. From epidermal disruption to chronic inflammation, various cells and inflammatory pathways contribute to the progression of AD. As with immunosuppressants, general inhibition of inflammatory pathways can be effective, but this approach is not suitable for long-term treatment due to its side effects. This study aimed to identify a plant extract (PE) with anti-inflammatory effects on multiple cell types involved in AD development and provide relevant mechanistic evidence. Degranulation was measured in RBL-2H3 cells to screen 30 PEs native to South Korea. To investigate the anti-inflammatory effects of Parasenecio auriculatus var. matsumurana Nakai extract (PAE) in AD, production of cytokines and nitric oxide, activation status of FcεRI and TLR4 signaling, cell-cell junction, and cell viability were evaluated using qRT-PCR, western blotting, confocal microscopy, Griess system, and an MTT assay in RBL-2H3, HEK293, RAW264.7, and HaCaT cells. For in vivo experiments, a DNCBinduced AD mouse model was constructed, and hematoxylin and eosin, periodic acid-Schiff, toluidine blue, and F4/80-staining were performed. The chemical constituents of PAE were analyzed by HPLC-MS. By measuring the anti-degranulation effects of 30 PEs in RBL-2H3 cells, we found that Paeonia lactiflora Pall., PA, and Rehmannia glutinosa (Gaertn.) Libosch. ex Steud. show an inhibitory activity of more than 50%. Of these, PAE most dramatically and consistently suppressed cytokine expression, including IL-4, IL-9, IL-13, and TNF-α. PAE potently inhibited FcεRI signaling, which mechanistically supports its basophil-stabilizing effects, and PAE downregulated cytokines and NO production in macrophages via perturbation of toll-like receptor signaling. Moreover, PAE suppressed cytokine production in keratinocytes and upregulated the expression of tight junction molecules ZO-1 and occludin. In a DNCB-induced AD mouse model, the topical application of PAE significantly improved atopic index scores, immune cell infiltration, cytokine expression, abnormal activation of signaling molecules in FcεRI and TLR signaling, and damaged skin structure compared with dexamethasone. The anti-inflammatory effect of PAE was mainly due to integerrimine. Our findings suggest that PAE could potently inhibit multi-inflammatory cells involved in AD development, synergistically block the propagation of inflammatory responses, and thus alleviate AD symptoms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.305-318
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• 2022

To minimize the effects of aging-related comorbidities and to maintain a good quality of life and physical independence for a longer period, the improvement of lifestyle and dietary habits is essential, and healthy foods can be helpful. Among them, medicinal plant such as ginseng (Panax ginseng) and bellflower (Platycodon grandiflorum) contain natural functional substances and have been used for disease treatment and prevention since ancient times. This review summarizes the scientific of these treatments basis by investigating the pharmacological and pharmacokinetic effects of major functional substances on the aging-related health effects of Panax ginseng and Platycodon grandiflorum. The main functional substances of Panax ginseng and Platycodon grandiflorum are saponins, which have a similar molecular structure and confirmed anti-inflammatory, antioxidant, neuroprotective, anticancer, and anti-metabolic syndrome effects (improvement of hypertension, dyslipidemia, diabetes, and obesity). Both types of saponins in Panax ginseng (Ginseonside) and Platycodon grandiflorum (Platycoside) have very low absorption profiles in their purified state, but methods to increase absorption in the body through extraction or fermentation have been studied.

• Journal of Life Science
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• v.33 no.1
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• pp.102-113
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• 2023

This review discusses the cellular and molecular mechanisms by which the endometrial estrogen and progesterone receptors regulate local estrogen production, expression of the specific estrogen receptors, progesterone resistance, inflammatory responses and the differentiation and survival of endometriotic cells in endometrial inflammation. The epigenetic aberrations of endometrial stromal cells play an important role in the pathogenesis and progression of endometriosis. In particular, differential methylation of the estrogen receptor genes changes in the stromal cells the dominancy of estrogen receptor from ERα into ERβ, and results in the abnormal estrogen responses including inflammation, progesterone resistance and the disturbance of retinoid synthesis. These stromal cells also stimulate local estrogen production in response to PGE2 and the SF-1 mediated induction of steroidogenic enzyme expression, and the increased estradiol then feeds back into the ERβ to repeat the vicious inflammatory cycle through the activation of COX-2. In addition, high levels of ERβ expression may also change the chromatin structure of endometrial mesenchymal stem cells, and together with the repeated menstrual cycles can induce formation of the endometriotic tissue. The cascade of these serial events then leads to cell adhesion, angiogenesis and survival of the differentiation-disregulated stromal cells through the action of inflammatory factors such as ERβ-mediated estrogen, TNF-α and TGF-β1. Therefore, understanding of the dynamic hormonal changes during the menstrual cycle and the corresponding signal transduction mechanisms of the related nuclear receptors in endometrium would provide new insights for treating inflammatory diseases such as the endometriosis.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.75-87
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• 1996

This review is presented under the following headings: 1.Introduction 1.1 Brief review of the properties of AlN 1.2 Historical survey of work on ceramic and single crystal AlN 2.Thermochemical background 3.Crystal growth 4.Doping 5.Potential applications and future work The known properties of AlN which make it of interest for various are discussed briefly. The properties include chemical stability, crystal structure and lattice constants, refractive indices and other optical properties, dielectric constant, surface acoustic wave velocity and thermal conductivity. The history of work in single crystals, thin films and ceramics are outlined and the thermochemistry of AlN reviewed together with some of the relevant properties of aluminium and nitrogen; the problems encountered in growing crystals of AlN are shown to arise directly from these thermochemical relationships. Methods have been reported in the literature for growing AlN crystals from melts, solution and vapour and these methods are compared critically. It is proposed that the only practicable approach to the growth of AlN is by vapour phase methods. All vapour based procedures share the share the same problems: $.$the difficulty of preventing contamination by oxygen & carbon $.$the high bond energy of molecular nitrogen $.$the refractory nature of AlN (melting point~3073K at 100ats.) $.$the high reactivity of Al at high temperatures It is shown that the growth of epitactic layers and polycrystalline layers present additional problems: $.$chemical incompatibility of substrates $.$crystallographic mismatch of substrates $.$thermal mismatch of substrates The result of all these problems is that there is no good substrate material for the growth of AlN layers. Organometallic precursors which contain an Al-N bond have been used recently to deposit AlN layers but organometallic precursors gave the disadvantage of giving significant carbon contamination. Organometallic precursors which contain an Al-N bound have been used recently to deposit AlN layers but organometallic precursors have the disadvantage of giving significant carbon contamination. It is conclude that progress in the application of AlN to optical and electronic devices will be made only if considerable effort is devoted to the growth of larges, pure (and particularly, oxygen-free) crystals. Progress in applications of epi-layers and ceramic AlN would almost certainly be assisted also by the availability of more reliable data on the pure material. The essential features of any stategy for the growth of AlN from the vapour are outlined and discussed.

• Journal of The Korean Association For Science Education
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• v.43 no.2
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• pp.99-110
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• 2023

In this study, in order to strengthen the AI utilization competency of pre-service secondary science teachers, a project activity in which pre-service teachers directly create an 'AI-based molecular structure customized learning support tool' by using Google's teachable machine was developed and applied. To this end, the program developed for 26 third-grade pre-service teachers enrolled in the Department of Chemistry Education at H University in Chungcheongbuk-do was applied for 14 sessions during extracurricular activities. Then, the perceptions of 'understanding how AI works', 'efficacy of using AI in science classes', and 'plans to utilize AI in science classes' were investigated. As a result of the study, it was found that the program developed in this study was effective in helping pre-service teachers understand the operating principle of AI technology for machine learning at a basic level and learning how to use it. In addition, the program developed in this study was found to be effective in increasing the efficacy of pre-service teachers for the use of AI in science classes. And it was also found that pre-service teachers recognized the aspect of using AI technology as a new teaching·learning strategy and tool that can help students understand science concepts. Accordingly, it was found that the program developed in this study had a positive impact on pre-service teachers' AI utilization competency reinforcement and perception improvement at the basic level. Implications of this were discussed.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.2
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• pp.94-101
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• 2007

Analysis of population structure of Oncorhynchus keta, the most abundant salmon in the East Sea of Korea, has not been much carried out despite its importance as a fishery resource in the North Pacific. Currently, molecular methods are being applied to stock identification and a method of using single nucleotide polymorphisms (SNPs) is getting more popular. In this study, we analyzed the 720 bp long sequence of the mtDNA COIII-ND3-ND4L region in order to examine genetic similarity-dissimilarity among the Korea chum salmons of each stream and their relationship with the Japan chum salmons. A total of 152 individuals were analyzed, 108 from 3 locations of Korea and 44 from 2 locations of japan, which resulted in as many as 29 different haplotypes. Pairwise $F_{ST}$ and AMOVA tests of the populations show that there is no significant population-level genetic difference among the chum salmons analyzed ($F_{ST}<0.07$). On the other hand, haplotype relationships among the individuals reveal that approximately 25% of the Korea salmons consist genetic lineages independent of Japan salmons and also that a genetic lineage exists in the Puk river and the Namdae river salmons independent of the Wangpi river salmons of Korea.

• Journal of Life Science
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• v.34 no.5
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• pp.356-364
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• 2024

Lymph nodes (LNs) are crucial sites where immune responses are initiated to combat invading pathogens in the body. LNs are organized into distinctive compartments by stromal cells. Stromal cell subsets constitute special niches supporting the trafficking, activation, differentiation, and crosstalk of immune cells in LNs. Fibroblastic reticular cells (FRC) are a type of stromal cell that form the three-dimensional structure networks of the T cell-rich zones in LNs, providing guidance paths for immigrating T lymphocytes. FRCs imprint immune responses by supporting LN architecture, recruiting immune cells, coordinating immune cell crosstalk, and presenting antigens. During inflammation, FRCs exert both spatial and molecular regulation on immune cells through their topological and secretory responses, thereby steering immune responses. Here, we propose a model in which FRCs regulate immune responses through a three-part scheme: setting up, supporting, or suppressing immune responses. FRCs engage in bidirectional interactions that enhance T cell biological efficiency. In addition, FRCs have profound effects on the innate immune response through phagocytosis. Thus, FRCs in LNs act as gatekeepers of immune responses. Overall, this study aims to highlight the emerging roles of FRCs in controlling both innate and adaptive immunity. This collaborative feedback loop mediated by FRCs may help maintain tissue function during inflammatory responses.