• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.35.2-35.2
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• 2021

Blue straggler stars (BSs) are "rejuvenated" main sequence stars first recognized by Allan Sandage from his observation of the prominent northern globular cluster M3 in the year of 1953. BSs are now known to be present in diverse stellar environments including open clusters, globular clusters, dwarf galaxies, and even the field populations of the Milky Way. This makes them a very useful tool in a wide range of astrophysical applications: Particularly BSs are considered to have a crucial role in the evolution of stellar clusters because they affect on the dynamics, the binary population, and the history of the stellar evolution of the cluster they belong to. Here we report a part of the preliminary results from our ongoing research on the BSs in the two metal-poor globular clusters (GCs) in the Large Magellanic Cloud (LMC), Hodge 11 and NGC1466. Using the high precision multi-band images obtained with the Advanced Camera for Survey (ACS) onboard the Hubble Space Telescope (HST), we extract time-series photometry to search for the signal of periodic variations in the luminosity of the BSs. Our preliminary results confirm that several BSs are intrinsic "short period (0.05 < P < 0.25 days)" variable stars with either pulsating or eclipsing types. We will discuss our investigation on the properties of those variable BS candidates in the context of the formation channels of these exotic main sequence stars, and their roles in the dynamical evolution of the host star clusters.

• Journal of architectural history
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• v.7 no.3 s.16
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• pp.87-105
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• 1998

Surveying the literature of architecture since the nineteenth century, one can identify two dominant but problematic attitudes, among several, that pursue the task of defining what modern architecture is and should be. The first is the search for meaning and the second is the pursuit of form. This study, following Michel Foucault, asserts that the dual formation of meaning and form is a historical product of modernity and belies architecture's uncritical dependence on language since the nineteenth century. This study is a critique and historical analysis of this pernicious reliance, and constitutes a first step towards thinking of alternative relations between 'words and architecture' in the modern world. In reconstructing this problematic, the paper has called on Foucault's seminal The Order of Things. The study follows his construction of the Renaissance, the Classical and the Modern episteme, and in brief fashion, reconstructs the relation between language and architecture in each episteme. In analysing the Modern, the study focuses on Hegel's Lectures on Aesthetics. Hegel placed architecture in a genre hierarchy within which architecture, because of its material basis, was fundamentally limited in its ability to express the Spirit. For Hegel it was, among the arts, poetic language, and beyond art, the language of philosophy, through which the Absolute Spirit could be atttained. Much of post-nineteenth century architecture has remained within the shadow of Hegel, where architecture's materiality is perceived to be a burden, and in order to secure its relevance in modern society, architecture was deemed to pursue the role of language. As the most recent and sophisticated example of architecture's pursuit of form, the paper analyses the work of Peter Eisenman. Though Eisenman's theoretical writings are replete with post-Hegelian rhetoric, his architecture remains dependent upon the model of language, albeit a structuralist one. The paper concludes that ultimately, the pursuit of meaning and form is unable to face the crucial issue of value in modernity. While the former decides to easily what it is, the latter evades the issue itself. The second installment of this ongoing study will pursue a third possibility alluded to by Foucault, where language remains silent, pointing only to its 'ponderous' material existence.

• Korean Journal of Medicinal Crop Science
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• v.20 no.4
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• pp.222-230
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• 2012

We evaluated the inhibitory effects of extracts and components of Geranium thunbergii on aldose reductase (AR) and galactitol formation in rat lenses with high levels of galactose as a part of our ongoing search of natural sources for therapeutic and preventive agents for diabetic complications. The inhibitory effects of water, methanol and ethanol extracts of G. thunbergii on rat lens AR (RLAR) were determined. Comparing inhibitory effects of various solvent extracts, ethanol extract showed RLAR inhibitory activity ($IC_{50}$ values, 5.24 and $6.39{\mu}g/m{\ell}$, respectively). The ethanol extract was fractionated to chloroform, ethyl acetate and water. Of these, the ethyl acetate fraction from ethanol extract of G. thunbergii exhibited RLAR inhibitory activity ($IC_{50}$ value, $2.64{\mu}g/m{\ell}$). In order to identify the bioactive components of ethyl acetate soluble fraction of ethanol extract from G. thunbergii, eight compounds, namely gallic acid (1), protocatechuic acid (2), p-hydroxybenzoic acid (3), brevifolin carboxylic acid (4), geraniin (5), ellagic acid (6), kaempferol-3-O-arabinofuranosyl-7-O-rhamnopyranoside (7), kaempferitrin (8) were isolated. The isolates were subjected to in vitro bioassays to evaluate their inhibitory activity on RLAR and galactitol formation in rat lenses. The ellagic tannins (5, 6) and flavonoid (7) exhibited strong inhibitory effects on RLAR. Also, these three compounds (5, 6 and 7) suppressed galactitol accumulation in rat lens under high galactose conditions, demonstrating the potential to prevent galactitol accumulation exo vivo. These results suggest that the extracts and components of G. thunbergii are a promising agent in the prevention or treatment of diabetic complications.

• The Journal of the Korea Contents Association
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• v.11 no.1
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• pp.387-395
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• 2011

This research the impacts of the tourism motivation and tourism product experimentiality to the korea national image and the results are as follow. First, chinese tourist' on korean wave showed sensory experiences of experiential marketing, emotional experience, cognitive experiences positively affect to the festival brand loyalty. Second, it showed all items of sensory experiences of experiential marketing, emotional experience, cognitive experiences positively affect to the festival brand loyalty. Through these results, first, Necessity is the possibility of knowing the thing there was grasp about tourism motive difference of the cold Chinese tourists' on korean wave. Second, there must be to cold current tourism goods development, must provide the possibility of knowing the thing was an experience characteristic to the tourists. With this character direction, presented a ongoing search that cold current korean wave tourism market measurement from governmental dimension, cold korean wave tourism goods development which applies the contents from enterprise dimension, theoretical foundation data triangular position from scientific dimension.

• Natural Product Sciences
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• v.21 no.3
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• pp.162-169
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• 2015

Hamamelis japonica (Hamamelidaceae), widely known as Japanese witch hazel, is a deciduous flowering shrub that produces compact clumps of yellow or orange-red flowers with long and thin petals. As a part of our ongoing search for phenolic constituents from this plant, eleven phenolic constituents including six flavonol glycosides, a chalcone glycoside, two coumaroyl flavonol glycosides and two galloylated compounds were isolated from the flowers. Their structures were elucidated as methyl gallate (1), myricitrin (2), hyperoside (3), isoquercitrin (4), quercitrin (5), spiraeoside (6), kaempferol 4'-O-β-glucopyranoside (7), chalcononaringenin 2'-O-β-glucopyranoside (8), trans-tiliroside (9), cis-tiliroside (10), and pentagalloyl-O-β-D-glucose (11), respectively. These structures of the compounds were identified on the basis of spectroscopic studies including the on-line LCNMR-MS and conventional NMR techniques. Particularly, directly coupled LC-NMR-MS afforded sufficient structural information rapidly to identify three flavonol glycosides (2 - 4) with the same molecular weight in an extract of Hamamelis japonica flowers without laborious fractionation and purification step. Cytotoxic effects of all the isolated phenolic compounds were evaluated on HCT116 human colon cancer cells, and pentagalloyl-O-β-D-glucose (11) was found to be significantly potent in inhibiting cancer cell growth.

• Archives of Pharmacal Research
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• v.29 no.8
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• pp.617-623
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• 2006

In our ongoing search for bioactive compounds originating from the endemic species in Korea, we found that the hexane and EtOAc fractions of the MeOH extract from the root of Dystaenia takeshimana (Nakai) Kitagawa (Umbelliferae) showed cyclooxygenase-2 (COX-2) and 5- lipoxygenase (5-LOX) dual inhibitory activity by assessing their effects on the production of prostaglandin $D_2\;(PGD_2)$ and leukotriene $C_4\;(LTC_4)$ in mouse bone marrow-derived mast cells. By activity-guided fractionation, five coumarins, viz. psoralen (2), xanthotoxin (3), scopoletin (4), umbelliferone (5), and (+)-marmesin (6), together with ${\beta}-sitosterol$ (1), were isolated from the hexane fraction, and two phenethyl alcohol derivatives, viz. 2-methoxy-2-(4'-hydroxyphenyl)ethanol (7) and 2-hydroxy-2-(4'-hydroxyphenyl)ethanol (8), three flavonoids, viz. apigenin (9), luteolin (10), and cynaroside (11), as well as daucosterol (12) were isolated from the EtOAc fraction using silica gel column chromatography. In addition, D-mannitol (13) was isolated from the BuOH fraction by recrystallization. Two of the coumarins, scopoletin (4) and (+)- marmesin (6), the two phenethyl alcohol derivatives (7, 8) and the three flavonoids (9-11) were isolated for the first time from this plant. Among the compounds isolated from this plant, the five coumarins as well as the three flavonoids showed COX-2/5-LOX dual inhibitory activity. These results suggest that the anti-inflammatory activity of D. takeshimana might in part occur via the inhibition of the generation of eicosanoids.

• Mycobiology
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• v.49 no.4
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• pp.434-437
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• 2021

In our ongoing search for new secondary metabolites from fungi, a basidiomycete fungus Irpex consors was selected for mycochemical investigation, and three new zwitterionic alkaloids (1-3) and five known compounds (4-8) were isolated from the culture broth (16 l) of I. consors. The culture filtrate was fractionated by a series of column chromatography including Diaion HP-20, silica gel, and Sephadex LH-20, Sep-Pak C₁₈ cartridge, medium pressure liquid chromatography (MPLC), and high pressure liquid chromatography (HPLC) to yield eight compounds (1-8). The structures of the isolated compounds were elucidated by the interpretation of nuclear magnetic resonance (NMR) spectra and high-resolution mass spectrometry (HR-MS). Their antioxidant and antibacterial activities were examined. The zwitterionic structures of three new sesquiterpene alkaloids (1-3) were determined together with five known compounds identified as stereumamide E (4), stereumamide G (5), stereumamide H (6), stereumamide D (7), and sterostrein H (8). This is the first report of the zwitterionic alkaloids in the culture broth of I. consors. Three new zwitterionic alkaloids were named as consoramides A-C (1-3).

• Journal of dental hygiene science
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• v.21 no.1
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• pp.1-7
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• 2021

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted primarily through droplets, and dental practitioners are at risk of occupational exposure to SARS-CoV-2 infection owing to direct contact with the patient's mouth, aerosols from dental procedures, and saliva. Wearing a mask is believed to be the best method of protection against infection, and a systematic literature review was conducted on whether the dental masks used in dentistry are effective in preventing Coronavirus Infectious Disease-19 (COVID-19). Methods: We used PubMed, Google Scholar, DBpia, NDSL, and KISS databases for this study. Of the 917 documents narrowed down by the search terms "Coronavirus, COVID-19, and dental," 83 documents were collected and studied. Ultimately, 42 of these papers were selected for analysis after considering duplication from the flow chart of the literature selection process. Results: While dental masks are often used when treating patients with unknown COVID-19 status, the Ministry of Food and Drug Safety stated that the use of dental masks is insufficient in preventing cross-transmission of COVID-19; instead, it was recommended that N95 masks, which correspond to KF94 masks, should be worn daily. On the other hand, wearing a dental mask and following precautions such as hand hygiene may not pose a significantly higher risk of infection than wearing an N95 mask when treating COVID-19 patients. Conclusion: There is an ongoing discussion regarding the use of dental masks when treating dental patients, and many argue that different types of masks should be selected according to the degree of infection and the individual's respiratory condition. By considering the safety and efficacy of dental masks in preventing infection, improvements can be made in the management of COVID-19 and dental-related infections.

• Journal of Dental Anesthesia and Pain Medicine
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• v.22 no.1
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• pp.1-10
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• 2022

Background: Inferior alveolar nerve block (IANB) is known to have a lower success rate for anesthesia in patients with irreversible pulpitis. This calls for supplementary techniques to effectively anesthetize such patients. This systematic review aimed to evaluate the published literature for determining the success rate of anesthesia induction using post-IANB intraligamentary (IL) injection in the mandibular teeth of patients with symptomatic irreversible pulpitis. The review question was, "What is the success rate of IL injection in the mandibular teeth of patients with irreversible pulpitis as a supplementary technique for endodontic treatment?" Methods: A thorough search of electronic databases and manual searches were performed. The protocol of the review was framed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and was registered in the International Prospective Register of Ongoing Systematic Reviews (PROSPERO) with a proper criterion for inclusion and exclusion of studies. The included studies were analyzed using the Cochrane Collaboration "Risk of Bias" tool. A meta-analysis that included a comparison of primary nerve block and supplemental IL injection was performed. The success rate was evaluated using the combined risk ratio (RR) with a random risk model. A funnel plot was created to measure publication bias. Results: After all analyses, four studies were included. In the forest plot representation, RRs were 3.56 (95% CI: 2.86, 4.44), which were in favor of the supplemental IL injections. Statistical heterogeneity was found to be 0%. These values suggest that supplemental IL injections provide better success rates for anesthesia. Conclusion: According to the pooled qualitative and quantitative analyses, supplemental IL injections increased anesthetic efficacy.

• Mycobiology
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• v.49 no.6
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• pp.604-606
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• 2021

In our ongoing search for new secondary metabolites from fungal strains, one novel compound (1) and nine known compounds (2-10) were isolated from the EtOAc-soluble layer of the culture broth of Panus rudis. The culture broth of P. rudis was extracted in acetone and fractionated by solvent partition; column chromatography using silica gel, Sephadex LH-20, and Sephadex G-10; MPLC; and HPLC. The structures of isolated compounds were elucidated by one- and two-dimensional NMR and LC-ESI-mass measurements. One new compound, panepoxydiol (1), and nine known compounds, (E)-3-(3-hydroxy-3-methylbut-1-en-1-yl)-7-oxabicyclo[4.1.0]hept-3-ene-2,5-diol (2), isopanepoxydone (3), neopanepoxydone (4), panepoxydone (5), panepophenanthrin (6), 4-hydroxy-2,2-dimethyl-6-methoxychromane (7), 6-hydroxy-2,2-dimethyl-3-chromen (8), 2,2-dimethyl-6-methoxychroman-4-one (9), 3,4-dihydroxy-2,2-dimethyl-6-methoxychromane (10), were isolated from the culture broth of P. rudis. This is the first report of isolation of a new compound panepoxydiol (1) and nine other chemical constituents (2-5, 7-10) from the culture broth of P. rudis.