• Structural Engineering and Mechanics
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• v.11 no.5
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• pp.485-502
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• 2001

Modem soft computing methods, such as neural networks, evolutionary models and fuzzy logic, are mainly inspired by the problem solving strategies the biological systems use in nature. As such, the soft computing methods are fundamentally different from the conventional engineering problem solving methods, which are based on mathematics. In the author's opinion, these fundamental differences are the key to the full understanding of the soft computing methods and in the realization of their full potential in engineering applications. The main theme of this paper is to discuss the fundamental differences between the soft computing methods and the mathematically based conventional methods in engineering problems, and to explore the potential of soft computing methods in new ways of formulating and solving the otherwise intractable engineering problems. Inverse problems are identified as a class of particularly difficult engineering problems, and the special capabilities of the soft computing methods in inverse problems are discussed. Soft computing methods are especially suited for engineering design, which can be considered as a special class of inverse problems. Several examples from the research work of the author and his co-workers are presented and discussed to illustrate the main points raised in this paper.

• The Plant Pathology Journal
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• v.24 no.1
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• pp.24-30
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• 2008

Colletotrichum gloeosporioides forms an appressorium, a specialized infection structure, to infect its hosts. Among 400 and 600 culture filtrates from fungi and class Actinomycetes, six methanol extracts (A5005, A5314, A5387, A5560, A5597, and A5598) from the class Actinomycetes significantly inhibited appressorium formation in C. gloeosporioides infecting pepper fruits in a dose-dependent manner, while conidial germination was slightly enhanced. Two (A5005 and A5560) of them also exhibited distinctive inhibitory effect on the disease progress of pepper anthracnose. Water fractions of both culture filtrates also specifically inhibited appressorium formation in C. gloeosporioides and pepper anthracnose disease. Inhibition of appressorium formation by culture filtrate of A5005 was partially restored by the exogenous calcium. This results suggests that chemicals within A5005 extents its biological activity through disturbance of intracellular $Ca^{2+}$ regulation during prepenetration morphogenesis by C. gloeosporioides. Together, cell-based and target-oriented screening system used in this study should be applicable for other plant pathogenic fungi prerequisite appressorium formation to infect their hosts.

• Journal of Chest Surgery
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• v.26 no.11
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• pp.827-832
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• 1993

From Jan 1982 through Dec.1991, thirty-three DeVega`s tricuspid annuloplasties were performed in association with mitral and combined mitral and aortic valve disease. Preoperatively,all of the patients were in NYHA functional class III or IV.There were one early death and 4 patients died during follow up period of 18 to 138 months [ mean follow up : 67.3 months ]. Nine patients required reoperation because of biological mitral valve failure at 4.7 to 11 years after tricuspid annuloplasty[TAP]. Among these patients,2 cases needed for reoperation of TAP due to loosening of suture material. Twenty four [86%] of the survivors were in NYHA functional class I or II after TAP.The actuarial survival rate for the TAP was 74% at 138 months. Rt atrial pressure of 9 reoperation cases were significantly decreased [P<0.05] compared with initial Rt.atrial pressure [ Mean period; 93.6 months].Doppler echocardiographic studies for tricuspid regurgitation were performed in 15 cases after TAP [Mean period: 42.3 months].These results showed significantly reduced [P<0.01] tricuspid annulus diameter and tricuspid regurgitation distance [ P<0.05 ].Our surgical experience that the DeVega`s TAP is a simple,safe,effective procedure and resulted in good hemodynamic improvement with moderate to severe functional tricuspid regurgitation.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.447-456
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• 1995

As a part of electro-mechanical totally implantable artificial heart (TIAH) program, a transcut- aneous energy transmission system has been developed. By mutual magnetic induction between the first coil on the skin and the subcutaneously implanted second coil, the system transfers elctrical power through the skin. This research aimed at minimizing the size of the implanted part as well as maximizing the transfer efficiency. Using class I amplifier, we achieved above 75% power transfer efficiency at average 40W power transfer level which is required for normal TIAH operation. In vivo performance of the developed system and bio-compatibility of the material used in Implanted parts were evaluated through animal experiments.

• Restorative Dentistry and Endodontics
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• v.42 no.3
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• pp.240-252
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• 2017

The restoration of endodontic tooth is always a challenge for the clinician, not only due to excessive loss of tooth structure but also invasion of the biological width due to large decayed lesions. In this paper, the 7 most common clinical scenarios in molars with class II lesions ever deeper were examined. This includes both the type of restoration (direct or indirect) and the management of the cavity margin, such as the need for deep margin elevation (DME) or crown lengthening. It is necessary to have the DME when the healthy tooth remnant is in the sulcus or at the epithelium level. For caries that reaches the connective tissue or the bone crest, crown lengthening is required. Endocrowns are a good treatment option in the endodontically treated tooth when the loss of structure is advanced.

• Journal of Species Research
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• v.8 no.4
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• pp.351-364
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• 2019

Here we describe indigenous prokaryotic species in Korea, a total of 42 bacterial strains affiliated to the class Alphaproteobacteria isolated from various environmental samples: fermented vinegar, sea water, beach sand, fresh water, salt flats, moss, algae, activated sludge, and soil. From the high 16S rRNA gene sequence similarity (>98.7%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to predefined bacterial species. There is no official report that these 42 species included in Alphaproteobacteria in Korea: 15 species of 6 genera in the order Rhodospirillales, 12 species of 10 genera in the order Rhizobiales, 10 species of 8 genera in the order Rhodobacterales, 4 species of 4 genera in the order Sphingomonadales and 1 species of 1 genus in the order Caulobacterales. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section.

• Journal of Species Research
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• v.10 no.4
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• pp.350-355
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• 2021

In 2020, 11 Basidiomycetous yeast strains were isolated from soil samples collected from the forests of Namhansanseong in Korea. Among them, seven species were reported, but four species were unreported in Korea. To identify wild yeasts, pairwise sequence comparisons of D1/D2 domain of the 26S rRNA were performed using Basic Local Alignment Search Tool (BLAST). The cell morphologies and assimilation test are observed by phase contrast microscope and API 20C AUX kit, respectively. The 11 strains were assigned to the genera Rhodotorula (4 strains) of the order Sporidiobolales of the class Microbotryomycetes; and Cryptococcus(2 strains), Goffeauzyma (1 strains), Naganishia (2 strains) of the order Filobasidiales and Saitozyma (2 strains) of the order Tremellales of the class Tremellomycetes in the phylum Basidiomycota. The unreported yeast strains Cryptococcus gastricus 20n5-2, Goffeauzyma gilvescens 20n2-7, Naganishia adeliensis 20n8-1, and Naganishia friedmannii 20n24-1 belong to the family Filobasidiaceae. All strains had oval shaped cells and cream-colored colonies cultured on on YM agar for 3 days. In this study, we focus on the description of four unreported yeast species in Korea.

• Mass Spectrometry Letters
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• v.13 no.4
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• pp.158-165
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• 2022

Many therapeutic class drugs such as beta-blocker, corticosteroids, NSAIDs, etc are prohibited substances in the horse racing industry. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology makes it possible to isolate drugs from interference, enables various drug analyses in complex biological samples due to its sensitive sensitivity, and has been successfully applied to doping control. In this paper, we describe a rapid and sensitive method based on solid-phase extraction (SPE) using solid phase cartridge and LC-MS/MS to screen for different class's 35 drug targets in equine plasma. Plasma samples were pretreated by SPE with the NEXUS cartridge consisted non-polar carbon resin and minimum buffer solvent. Chromatographic separation of the analytes was performed on ACQUITY HSS C18 column (2.1 × 150 mm, 1.8 ㎛). The elution gradient was conducted with 5 mM ammonium formate (pH 3.0) in distilled water and 0.1% formic acid in acetonitrile at a flow rate of 0.25 mL/min. The selected reaction monitoring (SRM) mode was used for drug screening with multiple transitions in the positive ionization mode. The specificity, limit of detection, recovery, and stability was evaluated for validation. The method was found to be sensitive and reproducible for drug screening. The method was applied to plasma sample analysis for the proficiency test from the Association of Racing Chemist.

• Journal of Species Research
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• v.12 no.3
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• pp.212-223
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• 2023

A total of 30 bacterial strains were identified in the classes Betaproteobacteria and Gammaproteobacteria in the study of prokaryotic species in Korea. These strains were isolated from a variety of environmental sources, including soil, tidal flat, mud, wetland, pine cone, seaweed, sea sediment, and brackish water. Phylogenetic analysis showed that isolates were identified based on high 16S rRNA gene sequence similarities (≥98.7%) with the predefined bacterial type species. In this study, we present data on previously unreported species from Korea, including 10 species from three families of one order in the class Betaproteobacteria and 20 species from 12 families of nine order in the class Gammaproteobacteria. Morphological, biochemical characteristics, isolation sources, and NIBR deposit numbers are provided in the description sections.

• Food Science of Animal Resources
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• v.43 no.4
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• pp.625-638
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• 2023

Among various biological agents, bacteriocins are important candidates to control Listeria monocytogenes which is a foodborne pathogen. In this study, a novel bacteriocin, named agilicin C7, was isolated from Ligilactobacillus agilis C7 showing inhibitory activity against L. monocytogenes. Agilicin C7 biosynthesis gene was characterized by bioinformatics analyses and heterologously expressed in Escherichia coli for further study. The anti-listeria activity of recombinant agilicin C7 (r-agilicin C7) was lost by proteases and α-amylase, suggesting that agilicin C7 is a glycoprotein. r-Agilicin C7 has wide pH and thermal stability and is also stable in various organic solvents. It destroyed L. monocytogenes by damaging the integrity of the cell envelope. These properties of r-agilicin C7 indicate that agilicin C7 is a novel amylase-sensitive anti-listerial Class IId bacteriocin. Physicochemical stability and inhibitory activity against L. monocytogenes of r-agilicin C7 suggest that it can be applied to control L. monocytogenes in the food industry, including dairy and meat products.