• Journal of Species Research
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• 제9권3호
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• pp.198-203
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• 2020

The goal of this study was to isolate and identify wild yeasts from soil samples. The 15 wild yeast strains were isolated from the soil samples collected in Pocheon city, Gyeonggi Province, Korea. Among them, four yeast stains were unrecorded, and 11 yeast stains were previously recorded in Korea. To identify wild yeasts, microbiological characteristics were observed by API 20C AUX kit. Pairwise sequence comparisons of the D1/D2 domain of the 26S rRNA were performed using Basic Local Alignment Search Tool(BLAST). Cell morphology of yeast strains was examined by phase contrast microscope. All strains were oval-shaped and polar budding and positive for assimilation of glucose, 2-keto-ᴅ-gluconate, N-acetyl-ᴅ-glucosamine, ᴅ-maltose and ᴅ-saccharose (sucrose). There is no official report that describes these four yeast species: one strain of the genus Kodamaea in the family Metschnikowiaceae and three strains of the Hannaella in the family Bulleribasidiaceae. Kodamaea ohmeri YI7, Hannaella kunmingensis YP355, Hannaella luteola YP230 and Hannaella oryzae YP366 were recorded in Korea, for the first time.

• 스마트미디어저널
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• 제3권1호
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• pp.22-27
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• 2014

전 세계적으로 석유자원의 고갈로 인해 석유가격의 상승 및 중국, 인도 등 거대개도국의 에너지 수요 폭발로 국내외 에너지환경은 새로운 도전과 변화의 국면에 처해 있다. 그러나 태양광 발전은 기존 발전방식에 비하여 발전 단가가 높고 에너지 밀도가 희박하여 일정한 전력을 이용하기 위해서는 넓은 면적의 태양전지모율 설치 장소가 필요하다. 또한 기상조건 및 자연조건에 절대적인 영향을 받기 때문에 태양광 발전의 효율적인 발전을 위해서는 지리적인 위치와 태양의 위치 등을 고려하여 태양전지모듈이 지속적으로 많은 양의 발전을 할 수 있게 하는 기술이 필요하다. 이에 본 연구에서는 기존 추적 시스템의 문제점을 해결하기 위해 새로운 형태의 태양 추적 시스템을 제안하고자 한다. 또한 제안된 기법의 유용성을 확인하기 위해 제작된 시제품에 알고리즘을 구현하여 실제 실험을 수행하고자 한다.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3697-3702
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• 2010

We demonstrate that vertically aligned carbon nanotubes can be synthesized directly on tantalum substrate via water-assisted chemical vapor deposition and evaluate their properties as electrochemical capacitors. The mean diameter of the carbon nanotubes was $7.1{\pm}1.5\;nm$, and 70% of them had double walls. The intensity ratio of G-band to D-band in Raman spectra was as high as 5, indicating good quality of the carbon nanotubes. Owing to the alignment and low equivalent series resistance, the carbon nanotube based supercapacitors showed good rate performance. Rectangular shape of cyclic voltammogram was maintained even at the scan rate of > 1 V/s in 1 M sulfuric acid aqueous solution. Specific capacitance was well-retained (~94%) even when the discharging current density dramatically increased up to 145 A/g. Consequently, specific power as high as 60 kW/kg was obtained from as-grown carbon nanotubes in aqueous solution. Maximum specific energy of ~20 Wh/kg was obtained when carbon nanotubes were electrochemically oxidized and operated in organic solution. Demonstration of direct synthesis of carbon nanotubes on tantalum current collectors and their applications as supercapacitors could be an invaluable basis for fabrication of high performance carbon nanotube supercapacitors.

• Mycobiology
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• 제43권3호
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• pp.266-271
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• 2015

Several types of yeasts were isolated from wild flowers around Jangseong Lake in Jeollanam-do, Republic of Korea and identified by comparing the nucleotide sequences of the PCR amplicons for the D1/D2 variable domain of the 26S ribosomal DNA using Basic Local Alignment Search Tool (BLAST) analysis. In total, 60 strains from 18 species were isolated, and Pseudozyma spp. (27 strains), which included Pseudozyma rugulosa (7 strains) and Pseudozyma aphidis (6 strains), was dominant species. Among the 60 strains, Bullera coprosmaensis JS00600 represented a newly recorded yeast strain in Korea, and its microbiological characteristics were investigated. The yeast cell has an oval-shaped morphology measuring $1.4{\times}1.7{\mu}m$ in size. Bullera coprosmaensis JS00600 is an asporous yeast that exhibits no pseudomycelium formation. It grew well in vitamin-free medium as well as in yeast extract-malt extract broth and yeast extract-peptone-dextrose (YPD) broth, and it is halotolerant growing in 10% NaCl-containing YPD broth.

• 폴리머
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• 제32권3호
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• pp.290-294
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• 2008

러빙한 고분자 필름이 액정 분자와 증착된 분자의 배향을 유도하는 메커니즘을 이해하고자 $\pi$ 전자들의 공액구조가 주사슬과 곁사슬에 각각 있는 polyimide와 polyyinylcinnamate를 사용하여 필름과 LC 셀을 만들어 편광 UV/Vis 분광실험으로 조사하였다. 러빙한 필름 내에 형성되는 이방성, LC 셀의 액정 방향자, 그리고 종착된 pentacene의 배열방향을 측정하여, 액정배향은 microgroove 영향보다는 분자간 상호작용에 의하여 우선적으로 유도되는 반면에 pentacene 증착의 경우에는 러빙에 의하여 형성된 필름 표면의 microgroove 영향으로 배향이 유도되는 것을 알 수 있었다.

• 한국균학회지
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• 제49권4호
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• pp.545-553
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• 2021

In 2021, seven yeast strains were isolated from earthworm (Eisenia andrei) gut samples collected from the Nanji Water Regeneration Center in Goyang City, Gyeonggi Province, Korea. A total of seven yeasts were isolated, of which three strains have not been previously reported in Korea. To identify the yeasts, pairwise sequence comparisons of large subunit (LSU) rDNA sequences were performed using the basic local alignment search tool (BLAST). Assimilation test and cell morphology analysis were performed using the API 20C AUX kit and phase contrast microscope, respectively. Five of the seven strains were assigned to the genus Candida of the order Saccharomycetales of the class Saccharomycetes, and two to the genus Apiotrichum of the order Trichosporonales of the class Tremellomycetes. The yeast strain Candida sojae E2 belongs to the family Debaryomycetaceae, and Apiotrichum laibachii E8 and A. laibachii E9 belong to the family Trichosporonaceae. All strains were cultured in yeast mold agar for three days and showed different colony forms. C. sojae E2 was round and entire shaped, while A. laibachii E8 and A. laibachii E9 was round and convex shaped. This study focuses on the description of the three yeast strains that have not been officially reported in Korea.

• Journal of Plant Biotechnology
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• 제46권2호
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• pp.79-87
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• 2019

One of wild diploid Solanum species, Solanum chacoense, is one of the excellent resources for potato breeding because it is resistant to several important pathogens, but the species is not sexually compatible with potato (S. tuberosum) causing the limitation of sexual hybridization between S. tuberosum and S. chacoense. Therefore, diverse traits regarding resistance from the species can be introgressed into potato via somatic hybridization. After cell fusion, the identification of fusion products is crucial with molecular markers. In this study, S. chacoense specific markers were developed by comparing the chloroplast genome (cpDNA) sequence of S. chacoense obtained by NGS (next-generation sequencing) technology with those of five other Solanum species. A full length of the cpDNA sequence is 155,532 bp and its structure is similar to other Solanum species. Phylogenetic analysis resulted that S. chacoense is most closely located with S. commersonii. Sequence alignment with cpDNA sequences of six other Solanum species identified two InDels and 37 SNPs specific sequences in S. chacoense. Based on these InDels and SNPs regions, four markers for distingushing S. chacoense from other Solanum species were developed. These results obtained in this research could help breeders select breeding lines and facilitate breeding using S. chacoense in potato breeding.

• Journal of Species Research
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• 제10권4호
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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.

• 대한치과교정학회지
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• 제52권4호
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• pp.298-307
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• 2022

Glossectomy combined with radiotherapy causes different levels of tongue function disorders and leads to severe malocclusion, with poor periodontal status in cancer survivors. Although affected patients require regular access to orthodontic care, special considerations are crucial for treatment planning. This case report describes the satisfactory orthodontic management for the correction of severe dental crowding in a 43-year-old female 6 years after treatment for tongue cancer with total glossectomy combined with radiotherapy, to envision the possibility of orthodontic care for oral cancer survivors. Extraction was performed to correct dental crowding and establish proper occlusion following alignment, after considering the possibility of osteoradionecrosis. Orthodontic mini-implants were used to provide skeletal anchorage required for closure of the extraction space and intrusion of the anterior teeth. The dental crowding was corrected, and Class I occlusal relationship was established after 36 months of treatment. The treatment outcome was sustained after 15 months of retention, and long-term follow-up was recommended.

• Journal of Species Research
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• 제12권3호
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• pp.197-202
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• 2023

The purpose of this study was to isolate and identify wild yeasts from the soil collected in Gwangju and Pocheon City, Gyeonggi Province, Republic of Korea. Among 10 strains, six strains were already reported, but four strains were unrecorded in Republic of Korea. To identify wild yeast strains, pairwise sequence comparisons of the D1/D2 region of the 26S rRNA gene sequence were performed using Basic Local Alignment Search Tool (BLAST). The cell morphologies were observed by phase contrast microscope and assimilation tests were carried out using API 20C AUX kit. The 10 strains were assigned to the phyla Basidiomycota (8 strains) and Ascomycota (2strains). The unrecorded four yeast strains, NH33, NH19, NH20, and YP416, belong to the phylum Basidiomycota and the genera Buckleyzyma, Leucosporidium, Holtermanniales, and Mrakia, respectively. All strains had oval-shaped and polar budding cells. In this research, the morphological and biochemical properties of four unreported yeast species were characterized intensively, which were not officially reported in Korea.