• The Korean Journal of Mycology
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• v.42 no.3
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• pp.239-242
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• 2014

In this study, endophytic fungi were isolated from leaves of four species of woody plants, Acer tagmentosum, Larix kaempferi, Abies holophylla, and Pinus koraiensis, on Mt. Hambaek, Gangwondo, Korea. The endophytic fungi were identified using morphological and sequences analysis of ITS regions. The fungal endophytes were identified as Talaromyces radicus, Myceliophthora verrucosa, Cryptosporiopsis diversispora, and Sphaerulina berberidis, which are the first record in Korea. The morphological and molecular phylogenetic characteristics of each strain were described.

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.140-144
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• 2006

This study was performed to investigate the effect of organic characteristics and feed water solution chemistry on membrane fouling index such as Silt Density Index (SDI) and Modified Fouling Index (MFI). Specifically, Aldrich humic acids (AHA) and Suwannee river humic acids (SHA) were used in SDI/MFI experiments. Higher SDI values were observed with increasing organic concentration. AHA with larger molecular weight (MW) and SUVA (${\approx}UV_{254}/TOC$) resulted in higher SDI values, compared to SHA. The feed solution chemistry (i.e, pH, ionic strength, and hardness) also affects SDI values to some degree. In particular, SDI increased with increasing hardness ($Ca^{2+}$) concentration for AHA. Unlike SDI, the MFI developed on the basis of particle cake filtration theory, was not accurately assessed due to internal fouling by organics such as pore adsorption and subsequent pore blocking.

• Journal of the Korean Wood Science and Technology
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• v.20 no.2
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• pp.81-90
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• 1992

The effect of acid treatment of cellulose on the substitution charateristics of carboxymethylation was studied in this paper. Five samples of hydrocellulose(HC), all prepared from ${\alpha}$-cellulose by hydrolysis with five reaction times and determined on average molecular weight and polydispersity, were carboxymethylated to carboxymethyl cellulose (CMC). The CMCs from HCs were examined upon degree of substitution(DS), distribution of carboxymethyl groups in anhydroglucose units of the cellulose, and unsubstituted anhydroglucose(USAG) content. The DS of CMCs increased with increasing the hydrolysis time except CMC from HC at 1 hour hydrolysis time. In carboxymethylation the availability of hydroxyl groups on anhydroglucose units in HCs was the highest on OH(2), and the relative availability of OH(6) increased with the increasing of the hydrolysis time. The USAG contents were more deviated than that calculated based on Spurlin's model, and had a strong tendency of decreasing with increasing the hydrolysis time. The reactivity of HC was lower than that of ${\alpha}$-cellulose and the relative availability of OH(6) in HC increased with the hydrolysis time.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.4
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• pp.238-244
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• 2007

Nowadays many people are concerned about being healthy, and many dairy products are taken as health supplementary foods. Among dairy products, kefir, also called as Tibet mushroom, is a yogurt fermented by kefir grain, which is a mixture of lactic acid bacteria and yeasts. Although there are many empirical evidences that kefir is very influential for human body, the exact reason is not definitively discovered. Therefore, it would be useful to understand characteristics of a kefir grain and to categorize bacteria in a kefir grain. In this paper, molecular biological apparatus such as PCR, electrophoresis, PCR purification, DNA sequencing were used to identify and classify the species of lactic acid bacteria and yeast in a kefir grain. We used PCR-based identification method using 16S rRNA primer and Internal Transcribed Spacer (ITS) primer. We identified 6 different species which were selected on different medium. In addition, observation with scanning electron microscope (SEM) enabled us to grasp an external shape of the kefir grain. Although we found a limited number of microbial species, more intensive research are needed for extensive identification of microorganism species in Korean kefir grain.

• Membrane Journal
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• v.22 no.5
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• pp.352-358
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• 2012

In this study, we found structure-property relationship for pressure retarded osmosis (PRO) membrane, between BPS-XX and BisA-XX having similar structure but different free volume. And this comparison was subdivided by controlling its sulfonation degree. BPS-XX and BisA-XX were prepared via a polycondensation reaction. The degree of sulfonation were 20 to 60 mol.%. And they were fabricated to membrane. Characteristics were analyzed to verify of free volume. And the results showed that increase of free volume normally lead to increase permeability and decrease selectivity in equivalent molecule structure. Finally, in the permeability-selectivity results, we conclude high permeability and selectivity membrane can be prepared by controlling molecular structure and free volume.

• Journal of Microbiology
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• v.44 no.2
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• pp.145-154
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• 2006

Heterotrimeric G proteins (G proteins) are conserved in all eukaryotes and are crucial components sensing and relaying external cues into the cells to elicit appropriate physiological and biochemical responses. Basic units of the heterotrimeric G protein signaling system include a G protein-coupled receptor (GPCR), a G protein composed of ${\alpha},\;{\beta},\;and\;{\gamma}$ subunits, and variety of effectors. Sequential sensitization and activation of these G protein elements translates external signals into gene expression changes, resulting in appropriate cellular behaviors. Regulators of G protein signaling (RGSs) constitute a crucial element of appropriate control of the intensity and duration of G protein signaling. For the past decade, G protein signaling and its regulation have been intensively studied in a number of model and/or pathogenic fungi and outcomes of the studies provided better understanding on the upstream regulation of vegetative growth, mating, development, virulence/pathogenicity establishment, and biosynthesis of secondary metabolites in fungi. This review focuses on the characteristics of the basic upstream G protein components and RGS proteins, and their roles controlling various aspects of biological processes in the model filamentous ascomycete fungus Aspergillus nidulans. In particular, their functions in controlling hyphal proliferation, asexual spore formation, sexual fruiting, and the mycotoxin sterigmatocystin production are discussed.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1268-1270
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• 1994

Fine lithographic technology in a submicron design regime is necessary for the fabrication of VLSI circuits. In such lithography, fine pattern delineation is performed by electron beam, ion beam and X-ray lithography instead of photolithography. Therefore, the new resist materials and development method have been required. So, we are investigating another positive E-beam resists which have high sensitivity and dry etching resistance, Plasma co-polymerized resist was prepared using an interelectrode gas-flow-type reacter. Methymethacrylate, tetramethyltin and styrene were chosen as the monomer to be used. The delineated pattern in the resist was developed with gas-flow-type reactor using an argon and 02 as etching gas. We studied about the effects of discharge power and mixing rate of the co-polymerized thin :film. The molecular structure of thin film was investigated by ESCA and IR, and then was discussed in relation to its quality as a resist.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.470-499
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• 1998

For the purpose of designing more successful cancer research, the strategy for cancer study in the field of Traditional Korean Medicine(TKM) during the 21th century was examined from the analysis of trends on cancer study in traditional korean medicine. The results were summarized as follows: 1. So far cancer research in TKM was chiefly done on cytotoxicity, side-effects by chemotherapy, tumor immunology, apoptosis, survival time with S-180 and pulmonary colonization assay and also clonogenic assay, cell adhesion assay, angiogenesis, cell-differentiation and side-effect by radiotherapy were partly performed. 2. It may be ideal that we should study synergistic effect between constituent drugs of prescriptions, tumor immunology, combined therapy between western and oriental medicines by reducing side-effect by radiotherapy and chemotherapy and antimetastasis according to the characteristics of oriental medicine chiefly and also supplement the studies on molecular biology, gene therapy, angiogensis and signal transduction. 3. We had better do specific-field research in cooperation between oriental medical colleges and Korea Institute of Oriental Medicine(KIOM) as well as study a target cancers such as hepatic cancer, pulmonary cancer and gastric cancer more intensively than all cancers domestically. 4. Our country must keep communication with China having many clinical data, Taiwan chiefly doing the combined tharapy between oriental and western medicines, Japan having done basic study actively on cancer.

• Journal of Conservation Science
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• v.34 no.2
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• pp.129-135
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• 2018

Scientific investigation of cultural heritage can provide important information to understand the context of the object. To know the characteristics of the material is also an essential part of objects management and conservation. However, the identification and characterization of organic dyes used in archaeological and historical textiles are often limited by the restrictions in sampling. To cope with the difficulties, applications of high-performance techniques of surface analysis, such as Time of Flight-Secondary Ion Mass Spectra (TOF-SIMS) could be considered as a non or micro-destructive option. This study aims to examine the applicability of TOF-SIMS analysis to the detection of organic dyes from historical textiles. A group of silk fabrics dyed with vegetable dyes were artificially photo-aged to different degrees and analyzed with TOF-SIMS. Molecular and fragment ions from indigo were successfully detected from the aged samples; however, only some fragment ions were observed from gardenia and safflower dyed fabrics. Further studies with actual historical samples with extended examination scope would be necessary to assess the validity of this technique.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.393-397
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• 1988

The adenylate kinase was purified from an extreme thermophile by adenosine-pentaphospho-adenosine elution from phosphocellulose column. The molecular weight was estimated to be 22,000 by SDS-PAGE and gel filtration. The optimum temperature of the enzyme activity was 8$0^{\circ}C$ and the activation energy was given as 22.4 kcal/mole. The enzyme even showed full activity after incubation at 9$0^{\circ}C$ or in 6M guanidine-HCI at 3$0^{\circ}C$ and retained 75% of its original activity even after 1 hour at 10$0^{\circ}C$. The Michaelis constants of the enzymes for AMP, ADP, and ATP were 0.01mM, 0.017mM and 0.067mM, respectively.