• Mycobiology
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• 제42권3호
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• pp.291-295
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• 2014

Mycoflora was assessed in the commercial meju from four well-separated geographic origins. A total of 112 fungal isolates were identified by phenotypic characteristics and molecular taxonomy using sequencing the internal transcribed spacer of the rDNA and revealed 19 species from 13 genera. Enzymatic characteristics of protease and amylase, and mycotoxin production were analyzed.

• BMB Reports
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• 제30권2호
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• pp.157-161
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• 1997

The present paper reports characteristics and specificity of the inhibitory action of $N^{\alpha}-tosyl-L-lysine-chloromethyl\;ketone$ (TLCK) and $N^{\alpha}-tosyl-L-phenylalanine-chloromethyl\;ketone$ (TPCK) on the glucose6-phosphate transporter of rat liver microsomes. The TLCK-induced inhibition was pH dependent. The inhibition constants for TPCK were determined by following pseudo-Lst order reaction mechanism. The inhibition was protected by preincubation with excess amount of glucose-6-phosphate. The results proved that (a) TLCK inactivates the microsomal glucose-6-phosphate transporter, (b) the inhibition results from the modification of sulfhydryl groups of the transporter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1262-1264
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• 1994

Effects of molecular characteristics such as melt index and shapes of molecular weight distribution on the charge formation in LDPE have been investigated. Both homocharge and heterocharge were observed in LDPE depending on the value of melt index. It was found that the LDPE having intermediate melt indices shows heterocharge while the LDPE having small and high melt indecies shows homocharge. The shapes of molecular weight distributions were also found to affect the space charge in LDPE. These were explained by the role of short chains having low molecular weight in LDPE.

• 한국물환경학회지
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• 제21권2호
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• pp.125-131
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• 2005

Natural organic matter(NOM) is defined as the complex matrix of organic material and abundant in natural waters. It affects the performance of unit operations for water purification. Several kinds of analytical indicators such as DOC, specific ultraviolet absorbance(SUVA), apparent molecular weight (AMW), fractionation and high performance size exclusive chromatography(HPSEC) have been used to understand characteristics and variations of NOM. This study aims to evaluate the characteristics of NOM in the Geum River system comprising with stream flows and reservoirs. It was identified that SUVA denoting the portion of humic substance in water ranged within 1.60~3.36. Using resin adsorbents, dissolved organic carbon(DOC) was fractionated into three classes: hydrophobic bases(HOB), hydrophobic acids(HOA) and hydrophilic substances(HI). HI dominates in all samples, collectively accounting for more than 62% of the DOC. HOA was the second dominated fraction and it varied considerably but accounted for about 30% of the DOC. The distribution of high molecular weight(HMW) measured by HPSEC being used to determine the molecular weight distribution of aquatic humic substances was 40.1% and 38.7% in reservoir and stream flow, respectively. The distribution of low molecular weight(LMW) in stream flow was 13.2% higher than that in reservoir. And apparent molecular weight less than 1KDa, which include the molecular weight of hydrophilic organic matter, occupied with 69.2% and 68.2% in stream flow and reservoir, respectively. While the molecular weight of 1 to 100 KDa including humic substances ranged with 18.6% and 21.6% in stream flow and reservoir, respectively. Seasonal variation of refractory dissolved organic carbon was similar to that of SUVA.

• 한국축산식품학회지
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• 제31권6호
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• pp.886-892
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• 2011

This study investigated the ACE-inhibitory effect of yogurt beverage fortified with hydrolysates as well as the suitability of hydrolysates as a nutraceutical additive to yogurt beverage. Three whey protein hydrolysates hydrolyzed by alcalase, protamex, and trypsin were each added to yogurt beverage at concentrations of 1.25, 2.5, and 5 mg/mL. Yogurt beverage fortified with 2.5 mg/mL of hydrolysates had 61-69% ACE-inhibitory activity, whereas yogurt beverage fortified with 5 mg/mL of hydrolysates showed 74% ACE-inhibitory activity. There were no significant differences in ACE-inhibitory activity between the alcalase or protamex hydrolysates during storage; however, trypsin hydrolysate exhibited significant differences. On the other hand, physicochemical characteristics such as pH (3.47-3.77), titratable acidity (0.81-0.84%), colority, viable cell count, and sensory qualities were not significantly different among the tested yogurt beverage samples during storage. These results showed that yogurt beverage fortified with whey protein hydrolysates maintained antihypertensive activity and underwent no unfavorable changes in physicochemical characteristics regardless of enzyme type.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.348-348
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• 2006

In the present study, porcine pepsin in various pH conditions was investigated by small-angle X-ray scattering (SAXS) in order to detailed information on the structure and its variations with pH conditions. These analyses identified the structure of pepsin, and compared with that obtained by single crystallography. Moreover, this study found the structure' variations with changing pH conditions. All the results will be discussed with considering the conformational characteristics of pepsin in solution and further correlate to the biological and spectroscopic characteristics reported previously.

• 펄프종이기술
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• 제30권2호
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• pp.30-39
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• 1998

Effect of cationic starches and anionic colloidal silica on retention and drainage characteristics of Compozil system was investigated. Depending upon the degree of substitution and molecular weight of cationic starches and morphological characteristics of anionic colloidal silica, retention and drainage properties of Compozil system were significantly influenced. When cationic starch addition level increased above a certain limit retention and stock freeness were decreased. To elucidate this an electrostatic coagulation mechanism occurring between unadsorbed starch molecules and anionic colloidal silica was proposed. Unstructured colloidal silica showed greater improvement in retention than structured colloidal silica. Cationic corn starches with different degree of substitution and molecular weights were prepared and their effect as a constituent of Compozil system was also evaluated. By controlling the molecular weight and degree of substitution of cationic corn starch it was possible to achieve significant improvement in fines retention. Cationic corn starch with higher degree of substitution maintained its retention efficiency even when the stock conductivity was increased. Turbidity measurement technique was found to be a simple and useful method to measure the retention characteristics.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.112.3-113
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• 2003

More than 30 isolates of Alternaria were obtained from various solanaceous crops in Korea. For all isolates, morphological characteristics of the conidia were determined and compared with those of representative isolates of A. solani and A. tomatophila. Pathogenicity test was performed to Potato, tomato, egg plant and red Pepper and molecular characteristics of them including the representative isolates were determined using sequence analyses of ITS rDNA and histone H3 gene, and URP-PCR analysis. Based on morphological characteristics, the isolates from the solanaceous crops were grouped as identical or very similar to either A. tomatophila(ATO), A. solani(ASO), and unidentified Altemaria sp.(ASP). Among the molecular markers used in this study, the URP-PCR analysis was found to be appropriate for taxonomic resolution of these species. Based on the conidial morphology, pathogenicity test and molecular characteristics, A. tomatophila(early blight of tomato) could be distinguished from A. solani(early blight of potato), and the Alternaria sp.(ASP) from potato, which was closely related to A. solani in conidial morphology, was considered as a new species.

• Journal of Veterinary Science
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• 제22권5호
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• pp.69.1-69.12
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• 2021

Background: Bovine group A rotavirus (BoRVA) is a major cause of severe gastroenteritis in newborn dairy calves. Only one study has investigated the G and P genotypes among dairy calves in a few regions of China, which were G6 and P[5]. Therefore, data on the prevalence and molecular characteristics of BoRVA in dairy calves in China remains limited. Objectives: The purpose of this study was to investigate the prevalence and molecular characteristics of BoRVA in dairy calves in China. Methods: 269 dairy calves diarrheic samples from 23 farms in six provinces in China were collected to detect BoRVA using reverse transcription polymerase chain reaction. Results: 71% of samples were determined to be BoRVA-positive. Two G genotypes (G6, G10) and two P genotypes (P[1], P[5]) were identified, and G6P[1] BoRVA was the predominant strain. Moreover, the VP7 and VP4 gene sequences of these dairy calf BoRVA strains revealed abundant genetic diversity. Interestingly, eight out of 17 complete G6 VP7 sequences were clustered into G6 lineage VI and analysis showed the strains were closely related to Chinese yak BoRVA strains. Conclusions: The results of this study show that BoRVA circulates widely among dairy calves in China, and the dominant genotype in circulation is G6P[1], first report on molecular characteristics of complete P[5] VP4 genes in chinese dairy calves. These results will help us to further understand the prevalence and genetic evolution of BoRVA among dairy calves in China and, thus, prevent the disease more effectively.

• 에너지공학
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• 제18권2호
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• pp.125-131
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• 2009

경도, 내마모성과 내부식성 등과 같은 금속의 물리적 특성은 이온주입에 의해 인위적으로 제어되어 질 수 있다. 이온주입의 특성을 관찰하기 위하여 분자동역학법을 이용하여 이온과 표면원자사이의 상호작용에 대해 미시적인 원자.분자 스케일로 현상을 모델화하여 수치해석을 수행하였다. 본 연구는 이온주입의 특성을 개선하기 위한 수치해석 연구로써 미시적인 관점에서 이온주입의 프로세스를 관찰하고자 하였다. 이를 위해 주입이온속도에 따른 주입메카니즘과 초기표면온도, 이온분자량 등의 영향을 조사하였다. 그 결과 초기 표면원자층의 온도가 높은 경우에 주입에너지가 어느 값 이상이 되면 오히려 주입확률이 감소하며 또한 비결정질상태인 표면원자층에 대한 이온주입은 양호한 조건의 설정에 따라 더 효과적일 수 있음을 알 수 있었다.