• Journal of Microbiology and Biotechnology
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• 제29권2호
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• pp.235-243
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• 2019

A special eosinophilic agarase exo-type ${\beta}$-agarase gene, AgaDL6, was cloned from a marine agar-degrading bacterium, Flammeovirga sp. HQM9. The gene comprised 1,383-bp nucleotides encoding a putative agarase AgaDL6 of 461 amino acids with a calculated molecular mass of 52.8 kDa. Sequence analysis revealed a ${\beta}$-agarase domain that belongs to the glycoside hydrolase family (GH) 16 and a carbohydrate-binding module (CBM_4_9) unique to agarases. AgaDL6 was heterologously expressed in Escherichia coli BL21 (DE3). Enzyme activity analysis of the purified protein showed that the optimal temperature and pH of AgaDL6 were $50^{\circ}C$ and 3.0, respectively. AgaDL6 showed thermal stability by retaining more than 98% of activity after incubation for 2 h at $50^{\circ}C$, a feature quite different from other agarases. AgaDL6 also exhibited outstanding acid stability, retaining 100% of activity after incubation for 24 h at pH 2.0 to 5.0, a property distinct from other agarases. This is the first agarase characterized to have such high acid stability. In addition, we observed no obvious stimulation or inhibition of AgaDL6 in the presence of various metal ions and denaturants. AgaDL6 is an exo-type ${\beta}$-1,4 agarase that cleaved agarose into neoagarotetraose and neoagarohexaose as the final products. These characteristics make AgaDL6 a potentially valuable enzyme in the cosmetic, food, and pharmaceutical industries.

• Natural Product Sciences
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• 제17권1호
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• pp.5-9
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• 2011

An alkaloid, 3-methylcanthin-5, 6-dione, was isolated from the stem of Picrasma quassioides (D. Don) Benn. and characterized by comprehensive analyses of its 1D and 2D NMR spectra. It was also evaluated for its cytotoxic activity in vitro against three human cancer cell lines (MDA-MB-231, HT-29 and NCI-N87), using MTT assays. We found that 3-methylcanthin-5, 6-dione exhibited significant anti-inflammatory activity via inhibiting NO production induced in LPS-stimulated murine macrophage RAW264.7 cells. The antioxidant activity of 3-methylcanthin-5, 6-dione was measured by DPPH free radical scavenging assays, hydroxyl radical scavenging assays and reducing power assays. Our results showed that 3-methylcanthin-5, 6-dione has significant biological activities.

• 환경위생공학
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• 제13권2호
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• pp.40-46
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• 1998

For a biological control on a plant pathogen, Pryicularia Oryzae, and a mosquito, Aedes aegypti, Bacillus thuringiensis strain AF6 which produces parasporal inclusion, delta-endotoxin, was isolated. The B. thuringiensis strain AF6 was produced not only an antifungal substance(AFS) against P. oryzae, but also a mosquitocidal delta-endotoxin. The AFS of the strain AF6 in more stable at pH 4.0 than pH 10.0. At the mode of action, the AFS of the strain AF6 was inhibited hypha growth on potato agar plate(pH 5.0), and degraded cell walls of P. oryzae.

• Geomechanics and Engineering
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• 제7권6호
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• pp.633-647
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• 2014

Biopolymers, polymers produced by living organisms, are used in various fields (e.g., medical, food, cosmetic, medicine) due to their beneficial properties. Recently, biopolymers have been used for control of soil erosion, stabilization of aggregate, and to enhance drilling. However, the inter-particle behavior of such polymers on soil behavior are poorly understood. In this study, an artificial biopolymer (${\beta}$-1,3/1,6-glucan) was used as an engineered soil additive for Korean residual soil (i.e., hwangtoh). The geotechnical behavior of the Korean residual soil, after treatment with ${\beta}$-1,3/1,6-glucan, were measured through a series of laboratory approaches and then analyzed. As the biopolymer content in soil increased, so did its compactibility, Atterberg limits, plasticity index, swelling index, and shear modulus. However, the treatment had no effect on the compressional stiffness of the residual soil, and the polymer induced bio-clogging of the soil's pore spaces while resulting in a decrease in hydraulic conductivity.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2010년도 춘계학술대회
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• pp.55-61
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• 2010

Many enterprises are looking for counterproposals to be survival through innovation activities and to be held on their continuous businesses for their business management environments nowadays. One of the innovation activities is an improvement of Loss and reinforcement of business structure through Lean, TPM. Another one is an improvement of these innovation activities and have achieved lots of outcomes (profits). But most these activities have been applied for only the industries in Automobile, Semiconductor, Aviation, Construction with large enter in Korea. And most of minor cable enterprises don't even try to import these innovation activities excluding some how the small and medium cable enterprise can import the LEAN / 6 Sigma activities effectively with some of sample in real small and medium cable company.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
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• pp.625-627
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• 2005

본 논문은 인텔사의 IXP2400 네트워크 프로세서를 이용하여 IPv6 multicast-enabled 라우터 개발의 예비단계로서 IPv6 멀티캐스트 모듈의 전체적인 설계 및 구현을 다룬다. 특히, 마이크로 엔진할당, IPv6 멀티캐스트 마이크로 블록 및 패킷 복사 마이크로 블록에 중점을 둔다. 우리의 IPv6 멀티캐스트 포워딩 모듈의 성능측정 결과는 이론적 한계치의 $86\%$였다.

• 수산경영론집
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• 제41권2호
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• pp.45-60
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• 2010

The objective of this article was to estimate the market size of recreational fishing in Korea. Data were collected through sample surveys of 3,081 households nationwide in 2008. The number of anglers was directly estimated by applying weights expressed as the ratio of population to the sample. Yields and expenditures were estimated based on modules developed. On the basis of the results, a total of 6,524 thousand anglers caught an estimated 643,343 thousand fish, divided 65.2% on inland lake and 34.8% on saltwater. An angler caught about 98 fish on average in 2008. A typical angler went fishing 9.6 times, divided 8.4 times on inland lake and 5.5 times on sea. An annual expenditure of 5,233.6 billion won was estimated. The total was divided 2,851.4 billion won on inland lake(54.5%) and 2,382.2billion won on saltwater(45.5%). An average angler spent 802 thousand won a year. This study also estimated volumes by various types of fish.

• 대한수학회논문집
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• 제35권2호
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• pp.401-415
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• 2020

It is well-known that if char𝕜 = 0, then an Artinian monomial complete intersection quotient 𝕜[x₁, …, x_n]/(x₁^a₁, …, x_n^a_n) has the strong Lefschetz property in the narrow sense, and it is decomposed by the direct sum of irreducible 𝖘𝖑₂-modules. For an Artinian ring A = 𝕜[x₁, x₂, x₃]/(x₁⁶, x₂⁶, x₃⁶), by the Schur-Weyl duality theorem, there exist 56 trivial representations, 70 standard representations, and 20 sign representations inside A. In this paper we find an explicit basis for A, which is compatible with the S₃-module structure.

• Journal of Chest Surgery
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• 제48권6호
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• pp.411-414
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• 2015

Interrupted aortic arch with an aortopulmonary window is a rare congenital entity that is associated with high morbidity and mortality, especially in premature low-birth-weight infants, and the proper timing of surgical correction remains a matter of debate. We present the case of a premature infant weighing 1.6 kg who successfully underwent one stage surgical repair to treat interrupted aortic arch with an aortopulmonary window. The therapeutic management of this patient is described below, and a review of the literature is presented.

• Structural Engineering and Mechanics
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• 제5권1호
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• pp.69-83
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• 1997

A new efficient hybrid/mixed thin~moderately thick plate bending element with 6-node (HM6-14) is formulated based on the Reissner-Mindlin plate bending theory. The convergence of this element is proved by error estimate theories and verified by patch test respectively. Numerical studies on such an element as HM6-14 demonstrate that it has remarkable convergence, invariability to geometric distorted mesh situations, to axial rotations, and to node positions, and no "locking" phenomenon in thin plate limit. The present element is suitable to many kinds of shape and thin~moderately thick plate bending problems. Further, in comparison with original hybrid/mixed plate bending element HP4, the present element yields an improvement of solutions. Therefore, it is an efficient element and suitable for the development of adaptive multi-field finite element method (FEM).