• BMB Reports
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• 제37권2호
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• pp.260-267
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• 2004

Transducin (T), the heterotrimeric guanine nucleotide binding protein in rod outer segments, serves as an intermediary between the receptor protein, rhodopsin, and the effector protein, cGMP phosphodiesterase. Labeling of T with dansyl chloride (DnsCl) inhibited its light-dependent guanine nucleotide binding activity. Conversely, DnsCl had no effect on the functionality of rhodopsin. Approximately 2-3 mol of DnsCl were incorporated per mole of T. Since fluoroaluminate was capable of activating DnsCl-modified T, this lysine-specific labeling compound did not affect the guanine nucleotide-binding pocket of T. However, the labeling of T with DnsCl hindered its binding to photoexcited rhodopsin, as shown by sedimentation experiments. Additionally, rhodopsin completely protected against the DnsCl inactivation of T. These results demonstrated the existence of functional lysines on T that are located in the proximity of the interaction site with the photoreceptor protein.

• Food Science and Biotechnology
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• 제17권2호
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• pp.267-273
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• 2008

Water-soluble fraction (WSF) from edible mushroom hinmogi (Tremella fuciformis) were obtained by water extraction, and polysaccharides in the WSF were separated by ethanol precipitation. The inhibitory effects of the polysaccharides on 3T3-L1 adipocyte differentiation were evaluated by the reduction of peroxisome proliferators-activated receptor ${\gamma}$ ($PPAR{\gamma}$) translation, triglyceride accumulation, Oil Red-O staining, and expression levels of $PPAR{\gamma}$, CCAAT/enhancer binding protein a (C/$EBP{\alpha}$), and leptin. The $PPAR{\gamma}$ translation in 3T3-L1 cells was inhibited by the treatment with polysaccharide precipitated by 80% ethanol (P80) which showed highest inhibitory activity among polysaccharides tested. In addition, treatment of P80 to 3T3-L1 cells significantly inhibited the triglyceride accumulation, Oil Red-O staining, and mRNA expression of $PPAR{\gamma}$, C/$EBP{\alpha}$, and leptin in a dose-dependent manner. Based upon these results, P80 from edible mushroom hinmogi shows the inhibitory activity on the differentiation of 3T3-L1 adipocytes. Therefore, it might be employed as a potential anti-obesity material.

• 대한기계학회논문집B
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• 제22권3호
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• pp.267-279
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• 1998

A numerical study was made of flow behind a circular cylinder in a uniform flow, where the cylinder was rotationally oscillated in time. The temporal behavior of vortex formation was scrutinized over broad ranges of the two externally specified parameters, i.e., the dimensionless rotary oscillating frequency (.110.leq. $S_{f}$.leq..220) and the maximum angular amplitude of rotation (.theta.$_{max}$=15 deg., 30 deg. and 60 deg.). The Reynolds number (Re= $U_{{\inf}D}$.nu.) was fixed at Re=110. A fractional-step method was utilized to solve the Navier-Stokes equations with a generalized coordinate system. The main emphasis was placed on the initial vortex formations by varying $S_{f}$ and .theta.$_{max}$. Instantaneous streamlines and pressure distributions were displayed to show the vortex formation patterns. The vortex formation modes and relevant phase changes were characterized by measuring the lift coefficient ( $C_{L}$) and the time of negative maximum $C_{L}$( $t_{-C}$$_{Lmax}$) with variable forcing conditions.s.tions.s.s.s.

• 지구물리와물리탐사
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• 제12권3호
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• pp.263-267
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• 2009

한반도 지진자료의 총 감쇠상수($\varrho_t^{-1}$)를 고유감쇠($\varrho_i^{-1}$)와 산란감쇠($\varrho_s^{-1}$)값으로 분리된 결과를 바탕으로 다중산란 모델에 의한 이론코다감쇠($\varrho_{Cexp}^{-1}$)값을 구하고 단일산란 모델의 관측코다감쇠($\varrho_c^{-1}$)값 및 나머지 감쇠상수 값($\varrho_t^{-1}$, $\varrho_i^{-1}$,$\varrho_s^{-1}$)과 비교하였다. 그 결과, $\varrho_{Cexp}^{-1}$ 값은 $\varrho_i^{-1}$값에 근접한 모습이나, $\varrho_c^{-1}$값이 24 Hz 고주파수 대역을 제외한 대부분의 구간에서 $\varrho_i^{-1}$보다는 $\varrho_t^{-1}$에 가깝고 $\varrho_{Cexp}^{-1}$ 값과도 상이한 것으로 나타났다. 이러한 결과는 $\varrho_i^{-1}$와 $\varrho_s^{-1}$값이 실제로는 깊이에 따라 변하는 값임에도 불구하고 균일한 모델을 이용한 왜곡된 결과이다.

• Toxicological Research
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• 제26권4호
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• pp.267-273
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• 2010

As the use of carbon fullerene increases in the chemical industry, the concern over its biological and toxicological effects is also increasing. In this study, the suspension of carbon fullerene (C60) in phosphate buffered saline was prepared and toxicity was investigated using cultured RAW 264.7 and in intraperitoneally injected mice, respectively. The average size of carbon fullerene in the suspension was $53.7{\pm}26.5nm$ when determined by particle size analyzer. Cell viability was significantly decreased by the exposure of carbon fullerene ($0.25\sim2.00\;{\mu}g/ml$) for 96 hrs in the cultured RAW 264.7 cells. Intracellular reduced glutathione (GSH) level was also decreased compared to the level of the non-treated control group during the exposure period, while the level of nitric oxide was increased. When mice were intraperitoneally injected with carbon fullerene, serum cytokine levels of IL-1 and IL-6 were increased with the increased expression of inflammatory genes in peritoneal macrophage and T cell distribution in blood lymphocytes. The results suggested inflammatory responses were induced by carbon fullerene.

• Advances in nano research
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• 제13권3호
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• pp.259-267
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• 2022

Two-dimensional (2D) transition metal carbides/nitrides or "MXenes" belong to a diverse-class of layered compounds, which offer composition- and electric-field-tunable electrical and physical properties. Although the majority of the MXenes, including Ti₃C₂T_x, are metallic, they typically show semiconductor-like behaviour in their percolated thin-film structure; this is also the most common structure used for fundamental studies and prototype device development of MXene. Magnetoconductance studies of thin-film MXenes are central to understanding their electronic transport properties and charge carrier dynamics, and also to evaluate their potential for spin-tronics and magnetoelectronics. Since MXenes are produced through solution processing, it is desirable to develop deposition strategies such as inkjet-printing to enable scale-up production with intricate structures/networks. Here, we systematically investigate the extrinsic negative magnetoconductance of inkjetprinted Ti₃C₂T_x MXene thin-films and report a crossover from weak anti-localization (WAL) to weak localization (WL) near 2.5K. The crossover from WAL to WL is consistent with strong, extrinsic, spin-orbit coupling, a key property for active control of spin currents in spin-orbitronic devices. From WAL/WL magnetoconductance analysis, we estimate that the printed MXene thin-film has a spin orbit coupling field of up to 0.84 T at 1.9 K. Our results and analyses offer a deeper understanding into microscopic charge carrier transport in Ti₃C₂T_x, revealing promising properties for printed, flexible, electronic and spinorbitronic device applications.

• ALGAE
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• 제17권3호
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• pp.195-199
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• 2002

We investigated the association of Chlorella vulgaris and E. coli W9110 in removal of total organic carbon with the lab-scaled continuous river water flow system (CRWFS). Artificial wastewater was applied at two levels of organic carbon concentration; 1,335 $mg{\cdot}l^{-1}$ in the treatment (T)-1 and 267 $mg{\cdot}l^{-1}$ in T-2. The highest densities of C. vulgaris were $8.3{\times10^6\;cells{\cdot}ml^{-1}$ in T-1 and $6.9{\times}10^6\;cells{\cdot}ml^{-1}$ in T-2. The maximum densities of E. coli W3110 were $2.0{\times}10^8$ clony forming unit (CFU)${\cdot}ml^{-1}$ in T-1 and $3.9{\times}10^8\;CFU{\cdot}ml^{-1}$ in T-2. The densities increased during the first 11 days in T-q and 4 days in T-2, and decreased rapidly till 35th day, then increased slightly afterwards. This trend was prominent in T-2. It was inplied that wider range of nutrients was required in the growth of heterotrophic bacteria in T-2 than in T-1. The algal biomass should be increased effectively for the successful removal of organic carbon.

• 한국버섯학회지
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• 제16권4호
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• pp.267-271
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• 2018

봉지재배용 표고의 적합한 배지를 개발하고자 본 연구를 수행한 결과 참나무톱밥+미송톱밥+미강(40:40:20, v/v) 혼합배지인 T5에서 pH 5.3으로 대조구와 비슷하였으며 C/N율은 71.8로 대조구 85.2 대비 낮은 경향이었다. 배양특성은 T5에서 대조구 대비 산조701호는 13일, 농진고는 18일 배양기간이 단축되었다. 자실체 특성조사 결과 산조701호 품종에서는 T5에서 대조구 대비 갓이 크고 두꺼웠으며, 대도 길고 두꺼워 개체중이 높게 나타났다. 반면 농진고 품종에서는 대조구와 비슷한 경향이었다. 배지조성에 따른 혼합배지별 수량은 T5에서 대조구 대비 산조701호는 17%, 농진고는 19% 증수되었다. 이러한 연구 결과를 바탕으로 참나무톱밥의 50%를 미송톱밥으로 대체할 경우 배양기간이 단축되고 수량이 증수되며 또한 생산비 절감이 가능할 것이라 판단되었다.

• Current Research on Agriculture and Life Sciences
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• 제31권1호
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• pp.18-24
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• 2013

This work attempted to fabricate organic/inorganic nanocomposite by combining organic cellulose nanofibrils (CNFs), isolated by 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO)-mediated oxidation of native cellulose with inorganic nanoclay. The morphology and dimension of CNFs, and tensile properties and thermal stability of CNF/clay nanocomposites were characterized by transmission electron microscope (TEM), tensile test, and thermogravimetry (TG), respectively. TEM observation showed that CNFs were fibrillated structure with a diameter of about $4.86{\pm}1.341nm$. Tensile strength and modulus of the hybrid nanocomposite decreased as the clay content of the nanocomposite increased, indicating a poor dispersion of CNFs or inefficient stress transfer between the CNFs and clay. The elongation at break increased at 1% clay level and then continuously decreased as the clay content increased, suggesting increased brittleness. Analysis of TG and derivative thermogravimetry (DTG) curves of the nanocomposites identified two thermal degradation peak temperatures ($T_{p1}$ and $T_{p2}$), which suggested thermal decomposition of the nanocomposites to be a two steps-process. We think that $T_{p1}$ values from $219.6^{\circ}C$ to $235^{\circ}C$ resulted from the sodium carboxylate groups in the CNFs, and that $T_{p2}$ values from $267^{\circ}C$ to $273.5^{\circ}C$ were mainly responsible for the thermal decomposition of crystalline cellulose in the nanocomposite. An increase in the clay level of the CNF/clay nanocomposite predominately affected $T_{p2}$ values, which continuously increased as the clay content increased. These results indicate that the addition of clay improved thermal stability of the CNF/clay nanocomposite but at the expense of nanocomposite's tensile properties.

• Journal of Animal Science and Technology
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• 제45권5호
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• pp.679-688
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• 2003

본 연구는 재래돼지와 랜드레이스를 기초축으로 한 F$_2$ 354두에 대해 Leptin receptor와 연관되어있는 초위성체 표지인자를 이용하여 그 다형성을 조사하고 돼지의 성장형질, 도체형질, 육질형질과 그 유전자형간의 연관성을 구명코자 실시하였다. F$_2$ 354두로부터 얻어진 총 대립유전자는 255bp, 259bp 261bp, 263bp, 265bp, 267bp로써 총 6가지 형태로 나타났다. 집단 내에서 6개의 대립유전자들은 19가지의 유전자형 조합을 나타내었고 가장 많이 나타난 유전자형은 CE형 (261bp/265bp)으로 전체의 20.0%를 차지하였고 다음으로 CC(261/261)와 EE(265/ 265)가 각각 10.1%와 9.6%로 나타났으며 AC(255/261)와 EF(265/267)은 각각 1두에서만 관찰되었다. 각 유전자형간 12주령 체중이 고도의 유의성을 가지고 있었고 (P〈0.001), 3주령 체중(P〈0.05)과 30주령 체중(P〈0.01)에서도 유의성을 보였다. 특히, 성장초기와 달리 12주령 이후 돼지의 증체율은 급증하게 되고 각 개체간의 증체량에 대한 변이가 커지게 되는 것으로 나타났다. 3, 5, 12, 30주령 체중에서 DD(263/263), DF(263/267)형은 항상 상위를 나타내는 유전자형들로 나타났다. 특히 263bp 대립유전자를 가지고 있는 유전자형에 있어서 증체량에 대한 영향력이 크게 나타났다. 각 유전자형간 도체지방과 전단력도 유의성을 가지고 있었고 (P〈0.001), 등지방층 두께에서도 유의성을 보였다(P〈0.05). 그러나 근내지방함량에 대해서는 LEPR 유전자형들의 영향을 미치지 못하는 것으로 나타났다. 등지방층 두께와 도체지방에 대한 최상위 값을 갖는 유전자형은 두 형질 모두 DF (263/267)형으로 나타났다. 반면, 등지방층 두께에서 최하위 값을 갖는 유전자형은 AB (255/259), BE (259/265), AE(255/265) 순으로 나타났고, 도체지방에서는 AB(255/259), DD (263/263), AE(255/ 265) 순으로 나타났다. 특히 255, 259, 265bp 대립유전자를 갖는 개체들은 두 형질에 있어서 부의 상관관계를 갖는 것으로 판단되어진다. 전단력의 평균값이 각각 4.59kg/$cm^3$과 4.52kg/$cm^3$인 DD(263/263), BB(259/259)가 등심근육의 연도를 저하시켰고 반대로 DF(263/267) 유전자형을 갖은 개체는 더 좋은 연도를 나타내었다.