• Journal of Nutrition and Health
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• 제48권5호
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• pp.451-456
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• 2015

Purpose: Neuronal apoptotic events induced by aging and hypoxic/ischemic conditions is an important risk factor in neurodegenerative diseases such as ischemia stroke and Alzheimer's disease. The peel of Citrus sunki Hort. ex Tanaka has long been used as a traditional medicine, based on multiple biological activities including anti-oxidant, anti-inflammation, and anti-obesity. In the current study, we examined the actions of fermented C. sunki peel extract against cobalt chloride ($CoCl_2$)-mediated hypoxic death in human neuroblastoma SH-SY5Y cells. Methods: Cell viability was measured by trypan blue exclusion. Expression of apoptosis related proteins and release of cytochrome c were detected by western blot. Production of intracellular reactive oxygen species (ROS) and apoptotic morphology were examined using 2',7'-dichlorofluorescin diacetate (DCF-DA) and 4',6-diamidino-2-phenylindole (DAPI) staining. Results: Exposure to $CoCl_2$, a well-known mimetic agent of hypoxic/ischemic condition, resulted in neuronal cell death via caspase-3 dependent pathway. Extract of fermented C. sunki peel significantly rescued the $CoCl_2$-induced neuronal toxicity with the cell viability and appearance of apoptotic morphology. Cytoprotection with fermented C. sunki peel extract was associated with a decrease in activities of caspase-3 and cleavage of poly (ADP ribose) polymerase (PARP). In addition, increase in the intracellular ROS and release of cytochrome c from mitochondria to the cytosol were inhibited by treatment with extract of fermented C. sunki peel. Conclusion: Based on these data, fermented C. sunki peel extract might have a protective effect against $CoCl_2$-induced neuronal injury partly through generation of ROS and effectors involved in mitochondrial mediated apoptosis.

• BMB Reports
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• 제43권5호
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• pp.362-368
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• 2010

Dermcidin is a human antibiotic peptide that is secreted by the sweat glands and has no homology to other known antimicrobial peptides. As an initial step toward understanding dermcidin's mode of action at bacterial membranes, we used homonuclear and heteronuclear NMR to determine the conformation of the peptide in 50% trifluoroethanol solution. We found that dermcidin adopts a flexible amphipathic $\alpha$-helical structure with a helix-hinge-helix motif, which is a common molecular fold among antimicrobial peptides. Spin-down assays of dermcidin and several related peptides revealed that the affinity with which dermcidin binds to bacterial-mimetic membranes is primarily dependent on its amphipathic $\alpha$-helical structure and its length (>30 residues); its negative net charge and acidic pI have little effect on binding. These findings suggest that the mode of action of dermcidin is similar to that of other membrane-targeting antimicrobial peptides, though the details of its antimicrobial action remain to be determined.

• 공업화학
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• 제9권7호
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• pp.1090-1097
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• 1998

국부 마취제로 이용되는 lidocaine 화합물들이 마취 효과를 나타내는 과정을 알아보기 위하여 세포벽을 구성하는 지질 이중막의 모사 시스템으로 공기/물 계면에 형성된 지질 단분자 막을 이용하여 lidocaine 화합물들이 지질 단분자 막의 팽창에 미치는 영향을 연구하였다. Lidocaine이 신경 세포와 접하게 되면 세포벽을 구성하는 지질 이중막을 팽창시켜 이중막에 함침된 단백질을 압축하여 이를 통한 이온 통과가 차단되어 신경 전달이 마비된다는 가설과, 단백질 이온 통로에 존재하는 lidocaine receptor에 직접 흡착되어 이온 통로를 막는다는 가설이 구체적 실험 없이 제안되었다. 본 연구에서는 두 가설 타당성을 증명하고자 리피드 단분자 막팽창에 lidocaine이 미치는 영향을 조사하였다. 실험 결과 유용성인 lidocaine은 phosphatidyl choline, sphingomyelin, DS-PL95E, lipoid의 단분자 막을 수축시켰으며 phosphatidyl ethanolamine은 특정 조성 범위에서만 단분자 막을 팽창시켰다. 반면 수용성인 lidocaine-HCl 염은 실험에 사용된 모든 지질의 단분자 막을 팽창시켰다.

• 제어로봇시스템학회논문지
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• 제13권4호
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• pp.279-285
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• 2007

The objective of the research is two fold. The first is to design and propose a stable and robust learning control algorithm. The controller is CMAC Learning Controller which consists of a model-based controller, such as LQR or PID, as a reference control and a CMAC. The second objective is to implement a reference control and CMAC at two different sampling rates. Generally, a conventional controller is designed based on a mathematical plant model. However, increasing complexity of the plant and accuracy requirement on mathematical models nearly prohibits the application of the conventional controller design approach. To avoid inherent complexity and unavoidable uncertainty in modeling, biology mimetic methods have been developed. One of such attempts is Cerebellar Model Articulation Computer(CMAC) developed by Albus. CMAC has two main disadvantages. The first disadvantage of CMAC is increasing memory requirement with increasing number of input variables and with increasing accuracy demand. The memory needs can be solved with cheap memories due to recent development of new memory technology. The second disadvantage is a demand for processing powers which could be an obstacle especially when CMAC should be implemented in real-time. To overcome the disadvantages of CMAC, we propose CMAC learning controller with multiple sampling rates. With this approach a conventional controller which is a reference to CMAC at high enough sampling rate but CMAC runs at the processor's unoccupied time. To show efficiency of the proposed method, an inverted pendulum controller is designed and implemented. We also demonstrate it's possibility as an industrial control solution and robustness against a modeling uncertainty.

• 건축역사연구
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• 제9권2호
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• pp.85-100
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• 2000

This paper is a study of the Beaux-Arts discipline of architecture, as it was established during the late nineteenth century in America. It focuses on trio particular modes of vision and representation that were at the heart of the discipline. The paper argues that Beaux Arts vision was centered on what may be called 'planar vision'; a mode of seeing through which the multiple aspects of the architectural design imbedded in the plan were read and re-interpreted. Similarly Beaux-Arts training in drawing required its student to draw within the multiple layers of historical traces; the new design being in effect a new layer placed on often unseen traces of monumental precedent. The theoretical basis of this practice was not based on history but on the concept of composition. Composition, in the French tradition was regarded more a matter of practice than theory. The Anglo-American discourse on composition, on the other hand, formed a body of theoretical literature based on formalist assumptions. There was, however, a fundamental gap between these formalist theories of composition and the 'layered' modes of vision and drawing involved in the design process. This practice leaned more on the modern romantic notion of 'intuition' for its theoretical basis, once again forming an immanent conflict with the mimetic practice of classical and historical architecture. The paper draws a picture of a discipline centered on a 'theory of the plan,' a potentially modern discipline integrated with classical forms and details. It was clearly effective as a practice. However, structured by conflicts between theory and practice, history and form, mimesis and intuition, the Beaux-Arts was unable to defend itself at the philosophical and theoretical level the modernists engaged their attacks on this system. At the same time, the paper poses the question of how different modern architecture is from this system. Is not the 'theory of plan,' in its many transformations and guises, still the central discipline of twentieth century modern architecture, and is it not structured by basically the same kind of conflicts and paradox that were immanent to the Beaux-Arts system.

• BMB Reports
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• 제45권1호
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• pp.32-37
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• 2012

Alternative splicing generates several interleukin-6 (IL-6) isoforms; for them an antagonistic activity to the wild-type IL-6 has been proposed. In this study we quantified the relative abundance of IL-6 mRNA isoforms in a panel of mouse tissues and in C2C12 cells during myoblast differentiation or after treatment with the $Ca^{2+}$ ionophore A23187, the AMP-mimetic AICAR and TNF-${\alpha}$. The two mouse IL-6 isoforms identified, IL-6${\delta}$5 (deletion of the first 58 bp of exon 5) and IL-6${\delta}$3 (lacking exon 3), were not conserved in rat and human, did not exhibit tissue specific regulation, were expressed at low levels and their abundance closely correlated to that of full-length IL-6. Species-specific features of the IL-6 sequence, such as the presence of competitive 3' acceptor site in exon 5 and insertion of retrotransposable elements in intron 3, could explain the production of IL-6${\delta}$5 and IL-6${\delta}$3. Our results argued against biological significance for mouse IL-6 isoforms.

• 아동학회지
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• 제34권2호
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• pp.1-25
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• 2013

The purpose of this study was to examine the relationship among infants' nonverbal communication, maternal verbal behaviors and the infants' acquisition of vocabulary. The subjects were 93 pairs of 10 to 18 months old infants and their mothers residing in the Seoul and GyeongGi-Do area. The results were as follows : (1) In terms of the infants' nonverbal communicative means, it appeared that the group of 16~18 month olds utilized more gesture and vocalization. As regards the infants' nonverbal communicative functions in terms of social behavior and joint attention, the group of 16~18 month olds was found to perform more of the behaviors from this category than the other groups. There was a significant difference in the maternal verbal behavior among the different age groups. (2) Among the infants' nonverbal communicative means, gesture and vocalization, there appeared to be a significant relationship between vocalization and the infants' acquisition of vocabulary. In addition, there was an important relationship between the high usage of infants' nonverbal communicative functions with behavior regulation and the high usage of joint attention and the successful acquisition of vocabulary among infants. (3) Social play, which is a maternal verbal behavior categorized as one of the strategies for getting infants' attention, was significantly related to the acquisition of infants' vocabulary. (4) When mothers used more imitating sounds and mimetic words, requests for information, descriptions, conventional social expressions, and imitation to enhance responsiveness, infants were found to have acquired a larger vocabulary.

• BMB Reports
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• 제36권6호
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• pp.552-557
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• 2003

Oligomers with $\alpha$-aminooxy acids are reported to form very stable turn and helix structures, and they are supposed to be useful peptidomimetics for drug design. A recent report suggested that homochiral oxa-peptides form a strong eight-member-ring structure by a hydrogen bond between adjacent aminooxy-acid residues in a $CDCl_3$ solution. In order to design an $\alpha$-MSH analog with a stable turn conformation, we synthesized four tetramers and one pentamer, based on $\alpha$-MSH sequence, and determined the solution structures of the molecules by two-dimensional NMR spectroscopy and simulated annealing calculations. The solution conformations of the three peptidomimetic molecules (TLV, TDV, and TLL) in DMSO-$d_6$ contain a stable 7-membered-ring structure that is similar to a $\gamma$-turn in normal peptides. Newly-designed tetramer TDF and pentamer PDF have a ball-type rigid structure that is induced by strong hydrogen bonds between adjacent amide protons and carbonyl oxygens. In conclusion, the aminooxy acids, easily prepared from natural or unnatural amino acids, can be employed to prepare peptidomimetic analogues with well-defined turn structures for pharmaceutical interest.

• 한국콘텐츠학회논문지
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• 제13권2호
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• pp.412-419
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• 2013

차별화가 경쟁우위의 필수적인 요건으로 인식되고 있음에도 불구하고 기업이 운영하고 있는 인사제도의 측면에서 본다면 오히려 그 반대의 모습을 발견할 수 있다. 각 기업은 차이점으로 구분되기 보다는 동질적인 측면을 보다 많이 찾아볼 수 있다. 본 연구는 선행연구에서 제시된 개별 기업간 인사제도의 유사성에 대한 논의를 이론적인 차원에서 보다 면밀히 구조화하고자 하였다. 본 연구는 이론적 차원에서 동형화와 관련된 기존 논의를 구체적으로 제시하고, 이를 토대로 각 기업의 인사제도 도입에 따른 동학적 특성을 탐색적인 차원에서 분석하여 인적자원관리의 현실적인 시사점을 찾아보는 것을 목적으로 하였다. 본 연구는 선행연구에서 제시된 개별 기업간 인사제도의 유사성에 대한 논의를 탐색적 차원에서 보다 체계적으로 논의하였다. 또한 신제도주의적 관점에서 동형화와 관련된 기존 논의를 제시하고, 이를 토대로 각 기업의 서로 유사한 인사제도 도입에 따른 동학적 특성을 기존 연구를 바탕으로 분석하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.5.1-5.1
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• 2010

One of the most important environmental problems is global warming. Global warming is caused by increase in the amounts of water vapor, methane, carbon dioxide and other gases being released into the atmosphere as a result of the burning of fossil fuels. It has thus become important to reduce fossil fuel use. Environmentally friendly preparation of functional materials has, therefore, attracted much interest for environmental problems. Furthermore, nature mimetic processes are recently been of great interest as environmentally friendly one. There have been many studies on fabrication of various functional nanocrystals. Among various nanocrystal fabrication techniques, flux growth is an environmentally friendly, very convenient process and can produce functional nanocrystals at temperatures below the melting points of the solutes. Furthermore, this technique is suitable for the synthesis of crystals having an enhedral habit. In flux growth, the constituents of the materials to be crystallized are dissolved in a suitable flux (solvent) and crystal growth occurs as the solution becomes critically supersaturated. The supersaturation is attained by cooling the solution, by evaporation of the solvent or by a transport process in which the solute is made to flow from a hotter to a cooler region. Many kinds of oxide nanocrystals have been grown in our laboratory. For example, zero- (e.g., particle), one- (e.g., whisker and tube) and two-dimensional (e.g., sheet) nanocrystals were successfully grown by flux method. Our flux-growth technique has some industrial and ecological merits because the nanocrystal fabrication temperatures are far below their melting points and because the used reagents are less harmless to human being and the environment.