• Ultrasonography
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• v.32 no.1
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• pp.59-65
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• 2013

Purpose: The purpose of this study is to establish the methodology regarding synthesis of ultrasound contrast agent imaging, and to evaluate the characteristics of the synthesized ultrasound contrast agents, including size or degradation interval and image quality. Materials and Methods: The ultrasound contrast agent, composed of liposome and SF6, was synthesized from the mixture solution of $21{\mu}mol$ DPPC (1, 2-Dihexadecanoyl-sn-glycero-3-phosphocholine, $C_{40}H_{80}NO_8P$), $9{\mu}mol$ cholesterol, $1.9{\mu}mol$ of DCP (Dihexadecylphosphate, $[CH_3(CH_2)_{15}O]_2P(O)OH$), and chloroform. After evaporation in a warm water bath and drying during a period of 12-24 hours, the contrast agent was synthesized by the sonication process by addition of buffer and SF6 gas. The size of the contrast agent was controlled by use of either extruder or sonication methods. After synthesis of contrast agents, analysis of the size distribution of the bubbles was performed using dynamic light scattering measurement methods. The degradation curve was also evaluated by changes in the number of contrast agents via light microscopy immediate, 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72 hours, and 84 hours after synthesis. For evaluation of the role as an US contrast agent, the echogenicity of the synthesized microbubble was compared with commercially available microbubbles (SonoVue, Bracco, Milan, Italy) using a clinical ultrasound machine and phantom. Results: The contrast agents were synthesized successfully using an evaporation-drying-sonication method. The majority of bubbles showed a mean size of 154.2 nanometers, and they showed marked degradation 24 hours after synthesis. ANOVA test revealed a significant difference among SonoVue, synthesized contrast agent, and saline (p < 0.001). Although no significant difference was observed between SonoVue and the synthesized contrast agent, difference in echogenicity was observed between synthesized contrast agent and saline (p < 0.01). Conclusion: We could synthesize ultrasound contrast agents using an evaporation-drying-sonication method. On the basis of these results, many prospective types of research, such as anticancer drug delivery, gene delivery, including siRNA or microRNA, targeted molecular imaging, and targeted therapy can be performed.

• Cross-Cultural Studies
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• v.48
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• pp.31-66
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• 2017

This study examines ways of recognizing and aspects of describing Korean modern literature revealed by each literary history from the viewpoint of 'transculturation', focusing on Lim Jeon-Hye's "History of Korean Literature in Japan until 1945", Shirakawa Yutaka's "Footsteps of Korean Modern Literature", and Saegusa Toshikatsu's "Taste of Korean Literature" from the history of Korean literature written in Japan. First, Lim Jeon-Hye periodically examines Korean literature written in Japan, focusing on literary activities of Korean students in Japan and the proletarian literature movement, and addresses points of active cultural negotiation, mutual understanding and political solidarity between Korea and Japan. Shirakawa Yutaka focuses on the concurrency and connection of Korea, China, and Japan in the process of modern literary formation, covering Japanese language literature and pro-Japanese literature with great care, and describes the middle-layer position as a mediating researcher in the conflicting boundaries between Korea and Japan. Saegusa Toshikatsu provides interesting transcultural momentum in exploring internal logic and denotation of Korean literature via comparative literature review encompassing East Asia, implementation of literary forms and themes connecting tradition and modernity, and an out-of-boundary point of view to overlook 'pro-Japanese literature', etc. Transcultural aspects in this literary history to examine are as follow. First, the history of Korean modern literature based on 'national literature history' is catabolized in the magnetic field of the 'colonial experience' and 'national nationalism' and considered in multifaceted context. Second, they provide the possibility of three-dimensional and micro-narrative description of literature that complement the narrative aspect of existing Korean literature history. Third, they provide an opportunity to expand and open the description of literature history through acceptance of comparative literary perspectives encompassing East Asia. Fourth, through discovery of Korean-Japanese literature and Japanese language literature, they contribute to broadening the history of Korean modern literature and enriching foundations.