From 1990, Seoul Metropolitan Government has established an urban master plan for the efficient city management by introducing the central place structure with a multi-tiered hierarchy. In the plan, Seoul City uses the strategy of developing the station influence area around the urban railway, in order to form the central place structure, effectively. . Therefore, reviewing impacts of urban railway is the most fundamental study for understanding changes in the spatial structures of Seoul. In the study, we have analyzed the changes in the central place structure of Seoul City with the public land price changes in station influence area around the urban railway at each year of 2000, 2005, and 2010. As a result, we could easily recognize the changes in the hierarchical central place structure by analyzing the time-series changes of public land price in station influence area. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Keywords

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Baekjung' adaptable to high temperature was made by crossing between monokaryon derived from selfing of brown strain and monokaryon derived from Korea white strain. In the condition that temperature is maintained at 10 o C without low temperature of 4 o

Herein we present a diagnostic paper chip that can quantitatively detect albumin without external electronic reader and dispensing apparatus. We fabricated a diagnostic paper chip device by printing wax barrier on the paper and wicking it with citrate buffer and tetrabromophenol blue to detect albumin in sample solution. The paper chip is so simple that we dropped a sample solution at sample pad and measure the ratio of two travel distances of the sample solvent and albumin under the name of retention factor. Our result confirmed that the retention factor was constant in the samples with same concentration of albumin and useful determinant for the measurement of albumin concentration. The paper chip is affordable and equipment-free, and close to ideal point-of-care test in accordance with the assured criteria, outlined by the World Health Organization. We assume that this diagnostic paper chip will expand the concept of colorimetric determination and provide a inexpensive diagnostic method to aging society and developing country.

1) Emulsions are mixture of immiscible liquids in which one is dispersed in all over the other. They have been applied to many applications including cosmetics, foods, drug delivery system (DDS), fine chemicals, and chemical separations. Especially, emulsion technology is one of the most useful technique to formulate cosmetics such as eye cream, foundation, and foam cleansing. In general, the emulsions can be generated by mechanical agitation of two immiscible fluids. However, the emulsions obtained by conventional method have limited in stability, monodispersity, and complicate process. We describe here preparation techniques of representative cosmetic emulsions such as liposome, liquid crystal emulsion, nanoemulsion, multiple emulsion, and pickering emulsion. Furthermore, various factors which can control the physical properties of each cosmetic emulsions are briefly discussed.

유체로는 "spreading coefficient"를 도입 하여 시스템 내에서 이중 에멀젼을 형성하는 조건을 예측하여 물과 0.5% w/w sodium dodecyl sulfate 혼합물, 헥사 데칸 혼합물(hexadecane; 1% w/w Span80)을 선정하였다. 이를 통하여, 코어 및 쉘의 사이즈가 48.5 µm(CV:1.6%), 65.1 µm(CV:1.6%)인 단분산성 이중 에멀젼을 성공적으로 생성하였고, 유체의 유량 제어를 통하여 함입되는 코어 의 개수 조절이 가능함을 보여주었다.Abstract: This study presents the preparation of double emulsions in a poly(dimethylsiloxane) (PDMS)-based microfluidic device. To improve the wettability of hydrophilic continuous phase onto a hydrophobic PDMS microchannel, the surface was modified with 3-(trimethoxysilyl) propyl methacrylate (TPM) and then sequentially reacted with acrylic acid monomer solution, which produced selective covalent bonding between acrylic acids and methacrylate groups. For the proof of selective surface modification, tolonium chloride solution was used to identify the modified region and we confirmed that the approach was successfully performed. When water containing 0.5% w/ w sodium dodecyl sulfate and 1% w/w Span80 with hexadecane were loaded into the selectively modified microfluidic channels, we can produce stable double emulsion. Based on the spreading coefficients, we predict the morphology of double emulsions. Our proposed method efficiently produces monodisperse double emulsions having 48.5 µm (CV:1.6%) core and 65.1 µm (CV:1.6%) shell. Furthermore, the multiple emulsions having different numbers of core were easily prepared by simple control of flow rates.

We present microfluidic method to rapidly analyze the effect of temperature on the change of morphologies of Antarctic bacteria (Pseudoalteromonas sp., Shewanella vesiculosa, Shewanella sp., and Cellulophaga sp.). The microfluidic device is able to generate stable temperature gradient from 7 to 40 o C and dramatically reduce the number of experiments, experimental cost and labor, and amount of sample. Based on this approach, we found that specific bacteria transforming morphology into filament or elongated body strongly depends on cultivation temperature. Interestingly, we found that the morphologies of Pseudoalteromonas sp., Shewanella vesiculosa, Shewanella sp., and Cellulophaga sp. are elongated at below 25 o C, above 20 o C, above 15 o C and above 35 o C, respectively. We envision the microfluidic device is a useful approach to analyze biological events with a high throughput manner.

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