The effects of nano addition to superconducting properties of processed superconductors was examined. 0.1 wt.% and 1 wt.% nano powders were mixed with boron and magnesium powders by ball milling. The powder mixtures were made into pellets by uniaxial pressing. The pellets were heat-treated at in argon atmosphere for formation. It was found by powder X-ray diffraction that the raw powders were completely converted into after the heat treatment. The superconducting transition temperature () and critical current density (), estimated from susceptibility-temperature and curves, were decreased by nano addition. The and decrease by nano addition are attributed to the incorporation of iron and carbon with lattices (Fe substitution for Mg and C substitution for B) due to the high reactivity of the nano powder.

본 연구는 기존 철근콘크리트 구조물에 대하여 대표적인 변위-기반 설계법인 Chopra&Goel 이 제안한 직접변위-기반 설계법의 기본개념을 적용하여 최대 설계지반 가속도에 대한 보강 Steel Jacket의 두께를 결장하고, 결정된 보강 두께를 적용하여 보강전 후 성능설계기법에 의한 비선형 해석 및 보강설계법에 의한 보다 개선된 알고리즘 및 프로그램을 제시하였다. Steel Jacket 보강된 철근콘크리트 기둥에 대한 설계 변위 추정을 위해 Steel Jacket 보강된 철근콘크리트 부재의 비선형 층상화 세그멘트 해석 모델을 제시하고, 성능기반설계에 의한 성능개선설계를 위하여 목표성능변위 및 설계자전가속도 조건에 대해 직접 변위-기반 설계 방법 및 변위계 수법에 의한 내진성능개선 설계 방법을 제시하였다. 적용 예에서 본 방법은 기존 철근콘크리트 기둥과 비교하여 성능개선설계 결과 보강 전에 비해 변위 연성비 및 변위성능에서 크게 개선된 성능설계 결과를 제공해 주었다.

Pluripotency of human embryonic stem cell (hESC) is one of the most valuable ability of hESCs for applying cell therapy field, but also showing side effect, for example teratoma formation. When transplant multipotent stem cell, such as mesnchymal stem cell (MSC) which retains similar differentiation ability, they do not form teratoma in vivo, but there exist limitation of cellular source supply. Accordingly, differentiation of hESC into MSC will be promising cellular source with strong points of both hESC and MSC line. In this study, we described the derivation of MSC like cell population from feeder free cultured hESC (hESC- MSC) using direct differentiation system. Cells population, hESC-MSC and bone marrow derived MSC (BM-MSC) retained similar characteristics in vitro, such as morphology, MSC specific marker expression and differentiation capacity. At the point of differentiation of both cell populations, differentiation rate was slower in hESC-MSC than BM-MSC. As these reason, to verify differentially expressed molecular condition of both cell population which bring out different differentiation rate, we compare the molecular condition of hESC-MSC and BM-MSC using 2-D proteomic analysis tool. In the proteomic analysis, we identified 49 differentially expressed proteins in hESC-MSC and BM-MSC, and they involved in different biological process such as positive regulation of molecular function, biological process, cellular metabolic process, nitrogen compound metabolic process, macromolecule metabolic process, metabolic process, molecular function, and positive regulation of molecular function and regulation of ubiquitin protein ligase activity during mitotic cell cycle, cellular response to stress, and RNA localization. As the related function of differentially expressed proteins, we sought to these proteins were key regulators which contribute to their differentiation rate, developmental process and cell proliferation. Our results suggest that the expressions of these proteins between the hESC-MSC and BM-MSC, could give to us further evidence for hESC differentiation into the mesenchymal stem cell is associated with a differentiation factor. As the initial step to understand fundamental difference of hESC-MSC and BM-MSC, we sought to investigate different protein expression profile. And the grafting of hESC differentiation into MSC and their comparative proteomic analysis will be positively contribute to cell therapy without cellular source limitation, also with exact background of their molecular condition.

Embryoid bodies (EBs) generated from human embryonic stem cells (hESCs) include spontaneously induced endodermal lineage cells (ELCs). Activin-A plays important roles in the endoderm differentiation of hESCs. Despite studies on the generation of ELCs from hESCs with treatment of Actvin-A, it was unclear for localization and pattern of ELCs by Activin-A during differentiation of hESCs. Accordingly in this study, we knew that Actvin-A increased the cystic EBs formation, including the highly enriched AFP (endoderm lineage specific marker)-expressing cells in the surface of cystic EBs. To induce the EBs formation from undifferentiated hESCs, cells were transferred onto petri-dish and cultured in suspension condition without bFGF removed hESC media (EB media) for 3 days. Next to investigate the effect of Activin-A, EBs were subsequently cultured in EB media supplement with 100 ng/ml Activin-A for 3 days. After 5～7 days of Activin-A treatment, cystic EBs began to appear which increased in numbers reaching ～60% of initially formed EBs over 5 days. Endoderm lineage marker, AFP were highly expressed and specifically localized at the surface region of cystic EBs comparison with normal EBs. We next attached the cystic EBs onto gelatin-coated plates and cultured for 5 days. In the results of real-time PCR and immunocytochemistry analysis, AFP-expressing cells migrated and localized at the outgrowth region of attached cystic EBs. To obtain the AFP-expressing cells of the outgrowth region, we manually isolated by using micro- dissection and cultured them. These cells strongly express AFP over 70% of isolated cells post re-plating. Here, we first showed an expression pattern of specifically localized ELCs by Activin-A during differentiation of hESCs. From this observation, we could highly purified ELCs from undifferentiated hESCs. Taken together, our system will provide a novel and efficient option to generate ELCs from hESCs.

팽이 버섯의 인공재배가 시작된 이래 재배품종의 시초는 갈색버섯이었으나, 그 후 순백계 품종이 일본에서 개발되어 현재 세계적으로 재배 생산되는 대부분의 백색 팽이버섯은 유연관계가 매우 가깝게 나타나고 있으며, 로열티 문제에서도 자유롭지 못한 것이 사실이다. 그동안 우리나라에서 개발된 팽이 품종은 기존 백색계통의 선발에 의한 '팽이1호'와 '팽이 2호'가 있었으며, 처음 단핵균주간 교잡에 의해 개발된 '백설', 갈색과 백색을 교잡한 후 다시 백색으로 여교잡에 의하여 육성된 '백로'가 육성된 바 있다. 갈색품종으로는 단핵균주간 교잡으로 '갈뫼'가 육성 보급되었다. 이번에 육성된 백아는 갈색계통간 교잡에 의하여 우리 고유의 백색계통을 최초로 개발하여 이 계통을 이용하여 육성하였기 때문에 기존의 일본 유래의 백색계통에서 벗어난 한국형 백색 품종이라 할 수 있다. '백아'의 주요특성으로 균사배양 최적온도는 25-30일이며, 버섯발생온도는 12-14℃, 자실체 생육온도는 6~7℃이다. 자실체의 갓 색깔은 백색으로 다발성이며 품질이 우수하고, 자실체 대가 단단하고 곧으며 굵고 길며 식미감이 좋은 특성을 가지고 있다. 균긁기후 발이까지 7일정도 소요 되며 병당(850ml) 수량은 111 ± 34g로 전형적인 병재배용 백색 팽이 품종이라고 할 수 있다.

최근에 폭설로 인한 온실의 붕괴가 빈번해져서 농가의 피해가 증가되고 있다. 히지만 폭설로 인한 온실의 붕괴를 막기 위한 정확한 구조해석에 대한 연구가 미약하여 매년 농가의 피해는 되풀이 되고 있다. 기존 온실의 구조해석 방법은 미소변위에 기초한 선형탄성해석으로 이루어지고 있다. 그러나 실제 온실의 강성은 건축 구조물의 강성에 비해 상당히 약하지만 하중은 폭설에 의해 상대적으로 크게 작용하여 변형이 크게 발생하고 구조물의 기하학적 형태가 변하므로 변형률-변위 관계가 비선형 거동을 한다. 본 연구에서는 폭설에 따른 온실의 붕괴를 막기 위하여 농가에서 많이 사용되는 농가 지도형 G형 단동온실과 농가보급형인 1-2W 기본형 연동온실에 대해 시간에 따른 하중단계별 기하학적 비선형 효과를 고려하여 온실의 정확한 거동분석과 구조적 안전성을 평가하는데 대변위해석 방법을 제시하고자한다.

Mesenchymal stem cells (MSCs) have the multipotent capacity and this potential can be applied for obtaining valuable cell types which can use for cell therapy on various regenerative diseases. However, insufficient availability of cellular source is the major problem in cell therapy field using adult stem cell sources. Recently, human embryonic stem cells (hESCs) have been highlighted to overcome a limitation of adult cellular sources because they retain unlimited proliferation capacity and pluripotency. To use of hESCs in cell therapy, above all, animal pathogen free culture system and purification of a specific target cell population to avoid teratoma formation are required. In this study, we describe the differentiation of a mesenchymal stem cell-like cells population from feeder-free cultured hESCs(hESC-MSCs) using direct induction system. hESC-MSCs revealed characteristics similar to MSCs derived from bone marrow, and undifferentiated cell markers were extremely low in hESC-MSCs in RT- PCR, immunostaining and FACS analyses. Thus, this study proffer a basis of effective generation of specialized human mesenchymal stem cell types which can use for further clinical applications, from xenofree cultured hESCs using direct induction system.

The electrocatalytic characteristics of oxygen reduction reaction of the PtxM(1-x) (M = Co, Cu, Ni) supported on multi-walled carbon nanotubes (MWNTs) have been evaluated in a Polymer Electrolyte Membrane Fuel Cell (PEMFC). The PtxM(1-x)/MWNTs catalysts with a Pt : M atomic ratio of about 3 : 1 were synthesized and applied to the cathode of PEMFC. The crystalline structure and morphology images of the PtxM(1-x) particles were characterized by X-ray diffraction and transmission electron microscopy, respectively. The results showed that the crystalline structure of the Pt alloy particles in Pt/MWNTs and PtxM(1-x)/MWNTs catalysts are seen as FCC, and synthesized PtxM(1-x) crystals have lattice parameters smaller than the pure Pt crystal. According to the electrochemical surface area (ESA) calculated with cyclic voltammetry analysis, Pt0.77Co0.23/MWNTs catalyst has higher ESA than the other catalysts. The evaluation of a unit cell test using Pt/MWNTs or PtxM(1-x)/MWNTs as the cathode catalysts demonstrated higher cell performance than did a commercial Pt/C catalyst. Among the MWNTs-supported Pt and PtxM(1-x) (M = Co, Cu, Ni) catalysts, the Pt0.77Co0.23/MWNTs shows the highest performance with the cathode catalyst of PEMFC because they had the largest ESA.

This writing is to understand some trends and its meaning of Regionalism Architecture in Jeju Island since 1950's.This thesis began with an interestin the identity crisis implicitin the simultaneous striving formodernism and the so-called regionalvalues in Jeju Island.Regionalism is a response in architecturalterms to re-establish continuity in a given place between pastand presentforms,and also a uniqueresultrelated to particularplaces,culturesand climatesin region.Thisisone wayoflookingattheissuesofregionalidentity. Thestudy began by observing thegeneralcharacteristicsofcontemporary ideason Regionalism inJejuarchitecture.Thismeansthattracingthehistoryofdevelopmentof Regionalism architecture in research area is notthe focus ofthis thesis.The thesis demonstratesthatRegionalism architecturesin Jeju showssometrendsrelated to the local cultural elements (or ideas) such like traditionalarchitectural forms,natural environment,local construction-materials,etc.In summation,in the perspective of Regionalism architecture,mostofbuildingsin Jeju bring outthem only asvernacular architectureasitwasonceproduced,by thesimplecombination andimitation without anycreativeinteractionoftheregionalculture. Istressthe pointin thispaperthat,in overthelastfifty years,therehavebeen very narrowed attemptstodesign theregionalvaluesin themain,and alsopointout thatthereareproblemsinthemannerinwhichlocalarchitectshavegoneabouttrying to define the regional themes.So,a grate depth is required to understand the phenomenonthatJejuareaiswithitsvariousnuancesoftraditions,art,culture,climate and lightand then to reinterpretitinto the modern building type with allthe high sense.In addition to that,someconclusionsarereached on futuredirectionsand the significanceofthestudy.