Lithographically-featured photonic microparticles of colloidal assemblies

Lee, Su Yeon,Kim, Shin-Hyun,Heo, Chul-Joon,Hwang, Hyerim,Yang, Seung-Man Royal Society of Chemistry 2010 Physical Chemistry Chemical Physics Vol.12 No.38

<P>We have described a new and promising strategy for the fabrication of composite and porous photonic crystal microparticles that combines the self-assembly of colloidal particles with photolithography techniques. We fabricated silica/SU-8 composite microparticles with photonic bandgaps <I>via</I> four steps: (1) deposition of the silica colloidal crystals on the photoresist, (2) embedding of the colloidal crystals in the photoresist, (3) UV exposure through a photomask and subsequent development, and (4) release of the microparticles from the substrate. Embedding was performed above the glass transition temperature (<I>T</I><SUB>g</SUB>) of uncrosslinked SU-8. At such temperatures, capillary forces on the silica particles facilitate the migration of colloidal crystals in the SU-8 matrix. Particle migration ceased when the top colloidal crystal layer was trapped at the interface between air and SU-8. In addition, we also prepared porous microparticles with an inverse opaline structure by dissolving the embedded silica particles from the composite structures. The porous microparticles showed enhanced reflectivity at the bandgap position due to the large refractive index contrast. The bandgap position of the microparticles was controlled by the size of the silica particles, which determined the lattice constant. Bilayered composite and porous microparticles with two distinct photonic bandgaps were also prepared by sequential deposition of colloidal crystals composed of two differently sized silica particles.</P> <P>Graphic Abstract</P><P>A new and promising fabrication strategy of photonic crystal microparticles was demonstrated by combining colloidal self-assembly with photolithography. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c0cp00134a'> </P>

연령·표상양식·단어유형이 유아산문학습에 미치는 효과

황구연,최민수,정연숙 진주교육대학교 1990 論文集 Vol.34 No.1

The learning activities of young children have been frequently accomplished through the prose materials varied in the form and the structure. The probe passages mean the language activities that explain, describe, and tell about the objects and events in several sentences. It is needed the concrete materials and the method of instruction in order that young children understand the abstract and complex informations and concepts in prose. The materials of instruction for young children's prose learning involve the pictures, the actions, and the written language that are similar or identical with the prose contents. Thus it is possible to study the relations between Bruner's three repersentational modes (enactive, iconic, symbolic) and the young children's prose learning. The main purpose of this study was to present the appropriate instruction media and method in young children's prose learning by investigating the effects of the repersentational modes, the area, and the kinds of word on young children's memory of key words in prose learning. And the other purpose was to give the basic information in selecting the words for instruction throuh the comparison of nouns and adjectives. The hypotheses of this study are as follows: Hypothesis 1. The young children win recall key words differently in ages. Hypothesis 2. The young children win recall key words better in the conditions of enactive representation and iconic representation than in the condition of symbolic representation, Hypothesis 3. The five, six, seven-year-olds will recall more nouns than adjectives. Hypothesis 4. There win be the interaction effect of the ages and the representational modes. Hypothesis 5. There win be the interaction effect of the representational modes and the kinds of word. For subjects in this study, a total of 90 children who know the written language and go to the kindergarten and the elementary school in Guang-Ju, Ma-San were randomly assigned to the three experimental conditone (actions, pictures, witten languages). The experimental instruments were the actions, the 10 pictures, and the 10 cards with the written languages, and the tapes with the prose passages by the experts. Stein's(1978) "Albert Gets Caught" was used for this study as in Jung Yeon-Suk'a paper(1986). The datas were colleted by the response test consisted of ten items that were divided to 0. 1. and 2 degrees by the responses. The collected dates were analized by the repeated 3×3×2 (Ages × Rrpesentational Modes × Kinds of Word) ANOVA. The following findings were obtained: First, the hypothesis 1 was accepted [F(2, 81) = 1.09, p<,01]. The seven-year-olds (the second grades) rememberd key words better then the five-year-olds and the six-year-olds. But the differonce between the memory of the five- year-olds and that of the six-year-olds was not. Second, the hypothesis 2 was accepted [F(2, 51) = 5.56, P<.01]. Namely the significant differences among the conditions of the notions, the pictures, and the written languages were. The means of the three conditions were 6.78, 6.98, 5.92. And be the mean of the iconic repersentation mods was highest. Third, the hypothesis 3 was sccepted [F(1,81) = 39.68. P<.01]. This indicates the main effect of the kinds of word. And this mians that the kinds of word affect the prose learning of the five, six, and seven-year-olds. Forth, the hypothesis 4 was rejected. the degrees in the three representational modes were consistent in disregard of ages. Fifth, the hypothesis 5 was accepted [F(2, 81) = 3.01, P<.10]. The young children remembered relatively well key words of adjectives in the iconic representation mode.

UR 이후의 농산물가격정책 방향

황연수 東亞大學校生命資源科學大學附設 農業資源硏究所 1994 農業生命資援硏究 Vol.3 No.1

The Korean government had tried to maintain agricultural product prices at the low level to keep wages low and thus stabilize industrial commodity prices for sustaining international competitiveness. As a result, the Korean agriculture now faces a deep crisis. In addition, the import liberalization of the agricultural commodities and the reduction of the domestic agricultural support level caused by the Uruguay Round agricultural negotiations will deepen the crisis. The objective of this study is to provide policy directions for the achievement of the price policy objectives such as the reduction of price and income instability, the increase of the food self-sufficiency, and the enhancement of the level of prices and incomes. The major findings of the study are summarized as follow : 1. By 'Agreement of Agriculture' of UR and 'Schedule' of Korea. "Total Aggregate Measurement of Support(AMS)" will be reduced from 1,719 billion won to 1,490 billion won(the reduction of 13.3 percent) during the implementation period(1995∼2004). However, if the government minimizes the agricultural import by the measures such as 'special safeguard provisions', 'sanitary and phytosanitary measures', 'countervailing duties', 'state trading enterprise', etc. and maintains the current level of the domestic support by the measures such as 'more favourable treatment for developing country', 'domestic support policies for which exemption from the reduction commitments : public stockholding for food security purposes, domestic food aid, direct payments to producers, decoupled income support, etc.', and 'De-minimis', the price policy could be continued at the current size and level. 2. Ten years' grace period might be the last opportunity for the survival of Korean agriculture. The price and the quantity of the government procurement should be kept at the proper level so that the farmers only concentrate on the commodity choice and production management, just like the agricultural price policy programs of the EU and the U.S. 3. Price policy is still important for the coordination of the time lag between the structural adjustment and the cost-down, for the provision of personnels in charge of the structural adjustment. And the price policy should not be subordinated to the structure policy and the general price control policy. 4. For the balanced development of agriculture, the system of goal and measures by commodity should be established and the level and balance should be implemented to the price and profitability by commodity.

梅泉의 交遊를 통한 意識世界 硏究

柳年錫,黃秀貞 順天大學校 師範大學 附屬 科學敎育硏究所 2002 科學과 敎育 Vol.10 No.-

This study covers the life of "Maecheon Hwang―hyeon", who was one of the last scholars in the Chosum Dynasty, along with his social intercourse. ChapterⅡ summarizes the findings in related to his social intercourse. His social intercourse are divided into two categories in terms of area ; Local area (his home town) and Central area (capital of that time). In kwnagyang he kept company with local scholars, who helped him to consolidate his own unique poetic styles and literary world. ChapterⅢ he kept close relationship with those days' respectable scholars. Through the friendly and beneficial company, he not only got rich in social experiences, but also, he could open the new horizon, through which he became well―known with widely ranged view points of the society. In conclusion, Maecheon, one of the greatest writers, accomplished literary mastery that absorbed the pains of folks those days, along with contribution to upgrading confucian literature.

농업소득 안정화을 위한 직접지불제 도입 방안

박진도,황연수 東亞大學校生命資源科學大學附設 農業資原硏究所 1996 農業生命資援硏究 Vol.5 No.1

Farm price and income instability will reemerge as a major problem of agriculture in the post Uruguay Round period. The Korean government attempts to introduce the various types of direct payment allowed by WTO, and the farm income stabilization program is one of those. The objective of this study is to examine necessities for and devices of farm income stabilization program. The major findings of the study are summarized as follows: 1. Considering Agreement on Agriculture of UR, foreign examples and characteristics of korean agriculture, it is desirable to introduce a whole-farm income stabilization program like Canadian NISA(Net Income Stabilization Account) rather than programs by commodity. 2. The farm income stabilization program recommended in this study is a voluntary program that helps producers save money in good times to stabilize their incomes when farm revenues drop. In the program, producers deposit funds(1.5% of gross receipts) into their own account and receive a matching contribution(3% of gross receipts) from the government. 3. By introducing this program, stabilization and support of the farm income, increase of food production and maintenance of regional society are expected. Opinion survey showed that 80 percent of regional experts were in favor of this program. 4. The problems to be solved in the process of the program include conflicts with other programs, low participation rate of farmers, moral hazard in investigating eligible gross receipts, and administrative and technical difficulties.

Inoue Balloon을 이용한 PMV의 장·단기 결과 분석

진은선,이연아,전숙,김현숙,정승묵,박상선,최락경,임달수,홍석근,황흥곤 대한순환기학회 2003 Korean Circulation Journal Vol.33 No.11

Capsicum chinense, 재래종 및 저항성 고추 유전자원에서 역병 저항성 계통 선발

김정훈,여승호,김동우,배수연,한정혜,황희숙,김병수 慶北大學校農業科學技術硏究所 2002 慶北大農學誌 Vol.20 No.-

2000년도에 검정에서 역병에 살아남은 개체들로부터 채종하여 육성한 Capsicum chinense 31계통에 대하여 역병 저항성을 검정한 결과 고도의 저항성을 나타내는 것은 발견되지 않았다. 2001년도의 검정에서 역병에 살아남은 개체로부터 채종한 재래종 26계통에 대하여 다시 역병 저항성 검정을 실시한 결과 KC180, KC230, KC195, KC194에서 다수의 개체가 살아남아 저항성을 나타내었다. 그러나 KC180과 KC230은 각각 AC2258과 CM334와 혼종된 것으로 관찰되었다. KC195와 KC194는 재래종의 형질을 유지하고 있는 것으로 관찰되었다. CM334의 보존 증식과정에 자연교잡이 일어난 것으로 보여 이의 순도향상을 위하여 채종년도별로 시료를 꺼내어 역병저항성 검정을 실시한 결과 가장 오래된 1992년도 채종종자에서부터 약간의 이형주가 관찰도기 시작하여 1995년부터 2001년도까지 시간이 경과함에 따라 많이 변형되어 있는 것을 알 수 있었다. 1992년도 종자에서 이형주를 제거하고 원형의 개체로부터 자식종자를 대량으로 채종하였다. 함께 공시한 AC2258은 순수한 것으로 확인되었다. 1995년도 채종 CM334 종자에서는 비록 혼종은 되었으나 측지발생이 적은 개체들이 발견되어 이들을 개체 선발하여 역병에 저항성이며 측지발생이 적은 계통으로 육성하고 있다. A total of 31 c. chinense lines selected from 2000 screening were tested again for resistance to P. capsici but resistance was not found in the lines. A total of 26 selections from Korean land races tested 2001 spring were tested again for resistance to P. capsici. KC180, KC230, KC195 and KC194 showed moderate resistance to P. capsici. However, it was apparent on the basis of hortivultural characteristics that KC180 and KC230 had been naturally crossed with AC2258 and CM334, respectively. CM334 and AC2248 seed lots that were increased in different years were taken out and tested for resistance to improve their genetic purity because the resistant genetic resources have been showing some off-types in the population. Off-types began to be found in 1992 seed lots and the proportion and degree of the offs was increasing with time up to 2001. Plants true to the type in 1992 seed lots were selected and their inbred seeds were mass produced in a net cage in the greenhouse. AC2258 included in the experiment number of lateral branching at cotyledonary axil, although they were off from the original in the experiment together was uniform. In 1995 seed lost of CM334, plants with resistance to P. capsici and low or no number of lateral branching at cotyledonary axil, although they were off from the original CM334, were found and selection was applied to breed lines fixed in the characters.

TAZ as a novel enhancer of MyoD-mediated myogenic differentiation

Hwang, Eun Sook,Jeong, Hana,Bae, Su jung,An, Su Yeon,Byun, Mi Ran,Hwang, Jun Ha,Yaffe, Michael B,Hong, Jeong-Ho 梨花女子大學校 藥學硏究所 2011 藥學硏究論文集 Vol.- No.21

Myoblast differentiation is indispensable for skeletal muscle formation and is governed by the precisely coordinated regulation of a series of transcription factors, including MyoD and myogenin, and transcriptional coregulators. TAZ (transcriptional coactivator with PDZ-binding motif) has been characterized as a modulator of mesenchymal stem cell differentiation into osteoblasts and adipocytes through its regulation of lineage-specific master transcription factors. In this study, we investigated whether TAZ affects myoblast differentiation, which is one of the differentiated lineages of mesenchymal stem cells. Ectopic overexpression of TAZ in myoblasts increases myogenic gene expression in a MyoD-dependent manner and hastens myofiber formation, whereas TAZ knockdown delays myogenic differentiation. In addition, enforced coexpression of TAZ and MyoD in fibroblasts accelerates MyoD-induced myogenic differentiation. TAZ physically interacts with MyoD through the WW domain and activates MyoD-dependent gene transcription. TAZ additionally enhances the interaction of MyoD with the myogenin gene promoter. These results strongly suggest that TAZ functions as a novel transcriptional modulator of myogenic differentiation by promoting MyoD-mediated myogenic gene expression.

Health effects from exposure to dental diagnostic X-ray

Su-Yeon Hwang,Eun-Sil Choi,Young-Sun Kim,Bo-Eun Gim,Mina Ha,Hae-Young Kim 환경독성보건학회 2018 환경독성보건학회지 Vol.33 No.-

The purpose of this review is to summarize the results of studies on of the association between exposure to dental X-rays and health risk. To perform the systematic review, We searched the PUBMED, EMBASE, and MEDLINE databases for papers published before December 15, 2016. A total of 2 158 studies, excluding duplicate studies, were found. Two reviewers independently evaluated the eligibility of each study. The final 21 studies were selected after application of exclusion criteria. In terms of health outcomes, there were 10 studies about brain tumors, 5 about thyroid cancer, 3 about tumors of head and neck areas, and 3 related to systemic health. In brain tumor studies, the association between dental X-ray exposure and meningioma was statistically significant in 5 of the 7 studies. In 4 of the 5 thyroid-related studies, there was a significant correlation with dental diagnostic X-rays. In studies on head and neck areas, tumors included laryngeal, parotid gland, and salivary gland cancers. There was also a statistically significant correlation between full-mouth X-rays and salivary gland cancer, but not parotid gland cancer. Health outcomes such as leukemia, low birth weight, cataracts, and thumb carcinomas were also reported. In a few studies examining health effects related to dental X-ray exposure, possibly increased risks of meningioma and thyroid cancer were suggested. More studies with a large population and prospective design are needed to elaborate these associations further.

Synthesis and in vitro characterizations of porous carboxymethyl cellulose-poly(ethylene oxide) hydrogel film

Su Yeon Lee,Sumi Bang,Sumi Kim,Seong Yeon Jo,Bumchul Kim,Yunjae Hwang,노인섭 한국생체재료학회 2015 생체재료학회지 Vol.19 No.2

Background: Cellulose and its derivatives such as carboxymethyl cellulose (CMC) have been employed as a biomaterial for their diverse applications such as tissue engineering, drug delivery and other medical materials. Porosity of the scaffolds has advantages in their applications to tissue engineering such as more cell adhesion and migration leading to better tissue regeneration. After synthesis of CMC-poly(ethylene oxide) (PEO) hydrogel by mixing the solutions of both CMC-acrylate and PEO-hexa-thiols, fabrication and evaluation of a CMC-PEO gel and its film in porous form have been made for its possible applications to tissue regeneration. Physicochemical and biological properties of both CMC-PEO hydrogel and porous films have been evaluated by using physicochemical assays by SEM, FTIR and swelling behaviors as well as in vitro assays of MTT, Neutral red, BrdU, gel covering and tissue ingrowth into the pores of the CMC-PEO gel films. Degradation of CMC-PEO hydrogel was also evaluated by treating with esterase over time. Results: Chemical grafting of acrylate to CMC was verified by analyses of both FTIR and NMR. CMC-PEO hydrogel was obtained by mixing two precursor polymer solutions of CMC-acrylate and PEO-hexa-thiols and by transforming into a porous CMC-PEO gel film by gas forming of ammonium bicarbonate particles. The fabricated hydrogel has swollen in buffer to more than 6 times and degraded by esterase. The results of in vitro assays of live and dead, MTT, BrdU, Neutral red and gel covering on the cells showed excellent cell compatibility of CMC-PEO hydrogel and porous gel films. Furthermore the porous films showed excellent in vitro adhesion and migration of cells into their pore channels as observed by H&E and MT stains. Conclusions: Both CMC-PEO hydrogel and porous gel films showed excellent biocompatibility and were expected to be a good candidate scaffold for tissue engineering.