• Journal of Life Science
• /
• v.23 no.1
• /
• pp.137-142
• /
• 2013

Human adipose-derived mesenchymal stem cells (hMSCs) are highly useful for vascular regeneration of injured or inflamed tissue. Lipopolysaccharide (LPS) is a potent activator of macrophages and stimulates macrophages to release inflammatory cytokines. In the present study, we explored the role of LPS-activated macrophages in the differentiation of hMSCs to smooth muscle cells (SMCs). We demonstrated that conditioned medium from LPS-induced macrophages (LPS CM) stimulates differentiation of hMSCs to SMCs, as evidenced by increased expression of smooth muscle-specific markers, including alpha-smooth muscle actin (${\alpha}$-SMA), smooth muscle-myosin heavy chain, and calponin. LPS induced the secretion of $PGF2{\alpha}$ from macrophages, and $PGF2{\alpha}$ treatment stimulated expression levels of SMC-specific markers in hMSCs. Furthermore, small interfering RNA-mediated silencing of the $PGF2{\alpha}$ receptor inhibited LPS CM-stimulated ${\alpha}$-SMA expression. These results suggest that LPS-activated macrophages promote differentiation of hMSCs to SMCs through a $PGF2{\alpha}$-dependent mechanism.

• Journal of the Korean earth science society
• /
• v.25 no.5
• /
• pp.327-335
• /
• 2004

The purpose of this study was to investigate the effect of cooperative skill training on problem based learning for elementary school science class. Two experiment groups were involved, in which problem based learning model was used and control group, in which traditional instruction was employed. One of experiment groups was trained in cooperative skills before the instruction. The results demonstrated a significant main effect in the scores of achievement and a significant interaction effect between the instructional strategies and learning ability level. The performance of high-level students in the two experimental groups was higher than that of control group. However, the performance of medium and low-level students trained with cooperative skills training was higher than that of students without cooperative skills training. A significant main effect was also found in self-esteem, but there was no significant interaction between instructional strategies and learning ability. Therefore, this study suggests that cooperative skills training is of great importance for minimizing the free-rider effect and increasing collaborative interaction in cooperative learning.

• Journal of The Korean Association For Science Education
• /
• v.23 no.5
• /
• pp.458-469
• /
• 2003

Hypothesis is defined as a proposition intended as a possible explanation for an observed phenomenon. The purpose of this study was to generate a grounded theory on the process of undergraduate students' generating hypothesis-knowledge about scientific episodes. Three hypothesis-generating tasks were administered to four college students majored in science education. The present study showed that college students represented five types of intermediate knowledge in the process of hypothesis generation, such as question situation, hypothetical explicans, experienced situation, causal explicans, and final hypothetical knowledge. Furthermore, students used six types of thinking methods, such as searching knowledges, comparing a question situation and an experienced situation, borrowing explicans, combining explicans, selecting an explican, and confirming explicans. In addition, hypothesis-generating process involves inductive and deductive reasoning as well as abductive reasoning. This study also discusses the implications of these findings for teaching and evaluating in science education.

• Korean Journal of Breeding Science
• /
• v.41 no.4
• /
• pp.451-455
• /
• 2009

Lilium lancifolium, which is one of the Korean native lilies, possesses several useful genetic characteristics such as growth vigor, bulbil formation and resistance to Fusarium. Hybridization was performed to insert useful traits of Asiatic hybrid "Dreamland" as the male parent with upward direction and dark brown spotless on the petal into L. lancifolium as the female parent. The rate of pollen germination of L. lancifolium and "Dreamland" were 30% and 60%, respectively. The pollen germination ratio of $F_1$ progenies at flowering date was 25-57%, which is between the parents'pollen germination ratio. The individual flowering time was between 113 days and 131 days after planting. Of 99% of all plants, the leaf shape index was more than five, which means that the leaf shape of $F_1$ plants is more influenced by female than male parent. The flower color was separated into four types. 51.5% of the progenies showed orange and 44.2% showed light orange, respectively. The colors seemed to be highly influenced by female parents. Mixed colors of parents, orange yellow and light yellow orange, were 3.1%, 1.2%, respectively. Flowering directions were segregated by three different ways, upside, side, and downside. Side direction, which is medium type between female and male parent, was 73%. All progenies showed lots of spot on petals except one offspring. The percentage of bulbil formation on leaf axil was 49.4%. Among those, the maximum number of bulbil formation was 25. The mean number of bulbil formation per plant was five.

• Journal of The Korean Association For Science Education
• /
• v.27 no.5
• /
• pp.367-378
• /
• 2007

The purpose of this study is to investigate the features of science language in Earth science textbooks and Earth science research articles. We examined two Earth science textbooks and two Earth science articles using the taxonomy of scientific words, the text structure analysis of explanations, the analysis of conjunctive relations and reasoning, and the function of conjunction. The results showed that school science language revealed in Earth science textbooks had high proportion of naming words and the text structures in which definition/exemplification structure and description structure were dominant. Also, internal relations that showed additional arrangement rather than logical inference, were predominant in Earth science textbooks. However, scientists' science language revealed in the Earth science articles had more proportion of process words and concept words than the Earth science textbooks and the schematic structure of explanation texts, such as orientation - implication sequence - conclusion. In addition, the text structures in each sentences of implication -sequence showed cause/effect or problem-solving after description structures. Also each sentences expressed causal or abductive reasoning through the internal relations using verbs or adverbial inflection. It is necessary that we bridge the gap between the two languages for students' authentic use of science language. For the bridging, we propose "interlanguage", which mediates between school science language and scientists' language.

• Journal of KIISE:Computer Systems and Theory
• /
• v.36 no.4
• /
• pp.311-325
• /
• 2009

This paper presents a method for analyzing Hangul glyphs with their outline fonts and obtaining intermediate fonts with two different fonts. The glyphs are represented and analyzed hierarchically such as characters, components(letters) and strokes. With the analysis results, we obtain several intermediate glyphs by morphing two different glyphs of same character. For a natural glyph contour morphing, we employ the curve morphing algorithm by weighted mean of strings. In addition, we provide four operations for transformation of glyphs with different topology. As a result, it is illustrated that the proposed Hangul glyphs morphing scheme is useful for new font generation from any exist fonts or handwritings.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.7
• /
• pp.799-803
• /
• 2010

The KDB-tree is a traditional indexing scheme for retrieving multidimensional data. Much research for KDB-tree family frequently addresses the low storage utilization and insufficient retrieval performance as their two bottlenecks. The bottlenecks occur due to a number of unnecessary splits caused by data insertion orders and data skewness. In this paper, we propose a novel index structure, called as $KDB_{CS}^+$-tree, to process skewed data efficiently and improve the retrieval performance. The $KDB_{CS}^+$-tree increases the number of fan-outs by exploiting bit-vectors for representing splitting information and pointer elimination. It also improves the storage utilization by representing entries as a hierarchical structure in each internal node.

• Journal of Korean Society of Forest Science
• /
• v.89 no.1
• /
• pp.18-23
• /
• 2000

Leaves of various, 3 to 5-year-old Quercus hybrids were intermediate in size between their parental species. The petiole length was the smallest in the hybrids of Q. dentata ${\times}$ Q. crispula $F_1$ and was intermediate in the hybrids of Q. aliena ${\times}$ Q. serrata $F_1$ and Q. dentata ${\times}$ Q. aliena $F_1$ between their parents. The number of serration in hybrids was close to their mother tree's in most of crossing combinations. The serration depth and the ratio between longitudinal and transverse length of leaves were intermediate between the values of their parental species.

• Venture DIGEST
• /
• s.95
• /
• pp.40-41
• /
• 2006

행복한 인생은 하나의 과학이다. 행복이란 저절로 이루어지는 것이 아니라 '구체적인 계획'과 이에 따른 '지속적인 행동' 그리고 '성취'라는 연결고리를 통해서 나오는 결과물이기 때문이다. 지금부터 2006년 인생의 중간 점검에 들어가 보자. 이 작업은 당신의 희망찬 후반전을 구상하는 '2006년 하프타임 워크숍'이다.

• The Journal of Natural Sciences
• /
• v.8 no.1
• /
• pp.47-51
• /
• 1995

Several intermediate glasses are investigated to bond the alumina and the hydroxyapatite (HAp). The chemical compositions of the intermediate glasses are chosen as $CaO-Al_2O_3$. The mole ratio of CaO/$Al_2O_3$ is changed from 0.5 to 3.0. The lowest melting is observed at $1355^{\circ}C$ in the specimen of CaO/$Al_2O_3$ at the mole ratio of 2. With increasing contents of $Al_2O_3$, the melting temperatures gradually increase and a number of pores are observed. The sectional microstructure shows that the good wetability is observed in higher contents of CaO specimens. This implies that the good wetability is obtained in the mole ratio range of CaO/$Al_2O_3geq2$. The phase transformations are observed after treatment but the major peaks of HAp still exist.