• BMB Reports
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• v.53 no.10
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• pp.521-526
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• 2020

Endogenous retroviruses (ERVs) are retrotransposons present in various metazoan genomes and have been implicated in metazoan evolution as well as in nematodes and humans. The long terminal repeat (LTR) retrotransposons contain several regulatory sequences including promoters and enhancers that regulate endogenous gene expression and thereby control organismal development and response to environmental change. ERVs including the LTR retrotransposons constitute 8% of the human genome and less than 0.6% of the Caenorhabditis elegans (C. elegans) genome, a nematode genetic model system. To investigate the evolutionarily conserved mechanism behind the transcriptional activity of retrotransposons, we generated a transgenic worm model driving green fluorescent protein (GFP) expression using Human endogenous retroviruses (HERV)-K LTR as a promoter. The promoter activity of HERV-K LTR was robust and fluorescence was observed in various tissues throughout the developmental process. Interestingly, persistent GFP expression was specifically detected in the adult vulva muscle. Using deletion constructs, we found that the region from positions 675 to 868 containing the TATA box was necessary for promoter activity driving gene expression in the vulva. Interestingly, we found that the promoter activity of the LTR was dependent on che-1 transcription factor, a sensory neuron driver, and lin-15b, a negative regulator of RNAi and germline gene expression. These results suggest evolutionary conservation of the LTR retrotransposon activity in transcriptional regulation as well as the possibility of che-1 function in non-neuronal tissues.

• The Mathematical Education
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• v.56 no.1
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• pp.119-130
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• 2017

The purpose of this study is to explain the long term growth and development of elementary teachers' Professional Learning Communities(PLC) about mathematics implemented on an institutional basis. Especially, it is meaningful to analyze and present the development process and characteristics of PLC, which was started by the basis on the collaboration of a National University of Education and its affiliated elementary school. In this study, PLC activities during three years were analyzed according to the capacities and dimensions of a professional learning community. The developmental capacity of the PLC analyzed in this study can be summarized as follows. In the first year, development of organizational competence in terms of capacity, resources, structure, and system of exchanges was the main factor in personal competence, and the development of individual competence began to share collective learning and practice. In the second year, personal exchanges were active in all the topics of activities, and personal level competence was activated such that more activities of critical knowledge formation were performed on an individual level. On the basis of the development of the individual level formed in the second, individual competence and organizational capacity developed. Factors that have influenced the development of capacities of PLC include: disclosure of activities outside the community, participation in outsiders, provision of procedures to share equal participation and leadership, voluntary and critical participation of teachers, improvement of mathematics teaching methods, sharing themes and visions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.3
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• pp.153-159
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• 2007

We studied oocyte steroidogenesis in relation to oocyte development in the greenling, Hexagrammos otakii, a marine multiple spawner. Vitellogenic and mature oocytes were incubated in vitro in the presence or absence of $[^3H]-17\;{\alpha}-hydroxyprogesterone$ as a precursor. The major metabolites were androgens [androstenedione $(A)_4)$ and testosterone (T)] and estrogens [$17\;{\beta}-estradiol\;(E_2)$ and estrone ($E_1$)] in vitellogenic oocytes. The metabolic rate of T was lower in 1.08 to 12-mm oocytes, while that of $E_2$ increased with oocyte size. The endogenous productions of T, $E_2$ and 17 ${\alpha}-hydroxy$, 20 ${\beta}-dihydroprogesterone\;(17{\alpha}20{\beta}OHP)$ were quantified using a radioimmunoassay in the non-precursor group. The endogenous levels of T and $E_2$ were highest in 1.08 to 12-mm oocytes and $17{\alpha}20{\beta}OHP$ was produced only in 1.90 to 95-mm oocytes. The relationship between oocyte size and steroidogenesis showed that 1.08 to 12-mm oocytes are full vitellogenic following induction of the maturation process. Moreover, $17{\alpha}20{\beta}OHP$ acts as a maturation inducing hormone in H. otakii.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.65-70
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• 2014

The aim of this study was to identify the chronological growth characteristics of Gaeryangmeoru grapes, by observation of the developmental process of the axillary bud, fruit quality, and anatomical structure of the pericarp. No necrosis of axillary buds was observed, irrespective of node position of the shoot, from shoot occurrence to leaf fall. Berry weight, cluster weight, soluble solid content and titratable acidity were analyzed to be 1.2 g, 128.8 g, $16.9^{\circ}Brix$, and 1.57%, respectively, at maturity. The sugar was composed of fructose and glucose, with a ratio of 1:1 (fructose: glucose) at maturity. Malic acid was predominant among the organic acids, and conformed to the changes of chronological titratable acidity. Sugar and organic acid content changed dramatically starting a week before veraison. The degraded ovules were observed before and after fertilization, and the pericarp was composed of one epidermis, and seven to ten hypodermis layers at maturity.

• Biomedical Science Letters
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• v.10 no.4
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• pp.515-521
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• 2004

To measure regional cerebral blood volume (rCBV) with perfusion MR imaging of cerebral fat embolism by neutral fat and free fatty acids in cats. Triolein (group 1, n=15), oleic acid (group 2, n=9) and linoleic acid (group 3, n=11) were infused into unilateral internal carotid artery using microcatheter through the transfemoral approach. PVA particle was used as a non-fat embolic material in a control group (group 4, n=9). Perfusion-weighted MR image was obtained at 30 minutes and 2 hours postembolization, based on T2-and diffusion-weighted images. The data of lesion and contralateral normal area were transferred to personal computer, time-to-signal intensity curve was drawn and trans for used to △R2/sup */ curve in regular order. The process in the personal computer was done by using the author's developmental image processing program and interactive data language (IDL) softwares. Statistical significance was approved by paired t-test and ANOVA. rCBV of the lesion was decreased comparing to the normal area in all groups. The ratios of rCBV were as follows (group No, at 30 minutes, at 2 hours); group 1,32％, 51％; group 2, 30％, 44％; group 3, 39％, 61％; group 4, 21％, 36％. rCBVs of 2 hours was significantly increased compared to those of 30 minutes in all groups (P<0.005). rCBV was decreased at 30 minutes in cerebral fat embolism and recovered a little, but significantly at 2 hours. Perfusion-weighted images was useful method in offering hemodynamic information in cerebral fat embolism.

• Fashion & Textile Research Journal
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• v.18 no.4
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• pp.399-411
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• 2016

This research reviewed the developmental process of domestic outdoor wear and later analyzed the images given out by men's outdoor wear. The research results are as follows. First, military supplies left by American soldiers were dyed or reformed and then worn, and daily wear were mainly worn in the 1960s. Wears made from light and waterproof materials were worn and equipments were used in the 1970s. High functioning materials which allowed simultaneous breathability, waterproof and thermal insulation functions were used for wears in the 1980s. For the jacket especially, functionality was enhanced sith zippers, snaps and velcro to prevent cold air penetration in the 1990s. Florescent piping decorations and logo decorations, and prints and colors which reflected the trend, were used to emphasize fashionity and decorativeness in the 2000s. Second, Sophisticated image emphasized urban feeling with toned-down windbreaker jackets without much detail, with down jacket and pants. Casual image expressed a relaxed feeling with windbreaker jacket, shirts, jumper, vest and pants made of cotton, mesh knit and denim. Active image emphasized functionality by brightly colored windbreaker jackets, down jacket and pants. Ethnic image expressed an exotic mood with windbreaker jackets with stylized prints, with jumper, down jacket and pants. Military image showed a strong masculine feeling with jackets adorned with epaulettes, khaki colors and camouflage prints, with jumper, T-shirts, vest, shorts and pants. Avantgarde image exuded an experimental and unique feeling with jackets made of various colors and materials, such as cotton, jersey and glossy materials, with down jacket and jersey pants.

• Communications of Mathematical Education
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• v.27 no.3
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• pp.321-339
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• 2013

This study is basic research about actualizing mathematical teaching and learning based on storytelling that is raised for reforming school mathematics education. We have developed mathematics textbook model for 2nd grade in middle school based on storytelling. It was applied in the middle school classroom and the results were analyzed. In order to develop the mathematics textbook model, the procedures and methods of development were extracted from the literature. And mathematics textbook model was developed in accordance with the process and methods. To apply it in school 20 hours of instruction were carried out. For the analysis of the results, we conducted a questionnaire survey, the teachers' interview, the affective test and math anxiety test. Through the results of this study, we will be able to check the possibility of storytelling in mathematics class. And it will be also the foundation of mathematics teaching and learning based on storytelling in middle school.

• ALGAE
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• v.18 no.3
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• pp.217-223
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• 2003

Seasonal growth and maturation process of Caulerpa okamurae were investigated in natural populations and in culture. Monthly sampling was carried out by SCUBA diving at Baekunpo, Busan, southeastern coast of Korea from November 1999 to October 2001. Growth of erect branches depended mainly on the water temperature in the natural habitat. Maximum length of erect branches was 14.0 $\pm$ 1.4 cm in June 2001 when the water temperature was 19.7$^{\circ}C$ and minimum was 2.8$\pm$0.2 cm in April when the water temperature was 14.7$^{\circ}C$. Fresh weight of erect branches was 3.9 $\pm$ 0.5 g in June 2001 and 0.2 $\pm$ 0.04 g in September 2000. Biomass of the population was maximum of 922.5 g dw${\cdot}m^{-2}$ in July and minimum of 125.6 g dw${\cdot}m^{-2}$ in April. Gametangial network was observed on the ramuli when the water temperature was over 19$^{\circ}C$ in August 2000 and June 2001. In the culture regime of 4 temperatures (15, 20, 25 and 30$^{\circ}C$) and 3 irradiances (20, 50 and 80 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$) combination, the maturation of excised erect branches was mainly affected by temperature. Maturation was induced under all irradiance conditions at 20 and 25$^{\circ}C$; under 80 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$ at 15$^{\circ}C$; and under 20 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$ at 30$^{\circ}C$. The highest rate of maturation was 64% under 20 $\mu$mol${\cdot}m^{-2}{\cdot}s^{-1}$ at 25$^{\circ}C$. These results suggested that developmental initiations of C. okamurae occurred at higher than 13$^{\circ}C$ and maturation took about 270 degree-days.

• Journal of Information Technology Application
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• v.3 no.2
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• pp.83-102
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• 2001

Internet-based shopping business spread rapidly in Korea. Companies are trying to develop and use various strategic competences. The strategies employed by those companies include activities related to the design of shopping site, market positioning, assistance of purchasing process, payment mechanism, and provision of various consumer services. However, the success of these strategies depends on various environmental factors and internal capability of the companies. In this study, I examined four successful Internet shopping mall companies and compared them to draw useful guidelines for Internet-based intermediary business. These four companies were selected because they are all considered successful by now, but brought different background. We found follows. First, each company tried to economize their own historical and developmental background. All of the selected companies were alike in their focus on the whole Internet user group. Customer needs analysis was performed more systematically. The Importance of customer information and the use of it are not sufficient. Second, Each companies consistently emphasized the importance of market-related activities. Despite the differences in initial states, all companies used similar strategies and had similar focus in target market and products. Conclusively, implications from this research for Internet shopping business can be summarized as follows. First, One of the important future directions for Internet shopping mall business is to broaden target market. Second, the provisions of carefully designed customized services are one success factor. Third, As customer traffic increased, the provision of differential customer service becomes a key success factor.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.127-135
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• 1999

Cryopreservation is able to store the surplus pre-embryos for freezing and furthermore thawing and transfer in a subsequent cycle. Cryopreserving cells which are maintaining their viability are the very complex process. This study has been carried out in order to find the effects of cryopreservation steps, freezing media and embryonic stages on the rates of viability and development of cryopreserved mouse embryos. Female ICR mice ($6{\sim}8$ weeks old) were induced to superovulate by sequential intraperitoneal injection of 5 IU PMSG and 5 IU hCG 48h apart. Mouse embryos were collected according to its developmental stage after the injection of hCG. Embryos were cryopreserved not only by cryoprotectant step (1 step${\sim}$4 step) but also in a variety of media (HTF, IVF medium, D-PBS) and cell stage. The results were as follows: There is no clear advantage in these freezing media of rapid method, but 4 cell and 8 cell of slow method (2, 3, 4 step) have advantage in D-PBS. The development of embryos according to cell stage become greater in 8 cell stage. In the treatment steps of cryopreservation, the development of embryo to blastocyst was similar among rapid method, but the development of 4 cell and 8 cell embryos to blastocyst according to slow method was better than rapid method.