• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.510-515
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• 2006

The putative EPA synthesis gene cluster was mined from the entire genome sequence of Shewanella oneidensis MR-1. The gene cluster encodes a PKS-like pathway that consists of six open reading frames (ORFs): ORFSO1602 (multi-domain beta-ketoacyl synthase, KS-MAT-4ACPs-KR), ORFSO1600 (acyl transferase, AT), ORFSO1599 (multi-domain beta-ketoacyl synthase, KS-CLF-DH-DH), ORFSO1597 (enoyl reductase, ER), ORFSO1604 (phosphopentetheine transferase, PPT), and ORFSO1603 (transcriptional regulator). In order to prove involvement of the PKS-like machinery in EPA synthesis, a 20.195-kb DNA fragment containing the genes was amplified from S. oneidensis MR-1 by the long-PCR method. Its identity was confirmed by the methods of restriction enzyme site mapping and nested PCR of internal genes orfSO1597 and orfSO1604. The DNA fragment was cloned into Escherichia coli using cosmid vector SuperCos1 to form pCosEPA. Synthesis of EPA was observed in four E. coli clones harboring pCosEPA, of which the maximum yield was 0.689% of the total fatty acids in a clone designated 9704-23. The production yield of EPA in the E. coli clone was affected by cultivation temperature, showing maximum yield at $20^{\circ}C$ and no production at $30^{\circ}C$ or higher. In addition, production yield was inversely proportional to glucose concentration of the cultivation medium. From the above results, it was concluded that the PKS-like modules catalyze the synthesis of EPA. The synthetic process appears to be subject to regulatory mechanisms triggered by various environmental factors. This most likely occurs via the control of gene expression, protein stability, or enzyme activity.

• Journal of Korean Elementary Science Education
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• v.40 no.1
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• pp.81-99
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• 2021

The purpose of this study is to develop scientist vignettes and to explore their effects to change students' perceptions of scientists, scientific attitudes, and the nature of science. The scientist vignettes developed in this study include research cases on seven scientists, including British zoologist Jane Goodall. Each vignette consists of 4 to 6 pages in consideration of the reading level of elementary school students, and contains illustrations describing the main contents of the text. In addition, scientist vignettes contain descriptions on terms and text boxes explaining the higher concepts, and each vignette contains questions that students can think deeply based on the story of the scientist. To verify the educational effectiveness of scientist vignettes, we investigated changes in their perceptions of scientists, scientific attitudes, and the nature of science in 564 elementary school students. We conducted group interviews with four elementary school teachers. As a result of conducting pre-test and post-test using a narrative questionnaire consisting of 6 questions, students became more sophisticated in the understanding of the science and the characteristics of scientists after experiencing scientist vignettes and their understanding the nature of science changed into a more modern epistemological perspective. Also, in a group interview with teachers, teachers assessed that scientist vignettes would positively affect the understanding of science process skills and the nature of science, and forming a scientific attitude, especially in increasing understanding of the nature of science. We discussed ways to effectively utilize scientist vignettes in elementary school science education based on these result.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.4
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• pp.342-352
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• 2021

Objectives: This study analyzed the local exposure levels of radiation emitted from the equipment with soft X-ray ionizers to investigate the radiation exposure levels in Liquid Crystal Display(LCD) manufacturing processes. Methods: This study measured the local radiation levels for the equipment installed in two LCD manufacturing companies. The equipment were installed at diverse processes and equipped with various number of ionizers. The local radiation levels were measured on the surface of the equipment by using direct reading equipment, and the measurements were converted into annual effective dose by considering the radiation exposure time of workers. Statistical analyses were performed to investigate the radiation exposure characteristics. Results: Annual effective doses for 97.6% of the equipment being measured were less than 1 mSv. However, the range of annual effective doses was 0.004 mSv ~ 2.167 mSv, which indicated a large variation among the equipment. Statistical analyses of the study found that this large variation was raised due to improper shielding of the equipment rather than process and/or equipment characteristics. To pinpoint the cause of this large variation in annual effective dose, this study improved the shielding of the equipment being radiated over 1 mSv and found that their average effective dose was reduced from 1.604 mSv to 0.126 mSv after shielding improvement. Conclusions: Relatively high exposure levels of radiation were observed in some equipment where their shielding were insufficiently thick and/or sealed. This finding implies that the shielding of the equipment is an important engineering countermeasure to control the radiation exposure levels in industries.

• Journal of English Language & Literature
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• v.56 no.4
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• pp.667-690
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• 2010

This essay attempts to read Percy Bysshe Shelley s The Mask of Anarchy by attending to a political agenda that Shelley seeks to propose and embody in the poem. This poem was written as a response to an exceptional political event, the Peterloo Massacre, and thus it is evident that Shelley intended to engage in contemporary politics by writing this poem. As many critics have pointed out, however, the way in which this poem addresses social, plitical issues is ambivalent and even confusing, since it contains many elements that contradict each other, and sometimes its political visions are based on incoherent conceptions. For this reason, this poem has been considered to be a failure as an occasional poem which should provide the reader with a clear direction for political actions. Faced with this critical problem, this essay proposes that the ambivalence this poem reveals-e.g., the confrontation between moderate artistic fantasy and radical tenets-is not a retreat from political activism, as some critics suggested, but a result of its creation and embodiment of a public sphere which invites various social classes and their positions. The mode in which Shelley conceives this unified public sphere in the course of writing The Mask of Anarchy can be interpreted in terms of the following three features. First, this poem underscores the significance of thoughts in constituting a communal space between people, thus asking the reader to participate in this process of thinking on given issues. Second, this poem suggests that people should enlighten each other by engaging in communicative reciprocations. Lastly, the public sphere formulated by the previous two features should incorporate various socio-political agents beyond class boundaries (even oppressors themselves) into its own working field. After explaining how these three features are manifested in the poem, this essay argues that the unified public sphere thus formed in the poem is the very agenda that Shelley aims to propose for the contemporaneous politics and culture. As a conclusion, this essay highlights how Shelley s project of creating a unified public sphere finally failed in contemporary history through observing two contrasting receptions of Shelley s works.

• Korean Journal of Child Studies
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• v.6 no.2
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• pp.21-33
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• 1985

This study was conducted to ascertain whether a didactic mode of instruction, favored students who indicated a preference for left hemispheric information processing. The subjects were 50 fifth grade students whose California Achievement Test score percentile ranks were between 50 - 80. They were randomly selected from one elementary school in Chapel Hill, NC, USA. All Ss completed the Form CC of "Your Style of Learning and Thinking" (Torrance and McCarthy, 1980) which is a paper/pencil inventory designed to categorize the subjects according to their hemispheric preference for processing information; right hemisphere, left hemisphere, and integrated. Then all Ss received a didactic mode of instruction, a verbal question/answer followed by teacher's reading of a fictional animal story, "The Chinese Bee-eater". After completion of instruction, the Ss were asked to respond to eighteen open-ended questions about the animal. Eight of the 50 subjects were found to fall into the right hemisphere style of information processing group; fourteen into left; and fourteen into integrated. The remaining fourteen could not be assigned to either of these three categories and were not included in the analysis of the results. the mean scores of the comprehensive test among hemispheric groups and among sex groups. A two way analysis of variance also presented no significant differences among the hemispheric preference combined by sex groups. These results failed to prove the research hypothesis that students who indicate a preference for left hemispheric information processing will have higher scores on a comprehensive test after receiving a didactic mode of instruction, the so-called left style of instruction. Some limits in research process and conceptual confusion about hemisphericity were discussed. Finally, it was suggested that educators need to be more careful in drawing educational implications from neurological hemispheric research.

• Journal of Korean Library and Information Science Society
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• v.50 no.2
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• pp.169-189
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• 2019

The purpose of this study was to elicit the priority of the index of the operation evaluation of the school library, and to present measures for improvement of the evaluation index that reflects the project sites. To this end, the school library evaluation index was analyzed by applying the Analytic Hierarchy Process(AHP) analysis method to teacher librarians who are the representative personnel of the school library. According to the research, the priority of the upper tier evaluation areas was human resources, library services, information resources, library management, facilities and environment, and the priority of the lower tier evaluation items was human resource allocation, human resources expertise, reading education, information literacy education, efforts to activate education, book composition snowflake, the latest book, budget, facility access, book status, appropriateness of facilities and facilities, management plan, proximity accessibility, PR and marketing, school library steering committee, cooperation, use of materials current status. The conclusions drawn from this study could be used as basic data in the application of fieldworked school library assessment indicators.

• Korean journal of communication and information
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• v.65
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• pp.27-50
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• 2014

This paper analyzed how people of Late Chosun Dynasty communicated through the 8 Korean novels with the assumption that the fictitious world of novels reflect the social circumstances of that time. In oral communication, hierarchical relationship of kin was the most important variable. Between strangers social status was the most important variable. The communication between people and the authorities was performed mostly by oral because the majority of people were illiterate. In village community, information on the common interest diffused by oral communication in bank of stream, parish pump and auberges. Through this process the public opinion of community was formed. In media communication diverse patterns were performed, such as letters, written materials, and diary. Contrary to the western culture, it was analyzed that written material was taken more reliable than oral communication. The fact that reading diaries of others were permitted showed that the concept of privacy had not existed yet. Books were used for the purposes of education and leisure. In conclusion it can be said that the communication of people in Late Chosun Dynasty was mainly by oral communication and supplemented by written materials.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.135-143
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• 2011

In the Doritaenopsis hybrid, like most of the orchid species and hybrids, temperature is crucial for the vegetative-to-reproductive transition, and low temperature is required for bud differentiation. To understand the molecular mechanism of this process, an orchid GIGANTEA (GI) gene, DhGI1, was isolated and characterized by using the rapid amplification of cDNA ends (RACE) PCR technique. Sequence analysis showed that the full-length cDNA is 4,022 bp with a major open reading frame of 3,483 bp, and the amino acid sequence showed high similarity to GI proteins in Zea mays, Oryza sativa, Arabidopsis thaliana and other plants. Semi-quantitative RT-PCR revealed that DhGI1 was expressed throughout development and could be detected in roots, stems, leaves, peduncles and flower buds. The expression level of DhGI1 was higher when the plants were flowering at low temperature (22/$18^{\circ}C$ day/night) than the other growth stages. Further analysis indicated that the accumulation of DhGI1 transcripts was significantly increased at low temperature, and concomitantly, initiation of the peduncle was observed. However, DhGI1 levels were low under high temperature (30/$25^{\circ}C$) conditions, and flower initiation was inhibited. These results indicate that the expression of DhGI1 is regulated by low temperature and that DhGI1 may play an important role in inflorescence initiation in this Doritaenopsis hybrid at low temperatures.

• Development and Reproduction
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• v.21 no.3
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• pp.237-247
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• 2017

Mammalian spermatogenesis occurs in a precise and coordinated manner in the seminiferous tubules. One of the attempts to understand the detailed biological process during mammalian spermatogenesis at the molecular level has been to identify the testis specific genes followed by study of the testicular expression pattern of the genes. From the subtracted cDNA library of rat testis prepared using representational difference analysis (RDA) method, a complimentary DNA clone encoding type III member of a DnaJ family protein, DnaJC18, was cloned (GenBank Accession No. DQ158861). The full-length DnaJC18 cDNA has the longest open reading frame of 357 amino acids. Tissue and developmental Northern blot analysis revealed that the DnaJC18 gene was expressed specifically in testis and began to express from postnatal week 4 testis, respectively. In situ hybridization studies showed that DnaJC18 mRNA was expressed only during the maturation stages of late pachytene, round and elongated spermatids of adult rat testis. Western blot analysis with DnaJC18 antibody revealed that 41.2 kDa DnaJC18 protein was detected only in adult testis. Immunohistochemistry study further confirmed that DnaJC18 protein, was expressed in developing germ cells and the result was in concert with the in situ hybridization result. Confocal microscopy with GFP tagged DnaJC18 protein revealed that it was localized in the cytoplasm of cells. Taken together, these results suggested that testis specific DnaJC18, a member of the type III DnaJ protein family, might play a role during germ cell maturation in adult rat testis.

• Journal of Technologic Dentistry
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• v.34 no.3
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• pp.213-220
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• 2012

Purpose: The aim of this study was to determine the repeatability and reproducibility of two dental scanners. Methods: The master die and the stone replicas(Kavo, Germany) were digitized in touch-probe scanner(Incise, Renishaw, UK), white light scanner(Identica, Medit, Korea) to create 3-dimensional surface-models. The number of points in the point clouds from each reading were calculated and used as the CAD reference model(CRM). Discrepancies between the points in the 3-dimensional surface models and the corresponding CRM were measured by a matching-software(Power-Inspect R2, Delcam Plc, UK). The t-student test for one samples were used for statistical analysis. Results: The reproducibility of both scanner was within $3{\mu}m$, based on mean value. The mean value between measurements made directly on the touch probe scanner digital models and those made on the white light scanner digital models was $2.20-2.90{\mu}m$, and was statistically significant(P<0.05). Conclusion: With respect to adequate data acquisition, the reproducibility of dental scanner differs. Three-dimensional analysis can be applied to differential quality analysis of the manufacturing process as well as to evaluation of different analysis methods.