• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.611-624
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• 2017

The purposes of this study are to explore Iceberg(IB) model as a systems thinking analysis tool for high school students, suggest a systems thinking analysis method using rubrics and verify its validity and reliability. For this study, the theoretical basis was examined through literature analysis about IB model and rubrics of evaluating the systems thinking. And 6 high school students participated in IB model activity and were interviewed about polar climate change. In addition, quantitative tests using systems thinking scale were also conducted to support the results of the IB model activity analysis. Data obtained from IB model activity was analyzed by using the rubrics of evaluating system thinking developed by Hung (2008). The analysis results were reviewed by two professors to confirm the validity and reliability. In order to confirm the validity, correlation analysis were performed between the rubrics and the quantitative test results. Finding are as follows: Six students used the IB model to express their systems thinking in detail and the results of the systems thinking analysis of students using rubrics showed a distribution of 17~35 points. Furthermore, the results of correlation analysis between rubrics and systems thinking scale was highly correlated (Pearson product-moment is .856) on significance level from .05. Using the IB model introduced in this study, students express their systems thinking effectively and the results of the systems thinking analysis using IB model is considered to analyze validity and reliability. Based on the results of this study, implication suggests how to study the systems thinking in science education.

• Transactions on Electrical and Electronic Materials
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• v.11 no.6
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• pp.285-287
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• 2010

This paper introduces homogeneous liquid crystal (LC) orientations on chemically modulated polystyrene (PS) surfaces using various ion beam (IB) exposure times. Transparent PS was replaced with conventional polyimide material. As a non-contact process, the IB bombardment process induced LC orientation parallel to the IB process. Through x-ray photoelectron spectroscopy, it was shown that the chemical compositional changes of the IB-irradiated PS surfaces were determined as a function of IB exposure time. Using this analysis, the optimal IB bombardment condition was determined at an IB exposure time of up to 15 seconds. Moreover, thermal stability on IB-irradiated PS surfaces were carried out which showed that a relatively high IB exposure time induced a thermally stable LC alignment property.

• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.277-283
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• 2007

Embryogenic calluses derived from shoot apical meristem explants of sweetpotato were subjected to particle bombardment to generate transgenic plants for antisense expression of cDNAs encoding two different AGPase small subunit (ibAGP1 and ibAGP2). Plants were generated via somatic embryogenesis. PCR and Southern analysis demonstrated that the incorporation of ibAGP1 and ibAGP2 into the genome in an antisense orientation. Immunoblot analysis confirmed reduced levels of AGPase small subunit in transgenic plant leaves. Plants with both ibAGP1 and ibAGP2 produced a lower level of the protein than plants with ibAGP1 alone. iodine test demonstrated that transgenic plant leaves and storage root accumulated reduced amounts of starch. Iodine staining of leaf tissues indicated that transgenic plants accumulated less amount of starch than control. In accordance with western blot analysis, plants with both ibAGP1 and ibAGP2 accumulated a lower amount of starch than plants with ibAGP1 alone. Both transgenic plants exhibited a severely retarded growth, resulting in bare survival. It is suggested that disrupted expression of the gene encoding AGPase small subunit is lethal to the growth of sweetpotato contrast to other species including potato.

• Journal of Life Science
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• v.27 no.12
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• pp.1415-1420
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• 2017

The metallothionein (MT) gene (IbMT3) was selected from an EST library of suspension-cultured sweet potato cells. The MT gene, which is one of abundant ESTs in the library, is involved in stress regulation of cells and tissues. A full-length IbMT3 cDNA was obtained and analysis of its nucleotide sequence revealed that IbMT3 encoded a type 3 MT protein, based on its structural characteristics. The function of type 3 MT in plants is not yet known. Northern blot analysis showed stronger expression of IbMT3 in suspension-cultured cells than in sweet potato plant leaves. Since cell culture is known to impose a state of oxidative stress on cells, sweet potato plants were subjected to oxidative stress to investigate the transcriptional regulation of IbMT3. When the herbicide methyl viologen (MV) was administered for 6, 12, and 24 hr, IbMT3 transcription rapidly increased at 6 hr and then decreased. A cold treatment at $15^{\circ}C$ for 24 and 48 hr resulted in a gradual increase in IbMT3 expression. These findings indicate that IbMT3 expression is regulated in response to environmental and oxidative stress. IbMT3 isoform is expected to have antioxidant effects in sweet potato plants and may play an important role in cellular adaptation to oxidative stress.

• KOREAN POULTRY JOURNAL
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• v.36 no.10 s.420
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• pp.111-115
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• 2004

최근 급격한 산란 저하로 인한 피해를 상담하는 농가들이 많아진 것을 보니 N도 문지이지만 전염성 기관지염(IB)이 심상치 않은것 같다. 최근의 분무 백신은 ND도 중요하지만 IB에도 동시에 초점을 맞추고 있다는 어느 원장님을 얼마 전 만났다. 현재 발병하고 있는 IB에 대해 상당히 효과적인 대처를 하고 있다는 생각을 하게 된다. 국가적 난제인 ND도 중요하지만 IB에 대한 농가들의 경각심과 대책도 필요하다는 생각을 다시 해보면서 이에 따른 백신 분무와 관련한 몇 가지 이야기를 해보고자 한다.

• BMB Reports
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• v.44 no.4
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• pp.262-266
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• 2011

The aac(6')-Ib gene is the most prevalent gene that encodes aminoglycoside-modifying enzymes and confers resistance to tobramycin, kanamycin, and amikacin. The aac(6')-Ib-cr variant gene can induce resistance against aminoglycoside and fluoroquinolone simultaneously. Two main methods, sequence analysis and the restriction enzyme method, can detect the aac(6')-Ib-cr variant in clinical strains. We collected the 85 strains that were believed to be aac(6')-Ib positive from clinical isolates. Among them, 38 strains were the wild-type; the remaining 47 strains were the aac(6')-Ib-cr variant. Of these 47 strains, 19 simultaneously harbored aac(6')-Ib and aac(6')-Ib-cr. Our study aims to report the characteristics of the 19 strains that simultaneously harbored both genes. This study is the first investigation published in Korea of strains that included both aac(6')-Ib and aac(6')-Ib-cr variant.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.364-368
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• 2018

The R2R3-type protein IbMYB1 transcription factor is a key regulator for anthocyanin biosynthesis in the storage roots of sweet potatoes. It was previously demonstrated that the IbMYB1 expression stimulates anthocyanin pigmentation in tobacco leaves, arabidopsis and storage roots of sweet potatoes. In this study, we generated the transgenic potato plants that express the IbMYB1 genes, which accumulated high levels of anthocyanins under the control of either the tuber-specific patatin (PAT) promoter or oxidative stress-inducible peroxidase anionic 2 (SWPA2) promoter. The PAT-MYB1 transgenic lines exhibited higher anthocyanin levels in the tuber than the empty vector control (EV) or SWPA2-MYB1 plants. When combined, our results indicated that overexpression of the IbMYB1 is a highly promising strategy for the generation of transgenic plants with enhanced tissue specific anthocyanin production.

• Korean Management Science Review
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• v.17 no.3
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• pp.61-71
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• 2000

Due to the potential growing capability that reflects future value, the market value of internet business companies (IB) are still evaluated high although major players like Amazon continuously suffer losses. Then, how do investors valuate the potential growing capabilities given that traditional financial/accounting based valuation approaches seem to be inappropriate for IB. This study attempts to provide an answer to this issue. We, therefore, analyzed the predictability of various accounting and non-accounting variables for IB value. These include book value, net income, unique visitors, page view, reach rate, public float and institutional holdings. Because of being in infant stage and difficulties in obtaining necessary web traffic data, sample of 20 pure IB were selected from Korea Stock Exchange Market, KOSDAQ, and informal market. The results of this study showed that web traffic date had the strongest relationship with IB value. In particular, unique visitors and reach rate were found to be best predictors for IB value while page view was reasonable indicator. Interestingly, net income was not found to related to IB value. This calls for an attention to the typical characteristics of IB that my hinder the usage of traditional valuation approaches for IB. Another results revealed that none of both public float and institutional holdings was significantly associated with IB value, indicating market’s supply-demand factors were less important than traffic information.

• Journal of Nutrition and Health
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• v.29 no.5
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• pp.533-546
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• 1996

This study was performed to investigate the effect of breakfast regularity on eating habits, nutritional and health status in adult men and women. Also, eating habites and nutritional status expressed as percentage of recommended energy intake in IB(Irregular Breakfast group) were studied. Proportions of IB in men and women was 23.7% and 31.1%, respectively. In men, IB had irregular mealtime, overeating tendency. Also, they consumed high-fat meat and alcohol more frequently than RB (Regular Breakfast group). Total energy intake showed no significant difference between which two groups. Energy intakes from dinner and alcohol were higher in IB than in RB. Nutrient and food intakes were lower in IB than in RB. Percent body fat of IB was higher than that of RB. Weight, triglyceride and prevalence of fatty liver were higher in IB than in RB. In women, IB had irregular mealtime, and overeating tendency. Also, they had more frequent eating out and alcohol consumption. Total energy intake was lower in IB than in RB. In men, nutrient and food intakes were lower in IB than in RB. But health status showed no significant differences between two groups. In men, energy intakes from alchol and dinner were higher in +RDA group(percentage to recommended energy > 125%) than in other groups of IB. But energy intake from carbohydrate was lower in +RDA group. -RDA group (percentage to recommended energy < 75%) had Ca and vitamin A intake less than RDA. In women, +RDA group had overeating tendency. Also, they had more frequent eating out, high-fat meat, and alcohol consumption than other groups of IB. Energy intakes from dinner, snack and fat were higher in +RDA group. But -RDA group had protein and vitamin A intake less than RDA. From our study, it seemed that breakfast irregularity led to undesirable eating habits and had relation with increase of percent body fat. Breakfast regularity seemed to be very important to maintain a nutritional balance.

• Journal of Satellite, Information and Communications
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• v.9 no.1
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• pp.33-37
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• 2014

This paper introduces homogeneous liquid crystal (LC) orientations on chemically modulated polystyrene (PS) surfaces using various ion beam (IB) exposure time. Transparent PS was replaced with conventional polyimide material. As a non-contact process, IB bombardment process induced LC orientation in the direction parallel to the IB process. Through x-ray photoelectron spectroscopy, it was shown that the chemical compositional changes of the IB-irradiated PS surfaces were determined as a function of IB exposure time.Using this analysis, the optimal IB bombardment condition was determined at IB exposure time of up to 15 s. Moreover, thermal stability on IB-irradiated PS surfaces were carried out which showed that a relatively high IB exposure time induced a thermally stable LC alignment property.