• Korean Journal of Plant Tissue Culture
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• v.24 no.1
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• pp.1-35
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• 1997

Fertilized egg, by successive cell divisions, differentiates into different tissues and organs with various structures and functions. Different cells and tissues contain different proteins, products of selective gene expression. Not all the genes in any genomes are equally active, temporal and spatial gene expression being the general rule. Present paper attempts to review the tanscriptional mechanisms or the initiations of transcription from several angles. In some of the organisms the genes in the process of transcription or the genes in the inactive state can be seen under the light microscope. Some bands of Drosophila polytene chromosomes may exhibit a swollen or puff appearance under certain conditions. A puff, unfolded or decondensed form of chromomere, represents sets of intense transcriptional activity or RNA synthesis. The heterochromatic X chromosome whose genes remain inactive in the female mammals can be visualized as a dark staining structure called Barr body, Configuration of chromatin differs between transcribed and nontranscribed chromatin. Modification to the chromatin facilitates RNA synthesis. The movement of large polymerase molecule along the DNA would probably be facilitated if some modifications of the chromatin configuration is effected. Methylation of cytosines in CG sequences is associated with inactive genes. Methylation can play a role in determination of mammalian cells during embryogenesis. Demethylation is necessary for the gene to be expressed during development A histone modification that is also known to be correlated with transcriptional capacity of chromatin is acetylation of the lysine residues of the core histones. Chromatin containing a high level of histone acetylation is very sensitive to DNase 1. For the transcription to occur TBP must first bind to the TATA box. Another TF, TF IIB, then binds to the promoter-TBP complex, facilitating the access of RNA polymerase to the transcription initiation site. As recently as eight years ago researchers assumed that histones were irrelevant to the regulation of gene expression. Histones combine with the DNA to form nucleosome of the chromatin. Histones are vital participant in gene regulation. Histone and basal factors compete for access to TATA box. When DNA is exposed to basal factors before histones are introduced, the basal factors assemble on TATA boxes preventing the access of histones, allowing transcription to occur, for transcription to begin, activator protein at the upstream activation sequence or enhancer must interact with the tail of histone H4 at TATA box and cause the histone role particle to dissociate from the TATA box leading to partial breakup of the histone core particle and allowing the basal factors to bind to the TATA box. New concept of genomic flux in contrast to the old concept of static genome has been developed based on the powerful new molecular techniques. Genomic changes such as repetitive DNAs and transposable elements, it is assumed but not yet proved, may affect some of the developmental patterns that characterize particular cells, tissues, organs, and organisms. In the last decade or so remarkable achievement have been made in the researches of the structures and functions of TFs and the specific target sequences located in promoters or enhancers where these TFs bind. TFs have independent domains that bind DNA and that activate transcription. DNA binding domain of TFs serves to bring the protein into the right location. There are many types of DNA binding domains. Common types of motifs can be found that are responsible for binding to DNA. The motifs are usually quite short and comprise only a small part of the protein structure. Steroid receptors have domains for hormone binding, DNA binding, and activating transcription. The zinc finger motif comprises a DNA binding domain. Leucine zipper consist of a stretch of amino acids with a leucine residue in every seventh position Two proteins form a dimer because they interact by means of leucine zippers on similar α-helical domain. This positions their DNA binding basic domains for interaction with the two halves of a DNA sequence with dyad symmetry of TGACTCA, ACTGAGT.

• Journal of Plant Biotechnology
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• v.33 no.1
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• pp.11-18
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• 2006

Salt stress is one of major environmental factors influencing plant growth and development. To identify salt tolerance determinants in higher plants, a large-scale screen was conducted with a bialaphos marker-based T-DNA insertional collection of Arabidopsis ecotype C24 mutants. One line for salt stress-sensitive mutant (referred to as ssm1) exhibited increased sensitivity to both ionic (NaCl) and nonionic (mannitol) osmotic stress in a root growth assay. This result suggests that ssm1 mutant is involved in ion homeostasis and osmotic compensation in plant. Molecular cloning of the genomic DNA flanking T-DNA insert of ssm1 mutant was achieved by mutant genomic DNA library screening. T-DNA insertion appeared in the first exon of an open reading frame on F3M18.7, which is the same as AtSYP61. SSM1 is SYP61/OSM1 that is a member of the SNARE superfamily of proteins required for vesicular/target membrane fusions and factor related to abiotic stress.

• Journal of Astronomy and Space Sciences
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• v.22 no.1
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• pp.1-12
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• 2005

The Korean VLBI Network (KVN) will open a new field of research in astronomy, geodesy and earth science using the newest three Elm radio telescopes. This will expand our ability to look at the Universe in the millimeter regime. Imaging capability of radio interferometry is highly dependent upon the antenna configuration, source size, declination and the shape of target. In this paper, imaging simulations are carried out with the KVN system configuration. Five test images were used which were a point source, multi-point sources, a uniform sphere with two different sizes compared to the synthesis beam of the KVN and a Very Large Array (VLA) image of Cygnus A. The declination for the full time simulation was set as +60 degrees and the observation time range was -6 to +6 hours around transit. Simulations have been done at 22GHz, one of the KVN observation frequency. All these simulations and data reductions have been run with the Astronomical Image Processing System (AIPS) software package. As the KVN array has a resolution of about 6 mas (milli arcsecond) at 220Hz, in case of model source being approximately the beam size or smaller, the ratio of peak intensity over RMS shows about 10000:1 and 5000:1. The other case in which model source is larger than the beam size, this ratio shows very low range of about 115:1 and 34:1. This is due to the lack of short baselines and the small number of antenna. We compare the coordinates of the model images with those of the cleaned images. The result shows mostly perfect correspondence except in the case of the 12mas uniform sphere. Therefore, the main astronomical targets for the KVN will be the compact sources and the KVN will have an excellent performance in the astrometry for these sources.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.2
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• pp.119-125
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• 2012

The tributary water quality and flowrate monitoring result, which is fundamental data for the establishment of the water environmental policy, is used as very important data for the implementation of TMDL. This study introduced how to use the tributary water quality and flowrate monitoring data for the analysis of the watersheds, the satisfactory assessment of water quality standards in the watersheds, the selection of watersheds for the establishment of the implementation plan, and the selection of the tributary catchments for improving the water quality using a stream grouping method. According to the analytical results of tributary catchment using water quality and flowrate monitoring data of thirty-seven tributaries in the Geum-River watershed at Chungcheongnam-do, the value of flowrate in the tributaries, which is located in the middle-lower Geum-River watershed, was greater than the other areas and the concentration of the water pollutants regardless of water quality parameters in the tributaries at Nonsancheon catchment was relatively higher than the other areas. The problems, which have the determination of satisfaction of water quality standards and selection of target watersheds for establishment of the implementation plan regardless of the water quality of tributary in the watershed due to the water quality and flowrate monitoring results of the main river, were improved use of the results of tributary water quality and flowrate monitoring. Also, the tributary catchments for improving the water quality, according to stream grouping method based on the results of tributary water quality and flowrate monitoring, were selected. In the Geum-River watershed at Chungcheongnam-do, the tributary in the Nonsancheon, Byeongcheoncheon, Seokseongcheon, Jocheon catchments, which has a large flow and a high concentration of water pollutants, should be preferentially selected for improving the water quality of the tributary in accordance with the reduction of the source of pollution.

• The Journal of Korean Society for Radiation Therapy
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• v.17 no.2
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• pp.113-124
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• 2005

Purpose : The using of endo-rectal balloon has proposed as optimal method that minimized the motion of prostate and the dose of rectum wall volume for treated prostate cancer patients, so we make the customized rectal balloon device. In this study, we analyzed the efficiency of the Self-customized rectal balloon in the aspects of its reproducibility. Materials and Methods : In 5 patients, for treatment planning, each patient was acquired CT slice images in state of with and without rectal balloon. Also they had CT scanning samely repeated third times in during radiation treatment (IMRT). In each case, we analyzed the deviation of rectal ballon position and verified the isodose distribution of rectum wall at closed prostate. Results : Using the rectal balloon, we minimized the planning target volume (PTV) by decreased the internal motion of prostate and overcome the dose limit of radiation therapy in prostate cancer by increased the gap between the rectum wall and high dose region. Conclusion : The using of rectal balloon, although, was reluctant to treat by patients. View a point of immobilization of prostate internal motion and dose escalation of GTV (gross tumor volume), its using consider large efficients for treated prostate cancer patients.

• Journal of The Korean Association For Science Education
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• v.19 no.3
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• pp.409-427
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• 1999

The aim of this study was to illustrate how STS-related ideas in science education have been developed historically in the context of British education, particularly focused on the period of the 19th century and the first half of the 20th century. It has been hardly considered that the basic ideas of the STS education, one of the two paradigms of current science education together with constructivism, can be traced back to the beginning of the school science education itself. far beyond some of the programs which are largely regarded as the first-developed STS programs in Britain, such as Science in Society and SISCON. The movement of Mechanics' Institute during the first half of the 19th century would be the first systematic attempt to bridge the gap between the knowledge of pure science and its practical applications, although the main target was working-class adults rather than school pupils. At the end of the first half of the 19th century, this application-focused approach of science teaching was echoed in the elementary schools by Richard Dawes, one of the early experimenters of school science. The second half of the century was in large the period of the establishment of science as one of the core elements of school curriculum, mainly by emphasizing the aspect of pure science as a means for mental training. During this period, the elements of STS education-related appeared in the subject called 'Object Lesson' in elementary schools which was practically a separate subject from those of science. After the turn of the century, triggered by the experience of World War I, the growing appreciation of the impacts of science upon society and of the necessity of the teaching of science for wider audience gave a great impact towards two new main movements, i.e. for General Science and Citizen Science. The later illustrates a typical example of the STS movement in school science during the first half of the 20th century, particularly driven by the socialistic ideas towards the relation between science and society.

• Progress in Medical Physics
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• v.26 no.4
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• pp.258-266
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• 2015

The modern radiotherapy technique which delivers a large amount of dose to patients asks to confirm the positions of patients or tumors more accurately by using X-ray projection images of high-definition. However, a rapid increase in patient's exposure and image information for CT image acquisition may be additional burden on the patient. In this study, by introducing structural similarity (SSIM) index that can effectively extract the structural information of the image, we analyze the differences between daily acquired x-ray images of a patient to verify the accuracy of patient positioning. First, for simulating a moving target, the spherical computational phantoms changing the sizes and positions were created to acquire projected images. Differences between the images were automatically detected and analyzed by extracting their SSIM values. In addition, as a clinical test, differences between daily acquired x-ray images of a patient for 12 days were detected in the same way. As a result, we confirmed that the SSIM index was changed in the range of 0.85~1 (0.006~1 when a region of interest (ROI) was applied) as the sizes or positions of the phantom changed. The SSIM was more sensitive to the change of the phantom when the ROI was limited to the phantom itself. In the clinical test, the daily change of patient positions was 0.799~0.853 in SSIM values, those well described differences among images. Therefore, we expect that SSIM index can provide an objective and quantitative technique to verify the patient position using simple x-ray images, instead of time and cost intensive three-dimensional x-ray images.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.2
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• pp.197-208
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• 2003

Objective：In this study, we hypothesized that deficit in processing rapid linguistic stimuli is at the heart of Reading Disability(RD) and deficit in response inhibition is at the heart of Attention Deficit/Hyperactivity(ADHD). We conducted experiments to identify the core cognitive characteristics of children either with RD or with ADHD or with both, using attentional tasks and phoneme differential tests. Method：In the study 1, 28 children with ADHD, 16 children with RD+ADHD were individually administered visual/auditory performance tests. Then, the differences of performance on attentional tasks between two groups were compared while IQs of two groups were controlled. In the study 2, 13 children with RD+ADHD/RD, 13 children with ADHD, and 13 normal children were administered computerized phoneme differential tests. Result：Visual attentional tasks did not distinguish an ADHD group from a RD+ADHD group. With auditory attentional tasks, however, the comorbid group showed significantly more difficulties, causing a large variance in reaction time. RD, RD+ADHD, and ADHD groups showed more errors in phoneme differential tests than a normal control group, and each group showed distinctive performance patterns. Discussion：An ADHD group had difficulty in response inhibition and sustained attention, and children who also had RD along with ADHD magnified the auditory attentional difficulties. Even though children with RD had more trouble with responding correctly to target stimuli, their responses were not significantly different from those of children with ADHD.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.10-10
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• 2017

Rice consumption has been continuously decreasing as the eating habits of Koreans have become westernized and diversified. The per capita annual rice consumption in Korea has dropped sharply from 136.4 kg in 1970 to 61.9 kg in 2016. The Korean government, therefore, has been trying to promote rice consumption by invigorating the processed food industry using rice flour. To facilitate the market for processed rice foods, it is essential to develop proper milling technology in terms of flour particle size and damaged starch content to produce high quality rice flour at competitive cost. Dry milling and wet milling are the two major processes used to produce rice flour. Although the dry milling process is relatively simple with a lower production cost, damaged starch content increases because of the high grain hardness of rice. In wet milling, the quality of rice flour is improved by reducing flour particle size as well as damaged starch content through soaking procedures. However, the production costs are high because of the additional expenses associated with the disposal of waste water, sterilization and drying of the wet flour. Recently developed technologies such as jet milling and cryogenic milling also require expensive investment and production. Therefore, developing new rice cultivars with dry milling adaptability as well as good processing properties is an important goal of rice breeding in Korea. 'Suweon 542' is a floury endosperm mutant line derived from sodium azide treatment on a high-yield, early maturing, and non-glutinous japonica rice cultivar, 'Namil'. Compared with the wild type, after dry milling process, the grain hardness of 'Suweon 542' was significantly lower because of its round and loosely packed starch granules. Also, the flour of 'Suweon 542' had significantly smaller particles and less damaged starch than 'Namil' and other rice cultivars and its particle size distribution was similar to a commercial wheat cultivar. Recently, through collaborations with nine universities and food companies, a total of 21 kinds of processed prototypes, using the dry milling flour of 'Suweon 542', were evaluated. In the production of major rice processing products, there was no significant quality difference between the flours prepared by wet milling and dry milling. Although the amount of water added to the dough was slightly increased, it was confirmed that the recipe applying the wet flour could be used without significant change. To efficiently transfer the floury endosperm characteristics of 'Suweon 542' to other commercial rice cultivars, it is essential to develop DNA marker tightly linked to the target gene. Association analysis using 70 genome-wide SSR markers and 94 F2 plants derived from 'Suweon 542'/'Milyang 23' showed that markers on chromosome 5 explained a large portion of the variation in floury grains percentage (FGP). Further analysis with an increased number of SSR markers revealed that the floury endosperm of 'Suweon 542' was directed by a major recessive locus, flo7(t), located in the 19.33-19.86 Mbp region of chromosome 5, with RM18639 explaining 92.2% of FGP variation in the F2 population. Through further physical mapping, a co-segregate and co-dominant DNA marker with the locus, flo7(t) was successfully developed, by which, thereby, breeding efficiency of rice cultivars having proper dry milling adaptability with high yield potential or useful functional materials would be improved. 'Suweon 542' maintained the early maturity of the wild type, Namil, which can be used in rice-wheat double cropping systems in Korea not only for improved arable land but also for sharing flour production facilities. In addition to the high susceptibility against major rice diseases, nevertheless, another possible drawback of 'Suweon 542' is the high rate of viviparous under prolonged rainfall during the harvesting season. To overcome susceptibility and vivipary of 'Suweon 542', the progeny lines, derived from the crosses 'Suweon 542' and 'Jopyeong', an early maturing rice cultivar with multiple resistance against rice blast, bacterial blight, and rice strip virus, and 'Heugjinju', a anthocyanin pigment containing black rice cultivar, were intensively evaluated. As the outputs, three dry milling suitable rice elite lines, 'Jeonju614', 'Jeonju615', and 'Jeonju616' were developed.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3403-3408
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• 2012

The molecular mechanisms involved in the progression of clear cell renal cell carcinomas (ccRCCs) are still unclear. The aim of this study was to analyse the relationships between expression of RALYL and clinical characteristics. In 41 paired samples of ccRCCs and adjacent normal tissues, we used real-time qPCR to evaluate the expression of RALYL mRNA. RALYL protein levels were determined in 146 samples of ccRCC and 37 adjacent normal tissues by immunohistochemistry. Statistical analysis was used to explore the relationships between expression of RALYL and the clinical characteristics (gender, age, tumor size, T stage, N stage, M stage, survival times and survival outcome) in ccRCC. In addition, these patients were follow-up period 64 months (range: 4~116months) to investigate the influence on prognosis. We found significantly differences between ccRCC tissues and normal tissues (p<0.001, paired-sample t test) in mRNA levels of RALYL. Immunohistochemistry analyses in 146 ccRCC samples and 37 adjacent normal tissues showed significantly lower RALYL protein levels in ccRCC samples (${\chi}^2$-test, p<0.001), inversely correlating with tumour size (p=0.024), T stage (0.005), N stage (p<0.001) as well as M stage (p=0.019), but not age (p=0.357) and gender (p=0.348). Kaplan-Meier survival analysis demonstrated that people with lower level of RALYL expression had a poorer survival rate than those with a higher level of RALYL expression, significantly different by the log-rank test (p=0.011). Cox regression analysis indicated that RALYL expression (p=0.039), N stage (p=0.008) and distant metastasis (p<0.001) were independent prognosis factors for the overall survival of ccRCC patients. We demonstrated that the expression of RALYL was significantly low in ccRCC and correlated with a poor prognosis in a large number of clinical samples. Our findings showed that RALYL may be a potential therapeutic target as well as a poor prognostic factor.