• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5350-5355
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• 2012

Human tyrosinase (hTyr) catalyzes the first and rate limiting step in the biosynthesis of a skin color determinant, melanin. Although a number of cosmetic companies have tried to develop hTyr inhibitors for several decades, absence of 3D structure of hTyr make it impossible to design or screen inhibitors by structure-based approach. Therefore, we built a 3D structure by comparative modeling technique based on the crystal structure of tyrosinase from Bacillus megaterium to provide structural information and to search new hit compounds from database. Our model revealed that two copper atoms of active site located deep inside and were coordinated with six strictly conserved histidine residues coming from four-helix-bundle. Substrate binding site had narrow funnel like shape and its entrance was wide and exposed to solvent. In addition, hTyr-tyrosine and hTyr-kojic acid, a well-known inhibitor, complexes were modeled with the guide of solvent accessible surface generated by in-house software. Our model demonstrated that only phenol group or its analogs could fill the binding site near the nuclear copper center, because inside of binding site had narrow shape relatively. In conclusion, the results of this study may provide helpful information for designing and screening new anti-melanogenic agents.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.5
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• pp.738-747
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• 2018

Objective: In a previous study, analysis of Illumina sequenced metagenomic DNA data of bacteria in Vietnamese goats' rumen showed a high diversity of putative lignocellulolytic genes. In this study, taxonomy speculation of microbial community and lignocellulolytic bacteria population in the rumen was conducted to elucidate a role of bacterial structure for effective degradation of plant materials. Methods: The metagenomic data had been subjected into Basic Local Alignment Search Tool (BLASTX) algorithm and the National Center for Biotechnology Information non-redundant sequence database. Here the BLASTX hits were further processed by the Metagenome Analyzer program to statistically analyze the abundance of taxa. Results: Microbial community in the rumen is defined by dominance of Bacteroidetes compared to Firmicutes. The ratio of Firmicutes versus Bacteroidetes was 0.36:1. An abundance of Synergistetes was uniquely identified in the goat microbiome may be formed by host genotype. With regard to bacterial lignocellulose degraders, the ratio of lignocellulolytic genes affiliated with Firmicutes compared to the genes linked to Bacteroidetes was 0.11:1, in which the genes encoding putative hemicellulases, carbohydrate esterases, polysaccharide lyases originated from Bacteroidetes were 14 to 20 times higher than from Firmicutes. Firmicutes seem to possess more cellulose hydrolysis capacity showing a Firmicutes/Bacteroidetes ratio of 0.35:1. Analysis of lignocellulolytic potential degraders shows that four species belonged to Bacteroidetes phylum, while two species belonged to Firmicutes phylum harbouring at least 12 different catalytic domains for all lignocellulose pretreatment, cellulose, as well as hemicellulose saccharification. Conclusion: Based on these findings, we speculate that increasing the members of Bacteroidetes to keep a low ratio of Firmicutes versus Bacteroidetes in goat rumen has resulted most likely in an increased lignocellulose digestion.

• IMMUNE NETWORK
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• v.1 no.1
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• pp.77-86
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• 2001

Background: Hepatitis C virus(HCV), a family of Flaviviridae, has a host cell-derived envelope containing a positive-stranded RNA genome, and has been known as the maj or etiological agent for chronic hepatitis, hepatic cirrhosis, and hepatocellular carcinoma. There remains a need to dissect a molecular mechanism of pathogenesis for the development of therapeutic and effective preventive measure for HCV. Identification of cellular receptor is of central importance not only to understand the viral pathogenesis, but also to exploit strategies for prevention of HCV. This study was aimed at identifying peptide mimotopes inhibiting the binding of E2 protein of HCV to MOLT-4 cell. Methods: In this study, phage peptide library displaying a random peptides consisting of 7 or 12 random peptides was employed in order to pan against E2 protein. Free HCV particles were separated from the immune complex forms by immunoprecipitation using anti-human IgG antibody, and used for HCV-capture ELISA. To identify the peptides inhibiting E2-binding to MOLT-4 cells, E2 protein was subj ect to bind to MOLT-4 cells under the competition with phage peptides. Results: Several phage peptides were selected for their specific binding to E2 protein, which showed the conserved sequence of SHFWRAP from 3 different peptide sequences. They were also able to recognize the HCV particles in the sera of HCV patients captured by monoclonal antibody against E2 protein. Two of them, showing peptide sequence of HLGPWMSHWFQR and WAPPLERSSLFY respectively, were revealed to inhibit the binding of E2 protein to MOLT-4 cell efficiently in dose dependent mode. However, few membrane-associated receptor candidates were seen using Fasta3 programe for homology search with these peptides. Conclusion: Phage peptides containing HLGPWMSHWFQR and WAPPLERSSLFY respectively, showed the inhibition of E2-binding to MOLT-4 cells. However, they did not reveal any homologues to cellular receptors from GenBank database. In further study, cellular receptor could be identified through the screening of cDNA library from MOLT-4 or hepatocytes using antibodies against these peptide mimotopes.

• Journal of Acupuncture Research
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• v.28 no.6
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• pp.1-17
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• 2011

Objectives : This study aimed to review randomized controlled trials of acupuncture performed in South Korea that used sham acupuncture as a control group. Methods : The following databases were searched through the end of September 2011: Koreanstudies information service system (KISS), Korean medical database (KMbase), national discovery OR science leaders (NDSL), oriental medicine advance searching integrated system (OASIS), and research information service system (RISS). The following search terms were used: acupuncture AND (sham or placebo). The reference lists of searched articles and Korea institute of oriental medicine (KIOM) reports(2005~2009) were identified. The following data were extracted: year/first author, disease, number of participants, blinding, intervention, outcome, and result. Where appropriate, we performed meta-analysis. The methodological quality was assessed according to the Jadad scale and 'risk of bias' by Cochrane Handbook procedure. Results : Twenty-nine studies were included in this review. In eighteen studies, penetrating sham controls were used as the control intervention, whereas the remaining eleven studies adopted non-penetrating sham controls such as the Park Sham Device or blunt auricular acupuncture. Nine studies showed statistically significant difference in outcomes. Twelve studies concerning insomnia after stroke, chronic tension-type headache, idiopathic Parkinson's disease, Hwa-Byung, and smoking cessation were included in meta-analysis. A meta-analysis of insomnia after stroke only found significant difference(MD -4.31, 95% Cl -6.19 to -2.42, $p$<0.00001). In general, all of the studies showed low methodological quality(Jadad score: mean 2.1). Risk of bias by Cochrane Handbook procedure varied. Conclusions : The results of this study could not suggest conclusive evidence that acupuncture is more effective than sham acupuncture in several diseases. In the future, more studies with rigorous acupuncture trials using sham controls should be conducted.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3503-3507
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• 2013

Background: Although the majority of investigations concerned with TP53 and its protein have focused on coding regions, recently a set of studies highlighted significant roles of regulatory elements located in p53 mRNA, especially 5'UTR. The wrap53${\alpha}$ transcript is one of those that acts as a natural antisense agent, forming RNA-RNA hybrids with p53 mRNA and protecting it from degradation. Materials and Methods: In this study, we focused on the mutation status of exon $1{\alpha}$ of the WRAP53 gene (according to exon 1 of p53) in 160 breast tumor tissue samples and conducted a bioinformatics search for probable miRNA binding site in the p53/wrap53 overlapping region. Mutations were detected, using single stranded conformation polymorphism (SSCP) and sequencing. We applied the miRBase database for prediction of miRNAs which target overlapping region of p53/wrap53 transcripts. Results: Our results showed all samples to have wild type alleles in exon 1 of TP53 gene. We could detect a novel and unreported intronic mutation (IVS1+56, G>C) outside overlapping regions of p53/wrap53 genes in breast cancer tissues and also predict the presence of a binding site for miR-4732-5p in the 5'UTR of Wrap53 mRNA. Conclusions: From our findings we propose designing further studies focused on overexpression of miRNA-4732-5p and introducing different mutations in the overlapping region of wrap53 and p53 genes in order to study their effects on p53 and its ${\Delta}N$ isoform (${\Delta}$40p53) expression. The results may provide new pieces in the p53 targeting puzzle for cancer therapy.

• Journal of Korea Spatial Information System Society
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• v.7 no.1 s.13
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• pp.63-76
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• 2005

Recently, the wireless positioning techniques and mobile computing techniques were developed with rapidly to use location data of moving objects. Also, the demand for LBS(Location Based Services) which uses location data of moving objects is increasing rapidly. In order to support various LBS, a system that can store and retrieve location data of moving objects efficiently is required necessarily. The more the number of moving objects is numerous and the more periodical sampling of locations is frequent, the more location data of moving objects become very large. Hence the system should be able to efficiently manage mass location data, support various spatio-temporal queries for LBS, and solve the uncertainty problem of moving objects. Therefore, in this paper, we presented a hash technique, a clustering technique and a trajectory search technique to manage location data of moving objects efficiently And, we have developed a Mass Moving Object Location Data Management System, which is a disk-based system, that can store and retrieve location data of mass moving objects efficiently and support the query for spatio-temporal data and the past location data with uncertainty. By analying the performance of the Mass Moving Object Locations Management system and the SQL-Server, we can find that the performance of our system for storing and retrieving location data of moving objects was about 5% and 300% better than the SQL-Server, repectively.

• Journal of Information Management
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• v.33 no.1
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• pp.31-47
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• 2002

The main purpose of this research is to look into not only how users evaluate two major databases(BIST and SATURN) of the scientific and technical literature in Korea, but also what users expect from scientific and technical information services in general. The result of the user evaluation shows that there is a very little difference between two databases in database quality. It was found that BIST is better than SATURN in terms of accuracy, customer support, searching capability, and currency, whereas SATURN is preferred to BIST for completeness and the average number of retrieved items. User expectation for scientific and technical information is also investigated by surveying its user community. Among three user groups, there is notable disagreement in language uses to search non-korean literature. Each group also shows different demands for translation of original literature. This study attempted to evaluate the quality of the scientific and technical information (BIST and SATURN) and simultaneously to investigate users demands in general. By doing so, the specificity implied in quality evaluation of specific information services as well as the generalization of the users behaviors in scientific and technical community were accommodated in this study.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.1
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• pp.122-131
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• 1992

An expert system is developed which can design the power transmission involute cylindrical gears on the basis of strength and durability. Bending strength, surface durability, scoring, and wear probability are considered as the basis. The basic components of the expert system are knowledge base, inference engine, and working memory. The knowledges in knowledge base are classified hierarchically into the knowledges used in selection of gear type, selection of materials, and determination of K factor and are represented by rules. In the inference engine two inference methods are implemented with the depth first search method. For-ward chaining method is introduced in the selection of gear type and materials and in the determination of K factor. Backward chaining method is introduced in the detailed design of module and face width in accordance with the validation of strength. And inference efficiency is achieved by constructing the part needing a lot of numerical calculations in strength estimation separately from inference mechanism. The working memory is established to save the results during inference temporarily. In addition, design database of past design results is built for consultation during design and knowledge acquisition facility, explanation facility, and user interface are included for the usefulness of user. This expert system is written with the PROLOG programming language and the FORTRAN language in numerical calculation part which interfaced with PROLOG and can also be executed on IBM-PC compatible computer operated by MS-DOS alone.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.501-510
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• 2010

The knowledge base on emotional information is one of the key elements in the implementation of emotion retrieval systems for contents design of Mobile devices. This study proposed a new approach to the knowledge base implementation by automatically extracting color components from full-color images. In this study, the validity of the proposed method was empirically tested. Database was developed using 100 interior images as visual stimuli and a total of 48 subjects participated in the experiment. In order to test the reliability of the proposed 'emotional information knowledge base', firstly 'recall ratio' that refers to frequencies of correct images from the retrieved images was derived. Secondly, correlation Analysis was performed to compare the ratings by the subjects to what the system calculated. Finally, the rating comparison was used to run a paired-sample t-test. The analysis demonstrated satisfactory recall ration of 62.1%. Also, a significant positive correlation (p<.01) was observed from all the emotion keywords. The paired Sample t-test found that all the emotion keywords except "casual" retrieved the images in the order from more relevant to less relevant images and the difference was statistically significant (t(9)=5.528, p<.05). Findings of this study support that the proposed 'emotional information knowledge base' established only with color information automatically extracted from images can be effectively used for such visual stimuli search tasks as commercial interior images.

• Journal of Korea Multimedia Society
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• v.11 no.3
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• pp.315-322
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• 2008

Searching a location of the copied video in video database, signatures should be robust to video reediting, channel noise, time variation of frame rate. Several kinds of signatures has been proposed. Ordinal signature, one of them, is difficult to describe the spatial characteristics of frame due to the site of fixed window, $N{\times}N$, which is compute the average gray value. In this paper, I studied an algorithm of sequence matching in video copy detection for the copyright protection, employing the R-tree index method for retrieval and suggesting a robust ordinal signatures for the original video clips and the same signatures of the pirated video. Robust ordinal has a 2-dimensional vector structures that has a strong to the noise and the variation of the frame rate. Also, it express as MBR form in search space of R-tree. Moreover, I focus on building a video copy detection method into which content publishers register their valuable digital content. The video copy detection algorithms compares the web content to the registered content and notifies the content owners of illegal copies. Experimental results show the proposed method is improve the video matching rate and it has a characteristics of signature suitable to the large video databases.