• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.51.1-51.10
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• 2020

Objectives: No studies have yet assessed vibration characteristics according to endodontic file length. Accordingly, the objective of the present study was to examine the vibration characteristics according to nickel-titanium file length and to compare these characteristics between different file systems. Materials and Methods: A total of 45 root canal models were divided into 3 experimental groups (n = 15 each) based on the file system used (ProTaper Gold [PTG], ProTaper Next, or WaveOne Gold [WOG]). Each experimental group was further divided into 3 subgroups according to file length (21, 25, or 31 mm). An electric motor (X-SMART PLUS) was used in the experiment. For each file system, vibrations generated when using a size 25 file were measured and used to calculate the average vibration acceleration. The differences in vibrations were analyzed using 1-way analysis of variance and the Scheffé post hoc test with a confidence interval of 95%. Results: In the PTG file system, significantly lower vibration acceleration was observed when using a 21-mm file than when using a 31-mm file. In the WOG file system, significantly stronger vibration acceleration was observed when using a 31-mm file than when using 21- or 25-mm files. Regardless of the file length, the WOG group exhibited significantly stronger vibration acceleration than the other 2 experimental groups. Conclusions: In clinical practice, choosing a file with the shortest length possible could help reduce vibrations. Additionally, consideration should be given to vibrations that could be generated when using WOG files with reciprocating motion.

• Journal of the Korean Society for Library and Information Science
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• v.26
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• pp.35-51
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• 1994

This article presents the role of children's librarian in the age of information. Preparing the 21st century, there should have been to identify the humanities of health, independent, creative, and moral fact with educating children in future Korea. Children's library should service all the children to improve the information skill and technology, to creat a whole person with high order intellectual thinking skill for the consumer, the voter and the leader of the next generation. It has been identified that the children's librarian should playas a mediator of literacy and culture of children, a creating counselor of personality, a negotiator of recoginating all knowledge, and a leader of the information skill or communication skill in the children education at the 21st century.

• IMMUNE NETWORK
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• v.10 no.2
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• pp.76-81
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• 2010

Ultraviolet B (UVB) induces multiple inflammatory and carcinogenic reactions. In skin, UVB induces to secrete several kinds of inflammatory cytokines from keratinocytes and also increases angiogenic process via the modulation of vascular endothelial growth factor (VEGF) production. Interleukin-21 (IL-21) is an inflammatory cytokine and produced by activated T cells. The biologic functions of IL-21 have not yet extensively studied. In the present study, we investigate the production of IL-21 from human keratinocyte cell line, HaCaT and its biological effect after exposure to UVB. First, we confirmed the IL-21 production and its receptor expression in HaCaT. And then, the change of IL-21 and VEGF production in HaCaT by UVB irradiation was examined. Not only IL-21 but also VEGF production was enhanced by UVB irradiation. Next, to determine relationship of enhanced production of IL-21 and VEGF, we detected VEGF production after neutralization of IL-21. VEGF production was reduced by IL-21 neutralization, which indicates that the IL-21 is involved in the VEGF production. Taken together, our results suggest that IL-21 and VEGF production is enhanced by UVB irradiation in HaCaT. In addition, it seems that IL-21 plays a role in the angiogenic process in skin via the modulation of VEGF production.

• Journal of Broadcast Engineering
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• v.8 no.4
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• pp.365-380
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• 2003

Since MPEG-21 IPMP has been working on International Standardization activity such as one of DRM systems from 1997, the standardization is recently re-started even though the activity was interrupted. According to the MPEG Brisbane meeting, the CfR of MPEG-21 IPMP will be determined on the next Hawaii meeting, therefore they will announce the CfP. However the CfP announced in MPEG Hawaii meeting but the CfR didn't announce because of unfinished requirement document job. Finally. the proposed techniques will be submitted till June 2004. In this paper, we explained the requirement of standardization based on a broadcasting circumstance and implemented the system of MPEG-21 including the architecture and IPMP systems, then we showed all functionality within the other MPEG-21 elements engines. In case of multimedia stream broadcasting system, it is a real-time processing system, the implemented MEPG-21 Architecture can be shown the use of Digital Item In the MPEG-21 terminal and additional MPEG-21 element engines.

• Journal of Digital Convergence
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• v.13 no.12
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• pp.13-21
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• 2015

Ongoing advances in wireless broadband technologies can affect all of industrial society. As new wireless broadband technologies emerge, they will improve competition between established industries and their current services and produce new industries and new converged services. This paper analyzes the trend of next-generation wireless broadband and suggests ways of activating the industry further. To this end, we analyze the trend for previous wireless broadband industries and find out three influential factors (content, wireless network technology, and service) that will produce the continued growth of wireless broadband. Using these three factors, we propose a network technology-driven growth model. Based on that model, we offer activation plans for next-generation wireless broadband industries. This study thus provides an insightful perspective for next-generation wireless broadband industries by establishing additional useful guidelines for developing wireless broadband industries in the future.

• Genomics & Informatics
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• v.21 no.3
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• pp.38.1-38.8
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• 2023

Non-small cell lung cancer (NSCLC) is an important cause of cancer-associated deaths worldwide. Therefore, the exact molecular mechanisms of NSCLC are unidentified. The present investigation aims to identify the miRNAs with predictive value in NSCLC. The two datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed miRNAs (DEmiRNA) and mRNAs (DEmRNA) were selected from the normalized data. Next, miRNA-mRNA interactions were determined. Then, co-expression network analysis was completed using the WGCNA package in R software. The co-expression network between DEmiRNAs and DEmRNAs was calculated to prioritize the miRNAs. Next, the enrichment analysis was performed for DEmiRNA and DEmRNA. Finally, the drug-gene interaction network was constructed by importing the gene list to dgidb database. A total of 3,033 differentially expressed genes and 58 DEmiRNA were recognized from two datasets. The co-expression network analysis was utilized to build a gene co- expression network. Next, four modules were selected based on the Z_summary score. In the next step, a bipartite miRNA-gene network was constructed and hub miRNAs (let-7a-2-3p, let-7d-5p, let-7b-5p, let-7a-5p, and let-7b-3p) were selected. Finally, a drug-gene network was constructed while SUNITINIB, MEDROXYPROGESTERONE ACETATE, DOFETILIDE, HALOPERIDOL, and CALCITRIOL drugs were recognized as a beneficial drug in NSCLC. The hub miRNAs and repurposed drugs may act a vital role in NSCLC progression and treatment, respectively; however, these results must validate in further clinical and experimental assessments.

• Korean Journal of Animal Reproduction
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• v.25 no.3
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• pp.251-257
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• 2001

This study was carried out to investigate the effect of breed, parity, litter size, lactating period, and estrus interval on sow productivity traits in swine. Data from 492 heads of Landrace, Yorkshire or crossbred sow which were raised at Yonam College of Agriculture from March, 1998 to July, 2000 were analyzed for this study. The total number of pigs born (TN), the number of pigs born alive (NB), and the number of pigs suckled (NS) were greater in the crossbred sows than in the purebred. In TN and NB, the 3rd to 7th parities were greater than other parities, and the 8th parity was the lowest. The number of pigs stillbirthed (NSB) and the number of runt per litter tended to increase with the increase of TN. In addition, statistical analysis showed that parity had significant effect on most of traits. The current TN had highly significant effect on TN, NB and NS of the next parity As current TN increased, TN, NB, and NS of the next parity increased. The current lactating period also affected significantly for TN, NB, and NS of the next parity The sows which had the lactating period of 20∼21 days produced the greatest TN and NB in the next parity. Weaning to estrus interval(WEI) had significant effect on TN, NB, and NSB. Among WEI groups, the WEI group of 7∼13 days was the lowest in TN, NB and NSB.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1976.06a
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• pp.86.2-86
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• 1976

Authors have performed the audiological analysis in accordance with age, sex, site, duration, cause, ear drums, curve pattern, and hearing level taken from 165 patients (Male; 101, Female; 64) with non-perforated ear drums who had complained hearing impairment. The results are as follows. 1. The audiographic pattern has classified into Normal (30 cases, 18.18%), Flat form (46 cases, 20.6%), Ascending form (5 cases, 3%), Mountain form (9 cases, 5.4%), Basin form (7 cases, 4.2%), Total deaf (24 cases, 14.55%) and Others (10 cases, 6%). 2. In age distribution, the highest is in 3rd decade (50 cases, 30.3%), and the next is in 2nd (43 cases, 26%), 4th (27 cases, 16.3%) in order. 3. Male (101 cases) is more than female (64 cases) giving ratio of 1.9 : 1 4. Bilateral involvement is in 58 cases and unilateral is in 77 5. 45 cases (27.3%) in duration of hearing loss is as short as 3 months and the next is overs; 28 cases (16.9%) 6 to 10 years; 21 cases (12. 7%). And in cases of total deaf, nearly all cases is over 10 years. 6. The suspected cause of the hearing loss is unknown (99 cases, 60%) and the next is following head trauma by traffic accidents in 31 cases (18.8 %) and is related to the middle ear diseased in 12. cases (7.3%). Other causes like senile, noise etc. are in few. 7. The most common findings in ear drums is normal in 177 ears (79.4%) and the next is retracted drums in 28 ears (12.6%). 8. The average hearing level is widely distributed from mild to profound hearing loss which was not related to the audigraphic pattern.

• Proceedings of the Zoological Society Korea Conference
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• 1998.10b
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• pp.360-360
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• 1998

C11, a chloride-containing VK3 analog, acts as a mediator of programmed cell death in SK-Hep-1 cell lines, but its molecular mechanisms linked to cell death are not understood. In this study, we investigated the expression of p21 gene and its relationship to apoptosis induced by C11. In SK -hep-1 cells, the addition of C11 resulted in time-dependent growth suppression and DNA fragmentation characteristics of apoptosis. p21 protein was induced during this process, while the protein level of p53 was not changed at the same condition. This apoptotic cell death with p21 induction was also observed in the Hep3B cells lacking functional p53 after treatment of C11. These results suggest that C11-induced apoptosis is associated with up-regulation of p21 protein in p53-independent pathway. Next, in order to confirm whether the p53-independent p21 induction is required for C11-induced apoptosis, we introduced the p21 gene into Hep3B. Overexpression of p21 did not affect the expression of the bcl-2 gene, but DNA fragmentation and PARa cleavage were significantly increased. These data indicate that p21 is involved in C11-induced apoptosis. Although Bcl-2 has been implicated to interfere with an essential signaling molecule involved in the apoptosis pathway, its molecular mechanism and target molecule are poorly understood. To determine the effects of bcl-2 overexpression on apoptosis and to investigate whether BcI-2 interfers with the p53-independent p21 pathway, we transfected the bcl-2 expression vector into SK - Hep-1 cels. Overexpression of Bcl-2 prevented C11-induced apoptosis. Taken together, C11-induced apoptosis is regulated by p52-independent p21 pathway and bcl-2 may inhibit functional activity of p21, therebe may inhibit the C11-induced apoptosis.ptosis.

• Information and Communications Magazine
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• v.21 no.5
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• pp.35-45
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• 2004

국내외 정보통신서비스산업은 끊임없는 기술 진화와 고객 요구수준의 변화 등 산업을 둘러싸고 있는 경영환경이 급변함에 따라 서비스 및 산업의 기존 영역이 붕괴되고 다시 결합하는 과정이 반복되면서 새로운 산업 및 서비스가 창출되는 패러다임의 대 전환기에 처해있다. 이러한 새로운 패러다임의 핵심적인 사례로는 유비쿼터스 네트워킹 및 NGN(Next Generation Network)의 기술진화를 기반으로 한 DMB, 홈 네트워킹, 텔레매틱스와 같은 디지털 컨버전스를 들 수 있다.(중략)