• Title/Summary/Keyword: emerging

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Inhibition of HBV replication and gene expression in vitro and in vivo with a single AAV vector delivering two shRNA molecules

  • Li, Zhi;He, Ming-Liang;Yao, Hong;Dong, Qing-Ming;Chen, Yang-Chao;Chan, Chu-Yan;Zheng, Bo-Jian;Yuen, Kwok-Yung;Peng, Ying;Sun, Qiang;Yang, Xiao;Lin, Marie C.;Sung, Joseph J.Y.;Kung, Hsiang-Fu
    • BMB Reports
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    • v.42 no.1
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    • pp.59-64
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    • 2009
  • Hepatitis B virus (HBV) infection is highly prevalent worldwide. The major challenge for current antiviral treatment is the elevated drug resistance that occurs via rapid viral mutagenesis. In this study, we developed AAV vectors to simultaneously deliver two or three shRNAs targeting different HBV-related genes. These vectors showed markedly better antiviral effects than ones that delivered a single shRNA in vitro. A dual shRNA expression vector (AAV-157i/1694i), which simultaneously expressed two shRNAs targeted the S and X genes of HBV, reduced HBsAg, HBeAg and HBV DNA levels by $87{\pm}4$, $80.3{\pm}2.6$ and $86.2{\pm}7%$ respectively, eight days post-transduction. In a mouse model of prophylactic treatment, HBsAg and HBeAg were reduced to undetectable levels and the serum HBV DNA level was reduced by at least 100 fold. These results indicate that AAV-157i/1694i generates potent anti-HBV effects and that the strategy of constructing multi-shRNA expression vectors may lead to enhanced anti-HBV efficacy and overcome the evading mechanism of the virus and thus the development of drug resistance.

Research of Emerging Process on Scientific Creative Products: Case Study of Self-Organization Process on Emerging of objective knowledge from Subjective Experience of Scientists (과학 분야 창의적 산물 발현과정 연구: 과학자의 주관적 경험이 객관적 지식으로 발현하는 자기조직화 과정의 사례 분석)

  • Kang, Jungha;Cho, Sunhee;Kim, Mijin
    • Journal of Gifted/Talented Education
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    • v.24 no.1
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    • pp.113-147
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    • 2014
  • This study is a case study of the process of emerging for creative products to lead world science and technology. The aim of the study is to understand the emerging process of scientific creative products, and is to provide the direction of gifted education that discovers and trains globally competitive science talents through this. To discuss the emerging process of creative products, this study has academically discussed the creativity of the complexity of dealing with theory of evolution, the real life settings, and self-organization of experience etc., and has methodologically adopted the qualitative research method through a case study to look at the structures and processes. Data collection has been formed through a discussion with 12 Korean scientists who have created selected creative products, greatly contributed for the world science and technology(12 areas). The analysis has been carried out by the latter part positivist methods. As a result, the emerging process of creative products in the field of science and technology were separated into four steps: (1)the foundation stage of knowledge, (2)the exploration stage of knowledge, (3)the construction stage of knowledge, and (4)the emerging stage of knowledge. Each stage has been revealed growing up through the macro-system and the self-organization of each micro-systems.

Investigation of dust particle removal efficiency of self-priming venturi scrubber using computational fluid dynamics

  • Ahmed, Sarim;Mohsin, Hassan;Qureshi, Kamran;Shah, Ajmal;Siddique, Waseem;Waheed, Khalid;Irfan, Naseem;Ahmad, Masroor;Farooq, Amjad
    • Nuclear Engineering and Technology
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    • v.50 no.5
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    • pp.665-672
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    • 2018
  • A venturi scrubber is an important element of Filtered Containment Venting System (FCVS) for the removal of aerosols in contaminated air. The present work involves computational fluid dynamics (CFD) study of dust particle removal efficiency of a venturi scrubber operating in self-priming mode using ANSYS CFX. Titanium oxide ($TiO_2$) particles having sizes of 1 micron have been taken as dust particles. CFD methodology to simulate the venturi scrubber has been first developed. The cascade atomization and breakup (CAB) model has been used to predict deformation of water droplets, whereas the Eulerian-Lagrangian approach has been used to handle multiphase flow involving air, dust, and water. The developed methodology has been applied to simulate venturi scrubber geometry taken from the literature. Dust particle removal efficiency has been calculated for forced feed operation of venturi scrubber and found to be in good agreement with the results available in the literature. In the second part, venturi scrubber along with a tank has been modeled in CFX, and transient simulations have been performed to study self-priming phenomenon. Self-priming has been observed by plotting the velocity vector fields of water. Suction of water in the venturi scrubber occurred due to the difference between static pressure in the venturi scrubber and the hydrostatic pressure of water inside the tank. Dust particle removal efficiency has been calculated for inlet air velocities of 1 m/s and 3 m/s. It has been observed that removal efficiency is higher in case of higher inlet air velocity.

Comparison of Digital PCR and Quantitative PCR with Various SARS-CoV-2 Primer-Probe Sets

  • Park, Changwoo;Lee, Jina;Hassan, Zohaib ul;Ku, Keun Bon;Kim, Seong-Jun;Kim, Hong Gi;Park, Edmond Changkyun;Park, Gun-Soo;Park, Daeui;Baek, Seung-Hwa;Park, Dongju;Lee, Jihye;Jeon, Sangeun;Kim, Seungtaek;Lee, Chang-Seop;Yoo, Hee Min;Kim, Seil
    • Journal of Microbiology and Biotechnology
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    • v.31 no.3
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    • pp.358-367
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    • 2021
  • The World Health Organization (WHO) has declared the coronavirus disease 2019 (COVID-19) as an international health emergency. Current diagnostic tests are based on the reverse transcription-quantitative polymerase chain reaction (RT-qPCR) method, which is the gold standard test that involves the amplification of viral RNA. However, the RT-qPCR assay has limitations in terms of sensitivity and quantification. In this study, we tested both qPCR and droplet digital PCR (ddPCR) to detect low amounts of viral RNA. The cycle threshold (CT) of the viral RNA by RT-PCR significantly varied according to the sequences of the primer and probe sets with in vitro transcript (IVT) RNA or viral RNA as templates, whereas the copy number of the viral RNA by ddPCR was effectively quantified with IVT RNA, cultured viral RNA, and RNA from clinical samples. Furthermore, the clinical samples were assayed via both methods, and the sensitivity of the ddPCR was determined to be equal to or more than that of the RT-qPCR. However, the ddPCR assay is more suitable for determining the copy number of reference materials. These findings suggest that the qPCR assay with the ddPCR defined reference materials could be used as a highly sensitive and compatible diagnostic method for viral RNA detection.

Conceptual Framework of Reverse Retail Internationalization: From the Perspective of Retail Innovation and Retail Format

  • Cho, Myung-Rae;Mukoyama, Masao
    • Journal of Distribution Science
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    • v.14 no.11
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    • pp.5-17
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    • 2016
  • Purpose - The purpose of this study is to establish an conceptual framework to explain the mechanism of internationalization behavior being used by recently established retailer in emerging countries. Research design, data, and methodology - The existing research on retail internationalization has focused on global retailers located in advanced countries which have expanded their business to emerging countries. That is, "internationalization from top to bottom". However, recent years have seen a reversal in this trend, resulting in the emergence of "internationalization from bottom to top" by retailers based in emerging economies. In order to explore this reversal, this study attempts to develop an conceptual framework based on the theories of "innovation" and "retail format". Results - This study found an conceptual framework which was adopted both a concept of "formula" derived from the theory of retail format and a concept of "production and process innovation" derived from the theory of innovation as a core concept. Conclusions - The conceptual framework provided an understanding of how retailers in emerging countries have gained a competitive advantage over retail companies based in countries with advanced economies. It suggested that innovation that gave these companies a competitive edge was caused by competitive interaction which allowed them to expand to oversea markets.

Investment and Debt ratio of ICT firms (ICT 기업의 부채수준이 투자활동에 미치는 영향)

  • Chon, Mi-Lim
    • Journal of the Korea Convergence Society
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    • v.6 no.1
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    • pp.103-108
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    • 2015
  • This paper investigate the determinants of investment for a cross-section of firms in emerging market. I examine three factors expected to affect investment: debt ratio, growth rate, and industry. I find that debt ratio and ICT firms are positively associated with investment in emerging market. I also find that ICT firms with high debt ratio have higher net capital expenditures. While the growth rate is unrelated to net capital expenditures. Unlike the evidence from the developed markets, debt ratio has significant and positive impact on investment (net capital expenditures) in the emerging market.

A Study on the Identifying Emerging Defense Technology using S&T Text Mining (S&T Text Mining을 이용한 국방 유망기술 식별에 관한 연구)

  • Lee, Tae-Bong;Lee, Choon-Joo
    • Journal of the military operations research society of Korea
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    • v.36 no.1
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    • pp.39-49
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    • 2010
  • This paper tries to identify emerging defense technology using S&T Text Mining. As a national agenda, there has been much effort to build S&T information systems including NTIS and DTiMS that enable researchers, policy makers, or field users to analyze technological changes and promote the best policy practices for efficient workflow, knowledge sharing, strategy development, or institutional competitiveness. In this paper, the S&T Text Mining application to unmanned combat technology using INSPEC DB is empirically illustrated and shows that it is a feasible approach to identify emerging defense technology as well as the structure of knowledge network of the future technology candidates.