• Title/Summary/Keyword: synthetic approaches

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Synthetic Approaches to Benzophenanthridines

  • Gang, Seong-Gyoung;Le NguyenThanh;Cho, Won-Jea
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.355.2-355.2
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    • 2002
  • Benzo[c] phenanthridine alkaloids occurring in the Fumariaceae, Papaveraceae, and Rutaceae. posses numerous pharmacological activities, such as antitumor. antimicrobal and antifungal activities. Thus, they have attracted much interests of chemists and as the result, several total syntheses of these heterocycle structure were accomplished. Among that, procedures which involve 3-arylisoquinoline intermediates are useful methods and these synthons could be also applied to the preparation of other alkaloids. (omitted)

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A Comparative Study of Various Approaches of Seismic Ground Response Analyses by Using a Round Robin Test Methodology (Round Robin Test 기법을 통한 다양한 지반응답해석 접근법 비교 연구)

  • Kim, Jin-Man;Park, Yo-Hwan;Kim, Ki-Seog;Park, Du-Hee;Sun, Chang-Guk;Kim, Sung-Ryul
    • Proceedings of the Korean Geotechical Society Conference
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    • 2007.09a
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    • pp.259-265
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    • 2007
  • The technical committee of Soil Dynamics and Geotechnical Earthquake Engineering of Korean Geotechnical Socity has conducted Round Robin Test(RRT) on seismic ground response analyses in 2007. Total 14 participating teams were given exact same soil information of three sites and three input ground motions including two recorded ground motions and one synthetic ground motion. Each team selected its own analysis method and approaches to perform ground response analyses. There were equivalent linear, nonlinear total stress, and nonlinear effective stress approaches, which could be selected. The results from RRT were systematically analyzed and dispersion and variation due to analysis methods, input ground motions, shear velocity profiles, shear modulus reduction curves, damping curves, and other input data are reported by the companion papers.

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Review of the Synthetic Rock Mass Approach (합성암반체 접근법에 대한 고찰)

  • Park, Chul-Whan;Synn, Joong-Ho;Park, Eui-Seop
    • Tunnel and Underground Space
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    • v.17 no.6
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    • pp.438-447
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    • 2007
  • This technical report is to introduce the research on SRM (Synthetic Rock Mass) which was presented in 2007 ISRM Congress at Lisbon by Prof, Fairhurst who speak with emphasis on its importance and potential in rock engineering. The Synthetic Rock Mass approach to jointed rock mass characterization (Pierce et al. 2007) is reviewed relative to existing empirical approaches and current understanding of jointed rock mass behaviour. The review illustrates how the key factors affecting the mechanical behaviour of jointed rock masses may be considered and demonstrates that the SRM approach constitutes a significant step forward in this field. This technique, based on two well-established methods, Bonded Particle Modelling in PFC-3D (Potyondy and Cundall, 2004) and Discrete Fracture Network simulation, employs a new sliding joint model that allows for large rock volumes containing thousands of pre-existing joints to be subjected to any non-trivial stress path. Output from SRM testing includes rock mass brittleness and strength, evolution of the full compliance matrix and primary fragmentation.

Mitochondrial OXPHOS genes provides insights into genetics basis of hypoxia adaptation in anchialine cave shrimps

  • Guo, Huayun;Yang, Hao;Tao, Yitao;Tang, Dan;Wu, Qiong;Wang, Zhengfei;Tang, Boping
    • Genes and Genomics
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    • v.40 no.11
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    • pp.1169-1180
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    • 2018
  • Cave shrimps from the genera Typhlatya, Stygiocaris and Typhlopatsa (TST complex) comprises twenty cave-adapted taxa, which mainly occur in the anchialine environment. Anchialine habitats may undergo drastic environmental fluctuations, including spatial and temporal changes in salinity, temperature, and dissolved oxygen content. Previous studies of crustaceans from anchialine caves suggest that they have possessed morphological, behavioral, and physiological adaptations to cope with the extreme conditions, similar to other cave-dwelling crustaceans. However, the genetic basis has not been thoroughly explored in crustaceans from anchialine habitats, which can experience hypoxic regimes. To test whether the TST shrimp-complex hypoxia adaptations matched adaptive evolution of mitochondrial OXPHOS genes. The 13 OXPHOS genes from mitochondrial genomes of 98 shrimps and 1 outgroup were examined. For each of these genes was investigated and compared to orthologous sequences using both gene (i.e. branch-site and Datamonkey) and protein (i.e. TreeSAAP) level approaches. Positive selection was detected in 11 of the 13 candidate genes, and the radical amino acid changes sites scattered throughout the entire TST complex phylogeny. Additionally, a series of parallel/convergent amino acid substitutions were identified in mitochondrial OXPHOS genes of TST complex shrimps, which reflect functional convergence or similar genetic mechanisms of cave adaptation. The extensive occurrence of positive selection is suggestive of their essential role in adaptation to hypoxic anchialine environment, and further implying that TST complex shrimps might have acquired a finely capacity for energy metabolism. These results provided some new insights into the genetic basis of anchialine hypoxia adaptation.

A Study of the Aging Properties of the Common Synthetic Resin Adhesives for Paper Conservation Purposes (시판용 접착제의 지류보존처리 적합성 판단을 위한 열화 특성 연구)

  • Sung, Yeonsim;Youm, Inkyung
    • Journal of Conservation Science
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    • v.28 no.4
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    • pp.387-394
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    • 2012
  • Most of the libraries and archives that lacks conservation lab facilities, frequently apply common synthetic resin adhesives such as PVAc group(Pa), acrylic group(Ac) and PVP group(Pv) on simple repairs. The archival quality synthetic adhesive(Pa-1) that is used at the National Library of Korea and the common synthetic resin adhesives were selected for the experiments. Accelerated aging test was applied on the adhesive samples and change of the pH and chromaticity were measured for one month. As the result of the pH mesurments, Pa-1 and Ac-2 were at the acceptable pH range. As the result of the chromaticity mesurments, degree of yellowing(${\Delta}b^*$) showed smaller change to greater change in the following order; Pa-1

Essential Computer Vision Methods for Maximal Visual Quality of Experience on Augmented Reality

  • Heo, Suwoong;Song, Hyewon;Kim, Jinwoo;Nguyen, Anh-Duc;Lee, Sanghoon
    • Journal of International Society for Simulation Surgery
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    • v.3 no.2
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    • pp.39-45
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    • 2016
  • The augmented reality is the environment which consists of real-world view and information drawn by computer. Since the image which user can see through augmented reality device is a synthetic image composed by real-view and virtual image, it is important to make the virtual image generated by computer well harmonized with real-view image. In this paper, we present reviews of several works about computer vision and graphics methods which give user realistic augmented reality experience. To generate visually harmonized synthetic image which consists of a real and a virtual image, 3D geometry and environmental information such as lighting or material surface reflectivity should be known by the computer. There are lots of computer vision methods which aim to estimate those. We introduce some of the approaches related to acquiring geometric information, lighting environment and material surface properties using monocular or multi-view images. We expect that this paper gives reader's intuition of the computer vision methods for providing a realistic augmented reality experience.

Statistical disclosure control for public microdata: present and future (마이크로데이터 공표를 위한 통계적 노출제어 방법론 고찰)

  • Park, Min-Jeong;Kim, Hang J.
    • The Korean Journal of Applied Statistics
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    • v.29 no.6
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    • pp.1041-1059
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    • 2016
  • The increasing demand from researchers and policy makers for microdata has also increased related privacy and security concerns. During the past two decades, a large volume of literature on statistical disclosure control (SDC) has been published in international journals. This review paper introduces relatively recent SDC approaches to the communities of Korean statisticians and statistical agencies. In addition to the traditional masking techniques (such as microaggregation and noise addition), we introduce an online analytic system, differential privacy, and synthetic data. For each approach, the application example (with pros and cons, as well as methodology) is highlighted, so that the paper can assist statical agencies that seek a practical SDC approach.

Orbital wall restoring surgery with primary orbital wall fragments in blowout fracture

  • Kang, Dong Hee
    • Archives of Craniofacial Surgery
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    • v.20 no.6
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    • pp.347-353
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    • 2019
  • Most orbital surgeons believe that it's difficult to restore the primary orbital wall to its previous position and that the orbital wall is so thin that cannot be firmly its primary position. Therefore, orbital wall fractures generally have been reconstructed by replacing the bony defect with a synthetic implant. Although synthetic implants have sufficient strength to maintain their shape and position in the orbital cavity, replacement surgery has some drawbacks due to the residual permanent implants. In previous studies, the author has reported an orbital wall restoring technique in which the primary orbital wall fragment was restored to its prior position through a combination of the transorbital and transantral approaches. Simple straight and curved elevators were introduced transnasally to restore the orbital wall and to maintain temporary extraorbital support in the maxillary and ethmoid sinus. A transconjunctival approach provided sufficient space for implant insertion, while the transnasal approach enabled restoration of the herniated soft tissue back into the orbit. Fracture defect was reduced by restoring the primary orbital wall fragment to its primary position, making it possible to use relatively small size implant, furthermore, extraorbital support from both sinuses decreased the incidence of implant displacement. The author could recreate a natural shape of the orbit with the patient's own orbital bone fragments with this dual approach and effectively restored the orbital volume and shape. This procedure has the advantages for retrieving the orbital contents and restoring the primary orbital wall to its prior position.

Microbial linguistics: perspectives and applications of microbial cell-to-cell communication

  • Mitchell, Robert J.;Lee, Sung-Kuk;Kim, Tae-Sung;Ghim, Cheol-Min
    • BMB Reports
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    • v.44 no.1
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    • pp.1-10
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    • 2011
  • Inter-cellular communication via diffusible small molecules is a defining character not only of multicellular forms of life but also of single-celled organisms. A large number of bacterial genes are regulated by the change of chemical milieu mediated by the local population density of its own species or others. The cell density-dependent "autoinducer" molecules regulate the expression of those genes involved in genetic competence, biofilm formation and persistence, virulence, sporulation, bioluminescence, antibiotic production, and many others. Recent innovations in recombinant DNA technology and micro-/nano-fluidics systems render the genetic circuitry responsible for cell-to-cell communication feasible to and malleable via synthetic biological approaches. Here we review the current understanding of the molecular biology of bacterial intercellular communication and the novel experimental protocols and platforms used to investigate this phenomenon. A particular emphasis is given to the genetic regulatory circuits that provide the standard building blocks which constitute the syntax of the biochemical communication network. Thus, this review gives focus to the engineering principles necessary for rewiring bacterial chemo-communication for various applications, ranging from population-level gene expression control to the study of host-pathogen interactions.

Synthetic approaches toward [18F]Fluoromisonidazole as a hypoxia imaging maker

  • Kwon, Young-Do;Lim, Seok Tae;Jeong, Hwan-Jeong;Sohn, Myung-Hee;Kim, Hee-Kwon
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.1 no.1
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    • pp.9-14
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    • 2015
  • Hypoxia has been shown in many tumors because of a reduced oxygen condition. A useful approach to detect hypoxia is to use molecular imaging. Positron emission tomography (PET), one of the biomedical molecular imaging tools, is the most common non-invasive technique for providing information about physiological and biological events such as diseases. In order to use the PET technique for healthcare, promising molecular probes such as PET tracers required. [$^{18}F$]Fluoromisonidazole ([$^{18}F$]FMISO) is the most widely used in PET tracers for hypoxia. In this review, major developments of the synthetic method of [$^{18}F$]FMISO are discussed.