열린충남 30호-[지상포럼]호남고속철도 노선의 합리적 선정방안

이날 세미나에서 이정록교수는 '호남고속철도 노선의 합리적 선정방법'이라는 주제로 논문을 발표하였는데, 서론 부분인 호남고속철도 건설의 특징과 쟁점과 본론 부분인 분기역 선정의 쟁점부분은 생략하고 결론부분인 합리적 노선 선정을 위한 고려사항과 결론부분을 요약하여 전재한다. -이후 생략1. 합리적 노선 선정을 위한 주요 고려사항 2. 결론 및 제

High performance wash-free magnetic bioassays through microfluidically enhanced particle specificity

Magnetic biosensors have emerged as a sensitive and versatile platform for high performance medical diagnostics. These magnetic biosensors require well-tailored magnetic particles as detection probes, which need to give rise to a large and specific biological signal while showing very low nonspecific binding. This is especially important in wash-free bioassay protocols, which do not require removal of particles before measurement, often a necessity in point of care diagnostics. Here we show that magnetic interactions between magnetic particles and magnetized sensors dramatically impact particle transport and magnetic adhesion to the sensor surfaces. We investigate the dynamics of magnetic particles' biomolecular binding and magnetic adhesion to the sensor surface using microfluidic experiments. We elucidate how flow forces can inhibit magnetic adhesion, greatly diminishing or even eliminating nonspecific signals in wash-free magnetic bioassays, and enhancing signal to noise ratios by several orders of magnitude. Our method is useful for selecting and optimizing magnetic particles for a wide range of magnetic sensor platforms

Longitudinal multiplexed measurement of quantitative proteomic signatures in mouse lymphoma models using magneto-nanosensors

Cancer proteomics is the manifestation of relevant biological processes in cancer development. Thus, it reflects the activities of tumor cells, host-tumor interactions, and systemic responses to cancer therapy. To understand the causal effects of tumorigenesis or therapeutic intervention, longitudinal studies are greatly needed. However, most of the conventional mouse experiments are unlikely to accommodate frequent collection of serum samples with a large enough volume for multiple protein assays towards single-object analysis. Here, we present a technique based on magneto-nanosensors to longitudinally monitor the protein profiles in individual mice of lymphoma models using a small volume of a sample for multiplex assays. Methods: Drug-sensitive and -resistant cancer cell lines were used to develop the mouse models that render different outcomes upon the drug treatment. Two groups of mice were inoculated with each cell line, and treated with either cyclophosphamide or vehicle solution. Serum samples taken longitudinally from each mouse in the groups were measured with 6-plex magneto-nanosensor cytokine assays. To find the origin of IL-6, experiments were performed using IL-6 knock-out mice. Results: The differences in serum IL-6 and GCSF levels between the drug-treated and untreated groups were revealed by the magneto-nanosensor measurement on individual mice. Using the multiplex assays and mouse models, we found that IL-6 is secreted by the host in the presence of tumor cells upon the drug treatment. Conclusion: The multiplex magneto-nanosensor assays enable longitudinal proteomic studies on mouse tumor models to understand tumor development and therapy mechanisms more precisely within a single biological object. © Ivyspring International Publisher

Flow Homogenization Enables a Massively Parallel Fluidic Design for High-Throughput and Multiplexed Cell Isolation

Microfluidic devices are widely used for applications such as cell isolation. Currently, the most common method to improve throughput for microfluidic devices involves fabrication of multiple, identical channels in parallel. However, this “numbering up” only occurs in one dimension, thereby limiting gains in volumetric throughput. In contrast, macrofluidic devices permit high volumetric flow rates but lack the finer control of microfluidics. Here, it is demonstrated how a micropore array design enables flow homogenization across a magnetic cell capture device, thus creating a massively parallel series of microscale flow channels with consistent fluidic and magnetic properties, regardless of spatial location. This design enables scaling in two dimensions, allowing flow rates exceeding 100 mL h−1 while maintaining >90% capture efficiencies of spiked lung cancer cells from blood in a simulated circulating tumor cell system. Additionally, this design facilitates modularity in operation, which is demonstrated by combining two different devices in tandem for multiplexed cell separation in a single pass with no additional cell losses from processing. © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei

Portable, one-step, and rapid GMR biosensor platform with smartphone interface

Quantitative immunoassay tests in clinical laboratories require trained technicians, take hours to complete with multiple steps, and the instruments used are generally immobile-patient samples have to be sent in to the labs for analysis. This prevents quantitative immunoassay tests to be performed outside laboratory settings. A portable, quantitative immunoassay device will be valuable in rural and resource limited areas, where access to healthcare is scarce or far away. We have invented Eigen Diagnosis Platform (EDP), a portable quantitative immunoassay platform based on Giant Magnetoresistance (GMR) biosensor technology. The platform does not require a trained technician to operate, and only requires one-step user involvement. It displays quantitative results in less than 15 min after sample insertion, and each test costs less than US$4. The GMR biosensor employed in EDP is capable of detecting multiple biomarkers in one test, enabling a wide array of immune diagnostics to be performed simultaneously. In this paper, we describe the design of EDP, and demonstrate its capability. Multiplexed assay of human immunoglobulin G and M (IgG and IgM) antibodies with EDP achieves sensitivities down to 0.07 and 033 nanomolar, respectively. The platform will allow lab testing to be performed in remote areas, and open up applications of immunoassay testing in other non-clinical settings, such as home, school, and office. (C) 2016 Elsevier B.V. All rights reserved

Magneto-nanosensor platform for probing low-affinity protein-protein interactions and identification of a low-affinity PD-L1/PD-L2 interaction

Substantial efforts have been made to understand the interactions between immune checkpoint receptors and their ligands targeted in immunotherapies against cancer. To carefully characterize the complete network of interactions involved and the binding affinities between their extracellular domains, an improved kinetic assay is needed to overcome limitations with surface plasmon resonance (SPR). Here, we present a magneto-nanosensor platform integrated with a microfluidic chip that allows measurement of dissociation constants in the micromolar-range. High-density conjugation of magnetic nanoparticles with prey proteins allows multivalent receptor interactions with sensor-immobilized bait proteins, more closely mimicking natural-receptor clustering on cells. The platform has advantages over traditional SPR in terms of insensitivity of signal responses to pH and salinity, less consumption of proteins and better sensitivities. Using this platform, we characterized the binding affinities of the PD-1-PD-L1/PD-L2 co-inhibitory receptor system, and discovered an unexpected interaction between the two known PD-1 ligands, PD-L1 and PD-L2

Magnetoresistive biosensors with on-chip pulsed excitation and magnetic correlated double sampling

Giant magnetoresistive (GMR) sensors have been shown to be among the most sensitive biosensors reported. While high-density and scalable sensor arrays are desirable for achieving multiplex detection, scalability remains challenging because of long data acquisition time using conventional readout methods. In this paper, we present a scalable magnetoresistive biosensor array with an on-chip magnetic field generator and a high-speed data acquisition method. The on-chip field generators enable magnetic correlated double sampling (MCDS) and global chopper stabilization to suppress 1/f noise and offset. A measurement with the proposed system takes only 20 ms, approximately 50x faster than conventional frequency domain analysis. A corresponding time domain temperature correction technique is also presented and shown to be able to remove temperature dependence from the measured signal without extra measurements or reference sensors. Measurements demonstrate detection of magnetic nanoparticles (MNPs) at a signal level as low as 6.92 ppm. The small form factor enables the proposed platform to be portable as well as having high sensitivity and rapid readout, desirable features for next generation diagnostic systems, especially in point-of-care (POC) settings

Multiplex giant magnetoresistive biosensor microarrays identify interferon-associated autoantibodies in systemic lupus erythematosus

High titer, class-switched autoantibodies are a hallmark of systemic lupus erythematosus (SLE). Dysregulation of the interferon (IFN) pathway is observed in individuals with active SLE, although the association of specific autoantibodies with chemokine score, a combined measurement of three IFN-regulated chemokines, is not known. To identify autoantibodies associated with chemokine score, we developed giant magnetoresistive (GMR) biosensor microarrays, which allow the parallel measurement of multiple serum antibodies to autoantigens and peptides. We used the microarrays to analyze serum samples from SLE patients and found individuals with high chemokine scores had significantly greater reactivity to 13 autoantigens than individuals with low chemokine scores. Our findings demonstrate that multiple autoantibodies, including antibodies to U1-70K and modified histone H2B tails, are associated with IFN dysregulation in SLE. Further, they show the microarrays are capable of identifying autoantibodies associated with relevant clinical manifestations of SLE, with potential for use as biomarkers in clinical practice

Green Tourism and Tourism Village Building Strategy : Concept and Practices

대중관광의 활성화로 관광활동이 경제부분의 중요한 요소로 등장하고 있고, 1980년 이후에는 그린투어리즘이 새로운 관광유형인 대안관광으로 기능하고 있다. 대안관광과 관련하여 관광개발에 따른 환경적·경제적·사회적·문화적 영향을 최소화하고, 지역주민의 일상적인 생활에 그대로 반영되어 지역민과의 일체성을 강조하는 친환경적 관광전략이 관광마을만들기이다. 관광활동을 매개로 지역활성화를 도모하는 지역운동 차원의 관광마을 만들기 전략은 일본과 우리나라의 일부 지자체에서 성공적으로 전개되고 있다. 특히 우리나라의 화천군 토고미 마을과 남해군의 다랭이 마을은 대표적인 사례에 해당한다. 따라서 고유한 문화와 전통, 그리고 청정의 농촌환경과 아름다운 농촌경관을 보유한 전남지역은 관광마을 만들기를 지역관과의 진홍전략으로 수용할 필요가 있다. With the rapid growth of mass-tourism, tourism and leisure activities are growing significant components of economic sector, and alternative tourisms are functioned as new type of tourism since 1980. In addition, rural areas have long played as important role in tourism and leisure within the developed world. Among several travel and tourism activities, tourism village building strategy is appeared as the natural oriented tourism strategy related to alternative tourism, and it emphasis on some factors such as the sense of unity with community citizens, daily life of community, and environmental and cultural aspects of community as life space. Particularly it consider the useful tourism promotion strategy by means of local and regional development. In recent, tourism village building strategy contribute important roles for the promotion of local tourism in particular rural areas, and some of local villages of Korea have adopted this strategy in the dimension of population movement in order to advertise their tourism market and pull many tourists into their village. The typical successful cases are togomi-mawool(village) of Hwachon county of Gwangwon province and Darangi-mawool(village) of Namhae county of Geongnam province. Therefore, Chonnam province also have to concern about new community movement for tourism village building, and to adopt about several strategies used the unique rural landscapes, physical and cultural resources, and rural lifes

High-Resolution Analysis of Antibodies to Post-Translational Modifications Using Peptide Nanosensor Microarrays

Autoantibodies are a hallmark of autoimmune diseases such as lupus and have the potential to be used as biomarkers for diverse diseases, including immunodeficiency, infectious disease, and cancer. More precise detection of antibodies to specific targets is needed to improve diagnosis of such diseases. Here, we report the development of reusable peptide microarrays, based on giant magnetoresistive (GMR) nanosensors optimized for sensitively detecting magnetic nanoparticle labels, for the detection of antibodies with a resolution of a single post-translationally modified amino acid. We have also developed a chemical regeneration scheme to perform multiplex assays with a high level of reproducibility, resulting in greatly reduced experimental costs. In addition, we show that peptides synthesized directly on the nanosensors are approximately two times more sensitive than directly spotted peptides. Reusable peptide nanosensor microarrays enable precise detection of autoantibodies with high resolution and sensitivity and show promise for investigating antibody-mediated immune responses to autoantigens, vaccines, and pathogen-derived antigens as well as other fundamental peptide protein interactions