• Title/Summary/Keyword: Flow Detection

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Live Cell Detection of Monoclonal Antibody Light and Heavy Chain mRNAs using Molecular Beacons (분자 비컨을 이용한 살아 있는 세포에서 단일클론항체 경쇄와 중쇄 mRNA 검출에 의한 세포주 선별방법)

  • Jeong, Seunga;Rhee, Won Jong
    • KSBB Journal
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    • v.31 no.1
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    • pp.33-39
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    • 2016
  • Developing the method for the selection of animal cell line producing therapeutic monoclonal antibody (mAb) is invaluable as its market is rapidly growing. Although the quality of produced mAb is as important as quantity, however there is no method developed for the selective screening of cell lines on the basis of both quantity and quality. From recent reports, the ratio of light and heavy chain mRNAs of mAb in the cell is a key parameter for the indication of product quality. Therefore, it is obvious that developing the novel method that can detect both light and heavy chain mRNAs in single live cell will provide unprecedented opportunities in bio-industry. Here, we have constructed oligonucleotide probes, molecular beacons for the detection of light or heavy chain mRNAs, respectively, in the live cells producing mAbs. Both beacons showed increased fluorescent intensity after transient transfection of plasmid expressing mAbs analyzed by fluorometer. Flow cytometric analysis clearly demonstrated that both molecular beacons can simultaneously detect the expression of light and heavy chain mRNAs of mAb in the same cell. The technique described in the thesis provides the new direction and concept for developing the method for the smart selection of cell lines producing recombinant proteins including therapeutic mAbs.

Simultaneous Determination of Tar Color Additives in Cold Syrups by Ion Pair-high Performance Liquid Chromatography (이온쌍-고성능 액체크로마토그래피에 의한 감기약 시럽에서 타르색소 첨가물의 동시분석)

  • Jin, Jing-Yu;Huang, Hu;Lee, Beom-Gyu;Lee, Won-Jae
    • KSBB Journal
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    • v.25 no.5
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    • pp.459-465
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    • 2010
  • A simple and efficient analytical method for the simultaneous determination of seven tar color additives was developed using ion pair high performance liquid chromatography. The conditions for HPLC analysis were as follows: column, ${\mu}$-Bondapak C18 (10 ${\mu}m$, 300 ${\times}$ 3.9 mm i.d.); gradient mobile phase, 0.025 mol/L ammonium acetate (containing 0.01 mol/L tetrabutylammonium bromide)-acetonitrile-methanol (65:25:10) as a mobile for fraction A and 0.025 mol/L ammonium acetate (containing 0.01 mol/L tetrabutylammonium bromide)-acetonitrilemethanol (40:50:10) as a mobile for fraction B; flow rate, 1.0 mL/ min; detection wavelength, 254/520/620 nm. We could attain to the detection limits as 0.01~0.05 ${\mu}$g/mL (254 nm) and 0.005~0.01 ${\mu}$g/mL (520 nm) for six red tar color additives, and 0.05 ${\mu}$g/mL (254 nm) and 0.002 ${\mu}$g/mL (620 nm) for Fast green FCF. This analytical method was applicable to determine the tar color additives contained in several commercial cold syrups.

An Experimental Study on Multi-Fault Detection and Diagnosis Analysis of HVAC System (HVAC 시스템의 중복고장 검출을 위한 실험적 연구)

  • Cho Sung-Hwan;Hong Young-Ju;Yang Hooncheul;Ahn Byung-Cheon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.10
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    • pp.932-941
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    • 2004
  • The objective of this study is to detect the multi-fault of HVAC system using a new pattern classification technique. To classify the effect of single-fault in determining the pattern, supply air temperature, OA-damper, supply fan, and air flowrate were chosen as experimental parameters. The combination of supply temperature, flow rate, supply fan and OA-damper were chosen as multi-fault conditions. Three kinds of patterns were introduced in the analysis of multi-fault problem. To solve multi-fault problem, the new pattern classification technique using residual ratio analysis was introduced to detect the multi-fault as well as single-fault. The residual ratio could diagnose single-fault or multi-fault into several patterns.

Fundamental approach to development of plastic scintillator system for in situ groundwater beta monitoring

  • Lee, UkJae;Choi, Woo Nyun;Bae, Jun Woo;Kim, Hee Reyoung
    • Nuclear Engineering and Technology
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    • v.51 no.7
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    • pp.1828-1834
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    • 2019
  • The performance of a plastic scintillator for use in an in situ measurement system was analyzed using simulation and experimental methods. The experimental results of four major pure beta-emitting radionuclides, namely $^3H$, $^{14}C$, $^{32}P$, and $^{90}Sr/^{90}Y$, were compared with those obtained using a Monte Carlo N-particle (MCNP) code simulation. The MCNP simulation and experimental results demonstrated good agreement for $^{32}P$ and $^{90}Sr/^{90}Y$, with a relative difference of 1.95% and 0.43% between experimental and simulation efficiencies for $^{32}P$ and $^{90}Sr/^{90}Y$, respectively. However, owing to the short range of beta particles in water, the efficiency for $^{14}C$ was extremely low, and $^3H$ could not be detected. To directly measure the low-energy beta radionuclides considering their short range, a system where the source could flow directly to the scintillator was developed. The optimal thickness of the plastic scintillator was determined based on the suggested diameter. Results showed that the detection efficiency decreases with an increase in the depth of the water. The detection efficiency decreased drastically to approximately 10 cm, and the tendency was gradually constant.

A study on the development of the fin-tube heat exchanger pollution ratio evaluation algorithm using Image Processing and Affine Transformation (영상처리 및 어파인변환을 이용한 핀튜브 열교환기 오염율 평가 알고리즘 개발에 관한 연구)

  • Park, Sungmin;Jung, Myungin;Whang, Kwangil;Cho, Gyeongrae
    • Journal of the Korean Society of Visualization
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    • v.20 no.1
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    • pp.11-17
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    • 2022
  • Among the various factors that cause the performance decrease of heat exchangers used in many industries, flow path blocking is one of the important and serious factor. In order to solve this problem, proper maintenance and management of the heat exchanger is important and emphasized. In this study, we developed and algorithm that can quantitatively determine and diagnose the normal and blocked areas of fin-tube heat exchanger using pattern analysis, Gaussian Edge Detection, Image Processing and Affine Transformation techniques. The developed algorithms was applied to the actual heat exchanger and the performance was evaluated by comparing with the manual results. From these results, it was proved that the developed algorithm is effective in evaluating the pollution ratio of the fin-tube heat exchanger.

Calnexin as a dual-role biomarker: antibody-based diagnosis and therapeutic targeting in lung cancer

  • Soyeon Lim;Youngeun Ha;Boram Lee;Junho Shin;Taiyoun Rhim
    • BMB Reports
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    • v.57 no.3
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    • pp.155-160
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    • 2024
  • Lung cancer carries one of the highest mortality rates among all cancers. It is often diagnosed at more advanced stages with limited treatment options compared to other malignancies. This study focuses on calnexin as a potential biomarker for diagnosis and treatment of lung cancer. Calnexin, a molecular chaperone integral to N-linked glycoprotein synthesis, has shown some associations with cancer. However, targeted therapeutic or diagnostic methods using calnexin have been proposed. Through 1D-LCMSMS, we identified calnexin as a biomarker for lung cancer and substantiated its expression in human lung cancer cell membranes using Western blotting, flow cytometry, and immunocytochemistry. Anti-calnexin antibodies exhibited complement-dependent cytotoxicity to lung cancer cell lines, resulting in a notable reduction in tumor growth in a subcutaneous xenograft model. Additionally, we verified the feasibility of labeling tumors through in vivo imaging using antibodies against calnexin. Furthermore, exosomal detection of calnexin suggested the potential utility of liquid biopsy for diagnostic purposes. In conclusion, this study establishes calnexin as a promising target for antibody-based lung cancer diagnosis and therapy, unlocking novel avenues for early detection and treatment.

Improvement of Validity and Efficiency for Detection of Cryptosporidium Ocysts and Giardia Cysts in Environmental Water Samples (환경수 중 크립토스포리디움 오시스트 및 지아디아 시스트 검출의 정확도 및 회수율 향상을 위한 연구)

  • 이목영;조은주;김도연;변승헌;이의광;오세종;안승구
    • Korean Journal of Microbiology
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    • v.39 no.1
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    • pp.27-35
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    • 2003
  • No currently available methods to monitor pathogenic protozoa, Cryptosporidium and Giardia in environmental water come close to acceptable sensitivity, specificity and reproducibility, and so it has to be accompanied by thorough quality control and performance evaluation to credibly predict the distribution of them. We collected surface water samples from the Han River and spiked our prepared (oo)cysts, determined Matrix Spike recoveries using USEPA Method 1623 and considered what factors influence MS recovery and validity. As a result, average 46% of spiked oocysts and 60% of spike cysts were recovered, but repetitive sampling and statistical approach seemed to be necessary to determine the environmental pollution level of two protozoa as their variation coefficients was so much as 35oio and 26%. And MS recoveries with two acid dissociations during immunomagnetic separation were improved more 10% than that with one dissociations and the use of spiked suspension enumerated by flow cytometry instead of manual preparation enhanced the validity and reliability in spiking tests. Because fluorescence characteristics of (oo)cysts stained on well slides with FITC-labeled monoclonal antibodies and DAPI was not always same, well Elides from spiked field samples were helpful to evaluate the performance of staining. We found many (oo)cyst-like objects with typical fluorescence, not (co)cysts, from the Han River water samples, and then it was concluded that nuclei staining by DAPI (4',6-diamidino-2-phenylindole) and examination by Differential Interference Contrast Microscope should be critical for valid identification.

A Study on the Detection Characteristics in Glucose and Fabrication of Bi-Enzyme Electrode using Electrochemical Method (전기화학적 방법을 이용한 다중 효소 전극 제작 및 글루코스 검출 특성에 관한 연구)

  • Han, Kyoung Ho;Shin, In Seong;Yoon, Do-Young
    • Journal of the Korean Electrochemical Society
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    • v.23 no.3
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    • pp.66-72
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    • 2020
  • In this study, the development of biosensors capable of bi-enzyme reactions by including Horseradish peroxidase and glucose oxidase was carried out for detection of glucose. The sensors were manufactured using electro deposition method to reduce production time, and screen printed electrodes (SPE) were used to produce economical sensors. To check the bienzyme effect, the sensor was compared and analyzed with single enzyme biosensor. The characteristics of the sensor were evaluated using scanning electron microscopy(SEM), cyclic voltammetry(CV), electrochemical impedance spectroscopy(EIS), chronoamperometry(CA), and flow injection analysis(FIA). Analysis results from SEM, CV and EIS confirmed that the enzymes are well fixed to the electrode surface. In addition, it was confirmed that bi-enzyme biosensors manufactured from the CA method improved signal performance by 200% compared to single enzyme biosensors. From this results, we were able to explain that HRP and GOD react catalyzed to each other. And the results of FIA showed that the intensity of each current signal was constant when the same concentration of glucose was injected four times. In addition, by analyzing the intensity of current signals for glucose concentrations, the biosensors manufactured in this study showed excellent trends in signal sensitivity, reproducibility and stability.

Detecting TOCTOU Race Condition on UNIX Kernel Based File System through Binary Analysis (바이너리 분석을 통한 UNIX 커널 기반 File System의 TOCTOU Race Condition 탐지)

  • Lee, SeokWon;Jin, Wen-Hui;Oh, Heekuck
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.31 no.4
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    • pp.701-713
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    • 2021
  • Race Condition is a vulnerability in which two or more processes input or manipulate a common resource at the same time, resulting in unintended results. This vulnerability can lead to problems such as denial of service, elevation of privilege. When a vulnerability occurs in software, the relevant information is documented, but often the cause of the vulnerability or the source code is not disclosed. In this case, analysis at the binary level is necessary to detect the vulnerability. This paper aims to detect the Time-Of-Check Time-Of-Use (TOCTOU) Race Condition vulnerability of UNIX kernel-based File System at the binary level. So far, various detection techniques of static/dynamic analysis techniques have been studied for the vulnerability. Existing vulnerability detection tools using static analysis detect through source code analysis, and there are currently few studies conducted at the binary level. In this paper, we propose a method for detecting TOCTOU Race Condition in File System based on Control Flow Graph and Call Graph through Binary Analysis Platform (BAP), a binary static analysis tool.

Blocking Intelligent Dos Attack with SDN (SDN과 허니팟 기반 동적 파라미터 조절을 통한 지능적 서비스 거부 공격 차단)

  • Yun, Junhyeok;Mun, Sungsik;Kim, Mihui
    • KIPS Transactions on Computer and Communication Systems
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    • v.11 no.1
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    • pp.23-34
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    • 2022
  • With the development of network technology, the application area has also been diversified, and protocols for various purposes have been developed and the amount of traffic has exploded. Therefore, it is difficult for the network administrator to meet the stability and security standards of the network with the existing traditional switching and routing methods. Software Defined Networking (SDN) is a new networking paradigm proposed to solve this problem. SDN enables efficient network management by programming network operations. This has the advantage that network administrators can flexibly respond to various types of attacks. In this paper, we design a threat level management module, an attack detection module, a packet statistics module, and a flow rule generator that collects attack information through the controller and switch, which are components of SDN, and detects attacks based on these attributes of SDN. It proposes a method to block denial of service attacks (DoS) of advanced attackers by programming and applying honeypot. In the proposed system, the attack packet can be quickly delivered to the honeypot according to the modifiable flow rule, and the honeypot that received the attack packets analyzed the intelligent attack pattern based on this. According to the analysis results, the attack detection module and the threat level management module are adjusted to respond to intelligent attacks. The performance and feasibility of the proposed system was shown by actually implementing the proposed system, performing intelligent attacks with various attack patterns and attack levels, and checking the attack detection rate compared to the existing system.