• Title/Summary/Keyword: Detection agent

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Characteristics of Trichloroethene and Tetrachloroethene Sensing Optical Fiber Biosensor Using Toluene-o-monooxygenase and Fluoresceinamine (Toluene-o-monooxygenase와 Fluoresceinamine을 이용한 Trichloroethene와 Tetrachloroethene 감지용 광섬유 바이오센서의 특성)

  • Ryoo, Doohyun
    • Journal of Soil and Groundwater Environment
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    • v.23 no.4
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    • pp.42-47
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    • 2018
  • E. coli TG1 pBS TOM Green was cultured to produce toluene-o-monooxygenase (TOM). A biosensor system was successfully constructed using purified TOM to effectively detect trichloroethene (TCE) and tetrachloroethene (PCE), which represent some of the major contaminants in groundwater and soil. In order to utilize TOM as a sensor, NADH, a biological oxidizer, was replaced with hydrogen peroxide which is a chemical oxidizing agent. A three-layered sandwich-type sensing tip was fabricated on the outside of the hydrophilic polyvinylidene fluoride membrane. TCE and PCE were applied to the sensor and the hydrogen ions were measured by a fiber optic fluorometer using fluoresceinamine. Calibration curves were obtained for TCE and PCE in the concentration range of 0.2-100 mg/l, and the detection limit of the system was $10{\mu}g/l$ for TCE and PCE.

Urease를 이용한 위점막 시료에서 Helicobacter pylori의 신속한 진단법

  • Lee, Hak-Seong;No, Im-Hwan;Choe, Tae-Bu;Lee, Jong-Hwa
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.264-265
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    • 2000
  • Helicobacter pylori(H. pylori) is the causative agent of chronic gastritis and the single most important factor in peptic ulcer disease, however, the pathogenetic mechanisms underlying H, pylori infection are not well understood. Futhermore, there is a strong association between H. pylori infection and gastric cancer. Various diagnostic methods for detecting H. pylori infection are available. These can be divided into invasive methods, requiring endoscopy, and non-invasive tests, mainly 13C-urea breath tests and serologic detection of antibodies. Rapid urease test is the most recommendable endoscopic test for the diagnosis of H. pylori infection, presently. CLO test kit is the represent of rapid urease test kits. The principles of CLO test kit is that hydrolysis of urea by urease Is detected by a dye indicators showing a color change. Our device is used same principle but we improved the reaction time is more faster and positive color change is more distinctive from the color of the negative specimen. So, this kit is more reliable because it response faster and accuracy.

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Pulmonary Tuberculosis Diagnosis: Where We Are?

  • Leylabadlo, Hamed Ebrahimzadeh;Kafil, Hossein Samadi;Yousefi, Mehdi;Aghazadeh, Mohammad;Asgharzadeh, Mohammad
    • Tuberculosis and Respiratory Diseases
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    • v.79 no.3
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    • pp.134-142
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    • 2016
  • In recent years, in spite of medical advancement, tuberculosis (TB) remains a worldwide health problem. Although many laboratory methods have been developed to expedite the diagnosis of TB, delays in diagnosis remain a major problem in the clinical practice. Because of the slow growth rate of the causative agent Mycobacterium tuberculosis, isolation, identification, and drug susceptibility testing of this organism and other clinically important mycobacteria can take several weeks or longer. During the past several years, many methods have been developed for direct detection, species identification, and drug susceptibility testing of TB. A good understanding of the effectiveness and practical limitations of these methods is important to improve diagnosis. This review summarizes the currently-used advances in non-molecular and molecular diagnostics.

Hemophilia (혈우병)

  • Yoo, Ki Young
    • Clinical and Experimental Pediatrics
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    • v.49 no.8
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    • pp.821-829
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    • 2006
  • Hemophilia is the most common coagulation disorder. It has a long history. Hemophilia A is caused by FVIII gene mutation, and hemophilia B by FIX gene mutation. Those genes are located on X chromosome long arm. Bleedings in hemophiliacs predominantly occur in joints and muscles. Because those site are insufficient in tissue factor to induce hemostasis. Among joints knee, ankle and elbow are most frequently affected because their synovial structure is vulnerable to injury compared to other joints. Hemophilia is diagnosed with factor assay. Severe hemophilia is below 1% of FVIII : C, moderate between 1% and 5%, mild over 5%. Carrier detection and prenatal diagnosis have been conducted with RFLP-based linkage analysis and DNA sequencing. Mainstay of treatment is factor replacement therapy so far. Bleedings can be controlled by infusion of factor concentrates. Hemophilc arthropathy and muscle contracture are representative sequelae. Complications of facotor replacement therapy are inhibitor development and infections. Hemophiliacs with inhibitor should be managed with large dose factor concentrate, bypassing agent, ITI and immunosuppression. Ultimately, hemophilia could be cured by gene therapy.

Determination of Trace Metals in Waters by FAAS after Enrichment as Metal-HMDTC Complexes Using Solid Phase Extraction

  • Tokalioglu, Serife;Kartal, Senol;Elci, Latif
    • Bulletin of the Korean Chemical Society
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    • v.23 no.5
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    • pp.693-698
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    • 2002
  • A method has been described for the determination of Cu(Ⅱ), Pb(Ⅱ), Ni(Ⅱ), Cd(Ⅱ), Mn(Ⅱ) and Fe(Ⅲ) by flame atomic absorption spectrometry (FAAS) after preconcentration on Amberlite XAD-16 resin, using hexamethyleneammonium-hexamethylenedithiocarbamate (HMA-HMDTC) as a chelating agent, and NH3/NH4Cl buffer solution (pH 9). Influences of various analytical parameters such as pH, concentration of nitric acid, amount of analytes, diverse ions and sample volume were investigated. The relative standard deviation (RSD) and the detection limit (LOD) were found in the range of 0.8-2.9% and 0.006-0.277 ㎍/mL,respectively. Recoveries obtained by the column method were quantitative ( >95%) at optimum conditions.The method was applied to the determination of some metal ions in seawater and wastewater samples. A high preconcentration factor (about 150 for seawater and 75 for wastewater samples) and simplicity are the main advantages of this suggested method.

Design of Fuzzy-Controller for Agent Selection in CNP-applied Security Models (계약망 프로토콜을 적용한 보안 모델에서 에이전트 선택을 위한 퍼지 컨트롤러의 설계)

  • 이진아;조대호
    • Proceedings of the Korea Society for Simulation Conference
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    • 2004.05a
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    • pp.20-24
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    • 2004
  • 광범위한 네트워크의 연결과 이를 이용하는 조직이나 개인의 증가로 인터넷은 정보를 교환하고 거래를 수행하는 주요한 수단이 된 반면에 해커나 바이러스의 침입 또한 증가하여 공격에 쉽게 노출되어있다. 이러한 보안상의 문제점을 해결하기 위하여 컴퓨터나 네트워크 시스템의 활동을 감시할 수 있는 침입 탐지 시스템(IDS)과 같은 보안 요소를 도입하였으며, 탐지에 대한 성능을 향상시키기 위하여 네트워크를 기반으로 하는 다중 침입 탐지 시스템을 응용하여 네트워크에 분산된 에이전트들 중에서 발생된 침입에 알맞은 에이전트를 선택하도록 하여 침입 탐지를 효과적으로 할 수 있게 하였다. 본 연구에서는 보안 시스템의 연동을 위하여 계약망 프로토콜을 적용하였다. 계약망 프로토콜은 분산된 에이전트들 중에서 입찰과정을 통하여 최상의 에이전트를 선택하는데 이때, 에이전트를 선택하는 과정에 있어서 퍼지 규칙 기반 시스템을 적용한 퍼지 컨트롤러를 설계하여 시뮬레이션 한다.

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Prevalence and Detection of Porcine Circovirus 2 in Aborted Fetuses and Stillborn Piglets

  • H, Yoon-chul;Chae, Chan-hee
    • Proceedings of the Korean Society of Veterinary Pathology Conference
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    • 2003.10a
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    • pp.31-31
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    • 2003
  • Porcine circovirus (PCV) is the smallest virus that replicates autonomously in mammalian cells. PCV2 is recongized as the casual agent of postweaning multisystemic wasting syndrome (PMWS).[1] Although the role of PCV2 in reproductive failure requires further clarification, there have been several reports of PCV2-associated reproductive failure. Consistent clinical signs of affected farms include elevated abortion, stillbirths and fetal mummification. The objective of this study was to determine the prevalence of PCV2 in aborted fetuses and stillborn piglets. Second objective was to determine the distribution of PCV2 DNA and antigen in aborted fetuses and stillborn piglets by in situ hybridisation and immunohistochemistry. (omitted)

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A Study on Real-time Intrusion Detection System using Java Agent in Distributed-Network Environment (분산 네트워크 환경에서 자바 에이전트를 이용한 실시간 침입탐지 시스템에 관한 연구)

  • 이명규;이병용;이요섭;전문석
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10c
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    • pp.706-708
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    • 1998
  • 최근 인터넷의 급속한 발전은 컴퓨팅 환경에 혁명적인 변화를 가져왔다. 전 세계에 산재한 컴퓨터가 하나의 단일 망으로 연결되어지고, 손쉽게 정보를 접할 수 있는 등의 많은 이점을 가지게 된 반면 인터넷을 통한 불법 침입도 점차로 증가하고 있는 추세이다. 또한 이러한 침입의 방법도 점차로 복잡하고 다양하며 지능화 되고 있어 침입탐지 시스템이 필요하게 되었다. 하지만 침입행위를 실시간에 탐지하는데 많은 어려움이 있으며, 시스템의 종류에 따라 침입탐지모듈을 작성해야하는 어려움이 있다. 본 논문에서는 자바 에이전트를 이용한 침입탐지 시스템을 제안하여, 침입탐지 모듈을 각 호스트 상에서 동작하는 에이전트와 분산 환경에서 동작하는 에이전트로 구성함으로써, 에이전트간의 통신을 통해 침입의 행위를 효과적으로 탐지할 뿐 아니라 에이전트를 동적으로 추가 및 삭제를 함으로써 실시간에 분산 처리할 수 있도록 설계하였다.

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Design of Intrusion Detection System Model using Attributed Agent (분산 에이젠트를 이용한 침입 탐지 시스템 모델)

  • Jeong, Jong-Keun;Kim, Young-Ho;Lee, Yun-Bae
    • Proceedings of the Korea Information Processing Society Conference
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    • 2000.10a
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    • pp.777-780
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    • 2000
  • 최근 세계적으로 유수한 인터넷 사이트들의 해킹으로 인해 네트워크 보안의 중요성이 강조되고 있다. 네트워크 보안을 위해 방화벽보다는 좀 더 신뢰성이 높은 네트워크 및 시스템에 대한 보안 솔루션으로 침입 탄지 시스템(IDS)이 차세대 보안 솔루션으로 부각되고 있다. 본 논문에서는 기존의 IDS의 단점이었던 호스트 레벨에서 확장된 분산환경에서의 실시간 침입 탐지는 물론 이기종간의 시스템에서도 탐지가 가능한 새로운 IDS 모델을 제안.설계하였다. 그리고, 프로토타입을 구현하여 그 타당성을 검증하였다. 이를 위해 서로 다른 이기종에서 침입 탐지에 필요한 감사 파일을 자동적으로 추출하기 위해서 분산 에이전트를 이용한다.

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Detection of Virulence-Associated Genes in Clinical Isolates of Bacillus anthracis by Multiplex PCR and DNA Probes

  • Kumar, Sanjay;Tuteja, Urmil
    • Journal of Microbiology and Biotechnology
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    • v.19 no.11
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    • pp.1475-1481
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    • 2009
  • Anthrax is a zoonotic disease caused by Bacillus anthracis, and well recognized as a potential agent for bioterrorism. B. anthracis can be identified by detecting the virulence factors genes located on two plasmids, pXO1 and pXO2. The aim of the present study was to determine the presence of virulence genes in 27 isolates of B. anthracis isolated from clinical and environmental samples. For this purpose, multiplex PCR and DNA probes were designed to detect protective antigen (pag), edema factor (cya), lethal factor (lef), and capsule (cap) genes. Our results indicated that all the isolates contained all the above virulence genes, suggesting that the isolates were virulent. To the best our knowledge, this is the first study about the determination of virulence marker genes in clinical and environmental isolates of B. anthracis using multiplex PCR and DNA probes in India. We suggest that the above methods can be useful in specific identification of virulent B. anthracis in clinical and environmental samples.