• Title/Summary/Keyword: LAMP

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Development of a diagnostic method for human enteric Adenovirus-41 with rapid, specific and high sensitivity using the loop-mediated isothermal amplification assay

  • Lee, Jin-Young;Rho, Jae Young
    • Korean Journal of Agricultural Science
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    • v.47 no.3
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    • pp.673-681
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    • 2020
  • Human enteric Adenovirus 41 (HueAdV-41) is a major waterborne virus that causes human gastroenteritis and is classified as a viral group I double-strand DNA virus, Adenoviridae. HueAdV-41 has been detected with the polymerase chain reaction (PCR) in various samples such as ground water. However, the PCR-based diagnostic method has problems such as reaction time, sensitivity, and specificity. Thus, the loop-mediated isothermal amplification (LAMP) assay has emerged as an excellent method for field applications. In this study, we developed a LAMP system that can rapidly detect HueAdV-41 with high specificity and sensitivity. HueAdV-41 specific LAMP primer sets were tested through a specific, non-specific selection and sensitivity test for three prepared LAMP primer sets, of which only one primer set and optimum reaction temperature were selected. The developed LAMP primer set condition was confirmed as 63℃, and the sensitivity was 1 copy. In addition, to confirm the system, a LAMP positive reaction was developed with the restriction enzyme Taq I (T/GCC). The developed method in this study was more specific, rapid (typically within 2 - 3 hours), and highly sensitive than that of the conventional PCR method. To evaluate and verify the developed LAMP assay, an artificial infection test was done with five cDNAs from groundwater samples, and the results were compared to those of the conventional PCR method. We expect the developed LAMP primer set will be used to diagnose HueAdV-41 from various samples.

Scanning Backlight Driver for Mercury Free Flat Fluorescent Lamp (무수은 면광원 램프용 Scanning Backlight 구동회로)

  • Oh, Eun-Tae;Jung, Yong-Min;Lee, Kyung-In;Yoo, Ho-Won;Lee, Jun-Young
    • The Transactions of the Korean Institute of Power Electronics
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    • v.14 no.1
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    • pp.8-14
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    • 2009
  • A lamp which is currently employed to LCD(Liquid Crystal Display) Backlight is almost CCFL(Cold Cathod Fluorescent Lamp) and EEFL(External Electrode Fluorescent Lamp). However, the use of these lamps is being restricted as RoHS(the Restriction of the use of certain Hazardous Substances in electrical and electronic equipment) regulation is gradually reinforced. According to this situation, the manufacturing of a lamp which doesn't use mercury is unescapable. Moreover, LCD TV has a defect which take place Motion Blur phenomenon due to response time of LC(Liquid Crystal), and Hold-type characteristic which only exists in LCD differently to CRT, PDP. In this paper, an inverter is proposed to drive a plane light source lamp which is not containing mercury. Driving circuit of proposed inverter is simple because the number of semiconductor device and magnetic device is reduced by using forward topology. Also, Motion Blur phenomenon is decreased by dividing the plane light source lamp to six block along vertical direction, and scanning. Finally, we proved usefulness of proposed inverter through experiment.

Non-Invasive Colorimetric Magneto Loop-Mediated Isothermal Amplification (CM-LAMP) Method for Helicobacter pylori Detection

  • Bangpanwimon, Khotchawan;Mittraparp-arthorn, Pimonsri;Srinitiwarawong, Kanchana;Tansila, Natta
    • Journal of Microbiology and Biotechnology
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    • v.31 no.4
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    • pp.501-509
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    • 2021
  • More than half the world's population is thought to be infected with Helicobacter pylori. Although the majority of infected people are asymptomatic, H. pylori infection may cause gastric ulcers and deadly gastric cancer. Owing to the difficulty and invasiveness of current routine culture and diagnostic methods, a highly sensitive and specific noninvasive assay for H. pylori is of interest. This study highlighted the design and performance of a colorimetric magneto loop-mediated isothermal amplification (CM-LAMP) assay to detect H. pylori in spiked saliva samples. LF primers were coated on magnetic nanoparticles by carbodiimide-induced immobilization and functionally used for solid-phase amplification. During the LAMP reaction at 66℃, biotin-tagged FIPs were incorporated into LAMP amplicons. The colorimetric signal developed after the addition of NeutrAvidin horseradish peroxidase conjugate (NA-HRP) and ABTS. None of the tested microorganisms, including closely related bacteria, was shown positive by the CM-LAMP assay except H. pylori isolates. This novel platform was highly specific and 100-fold more sensitive (40 CFU/ml or 0.2 CFU per reaction) than the PCR and conventional LAMP assays for the detection of H. pylori in spiked saliva. Our results demonstrated the feasibility of using this noninvasive molecular diagnostic test to detect H. pylori in saliva samples.

Development of reverse transcription loop-mediated isothermal amplification assays for point-of-care testing of avian influenza virus subtype H5 and H9

  • Zhang, Songzi;Shin, Juyoun;Shin, Sun;Chung, Yeun-Jun
    • Genomics & Informatics
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    • v.18 no.4
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    • pp.40.1-40.8
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    • 2020
  • Avian influenza (AIV) outbreaks can induce fatal human pulmonary infections in addition to economic losses to the poultry industry. In this study, we aimed to develop a rapid and sensitive point-of-care AIV test using loop-mediated isothermal amplification (LAMP) technology. We designed three sets of reverse transcription LAMP (RT-LAMP) primers targeting the matrix (M) and hemagglutinin (HA) genes of the H5 and H9 subtypes. RT-LAMP targeting the universal M gene was designed to screen for the presence of AIV and RT-LAMP assays targeting H5-HA and H9-HA were designed to discriminate between the H5 and H9 subtypes. All three RT-LAMP assays showed specific amplification results without nonspecific reactions. In terms of sensitivity, the detection limits of our RT-LAMP assays were 100 to 1,000 RNA copies per reaction, which were 10 times more sensitive than the detection limits of the reference reverse-transcription polymerase chain reaction (RT-PCR) (1,000 to 10,000 RNA copies per reaction). The reaction time of our RT-LAMP assays was less than 30 min, which was approximately four times quicker than that of conventional RT-PCR. Altogether, these assays successfully detected the existence of AIV and discriminated between the H5 or H9 subtypes with higher sensitivity and less time than the conventional RT-PCR assay.

Electrical Characteristics and Discharge Condition of Ceramic Metal Halide Lamp with Operating Property (구동특성에 따른 세라믹 메탈 할라이드 램프의 전기적 특성 및 방전현상에 관한 연구)

  • Jang, Hyeok-Jin;Kim, Nam-Gon;Yang, Jong-Kyung;Kim, Woo-Young;Park, Hyung-Jun;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.388-389
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    • 2009
  • The use of arc tubes made of ceramic material further enhanced some of the metal halide lamp's properties. These properties translate into higher efficacy with better color rendering, stable color through lamp long life. Recently, due to an increase in the application of the ceramic metal-halide lamp, the study for the property etc. according to Ballast's driving scheme and the study for arc tube material, optimization of gas and so on are being proceeded to improve the property of the lamp. Especially, to control ceramic metal-halide lamp, the vigorous study and practical use with respect to Electronic Ballast, which has been improved in the disadvantages of the conventional Magnetic Ballast are made. In this paper, Electrical characteristics and gas insulation destroy time are analyzed by comparing magnetic ballast with electronic ballast.

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Analysis of Effects on the performance of ceramic metal halide lamp by the loss of elements that have been filled in arc tube

  • Jang, Hyeok-Jin;Yang, Jong-Gyeong;Lee, Jong-Chan;Kim, U-Yeong;Sin, Ik-Tae;Park, Dae-Hui
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.219-219
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    • 2009
  • ceramic metal halide lamps are a subset of high intensity discharge lamps so named because of their high radiance These lamps weak ionized plasma in a fire-resisting but light transmissive wrapping by the corridor of current through atomic and molecular vapors. for commercial applications, For commercial applications, the conversion of electric power to light must occur with good efficiency and with sufficient spectral content throughout the visible (380-800 nm) to permit the light so generated to render colors comparable to natural sunlight. the purpose of this paper is to carry out a study on the variation of ageing time(2000 On/Off[hr]) on the performance of 150W CMH lamps. Experimental results show that the blackening by reacting W(tungsten)with I atomic has been created in the arc tube of an ageing lamp(2000 On/Off[hr]), the arc was unstable, and increased a lamp resistance made lamp voltage increases significantly. Also, Color temperature of the ageing lamp was moved by the losses of Ho with Dy atomics and by recombination of Na with I.

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Development of Electronic Ballast for Metal Halide Lamp wilts Free Voltage Input (프리볼트입력용 메탈핼라이드램프 전자식안정기 개발)

  • 김기정
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.16 no.1
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    • pp.20-26
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    • 2002
  • HID(high intensity discharge)lamps include high pressure mercury lamp, high pressure sodium lamp and metal halide lamp. Metal halide lamps have been considered to be one of the most erective light sources. These lamps have good efficiency, good color rendering and good focusing capability. The objective of this research is to alum on the metal halide lamp(MH70W) by the developed electronic ballast with free voltage input(AC 100∼277V). The developed electronic ballast consists of a free voltage input converter, a flyback converter & half-bridge inverter, ignitor & protector and control1er. Experimental results show that developed electronic ballast turns on the metal halide lamp(MH70W) with free voltage input(AC 100∼277V) very well.

Transmittance properties of fishing lamp in distant-water squid jigging vessel (원양 오징어채낚기 집어등 불빛의 수중 투과 특성)

  • Jo, Hyun-Su;Oh, Taeg-Yun;Kim, Yeong-Seung;Moon, Dae-Yeon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.42 no.4
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    • pp.228-233
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    • 2006
  • The transmittance properties of fishing lamp of the squid jigging vessel was investigated during nighttime operations in the Northwest Pacific on 21 and 29 September 2005. The metal halide lamps of white color($2.0kW{\times}168$) in the air and metal halide lamp of white color($10.0kW{\times}1$) in the underwater were used as a fishing lamp for gathering squids. The relative irradiance of metal halide lamp in the air showed peak in 850nm of wave length. The relationship between underwater illuminance(Y) and water depth(X) of metal halide lamp light in the observation areas is represented, $Y=84.137e^{-0.1105X},\;R^2=0.9974$. The distribution of underwater illuminance of measure points St. 1-5 showed low value of 0.11x in 80m depth.

Design Method for Flowing Water Purification with UV Lamp (UV램프를 이용한 유수처리형 살균장치의 설계방법)

  • Jung, Byung-Kyun;Lee, Jin-Jong;Jeong, Byeong-Ho
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.58 no.4
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    • pp.455-460
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    • 2009
  • A number of factors combine to make ultraviolet radiation a superior means of water purification for ground water, rainwater harvesting systems and so on. Ultraviolet radiation is capable of destroying all types of bacteria. Additionally, ultraviolet radiation disinfects rapidly without the use of heat or chemical additives which may undesirably alter the composition of water. In a typical operation, water enters the inlet of a UV lamp and flows through the annular space between the quartz sleeve and the outside chamber wall. The irradiated water leaves through the outlet nozzle. Several design features are combined to determine the dosage delivered. The first is Wavelength output of the lamp, the Second is Length of the lamp - when the lamp is mounted parallel to the direction of water flow, the exposure time is proportional to the length of the lamp, the third is Design water flow rate - exposure time is inversely related to the linear flow rate, the forth is Diameter of the purification chamber - since the water itself absorbs UV energy, the delivered dosage diminishes logarithmically with the distance from the lamp. In this paper, It describe the how to design optimal UV disinfection device for ground water and rainwater. To search the optimal design method, it was performed computer simulation with 3D-CFD discrete ordinates model and manufactured prototype. Using proposed design method manufactured prototype applied to disinfection test and proved satisfied performance.

Analysis of Impulse Withstand Voltage Performance of Lighting Equipment (조명기기의 임펄스내전압 성능의 분석)

  • Lee, Bok-Hee;Pang, Pyung-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.3
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    • pp.91-96
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    • 2014
  • Modern electronic circuits are becoming more vulnerable to damage by surges, and it is required to improve the impulse withstand voltage performance of electrical and electronic equipment. This paper presents the impulse withstand voltage performance of lighting equipment connected to power lines, and the impulse withstand voltage tests for fluorescent lamp, LED lamp and halogen lamp were carried out according to the reference standards under normal service conditions. To conduct performance tests against lightning surge, a combination wave ($1.2/50{\mu}s$ voltage - $8/20{\mu}s$ current) was employed. The test surge was applied between lines or between line and ground of the specimen to be measured. The test surge was applied synchronized at the peak value of the positive and negative AC voltage waves. As a consequence, some specimens satisfied the impulse withstand voltage test criteria, but lighting equipment such as 36W fluorescent lamps, 5W and 5.5W LED lamps and 50W halogen lamp were damaged at the test voltage levels between power lines. It is needed to improve the qualities of lighting equipment to satisfy EMC immunity requirements of equipment for general lighting purposes.