• Journal of the Korean Chemical Society
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• v.52 no.3
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• pp.273-280
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• 2008

Mycobacterium tuberculosis (MTB) remains a major worldwide public health problem. In recent years, the incidence of MTB has been rising. Rapid and reliable diagnosis of Mycobacterium tuberculosis is essential to initiate correct treatment, avoid severe complications, and prevent transmission. LAMP was used to develop a rapid and sensitive laboratory diagnostic system for the MTB. In this research, the loop-mediated isothermal amplification method (LAMP) that amplifies DNA with high specificity and rapidity at an isothermal condition was evaluated for rapid detection of MTB. Undiluted DNA (2.10 × 106 copy/mL), 10-1, 10-2, 10-3, 10-4, 10-5 and 10-6 (copy/mL) of MTB DNA were amplified by PCR and LAMP to determine the sensitivity of the assay. At results, the LAMP assay reported here has the advantages of rapid amplification, high sensitivity, and high specificity and will be useful for rapid and reliable clinical diagnosis of MTB in hospital clinical laboratory.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.610-616
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• 2013

Loop-mediated isothermal amplification (LAMP) is an emerging detection technology for the amplification of DNA under isothermal conditions. The aim of this study was to develop a rapid and reliable LAMP technique for the detection of Cronobacter sakazakii in milk powder. In order to enhance the sensitivity and specificity, LAMP primers targeting outer membrane protein A (ompA) gene of C. sakazakii were designed using Explorer V4 software. Thirty seven C. sakazakii strains and 13 pathogenic microorganisms were used for comparative detection of C. sakazakii using polymerase chain reaction (PCR), real-time PCR, and LAMP. LAMP developed in this study could specifically detect C. sakazakii strains without cross-reactivity with other foodborne pathogens. LAMP products amplified from ompA gene of C. sakazakii were digested with with HhaI and NruI enzyme. The specificity of LAMP was confirmed by restriction fragment length polymorphism (RFLP) analysis. LAMP could detect C. sakazakii within 1 h without bacterial culture and its detection limit was as low as 1 CFU/mL C. sakazakii in milk. In the comparison of the sensitivity, LAMP showed 10,000- and 100-times higher detection limit than PCR or real-time PCR, respectively. Therefore, this study can conclude that LAMP is a rapid and reliable detection technique for C. sakazakii contaminated in powdered milk.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.437-441
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• 2019

Verticillium wilt disease is caused by a fungal plant pathogen Verticillium dahliae, which attacks commercial crops such as chrysanthemum. The conventional methods so far used to identify this fungal pathogen require high expertise and are time-consuming. Therefore, in this study, we developed an assay for the rapid and specific detection of V. dahliae infection using loop-mediated isothermal amplification (LAMP) method. For this assay, four primers for LAMP were designed for targeting cellulose-growth-specific protein partial mRNA gene in Verticillium dahliae. Under standard condition, the optimum reaction temperature for amplification is around 60 ℃ within 60 minutes. This LAMP assay was designed to amplify only present in V. dahliae. When this LAMP assay applied to the DNAs for four other soil-borne fungi and host plants, no amplification was detected. Therefore, this LAMP assay we developed for V. dahliae is expected to do detection at the early stage of its infection. The fast and reliable detection method will allow us to develop effective management system to monitor and control infection of this pathogen in chrysanthemum plant.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.692-699
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• 2013

In this study, isothermal (350, 375, 400, 425, 450, 500, $850^{\circ}C$) experiments were carried out using a custom-made thermobalance to analyze the thermal decomposition properties of refuse plastic fuel (RPF), which is to be used as a cofiring fuel with a sub-bituminous coal at commercial circulating fluidized bed (CFB) boiler in Korea. In isothermal pyrolysis results, no change in the reaction model was observed in the temperature range of $375{\sim}450^{\circ}C$ and it was revealed that the first order chemical reaction (F1) is the most suitable among 12 reaction models. The activation energy shows similar results irrespective of application of reaction model in that the activation energy was 39.44 kcal/mol and 36.96 kcal/mol when using Arrhenius equation and iso-conversional method ($0.5{\leq}X{\leq}0.9$) respectively. Mean-while, the devolatilization time ($t_{dev}$) according to particle size (d) of RPF could be expressed as $t_{dev}=10.38d^{2.88}$ at $850^{\circ}C$, operation temperature of CFB and for even distribution and oxidation of RPF in CFB boiler, we found that the relationship of average dispersion distance (x) and particle size was $x{\leq}1.58d^{1.44}$.

• Korean Journal of Veterinary Service
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• v.41 no.1
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• pp.29-39
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• 2018

In this study, we developed a sensitive and specific reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for rapid visual detection of foot-and-mouth disease virus (FMDV) circulated in Korea. The RT-LAMP was completed in 40 min at $62^{\circ}C$ and the results of the assay were directly detected by naked eye without any detection process. The assay specifically amplified all 7 serotypes of FMDV RNAs but not amplified other viral and cellular nucleic acids. The sensitivity of the RT-LAMP was $10^2$, $10^3$ and $10^3TCID_{50}/mL$ for serotype O, A and Asia 1 FMDV, respectively, which was comparable to conventional reverse transcription polymerase chain reaction (RT-PCR) and relatively lower than that of real time quantitative RT-PCR (qRT-PCR). Clinical evaluation of the RT-LAMP using different serotypes of Korean and foreign FMDV strains showed a 100% (35/35) agreement with the results of the RT-PCR and qRT-PCR. These results indicated that RT-LAMP assay developed in this study could be a valuable diagnostic method for FMDV monitoring and surveillance.

• Korean Journal of Materials Research
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• v.4 no.3
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• pp.259-267
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• 1994

The effect of processing parameters, temperature, gas concentration, gas flow rate and pressure, were studied on the densification of carbon/carbon composites using a Robust design method in isothermal low-pressure chemical vapor infiltration with a gas system of $C_3H_8-N_2$ After one time of isothermal low-pressure chemical vapor infiltrat.ion, the bulk density of carbon/carbon composites in creased up to 1-9% and apparent porosity of the composites decreased down to 20-50%. ANOVA analysis of the experiment.al data revealed that the important parameters of isothermal lowpressure chemical vapor infiltration were temperature, gas concentration and gas flnw rate. 'There was almost no ~ f f e c t on densification by pressure and interaction between each parameters. In t, he present experimental conditions, the highest bulk density was obtained at $1100^{\circ}C$ temperature, 100% $C_3H_8$, concentration, 100 SCCM flow rate and 5 torr pressure.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.65-70
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• 2010

The distillation rate on LiCl-KCl eutectic salt under different vacuums from 0.5-50 mmHg was first investigated by using both a non-isothermal and a isothermal thermogravimetric (TG) analysis. Based on the non-isothermal TG data, distillation rate equations as a function of the temperature could be derived. Calculated flux by these model flux equations was in agreement with the distillation rate obtained from isothermal TG analysis. A distillation rate of $10^{-4}-10^{-5}$ mole $cm^{-2}sec^{-1}$ is obtainable at temperatures less than 1300K and vacuums of 0.5-50 mmHg. About a 99% salt distillation efficiency was obtained after an hour at a temperature above 1150 K under 50 mmHg in a small scale distillation test system. An increase in the vaporizing surface area is relatively effective for removing residual salt in the remaining particles, when compared to that for the vaporizing time. Over 99.95% of total distillation efficiency was obtained for a 1-h distillation operation by increasing the inner surface area from $4.52cm^2$ to $12.56cm^2$.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.3
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• pp.237-243
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• 2015

In this research, isothermal conduction calorimetry analysis has been conducted to investigate the reactivity of alkali activated slag binders. In order to secure the reactivity and workability of alkali activated slag binders, experiences with various types and concentrations of alkali activators were performed. Isothermal conduction calorimetry were measured with different alkali activators and mass ratio of $SO_3$ to binders as variables, and sodium tripolyphosphate ($Na_2P_3O_{10}$) and hydrated sodium borate ($Na_2B_4O_710H_2O$) were used to control setting time. As a results, alkali activated slag binders required alkali activators with 4 to 5 percent of concentration to accelerate the formation of calcium silicate hydrate(C-S-H) by alkali-activation, and overall heat generation rate delayed as accumulated heat decreased due to the high $SO_3$ contents. Moreover, the use of hydrated sodium borate as setting retarder causes elongated setting time due to delaying heat generation, so it can be considered that setting retarder played an important role in delaying total heat generation rate.

• Polymer(Korea)
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• v.36 no.2
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• pp.245-250
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• 2012

Branched polypropylenes (PP) with long chain branch were prepared by solid state reaction with three different branching agent of 0.3 wt% content. The chemical structures, non-isothermal crystallization behavior and complex viscosity of the branched PP were investigated by FTIR, DSC, optical microscope, and dynamic rheological measurement. The chemical structure of the branched PP was confirmed by the existence of =C-H stretching peak of the branching agent at 3100 $cm^{-1}$. There was no distinct change in melting temperature in case of PP-D-0-3 and PP-F-0-3, but PP-H-0-3 indicated a decrease in melting temperature. The decrease in melting temperature was interpreted by the fact that the degradation reaction of PP was more dominant than branched reaction, and confirmed by a decrease in complex viscosity. The non-isothermal crystallization behavior of the branched PP was analyzed using by Avrami equation. The Avrami exponent of PP was 3, and the values of the branched PP with DVB and FS were below 3. The activation energy of PP calculated by Kissinger method was 25 kJ/mol, and there were no big difference in activation energies of the branched PPs compared to PP.

• Journal of the Korean Ceramic Society
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• v.25 no.4
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• pp.329-334
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• 1988

Kinetics of grain growth in PLZT ceramics during isothermal heat treatment and hot-pressing were investigated and the published data on grain growth were reanalyzed. It was found, in many cases, that the errors were introduced by ignoring the initial grain size. The grain growth of PLZT ceramics was confirmed to follow the parabolic normal growth : D2-Do2=Kt.