• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.524-528
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• 2001

The measurement of radiation response using simple and informative techniques would be of great value in studying the genetic risk following occupational, therapeutic, or accidental exposure to radiation. When patients receive radiation therapy, many suffer from side effects. Since each patient receives a different dose due to different physical conditions, it is important to measure the exact dose of radiation received by each patient to lessen the side effects. Even though several biological dosimetric systems have already been developed, there is no ideal system that can satisfy all the criteria for an idean dosimetric system, especially for low-dose radiation as used in radiation therapy. In this study, an SOS Chromotest of E. coli PQ37 was evaluated as a novel dosimeter for low-dose gamma-rays. E. coli PQ37 was originally developed to screen chemical mutagens using the SOS Chromotest-a colorimtric assay, based on the induction of ${\beta}$-galactosidase ue to DNA damage. The survival fraction of E. coli PQ37 decreased dose-dependently with an increasing dose of cobalt-60 gamma-rays. Also, a good linear correlation was found between the biological damage revealed by the ${\beta}$-galactosidase expression and the doses of gamma-rays. The expression of ${\beta}$-galactosidase activity that responded to low-dose radiation under 1 Gy was $Y=0.404+(0.089{\pm}0.3)D+(-0.018{\pm}0.16)D^2$ (Y, absorbance at 420 nm; D, Dose of irradiation) as calculated using Graph Pad In Plot and Excel. When a rabbit was fed with capsules containing an agar block embdded with E. coli PQ37 showed a linear response to the radiation doses. Accordingly, the results confirm that E. coli PQ37 can be used as a sensitive biological dosimeter fro cobalt-60 gamma-rays. To the best of our knowledge, this is the first time that a bacterium has been used as a biological dosimeter, especially for low-dose radiation.

• Journal of Hydrogen and New Energy
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• v.18 no.4
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• pp.365-373
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• 2007

We optimized the compositions of electrolyte and additives for anode in Ni-MH battery to improve the electrode characteristics at ambient and low temperatures using response surface method(RSM). Among various additives for anode, PTFE exhibited the greatest influence on the discharge capacity of the anode. Through response optimization process, we found the optimum composition of the additives to exhibit the greatest discharge capacity. When the amount of additives was too small, the anode was degraded with time due to the low binding strength among alloy powders and the resultant separation of powders from the current collector. In contrast, the addition of large amount of the additives increased in the resistance of the electrode. In addition, the discharge capacity of the anode at $-18^{\circ}C$ increased with decreasing the concentration of KOH, NaOH and LiOH in design range of electrolyte. The resistance and viscosity of electrolyte appear to affect the discharge capacity of the anode at low temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.6
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• pp.512-517
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• 1990

This experiment was conducted to evaluate the tillering behavior of low- and high-tillering rice plants, IR58. a high-tillering cultivar with small panicles showed not only higher tiller number but also earlier tillering, faster tillering rate and longer tillering duration than IR25588. a low-tillering cultivar with large panicles, Tillering ability of IR25588 was only 59% that of IR58, Percent effective tillers was higher in IR25588(85%) than in IR58 (67%), Tillering response to wider spacing was higher in a high-tillering cultivar than in a low-tillering cultivar, Grain yield response to closer spacing (close spacing adaptability) was higher in a low-tillering cultivar than in a high-tillering cultivar.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.662-667
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• 2020

Epidermal growth factor receptor (EGFR) mutations are not only genetic markers for diagnosis but also biomarkers of clinical-response against tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC). Among the EGFR mutations, the in-frame deletion mutation in EGFR exon 19 kinase domain (EGFR exon 19-del) is the most frequent mutation, accounting for about 45% of EGFR mutations in NSCLCs. Development of sensitive method for detecting the EGFR mutation is highly required to make a better screening for drug-response in the treatment of NSCLC patients. Here, we developed a fluorometric tandem gene amplification assay for sensitive detection of low-abundance EGFR exon 19-del mutant genomic DNA. The method consists of pre-amplification with PCR, thermal cycling of ligation by Taq ligase, and subsequent rolling circle amplification (RCA). PCR-amplified DNA from genomic DNA samples was used as splint DNA to conjugate both ends of linear padlock DNA, generating circular padlock DNA template for RCA. Long stretches of ssDNA harboring multiple copies of G-quadruplex structure was generated in RCA and detected by thioflavin T (ThT) fluorescence, which is specifically intercalated into the G-quadruplex, emitting strong fluorescence. Sensitivity of tandem gene amplification assay for detection of the EGFR exon 19-del from gDNA was as low as 3.6 pg, and mutant gDNA present in the pooled normal plasma was readily detected as low as 1% fraction. Hence, fluorometric detection of low-abundance EGFR exon 19 deletion mutation using tandem gene amplification may be applicable to clinical diagnosis of NSCLC patients with appropriate TKI treatment.

• Nuclear Engineering and Technology
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• v.56 no.5
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• pp.1712-1724
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• 2024

Spiral tubes are used in a wide range of applications and it is significant to understand the vibration introduced by two-phase flow in spiral tubes. In this paper, the numerical method is used to study the vibration induced by the gas-liquid two-phase flow in a spiral tube with different flow regimes. The pressure fluctuation characteristics at the pipe wall and the solid vibration response characteristics are obtained. The results show that the motion of small bubbles in bubbly flow leads to small pressure fluctuations with low-frequency broadband (0-50 Hz). The motion of the gas plug in the plug flow causes small amplitude periodic pressure fluctuation with a shortened low-frequency broadband (0-15 Hz) compared to the bubbly flow. The motion of the gas slug in the slug flow causes large periodic fluctuations in pressure with a significant dominant frequency (6-7 Hz). The wavy flow is very stable and has a distinct main frequency (1-2 Hz). The vibration regime in the bubbly flow and wave flow are close to the first-order mode, and the vertical vibrating component is dominant. The plug flow and slug flow excite higher-order vibration modes, and the lateral vibration component plays more important part in the vibration response.

• Clinical Nutrition Research
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• v.13 no.3
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• pp.186-200
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• 2024

Meta-analyses have been conducted with conflicting results on this topic. Due to missing several eligible studies in previous meta-analysis by Lam et al., we conducted an extensive systematic review and dose-response meta-analysis of randomized controlled trials in this regard. A comprehensive search was conducted across various databases, including MEDLINE/PubMed, ISI Web of Knowledge, Scopus, and Google Scholar, until November 2023. Based on the analysis of 33 studies comprising 2,047 individuals, it was found that there was a significant increase in body weight for each 1 g/day increase in omega-3 lipids (standardized MD [SMD], 0.52 kg; 95% confidence interval [CI], 0.31, 0.73; I² = 95%; Grading of Recommendations Assessment, Development and Evaluation [GRADE] = low). Supplementation of omega-3 fatty acids did not yield a statistically significant impact on body mass index (BMI) (SMD, 0.12 kg/m²; 95% CI, -0.02, 0.27; I² = 79%; GRADE = very low), lean body mass (LBM) (SMD, -0.02 kg; 95% CI, -0.43, 0.39; I² = 97%; GRADE = very low), fat mass (SMD, 0.45 kg; 95% CI, -0.25, 1.15; I² = 96%; GRADE = low), and body fat (SMD, 0.30%; 95% CI, -0.90, 1.51; I² = 96%; GRADE = very low). After excluding 2 studies, the findings were significant for BMI. Regarding the results of the dose-response analysis, body weight increased proportionally by increasing the dose of omega-3 supplementation up to 4 g/day. Omega-3 fatty acid supplementation can improve body weight, but not BMI, LBM, fat mass, or body fat in cancer patients; large-scale randomized trials needed for more reliable results.

• Journal of Sensor Science and Technology
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• v.17 no.4
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• pp.303-307
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• 2008

$NiO,\;Cu_2O,\;Mn_2O_3$ and $Cr_2O_3$ as p-type semiconductors were added in CoO with 15 wt.% ethylene glycol binder and measured the butane gas sensing characteristics. The highest sensitivity is obtained for the NiO-CoO sensors. CoO-20 at.% NiO sensor with 15 wt.% ethylene glycol binder sintered at $1100^{\circ}C$ for 24 h exhibits high sensitivity of 90 % to 5000 ppm butane gas at the sensor temperature of $250^{\circ}C$, compared to low sensitivities at the low operating temperature for commercial sensors. Response and recovery times are, respectively, within few seconds and 1min in the static flow system, indicating rapid adsorption and desorption of butane gas on sensor surface even at this low temperature.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.459-463
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• 2003

Waveform inversion requires extracting a reliable low frequency content of seismic data for estimating of the low wave number velocity model. The low frequency content of the seismic data is usually discarded or neglected because of the band-limited response of the source and the receivers. In this study, however small the spectral of the low frequency seismic data is, we assume that it is possible to extract a reliable phase information of the low frequency from the seismic data and use it in waveform inversion. To this end, we exploit the frequency domain finite element modeling and source-receiver reciprocity to calculate the $Frech\`{e}t$ derivative of the phase of the seismic data with respect to the earth model parameter such as velocity, and then apply a damped least squares method to invert the phase of the seismic data. Through numerical example, we will attempt to demonstrate the feasibility of our method in estimating the correct velocity model for prestack depth migration.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.10
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• pp.708-711
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• 2000

Sensorless PMSM is much studied for the industrial applications and home appliances because a mechanical sensor reduce reliability and increase cost. Most of sensorless algorithms are based on motor equations, and so the magnitude of phase voltage and current should be exactly obtained. However, the inverter output voltage applied to PMSM has relatively large error in the low speed range, and a relatively poor response is shown in the low speed range. This paper investigates the improved performance of sensorless PMSM in the low speed range. This paper proposes the error reduction of inverter output voltage which is realized through the variable link voltage. The proposed algorithm is verified through simulation and experiment.

• Korean Journal of Acupuncture
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• v.37 no.3
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• pp.191-197
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• 2020

This case study reports the clinical response to Korean Medicine (KM) treatments including capsaicin-containing (CP) pharmacopuncture in three patients with acute low back and hip pain. Three patients were diagnosed with acute lumbar sprain, and were treated with CP pharmacopuncture, and other KM treatments including acupuncture, cupping, and herbal medicine. Numeric Rating Scale (NRS), Oswestry Disablility Index (ODI), and Clinical Evaluation Grade (CEG) were used to evaluate symptom changes. After one or two treatments, acute pain with limited range of motion in the low back and thigh region improved with a decrease in NRS, ODI, and CEG. These results suggest that further studies on KM treatments including CP pharmacopuncture for acute low back and hip pain are warranted.