• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.370-373
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• 2000

Acute toxicity of the pigment fraction of Heugjinjubyeo was investigated in male and female mice following oral administration. Major component of pigment fraction was analyzed as cyanidin 3-glucoside (C3G), which composition content was 96%. The pigment fraction as given at the single oral doses of 1000,3000 and 9000mg/kg in male and female mice did not show any abnormal behaviours, body weight loss or other toxic symptoms during observation period of 14 days. There were no dead mice among 6 mice at a single dose of 9000mg/kg. Thus, it is concluded that the minimum lethal doses (MLD) of the pigment extract might be more than 9000 mg/kg p.o., in male and female mice.

• YAKHAK HOEJI
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• v.51 no.5
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• pp.355-360
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• 2007

The essential oil fraction from the aerial parts of A. annua was analyzed by GC-MS. As the results, caryophyllene oxide (11.7%), caryophyllene (7.54%), camphor (7.32%), 1,8-cineol (4.98%), and borneol (3.99%) were confirmed as the main components of the oil fraction. The effects of this oil and its main components on antibiotic-susceptible and -resistant strains of Salmonella enteritidis and S. typhimurium were assessed. A. annua oil fraction significantly inhibited all strains of the two Salmonella species examined, with minimum inhibiting concentrations (MICs) ranging from 2.0 mg/ml to 8.0 mg/ml. Among the main components of the oil, borneol and camphor showed relatively strong inhibiting activity with MICs between 1.0 mg/ml and 4.0 mg/ml. The MICs of caryophyllene and caryophyllene oxide were higher than 16 mg/ml. The combination effects of the oils with kanamycin were evaluated using a checkerboard microtiter assay. Against S. typhimurium KCCM11862 and CCARM8009 strains, the oil fraction of A. annua, camphor, and 1,8-cineol exhibited significant synergistic with kanamycin with fractional inhibitory concentration (FIC) indices in the range of 0.085 to 0.375. In conclusion, a combination of kanamycin and A. annua oil or its main component, camphor, and cineol, may be useful for reducing the minimum effective dose of antibiotic required for the treatment of resistant S. typhimurium infections.

• The Journal of the Korea Contents Association
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• v.3 no.1
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• pp.9-13
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• 2003

We propose a block motion estimation algorithm based on a statistical image feature for video sequences. The statistical feature of the reference block is obtained, then applied to select the candidate starting points (SPs) in the regular starting points pattern (SPP) by comparing the statistical feature of reference block with that of blocks which are spread ower regular SPP. The final SPs are obtained by their Mean Absolute Difference(MAD) value among the candidate SPs. Finally, one of conventional fast search algorithms, such as BRGDS, DS, and three-step search (TSS), has been applied to generate the motion vector of reference block using the final SPs as its starting points. The experimental results showed that the starting points from fine SPs were as dose as to the global minimum as we expected.

• Journal of Apiculture
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• v.34 no.2
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• pp.131-136
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• 2019

Recently, number of honeybees (Apis mellifera) has visibly decreased because they are vulnerable to some diseases like American foulbrood disease. American foulbrood disease, which is caused by Paenibacillus larvae, is emerged as great cause of decrease in number of honeybees. After antibiotic-resistant strain emerged, it is now more difficult to treat those pathogens successfully. Researches on finding alternative antibacterial compound are ongoing. In this study, we examined the antibacterial effect of honokiol on P. larvae. Honokiol showed great antibacterial effect with minimum inhibitory concentration of 12.5 ㎍/mL and minimum bactericidal concentration of 50 ㎍/mL. An agar diffusion test also confirmed the anti-Paenibacillus larvae activity of honokiol with an inhibitory zone of 9±0.5 mm. Since honokiol is known to interact membrane of some bacteria, we measured 260 nm absorbing particles, which could be induced by leakage of cells, and confirmed that the leakage of P. larvae occurred in dose-dependent manners. However, result of crystal violet assay suggested that honokiol has only mild anti-biofilm formation effect on P. larvae, which means honokiol controls the bacteria by inducing the bursting of membrane. Finally, an additive effect of honokiol with tetracycline and terramycin was found using a checkerboard assay with a fractional inhibitory concentration index value of 0.5.

• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.83-87
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• 2021

Antimicrobial activity of an aqueous extract from Caesalpinia sappan L. was investigated against skin flora such as Escherichia coli, Staphylococcus aureus, Cutibacterium acnes, and Malassezia furfur. The yield and polyphenol content of the aqueous extract were 14.01±0.81% and 487.5±19.69 ㎍/mg-extract, respectively. The minimum inhibitory concentration of the aqueous extract against E. coli, S. aureus, C. acnes, and M. furfur was 0.875, 1.750, 1.750, and 1.750 mg/mL, respectively. In disc diffusion test, the aqueous extract of C. sappan L. increased the clear zone in a dose-dependent manner. The aqueous extract inhibited the microbial growth in a concentration-dependent manner.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.3176-3180
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• 2022

A gamma irradiator is a well-developed installation for gamma radiation sterilization. A "shuffle-dwell" mode is preferable for high dose applications. A novel configuration of a shuffle-dwell gamma irradiator is proposed to increase energy utilization and throughput, which would result in higher profitability. While the minimum distance between any irradiation position and each source pencil, the minimum distance between the neighboring irradiation positions and the size of source pencils are kept the same as the current configuration, the irradiation positions and source pencils are rearranged based on the fact that radiation is emitted in an isotropic fashion. The computational results suggest that the proposed configuration requires an 8.7% smaller area and exposes the product to 11.8% more gamma radiation in a 10.7% shorter irradiation time. In other words, the proposed configuration needs a smaller area and shorter irradiation time to have a better performance compared to the current shuffle-dwell gamma irradiator. Note that the claim is based primarily on an analytical calculation. Experimental and manufacturing among other practical considerations will be taken into account in the future work to exhaustively evaluate the performance of the proposed configuration and to compare it with that of the traditional configuration.

• Journal of Pharmacopuncture
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• v.25 no.1
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• pp.37-45
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• 2022

Objectives: The quorum-sensing-inhibitory and anti-biofilm activities of the methanol extract of E. globulus leaves were determined against clinically isolated multidrug-resistant Pseudomonas aeruginosa. Methods: The preliminary anti-quorum-sensing (AQS) activity of eucalyptus was investigated against a biosensor strain Chromobacterium violaceum ATCC 12472 (CV12472) by using the agar well diffusion method. The effect of sub-minimum inhibitory concentrations (sub-MICs) of the methanol extract of eucalyptus on different quorum-sensing-regulated virulence factors, such as swarming motility, pyocyanin pigment, exopolysaccharide (EPS), and biofilm formation, against clinical isolates (CIs 2, 3, and 4) and reference PA01 of Pseudomonas aeruginosa were determined using the swarm diameter (mm)-measurement method, chloroform extraction method, phenol (5%)-sulphuric acid (concentrated) method, and the microtiter plate assay respectively, and the inhibition (%) in formation were calculated. Results: The preliminary AQS activity (violacein pigment inhibition) of eucalyptus was confirmed against Chromobacterium violaceum ATCC 12472 (CV12472). The eucalyptus extract also showed concentration-dependent inhibition (%) of swarming motility, pyocyanin pigment, EPS, and biofilm formation in different CIs and PA01 of P. aeruginosa. Conclusion: Our results revealed the effectiveness of the E. globulus extract for the regulation of quorum-sensing-dependent virulence factors and biofilm formation at a reduced dose (sub-MICs) and suggest that E. globulus may be a therapeutic agent for curing and controlling bacterial infection and thereby reducing the possibility of resistance development in pathogenic strains.

• Biomedical Science Letters
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• v.29 no.3
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• pp.130-136
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• 2023

In this study, the anti-bacterial activity of three medicinal herbs such as Dioscorea batatas, Morus alba, and Tagetes erecta, have been applied in oriental medicine against Escherichia coli and Staphylococcus aureus. The antibacterial activity of Dioscorea batatas ethanol extract (DBEE), Morus alba ethanol extract (MAEE), and Tagetes erecta ethanol extract (TEEE) was analyzed by disk diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays. As a result, three medicinal herbs exhibited antibacterial activity in a dose-dependent manner as well as MAEE and TEEE showed the most potent antibacterial activity followed by disk diffusion assay against E. coli and S. aureus, respectively. MIC against E. coli and S. aureus was 1.6 mg/mL of MAEE and TEEE as well as 0.2 mg/mL of TEEE. MBC against both strains was 5 mg/mL of DBEE and 2.5 mg/mL of TEEE. Consequently, three medicinal herbs in this study showed potent antibacterial activity through the inhibited growth of E. coli and S. aureus, which is considered as a potential candidate for cosmeceutic agents to attenuate the pruritus. In addition, antibacterial and antihistamine effects followed by the extraction solvents should be analyzed in future studies.

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.1
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• pp.23-30
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• 1980

The reconstruction problem in a low dose case requires some compromise of resolution and noise artifacts, and also some modification of filter kernels depending on the signal-to-noise ratio of projection data. In this paper, ail algorithm for the reconstruction of an image function from noisy projection data is suggested, based on minimum-mean-square error criterion. Modification of the falter kernel is made from information (statistics) obtained from the projection data. The simulation study Proves that this algorithm, based on the Wiener falter approach, provides substantially improved image with reduction of noise as well as improvement of the resolution. An approximate method was also studied which leads to the possible use of a recursive filter in the convolution process of image reconstruction.

• Korean Journal of Head & Neck Oncology
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• v.6 no.1
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• pp.40-45
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• 1990

Thirty five lesions of 35 patients with locally advanced malignant tumors of head and neck were received thermoradiotherapy with ultrasound and/or 915 MHz microwave. Most of all patients were failed with previous conventional therapeutic trial. Hyperthermia had been done immediately after radiotherapy, twice a week, $43^{\circ}C$ for one hour and radiotherapy had been done 5 fractions per week with a fraction size of 2 Gy up to total 30 to 60 Gy. Conclusions are as follows; 1) Total response rate (CR+PR) of thermoradiotherapy with microwave and ultrasound was 80%. 2) Tumor depth, minimum temperature of tumor center, number of heat fraction and irradiation dose were statistically significant factors affecting response. 3) Hyperthermia with microwave and ultrasound can be used efficiently to control locally advanced malignant tumors in head and neck whether previously received near tolerance dose of radiotherapy or not.