• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2572-2577
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• 2023

A field determination method for small D-T neutron source yield based on the oxygen prompt gamma rays was established. A neutron-gamma transport equation of the determination device was developed. Two yield field determination devices with a thickness of 20 mm and 50 mm were made. The count rates of the oxygen prompt gamma rays were calculated using three energy spectra processing approaches, which were the characteristic peak of 6.13 MeV, the overlapping peak of 6.92 MeV and 7.12 MeV, and the total energy area. The R-square of the calibration curve is better than 94% and the maximum error of the yield test is 5.21%, demonstrating that it is feasible to measure the yield of D-T neutron source by oxygen prompt gamma rays. Additionally, the results meet the requirements for field determination of the conventional D-T neutron source yield.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.207-212
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• 2016

This work was carried out to investigate the ability of thirteen crossbreds for production of commercial chicken (CC) of Korean native chicken to be cut out for Korean circumstance. Total of one thousand three hundred of crossbreds were divided thirteen groups (100 birds/group) that were twelve groups (1A, 1B, 2A, 2B, 3A, 3B, 4A, 4B, 5A, 5B, 6A, 6B) to crossbreed with two sires (A, B) and six dams (1, 2, 3, 4, 5, 6) of parent stock (PS) of Korean native chicken and one group (HH) as commercial Korean native chicken. Experimental diets were starter diet (0~7d; CP 22.0% ME 3,150 kcal/kg), early diet (8d~Wt 800 g; CP 19.0% ME 3,150 kcal/kg) and finished diet (Wt 800 g~12 wk; CP 18.0% ME 3,150 kcal/kg). Fertility of 1B group was higher than other groups. Hatchability per fertilization eggs and hatchability per setting eggs were 87.5~89% and 87.9~96.3%, respectively, and those of 4B and 6B groups were lower compared to other groups. Weekly body weight of HH group was lower than other groups. CV values of body weight of thirteen groups were showed over 12% as 12.5~18.2%, and especially, those of 2B, 3B, 5B, HH groups were lower compared to other groups. Weekly feed conversion ratios (FCRs) of 13 crossbreds were 1.7~2.3, 2.1~2.5, 2.4~2.7 and 2.7~3.2 at the age of 6, 8, 10 and 12 weeks, respectively. Weekly production indexes of 2A, 3A and HH groups were the lower than other groups and those of thirteen groups decreased following weeks. Feed costs per body weight gain (kg) were 1,069~1,255 won, 1,100~1,263 won, and 1.468~1,696 won at starter, earlier and finished period of broilers. These results leaded down to conclusion to be possible selection of new Korean native commercial chicken that have the excellent performance and economics.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.5
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• pp.297-304
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• 2015

A multilayer gaseous detector has been developed for fast dose-verification measurements of raster-scan-mode therapeutic beams in particle therapy. The detector, which was constructed with eight thin parallel-plate ionization chambers (PPICs) and polymethyl methacrylate (PMMA) absorber plates, is closely tissue-equivalent in a beam's eye view. The gas-electron signals, collected on the strips and pad arrays of each PPIC, were amplified and processed with a continuous charge.integration mode. The detector was tested with 190-MeV raster-scan-mode beams that were provided by the Proton Therapy Facility at Samsung Medical Center, Seoul, South Korea. The detector responses of the PPICs for a 190-MeV raster-scan-mode proton beam agreed well with the dose data, measured using a 2D ionization chamber array (Octavius model, PTW). Furthermore, in this study it was confirmed that the detector simultaneously tracked the doses induced at the PPICs by the fast-oscillating beam, with a scanning speed of 2 m s-1. Thus, it is anticipated that the present detector, composed of thin PPICs and operating in charge.integration mode, will allow medical scientists to perform reliable fast dose-verification measurements for typical dynamic mode therapeutic beams.

• Natural Product Sciences
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• v.4 no.2
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• pp.100-104
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• 1998

The antimutagenic activity of a methanol extract of roasted Cassia tora seed against aflatoxin $B_1(AFB_1)$ was demonstrated with the Salmonella typhimurium assay. The numbers of revertants per plate decreased significantly when this extract was added to the assay system using Salmonella typhimurium TA100 and or TA98. The MeOH extract was then sequentially partitioned with $CH_2Cl_2$, EtOAc, n-BuOH, and $H_2O$. The $CH_2Cl_2$ and n-BuOH fractions possessed antimutagenic activity, but the EtOAc and $H_2O$ fractions were inactive. Both the MeOH extract and its fractions were capable of inhibiting the indirect-acting mutagen $AFB_1$, suggesting that these fractions may prevent the metabolic activation of $AFB_1$, or scavenge the electrophilic intermediate capable of inducing mutations. Column chromatography using silica gel yielded pure alaternin from the $CH_2Cl_2$ a fraction, and adenosine and isorubrofusarin gentiobioside from the n-BuOH fraction. Alaternin and isorubrofusarin gentiobioside demonstrated significant antimutagenic activities.

• Ocean and Polar Research
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• v.29 no.2
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• pp.187-191
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• 2007

In this study, antioxidant activities of acetone/dichloromethane and methanol extracts of Arctic seaweeds were investigated. The antioxidant properties of both extracts of arctic seaweed were evaluated using two different peroxynitrite tests, including scavenging power on authentic peroxynitrite and inhibitory activities on peroxynitrite generation from 3-morpholinosydnonimine (SIN-1) producing superoxide anion and nitric oxide simultaneously in vitro. At concentration of $10\;{\mu}g/ml$, the acetone/dichloromethane and methanol extracts of Odonthalia dentata exhibited 54.6 and 64.2% inhibition against peroxynitrite generation from SIN-1 while they exhibited 24.3 and 23.0% scavenging activities on authentic peroxynitrite, respectively. On the other hand, the acetone/dichloromethane extract of Polysiphonia stricta exhibited 61.8% inhibition only against the induced peroxynitrite from SIN-1. Furthermore, the crude extracts of Odonthalia dentata and Polysiphonia stricta were fractionated into n-hexane, 85% aq. MeOH, n-BuOH, and $H_2O$ fractions, successively, and only 85% aq. MeOH fraction exhibited the best inhibition.

• Korean Journal of Pharmacognosy
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• v.39 no.1
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• pp.60-67
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• 2008

The subcronic toxicity of BDR-29, a herbal preparation of Cassiae Semen, Prunellae Spica, Tribuli Fructus, and Uncariae Rhamulus et Uncus, was examined in male and female Sprague-Dawley rats. Rats were treated with the test substance at a dose 5 mg/kg, 50 mg/kg and 500 mg/kg intragastrically for 13 weeks. No death and abnormal clinical signs were observed throughout the administration period. There were not significantly different from control group in net body weight gain, food and water consumption, organ weight, gross pathological findings, and urine analysis among the groups rats treated with different doses of the BDR-29. Hematological findings and biochemical examination revealed no evidence of specific toxicity related to BDR-29. From these results, no observation effect level (NOEL) of BDR-29 is 500 mg/kg/day under the condition employed in this study.

• Korean Journal of Veterinary Research
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• v.22 no.2
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• pp.161-165
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• 1982

Biochemical and antimicrobial susceptibility tests were conducted on 40 strains of Pseudomonas aeruginosa originated from diseased chicken submitted for diagnosis to this Institute during 1978-80. An extensive study of the biochemical properties revealed that the tested strains can be identified with Pseudomonas aeruginosa. Antibiogram showed that all the strains were susceptible to gentamicin, colistin and amikacin but resist to nitrofurantoin, trimethoprim+sulfamethoxazole, ampicillin, methicillin and kanamycin, and had varing degreed of resistance to other antimicrobials including carbenicillin, sulfomamides, neomycin, streptomycin, tetracycline and chloramphenicol. Three of the most frequent resitance patterns observed were FM SXT AM ME KM CM TC SM NE SSS Pattern, FM SXT AM ME KM CM TC SM NE SSS CB Pattern and FM SXT AM EKM CM TC SM Pattern, and these resistance patterns contained 72.5% of the tested strains.

• Nuclear Engineering and Technology
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• v.46 no.2
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• pp.247-254
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• 2014

A study on the superconducting RF linac is underway in order to increase the beam energy up to 1 GeV by extending the Proton Engineering Frontier Project (PEFP) 100-MeV linac. The operating frequency of the PEFP superconducting linac (SCL) is 700 MHz, which is determined by the fact that the frequency of the existing normal conducting linac is 350 MHz. A preliminary study on the beam dynamics showed that two types of cavities with geometrical betas of 0.50 and 0.74 could cover the entire energy range from 100 MeV to 1 GeV. An inductive output tube (IOT) based RF system is under consideration as a high-power RF source for the SCL due to its low operating voltage and high efficiency. As a prototyping activity for a reduced beta cavity, a five-cell cavity with a geometrical beta of 0.42 was designed and fabricated. A vertical test of the prototype cavity at low temperatures was performed to check the performance of the cavity. The design study and the prototyping activity for the PEFP SCL will be presented in this paper.

• Korean Journal of Veterinary Research
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• v.39 no.6
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• pp.1099-1105
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• 1999

Reproductive failures, such as abortions were occured among dogs in a large kennel in Chonnam area April in 1994. After an initial positive result by the 2 mercaptoethal rapid slide agglutination test(2ME-RSAT) to Brucella canis on five sera, additional specimens from all dogs in the population were tested. The blood cultures and 3 following serological tests (2ME-RSAT, TAT, AGID) performed on all samples on the basis of surveys, the following results were obtained. 1. Thirty three of 62 dogs were seropositive. 2. Twenty blood samples from 33 dogs were cultured, all of the isolates were identified as B canis. 3. Although there was not siginificant difference in sex, age and breed of the cause brucellosis dectected, abortions was occured late in gestation stage.

• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.290-296
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• 2021

The purpose of this study was to examine the perceived emotion of music according to cognitive styles of music listening. A total of 91 music-related graduate students participated in this study. They were given a questionnaire about perceived emotions of music, musical elements, and Music Empathizing-Music Systemizing Inventory. To analyze statistically, Descriptive statistics, paired t-test, ANalysis Of VAriance (ANOVA), multi-variate analysis, and Pearson correlation analysis were conducted. Results showed that participants had relatively universal experience in perceived emotions of both types of music, and also showed that musical elements contributed to the experience differed by cognitive styles of music listening.