• Journal of Conservation Science
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• v.34 no.6
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• pp.539-548
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• 2018

This study was conducted to evaluate the effects of scattering radiation, which was not considered in the cultural Heritage radiography, by evaluating the relationship between the tube voltage (unit: kVp), film-floor-distance(FFD), and lead screen layout. The density (unit: D) of the test specimens and the scattered radiation increased with the tube voltage. The density of the test specimens showed an average deviation of 1.4 D; it was 0.17 D at 60 kVp, 1.54 D at 160 kVp, and 2.97 D at 220 kVp. The mean density of the scattered radiation was 0.10 D at 60 kVp, 0.40 D at 160 kVp, and 0.46 D at 220 kVp. The density tended to increase when the tube voltage ranged between 60 kVp and 160 kVp, as the FFD distance increased. However, a change in the permeation density was not observed for high voltages(160 kVp-220 kVp). Scattered radiation was observed when FFD was 50 mm, 100 mm, and 200 mm and no lead screen was used and the bottom surface was replaced with the lead screen. No scattered radiation was observed when FFD was 0 mm. The identification rate ranged from 2.08% to 2.67%, according to the FFD, for a 160 kVp tube voltage, and from 2.67% to 3.33% for a 220 kVp tube voltage.

• Journal of Life Science
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• v.20 no.8
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• pp.1181-1185
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• 2010

This study was carried out to evaluate the vaccination effects of recombinant fusion protein rVP19+28 against WSSV in shrimp, Litopenaeus vannamei. The VP19+28 gene fused with VP19 and VP28 genes was inserted into pET-28a(+) expression vector and cloned in E. coli BL21 (DE3) to produce fused gene product recombinant VP19+VP28 as a single protein. For the vaccination, the shrimps were fed with pellets coated with purified recombinant protein, rVP19+28, for 2 weeks. Then, constant amounts of WSSV at $1{\times}10^2$ diluted stocks were injected to the muscle of the shrimp for the in vivo challenge tests. Non-vaccinated shrimps showed a cumulative mortality of 100% at 11 days post-challenge. The shrimps vaccinated with the inactivated E. coli BL21 as a host cell control showed cumulative mortality of 100% at 17 days post-challenge. The shrimps vaccinated with rVP19, rVP28 and rVP19+28 showed mortalities of 66.7%, 41.7% and 41.7% at 21 days post-challenge, respectively. These results indicated that the rVP28 and rVP19+28 had relatively high vaccination effects against WSSV infection. However, this study suggests that the fusion protein rVP19+28 was more effective for the protection of shrimp against WSSV than rVP28, even though the cumulative mortalities were the same 21 days post-challenge.

• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.239-255
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• 1997

Expression of the cDNA of the VP1 gene on the genome RNA B segment of infectious pancreatic necrosis virus (IPNV) DRT strain in E. coli and a recombinant baculovirus were carried out. The VP1 gene in the pMal-pol clone (Lee et al. 1995) was cleaved with XbaI and transferred into baculovirus transfer vector, pBacPAK9 and it was named pBacVP1 clone. The VP1 gene in the pBacVP1 clone was double-digested with SacI and PstI and then inserted just behind T5 phage promoter and the $6{\times}His$ region of the pQE-3D expression vector, and it was called pQEVPl. Again, the $6{\times}$His-tagged VP1 DNA fragment in the pQEVP1 was cleaved with EcoRI and transferred into the VP1 site of the pBacVP1, resulting pBacHis-VP1 recombinant. The pBacHis-VP1 DNA was cotransfected with LacZ-Hyphantria cunea nuclear polyhedrosis virus (LacZ-HcNPV) DNA digested with Bsu361 onto S. frugiperda cells to make a recombinant virus. One VP1-gene inserted recombinant virus was selected by plaque assay. The recombinant virus was named VP1-HcNPV-1. The $6{\times}$His-tagged VP1 protein produced by the pQEVP1 was purified with Ni-NTA resin chromatography and analyzed by SDS-PAGE and Western blot analysis. The molecular weight of the VP1 protein was 94 kDa. The recombinant virus, VP1-HcNPV-1 did not form polyhedral inclusion bodies and expressed VP1 protein with 95 kDa in the infected S. frugiperda cells, which was detected by Western blot. The titer of the VP1-HcNPV-1 in the first infected cells was $2.0{\times}10^5\;pfu/ml$ at 7 days postinfection.

• Journal of fish pathology
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• v.28 no.2
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• pp.93-98
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• 2015

Full-length recombinant VP2 and VP3 proteins of aquabirnavirus isolated from olive flounder were expressed successfully in E. coli expression system. After rats were immunized with these proteins, antisera were used for in vitro and in vivo neutralization test. In in vitro test, VP2 antibody titers were higher than that of VP3. In in vivo assays, fish challenged with aquabirnavirus neutralized with VP2 antibody survived longer than other fish.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.355-363
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• 2015

Advancement in the medical field provides an opportunity for the development of medical equipment and also enable accurate diagnosis for the inspection and the treatment of diseases. The aging of equipment due to the frequent operation produce uncertainty in the patient exposure dose, so a quality control was implemented by establishing a safety management system on a regular basis. The x-ray tube voltage (kVp), which is directly involved in the patient exposure dose and the life of the equipment, needs periodic performance for the quality control, but it has a limitation due to the time and the cost. In this study, we proposed a new method for measuring the kVp with ease by using the Y and Cu to solve the problem of the time and cost. We also evaluated the usefulness and the effectiveness of the new method and its accuracy through the kVp measurement. After securing the condition, the amount of the tube current and evaluating the usefulness and effectiveness of kVp measured using Y and Cu. The density range used was at 0.5-1.0, kVp was in the range of ${\pm}10%$, then, we recorded the change in concentration as % of Y and Cu. This experiment showed that when Cu and Y was at 75 kVp, concentration was the same, and when the kVp was changed to 65 ~ 85 %, a gradual increase in concentration to 85 ~ 110 % was noted.

• The Journal of the Korea Contents Association
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• v.13 no.6
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• pp.331-338
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• 2013

CT for follow-up visits because of liver disease, body mass index (BMI) and kVp according to the change of the image quality and radiation dose to evaluate for changes. March 2010 to June 2011 at Pusan P University Hospital, abdominal CT scans a patient BMI (Body Mass Index. Less BMI) index was less than 25 in the treatment of subjects had a 48-person Noise and SNR at 100kVp abdominal image is lager than the 120kVp image. CTDI volume value at by the analysis of the radiation dose is 4.47mGy(100kVp) and 9.01mGy(120kVp). So CTDIvol in 100kVp is smaller than CTDIvol in 120kVp(decrease by 44.1%). And, effective dose is 7.1mSv(100kVp) and 12.51mSv(120kVp). So effective dose in 100kVp is smaller than effective dose in 120kVp(decrease by 43%). Evaluation of image quality is that Unacceptable 0 person, Suboptimal 0 person, Adequate 0 person, Good 1 person, Excellent 47 person. In case of repeatly patient, we examinate abdomianl CT scan by using low kVp and body mass index less than 25. We can has good quality image and benefit of low radiation dose.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.23-26
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• 1997

In exposuring x-rays, we can adjust three variables of kVp, mA and sec. The kVp is one of main factors affecting x-ray quality -peneterability. And miliampere-seconds is directly proportional to x-ray quantity. In this paper, we detected voltage variation of CdS, II-VI group semiconductor compounds, by kVp as the fundamental experiments of designing x-ray dosimeter. We exposured x-ray on the material from 40 to 100 kVp by increasing 2kVp using Shimadazu TH-500-125 Radio-Tex cx-s x-ray machine. We fixed miliampere -seconds to 100mA and 0.2 sec. After acquiring the raw data, we plotted the graph of kVp and voltage variation and figured slope value of 0.093 by regression. The standard deviation of voltage to kVp was 0.22. For the future study, the mAs variation study will be needed to investigate the connections between kVp and mAs in order to design x-ray dosimeter.

• Korean Journal of Veterinary Service
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• v.36 no.1
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• pp.23-30
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• 2013

An avian rotavirus (AvRV-2) was isolated from feces of broilers suffering from acute gastroenteritis in 2011. It was the first avian rotavirus isolated in Korea. To investigate the molecular characteristics of AvRV-2, the VP4, VP6, VP7 and NSP4 gene nucleotide sequences were determined and compared with those of rotavirus strains available in the GenBank database. The phylogenetic tree of VP7 gene showed that AvRV-2 had a high degree of nucleotide sequence homology (93.4% to 94.7%) with those of rotaviruses belonging to genotype G19 cluster. The phylogenetic tree of the VP4 gene revealed a high degree of nucleotide sequence homology (95.8% to 95.9%) with genotype P[30] rotaviruses isolated from chickens. The VP6 and NSP4 gene nucleotide sequences showed the highest identities with those of avian strains with 95.3% to 96.4% and 90.3% to 92.2%, respectively. Genetic characterization of the VP4, VP6, VP7 and NSP4 showed that AvRV-2 strain was most closely related to chicken rotavirus strains from Germany and Japan. Comparative nucleotide sequences and phylogenetic analysis indicated that avian rotavirus isolated from broilers belonged to genotype G19P[30] and it was the first report on avian rotavirus infection in Korea.

• Journal of the Korean Society of Radiology
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• v.12 no.2
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• pp.185-191
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• 2018

The purpose of this study was to evaluate the usefulness of BMI application to Urography CT by applying different tube voltages in accordance with body mass index. Group A (n = 38) with body mass index of lower than 25 was examined with tube voltage of 100 kVp while Group B (n = 45) with a BMI of 25 and higher was examined with tube voltage of 120 kVp. C group (n = 37) with body mass index (BMI) of lower than 25 was examined with tube voltage of 120kVp. Although the difference in average dose between group A (100 kVp) and group C (120 kVp) with low body mass index (BMI) of lower than 25 was $214.8mGy{\cdot}cm$, there was no significant difference in qualitative evaluation and, compared with patient group with body mass index of 25 and higher, results obtained were rather good. Therefore, this study verified that the tube voltage of lower than 100 kVp does not have adverse effect on the quality of image for patients with body mass index (BMI) of lower than 25.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.20 no.2
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• pp.253-264
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• 1990

The purpose of this study was to estimate the distribution of absorbed doses of each important organs of head and neck region in panoramic radiography. Radiation dosimetry at internal anatomic sites and skin surfaces of phantom (RT-210 Humanoid Head & Neck Section/sup R/) was performed with lithium fluoride (TLD-100/sup R/) thermoluminescent dosimeters according to change of kilovoltage (65kVp, 75kVp and 85kVp) with 4 miliamperage and 20 second exposure time. The results obtained were as follows; Radiation absorbed doses of internal anatomic sites were presented the highest doses of 1.04 mGy, 1.065 mGy and 2.09 mGy in nasopharynx, relatively high doses of 0.525 mGy, 0.59 mGy and 1.108 mGy in deep lobe of parotid gland, 0.481 mGy, 0.68 mGy and 1.191 mGy in submandibular gland. But there were comparatively low doses of 0.172 mGy and 0.128 mGy in eyes and thyroid gland that absorbed dose was estimated at 85kVp. Radiation absorbed doses of skin surfaces were presented the highest doses of 1. 263 mGy, 1.538 mGy and 2.952 mGy in back side of first cervical vertebra and relatively high doses of 0.267 mGy, 0.401 mGy and 0.481 mGy in parotid gland. But there were comparatively low doses of 0.057 mGy, 0.068 mGy and 0.081 mGy in philtrum and 0.059 mGy in middle portion of chin that absorbed dose was estimated at 85kVp. According to increase of kilovoltage, the radiation absorbed doses were increased 1.1 times when kilovolt age changes from 65kVp to 75kVp and 1.9 times when kilovolt age changes from 75kVp to 85kVp at internal anatomic sites. According to increase of kilovoltage, the radiation absorbed doses were increased 1.3 times when kilovolt age changes from 65kVp to 75kVp and 1.6 times when kilovoltage changes from 75kVp to 85kVp at skin surfaces.