• Journal of radiological science and technology
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• v.31 no.4
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• pp.415-417
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• 2008

This study is to measure the radiation dose of neutrons generated by the particle accelerator during X-ray (photon) treatment with a neutron detection method by using CR-39, and to research how the generation of neutrons may incur problems associated with radiation doses for patient treatment when using high energy photons for cancer treatment as a clinical application. The findings are summarized as follows : The results showed that average 0.35mSv was measured with exposure of 1Gy photon in case of fast neutron, 0.65mSv with exposure of 2Gy photon, 1.82mSv exposure of 5Gy, 0.26mSv with exposure of 1Gy photon in case of thermal neutron, 0.56mSv with exposure of 2Gy photon, and 1.23mSv with exposure of 5Gy of photon. By measuring the occurrence of neutron by using Wedge Filter, it has been confirmed that the occurrence of neutrons increased when using Wedge Filter. The results also showed that more neutrons were detected over the existing experiments when using an SRS Cone requiring high doses of radiation. Total 2.85mSv neutrons were found on the average with exposure of 5Gy photon in case of fast neutron and 1.37mSv neutrons were found on the average with exposure of 5Gy photon in case of thermal neutron. During the general treatment, about 1.6 times more neutrons over 5Gy photon were found in case of fast neutron and about 1.12 time more neutrons over 5Gy photon were found in case of thermal neutron.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.1118-1123
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• 2009

Ten hospitals from the Gwangju area were used to examine shallow dose to eyes and thyroid from panoramagraphy. Thermoluminescent dosimeter (TLD) and Photoluminescent dosimeter (PLD) were used as measurement devices at each hospital. ICRP 60 and ICRP 73 set standards for acceptability for eyes at 15mSv and thyroid at 1mSv per year. Left eye measures with TLD and PLD resulted in 0.19mSv and 0.24mSv respectively. Right eye measures with TLD and PLD resulted in 0.23mSv and 0.25mSv respectively. Thyroid measures with TLD and PLD resulted in 0.08mSv and 0.25mSv respectively with both measures not exceeding standards for acceptance. There was a significant difference in comparing the left eye and thyroid for TLD and PLD (p<0.01). There was no significant difference with the right eye (p>0.05). The absorbed dose measurements for eyes and thyroid using TLD and PLD in regards to panorama devices at each hospital were within the ICRP 60 recommendations; however, with the possibility of stochastic effect, all dose levels were taken into consideration.

• Journal of dental hygiene science
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• v.15 no.3
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• pp.254-258
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• 2015

To compare the stationary dental X-ray generator and the portable dental X-ray generator and to understand spatial radiation dose depended on locations by measuring spatial radiation dose of the portable dental X-ray generator. The researchers used an Ionization chamber to measure spatial radiation dose which was generated while applying X-ray radiation to real bone skull phantom with both portable and stationary dental X-ray generator. There were 4 measurement locations which were immediate anterior, right, left and posterior. Distance of measurement was 50 cm in every location and the recorded result is an average of two applications of X-ray radiation to the maxillary molar area under the condition of 70 kVp, 3 mA, 0.1 sec. Average spatial radiation dose of portable X-ray generator was $37.51{\mu}Sv$, much higher than that of stationary X-ray generator which was $10.77{\mu}Sv$ (p<0.001). The result of the spatial radiation dose of the portable X-ray generator showed a huge difference depending on types of units which varied from $17.77{\mu}Sv$ to $68.90{\mu}Sv$ (p<0.05), also depending on the measurement location, immediate anterior resulted in the highest radiation dose of $54.14{\mu}Sv$ and immediate right was the lowest of $13.60{\mu}Sv$. Immediate left and posterior, however, resulted in similar radiation dose which were $42.12{\mu}Sv$, $40.18{\mu}Sv$ (p<0.01). With this result, we claim that usage of portable dental X-ray generator should be restricted to patients who can't move and exposure to radiation should be minimized by wearing lead-apron.

• The Korean Journal of Mycology
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• v.42 no.1
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• pp.64-68
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• 2014

Up to date several mycoviruses including Lentinula edodes Spherical Virus (LeSV) have been reported. As fungal virus was spreaded by infested hypae and spores it could be important to use virus-free spawns to eradicate the mushroom virus disease in the culture farm. We tested the imported spawns of Lentinula edodes by PCR whether LeSV was infested them or not. The primer set targeting the RdRp gene of LeSV was prepared based on partial sequence of the LeSV genome. The RT-PCR analysis showed that 87 among 88 imported spawns of L. edodes were infested by LeSV.

• Journal of radiological science and technology
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• v.20 no.1
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• pp.71-75
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• 1997

This study was Investigation that we will become aware of the scattering dose of duty station and TLD value of the radiation exposure by the radiation technologists based on the university hospital located in Kwang ju. The results are followings ; 1. The air of scattering dose in chest, when the number of objects are large, is 2.0 mR in P-A and 4.6 mR in Lat. at the back of X-ray tube 2. Radiologists, radiation exposure in duty station Is 0.22 mSv to 1.96 mSv in general examination, 0.22 mSv to 1.12 mSv in contrast and special examination, 0.26 mSv to 30.96 mSv in angiography, and 0.22 mSv to 0.40 mSv in C.T 3. The value of workig condition reveals 85.5% in general examination, 6% in contrast and special examination, and 5.8% in C.T. When the annual exposure is over 20 mSv, it must be measured again according to ICRP public 60.

• Korean Journal of Agricultural Science
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• v.42 no.4
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• pp.325-333
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• 2015

The ventilation systems composed three types of side vent (roll-up) 'SV', side vent+roof vent 'SV+RV', and side vent+roof fan 'SV+RF' with 7.5 m spacing, with specific set point temperatures for ventilation: SV ($35^{\circ}C$ open / $33^{\circ}C$ close), SV+RV or SV+RH ($35^{\circ}C$ open/$33^{\circ}C$ close for root ventilation and $37^{\circ}C$ open / $35^{\circ}C$ close for side vent). In the treatment of SV+RV, although the average daily maximum temperature inside the greenhouse temporarily increased by $38-40^{\circ}C$, thermal stress by high temperature did not occur and the disease incidence (%) of powdery mildew and downy mildew on the oriental melon were 25 - 75% lower than in the conventional SV treatment. In the SV treatment, the disease incidence (%) of powdery mildew and downy mildew were 1.4 - 7.7% and 4.2 - 15.9% for 'Deabakkul', and 20.3 - 22.8% and 2.8 - 11.3%, for 'Ildeungkkul'. The yield for one month was higher in the treatment of SV+RV than those in other treatments, with values of 2,105 kg/10a for 'Deabakkul' and 2,537 kg/10a for 'Ildeungkkul'. The simultaneous treatment with side vent and roof vent resulted in 16.2% higher yield (18.1% higher marketable yield) than that in the SV treatment for 'Deabakkul'.

• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.248-254
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• 2011

Biotransformation of pharmacologically inactive lactone prodrug simvastatin (SV) into pharmacologically active simvastatin ${\beta}$-hydroxy acid (SVA) exhibits inter-species differences due to variations in amount and activity of esterase enzymes. In this study, we investigated the pharmacokinetics (PK) of SV and its metabolite SVA following oral doses of SV from controlled-release (CR) tablets and immediate-release (IR) tablets in rodent and canine animal models that features different esterase activity. In rat PK study, no SV was detected in plasma for both formulations due to rapid hydrolysis of SV into SVA by plasma esterase. Besides, no significant differences in PK parameters of SV or SVA were observed between both species. In dog PK study, the relative oral bioavailability of CR tablets in terms of SV was 72.3% compared to IR tablets. Regarding formulation differences in dogs, CR tablets exhibited significantly lower $C_{max}$ (p<0.05), and higher $T_{max}$ (p<0.01) and MRT (p<0.01) for both SV and SVA compared to IR tablets. Accordingly, CR tablets of SV with prolonged drug release profiles in both species might be a potential candidate for a more effective delivery of SV with reduced side effects. Besides, similar PK parameters of SV and SVA in both species despite variation in enzyme activities suggested involvement of equally potent biotransformation pathways in these animal species.

• Korean Journal of Microbiology
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• v.14 no.3
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• pp.135-145
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• 1976

Confluent AGMK cells were infected by large plaque SV40 virus. Levels of DNA polymeras $({\alpha}\;and\;{\beta})$ were measured in the cytoplasm and the cell nucleus. The activities of DNA $polymerase-{\alpha}$ which found in both the cell nucleus and the cytoplasm were increased approximately eight folds at 48 hours after infection of SV40 virus. Only insignificant but constant amounts of DNA $polymerase-{\beta}$ were found either in the nucleus of the SV40 infected cell or of the uninfected cell. The characteristics of the SV40 virus induced DNA polymerases were compared with that of the uninfected cellular DNA polymerase in regard of the effects of pH, salt concentration, NEM concentration and temperature on those enzyme activities. No differential effect was found between both enzymes. Endouclease activities wre examined in the purified DNA $polymerase-{\alpha}\;and\;{\beta}$. The low level of endonuclease activity which might cut SV40 DNA 1 at one site was observed in the DNA $polymerase-{\alpha}$ whereas high but nonspecific endonuclease activities were found in the DNA $polymerase-{\beta}$.

• BMB Reports
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• v.42 no.1
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• pp.1-5
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• 2009

Synaptic vesicles (SVs) are key structures for synaptic transmission in neurons. Numerous membrane-associated proteins are sorted from the Golgi complex to the axon and the presynaptic terminal. Protein-protein and protein-lipid interactions are involved with SV targeting in neurons. Interestingly, many SV proteins have lipid binding capability, primarily with either cholesterol or phosphoinositides (PIs). As examples, the major SV protein synaptophysin can bind to cholesterol, a major lipid component in SVs, while several other SV proteins, including synaptotagmin, can bind to PIs. Thus, lipid-protein binding plays a key role for the SV targeting of synaptic proteins. In addition, numerous SV proteins can be palmitoylated. Palmitoylation is thought to be another synaptic targeting signal. Here, we briefly describe the relationship between lipid binding and SV targeting.

• Proceedings of the Korean Magnestics Society Conference
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• 2005.12a
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• pp.168-169
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• 2005