After the major radioactivation structures (RPV, Core, SG, etc.) due to neutron irradiation from the nuclear fuel in the reactor are permanently shut down, numerous nuclides that emit alpha-rays, beta-rays, gamma-rays, etc. exist within the radioactive structures. In this study, nuclides were selected to evaluate the source term for worker exposure management (external exposure) at the time of decommissioning. The selection of nuclides was derived by sequentially considering the four steps. In the first stage, the classification of isotopes of major nuclides generated from the radiation of fission products, neutron-radiated products, coolant-induced corrosion products, and other impurities was considered as a step to select evaluation nuclides in major primary system structures. As a second step, in order to select the major radionuclides to be considered at the time of decommissioning, it is necessary to select the nuclides considering their half-life. Considering this, nuclides that were less than 5 years after permanent suspension were excluded. As a third step, since the purpose of reducing worker exposure during decommissioning is significant, nuclides that emit gamma rays when decaying were selected. As a final step, it is a material made by radiation from the fuel rod of the reactor and is often a fission product found in the event of a Severe accident at a nuclear power plant, and is excluded from the nuclide for evaluation at the time of decommissioning is excluded. The final selected Co-60 is a nuclide that emits high-energy gamma rays and was classified as a major nuclide that affects the reduction of radiation exposure to decommissioning workers. In the future, based on the nuclide selection results derived from this study, we plan to study the evaluation of worker radiation exposure from crud to decommissioning workers by deriving evaluation results of crud and radioactive source terms within the reactor core.

n Korea, the decommissioning of nuclear power plants is being prepared, and a large amount of radioactive waste is expected to be generated. In particular, clearance level waste, which accounts for more than 90%, requires prevention of cross-contamination and prompt classification. In this study, the possible exposure route and the derivation of exposure dose for worker exposure management in a movable analysis system that can be analyzed onsite were studied. The movable radionuclide analysis system is divided into a preparatory room, a sample storage room, a radioanalysis room, a laboratory, and a waste storage room. It consists of one radioanalysis worker and one pre-treatment worker, and the main radiation exposure is expected to occur in the movement path in the sample storage room, radioanalysis room, and laboratory. The source term for the exposure evaluation, the annual usage dose presented in the radiation safety report in the movable radionuclide analysis system was used. The input data for the evaluation of the external exposure dose under normal circumstances (exposure situation, working hours, distance, etc.) is referenced at facility specifications. The internal exposure dose evaluation was assumed to be acute exposure (1 hour) assumed as internal pollution due to the drop in liquid sample during the pretreatment work. As an evaluation method, a method using a calculation formula and a method using an evaluation code was performed. For the evaluation of exposure dose using the calculation formula, a preliminary evaluation was performed using the point source method, the point kernel method, and intake and dose conversion factors. In addition, VISIPLAN and IMBA codes were used to evaluate exposure dose using the evaluation code, and the input data were supplemented for evaluation. As a result of the evaluation, the annual exposure dose limit of 20 mSv was satisfied for both normal and non-normal situations. In future research, it is planned to derive the evaluation results by particular scenarios for the detailed movement route and evaluation time according to the work process in the mobile radionuclide analysis.

The purpose of this study is to develop the analysis procedures for the evaluation of the structural integrity of the spent fuel in normal condition of transport at sea. Spent nuclear fuel must be transported from the wet storage facility in the nuclear power plant to the intermediate storage facility, and the structural integrity must be maintained in vibration and shock loads during the transportation. In general, the transport of spent nuclear fuel is performed in three kinds of modes: road, rail, and sea. During transport, the spent nuclear fuel is subjected to repeated vibration and shock loads by road surfaces, railroad tracks, and waves of the sea. It should be evaluated whether the structural integrity of the spent fuel is maintained under these load conditions. All nuclear power plants in Korea are located in coastal sites, and the interim storage facility for spent nuclear fuel is highly likely to be decided as a coastal site as well. Therefore, the main mode of the spent nuclear fuel transport is expected to be maritime transport by ships. In this study, the analysis procedure was developed to evaluate the safety of spent fuel at maritime transport by ships, and the procedure for evaluating the integrity of spent fuel under normal conditions of maritime transport were proposed. CFD analysis using SeaFEM was performed for the vibration analysis of the ship by waves, and the structural vibration analysis of the transport system was simulated using the developed in-house codes. The fatigue durability of the cladding was also evaluated using the developed fatigue analysis program and the fatigue analysis used the strain data obtained from the structural analysis. It was concluded that the value of the fatigue damage on the spent fuel cladding during normal conditions of maritime transportation is close to “0” and the structural integrity of the spent fuel is maintained in the same condition.

This study was performed to evaluate antimicrobial resistance of food-borne pathogens isolated from retail meat in Korea. A total of 157 samples of beef, pork, and chicken were collected and analyzed for E. coli, Salmonella, Campylobacter. Resistances to tetracycline were declined in accord with reduced usage of tetracycline in live stock production. E. coli stains from chicken meat had higher multi-drug resistance ratio than strains from other meat. One extended spectrum beta lactamase (ESBL) producing E. coli and two ESBL producing Salmonella were identified in this study. ESBL producing Salmonella strains were confirmed to carry CTX-M-1 type genes.

This study was performed to evaluate antimicrobial resistance of food-borne pathogens isolated from retail meat in Korea. A total of 157 samples of beef, pork, and chicken were collected and analyzed for E. coli, Salmonella, Campylobacter. Resistances to tetracycline were declined in accord with reduced usage of tetracycline in live stock production. E. coli stains from chicken meat had higher multi-drug resistance ratio than strains from other meat. One extended spectrum beta lactamase (ESBL) producing E. coli and two ESBL producing Salmonella were identified in this study. ESBL producing Salmonella strains were confirmed to carry CTX-M-1 type genes.

핵연료 운반용 실린더의 재사용을 위한 용기세척공장의 제염공정에 대한 성능을 평가하기 위하여 Na2CO3 + H2O2 혼합용액의 조합을 약간 달리한 2회의 시험을 실행하였다. 각 시험은 모두 일련의 5 단계에 걸쳐 실시되었다. 우라늄 제염의 주 화학종은 Na4UO2(CO3)3 로 식별되었다. 그리고 첫 단계에서의 세척액은 물이었으며, 이 단계에서 50% 이상의 우라늄이 제염되었다. 그 이후로는 단계가 더해 갈수록 우라늄의 제염양은 지수함수적으로 감소하는 경향을 나타내었으며, 화학양론적으로 제거된 우라늄에 비하여 투여된 Na2CO3 의 양은 과다함을 나타내었다. 이러한 결과들에 의하면, 공정최적화를 통하여 Na2CO3 의 투여량 감축, 세척폐액의 감량, 제염단계 축소 등을 꾀할 수 있을 것으로 판단된다.

Background : Tetraploid plants are bigger in the size of fruits, leaves, stems, and roots than diploid plants due to bigger cells attributed to chromosome multiplication. The advantage of tetraploid plants includes breakdown of self-incompatibility and increase of disease resistance. This study was carried out to gain tetraploid resources for breeding of new boxthorn varieties having pest resistance, higher yield, and self-compatibility. Methods and Results : Tetraploid lines and maternal varieties used in this study were C0148-10 and C0412-1 from Cheongyang-jaerae, M0148-94 and M0148-120 from Myongan, B0148-43 and B0148-78 from Bulro, D0148-62 and D0148-72 from Cheongdae, and Y0148-2 and Y0148-24 from Youngha. Betaine content was highest as 0.7 - 1.62% in leaf, followed by 0.55 - 1.17% in fruit and 0.04 - 0.23% in root. Betaine content in plant parts of several tetraploid lines increased compared to martenal varieties, higher in fruit for 5 lines including D0148-72, B0148-78, and C0142-1, higher in leaf for 5 lines including C0148-10, C0412-1, and M0148-94, and higher in root for 7 lines including Y0148-2, M0148-94, and M0148-120. Rutin content in leaf ranged 4.0 – 388.55 ㎎% and was highest as 388.55 ㎎% in Y0148-24. Tannin content in leaf of tetraploid lines was 4.70 - 6.12%, highest as 6.12% in Y0148-2 and M0148-120, similar to the maternal varieties. Youngha of the diploid plants showed the highest tannin content of 7.08%. Total free sugar content in tetraploid lines was higher as 8.53 - 12.53% than maternal varieties. Conclusion : Betaine and rutin contents increased in several tetraploid lines and Total free sugar content in tetraploid lines was higher as 8.53 - 12.53% than maternal varieties. This shows tetraploid boxthorn lines are very useful resources in breeding new varieties.

We experienced an 18-month-old patient with congenital lobar emphysema who underwent one-lung ventilation. With con-sideration that positive pressure ventilation could induce cardiopulmonary distress, induction was performed with spontane-ous breathing using sevoflurane without neuromuscular blocking agent. Bronchospasm occurred after intubation and posi-tion change, twice. He was relieved by administration of neuromuscular blocking agents. We discussed induction methods with minimal positive-pressure ventilation and the treatments for bronchospasm.

In treatment of right ventricular failure with pulmonary hypertension, milrinone has not only an inotropic effect but also a vasodilating effect, thus, recently, it has been widely used. Recent studies have reported on the direct stimulation effects of doxapram on the central nervous system. A 91-year-old female underwent hemiarthroplasty under spinal anesthesia. When transported to the recovery room, right ventricular failure, cardiogenic shock, and mental deepening occurred. After stabiliz-ing vital signs, milrinone, doxapram was administered. We report on the effective use of milrinone for acute right ventricular failure and the active use of doxapram for reduced consciousness and hypoventilation.

Chrysanthemum white rust, caused by Puccinia horiana, is one of the most destructive fungal diseases in chrysanthemum cultivation worldwide. For increasing efficiency of resistant breeding, molecular markers linked to chrysanthemum white rust resistance gene were developed in pseudo F1 cross population between ‘Puma White’ as susceptible and ‘Dancer’ as resistant using bulked segregant analysis (BSA). Of 280 RAPD primers (Operon 10 mer), 18 primers found to be polymorphic. After screening of these primers in 20 individual lines, only OPI-13520 was selected as closely linked marker to white rust disease resistance. Based on correspondence between phenotypic resistant level and marker in 187 segregation population, the genetic distance between white rust resistance gene and OPI-13520 marker assumed to be 3.8 cM. For OPI-13520 marker conversion into sequence characterized amplified region (SCAR) marker, the amplified fragment of OPI-13520 was purified, cloned and sequenced. Based on the DNA sequence of OPI-13520, SCAR maker was generated and verified in 20 individual lines used in BSA-RAPD.The results showed SCAR marker could be used to identify white rust resistance in chrysanthemum.