Nasopharyngeal stenosis is defined as a morphological transition of narrowing at the nasopharyngeal region. A 2-yearold, castrated male, Korean short hair cat was referred to the animal medical center, Gyeongsang National University. According to clinical signs, diagnostic imaging, and physical examination, nasopharyngeal stenosis was diagnosed. The staphylectomy was performed using a CO2 laser, and there were not any post-operative complications. The patient was discharged in two days. This report describes the case of nasopharyngeal stenosis in cat and represents that laser ablation could be a good option for surgical management of the nasopharyngeal region with a low complication rate.

Most of the C-14 produced is in the organic form, generated as methane (14CH4), methanol (14CH3OH), formaldehyde (14CH2O), and formic acid (14CO2H2). When analyzing C-14, it is transformed into the form of 14CO2, and its concentration is determined using LSC. Typical examples include the wet oxidation method, the combustion or Pyrolysis. The wet oxidation method uses strong acids and involves repeated operations, which generates large amounts of acid waste and secondary radioactive waste. The combustion method uses high temperatures, which requires an oxygen device. Pyrolysis also requires high temperature in a vacuum and catalysts. Catalysts are expensive because they are platinum-based. To compensate for these shortcomings, a C-14 analysis method using UV irradiation was developed. In this study, 100 mL of distilled water mixed with formic acid (CO2H2), potassium persulfate (K2S2O8), and silver nitrate (AgNO3) was irradiated with a 320-390 nm UV lamp to conduct a CO2 production reaction experiment. The UV range was measured using a photometer (UV Power puck II). The beaker was made of quartz in 150 mL size with three inlets : a temperature measurement, a sample inlet, and a collection tube connector. We changed the UV lamp used from a 450 W halogen lamp to a 100 W LED, which has a lower temperature and is safer. As a result of the experiment, CO2 bubbles were generated in the collection tube, due to the UV irradiation react, which uses oxidizer and catalysts. The maximum temperature of the solution irradiated with the LED UV lamp was less than 56°C. It confirmed the rate of bubble generation changed depending on the lamp distance, the amount of sample, oxidizer, and catalyst. In an experiment to confirm the reaction caused by heat, it was found that although a reaction occurred due to heat, the reaction was significantly lower than when using a UV lamp. The reproducibility experiment was conducted three times in total under the same conditions. It showed the same pattern. In the future, we plan to select mock samples, collect 14CO2 in Carbo- Sorb, and analyze them using LSC. The results of this research will be used as a technology to recover C-14 more safely and efficiently and will also be used to expand its application to the treatment of other wastes such as waste liquid and waste resin through simulated samples.

The WRK (Waste Repository Korea bentonite) compacted bentonite medium has been considered as the appropriate buffer material in the Korean SNF (Spent nuclear fuel) repository site. In this study, hydraulic properties of the WRK compacted bentonite core (4.5 cm in diameter and 1.0 cm in length) as the buffer material were investigated in laboratory experiments. The porosity and the entry pressure of the water saturated core at different confining pressure conditions were measured. The average velocity of water flow in the WRK compacted bentonite core was calculated from results of the breakthrough curves of the CsI aqueous solution and the hydraulic conductivity of the core was also calculated from the continuous flow core experiments. Because various gases could be generated by continuous SNF fission, container corrosion and biochemical reactions in the repository site, the gas migration property in the WRK compacted bentonite core was also investigated in experiments. The gas permeability and the average of gas (H2) in the core at different water saturation conditions were measured. Laboratory experiments with the WRK Compacted bentonite core were performed under conditions simulating the DGR environment (confining pressure: 1.5- 20.0 MPa, injection pressure: 1.0-5.0 MPa, water saturation: 0-100%). The WRK Compacted bentonite core was saturated at various confining pressure conditions and the porosity ranged from 27.5% to 43.75% (average: 36.75%). The calculated hydraulic conductivity (K) of the core using experimental results was 8.69×10-11 cm/s. The gas permeability of the core when the water saturation 0~58 % was ranged of 19.81~3.43×10-16 m2, representing that the gas migration in the buffer depends directly on the water saturation degree of the buffer medium. The average gas velocity in the core at 58% of water saturation was 9.8×10-6 m/s, suggesting that the gas could migrate fast through the buffer medium in the SNF repository site. Identification of the hydraulic property for the buffer medium, acquired through these experimental measurements is very rare and is considered to have high academic values. Experimental results from this study were used as input parameter values for the numerical modeling to simulate the long-term gas migration in the buffer zone and to evaluate the feasibility of the buffer material, controlling the radionuclide-gas migration in the SNF repository site.

After the decision of the Wolsong unit 1 permanent shutdown (2019), spent fuel stored in the spent fuel bay (hereafter, SFB) should be transported to a dry storage facility (MACSTOR or Canister) in order to decommission Wolsong unit 1. Accordingly, KHNP has established a shipment schedule for damaged fuel of Wolsong Unit 1 and is trying to complete the shipment according to the schedule. Wolsong is equipped with transportation casks and dry storage facilities, but baskets need to be manufactured separately. In addition, license approval is required for baskets, transport cask, and dry storage facilities for legal grounds to contain, transport, and store damaged fuels. In this paper, the initial model, upgrade model, and automation model of encapsulation equipment planned to be introduced in Canada to handle PHWR’s damaged fuel were compared, and the optimal model was selected in consideration of KHNP’s planned spent fuel shipment schedule. The PHWR’s damaged fuel encapsulation system is a system developed the PHWR’s damaged spent fuel to be handled in the same way as the existing PHWR when storing it in the dry storage facility and loading a basket for capsulation into transport cask. At the Gentilly-2 nuclear power plant in Canada, a manually operated encapsulation system was used due to the low quantity of damaged fuel, which can be encapsulated two bundles a day, and this model is an initial model. In the case of Wolsong Unit 1, it has about 300 damaged fuels, so it takes about nine months to work when using the initial model. The upgrade model developed to improve work efficiency and reliability has increased work efficiency through some automation, but it would take about eight months to process the damaged spent fuels of Wolsong Unit 1, and this model has not yet been manufactured and applied. Lastly, the automation model changed the work location outside the SFB and automated drainage/drying operations. It is easy to maintain and replace consumables because the work is carried out by lifting the damaged fuel to a shuttle outside the SFB surrounded by a shielding chimney. Considering the reduction of drainage/drying time, it is possible to save about four times as much time as the initial model. That is, if the automation model is used, it is judged that the supply of Wolsong Unit 1 can be processed in about two months. However, in terms of license, initial model and upgrade model are expected to be easier and the period is expected to be shortened. However, if licensing is carried out as soon as equipment design is completed, it is believed that the period can be shortened by parallel equipment manufacturing and licensing. It is judged that the best way to comply with the target schedule is to select an automation model with excellent work performance, develop equipment, and proceed with licensing at the same time. Accordingly, KHNP is in the process of designing equipment with the aim of using the automation model to take out damaged fuel for Wolsong Unit 1.

Korea has an agreement for cooperation with 31 countries, including the United States, Canada, Australia, and Japan. Under the agreement, the obligated items must be used for peaceful purposes, comply with nuclear non-proliferation and international safeguards, and obtain prior consent of shipment in case of enrichment, reprocessing, retransfer. Among them, the United States, Canada, and Australia have signed Administrative Arrangements of Cooperation Agreements (Supplementary Arrangements in Canada) for the international transfer and annual reports of obligated items. When operators submit an annual report, the government compiles and make the annual report based on the data. Ideally, the final report is submitted by the operator should be the national annual report, but in practice, discrepancies occur between sum of the operator’s and goverment’s. In order to resolve these problems and strengthen the linkage between exports contrpol and safeguards, our institute has begun the project to develop an ‘Obligation Tracking System for internationally controlled items (OTS)’. It is believed that obligated items which are unnecessarily included or omitted in annual report could be managed properly by developing OTS for life cycle of the items such as import, disposal/ termination or transfer to other countries. In case of nuclear material, especially, the characteristics of the facilities (e.g., bulk-handling facilities) must be considered and principles of fungibility, equivalence, and proportionality should be applied to materials. In order to computerize these procedures, we would like to propose to adopt the format of Code 10 for obligated item management. Code 10 is the form of the annex to the Korea-IAEA safeguards agreement which includes all records of inventory changes, import/export, and domestic movement of nuclear materials. It is expected to minimize discrepancies between operators’ annual reporting data and national annual reporting and further contribute to enhancing national trust and nuclear transparency.

The striped fruit fly, Zeugodacus scutellata., is ubiquitous in agricultural areas, making it a critical pest to monitor and manage. It is necessary to develop a technique for rearing Z. scutellata in the laboratory to achieve mass production for biological control. The pumpkin is an important host plant for Z. scutellata; females lay their eggs on the tops of pumpkin flower buds, and larvae consume the stamens from top to bottom before dropping to the ground. Several types of diets are considered in the present study, including liquid, solid, and semisolid diets. Methyl benzoate, propionic acid, sodium benzoate, and citric acid were tested for their ability to suppress microbial contamination and improve the shelf life of diets. Fresh pumpkin, pumpkin flower, and pumpkin powder were used as primary ingredient. Reared adults were tested for their egg laying and survival abilities based on different diets. Approximately 86% of adults emerged from liquid and semisolid diets. Solid diets reduce pupae production and adult emergence. The diets with a total viability of less than 75% were discarded, which is considered as a reasonable threshold to determine whether a diet is nutritionally sufficient to rear the flies. Based on the results of the present study, we have developed a diet for mass rearing in laboratories, which may assist in providing a scientific basis for the effective control of Z. scutellata.

Sweet persimmons are valuable commodity in the export market. However, present of insect pest such as Asiacornococcus kaki can cause limit to many export markets. In this study, ethyl formate(EF), as alternative to methyl bromide(MB), was used in scale-up commercial trial(20ft reefer). Application of 50 g/m3 of EF for 6 hours at 5 ℃ showed proven efficacy against all developmental stages of A. kaki without LLDPE-packaging fruits and no phytotoxic damage on sweet persimmons. This study demonstrated that EF fumigation can be effectively control to target A. kaki before packaging with LLDPE-film of fruits.

As global warming and consumer’s preference for tropical/subtropical fruits increase, the number of orchards cultivating tropical/subtropical fruits in Korea is increasing. Accordingly, concerns about the introduction of exotic invasive pests that host tropical fruits. In this study, efficacy of ethyl formate(EF), as alternative to methyl bromide(MB), was evaluated. Commercial trial of EF was conducted in mango post-harvest storage conditions for controlling Scirtothrips dorsalis. Application of 10 g/m3 of EF for 4 hours at 10 ℃ showed proven efficacy on S. dorsalis without any phytotoxic damage on mango fruits in that condition.

Rotylenchus pini Mamiya, 1968 was reported from rhizospheric soils of Zoysia japonica in Korea. Females and males of the characterized population conform to the original species description from Japan and also to other subsequent species descriptions with variations in a few details in morphometrics including the existence of pharyngeal gland overlap in some specimen. Bayesian analysis of all the three DNA markers consistently grouped R. pini together with Rotylenchus species including R. zhongshanensis, a morphologically close species. Additionally, the newly obtained sequences of R. pini were found to be almost identical to the sequences assigned to Rotylenchus aff. devonensis in GenBank. These Rotylenchus aff. devonensis isolates might be representatives of R. pini populations. The current and previous phylogenetic studies supported by the recorded morphological plasticity within populations of the genus validate the proposed synonymy of Pararotylenchus with Rotylenchus.

최근 기후변화, 국제교역량, 여행객 및 외국 이주민 증가 등으로 고위험 식물병해충의 유입이 증가하고 있으 며, 고위험해충에 대한 국내 유입여부를 상시 조사하여 외래식물해충을 발견하고 발생시 조기 대응하는 전문지 식과 경력을 갖춘 민간 전문가를 활용한 예찰시스템 구축의 필요성이 요구되고 있다. 침입우려 고위험 해충인 오리엔탈과실파리(Bactrocera dorsalis)는 광식성 해충으로 파프리카, 망고, 바나나, 감귤류 등 약 80종의 과실 농작물에 피해를 입히고 있으며, 해당 종의 국내정착 시 큰 경제적 피해를 입을 것으로 예상된다. 2023년 조기 방제 및 선제적 대응과 국내 확산 정착을 방지하기 위해 4개도(강원, 전북, 전남, 경남) 18개 시군 90개소에 유인트 랩(스테이너)을 설치하여 설치장소별 월 1회 정밀조사를 실시하였다. 트랩에 포획된 해충을 수거 후, 동정한 결과 오리엔탈과실파리는 발견되지 않았다.