가는잎향유[Elsholtzia angustifolia (Loes.) Kitag.]는 화형 이 아름답고, 정유 특유의 향기가 좋아서 분화용 및 지피용 관 상식물로 수요가 증가하고 있고, 전초에는 약효가 있다고 알 려져 있다. 본 연구는 가는잎향유의 육묘에 미치는 플러그 트 레이 셀 사이즈, 파종립수, 차광정도, 추비농도 등의 영향을 구명하기 위하여 수행되었다. 연구결과, 플러그 트레이 셀 사 이즈는 용량이 증가할수록 유묘의 초장, 엽수, 마디수, 근장, 지상부 생체중이 유의적으로 증가하였다. 파종 립수는 2립 파 종 시 가장 효율적이었고, 파종량이 증가할수록 생육이 감소 하였다. 차광정도가 높아질수록 초장은 증가하였고, 경직경, 엽수, 마디수는 55% 차광에서 가장 우수하였다. 추비 처리 시 공시비료 1000배 처리구에서 생육이 가장 양호하였다. 따라 서 가는잎향유의 육묘 시 162셀 트레이에 원예상토를 채운 다음 셀 당 2립 파종한 후 55% 차광막이 설치된 육묘상에서 공시비료 1000배로 엽면시비하는 것이 가장 효과적인 것으로 생각된다.

Background: Canine induced pluripotent stem cells (iPSCs) are an attractive source for veterinary regenerative medicine, disease modeling, and drug development. Here we used vitamin C (Vc) to improve the reprogramming efficiency of canine iPSCs, and its functions in the reprogramming process were elucidated. Methods: Retroviral transduction of Oct4, Sox2, Klf4, c-Myc (OSKM), and GFP was employed to induce reprogramming in canine fetal fibroblasts. Following transduction, the culture medium was subsequently replaced with ESC medium containing Vc to determine the effect on reprogramming activity. Results: The number of AP-positive iPSC colonies dramatically increased in culture conditions supplemented with Vc. Vc enhanced the efficacy of retrovirus transduction, which appears to be correlated with enhanced cell proliferation capacity. To confirm the characteristics of the Vc-treated iPSCs, the cells were cultured to passage 5, and pluripotency markers including Oct4, Sox2, Nanog, and Tra-1-60 were observed by immunocytochemistry. The expression of endogenous pluripotent genes (Oct4, Nanog, Rex1, and telomerase) were also verified by PCR. The complete silencing of exogenously transduced human OSKM factors was observed exclusively in canine iPSCs treated with Vc. Canine iPSCs treated with Vc are capable of forming embryoid bodies in vitro and have spontaneously differentiated into three germ layers. Conclusions: Our findings emphasize a straightforward method for enhancing the efficiency of canine iPSC generation and provide insight into the Vc effect on the reprogramming process.

KORAD (Korea Radioactive Waste Agency, http://www.korad.or.kr) has stored slightly contaminated ascon (asphalt coated concrete mixture) that was introduced to Gyeongju repository about a decade ago waiting for a final disposal. It is believed to be mainly contaminated by radioisotope 137Cs due to impurities introduced from the outside during the ascon manufacturing process. We studied characteristics of the radioactive waste to see whether this material would be proper enough to be disposed in Gyeongju LILW repository or be other ways to reduce the disposal volume including self-disposal before its final disposal otherwise. KORAD looked into the properness of characteristics of ascon in terms of WAC (Waste Acceptance Criteria) documented by KORAD that includes general chemical and physical properties of asphalt, density, size of grains, content of organic material and possibility of existence of chelate materials that qualitatively limited to be disposed by the criteria. And other associated characteristics such as gas generation and bio degradation were also investigated. Based on the data obtained from the study, we proposed various plausible solutions in associated with operational and disposal safety and economic view points. This study will be used for KORAD’s decision on how to control and safely dispose the spent ascon within a reasonable time period. And also those experiences may be applied for other LILW issues that require treatment or conditioning of radioactive wastes in the future.

최근 국내에서는 꿀벌 대량소실 현상이 2022년부터 전국적으로 발생하고 있다. 우리나라 뿐 만 아니라, 전세계 적으로 양봉산업에 큰 위협이 되고 있는 봉군붕괴현상은 2016년 미국에서 세계 최초로 보고되었다. 국내에서는 2022년 민관 합동조사 결과, 이상기온, 응애, 말벌 등이 주요 원인으로 지목되었다. 대량소실 현상을 보인 양봉농 가와 정상 농가의 병원체 검출 비교 결과, 유의성있게 검출이 증가되는 병원체는 발견되지 않았다. 그러나, Tyrophagus mite, Trypanosome, Lake Sinai virus, Apis mellifera filamentous virus 등의 신종 응애, 원충 및 바이러 스 감염이 추가로 확인되었다. 국내에서 새롭게 감염이 확인된 기생충과 병원체가 대량소실, 나아가 봉군붕괴현 상에 직간접적으로 영향을 주었을 것으로 사료되며, 지속적인 조사와 연구개발을 통해 기후등 환경변화에 따른 신종 질병 검색과 대책을 마련해야 할 것이다.

KAERI has been developing a new decontamination process that does not contain any organic chemicals in the decontamination solution and minimizes the use of ion exchange resin in the solution as a purifying step. The process is hydrazine based reductive metal ion decontamination for decommissioning (HyBRID) and consists of N2H4, H2SO4 and Cu+ ions. The primary system of the LWR is composed of materials with high corrosion resistance, such as stainless steel and Inconel, but among the materials, the feeder and header of the primary system of the PHWR are composed of carbon steel (SA106Gr.B) with low corrosion resistance. Therefore, when decontamination of PHWRs, attention should be paid to corrosion of carbon steel. Since Fe3O4, a contaminating oxide film formed on the surface of carbon steel dissolves faster than ferrite or chromite formed on the surface of Inconel or stainless steel, the base material is exposed to the solution and is corroded during decontamination. When a large amount of iron ions is eluted into the decontamination agent due to corrosion of carbon steel, not only the soundness of the base metal is adversely affected, but also the amount of decontamination waste increases. The purpose of this study is to develop inhibitors that can minimize corrosion of carbon steel when decontamination of PHWRs using the HyBRID decontamination process. CG, 570S and PP3 were selected as corrosion inhibitors. In addition, corrosion tests of carbon steel were conducted in the HyBRID solution with corrosion inhibitors. The best corrosion inhibitors and optimal operating conditions were selected, and HyBRID decontamination agents with corrosion inhibitors were much better in corrosion resistance than existing commercial decontamination agents.

The decommissioning of nuclear facilities produces various types of radiologically contaminated waste. In addition, dismantlement activities, including cutting, packing, and clean-up at the facility site, result in secondary radioactive waste such as filters, resin, plastic, and clothing. Determining of the radionuclide content of this waste is an important step for the determination of a suitable management strategy including classification and disposal. In this work, we radiochemically characterized the radionuclide activities of filters used during the decommissioning of Korea Research Reactors (KRRs) 1 and 2. The results indicate that the filter samples contained mainly 3H (500–3,600 Bq·g−1), 14C (7.5–29 Bq·g−1), 55Fe (1.1– 7.1 Bq·g−1), 59Ni (0.60–1.0 Bq·g−1), 60Co (0.74–70 Bq·g−1), 63Ni (0.60–94 Bq·g−1), 90Sr (0.25–5.0 Bq·g−1), 137Cs (0.64–8.7 Bq·g−1), and 152Eu (0.19–2.9) Bq·g−1. In addition, the gross alpha radioactivity of the samples was measured to be between 0.32–1.1 Bq·g−1. The radionuclide concentrations were below the concentration limit stated in the low- and intermediatelevel waste acceptance criteria of the Nuclear Safety and Security Commission, and used for the disposal of the KRRs waste drums to a repository site.

Glass wool, the primary material of insulation, is composed of glass fibers and is used to insulate the temperature of steam generators and pipes in nuclear power plants. Glass fiber is widely adopted as a substitute for asbestos classified as a carcinogen. The insulations used in nuclear power plants are classified as radioactive waste and most of the insulation is Very Low-Level Waste (VLLW). It is packaged in a 200 L drum the same as a Dry Active Waste (DAW). In the case of the insulations, it is packaged in a vinyl bag and then charged into the drum for securing additional safety because of the fine particle size of the fiberglass. A safety assessment of the disposal facility should be considered to dispose of radioactive waste. As a result of analyzing overseas Waste Acceptance Criteria (WAC), there is no case that has a separate limitation for glass fiber. Also, in order to confirm that glass fibers can be treated in the same manner as DAW, research related to the diffusion of glass fibers into the environment was conducted in this paper. It was confirmed that the glass fiber was precipitated due to the low flow velocity of groundwater in the Gyeongju radioactive waste repository and did not spread to the surrounding environment due to the effect of the engineering barrier. Therefore, the glass fiber has no special issue and can be treated in the same way as a DAW. In addition, it can be disposed of in the disposal facility by securing sufficient radiological safety as VLLW.

Sustainable capacity building of the rice value chain in Africa is essential in achieving the rice self-sufficiency and poverty alleviation. The breeding capacity enhancement has also been at the heart of AfricaRice’s mandate. Therefore, the Korea-Africa Food and Agriculture Cooperation Initiative (KAFACI) has concentrated breeding capacity enhancement for young breeders or breeding technicians of national research institutes in the KAFACI member countries. Four-month trainings have been conducted at the Regional Training Center located in Saint Louis, Senegal. The actual practice training is as follows; First is to learn practical skills and techniques of key aspects of rice breeding which are field preparation and layout, sowing, transplanting, fertilizer application, weed control, water management, hybridization/crossing, selection, yield and yield components determination, and rice palatability testing. Second is to learn some theoretical aspects of plant breeding through lectures including basic principles of breeding, evaluation for biotic and abiotic stresses, and statistical analysis. Third is to learn about the accurate use of field and lab equipment for rice breeding. Forth is to learn about proper scientific reporting and presentation. The courses were organized twice per year following two rice cultivation seasons in Senegal. From 2019, a total of 24 trainees participated in the 4 month courses. We believe they have acquired the basic knowledge and skills to implement rice breeding activities indpendently in their countries.

The Korea-Africa Food and Agriculture Cooperation Initiative (KAFACI) has been cooperating with AfricaRice since 2014 for the eradication of hunger and poverty in Africa through sustainable agriculture and its industrialization. At first, rice breeding activities for staple food production started with KAFACI member countries by sharing high-yielding Tongil-type rice breeding lines and varieties. The Africa Rice Development Partnership project entitled “Enhancement of high-yielding rice germplasm and breeding capacity of rice producing countries in Africa” is implemented for the period from 2016 to 2025 with three phases. The actual rice breeding activities have been conducted by applying anther culture haploid breeding technology in the laboratory and field of AfricaRice Saint-Louis center. The 1,547 elite lines selected through participatory variety selection were distributed to 21 national breeders of KAFACI member countries. These lines derived from the 1,181 cross combination and 34,616 breeding lines on Korea and AfricaRice germplasm crossed. Among them 11 new Tongil-type rice varieties have been selected and registered in the national variety catalogue of Senegal, Mali, Rwanda, Malawi, and Tanzania.

Safety for the radioactive waste disposed of in the disposal facility should be secured through safety assessment in consideration of the various situations. In this study, the influence and correlation of EDTA and ISA, which are the factors that can impede the safety of the disposal facility, were analyzed using the PHREEQC computational code. Thermodynamic database (TDB) of Andra, specific ion interaction theory (SIT) model as ionic strength correction model, radionuclides (Ni, Am, Pu) were adopted to perform the calculation on the distribution of chemical species by pH. According to the results, EDTA dominated the system and the effect of ISA is relatively small for the distribution of the chemical species of divalent and trivalent cations in neutral and weak base conditions. In the case of the tetravalent cations, the effect of ISA increased compared to the previous case especially in the strong base conditions. In conclusion, EDTA has a more significant effect on the system than ISA under the environment of the domestic disposal facility. Furthermore, when EDTA and ISA are present simultaneously in the system, the effects of two materials are inversely proportional and this characteristic should be considered during the safety assessment.

고령운전자의 인지 및 신체 기능 저하로 인한 교통사고 증가는 점점 심각한 사회적 문제가 되고 있으며, 이 로 인해 면허증을 자진하여 반납하는 제도가 운영되고 있으나 보다 객관적인 평가 방법이 필요하다. 본 연 구에서는 다양한 주행 상황에서 발생하는 정적 및 동적 시각 자극에 대하여 운전자의 시각적 행동을 평가 할 수 있는 운전 시뮬레이션 주행 환경과 시나리오를 구현하는 것이 목표이다. 이를 위해 고령운전자의 주 행 특성 분석에 활용된 운전 시뮬레이션 시나리오를 기존의 연구 문헌들로부터 수집하였고, 정적 및 동적으 로 구분된 표적 자극에 따른 텍스트 네트워크 분석을 통해 주행환경과 시나리오를 재분류하였다. 또한, 유 사한 유형의 시나리오들은 보다 발생 빈도가 높고 표적 자극이 다양한 주행환경으로 병합하였다. 연구 결과 로 신호교차로, 비신호 교차로, 왕복 2차로, 왕복 4차로 주행환경에서의 전체 12종의 시나리오로 구성된 운 전 시뮬레이션 콘텐츠가 구현되었다. 신호등, 정차된 차량, 표지판 등으로 구성된 정적 시각 자극과 주행 중 인 차량, 무단 횡단하는 보행자 등의 동적인 시각 자극이 제시되며, 이에 대한 시선 탐색(Visual Detection), 시지각(Visual Perception), 시각운동기능(Visuomotor Function)의 정량적 측정을 통해 운전자의 시각 행동 평가가 이루어진다. 본 연구에서 제안하는 시나리오 구성 방법은 운전 시뮬레이션 콘텐츠를 구현하기 위한 새로운 접근 방식으로써 시각 자극에 따른 운전 능력 검사 환경 구축에 관한 기초 자료로 활용될 수 있을 것으로 기대된다.

Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae is a highly contagious disease that leads to enormous economic losses in pig industry, worldwide. Of the many virulence factors produced by the causative bacterium, ApxA exotoxins have been considered as the most important contributor to the disease. The toxins are classified into four different types; ApxIA, ApxIIA, ApxIIIA and ApxIVA. Uniquely, ApxIVA is expressed across all serotypes of A. pleuropneumoniae only during in vivo infection in pigs. Active research focusing on resolving the precious roles and mechanisms of the toxins is still at its primitive stage. In this study, we report the development of monoclonal antibodies against the two major antigenic epitopes that were characterized in our previous study incorporating the in silico predictions and protein modeling analyses. Recombinant proteins of the selected epitopes were expressed and purified after molecular cloning of the corresponding partial genes in E. coli expression system. Subsequently, we generated hybridomas with lymphoid cells from the rats immunized with the recombinantly expressed proteins of Apx. Consequently, hybridomas exhibiting strong productivity of the monoclonal antibodies were selected for downstream verifications that tested for reactivity and specificity using Western blot and ELISA. Our results strongly suggest the potential application of the monoclonal antibodies developed in this study as useful reagents to further elaborate the mechanism of the A. pleuropneumoniae infection in pig.