왕피천 수계 내 저서성 대형무척추동물의 군집구조 분석을 위해 총 5개 지점에서 2023년 총 4회(4월, 6월, 8월 11월) 조사를 실시하였다. 조사기간 중 저서성 대형무척추동물은 총 5문 7강 17목 77과 156종 17,179.1개체/㎡가 채집되었다. 수환경 변화에 민감한 E.P.T. 분류군은 전체 156종 중 91종이 출현하여, 전체 출현종의 58.3%를 차지 하였다. 섭식기능군(FFGs) 분석결과, 종 출현 양상은 육식성 포식자(Predator: P)가 51종(32.69%)으로, 개체 출현 양상은 주워먹는 무리(Gathering-collector: GC)가 6,867.2개체/㎡(39.97%)로 높은 비율로 출현하였다. 서식기능 군(FHGs) 분석결과, 붙는 무리(Clinger: CL)가 70종(44.87%), 12,720.6개체/㎡(74.04%)로 가장 높은 비율로 출현 하였다. 군집지수 분석결과, 우점도지수(DI) 0.43, 다양도지수(H′) 3.51, 풍부도지수(R1) 4.59 균등도지수(J′) 0.77 로 나타났다. 생물학적 수질 판정 지수(BMI) 분석결과, 평균 92.36(±0.83)으로 모든 지점에서 “매우 좋음”으로 판정되었다.

갈색거저리 유충의 사료인 밀기울은 대부분 수입에 의존하고 있는데 일부 국가의 식량 수출 중단 조치 등에 따른 국제 곡물가격 상승으로 밀기울 가격은 인상되고, 식용곤충 판매가격이 하락하면서 생산비 절감을 위한 사료 개발이 요구되고 있다. 농업부산물 3종을 50% 이상 급이하게 되면 유충 생육이 저하되었기 때문에 본 연구는 적정한 배합비율을 선정하기 위해 첨가사료 20, 30% 함량으로 밀기울과 혼합하여 사료를 급이하였을 때 갈색거 저리 유충의 생육 특성과 영양성분 변화에 대해 밀기울만 제공한 대조구와 비교하였다. 부산물 A와 B, C를 각각 30% 함유한 처리구에서 갈색거저리 유충 무게는 대조구와 차이가 없음을 확인하였다. 먹이소화율은 부산물B를 20% 함유한 처리구가 80.5%로 대조구에 비해 높았고, 부산물C 30% 처리구에서 72.6%로 가장 낮았다. 갈색거저 리 유충의 생육일수 100일 기준으로 부산물B 30% 처리구에서 용화율이 76.1%로 대조구보다 1.6배 높았으며, 부산물A 20% 처리구는 29.2%로 용화율이 가장 낮았다. 갈색거저리 유충의 조단백질 함량은 부산물 C 30% 처리 구에서 대조구보다 10.3% 증가하여 아미노산 분석을 진행한 결과 sarcosine과 ornithine이 2.5배 이상 증가하였다. 이를 통해 부산물 B나 C를 30% 함유한 사료를 급이하였을 때 사육 원가를 절감하여 유충을 생산할 수 있을 것으로 사료된다.

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.

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.

Iris laevigata, which belongs to the Iridaceae, is now designated as an “endangered” (EN) grade by Korea Forest Service because it does not have many natural sites known for its reckless development and damage to its natural habitats. This study was carried out to establish the propagation protocol from seed to restore the native habitat of the I. laevigata and to utilize it for ornamental purposes. Basically, the appearance and internal structure of seeds were observed and imbibition experiments were conducted. Germination rate was measured by cold stratification experiment, after warm followed by cold stratification experiment, and GA3 treatment experiment. The seeds had underdeveloped embryos, which had grown to about 25% of those of fully matured seed before germination. In the controlled laboratory experiment, after cold stratification at 5°C for 0, 4, 8, or 12 weeks, the seeds germinated to 0, 11.7, 43.4, or 51.7%, respectively, after 4 weeks of incubation at 25°C. After warm stratification (25°C, 8 weeks) followed by cold stratification for 0, 4, 8, or 12 weeks, the seeds germinated to 0, 51.7, 85.0, or 88.3%, respectively, after 4 weeks of incubation at 25°C. GA3 treatment did not overcome the dormancy. Our study determined the dormancy type of I. laevigata seed. Imbibition experiments showed that there was no physical dormancy, and it was also found that there was an underdeveloped embryo when it was observed that the embryo was growing according to the period of incubation. A nd t he e m bryo grew a t relatively w arm temperatures. It is concluded that the seeds of I. laevigata have morphophysiological dormancy (deep simple MPD). This is the first report to determine the dormancy type in seeds of this valuable ornamental plant.

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.