국내 중·저준위 방사성폐기물은 영구적 격리를 위해 처분장에 매립하고 있으며 그 위치는 경주에 있다. 이러한 방 사성폐기물의 영구적인 격리를 위한 처분시설은 공학적 방벽과 자연 방벽으로 구성되어 있으며 자연 방벽을 특성을 파악 하기 위하여 한국원자력환경공단에서는 2006년부터 부지특성조사를 수행하였고, 이후 부지감시 및 조사계획에 따른 감시 를 수행하여 부지특성의 변화를 지속적으로 확인하고 있다. 중저준위 방폐장의 수리지화학적 환경은 자연 방벽의 평가를 위해 중요한 요소로 손꼽히고 있으나 동해와 가까운 경주의 지역적 특성상 해수의 영향을 반드시 고려해야 한다. 따라서 본 연구에서는 처분 부지의 지하수 관정 7개 및 관정의 심도별 수질 자료를 취합해 지하수 자료 총 30개를 해수 2개소와 비교 분석하여 수리지화학적 환경을 해석하였다. 분석 자료는 수질 10개 항목(온도, EC, HCO3, Na, K, Ca, Mg, Cl, SO4, SiO2)을 2017년 3분기부터 2022년 3분기까지 총 5년간 20회의 자료를 활용하였다. 특히, EC, HCO3, Na, Cl의 농도 변화 를 통해 연구 지역의 배경 농도 및 관정의 구간별 해수의 영향을 파악하였으며, 시계열 군집 분석을 통해 담수, 기수, 해 수의 분류를 시도하였다. 그 결과, 기존의 모니터링 방법으로는 확인하지 못한 부지내 수리지화학적 변화를 제시하였다.

Cinnamaldehyde as the main component of Cinnamomum plants is well known as mammalian transient receptor potential ankyrin 1 (TRPA1) agonist, also activated by low temperature stimuli and mechanosensation. The other TRP subfamily, transient receptor potential vanilloid-1 (TRPV1) sensitive to pungent compounds such as capsaicin and allicin mediates the feeling of warmth. Both TRPA1 and TRPV1 channels are abundantly distributed in sensory neurons. Thus, there is possibility that these channels modulate repellent behaviors of mosquitoes and Drosophila through olfactory receptor neurons (ORNs). In order to confirm this hypothesis, we carried out laboratory repellent tests with cinnamaldehyde to Aedes aegypti females using arm-in-cage test and to a wild type and two TRP channel mutants Drosophila lines using a choice assay. Cinnamaldehyde showed strong repellency against Ae. aegypti and Drosophila wild adults at tested concentrations. However, a mutant fly line did not discriminate or detect the existence of the repellent. These behavioral data suggest that cinnamaldehyde may directly target the TRP channel. More studies to elucidate neural correlates of repellency to ainnamaldehyde compound are as follows: 1) Identifying the ORNs mediating cinnamaldehyde detection using single-sensillum recording techniques, 2) Co-localization of TRP genes on olfactory organs of Ae. aegypti and Drosophila using in situ hybridization and 3) Whether the Aedes TRP homologs might function in cinnamaldehyde repellency using rescued TRP chennels of Drosophila.

Although many synthetic pesticides have played important roles in pest management in agriculture, forest, housings, gardens, and managed landscapes for several decades, increased concerns to human health and environmental contamination have limited their usages and application in integrated pest management (IPM). Many plant essential oils have a variety of biological activities including adulticidal, acaricidal, larvicidal, ovicidal, repellent, antifeedant, and oviposition deterrent ones against insect pests. These oils and major terpenoid constituents show neurotoxic effects by interference with the cockroach octopamine and nematode SER-2 tyramine receptors. Most plant volatile oils contain plentiful phenylpropanoids, mono and sequiterpenes, and related phenols. They have been widely used in the flavor, fragrance, aroma therapy, food additives, and cosmetic industries. Some volatile plant essential oils have traditionally been used as stored product protectors and mosquito repellents, while their successful cases in commerce have been recently applied. Especially, these essential oils have not only been treated against house and garden pests, but these oils also have higher potential to be employed as “green pesticides” in the field of stored products, green house, and medical insect pests due to their fumigant action. Eventually, considering resistance development to many synthetic pesticides, it is likely that plant volatile or essential oil-based pesticides would play an essential role as an alternatives since they typically consist of the complex mixtures of constituents responsible for slow resistant development. In addition, the mixtures of these oils with conventional insecticides and the application of their capability to to enhance the efficacy of conventional products remains a main market niche. In this presentation, several cases of test evidences under laboratory and field conditions will be discussed. Ultimately, plant volatile-based pesticides and repellents would play an important role in future IPM programs due to their relative safety to non-target organisms and the environment.

Origanum essential oil [Origanum acutidens (Hand.-Mazz.)] showing insecticidal activity and repellency against red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae) adults was analysed by GC-MS. All constituents of the oil were identified, and the main components were carvacrol (67.2%), p-cymene (16.2%), γ-terpinene (5.5%), thymol (4.9%),and linalool(2.1%). In vapor phase fumigant assay, the origanum oil was more effective in closed condition (LD50 = 0.555 mg/cm3) than in open one (LD50 = 0.353 mg/cm3).This result suggests that the toxicity of the oil to red flour beetle is exerted largely by vapor phase. Based on 24-h LD50 values, the toxicity of caryophyllene oxide (0.00018 mg/cm3) was comparable with that of dichlorvos (0.00007mg/cm3) as a positive insecticide. In addition, thymol, camphene, α-pinene, p-cymene, and γ-terpinene gave good insecticidal activity (LD50 = 0.012 - 0.195 mg/cm3). In repellent test using 9 constituents of origanum oil, caryophyllene oxide showed 100% repellent activity at 0.0158 and 0.0032 mg/cm2. These results indicate that the origanum oil and its some components could be potential candidates as a fumigant and repellent for managing T. castaneum adults. Potential molecular target of repellents will be discussed.

CRISPR/Cas9-based genome editing technology fast replaces the previous methods that require protein engineering such as Zinc Finger Nucleases (ZFNs) and TALE nucleases (TALENs). Conventional genome editing of plant cells using CRISPR/Cas9 technology largely depends on Agrobacterium-mediated transformation of the plant cells and subsequent regeneration of whole plants from the edited cells. During this process, unwanted foreign DNAs including the antibiotics gene and fragments of the T-DNA can be introduced into plant genome. Insertion of these unwanted DNA causes lots of regulatory restrictions when commercializing the LMO products. To step aside these issues, we designed DNA-free ribonucleoprotein-based method and regenerated whole plants from the successfully engineered cells. We will share our discovery on the successful implement of this technology in lettuce protoplasts.

This study examined the physical and chemical properties of soil in Jang-San wetland in Busan Metropolitan City. The wetland covers wide and flat area comparing to its outside. The samples of the wetland soil were collected and analyzed in order to identify the profiles and chemical properties. According to the analyses of soil moisture and particle size distribution, the wetland soil mostly belongs to sandy loam with the soil moistures of 14.9-153.2%. The soil profiles are configured with O, A, B, and C horizons from the land surface. The organic matter content (2.38-16.7%) at most sampling locations decreases downwardly with the highest at 0-20 cm depth. The organic matter content has a good positive relationship with soil moisture content. According to X-ray diffraction analysis, the wetland soils contain quartz and feldspar (the main components of rhyolite porphyry) as well as montmorillonite, gibbsite, and kaolinite (the weathered products of feldspar). The wetland soil displays the highest iron concentration (average 22,052 mg/kg), indicating oxidation of iron. High concentrations of potassium (average 17,822 mg/kg) and sodium (average 5,394 mg/kg) originate from the weathering of feldspar. Among anions, sulfate concentration is highest with average 9.21 mg/kg that may originate from sulfate minerals and atmosphere.