The study of blowfly (Diptera, Calliphoridae) biodiversity and distribution is crucial for forensic investigations involving cadavers. Abiotic and biotic factors, such as seasonality and habitat type, have significant impacts on blowfly populations. However, few forensic entomology studies have been conducted in South Korea, particularly the Gyeongsangnam-do region. To address this, in this study, an extensive year-long survey was conducted to analyze the compositions, habitat preferences, distribution, and seasonal abundance of forensically relevant blowflies in urban and forested habitats in Gyeongsangnam-do, utilizing mouse carcass-baited traps set for 48 h each month. A total of 3,478 adult blowflies were recorded, encompassing six genera and 14 species, with a noted absence of specimens during the winter months. The predominant species was Lucilia porphyrina, accounting for 37.1% of the total sample, followed by Chrysomya pinguis (27.5%), Lucilia sericata (7.6%), and Lucilia illustris (7.1%). The species composition was consistent across all surveyed regions; however, seasonal variation in species diversity was evident, with a peak in spring and decline in summer. Notably, certain species exhibited clear preferences for either urban (Calliphora calliphoroides and L. sericata) or forested habitats (L. porphyrina and Ch. pinguis). This pioneering study elucidates the diverse blowfly communities in Gyeongsangnam-do, highlighting significant seasonal and habitat-dependent variations.

In this research, the marine medaka Oryzias javanicus underwent a 96 h exposure to two concentrations of the red tide dinoflagellate Karenia mikimotoi (1,000 and 5,000 cells mL-1), and the temporal variations in biochemical responses related to antioxidant and immunity parameters were assessed in the liver tissue. The study revealed a significant increase in ichthyotoxicity with elevated cell concentrations of K. mikimotoi, especially evident at 96 h in marine medaka exposed to 5,000 cells mL-1. At 1,000 cells mL-1 of K. mikimotoi, the opercular respiratory rate showed a significant increase, whereas exposure to 5,000 cells mL-1 resulted in a lowered rate. The intracellular malondialdehyde content was significantly elevated in response to both cell concentrations at 96 h. Regarding glutathione content, levels were significantly increased by exposure to both cell concentrations. Catalase and superoxide dismutase enzymatic activities experienced an increase at 1,000 cells mL-1 of K. mikimotoi, while their activities were reduced at 5,000 cells mL-1 at 96 h. The analysis of two immunity parameters, alternative complement pathway and lysozyme, demonstrated significantly reduced activities in the liver tissue exposed to 5,000 cells mL-1 of K. mikimotoi. These findings aim to enhance the understanding of K. mikimotoi toxicity in marine fish by offering insights into biochemical responses associated with harmful algal blooms.

Throughfall (TF)—as a diffusive hydrological water flux—significantly affects ecohydrological and biogeochemical processes within forest ecosystems. Recent investigations have revealed the impact on TF generation processes within unmanaged coniferous plantations of under-canopy structures, particularly those laden with dead branches, as well as upper-canopy structures. However, spatiotemporal variations in TF in such plantations remain unexplored. We investigated these variations in TF in a 33-year-old unmanaged Japanese cypress (Chamaecyparis obtusa Endl.) plantation, laden with dead branches, with a high stand density (SD) of 2,500 stems ha−1. Over a two-year period (May 2017 to May 2019), we conducted weekly TF measurements using 28 manual-type TF collectors. We compared the present TF ratio and canopy water storage capacity (S) with those of previous investigations conducted on Japanese cypress plantations. Moreover, we assessed key indices contributing to spatiotemporal TF variations (canopy cover: CC and distance to the nearest stem: TFd) and potentially influential dead branch indices (number of dead branches: TFdb and vertical spacing length on a stem: TFs) to elucidate TF spatial patterns. The results showed that the TF ratio was notably lower than that in previous studies (n = 13), with SD (r = –0.92, p < 0.001) and S (r = –0.87, p < 0.001) emerging as key influential factors among other stand-structure parameters. Spatial TF patterns exhibited a decreasing trend as the gross rainfall (GR) increased. Temporal stability was not significantly associated with CC (r = 0.120, p = 0.544), TFd (r = 0.068, p = 0.731), TFdb (r = 0.211, p = 0.281), or TFs (r = 0.206, p = 0.292) for any of the TF collectors. These findings underscore the important role of GR in determining the spatial variation of TF. Collectively, our results contribute to an enhanced understanding of TF spatiotemporal heterogeneity in unmanaged Japanese cypress plantations with dead branches.

The demand for transportation is increasing due to the continuous generation of radioactive wastes. Especially, considering the geographical characteristics of Korea and the location characteristics of nuclear facilities, the demand for maritime transportation is expected to increase. If a sinking accident happens during maritime transportation, radioactive materials can be released into the ocean from radioactive waste transportation containers. Radioactive materials can spread through the ocean currents and have radiological effects on humans. The effect on humans is proportional to the concentration of radioactive materials in the ocean compartment. In order to calculate the concentration of radioactive materials that constantly flow along the ocean current, it is necessary to divide the wide ocean into appropriate compartments and express the transfer processes of radioactive materials between the compartments. Accordingly, this study analyzed various ocean transfer evaluation methodologies of overseas maritime transportation risk codes. MARINRAD, POSEIDON, and LAMER codes were selected to analyze the maritime transfer evaluation methodology. MARINRAD divided the ocean into two types of compartments that water and sediment compartments. And it was assumed that radionuclides are transfered from water to water or from water to sediment. Advection, diffusion, and sedimentation were established as transfer process for radionuclides between compartments. MARINRAD use transfer parameters to evaluate transer processes by advection, diffusion, and sedimentation. Transfer parameters were affected by flow rate, sedimentation rate, sediment porosity, and etc. POSEIDON also divided the ocean into two types that water and sediment compartment, each compartments was detaily divided into three vertical sub-compartment. Advection, diffusion, resuspension, sedimentation, and bioturbation were established as transport processes for radionuclides between compartments. POSEIDON also used transfer parameters for evaluating advection, diffusion, resuspension, sedimentation, and bioturbation. Transfer parameters were affected by suspended sediment rates, sedimentation rates, vertical diffusion coefficients, bioturbation factors, porosity, and etc. LAMER only considered the water compartment. It divided the water compartment into vertical detailed compartments. Diffusion, advection and sedimentation were established as the nuclide transfer processes between the compartments. To evaluated the transfer processes of nuclides for diffusion and advection, LAMER calculated the probability with generating random position vectors for radionuclides’ locations rather than deterministic methods such as MARINRAD’s transfer parameters or POSEIDON’s transfer rates to evaluate transfer processes. The results of this study can be used as a basis for developing radioactive materials’ ocean transfer evaluation model.

Heavy water primary system decontamination technology is essential to reduce worker exposure and improve safety during maintenance and decommissioning of nuclear facilities. Advanced decontamination technology development aims to secure controlled decontamination technologies that can reduce the cost of radiation exposure and dramatically reduce the amount of secondary waste generated when decontaminating large equipment and large-area facilities. We conducted a study to identify candidate corrosion inhibitors through the literature and analyze the degree of corrosion of carbon steel samples. Countries with advanced nuclear technology have developed chemical decontamination technology for the entire nuclear power generation system and applied it to the dismantling and maintenance of nuclear power plants. In the decontamination process, the corrosion oxide film must be removed. If the base metal is corroded by the decontaminant in this process, additional secondary waste is generated and treatment costs increase. Therefore, it is necessary to develop a corrosion inhibitor that inhibits the corrosion of the carbon steel base metal in the decontamination process to generate a secondary waste liquid that is favorable for waste reduction and treatment. In this presentation, a study was conducted to analyze the extent of corrosion on a carbon steel base material and identify candidate materials for corrosion inhibition testing. Samples were analyzed using optical microscopy and EPMA analysis to determine the thickness of the corroded oxide film. EPMA analysis also allowed us to map the elemental distribution of the carbon steel corrosion layer, which we plan to quantify in the future. The candidate materials for organic-based corrosion inhibitor were also selected based on their inhibition mechanism; having high electronegative elements for coordinate covalent bonding at metal surface and hydrophobic nonpolar group for preventing access of corrosive substances.The selection of candidate materials for corrosion inhibition testing was based on the mechanism of the corrosion inhibitor. Organic-based corrosion inhibitors are adsorbed by donor-acceptor interactions between metal surfaces and highly electronegative elements. Corrosion can also be inhibited by arranging hydrophobic nonpolar groups on metal surfaces in the solution direction to prevent access of corrosive substances.

Despite its advantages such as safety, unnecessary pretreatment, and decontamination of waste with complex geometry, conventional ultrasonic decontamination technology has been only used to remove loose contaminants, oil and grease, not fixed contaminants due to the limitations in increasing the intensity in the high frequency range. Thus, ultrasound has been used as an auxiliary method to accelerate chemical decontamination of radioactive wastes or chemicals were added to the solution to increase the decontamination efficiency. The recently developed high-intensity focused ultrasound (HIFU) decontamination technology overcomes these limitations by combining multiple frequencies of ultrasonic waves in a specific arrangement, making it possible to remove most fixed contaminants, including radioactive micro particles less than 1 micrometer within half an hour. KEPCO NF and EnesG developed mobile HIFU decontamination equipment and successfully demonstrated the decontamination effect on various radionuclides found in nuclear power plants by treating radioactive metal waste to the level below free release criteria. The mobile HIFU decontamination equipment used in the demonstration can be operated anywhere where water is supplied, including controlled area in nuclear power plants, and is expected to be used widely for decontamination and free release of metal radioactive wastes.

The occurrence of shear failure in a rock mass, resulting from the sliding of joint surfaces, is primarily influenced by the surface roughness and contact area of these joints. Furthermore, since joints serve as crucial conduits for the movement of water, oil, gas, and thermal energy, the aperture and geometric complexity of these joints have a significant impact on the hydraulic properties of the rock mass. This renders them critical factors in related industries. Therefore, to gain insights into the mechanical and hydraulic behavior of a rock mass, it is essential to identify the key morphological characteristics of the joints mentioned above. In this study, we quantified the morphological characteristics of tensile fractures in granitic rocks using X-ray CT imaging. To accomplish this, we prepared a cylindrical sample of Hwang-Deung granite and conducted splitting tests to artificially create tensile fractures that closely resemble rough joint surfaces. Subsequently, we obtained 2D sliced X-ray CT images of the fractured sample with a pixel resolution of approximately 0.06 mm. By analyzing the differences in CT numbers of the rock components (e.g., fractures, voids, and rock matrix), we isolated and reconstructed the geometric information of the tensile fracture in three dimensions. Finally, we derived morphological characteristics, including surface roughness, contact area, aperture, and fracture volume, from the reconstructed fracture.

Most Small Modular Reactors currently under development are pursuing designs that can demonstrate flexibility in terms of construction and operation, and seeking to adopt innovative technologies to implement them, which is a very big challenge not only from the developer’s perspective but also from the regulator’s perspective. For the successful development of SMRs, it is necessary to move away from the existing prescriptive regulatory approach and exercise regulatory flexibility to sufficiently reflect design characteristics. The reason why SMR development is actively progressing around the world is to overcome the limitations of existing Light Water Reactors. Licensing advanced reactors such as MSR, VHTR, and microreactors requires a different approach from the existing conservative regulatory framework, taking into account changing regulatory environment. With the development of information technology and artificial intelligence, new types of threats are emerging, most of which are related to nuclear security. The IAEA, as well as leading countries such as the United States and Canada, require that safety, security, and safety measures be reflected in the early stages of design (Safety, Security, Safeguards by Design) and should be applied in the regulatory process. In addition, it is recommended to design a system that can achieve synergy effects by identifying in potential issues that may cause regulatory interference between safety and security (SSI, Safety-Security Interface). The competitiveness of SMR in the international market will be highly dependent on the degree to reflect the importing countries’ requirements. Since most SMRs currently under development do not have significant differences in safety goals, multi-purpose usability, etc., it is necessary to faithfully reflect the environmental factors necessary for SMR operation in the adopting country in the design. The major issues expected are mostly nuclear security-related rather than safety, and the physical characteristics of the site including the geopolitical conditions of the importing country must be taken into consideration. In this paper, the necessity of SMR nuclear security regulation and the way how to reflect the Security by Design on SMR will be presented.

The effect of the surrounding vegetation on the seed germination and growth of mountain-cultivated ginseng (MCG, Panax ginseng C.A. Meyer) was investigated. Seed germination rate and growth were tested for allelopathy effects on four forest tree species after treatment with fallen leaves and leaf extracts. In the case of soil treatment through fallen leaves and crushed leaves, the germination rate was lower in the Quercus myrsinifolia treatments, and the average germination time was slower when Chamaecyparis obtusa was treated. In the case of Pinus densiflora and Quercus variabilis, which are used in most of the MCG cultivation areas, they did not have a significant effect on seed germination. In the fallen leaves treatments, the stem showed a tendency to lengthen. The hot water extract treatment showed a higher germination percentage than the cold water extract treatment. The extract treatment showed a deficient germination percentage of some MCG seeds. However, in the case of the treatments except for this, the germination percentage was similar to that of the control treatment. However, the Mean Germination Time, germination rate, and germination value were faster and higher than the control treatment. As a result of calculating the allelopathic index (AI) of MCG according to the extract treatment of 4 species, most had a negative effect on germination, and P. densiflora and Q. variabilis extracts showed the most significant effect. The ginsenoside content was higher in the fallen leaves treatment than in the control. The above results will help select and manage MCG plantations.

The ectoparasitic mite, Varroa destructor is one of the most destructive pests of the honeybee (Apis mellifera) leading to the collapse honey bee colony in many regions of the world. RNA interference (RNAi) is a novel approach recently proposed for insect pest control. However, the efficiency of RNAi in insects is low due to the lack of effective delivery methods for dsRNA and sensitivity to nuclease degradation. Therefore, the success of RNAi technology largely depends on the stability of dsRNA. To explore the possibility of using RNAi to control varroa mite, we determined the effects of dsRNA targeting a subunit of the cytoplasmic coatomer protein complex B2, D, and E subunits on target gene expression for varroa mite. We observe that dsRNA ingested by bees is transferred to the varroa mite, resulting in knockdown of COPB2 expression. Furthermore, we demonstrate that chitosan nanoparticles-dsRNA complexes were more stable for 7 days in honeybee tissue fluids. The dsRNA-conjugated with chitosan was protected from degradation in hemolymph, fat body, and midgut extracts collected from the honeybee. These results possibly suggest that nanoparticles-dsRNA complexes might be horizontally transferred from treated honeybee to varroa mite, in which case the honeybees could serve as RNAi vectors. We confirmed, moreover, dsRNA fed nontarget insects, honeybee, were unaffected, and no toxicity was observed for honeybee. Overall, these data suggest that dsRNA-conjugated with chitosan help escape effectively from degradation by honeybee tissue fluids and could improve RNAi efficiency in varroa mite.