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        검색결과 585

        1.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Bangladeshi medicinal plants (BMP) have a history of traditional use in treating chronic inflammatory diseases, but a BMP bark’s antioxidant and anti-inflammatory effects remain largely unexplored. This study assessed methanolic extracts’ antioxidant and anti-inflammatory properties from the bark of 15 medicinal plant species native to Bangladesh. The methanol extracts of BMP bark were evaluated for their total antioxidant activity and ability to counteract inflammation induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages. Among the 15 bark extracts from BMP, Albizia odoratissima (A. odoratissima), Engelhardia spicata (E. spicata), and Shorea robusta (S. robusta) showed the highest total phenolic contents and total antioxidant capacity by effectively scavenging free radicals. In particular, these three bark extracts significantly reduced the mRNA expression of LPS-induced inflammatory cytokines and enzymes inducible by inflammation in macrophages. Also, the mRNA expression of NADPH oxidase 2 was significantly suppressed by the three bark extracts in LPS-induced RAW 264.7 macrophages. These results suggest that out of the 15 bark extracts obtained from medicinal plants in Bangladesh, the extracts from A. odoratissima, E. spicata, and S. robusta exhibit substantial total antioxidant capacity by efficiently scavenging free radicals and also inhibit LPS-induced inflammation in macrophages.
        4,000원
        8.
        2023.11 구독 인증기관·개인회원 무료
        In the decommissioning process of nuclear power plants, Ni-59, Ni-63 and Fe-55 present in radioactive waste are crucial radionuclides used as fundamental indicators in determining waste treatment methods. However, due to their low-energy emissions, the chemical separation of these two radionuclides is essential compared to others. Therefore, this study aims to evaluate the suitability of various pre-treatment methods for decommissioning waste materials by conducting characteristic assessments at each chemical separation stage. The goal is to find the most optimized pre-treatment method for the analysis of Ni-59, Ni-63 and Fe-55 in decommissioning waste. The comparative evaluation results confirm that the chemical separation procedures for Fe and Ni are very stable in terms of stepwise recovery rates and the removal of interfering radionuclides. However, decommissioning waste materials, which mainly consist of concrete, metals, etc., possess unique properties, and a significant portion may be low-radioactivity waste suitable for on-site disposal. Considering that the chemical behavior and reaction characteristics may vary at each chemical separation stage depending on the matrix properties of the materials, it is considered necessary to apply cascading chemical separation or develop and apply individual chemical separation methods. This should be done by verifying and validating their effectiveness on actual decommissioning waste materials.
        9.
        2023.11 구독 인증기관·개인회원 무료
        The nuclear power plant (NPP) decommissioning market is expected to expand not only domestically but also overseas. Proven technologies must be applied to decommission NPP. This is based on Article 41-2, Paragraph 2 of the domestic ‘Enforcement Decree Of The Nuclear Safety Act’. Proven technology refers to technology that has verified that it can be applied in the field through demonstration. In other words, in order to carry out NPP decommissioning, verification must be done. Demonstration refers to reducing technological uncertainty and directly verifying services implemented in the field. From a technology commercialization perspective, demonstration requires an approach based on technology readiness level (TRL) from a technology perspective and market readiness level (MRL) from a market perspective. The characteristics of demonstration also differ depending on the characteristics of each field. The demonstration in the field of nuclear energy is the demonstration of demand matching. This is to confirm the feasibility of the technology in the company’s required environment. In order to perform demonstration, a scenario must be derived by reflecting demonstration design considerations. After evaluating the derived scenario, an actual assessment is conducted using lab-based demonstration/virtual environment demonstration/real environment demonstration. What must be preceded by an actual assessment is confirming the consumer’s requirements. In this study, the necessary environment and requirements of consumer’s to perform NPP decommissioning were reviewed. The domestic decommissioning procedure requirements management system presents decommissioning procedures, potential worker accidents, and worker requirements. In the case of foreign countries, it was confirmed that complex wide need, cost benefit, risk reduction, waste generation, operation, reliability and maintenance (RAM) improvement and quantitative measures were evaluated for the technology to be demonstrated. Also the requirements for demonstrating decommissioning need to a detailed review of actual decommissioning cases. Therefore, a comparison must be made between the requirements based on actual NPP decommissioning cases and the requirements derived from this research process. Afterwards, the empirical research approach proposed by the Ministry of Trade, Industry and Energy was applied. The empirical research approach proposed by the Ministry of Trade, Industry and Energy is to secure a track record over a certain period of time and performance under conditions similar to the actual environment in the final research stage at the TRL level 6 to 8. Through this, it will be possible to confirm the suitability of overseas technology for domestic application.
        10.
        2023.11 구독 인증기관·개인회원 무료
        The presence of organic components in spent scintillation liquid should be considered during all steps of radioactive waste processing for final disposal. Scintillation liquids often referred to as cocktails are generated form radiochemical analyses of radionuclides, which mainly consists of mixtures of liquid organic materials such as toluene and xylene. Typical features of these liquid organic materials are volatility, combustibility and toxicity. These are the reason why special attention must be paid to the management of liquid organic radioactive wastes. To select an appropriate waste management strategy and to design the treatment process of spent scintillation cocktails, it is required to investigate the nature of the waste such as specific radioactivity and moisture content. The analysis results of spent scintillation liquid generated at Wolsong nuclear power plants will be discussed. An overview of the technical approaches available for the treatment of organic radioactive waste will be additionally provided.
        11.
        2023.11 구독 인증기관·개인회원 무료
        The PRIDE scale mechanical decladder is decladding apparatus for separating and recovering fuel material and cladding hull by horizontally slitting rod-cut. In order to enhance mechanical decladdng efficiency, the main requirements were considered as follows. Decladding of the fuel rods may be performed by rotation of three circular cutting blades inserted among the rollers arranged at 120° portion. In a mechanical decladder, a slitting assembly as a unit for slitting the cladding tube may include cutting blades for slitting and rollers for guiding extrusion of the cladding tube. Rotation of the cutting blades may be caused by the fuel rods being extruded from a plurality of rollers. Slitting intervals of rod-cuts having different diameters may be controlled by adding or removing a spacing plate between the cutting blade and a ranch bolt for fixing the slitting blade to the slitting assembly. An extrusion velocity with respect to the fuel rods may be controlled by a hydraulic pressure applied to the fuel rods. A force for cutting the fuel rods may be adjusted by controlling steel plates. Forces applied to a plurality of rollers may be generated by the hydraulic cylinder. The hydraulic pressure may be controlled by hydraulic pressure controller. The PRIDE scale mechanical decladder mainly consists of auto feeding module, hydraulic cylinder module and blade module. A load cell was installed between the hydraulic cylinder and the extrusion pin to measure the decladding force and slitting velocity, and a data acquisition system capable of obtaining data by using the RSC 232 was constructed. Also, the control panel can control the forward and backward movement of the extrusion pin, the hydraulic flow rate, and the hydraulic velocity. In the mechanical decladding test, 40 pieces of simulated rod-cuts were loaded in two auto feeding basket and slit by utilizing the 3-CUT blade modules in the housing, and hulls and simulated pellets were collected in the collection container. As a result, 80 pieces of simulated rodcut (brass pellets + Zry4 tube) were slit continuously without any problem. About 35 min was required to slit 80 rod-cuts and average decladding force was 260 kg. The decladding force of the ceramic simulated rod-cuts (castable) requires 25 kg less force than the brass pellets. Therefore, it is estimated that the spent fuel rod-cut can be fully split into three pieces using the mechanical decladder.
        12.
        2023.10 구독 인증기관·개인회원 무료
        In this study, Bacillus velesensis TJS119, isolated from freshwater, demonstrated growth inhibition against insect pathogenic fungi. The culture medium of the B. velezensis TJS119 strain underwent sequential fractionation with n-hexane, chloroform, ethyl acetate, n-butanol, and water. Notably, the n-butanol fraction exhibited significant antifungal activity against Metarhizium anisopliae and Beauveria bassiana. LC/MS analysis of antifungal peaks identified the production of various lipopeptides by B. velezensis TJS119, including two types of iturin A (C14, C15), four types of fengycin A (C14, C15, C16, C17), and two types of fengycin B (C16, C17). The antifungal efficacy of Iturin A and Fengycin against insect pathogenic fungi was further validated using the paper disc diffusion method. These findings underscore the potential of B. velezensis TJS119 as a promising candidate for future research and applications in the realm of agricultural biological controls against fungal diseases.
        13.
        2023.10 구독 인증기관·개인회원 무료
        Protaetia brevitarsis seulensis larvae from industrial insects are traditionally recognized as functional health foods in South Korea. We evaluated the immuno-modulatory effects of feeding beneficial microorganism (Bacillus velezensis TJS119) to P. brevitarsis larvae as a dietary source. In this study, we investigated the immune-enhancing activities of P. brevitarsis larvae hot-water extract (PLW) and PLW after treatment with B. velezensis TJS119 (PLWB) using the RAW 264.7 macrophage cell line. We examined the effects of PLWB on cell proliferation, cytokine production, and nitric oxide production in RAW264.7 cells. PLWB showed no cytotoxicity at concentrations ranging from 7.8 to 1,000 μg/mL in RAW264.7 cells. Treatment with PLWB increased the production of nitric oxide and pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β)] at doses of 62.5 to 1,000 μ g/mL in RAW264.7 cells. As a result, PLWB exhibited a stronger immune-enhancing effect compared to PLW. In conclusion, the results of this study offer experimental evidence to support the potential utilization of PLWB as an immunity-enhancing nutraceutical ingredient.
        14.
        2023.10 구독 인증기관·개인회원 무료
        Bacillus velezensis TJS119 was isolated from the freshwater, and antagonistic activity against of pathogenic fungi. Strain TJS119 showed a broad spectrum of antagonistic activities many fungal pathogens, including the green muscardine fungus Metarhizium anisopliae. The whole-genome sequence of B. velzensis TJS119 was analyzed using the illumina platform. The genome comprises a 3,809,913 bp chromosome with a G + C content of 46.43%, 3,834 total genes, 10 rRNA and 73 tRNA genes. The genome contained a total of 8 candidate gene clusters (difficidin, fengycin, bacillaene, macrolactin, bacillibactin, bacilysin, surfactin and butirosin) to synthesize secondary metabolite biosynthesis. Overall, our data will aid future studies of the biocontrol mechanisms of B. velezensis TJS119 and promote its application in insect disease control.
        15.
        2023.10 구독 인증기관·개인회원 무료
        Pine Wilt Disease (PWD) is a disease causing mass deaths of pine trees in South Korea, and the dead trees serve as breeding grounds for insect vectors responsible for spreading the disease to other host trees. Because the PWD requires early monitoring to minimize its damage on domestic forestry, this study aims to develop a species distribution model for predicting the potential distribution of PWD by using artificial neural network (ANN) with time-series data. Among the architectures, the Convolutional Neural Network exhibited the highest performance, achieving a validation accuracy of 0.854 and a cross-entropy loss of 0.401, and the InceptionTime model emerged as the second-best performer. This study identified the best-performing ANN architecture for a spatiotemporal evaluation of PWD occurrence, emphasizing the importance for determining hyperparameters with ecological characteristics and data types to apply deep learning into SDMs.
        16.
        2023.10 구독 인증기관·개인회원 무료
        Apolygus is one of speciose genus in subfamily Mirinae, including more than 80 species worldwide. Most of Apolygus species are phytophagous, and some species are regard as severe crop pest. For that, precise diagnosis and classification for this genus is crucial. In this work, we provide checklist of Korean Apolygus species with a new species and new distributional records. Diagnostic characters of the new species are discussed with the illustrations of adult male, female specimen and genitalic structures. A key to the Korean Apolygus is also presented.
        17.
        2023.10 구독 인증기관·개인회원 무료
        Anoplophora horsfieldii (Hope, 1843), 국명 노랑알락하늘소(가칭)는 아열대 지역에 주로 분포하는 종으로 2019 년에 제주도 용연계곡에서 처음 발견되었으며, 2023년에 국내 정착이 보고되었다. 국내에서는 팽나무에서 발생 하는 것으로 알려졌으나, 섭식방식, 산란 선호성 등 생태적 특성에 대해서는 국내외 연구가 전무하다. 따라서 본 연구에서는 노랑알락하늘소의 기초적인 생태정보를 제공하고자 실내 산란 선호성 조사 및 야외조사를 진행 했다. 산란 선호성 실험은 기주식물로 알려진 팽나무, 멀구슬나무와 제주도내 대표 수종인 동백나무, 종가시나무 을 대상으로 했다. 이 중 팽나무에서만 산란이 확인었으며, 상대적으로 굵은 팽나무에서 더 많은 산란이 확인되었 다. 야외조사에서는 최대 발생지인 용연계곡을 기준으로 반경 3 km 내에서 노랑알락하늘소의 탈출공이 확인된 32 그루의 팽나무를 대상으로 피해를 조사하였다. 나무의 굵기는 흉고직경이 20-40 cm인 팽나무에서 탈출공이 많이 확인되었고, 높이는 지면으로 부터 0-100 cm 구간에서 가장 많은 탈출공이 발견되었다.
        18.
        2023.10 구독 인증기관·개인회원 무료
        The aphid genus Tuberaphis Takahashi belongs to the tribe Cerataphdini (Hemiptera: Hormaphidinae) and comprises 17 valid species. Generally, its species are distributed in East and South East Asia, where they primarily feed on Styrax spp. (Styracaceae) and utilize species within the Loranthaceae family as their secondary hosts. They form various shapes of galls on Styrax, looking coral and broccoli etc. Currently, the only aphid species reported to exclusively produce gall forms resembling broccoli head-shaped is Tuberaphis takeouchii (Takahashi). For the first time in Korea, an aphid species forming gall structures with a broccoli-head-like appearance has been discovered. We confirmed that the species discovered in Korea is a new species through morphological and molecular comparisons with T. takenouchii (Takahashi). To comprehend the life cycle of this new species, we conducted a year-long study investigating how the gall forms change and examined aphid polymorphism across different seasons. The results of this study additionally include as followings: 1) Species identification, 2) DNA barcoding, 3) population genetic analyses, and 4) morphological comparison using SEM
        19.
        2023.10 구독 인증기관·개인회원 무료
        Miridae show remarkable diversity (>11,700 spp.), accounting for a quarter of all Heteroptera. However, their phylogeny and evolutional history is still remain unclear. In this work, we provide new suggestions for the phylogeny of Miridae using a larger dataset than previous studies. In addition, we suggest an alternative evolutionary history based on newly calibrated divergence dates for Miridae and its subordinate groups, and present probable factors of the family’s success in terms of species diversity. The entire dataset comprises 16 outgroups and 188 ingroup taxa including all seven known subfamilies and 37 out of 45 known tribes. Each species is aligned as 3,577 bp with six molecular loci (COI, 16S rRNA, 18S rRNA, 28S rRNA D3 region, H2A, and H3A).
        20.
        2023.10 구독 인증기관·개인회원 무료
        Honey bees are crucial pollinators for agricultural and natural ecosystems, but are experiencing heavy mortality in Korea due to a complex suite of factors. Extreme winter losses of honey bee colonies are a major threat to beekeeping but the combinations of factors underlying colony loss remain debatable. Finding solutions involves knowing the factors associated with high loss rates. To investigate whether loss rates are related to Varroa control and climate condition, we surveyed beekeepers in korea after wintering (2021–2022 to 2022–2023). The results show an average colony loss rate of 46%(2022) and 17%(2023), but over 40% colony loss before wintering at 2022. Beekeepers attempt to manage their honey bee colonies in ways that optimize colony health. Disentangling the impact of management from other variables affecting colony health is complicated by the diversity of practices used and difficulties handling typically complex and incomplete observational datasets. We propose a method to 1) Varroa mite population Control by several methods , and 2) Many nursing bee put in hive before wintering.
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