검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 207

        1.
        2024.04 구독 인증기관·개인회원 무료
        Haemaphysalis longicornis는 사람과 동물에게 여러 심각한 병원체를 전달하는 주요 매개체로, 한반도에 널리 분포하고 있다. H. longicornis는 Rickettsia spp., Borrelia spp., Francisella spp., Coxiella spp., 그리고 중증열성혈소판 감소증후군 바이러스 (SFTS virus) 등을 매개하는 것으로 알려져 있다. 국내에 서식하는 H. longicornis의 미생물 군집과 관련된 연구는 많이 진행되지 않은 것으로 확인되었다. 이 연구는 한반도 내 다양한 지역에서 채집된 H. longicornis의 미생물군집 다양성을 지역별, 성장 단계 및 성별에 따라 분석하였다. 2019년 6월부터 7월까지 질병관리청 권역별기후변화매개체감시거점센터 16개 지역에서 채집한 H. longicornis의 16S rRNA 유전자 V3-V4 영역을 PCR로 증폭 후 Illumina MiSeq 플랫폼으로 시퀀싱하였다. Qiime2를 활용한 미생물 다양성 분석을 통해 총 46개의 샘플에서 1,754,418개의 non-chimeric reads를 얻었으며, 평균 126개 의 operating taxonmic unit (OTU) 을 식별하여 총 1,398개의 OTU를 확인하였다. 대부분의 지역에서 Coxiella spp.가 우점종으로 나타났으며, 특히 Coxiella endosymbiont는 가장 높은 우점도를 보이며, Coxiella burnetii와 계통 발생 학적으로 유사한 것으로 확인되었다. 이 연구를 통해 분석된 결과는 각 지역의 H. longicornis 미생물군집 데이터 베이스 구축에 활용되었으며, 이를 통해 지역별 미생물군집의 특이성을 식별할 수 있게 하였다. 이는 한반도의 H. longicornis에 의한 질병 전파 연구와 이를 통한 공중보건 개선에 기여할 것으로 기대된다.
        2.
        2024.04 구독 인증기관·개인회원 무료
        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.
        6.
        2024.03 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        Glutamate-mediated oxidative stress causes neuronal cell death by increasing intracellular Ca2+ uptake, reactive oxidative species (ROS) generation, mitogen-activated protein kinase (MAPK) activation, and translocation of apoptosis-inducing factor (AIF) to the nucleus. In the current study, we demonstrated that corydaline exerts potent neuroprotective effects against glutamate-induced neurotoxicity. Treatment with 5 mmol/L glutamate increased cellular Ca2+ influx, ROS generation, MAPK activation, and AIF translocation. In contrast, corydaline treatment decreased cellular Ca2+ influx and ROS generation. Western blot analysis revealed that glutamate-mediated MAPK activation was attenuated by corydaline treatment. We further demonstrated that corydaline treatment inhibited the glutamate-mediated translocation of AIF to the nucleus. We propose that corydaline is a promising lead structure for the development of safe and effective neuroprotectants.
        4,000원
        7.
        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.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        최근 정원에 대한 관심이 증가함에 따라 자생 식물을 활용 하기 위한 연구가 진행되고 있다. 참식나무(Neolitsea sericea (Blume) Koidz).는 관상용뿐만 아니라 목재로도 이용할 수 있 다. 따라서 이 연구는 참식나무를 정원 식물 소재로 활용하기 위한 대량 증식 기술 개발을 위하여 종자의 발아 특성과 저장 특성에 대해 알아보고자 진행하였다. 2022년 11월 2일 제주 지역에서 채집한 종자를 실험에 사용하였다. 종자의 내·외부 형태 관찰을 한 결과, 종자가 탈리되는 시점에 배가 완전히 발 달한 형태를 가지고 있기 때문에 형태적휴면(morphological dormancy, MD)이 없음을 확인할 수 있었다. 수분흡수 실험 을 통하여 참식나무 종자는 72시간 이후 40% 정도의 수분흡수 율을 보여 내과피의 불투성에 의한 물리적휴면(PY, physical dormancy)이 없는 것으로 판단하였다. 채종 후 곧바로 무가 온 온실에 파종하면 이듬해 5월에 약 60%가 발아하였다. 저 온습윤처리 0, 2, 4, 8, 12주 후 25/15°C에 배양한 결과 최 종 발아율은 각각 0%, 0%, 21.1%, 32.6%, 34.7%였다. GA3 를 0, 10, 100, 1000mg·L-1 농도로 처리한 후 25/15°C에서 배양한 결과, 최종 발아율은 각각 0, 14.5, 22.7, 42.2%였다. 따라서 본 실험의 결과 8주 이상의 저온 처리 또는 GA3 처리 를 통하여 어느 정도 휴면을 타파시킬 수 있었다. 이러한 결과 를 통하여 종자는 intermediate PD를 가지는 것으로 판단 된다. 일부 발아하지 않은 종자는 deep PD를 가지고 있는 것 으로 판단하였다. 후숙 처리 실험의 결과 4주 만에 수분 함량 이 2% 이하로 감소하였고 종자는 전혀 발아하지 않았다. 따라 서 종자의 저장 특성 중 recalcittrant 특성을 지닌 난저장성 종자로 보인다.
        4,000원
        9.
        2023.11 구독 인증기관·개인회원 무료
        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.
        10.
        2023.11 구독 인증기관·개인회원 무료
        The effect of various physicochemical processes, such as seawater intrusion, on the performance of the engineered barrier should be closely analyzed to precisely assess the safety of high-level radioactive waste repository. In order to evaluate the impact of such processes on the performance of the engineered barrier, a thermal-hydrological-chemical model was developed by using COMSOL Multiphysics and PHREEQC. The coupling of two software was achieved through the application of a sequential non-iterative approach. Model verification was executed through a comparative analysis between the outcomes derived from the developed model and those obtained in prior investigations. Two data were in a good agreement, demonstrating the model is capable of simulating aqueous speciation, adsorption, precipitation, and dissolution. Using the developed model, the geochemical evolution of bentonite buffer under a general condition was simulated as a base case. The model domain consists of 0.5 m of bentonite and 49.5 m of granite. The uraninite (UO2) was assigned at the canister-bentonite interface as the potential source of uranium. Assuming the lifetime of canister as 1,000 years, the porewater mixing without uranium leakage was simulated for 1,000 years. After then, the uranium leakage through the dissolution of uraninite was initiated and simulated for additional 1,000 years. In the base case model, where the porewater mixing between the bentonite and granite was the only considered process, the gypsum tended to dissolve throughout the bentonite, while it precipitated in the vicinity of bentonite-granite boundary. However, the precipitation and dissolution of gypsum only showed a limited effect on the performance of the bentonite. Due to the low solubility of uraninite in the reduced environment, only infinitesimal amounts of uranium dissolved and transported through the bentonite. Additional cases considering various environmental processes, such as seawater or cement porewater intrusion, will be further investigated.
        11.
        2023.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 수분함량과 미생물 첨가제가 알팔파 사일리지의 발효특성과 사료가치에 미치는 영향을 알아보기 위해 수행되었다. 알팔파는 개화 10% 시기에서 수확되었으며 수분 함량(M60, M50, M40 및 M30)이 60, 50, 40 및 30%일 때 각각 이용하였다. 1500g을 샘플링한 후, 증류수 10mL을 첨가한 미첨가구(NAD)와 Lactococcus lactis 와 Pediococcus pentosaceus의 혼합물을 증류수(0.1g/10mL)에 1.5 x 1010cfu/g 농도로 희석한 후 접종한 미생물 균주 첨가구(ADD)를 3개월 및 6개월 발효하였다. 수분 및 미생물 첨가제에 따른 연평균 알팔파의 조단백, 중성세제 불용성 섬유 및 산성세제 불용성 섬유에서 차이가 없었다(p>0.05). 모든 발효기간에서 pH는 ADD의 M40에서 가장 낮았다(p<0.05). NAD 처리구에서는 젖산이 M50에서 가장 높았고(p<0.05), ADD 처리군에서는 M40 시험구에서 젖산이 가장 높았다(p<0.05). NAD와 ADD의 M60은 젖산 함량이 다른 수분 함량들에 비해 가장 낮으며(p<0.05) 낙산이 유일하게 검출되었다. 미생물군집의 상대적 풍부도는 ADD 처리구의 M40과 M50에서 Homo LAB (Enterococcus, Lactiplantibacillus, Lacticaseibacillus, Lactococcus, Pediococcus)의 비율이 가장 높았고, Clostridium은 M60에서 가장 높았다.
        4,000원
        12.
        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.
        13.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Companies are paying attention to project governance to realize their goal strategies, project success, and project value in a rapid and complex environment due to the development of information technology. This study aims to explore project governance and factors from literature review and practice guides related to project governance and empirically analyze the impact of project governance factors on IT project objective performance. The survey was conducted on project managers, project team members, and project management members with experience in carrying out business IT projects within two years at companies in various industries in Korea. The main conclusion is as follows. Among the project governance factors, disclosure and reporting that uses and reports using appropriate and reliable information about projects related to decision-making activities positively impact the achievement of IT project objectives: business success and stakeholder satisfaction. Among the project governance factors, project sponsorship, a role that effectively connects management and projects, and a project management framework that provides tools, procedures, resources, and techniques for projects positively impact IT project objective performance. This study is of academic and practical significance in that it identifies the definition and factors of project governance through companies in various industries in Korea and the positive impact of project governance factors on IT project objective performance.
        4,000원
        14.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to determine the appropriate seeding dates by verifying the difference in winter survival and productivity of alfalfa according to fall sowing dates in the central area of South Korea. The experiment was conducted for 2 years (2020 and 2021) at the field in the Department of Animal Resources Development, NIAS located in Cheonan. Sowing dates started from September 18 to November 8 with 10 days of intervals during 2020 and 2021; SO1 (September 18), SO2 (September 28), SO3 (October 8), SO4 (October 18), SO5 (October 28), and SO6 (November 8). After sowing, the winter survival rate was measured in the spring of the following year, and the dry matter yield was measured by harvesting at 10% flowering and harvesting five times a year. SO6 failed to winter survival, and SO5 also had a lower winter survival rate than SO1~4 (p<0.05). The average annual dry matter yield of alfalfa linearly decreased with delaying sowing dates (p<0.05). The feed value did not differ in the same year by delaying the sowing date in the same year. These results suggest that sowing date should be started before October 18 to increase winter survival and productivity of alfalfa in the central area of South Korea.
        4,000원
        1 2 3 4 5