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        검색결과 440

        1.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        최근 딥러닝은 자기공명영상 검사에서의 화질 개선을 위해 다양하게 활용되고 있다. 하지만 다양한 자기공명영상 검사에서 딥러닝이 적용된 기법과 상황에 대한 평가는 부족한 편이다. 이에 본 연구에서는 모션 ACR(American College of Radiology) 팬텀을 활용하여 일반적인 상황과 움직이는 상황에서 T2-PROPELLER(periodically, rotated overlapping parallel lines with enhanced reconstruction, PROPELLER)와 T2-FSE(fast spin echo, FSE) 기법의 화질을 비교 평가해 보고자 하였다. 연구 결과 움직이지 않는 상황에서의 딥러닝 프로세스를 적용하였을 때 유의미한 신호대잡음비와 대조대잡음비의 상승을 보였다. 하지만 팬텀에 움직임을 주는 동적인 상황 에서 딥러닝 프로세스를 적용하였을 때 유의미한 화질 개선을 보이지 않았다. 이러한 결과는 딥러닝 프로세스를 절대 적으로 사용하기보다 다양한 상황에 맞게 선택적으로 적용하는 것이 필요할 것으로 사료된다.
        4,000원
        2.
        2024.06 KCI 등재 구독 인증기관·개인회원 무료
        Inflammatory bowel disease (IBD) is a chronic condition characterized by continuous inflammation of the gastrointestinal tract that varies in intensity over time. IBD is caused by several factors including aberrant gut flora, immunological dysregulation, altered environmental conditions, and genetic variations. However, the pathogenesis of IBD remains unclear. Studies have indicated that an imbalance between T helper 17 (Th17) and regulatory T (Treg) cells contributes significantly to the development of IBD. Intestinal Tregs suppress inflammation and are critical for maintaining tissue homeostasis. Th17 cells are known to play an important role in the development and pathogenesis of IBD and provide non-inflammatory support for the integrity of the intestinal barrier against bacterial and fungal infections. Therefore, the Th17/Treg cell balance is crucial in the pathogenesis of IBD and gut integrity. The microenvironment of the intestinal mucosal immunity is regulated by the secretion of cytokines associated with Th17 cells and Tregs. Several studies have indicated that the gut bacteria contribute to the control of the immune milieu and play a key role in the regulation of Th17 cell development. Intestinal bacteria and cytokines control Th17 cell development. Th17 cells secrete cytokines that regulate the immune microenvironment in the gut mucosa. This review provides an overview of Th17 cells and examines the strategies for treating patients with IBD using Th17 cell-targeted drugs.
        8.
        2024.04 구독 인증기관·개인회원 무료
        The Korea Forest Service has designated seven alpine tree species—Abies koreana, A. nephrolepis, Juniperus chinensis, Picea jezoensis, Pinus pumila, Taxus cuspidata, and Thuja koraiensis—as threatened with extinction in Korea. In 2023, we conducted a study on the seasonal occurrence of insect pests, focusing mainly on two coleopteran taxa (Cerambycidae and Scolytinae) and two hemipteran taxa (Aphrophoridae and Cicadellidae) in subalpine forests dominated by A. koreana, A. nephrolepis, Picea jezoensis, Thuja koraiensis, and Taxus cuspidata. We utilized three types of traps—Malaise trap, Lindgren funnel trap, and window trap—in eight investigation locations in Korea. In this presentation, we present the study results and discuss the effects of insect pests on alpine coniferous trees in Korea.
        9.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Animal experiments have demonstrated the effectiveness of fermented rice germ and soybean extracts in lowering blood alcohol concentration. A compound primarily derived from fermented soybean extract constitutes the principal component of DA-5521, an experimental dietary substance examined in this study. We investigated the possible hangover-alleviating effects of DA-5521 in individuals aged 19 to 50 who had previously experienced hangovers. Moreover, we enrolled 22 participants who met the eligibility criteria and conducted a double-blind, randomized, placebo-controlled crossover trial. Six hours after alcohol consumption, the test group exhibited a statistically significant reduction in blood acetaldehyde concentration compared with the placebo group. Further, our results displayed significantly lower levels in the DA- 5521 group at 0.50 and 0.75 h post-ingestion and substantially lower peak breath alcohol concentration compared to the placebo group. These findings confirm that consumption of DA-5521 can significantly ameliorate hangover symptoms by diminishing blood acetaldehyde concentration and reduce breath alcohol concentration.
        4,200원
        10.
        2024.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Korean historical literatures offer numerous records on astronomical phenomena such as eclipses, comets, and close approaches, etc. Records of close approaches often use specific terms to describe the angular distance, which lack translation into modern numerical values. We study the usage of the five commonly used terms, namely, Entry (入, En), Invasion (犯, In), Occultation (掩, Oc), Eclipse (食, Ec), as well as the unit Chi (尺). Our analysis is based on more than 2,300 records from Goryeo (918–1392 CE) and Joseon (1392–1910 CE) Dynasties. Through statistical analysis, we determine their quantitative definitions. We convert the lunisolar calendar to the Julian and Gregorian date and utilize the modern ephemeris DE431 to calculate the angular distance between celestial bodies. We find that the angular distances of the terms En, In, Oc, and Ec correspond to respectively 1.78◦+2.36 −1.11, 0.89◦+3.54 −0.51, 0.44◦+1.15 −0.31, and 0.29◦+2.61 −0.16 for the Goryeo Dynasty and 1.36◦+1.15 −0.64, 0.51◦+1.11 −0.32, 0.25◦+0.27 −0.17, and 0.21◦+0.25 −0.11 for the Joseon Dynasty. Additionally, we determine the angular size of the unit Chi by using the records from Korean chronicles along with the drawings of comets’ tails in the Daily Log (天變謄錄). We estimate the unit Chi to be 1.11◦+0.46 −0.40 and find that the numerical definition was consistent throughout the two dynasties in Korea. Furthermore, we find that the terms were used to describe the closest approach and that there is no observational bias in the angular distances against the apparent magnitudes of the objects. We show that the terms En, In, Oc, and Ec represent decreasing angular distance in that order and this ordering was consistent in both dynasties.
        4,000원
        11.
        2024.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In recent times, there has been a significant demand for supercapacitors in energy storage applications due to their rapid charging– discharging capabilities, high power density, and excellent stability. Nevertheless, the synthesis of electrode materials with a substantial surface area, exceptionally high porosity, and superior electrochemical performance is still challenging. Activated carbons with a distinctive porous structure and exceptional electrochemical properties emerged as promising electrode materials for supercapacitors. In this study, we used a porous activated carbon (PAC) derived from petroleum coke followed by KOH activation as an efficient anodic electrode material. The ultra-high Brunauer–Emmett–Teller surface area of 2105.6 m2 g− 1 with stacked layers of carbon atoms arranged in a two-dimensional hexagonal structure makes the PAC an efficient candidate for a supercapacitor electrode. The PAC delivers a specific capacitance of 470 F g− 1 at a current density of 0.5 A g− 1 over a potential window of 0 to −1 V. The excellent cycling stability in a three-electrode setup with a capacitance retention of ⁓98% even at a high current density of 10 A g− 1 makes the PAC a potential anodic electrode material for high-performance supercapacitor applications.
        4,000원
        12.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Pitfall traps that use ethylene glycol as a preservative solution are commonly used in arthropod research. However, a recent surge in cases involving damage to these traps by roe deer or wild boars owing to the sweet taste of ethylene glycol has prompted the addition of quinone sulfate, a substance with a pungent taste, to deter such wildlife interference. This study aimed to assess the effects of quinone sulfate on arthropods collected from pitfall traps containing ethylene glycol. We strategically positioned 50 traps using ethylene glycol alone and 50 traps containing a small amount of quinone sulfate mixed with ethylene glycol in a grid pattern for systematic sampling at the Gwangneung Forest long-term ecological research (LTER) site. Traps were collected 10 days later. The results revealed a notable effect on ants when quinone sulfate was introduced. Specifically, it decreased the number of ants. In a species-specific analysis of ants, only Nylanderia flavipes showed a significant decline in response to quinone sulfate, whereas other ant species remained unaffected. Additionally, among the arthropod samples obtained in this survey, we identified species or morpho-species of spiders, beetles, and ants and assessed species diversity. Consequently, the utilization of quinone sulfate should be undertaken judiciously, taking into account the specific species composition and environmental characteristics of the monitoring site. Our study also highlighted the significant response of various arthropod groups to variations in leaf litter depth, underscoring the crucial role of the leaf litter layer in providing sustenance and shelter for ground-foraging arthropods. Furthermore, we have compiled comprehensive species lists of both spiders and ants in Gwangneung forest by amalgamating data from this investigation with findings from previous studies.
        5,100원
        13.
        2023.12 KCI 등재 구독 인증기관·개인회원 무료
        현대 사회에서 첨단 기술의 발전은 예술의 양상을 빠르게 변화시키고 있다. 생성형 인공지능 기술의 발전은 인류의 전유물이라 여겨왔던 창작 행위에 기존에는 보지 못했던 색다른 표현을 제공했다. 또한, 전통적 기법 을 고수하던 예술인들에게 새로운 예술 창작의 발현 방식을 제시하였다. 하지만 나날이 발전하는 인공지능 기술에 비해, 이를 활용한 구체적인 미디어아트 제작 과정 연구는 아직 국내에서는 미비하다. 본 논문은 인 공지능 기술을 활용한 미디어아트 해외 사례를 탐구한다. 그리고 Text-to-Image 인공지능 생성 모델과 게임 엔진 Unreal Engine 5를 이용하여, 국내에 자리 잡지 않은 생성형 인공지능을 활용한 작품 제작 방법론과 창 작자들에게 인공지능 이미지 생성 모델의 확장성을 제시한다.
        14.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to prepare kombucha, a fermented tea beverage, containing Dendropanax morbiferus (DM) leaves and roots, and analyze its antioxidant and intracellular activities. We compared the pH change, total acidity, radical scavenging activity, and oxygen radical absorbance capacity (ORAC) of kombucha fermented with black tea alone and that with added DM leaves or roots during fermentation. Using RAW 264.7, we evaluated the effects of kombucha containing different DM parts on nitric oxide (NO) production and inflammation-related cytokine content in cells. Kombucha containing ethanol extracts of DM leaves (BTK-E-DML) and roots (BTK-E-DMR) showed higher radical scavenging activity and ORAC 3 d after fermentation than that prepared from black tea alone (BTK-Ori). In an in vitro experiment using RAW 264.7, samples were treated with 8 mg/mL kombucha considering cytotoxicity; the lipopolysaccharide (LPS)-induced NO content significantly reduced after BTK-E-DML and BTK-EDMR treatments compared with that after BTK-Ori treatment. Additionally, the levels of interleukin-6 and tumor necrosis factor-alpha, which were LPS-stimulated inflammatory cytokines, significantly decreased in cells treated with BTK-E-DML and BTK-E-DMR 15 d after fermentation compared with those treated with BTK-Ori. In conclusion, these results demonstrate that kombucha fermented with the leaves and roots of DM increases antioxidant activity and can significantly regulate inflammatory responses at the cellular level.
        4,000원
        20.
        2023.11 구독 인증기관·개인회원 무료
        Spent ion exchange resins have been generated during the operation of nuclear facilities. These resins include radioactive nuclides. It is needed to fabricate them into a stable form for final disposal. Cement solidification process is a useful method for the fabrication of them into a waste form for final disposal. In this study, proper conditions for the fabrication of them into a stable waste form were determined using the cement solidification process. In-drum waste forms were then produced at the conditions, where the stability of representative samples was evaluated for final disposal. The samples were satisfied to the Waste Acceptance Criteria for low and intermediate level radioactive waste disposal sites. This result can be utilized to derive optimal conditions for the fabrication of spent ion exchange resins into a final disposal form.
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