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Hypersonic Weapons and National Security (극초음속 무기체계의 개발 경쟁과 국가 안보의 함의)

  • Son, Hyun-Seung;Lee, Ho-il;Ko, Duk-Gon
    • Journal of Aerospace System Engineering
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    • v.16 no.1
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    • pp.56-69
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    • 2022
  • Various advanced countries are accelerating the competition in the development of hypersonic weapons. North Korea is on the verge of building a new submarine equipped with a submarine-launched ballistic missile (SLBM). A series of new guided missiles tests have continued due to political competition between the U.S. and China. The Republic of Korea is planning to boost its military capabilities, which involves the development of nuclear-powered submarines, light aircraft carriers, and new guided missiles. The northeast Asian region continues to be tense amid military rivalry between the Republic of Korea, North Korea, the United States, China, Russia, and Japan. Accordingly, these countries' competition to develop weapons is also at the world's highest level. In this paper, we examine the functioning of a hypersonic weapons system conduct a technical analysis of its components. In addition, we analyze the direction of military development that the Korean military wants to pursue through the recently announced mid-term defense plan. We conclude by highlighting the technical limitations and implementation strategies to overcome the development of hypersonic weapons.

A Study for the Efficient Improvement Measures of Military EMP Protection Ability (국방 EMP 방호능력의 효율적 개선을 위한 방안 연구)

  • Jung, Seunghoon;An, Jae-Choon;Hwang, Yeung-Kyu;Jung, Hyun-Ju;Shin, Yongtae
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.1
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    • pp.219-227
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    • 2017
  • Current military command information system uses electronic equipment a lot on which semiconductor chip is attached. It seems its' importance will increase more with latest information communication technology developing. Electronic equipment which uses electricity contains regular tolerance to high output electric signal. And EMC specification is the standardized of this electronic equipment's tolerance. On the other hand, the Institute of Atomic Energy Research has ever declared that high output electromagnetic pulse(EMP) will be broken out within the radius of 170Km when 10kt nuclear explosion occurs at an altitude of 40Km above Seoul. Then, the region suffer from the damage of most electronic equipments. Therefore, the norm to protect the influences in that case is defined by EMP protection specification. Most common electronic equipments meet the EMC norm, but there is no way to check whether they meet the EMP norm or not. That is because it is difficult to check whether they meet EMP protection norm and is on the matter of cost. Except inevitable cases, there is no review of checking whether they meet the norm or not. Considering the above, in this research, we speculate about the measures to improve military EMP protection ability by analyzing the EMC-EMP correlation and checking the EMP protection ability of general electronic equipment through the analysis.

Change of Peroxiredoxin-5 Expression by Curcumin Treatment in Cerebral Ischemia (허혈성 대뇌손상시 curcumin 투여에 의한 peroxiredoxin-5 발현의 변화)

  • Gim, Sang-Ah;Koh, Phil-Ok
    • Journal of agriculture & life science
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    • v.50 no.3
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    • pp.129-139
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    • 2016
  • Curcumin plays a protective role in brain injury through its anti-oxidant and anti-inflammatory activities. Moreover, peroxiredoxin-5 exerts a protective effect against oxidative stress. The aim of this study was to investigate whether curcumin modulated the peroxiredoxin-5 expression in focal cerebral ischemic animal model. Middle cerebral artery occlusion(MCAO) was performed to induce cerebral ischemic injury in rats. Adult male rats were injected intraperitoneally with vehicle or curcumin(50mg/kg B.W.) 1 h after MCAO and cerebral cortex tissues were collected 24 h after MCAO. Photographs of hematoxylin and eosin staining showed that MCAO induced necrotic changes with scalloped shrunken form and apoptotic changes with nuclear chromatin condensations. However, curcumin treatment attenuated MCAO-induced histopathological changes. Moreover, this study clearly showed that peroxiredoxin-5 expression was decreased in MCAO operated animal with vehicle using a proteomics approach. However, this decrease in peroxiredoxin-5 expression was attenuated by curcumin treatment. Reverse-transcription PCR and Western blot analyses confirmed that curcumin treatment alleviated the MCAO injury-induced decrease in peroxiredoxin-5 expression(p<0.05). These results demonstrated that curcumin regulates peroxiredoxin-5 expression in MCAO animal model. In conclusion, our findings suggest that curcumin exerts a neuroprotective effect in cerebral ischemia by attenuating the MCAO-induced decrease in peroxiredoxin-5 expression.

Anti-cancer activity of the ethylacetate fraction from Orostachys japonicus in A549 human lung cancer cells by induction of apoptosis and cell cycle arrest (인체 폐암 세포에 대한 와송 유래 에틸아세테이트 분획 생리 활성 물질의 세포사멸 유도 및 세포주기 억제 항암활성)

  • Kwon, Ji-Hye;Lee, Dong-Seok;Jung, Eun-Cheol;Kim, Hyeon-Mi;Kim, Su-Bin;Ryu, Deok-Seon
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.1
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    • pp.395-405
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    • 2017
  • To confirm potential anti-cancer activities of ethylacetate (EtOAc) fraction from Orostachys japonicus on the A549 human lung cancer cells, this study examined. As a result of conducting MTS assay for measuring cell viability, the EtOAc fraction inhibited the proliferation of A549 cells in a dose-dependent manner. To investigate whether the inhibiting A549 cell viability was caused by apoptosis, this study analyzed chromatin condensation in A549 cells using DAPI staining. The morphological changes such as the formation of nuclear condensation were formed in a dose-dependent manner. Also, this study performed Annexin V-FITC staining for detecting phosphatidylinositol (PS). As a result of Annexin V-FITC staining to investigate level of early and late apoptosis, the apoptosis level treated with EtOAc fraction was higher than that of control. RT-PCR was performed to study the correlation between G2/M cell cycle arrest and cell cycle control genes. The anti-cancer activity of EtOAc fraction was accompanied by inhibition of CDK1, 4, cyclin B1 and D1 mRNA. This study also examined the expression of various marker proteins: p53, Bax, Bcl-2 and pro-caspase 3. Western blotting revealed that p53 and Bax proteins were up-regulated, and Bcl-2 and pro-caspase 3 proteins down-regulated in a time and dose-dependent manner.

The Utility of Chatbot for Learning in the Field of Radiology (방사선(학)과 분야에서 챗봇을 이용한 학습방법의 유용성)

  • Yoon-Seo Park;Yong-Ki Lee;Sung-Min Ahn
    • Journal of the Korean Society of Radiology
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    • v.17 no.3
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    • pp.411-416
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    • 2023
  • The purpose of this study is to investigate the utilization of major learning tools among radiology science students and assess the accuracy of a conversational artificial intelligence service program, specifically a chatbot, in the context of the national radiologic technologist licensing exam. The survey revealed that 84.3% of radiology science students actively utilize electronic devices during their learning process. In addition, 104 out of 140 respondents said they use search engines as a top priority for efficient data collection while studying. When asked about their awareness of chatbots, 80% of participants responded affirmatively, and 22.9% reported having used chatbots for academic purposes at least once. From 2018 to 2022, exam questions from the first and second periods were presented to the chatbot for answers. The results showed that ChatGPT's accuracy in answering first period questions increased from 48.28% to 60%, while for second period questions, it increased from 50% to 62.22%. Bing's accuracy in answering first period questions improved from 55% to 64.55%, and for second period questions, it increased from 48% to 52.22%. The study confirmed the general trend of radiology science students utilizing electronic devices for learning and obtaining information through the internet. However, conversational artificial intelligence service programs in the field of radiation science face challenges related to accuracy and reliability, and providing perfect solutions remains difficult, highlighting the need for continuous development and improvement.

Recombinant human KAI1/CD82 attenuates M1 macrophage polarization on LPS-stimulated RAW264.7 cells via blocking TLR4/JNK/NF-κB signal pathway

  • Hyesook Lee;Jung-Hwa Han;Kangbin An;Yun Jeong Kang;Hyun Hwangbo;Ji Hye Heo;Byung Hyun Choi;Jae-Joon Kim;Seo Rin Kim;Soo Yong Lee;Jin Hur
    • BMB Reports
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    • v.56 no.6
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    • pp.359-364
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    • 2023
  • KAI1/CD82, a membrane tetraspanin protein, can prevent various cancers and retinal disorders through its anti-angiogenic and anti-metastatic capacity. However, little is known about its anti-inflammatory effect and molecular mechanism. Therefore, the present study aimed to inLPSvestigate effect of a recombinant protein of the large extracellular domain of human KAI1 (Gly 111-Leu 228, rhKAI1) on lipopolysaccharides (LPS)-stimulated RAW264.7 macrophage-like cells and mouse bone marrow-derived macrophages (BMDM) and to identify its underlying mechanism. Our data showed that rhKAI1 suppressed expression levels of classically macrophages (M1) phenotype-related surface markers F4/80+CD86+ in LPS-stimulated BMDM and RAW264.7 cells. In addition, LPS markedly increased mRNA expression and release levels of pro-inflammatory cytokines and mediators such as interleukin (IL)-1β, IL-6, tumor necrosis factor-α, cyclooxygenase-2, nitric oxide and prostaglandin E2, whereas these increases were substantially down-regulated by rhKAI1. Furthermore, LPS strongly increased expression of NF-κB p65 in the nuclei and phosphorylation of ERK, JNK, and p38 MAPK. However, nuclear translocation of NF-κB p65 and phosphorylation of JNK were greatly reversed in the presence of rhKAI1. Especially, rhKAI1 markedly suppressed expression of toll-like receptor (TLR4) and prevented binding of LPS with TLR4 through molecular docking predict analysis. Importantly, Glu 214 of rhKAI1 residue strongly interacted with Lys 360 of TLR4 residue, with a binding distance of 2.9 Å. Taken together, these findings suggest that rhKAI1 has an anti-inflammatory effect on LPS-polarized macrophages by interacting with TLR4 and down-regulating the JNK/NF-κB signaling pathway.

Fisetin Protects C2C12 Mouse Myoblasts from Oxidative Stress-Induced Cytotoxicity through Regulation of the Nrf2/HO-1 Signaling

  • Cheol Park;Hee-Jae Cha;Da Hye Kim;Chan-Young Kwon;Shin-Hyung Park;Su Hyun Hong;EunJin Bang;Jaehun Cheong;Gi-Young Kim;Yung Hyun Choi
    • Journal of Microbiology and Biotechnology
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    • v.33 no.5
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    • pp.591-599
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    • 2023
  • Fisetin is a bioactive flavonol molecule and has been shown to have antioxidant potential, but its efficacy has not been fully validated. The aim of the present study was to investigate the protective efficacy of fisetin on C2C12 murine myoblastjdusts under hydrogen peroxide (H2O2)-induced oxidative damage. The results revealed that fisetin significantly weakened H2O2-induced cell viability inhibition and DNA damage while blocking reactive oxygen species (ROS) generation. Fisetin also significantly alleviated cell cycle arrest by H2O2 treatment through by reversing the upregulation of p21WAF1/CIP1 expression and the downregulation of cyclin A and B levels. In addition, fisetin significantly blocked apoptosis induced by H2O2 through increasing the Bcl-2/Bax ratio and attenuating mitochondrial damage, which was accompanied by inactivation of caspase-3 and suppression of poly(ADP-ribose) polymerase cleavage. Furthermore, fisetin-induced nuclear translocation and phosphorylation of Nrf2 were related to the increased expression and activation of heme oxygenase-1 (HO-1) in H2O2-stimulated C2C12 myoblasts. However, the protective efficacy of fisetin on H2O2-mediated cytotoxicity, including cell cycle arrest, apoptosis and mitochondrial dysfunction, were greatly offset when HO-1 activity was artificially inhibited. Therefore, our results indicate that fisetin as an Nrf2 activator effectively abrogated oxidative stress-mediated damage in C2C12 myoblasts.

The Meaning of Parenthood and Christian Educational Care (부모 됨의 의미와 기독교 교육적 돌봄)

  • Jeung-Gwan Lee
    • Journal of Christian Education in Korea
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    • v.72
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    • pp.49-70
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    • 2022
  • The purpose of this study is to suggest a response and solution through Christian educational care to the crisis and change of the era of low birth rate faced by Korean society and the Korean church. This study proposes to find an alternative to the biblical aspect of pregnancy, childbirth, and parenthood as God's blessing for the demographic cliff and low birth rate problem that have become a reality in Korean society and churches. Being a parent in an age of low birth rate is very difficult, but on the other hand, it gives happiness and joy. Being a parent is a blessing from God, and is the most important and valuable thing in life. However, modern society emphasizes the right and necessity to choose one's own parenthood status. In the nuclear family, the decrease in the number of children, and the development of child research, parents feel more responsibility and economic burden for raising children than ever before. Therefore, it is a reality that the number of people who delay becoming parents or voluntarily do not have children is gradually increasing. To improve the perception of becoming a parent due to a decrease in responsibility for raising children, it is necessary to shed light on marriage, pregnancy, childbirth, and childrearing from a Christian educational point of view. In addition, it is necessary to understand the recognition of being a parent and the characteristics of childbirth and rearing, and to analyze past and present value changes. This study will also discuss the causes of low birthrate and try to provide Christian educational care for childcare including solving the low birthrate problem.

A Comparison Study on Interest of Dietary Life Behavior, Nutrient Intake and Health between Full-Time and Working Housewives (전업 주부와 직업주부의 식생활, 영양소 섭취상태 및 건강에 대한 관심도 비교 연구)

  • Shin, Kyung-Ok;Yoon, Jin-A;Lee, Jun-Sik;Chung, Keun-Hee;Choi, Soon-Nam
    • Journal of the Korean Society of Food Culture
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    • v.25 no.3
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    • pp.285-295
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    • 2010
  • The purpose of this study was to compare the awareness of dietary patterns and health of full-time and employed housewives. The investigation gathered information on general characteristics, dietary lifestyle, nutritional status, and health by questionnaire as well as anthropometric measurements. The subjects included housewives living in Seoul and Gyeonggi Province (86 full-time and 127 working housewives) during November 2009 to January 2010. The average age, height, and weight of the housewives were $45.8{\pm}7.6\;yr$, $161.0{\pm}8.4\;cm$, and $55.7{\pm}6.3\;kg$, respectively. The average monthly income of the households was 3 million to 5 million won (31.4% full-time and 37.0% working housewives), and their average food expense was 200,000 to 500,000 won (46.5% full-time and 48.1% working housewives). More than 90% of the studied homes were nuclear families and the most common number of children was 2 to 3 (79.1% full-time and 76.4% working housewives). The ratio of employed housewives who ate regular meals was 35.4%, but that of the full-time housewives was 48.2% (p<0.05). Of the working housewives, 7.1% never ate breakfast and the primary reason for skipping breakfast was 'busy in the morning' (61.1%). The type of food that the housewives preferred when eating out was Korean food, both for the full-time and employed housewives (76.0%). All the housewives overate calories and the full-time housewives ate more protein, fat, vitamin A, vitamin B1, vitamin B6, niacin, vitamin C, vitamin E, folic acid, and cholesterol than the employed housewives (p<0.05). Both the full-time and employed housewives were more satisfied with supper than with other meals. About 30.6% of the full-time and 33.9% of the working housewives had no interest in health, but answered that regular exercise was very important for health (33.3% full-time and 39.7% working housewives). In conclusion, working housewives have poor dietary habits and nutrient intakes, thus substantial measures to improve these problems are urgently needed.

Liver Protective Effect of the Co-treatment of Rhei Radix et Rhizoma and Silymarin on TAA-induced Liver Injury (대황과 실리마린의 병용투여의 간섬유화 보호 효과)

  • Il-ha Jeong;Sang-woo Ji;Seong-soo Roh
    • The Journal of Internal Korean Medicine
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    • v.44 no.3
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    • pp.402-417
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    • 2023
  • Objective: Liver fibrosis is a highly conserved wound-healing response and the final common pathway of chronic inflammatory injury. This study aimed to evaluate the potential anti-fibrotic effect of the combination of Rhei Radix et Rhizoma water extract (RW) and silymarin in a thioacetamide (TAA)-induced liver fibrosis model. Methods: The liver fibrosis mouse model was established through the intraperitoneal injection of TAA (1 week 100 mg/kg, 2-3 weeks 200 mg/kg, 4-8 weeks 400 mg/kg) three times per week for eight weeks. Animal experiments were conducted in five groups; Normal, Control (TAA-induced liver fibrosis mice), Sily (silymarin 50 mg/kg), RSL (RW 50 mg/kg+silymarin 50 mg/kg), and RSH (RW 100 mg/kg+silymarin 50 mg/kg). Biochemical analyses were measured in serum, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), malondialdehyde (MDA), and ammonia levels. Liver inflammatory cytokines and fibrous biomarkers were measured by Western blot analysis, and liver histopathology was evaluated through tissue staining. Results: A significant decrease in the liver function markers AST and ALT and a reduction in ammonia and total bilirubin were observed in the group treated with RSL and RSH. Measurement of reactive oxygen species and MDA revealed a significant decrease in the RSL and RSH administration group compared to the TAA induction group. The expression of extracellular matrix-related proteins, such as transforming growth factor β1, α-smooth muscle actin, and collagen type I alpha 1, was likewise significantly decreased. All drug-administered groups had increased matrix metalloproteinase-9 but a decreasing tissue inhibitor of matrix metalloproteinase-1. RSL and RSH exerted a significant upregulation of NADPH oxidase 2, p22phox, and p47phox, which are oxidative stress-related factors. Furthermore, pro-inflammatory proteins such as cyclooxygenase 2 and interleukin-1β were markedly suppressed through the inhibition of nuclear factor kappa B activation. Conclusions: The administration of RW and silymarin suppressed the NADPH oxidase factor protein level and showed a tendency to reduce inflammation-related enzymes. These results suggest that the combined administration of RW and silymarin improves acute liver injury induced by TAA.