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  • 2025

    한국은 경제력과 군사력 측면에서 명실상부한 선진국이며, 주요 7개국 정상회의(G7) 확대 논의 당사국으로 고려된다. 그러나 한국의 합계출산율은 매년 세계에서 가장 낮은 수준이다. 이미 인구 감소가 진행 중인 한국은 미래 성장 동력을 유지하는 데에 차질을 빚을 것으로 보인다. 이에 본 논문은 먼저 한국의 인구 구조 변화에 대한 비관적 전망과 군 병력부족 실태를 다룬다. 또한 한국군의 축소가 불러올 재래식 전력의 양적, 질적 후퇴를 강조하고, 인구 절벽이 치명적 안보 문제의 도화선이 될 것이라고 본다. 이어서, 고착화된 지역 안보 갈등과 인구 절벽에 처한 한국의 국력 쇠퇴를 상쇄하기 위한 수단 중 하나로서 자체 핵무장을 안보적, 경제적 효율성 측면에서 검토한다. 종합적으로, 본 논문은 자체 핵무장이 초저출생 및 고령화 사회인 미래 한국의 안보에 유의미한 안전 장치이자 주변 적성국 대상 억제력이 될 수 있다고 결론짓는다.
    • Book : 31(1)
    • Pub. Date : 2025
    • Page : pp.123-152
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  • 2025

    While glutamate, a key neurotransmitter in the central nervous system, is fundamental to neuronal viability and normal brain function, its excessive accumulation leads to oxidative stress, contributing to neuronal damage and neurodegenerative diseases. In this study, we investigated the effect of β-lapachone (β-Lap), a naturally occurring naphthoquinone, on glutamate-induced injury in HT22 cells and explored the underlying mechanism involved. Our results show that β-Lap significantly improved cell viability in a dose-dependent manner. Additionally, β-Lap exhibited a significant antioxidant activity, reducing intracellular reactive oxygen species levels and restoring glutathione levels. The antioxidant capacity of β-Lap was further demonstrated through 2,2-Diphenyl- 1-picrylhydrazyl (DPPH) and 2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assays. Western blot analysis revealed that β-Lap upregulated brain-derived neurotrophic factor (BDNF) and promoted the phosphorylation of tropomyosin receptor kinase B (TrkB), extracellular signal-regulated kinase (ERK), and cAMP response elementbinding protein (CREB), which were downregulated by glutamate. Furthermore, β-Lap enhanced the cellular antioxidant molecules, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). In conclusion, β-Lap can protect HT22 cells against glutamate-induced injury by activating the BDNF/TrkB/ERK/CREB and ERK/Nrf2/HO-1 signaling pathways, suggesting its therapeutic potential for neurodegenerative diseases.
    • Book : 33(2)
    • Pub. Date : 2025
    • Page : pp.286-296
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  • 2025

    This paper analyzes the impact of a single soft error on the performance of a synchronous and self-timed pipeline. A nuclear particle running through the integrated circuit body is considered the most probable soft error source. The existing estimates show that self-timed circuits offer an advantage in terms of single soft error tolerance. The paper proves these estimates on the basis of a comparative probability analysis of a critical fault in two types of pipelines. The mathematical models derived in the paper describe the probability of a critical fault depending on the circuit’s characteristics, its operating discipline, and the soft error parameters. The self-timed pipeline operates in accordance with a two-phase discipline, based on the request–acknowledge interaction within the pipeline’s stages, which provides it with increased immunity to soft errors. Quantitative calculations performed on the basis of the derived mathematical models show that the self-timed pipeline has about 6.1 times better tolerance to a single soft error in comparison to its synchronous counterpart. The obtained results are in good agreement with empirical estimates of the soft error tolerance level of synchronous and self-timed circuits.
    • Book : 13(5)
    • Pub. Date : 2025
    • Page : pp.695-695
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  • 2025

    Iron smelting is one of the primary sources of carbon emissions. The development of low-carbon ironmaking technologies is essential for the iron and steel industry to realize the “dual carbon” ambition. Hydrogen-based flash ironmaking technology eliminates traditional pretreatment steps such as sintering, pelletizing, and coking while using hydrogen as a reducing agent, significantly reducing carbon emissions. In the present work, a computational fluid dynamics approach is employed to conduct an in-depth analysis of the radiative properties inside the reaction shaft of a flash smelting furnace. The results illustrate that the lowest gas absorption coefficient and volumetric absorption radiation along the radial direction appear at y = 2.84 m, with the values of 0.085 m−1 and 89,364.6 W/m3, respectively, whereas the largest values for these two variables in the axial direction can be obtained at h = 6.14 m with values of 0.128 m−1 and 132,841.11 W/m3. The reduced incident radiation intensity under case 1’s condition led to distinct differences in the radiative temperature compared to the other four cases. The spatial distributions of the particle absorption and scattering coefficients exhibit excellent consistency. The thermal conductivities of all investigated cases depict similar trends along both the axial and radial directions. Volumetric emissive radiation presents a non-linear trend of first increasing and then decreasing, followed by the rise as the height decreases. This study highlights the critical role of hydrogen-based flash ironmaking technology in reducing carbon emissions and provides valuable insights into the radiative characteristics of its reaction shaft under different operating conditions.
    • Book : 15(3)
    • Pub. Date : 2025
    • Page : pp.242-242
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  • 2025

    IntroductionThe terrestrial orchid genus Nervilia is diagnosed by its hysteranthous pattern of emergence but is nested among leafless myco-heterotrophic lineages in the lower Epidendroideae. Comprising ca. 80 species distributed across Africa, Asia and Oceania, the genus remains poorly known and plagued by vague and overlapping species circumscriptions, especially within each of a series of taxonomically intractable species complexes. Prior small-scale, exploratory molecular phylogenetic analyses have revealed the existence of cryptic species, but little is otherwise understood of origin, the scale and timing of its biogeographic spread, or the palaeoclimatic factors that have shaped its ecology and given rise to contemporary patterns of occurrence.MethodsHere, we sample widely throughout the generic range, including 45 named taxa and multiple accessions referable to several widespread ‘macrospecies’, as well as material of equivocal identity and probable undescribed status, for the first time enabling an evaluation of taxonomic boundaries at both species and sectional level. Using nuclear (ITS) and plastid (matK, trnL-F) sequence data, we conduct phylogenetic (maximum parsimony and Bayesian inference) and ancestral area analysis to infer relationships and resolve probable origin and colonisation routes.ResultsThe genus is strongly supported as monophyletic, as are each of its three sections. However, the number of flowers in the inflorescence and other floral characters are poor indicators of sectional affinity. Dated ancestral area analysis supports an origin in Africa in the Early Oligocene, with spread eastwards to Asia occurring in the Late Miocene, plausibly via the Gomphotherium land bridge at a time when it supported woodland and savanna ecosystems.DiscussionTaxonomic radiation in Asia within the last 8 million years ties in with dramatic Himalayan-Tibetan Plateau uplift and associated intensification of the Asia monsoon. Multiple long-range migrations appear to have occurred thereafter, as the genus colonised Malesia and Oceania from the Pliocene onwards. The bulk of contemporary species diversity is relatively recent, potentially explaining the ubiquity of cryptic speciation, which leaves numerous species overlooked and unnamed. Widespread disjunct species pairs hint at high mobility across continents, extinction and a history of climate-induced vicariance. Persistent taxonomic challenges are highlighted.
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  • 2025

    AbstractNon-canonical roles for growth factors in the nucleus have been previously described, but their mechanism of action and biological roles remain enigmatic. Platelet-derived growth factor B (PDGFB) can drive formation of low-grade glioma and here we show that it localizes to the nucleus of human glioma cells where it binds chromatin to preserve genome stability and cell lineage. Failure of PDGFB to localize to the nucleus leads to chromosomal abnormalities, aberrant heterochromatin architecture and accelerated tumorigenesis. Furthermore, nuclear localization of PDGFB is reliant upon the expression levels and mutation status of isocitrate dehydrogenase (IDH). Unexpectedly, we identified macrophages as the predominant source of PDGFB in human, finding that immune-derived PDGFB can localize to the nucleus of glioma cells. Collectively, these studies show that immune derived PDGFB enters the nucleus of glioma cells to maintain genomic stability, while identifying a new mechanism by which IDH mutations promote gliomagenesis.
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  • 2025


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  • 2025

    SummaryWe sought to identify new candidate drugs for repurposing to myelodysplastic syndromes (MDS). Connectivity map analysis was performed on gene expression signatures generated from bone marrow CD34+ cells of splicing factor mutant MDS patients. Celastrol and Withaferin A (WA), two top‐ranking compounds identified, markedly inhibited proliferation, arrested the cell cycle and induced apoptosis in leukaemia cells. These compounds also inhibited the viability of primary bone marrow MDS cells. We showed that Celastrol and WA inhibit interleukin‐1 receptor‐associated kinase 4‐mediated nuclear factor kappa‐light‐chain‐enhancer of activated B cells signalling activation in splicing factor mutant MDS and leukaemia cells. Celastrol and WA may represent novel candidate drugs for the treatment of MDS.
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    • Pub. Date : 2025
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  • 2025


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    • Pub. Date : 2025
    • Page : pp.101357-101357
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  • 2025


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