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  • 2025

    Abstract Space infrared cameras perform non-uniformity correction of detectors through on-board calibration in orbit. Using the blackbody component inside the camera as a standard radiation source is a commonly used method. As the accuracy of calibration increases, there are also high requirements for the temperature stability and uniformity of the blackbody inside the camera. This article addresses the problem of thermal control of large-scale internal black bodies and proposes a hybrid temperature control method that relies primarily on radiation and is supplemented by thermal conduction. By modulating the thermal resistance of thermal conduction, the influence ratio of radiation and thermal conduction can be adjusted to ensure control capability while maximizing the temperature uniformity of the controlled black body. After flight verification, the blackbody temperature stability can reach ±0.1K, and the temperature uniformity can reach 0.2K, meeting the calibration accuracy requirements of remote sensing imaging. This article improves the traditional blackbody control scheme that relies solely on temperature control algorithms, introducing active and passive thermal control measures to meet the new requirements of large-scale blackbodies. The scheme adopted can provide a reference for temperature control of large-scale surface source blackbody.
    • Book : 2977(1)
    • Pub. Date : 2025
    • Page : pp.012067-012067
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  • 2025

    ABSTRACTBackground and AimsTropical plants are assumed to be especially vulnerable to global warming because their physiologies are adapted to relatively constant temperatures throughout the year. Furthermore, it has been found that woody plants in colder high elevation environments are less tolerant to high temperatures than plants in the warmer lowlands. Here, we examined heat tolerance in a group of herbaceous plants with a wide elevational distribution in the tropics.MethodsThis study focused on 61 species from the order Zingiberales (ginger and banana-like plants) distributed from the lowlands (50 m asl) to lower montane forests (2000 m asl) along the Barva elevational gradient in Costa Rica.This study addressed the following questions:a)Does heat tolerance of Zingiberales species differ along the elevational gradient?b)Does heat tolerance vary along the elevational gradient within families of Zingiberales?c)Does heat tolerance vary along the elevational gradient within species for those with broad elevational distributions? To test if the temperature that causes damage to the function of photosystem II (PSII) in Zingiberales is associated with the temperatures prevalent at their elevation, we estimated heat tolerance (T50) of PSII using chlorophyll fluorescence techniques.Key ResultsIn contrast to the results found in tropical trees, our results showed that T50is higher at higher elevations than in the lowlands for herbaceous plants species. This trend was observed across plant communities and families, and within most species with wide distributions along the elevational gradient.ConclusionsOur study suggests that herbs differ from trees in their elevational patterns in heat tolerance. We hypothesize that maximum and minimum leaf temperatures, and UV radiation may play a role in the observed pattern.
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    • Pub. Date : 2025
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  • 2025

    Over 64 million people worldwide are affected by heart failure (HF), a condition that significantly raises mortality and medical expenses. In this study, we explore the potential of retinal optical coherence tomography (OCT) features as non-invasive biomarkers for the classification of heart failure subtypes: left ventricular heart failure (LVHF), congestive heart failure (CHF), and unspecified heart failure (UHF). By analyzing retinal measurements from the left eye, right eye, and both eyes, we aim to investigate the relationship between ocular indicators and heart failure using machine learning (ML) techniques. We conducted nine classification experiments to compare normal individuals against LVHF, CHF, and UHF patients, using retinal OCT features from each eye separately and in combination. Our analysis revealed that retinal thickness metrics, particularly ISOS-RPE and macular thickness in various regions, were significantly reduced in heart failure patients. Logistic regression, CatBoost, and XGBoost models demonstrated robust performance, with notable accuracy and area under the curve (AUC) scores, especially in classifying CHF and UHF. Feature importance analysis highlighted key retinal parameters, such as inner segment-outer segment to retinal pigment epithelium (ISOS-RPE) and inner nuclear layer to the external limiting membrane (INL-ELM) thickness, as crucial indicators for heart failure detection. The integration of explainable artificial intelligence further enhanced model interpretability, shedding light on the biological mechanisms linking retinal changes to heart failure pathology. Our findings suggest that retinal OCT features, particularly when derived from both eyes, have significant potential as non-invasive tools for early detection and classification of heart failure. These insights may aid in developing wearable, portable diagnostic systems, providing scalable solutions for personalized healthcare, and improving clinical outcomes for heart failure patients.
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    • Pub. Date : 2025
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  • 2025

    Abstract Transient heat flux up to thousands of MW/m2 in a short pulse (~ms) in tokamak poses great challenge on plasma facing components (PFCs), a major concern for ITER. Despite numerous high heat flux tests, the analysis of in situ transient heat flux-induced damage on PFCs remains necessary. Such damages, including the melting and cracking of tungsten (W) PFCs, are notably observed on the divertor (dome and baffle plates) and limiter in EAST. These damages are identified as being induced by runaway electron loss during plasma disruption in the early startup phase of each plasma campaign. They typically occur at the leading edges or protruding parts of PFCs, sometimes accompanied by visible macrocracks. Regarding melting phenomena, three distinct grain layers are observed from the molten surface to the deeper regions: columnar grain, equiaxed grain (recrystallization region) and original grain. This grain distribution indicates a steep temperature gradient from the surface to the deeper regions during melting events, a characteristic feature for W under fusion-relevant transient heat flux loading from electron/ion beam tests. The surface morphologies of all melted PFCs are generally similar, characterized by undulated melting waves. The movement of the melting layer is primarily along the toroidal direction, as shown in the in-situ melting PFCs. The influence of the J×B force might not be significant due to the limited life of the melting pool, which results in limited acceleration time and expected bulk melt displacements, even if the J×B force is the dominant force. The directions of plasma pressure and Marangoni flow, both along the toroidal direction, might be the dominant forces here. Additionally, cracks at leading edges were observed on the divertor dome and baffle plates during post-mortem inspection. In some cases, dense cracks were visible in the melting region and even in areas far from the melting zone. It should be noted that cracks were only found on partially melted PFCs, which could be related to the base temperature when PFCs were hit by the runaway electron-induced transient heat flux. Furthermore, some columnar grains were observed to exfoliate from the material, indicating severe cracking. Since EAST has similar W PFCs to ITER, the transient heat flux-induced melting and cracking damages on W PFCs by runaway electrons during plasma disruption in EAST provide important references for ITER.
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    • Pub. Date : 2025
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  • 2025

    Structural virology has emerged as the foundation for the development of effective antiviral therapeutics. It is pivotal in providing crucial insights into the three-dimensional frame of viruses and viral proteins at atomic-level or near-atomic-level resolution. Structure-based assessment of viral components, including capsids, envelope proteins, replication machinery, and host interaction interfaces, is instrumental in unraveling the multiplex mechanisms of viral infection, replication, and pathogenesis. The structural elucidation of viral enzymes, including proteases, polymerases, and integrases, has been essential in combating viruses like HIV-1 and HIV-2, SARS-CoV-2, and influenza. Techniques including X-ray crystallography, Nuclear Magnetic Resonance spectroscopy, Cryo-electron Microscopy, and Cryo-electron Tomography have revolutionized the field of virology and significantly aided in the discovery of antiviral therapeutics. The ubiquity of chronic viral infections, along with the emergence and reemergence of new viral threats necessitate the development of novel antiviral strategies and agents, while the extensive structural diversity of viruses and their high mutation rates further underscore the critical need for structural analysis of viral proteins to aid antiviral development. This review highlights the significance of structure-based investigations for bridging the gap between structure and function, thus facilitating the development of effective antiviral therapeutics, vaccines, and antibodies for tackling emerging viral threats.
    • Book : 17(3)
    • Pub. Date : 2025
    • Page : pp.417-417
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  • 2025

    Background: Hodgkin lymphoma (HL) is a B-cell-derived malignancy and one of the most frequent types of lymphoma. The tumour cells typically exhibit multiple genomic alterations together with aberrantly activated signalling pathways, driven by paracrine and/or autocrine modes. SPP1 (alias osteopontin) is a cytokine acting as a signalling activator and has been connected with relapse in HL patients. To understand its pathogenic role, here, we investigated the mechanisms and function of deregulated SPP1 in HL. Methods: We screened public patient datasets and cell lines for aberrant SPP1 expression. HL cell lines were stimulated with SPP1 and subjected to siRNA-mediated knockdown. Gene and protein activities were analyzed by RQ-PCR, ELISA, Western blot, and immuno-cytology. Results: SPP1 expression was detected in 8.3% of classic HL patients and in HL cell line SUP-HD1, chosen to serve as an experimental model. The gene encoding SPP1 is located at chromosomal position 4q22 and is genomically amplified in SUP-HD1. Transcription factor binding site analysis revealed TALE and HOX factors as potential regulators. Consistent with this finding, we showed that aberrantly expressed PBX1 and HOXB9 mediate the transcriptional activation of SPP1. RNA-seq data and knockdown experiments indicated that SPP1 signals via integrin ITGB1 in SUP-HD1. Accordingly, SPP1 activated NFkB in addition to MAPK/ERK which in turn mediated the nuclear import of ETS2, activating oncogenic JUNB expression. Conclusions: SPP1 is aberrantly activated in HL cell line SUP-HD1 via genomic copy number gain and by homeodomain transcription factors PBX1 and HOXB9. SPP1-activated NFkB and MAPK merit further investigation as potential therapeutic targets in affected HL patients.
    • Book : 13(3)
    • Pub. Date : 2025
    • Page : pp.735-735
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  • 2025


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    • Pub. Date : 2025
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  • 2025

    Green innovation, clean energy consumption, and improved energy productivity are crucial for addressing global climate change and combating ecological degradation and are emphasized for their dynamic role in creating a sustainable future. In that sense, this research probed the influences of green innovation, nuclear energy use, and energy productivity on consumption-based carbon emissions in the G-7 economies from 1990 to 2021. Advanced econometric methods were employed, including CS-ARDL for long-run linkage, AMG and CCEMG for robustness, and the DH causality approach. The long-run results specified that green innovation, utilizing nuclear energy resources, and improving energy productivity support decreasing consumption-based carbon emissions. This work recommended implementing the investment in green innovations, expanding nuclear energy consumption, and utilizing energy productivity to lower the existing consumption-based emissions level through policy implementation for G-7 nations.
    • Book : 57(5)
    • Pub. Date : 2025
    • Page : pp.1-42
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  • 2025


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    • Pub. Date : 2025
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  • 2025

    본 논문의 목적은 1979년 중국-베트남 전쟁이 중국 국방현대화에 미친 영향을 분석하는 것이다. 1979년 중국-베트남 전쟁은 중국 인민해방군이 마오쩌둥의 인민전쟁 전략으로 수행한 마지막 전쟁이었다. 중국 인민해방군은 10년 간 베트남 전쟁으로 충분한 실전 경험을 보유한 베트남 인민군에 비해 전술, 전략, 군사 장비, 전투 숙련도에서 열세를 보여주었다. 1979년 2월 17일 중국의 베트남 공격은 베트남 북부 국경도시이자 하노이로 진격할 수 있는 전략적 요충지 랑선을 점령한 3월 5일 철군 선언, 3월 16일 철군이 완료되면서 종결되었다. 1979년 중국-베트남 전쟁이 중국 국방현대화에 미친 영향은 다음과 같다.첫째, 중국은 1979년 중국-베트남 전쟁을 준비하면서 미국, 일본 등 서방 국가들과의 관계를 강화할 수 있었다. 덩샤오핑은 1978년 하반기부터 1979년 1월까지 싱가포르, 일본, 미국을 방문하여 관계를 개선하고 베트남 공격에 관해 논의했다. 미국은 중국의 베트남 공격 전후 소련에 대한 군사 정보를 제공했기 때문에 중국은 소련의 공격을 우려하지 않고 전쟁을 수행할 수 있었다. 미국, 일본, 서방 국가들은 1979년 중국-베트남 전쟁 이후 중국과의 교류 확대, 원조, 경제협력을 추진하였다. 그 결과 중국은 1980년대 경제 성장을 위한 안정적인 외부 환경을 구축할 수 있었다.둘째, 덩샤오핑의 리더십이 강화되었다. 1979년 중국-베트남 전쟁을 지휘한 것은 덩샤오핑이다. 중국은 1978년 12월 11기 3중 전회를 통해 개혁개방 노선을 표방했다. 화궈펑과의 권력 투쟁에서 이제 막 주도권을 잡은 덩샤오핑에게 1979년 2월 베트남 공격은 중요한 결정이었다. 덩샤오핑에게 인민해방군의 전투력은 실망스러웠으나, 베트남 북부 요충지 랑선을 점령하는 데 성공하고 전쟁을 신속히 종결할 수 있었다. 전후 덩샤오핑은 인민해방군 주요 지휘부를 교체함으로써 군에 대한 영향력을 확대할 수 있었다. 이후 100만 감군, 군 구조 개혁 등 국방현대화를 추진할 수 있었다.셋째, 덩샤오핑이 발탁한 류화칭은 중국의 국방현대화, 특히 해군력의 장기 발전을 추진할 수 있었다. 중국 인민해방군은 문화대혁명 기간 동안 군 지휘부가 계급 투쟁에 휘말렸고, 훈련에도 매진할 수 없었으며, 전력의 현대화를 추진하지 못했다. 그 결과 1979년 베트남 공격시 인민해방군의 피해는 막대했다. 덩샤오핑이 발탁한 류화칭은 1982년부터 6년간 해군 사령원으로 재직하였고, 1989년 당 중앙군사위 부주석, 1992년 중앙정치국 상무위원 등 최고위직을 역임할 수 있었다. 류화칭은 국방현대화 정책, 그 중에서도 해군력 발전을 위한 장기 계획을 추진할 수 있었다. 류화칭은 도련선 개념 확립, 원해방어 전략, 핵 잠수함 및 수상함 건조, 항공모함 건조를 위한 연구 개발 작업을 추진할 수 있었다. 1979년 중국-베트남 전쟁 이후 약 45년이 지난 오늘날 중국 해군 전력은 3개 항공모함을 포함 약 360척의 전함을 보유해 양적으로는 미국을 뛰어넘은 것으로 평가받고 있다. 남중국해를 넘어 태평양 진출을 시도하고 있는 중국의 해군 전력은 서해를 마주하고 있는 우리에게 구체적이고 장기적인 해양 전략 수립의 필요성, 정치지도자 및 국민에 대한 설득 등 측면에서 깊은 성찰의 사례가 되고 있다.
    • Pub. Date : 2025
    • Page : pp.123-148
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