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Rock magnetic property of gravity core CSH1 from the northern Okinawa Trough and the effect of early diagenesis

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Acta Oceanologica Sinica 2007年第5期26卷 54-65页

作者： GE Shulan SHI Xuefa WU Yonghua LEE Tehquei xiong yingqian SAITO Yoshiki Marine Sedimentation and Environmental Geology Key Laboratory of State Oceanic Administration First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Earth Sciences Taipei China Geology Survey of Japan Tsukuba 306 - 8567 Japan

Detailed rock magnetic investigations were undertaken at 2 -4 cm interval for the gravity core CSHI （with a length of 17.36 m） from the northern Okinawa Trough. Time-scale of the core was constructed by two characteristic tephras and foraminferal assemblages, indicating an age of 50 ka for the bottom of the core. Except for three tephras and abrupt decrease in surface, there are little changes in all kinds of rock magnetic parameters that can be correlated to the climate change for the last 50 ka. Different from the common sediments, most S-ratios （S equals the negative ratio of IRM-0.3T to SIRM, which is an indicator of low coercivity content） of the sediments are smaller than 0. 9, which implies a substantial amount of magnetic minerals with high coercivity. The existence of iron sulphide （ greigite or pyrrhotite） is revealed by representative susceptibility - temperature curves showing 200 350 ℃ Curie temperature in addition to 580 ℃ of magnetite, and also by awful smell during heating and dark heating products. Both the occurrence of authigenic iron sulphide and quick decrease of magnetic parameters near the surface clearly show that sediments from Core CSHI have undergone early diagenesis. The featureless magnetic changes of the whole core except for three tephras mean that the post-depositonal alteration is so strong that most original signals have been destroyed. For the same reason, the organic matter in sediment and sulphate in pore water must have been consumed along with dissolution, precipitation of iron and manganese happening sequencially during the redox reaction series. Great caution must be taken when using these altered chemical parameters for the interpretation of climatic changes.

关键词： northern Okinawa Trough gravity core of CSHI rock magnetic property characteristic tephra early diagenesis

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预制拼装混凝土双柱墩抗震性能试验

沈阳建筑大学学报（自然科学版） 2023年第3期39卷 492-499页

作者：李航刘朵熊英倩张建东南京工业大学土木工程学院江苏南京211816 在役长大桥梁安全与健康国家重点实验室江苏南京211112 苏交科集团股份有限公司江苏南京210019

目的研究预制混凝土双柱墩的抗震性能,为该类桥墩抗震设计及工程应用提供参考。方法开展预制装配式双柱墩和现浇双柱墩往复加载试验,观察试验过程中两者的裂缝开展和破坏形态,并对滞回曲线、残余位移、刚度、累计耗能和延性等参数进行... 详细信息

目的研究预制混凝土双柱墩的抗震性能,为该类桥墩抗震设计及工程应用提供参考。方法开展预制装配式双柱墩和现浇双柱墩往复加载试验,观察试验过程中两者的裂缝开展和破坏形态,并对滞回曲线、残余位移、刚度、累计耗能和延性等参数进行对比。结果与现浇墩底部裂缝较为均匀的状况相比,预制双柱墩墩底灌浆套筒位置接缝张开较为明显,预制双柱墩与现浇双柱墩滞回曲线均较为饱满,具有良好耗能能力;预制双柱墩峰值承载力和极限位移分别为现浇墩对应值的91.6%和88.4%,总体耗能性能稍弱于现浇双柱墩。结论预制混凝土双柱墩抗震性能指标与现浇双柱墩相比,差值均为10%左右,没有明显差异;预制混凝土双柱墩具有良好的整体性和抗震性能。

关键词：预制混凝土双柱墩抗震性能往复荷载滞回曲线峰值承载力

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Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei xiong Xuan Ye Hongzhang Cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Adaptive-basis decomposition-based low-rank network for efficient non-uniform motion deblurring

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Optoelectronics Letters 2025年第1期21卷 43-50页

作者： CHEN Lei xiong Qingbo ZHANG Wei LI Runde School of Software Henan University School of Applied Technology China University of Labor Relations

In this study, we present a unified sparsity-driven framework that significantly enhances motion deblurring performance by integrating two key components: a custom-designed dataset and a low-rank module(LRM). This framework leverages the inherent sparsity of per-pixel blur kernels to bolster both deblurring accuracy and model interpretability. Firstly, we propose an adaptive-basis decomposition-based deblurring(ADD) approach, which constructs a tailored training dataset to enhance the generalization capacity of the deblurring network. The ADD framework adaptively decomposes motion blur into sparse basis elements, effectively addressing the intricacies associated with non-uniform blurs. Secondly, an LRM is proposed to improve the interpretability of deblurring models as a plug-and-play module, primarily designed to identify and harness the intrinsic sparse features in sharp images. A series of ablation studies have been conducted to substantiate the synergistic advantages of combining the proposed ADD with the LRM for overall improvement in deblurring efficacy. Subsequently, we empirically demonstrate through rigorous experimentation that incorporating the LRM into an existing Uformer network leads to substantial enhancement in reconstruction performance. This integration yields a sparsity-guided low-rank network(SGLRN). Operating under the overarching principle of sparsity, SGLRN consistently outperforms state-of-the-art methods across multiple standard deblurring benchmarks. Comprehensive experimental results, assessed through quantitative metrics and qualitative visual evaluations, provide compelling evidence of its effectiveness. The overall deblurring results are available at Google Drive.

关键词： Image enhancement

AZD1775 synergizes with SLC7A11 inhibition to promote ferroptosis

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Science China Life Sciences 2025年第1期68卷 204-218页

作者： Chen xiong Hong Ling Yingdan Huang Hanzhi Dong Bangxiang Xie Qian Hao Xiang Zhou Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences Fudan University Department of Oncology Shanghai Medical CollegeFudan University Department of Breast Surgery Fudan University Shanghai Cancer CenterFudan University Department of Oncology First Affiliated Hospital of Nanchang University Beijing Institute of Hepatology Beijing Youan HospitalCapital Medical University Beijing Engineering Research Center for Precision Medicine and Transformation of Hepatitis and Liver Cancer Key Laboratory of Breast Cancer in Shanghai Fudan University Shanghai Cancer CenterFudan University Shanghai Key Laboratory of Medical Epigenetics International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology)Institutes of Biomedical SciencesFudan University

Tumor suppressor p53-mediated cell cycle arrest and DNA damage repair may exert cytoprotective effects against cancer therapies, including WEE1 inhibition. Considering that p53 activation can also lead to multiple types of cell death, the role of this tumor suppressor in WEE1 inhibitor-based therapies remains disputed. In this study, we reported that nucleolar stress-mediated p53 activation enhanced the WEE1 inhibitor AZD1775-induced ferroptosis to suppress lung cancer growth. Our findings showed that AZD1775 promoted ferroptosis by blocking cystine uptake, an action similar to that of Erastin. Meanwhile, inhibition of WEE1 by the WEE1 inhibitors or si RNAs induced compensatory upregulation of SLC7A11, which conferred resistance to ferroptosis. Mechanistically, AZD1775 prevented the enrichment of H3K9me3, a histone marker of transcriptional repression, on the SLC7A11 promoter by repressing the expression of the histone methyltransferase SETDB1, thereby enhancing NRF2-mediated SLC7A11 transcription. This finding was also validated using the H3K9me3 inhibitor BRD4770. Remarkably, we found that the nucleolar stress-inducing agent Actinomycin D(Act. D) inhibited SLC7A11 expression by activating p53, thus augmenting AZD1775-induced ferroptosis. Moreover, the combination of AZD1775 and Act. D synergistically suppressed wild-type p53-harboring lung cancer cell growth both in vitro and in vivo. Altogether, our study demonstrates that AZD1775 promotes ferroptosis by targeting cystine uptake but also mediates the adaptive activation of SLC7A11 through the WEE1-SETDB1 cascade and NRF2-induced transcription, and inhibition of SLC7A11 by Act. D boosts the anti-tumor efficacy of AZD1775 by enhancing ferroptosis in cancers with wild-type p53.

关键词： p53 NRF2 SLC7A11 WEE1 AZD1775 ferroptosis nucleolar stress

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong Zhang Zhiying Chen Yinyi xiong Qin Zhou Ling-Qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

CO2-mediated bicarbonate conversion to concentrated formate in a CEM-based electrolyzer

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Journal of Energy Chemistry 2025年第1期100卷 605-611页

作者： Haocheng xiong Donghuan Wu Haonan Li Andrew Li Qikun Hu Siyao Song Bingjun Xu Qi Lu State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University College of Chemistry and Molecular Engineering Peking University Ordos Laboratory

Renewable energy-driven bicarbonate conversion to valuable chemicals presents an attractive strategy for mitigating CO2emissions,as bicarbonate can be efficiently generated from the capture of atmospheric CO2using alkaline solutions with reactive *** this work,we present a CO2-mediated bicarbonate conversion to pure formate using a cation exchange membrane-based electrolyzer with a 25 cm2electrode *** electrolysis achieved selectivities exceeding 75%for formate at a total current of 2.5 A,achieving formate concentrations up to 1.2 M and yields as high as 95%over extended *** techno-economic assessment confirmed the economic viability of the process,highlighting the potential for bicarbonate electrolysis as a sustainable method for producing valuable chemicals.

关键词： Electrocatalysis Techno-economic assessments Electrochemistry Flow electrolyzer

GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

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Science China(Information Sciences) 2025年第1期68卷 145-158页

作者： Wei JU Yiyang GU Zhengyang MAO Ziyue QIAO Yifang QIN Xiao LUO Hui xiong Ming ZHANG School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

关键词： graph representation learning graph neural networks graph contrastive learning graph augmentations graph pooling