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Shear weakening behavior at the surface of structural plane of rock

Yantu Lixue/Rock and Soil Mechanics 2020年 41卷 19-29页

作者： He, liu Zhao, Zhi-Ming Wu, Guang liu, di-yi Faculty of Geosciences and Environmental Engineering Southwest Jiaotong University Chengdu 611756 China

Based on a series of direct shear test results of structural planes of similar materials of rock mass, the initial morphology of different structural planes Z2, structural surface wall strength JCS and normal stress σn on the shear weakening and failure of structural surfaces are studied under different shear displacement conditions by applying the three-dimensional scanning identification technique. The results show that the surface damage coefficient (N) of the joint surfaces with higher Z2(initial), JCS and σn increases significantly at different shear displacements with the continuous increase of shear displacement. Structural surfaces with a much higher JCS value are dominated by brittle failure, while structural surfaces with a smaller JCS value are dominated by wear-out failure. During the shear process, the weakening of the structural surface morphology is caused by the "shear effect" of the surface protrusion, and also the "filling effect" of the depressed area of the structural plane. Based on the degradation rate of the morphology factor of structural plane Z2(δ) at different shear displacement, the degradation process of joint surface was classified into three stages with the shear displacement: the initial degradation stage, rapid degradation stage, and constant degradation stage. With the increase of Z2(initial), JCS and σn, the segmentation characteristics of degradation of structural planes become much more obvious, and the transformation process of three stages has an accelerating trend. An empirical model of joint surface morphology degradation under the influence of different factors is proposed through the regression analysis. The results indicate that the accurate tracking on the weakening characteristics of the structural surface morphology during the shearing process is beneficial to study the evolution of mechanical properties of the structural surfaces during the shearing process. © 2020, Science Press. All right reserved.

关键词： Surface morphology

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Domain generalization with semi-supervised learning for people-centric activity recognition

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Science China(Information Sciences) 2025年第1期68卷 171-188页

作者： Jing liu Wei ZHU di LI Xing HU Liang SONG Academy for Engineering & Technology Fudan University Shanghai East-bund Research Institute on Networking Systems of AI School of Optoelectronic Information and Computer Engineering University of Shanghai for Science & Technology

People-centric activity recognition is one of the most critical technologies in a wide range of real-world applications,including intelligent transportation systems, healthcare services, and brain-computer interfaces. Large-scale data collection and annotation make the application of machine learning algorithms prohibitively expensive when adapting to new tasks. One way of circumventing this limitation is to train the model in a semi-supervised learning manner that utilizes a percentage of unlabeled data to reduce the labeling burden in prediction tasks. Despite their appeal, these models often assume that labeled and unlabeled data come from similar distributions, which leads to the domain shift problem caused by the presence of distribution gaps. To address these limitations, we propose herein a novel method for people-centric activity recognition,called domain generalization with semi-supervised learning(DGSSL), that effectively enhances the representation learning and domain alignment capabilities of a model. We first design a new autoregressive discriminator for adversarial training between unlabeled and labeled source domains, extracting domain-specific features to reduce the distribution gaps. Second, we introduce two reconstruction tasks to capture the task-specific features to avoid losing information related to representation learning while maintaining task-specific consistency. Finally, benefiting from the collaborative optimization of these two tasks, the model can accurately predict both the domain and category labels of the source domains for the classification task. We conduct extensive experiments on three real-world sensing datasets. The experimental results show that DGSSL surpasses the three state-of-the-art methods with better performance and generalization.

关键词： activity recognition deep learning domain generalization semi-supervised learning adversarial training

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美国FDA药物临床试验研发主体合规检查信息公开情况的介绍和启示

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中国新药杂志 2024年第2期33卷 124-130页

作者：刘艺迪何辉周刚国家药品监督管理局药品审评中心北京100076

美国FDA在药物临床试验研发主体合规检查信息的公开及数据库建设方面有着较为成熟的经验.本文对美国FDA管理和公开药物临床试验研发主体合规检查信息的方式进行系统介绍,并结合我国监管现状,为我国药品监管部门建立规范化的合规检查信... 详细信息

美国FDA在药物临床试验研发主体合规检查信息的公开及数据库建设方面有着较为成熟的经验.本文对美国FDA管理和公开药物临床试验研发主体合规检查信息的方式进行系统介绍,并结合我国监管现状,为我国药品监管部门建立规范化的合规检查信息数据库、提高药物临床试验研发主体合规检查信息的可及性提出建议.

关键词：药物临床试验合规检查临床研究者药物临床试验机构

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Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： di-Chao Chen Xie liu Changqing Xu Da-Jian Wu ying Cheng Xiao-Jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

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监管科学视角下基于风险启动药品注册临床试验现场核查的新思考

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中国新药杂志 2024年第8期33卷 756-760页

作者：何辉刘艺迪周刚国家药品监督管理局药品审评中心北京100061

为合理利用药品注册核查监管资源、加强对于药品研发过程的监管,我国药品监管机构根据我国医药产业发展现状,并参考国外药品监管实践建立了“基于风险”和“基于技术审评工作需要”的药品注册核查启动模式,提升了注册核查的针对性和效能... 详细信息

为合理利用药品注册核查监管资源、加强对于药品研发过程的监管,我国药品监管机构根据我国医药产业发展现状,并参考国外药品监管实践建立了“基于风险”和“基于技术审评工作需要”的药品注册核查启动模式,提升了注册核查的针对性和效能,优化了我国药品注册管理体系,在一定程度上促进了医药产业的高质量发展。但在监管实践探索中仍然存在风险因素识别不够全面、风险模型构建考量因素不够深入等问题。本文分析了国内外药品监管机构启动药品注册临床试验现场检查的工作模式,并基于我国监管工作现状和经验,为优化药品注册临床试验现场核查启动工作提出几点建议和参考。

关键词：药品注册核查风险因素药品监管

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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2982-2997页

作者： Hongli Li Jianhua Huang di Zhao Lemei Zhu Zheyu Zhang Min yi Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Metabolic diseases ChangshaHunan ProvinceChina Hunan Academy of Chinese Medicine ChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut *** aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease *** do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of ***-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 ***,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 *** findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

关键词： Alzheimer’s disease APP/PS1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis

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PI3K/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

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Neural Regeneration Research 2025年第10期20卷 2758-2775页

作者： Tianlong liu Xiaolin Li Xiaowei Zhou Wei Chen Aidong Wen Minna liu yi ding Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Pharmacy The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina Department of Pharmacy The 944 Hospital of Joint Logistics Support Forces of Chinese PLAJiuquanGansu ProvinceChina Department of Nephrology The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic *** a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from *** article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling *** key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic *** investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

关键词： apoptosis autophagy inflammation ischemic stroke neuroprotection oxidative stress pathogenesis phosphatidylinositol 3-kinase protein kinase B therapeutics

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Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan Shi Qun yi Yao liu yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction

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复杂风场环境下的多旋翼无人机编队故障检测方法

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吉林大学学报（工学版） 2023年第3期53卷 823-831页

作者：王小艺刘迪一于家斌何卓昀赵峙尧北京工商大学人工智能学院北京100048

针对多旋翼无人机编队故障检测研究的不足,提出了一种在复杂风场飞行环境下多旋翼无人机编队的故障检测方法。结合多旋翼动态行为和风扰动建模,基于卡尔曼滤波算法对编队中各多旋翼的状态变量进行实时估计,并通过概率统计的方法提取故... 详细信息

针对多旋翼无人机编队故障检测研究的不足,提出了一种在复杂风场飞行环境下多旋翼无人机编队的故障检测方法。结合多旋翼动态行为和风扰动建模,基于卡尔曼滤波算法对编队中各多旋翼的状态变量进行实时估计,并通过概率统计的方法提取故障特征,进而建立辨识器模型进行故障检测,最终得到编队中的故障机辨识结果。在仿真验证环节,搭建了基于RflySim飞行仿真平台的湍流风与有色阵风叠加的复杂风场模型,分别对多旋翼的螺旋桨、加速度计、GPS、电池进行故障注入和编队飞行模拟,通过多组仿真验证了本文方法的有效性。

关键词：故障检测多旋翼无人机编队复杂风场卡尔曼滤波 RflySim平台

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Electrocatalytic cleavage of a lignin β-O-4 model compound and coupling with nitrogen-containing aromatics using Prussian blue analogue-derived nickel–cobalt spinel

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Journal of Energy Chemistry 2025年第1期100卷 628-636页

作者： yi Qi Xueying Chen Bowen liu Xuliang Lin Xueqing Qiu Yanlin Qin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light Industry Guangdong University of Technology Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Guangdong Basic Research Center of Excellence for Ecological Security and Green Development Guangdong University of Technology

Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great *** demonstrate the targeted synthesis and cation modulation of NiCo2O4spinel nanoboxes,synthesized via cation exchange and calcination *** catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and *** catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as *** porous architecture and polymetallic composition of the NiCo2O4spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for *** innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT *** work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.

关键词： Spinel Biomass valorization Electrocatalysis Lignin oxidation Coupling

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