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Nitrogen addition promotes soil carbon accumulation globally

Science China Life Sciences 2025年第1期68卷 284-293页

作者： Xuemei yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling zhu Chengjun Ji Biao zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

关键词： meta-analysis nitrogen enrichment soil organic carbon carbon accumulation carbon stability

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脾硬化性血管瘤样结节性转化6例临床病理分析

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诊断病理学杂志 2013年第10期20卷 593-595,599页

作者：颜红柱李维卿刘惠敏何金余宏宇第二军医大学附属长征医院病理科上海200003

目的探讨脾硬化性血管瘤样结节性转化(SANT)的临床病理表现、诊断与鉴别诊断。方法对6例SANT的临床、组织病理学和免疫组化特征进行观察并文献复习。结果 SANT主要表现为局部有多个血管瘤样结节,结节周围可有增生的纤维组织包绕,结节中... 详细信息

目的探讨脾硬化性血管瘤样结节性转化(SANT)的临床病理表现、诊断与鉴别诊断。方法对6例SANT的临床、组织病理学和免疫组化特征进行观察并文献复习。结果 SANT主要表现为局部有多个血管瘤样结节,结节周围可有增生的纤维组织包绕,结节中心为裂隙样、不规则的血管腔,内衬肥胖的内皮细胞,管腔周围可见梭形细胞和卵圆形细胞,结节之间亦可见密集的梭形细胞和卵圆形细胞,有淋巴细胞、浆细胞和组织细胞浸润。免疫组化:血管样腔隙内皮细胞显示3种不同的免疫组化表型CD34+/CD31+/CD8-、CD34-/CD31+/CD8+和CD34-/CD31+/CD8-,结节内梭形细胞CD31、SMA和CD68(+),结节间梭形细胞和卵圆细胞SMA和CD68(+)。结论 SANT是一种少见的脾良性病变,有特征性的临床病理表现,预后良好,尤其需要与脾的交界性或恶性肿瘤鉴别。

关键词：脾硬化性血管瘤样结节性转化临床病理免疫组化

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Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang Qing Shi Guofan Zhang Yuxuan zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

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Recent advances in radical-mediated fluorination through C-H and C-C bond cleavage

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Science China Chemistry 2017年第2期60卷 214-222页

作者： hong yan Chen zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou 215123 China

The C-H and C-C bonds are abundant in organic compounds,yet generally inert in chemical ***,direct functionalization of inert chemical bonds remains *** fluorine-containing compounds are of special interest for their uses in medicinal *** fluorination of C-H and C-C bonds undoubtedly represents one of the most ideal and attractive approaches to incorporate fluorine atom into complex ***,we summarize the recent advances in radical-mediated C-H and C-C bond *** types of transformations are discussed:(1)direct C-H abstraction/fluorination of alkanes;(2)decarboxylative fluorination of alkyl carboxylic acids;(3)ring-opening fluorination.

关键词： fluorination C-H functionalization decarboxylation ring-opening radical

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SEFormer:A Lightweight CNN-Transformer Based on Separable Multiscale Depthwise Convolution and Efficient Self-Attention for Rotating Machinery Fault Diagnosis

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Computers, Materials & Continua 2025年第1期82卷 1417-1437页

作者： hongxing Wang Xilai Ju Hua zhu Huafeng Li State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China School of Computer Science and Engineering Nanyang Technological UniversitySingapore639798Singapore

Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain ***,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis ***,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault ***,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative *** complexity results in high computational costs and limited industrial *** tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault ***,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration ***,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global ***,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and *** study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment.

关键词： CNN-Transformer separable multiscale depthwise convolution efficient self-attention fault diagnosis

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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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Defect Engineering with Rational Dopants Modulation for High‑Temperature Energy Harvesting in Lead‑Free Piezoceramics

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Nano-Micro Letters 2025年第3期17卷 87-101页

作者： Kaibiao Xi Jianzhe Guo Mupeng Zheng Mankang zhu Yudong Hou Key Laboratory of Advanced Functional Materials Ministry of EducationCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124People’s Republic of China

High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless ***,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported ***,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese *** to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese *** HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.

关键词： Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester

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辅食喂养热点问题及相关研究进展

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中国妇幼健康研究 2017年第5期28卷 612-615页

作者：冯超关宏岩朱宗涵首都儿科研究所北京100020

科学合理的辅食喂养不仅可以保证婴幼儿良好的生长发育,而且有利于婴幼儿形成健康的饮食习惯。世界卫生组织在2002年提出了婴幼儿全球喂养策略,建议婴幼儿应纯母乳喂养至6个月,然后继续母乳喂养的同时开始添加辅食。2007年国家卫计委出... 详细信息

科学合理的辅食喂养不仅可以保证婴幼儿良好的生长发育,而且有利于婴幼儿形成健康的饮食习惯。世界卫生组织在2002年提出了婴幼儿全球喂养策略,建议婴幼儿应纯母乳喂养至6个月,然后继续母乳喂养的同时开始添加辅食。2007年国家卫计委出台的《婴幼儿喂养策略》提出了相同的建议。随着婴幼儿辅食喂养与健康相关研究的不断深入,世界各国婴幼儿辅食喂养指南也在不断完善和更新。该文对欧美、澳大利亚、日本和我国最新发布的婴幼儿辅食喂养指南中辅食添加时间、顺序及种类、铁的补充和食物过敏等热点问题的最新建议与相关研究进行综述,为基层开展婴幼儿辅食喂养指导提供参考。

关键词：辅食喂养指南婴幼儿

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Exploring the potential of extrachromosomal DNA as a novel oncogenic driver

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Science China Life Sciences 2025年第1期68卷 144-157页

作者： Huanbo zhu Longtao Huangfu Junbing Chen Jiafu Ji Xiaofang Xing Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Division of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute Department of Gastrointestinal Cancer Center Peking University Cancer Hospital & Institute Department of Liver Surgery & Transplantation Liver Cancer InstituteZhongshan HospitalFudan University Key Laboratory of Carcinogenesis and Cancer Invasion Ministry of Education State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDivision of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute

Extrachromosomal DNA(ecDNA) is a form of circular DNA mostly found in tumor cells. Unlike the typical chromosomal DNA, ecDNA is circular, self-replicating, and carries complete or partial gene fragments. Although ecDNA occurrence remains a rare event in cancer, recent studies have shown that oncogene amplification on ecDNA is widespread throughout many types of cancer, implying that ecDNA plays a central role in accelerating tumor evolution. ecDNA has also been associated with increased tumor mutation burden, chromosomal instability, and even tumor microenvironment remodeling. ecDNA may be crucial in influencing tumor heterogeneity, drug sensitivity,oncogenic senescence, and tumor immunogenicity, leading to a worsening prognosis for tumor patients. In this way, several clinical trials have been conducted to investigate the importance of ecDNA in clinical treatment. In this review, we summarize the biogenesis, characteristics, and current research methods of ecDNA, discuss the vital role of ecDNA-caused tumor heterogeneity in cancers, and highlight the potential role of ecDNA in cancer therapy.

关键词： extrachromosomal DNA cancer therapy tumor heterogeneity drug resistance tumor evolution

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Microstructure and properties of mullite-based porous ceramics produced from coal fly ash with added Al_2O_3

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 309-315页

作者： Jian-bin zhu hong yan Department of Materials Processing Engineering School of Mechanical Electrical EngineeringNanchang University School of Mechanical Electrical Engineering Nanchang Institute of Technology

Using coal fly ash slurry samples supplemented with different amounts of Al2O3, we fabricated mullite-based porous ceramics via a dipping-polymer-replica approach, which is a popular method suitable for industrial application. The microstructure, phase composition, and compressive strength of the sintered samples were investigated. Mullite was identified in all of the prepared materials by X-ray diffraction analysis. The microstructure and compressive strength were strongly influenced by the content of Al2O3. As the Al/Si mole ratio in the starting materials was increased from 0.84 to 2.40, the amount of amorphous phases in the sintered microstructure decreased and the compressive strength of the sintered samples increased. A further increase in the Al2O3content resulted in a decrease in the compressive strength of the sintered samples. The mullite-based porous ceramic with an Al/Si molar ratio of 2.40 exhibited the highest compressive strength and the greatest shrinkage among the investigated samples prepared using coal fly ash as the main starting material. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Aluminum Amorphous materials Ceramic materials Coal Coal ash Fly ash Microstructure Mullite Porous materials Silicate minerals Sintering Strength of materials X ray diffraction analysis

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