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Monazite and xenotime U-Th-Pb geochronology by ion microprobe:dating highly fractionated granites at Xihuashan tungsten mine,SE China

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Monazite and xenotime U-Th-Pb geochronology by ion microprob...

心脏MR首过灌注成像用于评价接受化疗的妇科恶性肿瘤病人的心肌微血管功能

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： q.l.li X.H.li Z.W.lan C.l.Guo Y.N.Yang Y.liu G.q.Tang State Key laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Institute of Mineral Resources Chinese Academy of Geological Sciences University of Chinese Academy of Sciences

Zircon,monazite,and xenotime have proven to be valuable chronometers for various geological processes due to their commonly high-U-Th and low common Pb ***,zircons that have crystallized in highly fractionated granites often have such high-U contents that radiation damage can lead to scattered U-Pb ages when measured with secondary ion mass spectrometry(SIMS). In this study,monazite and xenotime were separated from a number of highly fractionated granites at the Xihuashan tungsten mine,Southeast China,for alternative dating methods by *** monazite analysis,obvious excess Pb signal(mainly from interference of ThNdO) was observed in high-Th(>2 wt%) monazite,which hinders Pb-based common Pb corrections. A Pb-based common Pb correction method was used *** employing power law relationships between Pb/U versus UO/U,Pb/Th versus ThO/Th and suitable exponentials,monazites with TI1O2 contents in the range of～3-19%do not exhibit this matrix *** SIMS U-Pb ages and Th-Pb ages of three phases of Xihuashan granite samples were consistent with each other and yielded dates of 158.7±0.7,158.0±0.7,and 156.9±0.7 Ma,*** does show marked matrix effects due to variations of U,Th,and Y[or total rare earth element(REE),referred as ZREE hereafter]contents. Suitable correction factors require end-member standards with extremely high or low U,Th,and Y(or ZREE) contents. No excess Pb was observed,indicating that the Pb-based common Pb correction method is feasible. Independent Pb/Pb ages can be obtained,although multi-collector mode is necessary to improve *** main difficulties with dating xenotime are when high-Th (U) mineral inclusions are *** can identify when this occurs,however,by comparing the measured UO/U and ThO/Th with those in xenotime *** xenotime samples from the first phase of Xihuashan granite yielded a weighted mean 207Pb/Pb date of 159.5±4.4 Ma(MSWD = 1.0) and a Pb/U date of 159.4±0.9 Ma(MSW

关键词： SIMS Monazite Xenotime Zircon U-Pb dating Highly fractionated granites

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国际医学放射学杂志 2022年第6期45卷 745-745页

作者： M.X.Yang q.l.li D.q.Wang l.Ye K.M.li X.J.lin 魏锋

摘要目的癌症化疗有可能增加心肌缺血的风险。本研究通过心脏 MR（CMR）首过灌注成像评价接受化疗的妇科恶性肿瘤病人的心肌微血管功能。方法前瞻性纳入 81 例接受

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Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia

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Neural Regeneration Research 2025年第3期20卷 873-886页

作者： Ying Wang Xiang Zhang Henrik Biverstål Nicolas GBazan Shuai Tan Nailin li Makiko Ohshima Marianne Schultzberg Xiaofei li Department of Neurobiology Care Sciences&SocietyDivision of NeurogeriatricsKarolinska InstitutetStockholmSweden Department of Neurology Neuroscience CenterThe First Hospital of Jilin UniversityChangchunJilin ProvinceChina Department of Physiology and Pharmacology Karolinska InstitutetStockholmSweden Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Neuroscience Center of Excellence Louisiana State UniversityNew OrleansLAUSA Department of Medicine SolnaClinical Pharmacology GroupKarolinska University HospitalStockholmSweden

Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β maresin microglia monocyte neuroinflammation resolution RNA-sequencing specialized pro-resolving lipid mediator

Interpretable Machine learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： SHI Yuqiong li Jingyi ZHANG Yang li li Key laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data were collected,and a new database of compressive strength of PFGC was *** order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative *** five machine learning models all showed good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** two models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

Constraints on holographic qCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of qCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice qCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order qCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array qCD phase transition gravitational waves primordial black holes

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao Yuan li Yu Wang Key laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RqD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei Xiao qianqian Gu Haoyu li Mengyao li Yude Wang National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemistry and Chemical Engineering Hainan University College of Chemical Engineering Fuzhou University Yunnan Key laboratory of Carbon Neutrality and Green low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2serving as a cathodic armor extends the cycling life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： Zinc alloys

Targeting epigenetic mechanisms in amyloid-β-mediated Alzheimer’s pathophysiology:unveiling therapeutic potential

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Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie Z.li Nagendran Ramalingam Shaomin li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alzheimer’s disease is a prominent chronic neurodegenerative condition characterized by a gradual decline in memory leading to *** evidence suggests that Alzheimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alzheimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alzheimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alzheimer’s *** suggest that addressing Alzheimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alzheimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury

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Neural Regeneration Research 2025年第10期20卷 2807-2822页

作者： Xizi Song Ruixin li Xiaolei Chu qi li Ruihua li qingwen li Kai-Yu Tong Xiaosong Gu Dong Ming Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Haihe laboratory of Brain-Machine Interface and Human-Machine Fusion TianjinChina Department of Rehabilitation Tianjin University Tianjin HospitalTianjinChina Department of Hand Microsurgery Tianjin University Tianjin HospitalTianjinChina School of Exercise and Health Tianjin University of SportTianjinChina Department of Biomedical Engineering the Chinese University of Hong KongHong Kong Special Administrative RegionChina

Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and *** on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target *** has led to restrictions on current therapeutic *** this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target *** peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal *** nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury *** damage to target organs can occur,including skeletal muscle atrophy and sensory receptor *** then provide a brief review of the research advances in therapeutic approaches to peripheral nerve *** main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical ***,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ ***,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.

关键词： central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach