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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang li Yu liu xiao-xiao ling li-Guang Wu li Yang Lan Yang Bo Yang Yong-Gang Zhao Xian-Hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Fast spreading of surface ozone in both temporal and spatial scale in Pearl River Delta

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Journal of Environmental Sciences 2024年第3期137卷 540-552页

作者： Tianhui Cao Haichao Wang Lei li xiao Lu Yiming liu Shaojia Fan School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationZhuhai 519082China

Surface ozone(O_(3))is a major air pollutant and draw increasing attention in the Pearl River Delta(PRD),China.Here,we characterize the spatial-temporal variability of ozone based on a dataset obtained from 57 national monitoring sites during 2013-2019.Our results show that:(1)the seasonal difference of ozone distribution in the inland and coastal areas was significant,which was largely affected by the wind pattern reversals related to the East Asian monsoon,and local ozone production and destruction;(2)the daily maximum 8hr average(MDA8 O_(3))showed an overall upward trend by 1.11 ppbv/year.While the trends in the nine cities varied differently by ranging from-0.12 to 2.51 ppbv/year.The hot spots of ozone were spreading to southwestern areas from the central areas since 2016.And ozone is becoming a year-round air pollution problem with the pollution season extending to winter and spring in PRD region.(3)at the central and southwestern PRD cities,the percentage of exceedance days from the continuous type(defined as≥3 days)was increasing.Furthermore,the ozone concentration of continuous type was much higher than that of scattered exceedance type(line since2017,the total number of exceedance days during the continuous type is increasing.These results indicate that it is more difficult to eliminate the continuous exceedance than the scatter pollution days and highlight the great challenge in mitigation of O_(3)pollution in these cities.

关键词： Surface ozone pollution Ozone trend Spatial and temporal variability Pearl River Delta Pollution mitigation

Mapping the intellectual structure and emerging trends for the application of nanomaterials in gastric cancer:A bibliometric study

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2181-2199页

作者： Bo-Na liu xiao-li Gao Ying Piao Department of Oncology General Hospital of Northern Theater CommandShenyang 110015Liaoning ProvinceChina

BACKGROUND Recent reviews have outlined the main nanomaterials used in relation to gastrointestinal tumors and described the basic properties of these materials.However,the research hotspots and trends in the application of nanomaterials in gastric cancer(GC)remain obscure.AIM To demonstrate the knowledge structure and evolutionary trends of research into the application of nanomaterials in GC.METHODS Publications related to the application of nanomaterials in GC were retrieved from the Web of Science Core Collection for this systematic review and bibliometric study.VOSviewer and CiteSpace were used for bibliometric and visualization analyses.RESULTS From 2000 to 2022,the application of nanomaterials in GC developed rapidly.The keyword co-occurrence analysis showed that the related research topics were divided into three clusters:(1)The application of nanomaterials in GC treatment;(2)The application and toxicity of nanomaterials in GC diagnosis;and(3)The effects of nanomaterials on the biological behavior of GC cells.Complexes,silver nanoparticles,and green synthesis are the latest high-frequency keywords that represent promising future research directions.CONCLUSION The application of nanomaterials in GC diagnosis and treatment and the mechanisms of their effects on GC cells have been major themes in this field over the past 23 years.

关键词： Nanomaterials Gastric cancer Bibliometrics Drug delivery VOSviewer CiteSpace Systematic review

MP-3 microperimeter in early primary open angle glaucoma with a new pattern

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 861-868页

作者： Shuang liang li-Tao Wang xiao-li liu Jia-liang Duan Dan-Yan liu Department of Ophthalmology of the Second Hospital of Hebei Medical University Shijiazhuang 050000Hebei ProvinceChina Department of Ophthalmology Shijiazhuang People’s HospitalShijiazhuang 050000Hebei ProvinceChina

AIM:To investigate macular microperimetry in patients with early primary open angle glaucoma(POAG)using a new custom-made pattern,and analyze the characteristics of macular sensitivity.METHODS:This case-control study included 38 patients with POAG,who were divided into pre-perimetric glaucoma(18 eyes of 18 patients),early-stage(20 eyes of 20 patients),and control(20 eyes of 20 patients)groups.All subjects underwent standard 24-2 humphrey visual field test.An MP-3 microperimeter with a new custom-made pattern(28 testing points distributed in four quadrants,covering the central 10°of the retina)was used to evaluate macular sensitivity.Ganglion cell complex(GCC)thicknesses were examined using an RS-3000 Advance OCT system.The features of structure and function were analysed per quadrant.RESULTS:The pre-perimetric glaucoma group had significantly lower inferior hemifield macular sensitivity compared to controls(Plier than conventional perimetry,particularly in pre-perimetric glaucoma cases in which it might be undetectable by conventional methods.The new custom-made pattern may improve th

关键词： early primary open angle glaucoma macular sensitivity microperimetry optical coherence tomography ganglion cell complex

Impacts of Water-Sediment Regulation Scheme on Chromophoric Dissolved Organic Matter in the Lower Yellow River

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Journal of Ocean University of China 2024年第2期23卷 455-466页

作者： liu xiao JIANG Xueyan liu Qian SUI Juanjuan ZOU li Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China School of Earth Sciences University of BristolBristolBS81RJUK North China Sea Environmental Monitoring Center State Oceanic AdministrationQingdao 266033China Key Laboratory of Ecological Prewarning Protection and Restoration of Bohai SeaMinistry of Natural ResourcesQingdao 266033China Key Laboratory of Marine Environment and Ecology of Ministry of Education Ocean University of ChinaQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China

As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water quality.Chromophoric dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human activities.Here,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during WSRS.In addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM compositions.Under the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS period.Sediment resuspension inhibits microbial activities and reduces the production of autochthonous CDOM.Overall,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment.

关键词： chromophoric dissolved organic matter(CDOM) water-sediment regulation scheme(WSRS) Yellow River optical properties

Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway

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Chinese Journal of Integrative Medicine 2024年第4期30卷 299-310页

作者： liu xiao-rong li Shuo-fu MEI Wen-ya liu Xiang-dan ZHOU Ri-bao College of Pharmacy Hunan University of Chinese MedicineChangsha(410208)China Department of Orthopaedics The First Hospital of Hunan University of Chinese MedicineChangsha(410007)China

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).Methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(MMP2)or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS function.RA-FLS viability,migration,and invasion were evaluated.Moreover,a collagen-induced arthritis(CIA)rat model was established.Rats were randomly divided to sham,CIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,respectively.Arthritis index was calculated and synovial tissue inflammation was determined in CIA rats.The levels of MMP2,MMP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRC,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(CREB),were detected in RA-FLS and synovial tissue.Molecular docking was also used to analyze the binding of isorhamnetin to SRC.Results In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(Plity,migration and invasion,as well as the negative regulation of MMP2 and MMP9(P<0.05).In in vivo studies,isorhamnetin decreased arthritis index scores(P<0.05)and alleviated synovial inflammation.Isorhamnetin reduced the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRC,ERK,and CREB in synovial tissue(P<0.05).Notably,the inhibit

关键词： rheumatoid arthritis isorhamnetin SRC/ERK/CREB matrix metalloproteinase

Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning

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Advances in Manufacturing 2024年第1期12卷 167-176页

作者： Qiang-Qiang liu Shu-Ting liu Ying-Guang li Xu liu xiao-Zhong Hao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816People’s Republic of China

Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite parts.Traditional embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the part.In this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is proposed.Using the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating patterns.In addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the part.This method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry.

关键词： Online monitoring Curing temperature field Deep learning(DL) In-situ heating

Sliced Average Variance Estimation for Tensor Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 630-655页

作者： Chuan-quan li Pei-wen xiao Chao YING xiao-hui liu School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Biostatistics and Medical Informatics University of Wisconsin MadisonMadison 53726USA

Tensor data have been widely used in many fields,e.g.,modern biomedical imaging,chemometrics,and economics,but often suffer from some common issues as in high dimensional statistics.How to find their low-dimensional latent structure has been of great interest for statisticians.To this end,we develop two efficient tensor sufficient dimension reduction methods based on the sliced average variance estimation(SAVE)to estimate the corresponding dimension reduction subspaces.The first one,entitled tensor sliced average variance estimation(TSAVE),works well when the response is discrete or takes finite values,but is not■consistent for continuous response;the second one,named bias-correction tensor sliced average variance estimation(CTSAVE),is a de-biased version of the TSAVE method.The asymptotic properties of both methods are derived under mild conditions.Simulations and real data examples are also provided to show the superiority of the efficiency of the developed methods.

关键词： tensor data sliced average variance estimation sufficient dimension reduction central subspace

Metabolomic Analysis in Saliva and Different Brain Regions of Older Mice with Postoperative Delirium Behaviors

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Biomedical and Environmental Sciences 2024年第2期37卷 133-145页

作者： liu xiao CAO Ying liN xiao Wan GAO Dan Yang MIAO Hui Hui li Tian Zuo Department of Anesthesiology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

Objective Postoperative delirium(POD)has become a critical challenge with severe consequences and increased incidences as the global population ages.However,the underlying mechanism is yet unknown.Our study aimed to explore the changes in metabolites in three specific brain regions and saliva of older mice with postoperative delirium behavior and to identify potential non-invasive biomarkers.Methods Eighteen-month-old male C57/BL6 mice were randomly assigned to the anesthesia/surgery or control group.Behavioral tests were conducted 24 h before surgery and 6,9,and 24 h after surgery.Complement C3(C3)and S100 calcium-binding protein B protein(S100beta)levels were measured in the hippocampus,and a metabolomics analysis was performed on saliva,hippocampus,cortex,and amygdala samples.Results In total,43,33,38,and 14 differential metabolites were detected in the saliva,hippocampus,cortex,and amygdala,respectively.“Pyruvate”“alpha-linolenic acid”and“2-oleoyl-1-palmitoy-snglycero-3-phosphocholine”are enriched in one common pathway and may be potential non-invasive biomarkers for POD.Common changes were observed in the three brain regions,with the upregulation of 1-methylhistidine and downregulation of D-glutamine.Conclusion Dysfunctions in energy metabolism,oxidative stress,and neurotransmitter dysregulation are implicated in the development of POD.The identification of changes in the level of salivary metabolite biomarkers could aid in the development of noninvasive diagnostic methods for POD.

关键词： Metabolomic Postoperative delirium(POD) Mechanism Biological marker