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Human disturbance exacerbated erosion and deposition in the karst peak-cluster depressions during the Ming and Qing dynasties

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Science China Earth Sciences 2024年第11期67卷 3550-3561页

作者： Shuai YUAN Yuemin YUE Xinbao ZHANG lu WANG lu ZHAI Kelin WANG Key Laboratory for Agro-Ecological Processes in Subtropical Region Institute of Subtropical Agriculture Chinese Academy of Sciences Huanjiang Observation and Research Station for Karst Ecosystems Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Mountain Hazards and Environment Ministry of Water Resources Chinese Academy of Sciences State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences

Under the background of large-scale ecological restoration, China's southwestern karst region has become a hotspot of global vegetation cover “greening” in the past 20 years. However, because of geological constraints, it is difficult to restore the forest landscapes in some areas. It is urgent to understand the impacts of human disturbances during the historical period on the difficult-to-forestation rocky-desertification areas of the karst region in order to guide future afforestation. In this study, we quantified the changes of specific sediment yield in typical karst depressions over the past 500 years by using137Cs,210Pb, and14C dating methods in karst depressions, and identified the main human disturbances related to historical erosion and sedimentation by combining with historical data. The results showed that the erosion and sedimentation of the three depressions in 1921–1963 were significantly higher than that in 1963–2021, and the sedimentation rate(0.64–1.33 cm a-1) and the specific sediment yield(2.51–13.11 t ha-1a-1) during Ming and Qing dynasties（1504–1812） were higher than the sedimentation rate(0.26–0.95 cm a-1) and specific sediment yield(0.95–6.99 t ha-1a-1) in the recent century（1921–2021）. Reconstruction data and literature from the Ming and Qing dynasties show an empirical link between changes in population, arable land, food, forest area,and deforestation events during the same period. It was found that the population and arable land in Guangxi increased more than three-fold and the forest area decreased significantly in the 17th century after the migration of the Yao ethnic group and the introduction of maize to the region, which may be the main reason for intensifying the erosion of depressions. This study is of great significance to understanding the evolution history of rocky desertification in this region and to answer the potential of afforestation.

关键词： Karst region 14C dating Peak-cluster depressions Ethnic minirity migration Specific sediment yield

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Effectiveness of magnetic resonance imaging and spiral computed tomography in the staging and treatment prognosis of colorectal cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2135-2144页

作者： lu-Na Bai lu-Xian Zhang Department of Radiology Zhongshan Hospital Xiamen UniversityXiamen 361004Fujian ProvinceChina

BACKGROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many *** early detection and diagnosis of CRC are crucial for improving treatment success and patient survival ***,imaging techniques have been hypothesized to be essential in managing CRC,with magnetic resonance imaging(MRI)and spiral computed tomography(SCT)playing a significant role in enhancing diagnostic and treatment *** To explore the effectiveness of MRI and SCT in the preoperative staging of CRC and the prognosis of laparoscopic *** Ninety-five individuals admitted to Zhongshan Hospital Xiamen University underwent MRI and SCT and were diagnosed with *** precision of MRI and SCT for the presurgical classification of CRC was assessed,and pathological staging was used as a *** operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume,blood flow,time to peak,permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction on the prognosis of patients with *** Pathological biopsies confirmed the following CRC stages:23,23,32,and 17 at T1,T2,T3,and T4,*** were 39 cases at the N0 stage,22 at N1,34 at N2,44 at M0 stage,and 51 at *** pathological findings as the benchmark,the combined use of MRI and SCT for preoperative TNM staging in patients with CRC demonstrated superior sensitivity,specificity,and accuracy compared with either modality alone,with a statistically significant difference in accuracy(Plues for laparoscopic treatment prognosis,as indicated by the areas under the curve for blood volume,blood flow,time to peak,and permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volu

关键词： Magnetic resonance imaging Spiral computed tomography Colorectal cancer Prognosis Receiver operating characteristic curve Retrospective study

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Construction management and technical innovation of the Beijing–Shanghai High Speed Railway

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Frontiers of Engineering Management 2024年第3期11卷 584-587页

作者： Chunfang lu Chinese Academy of Engineering Beijing 100088China

1 Project overview The Beijing–Shanghai High Speed Railway(HSR)represents a major national strategic transportation project in China that is characterized by the largest-scale one-time investment in the *** the time,it was the longest HSR constructed in a single phase,with the highest technical standards in the *** as an HSR artery between the Northern and Eastern regions of China,the Beijing–Shanghai HSR is the busiest HSR with the highest ridership in the country and the world at ***,it is the only commercial HSR consistently operates at a speed of 350 km/h globally.

关键词： Beijing–Shanghai High Speed Railway project construction project management technological innovation

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Achieving a superior Na storage performance of Fe-based Prussian blue cathode by coating perylene tetracarboxylic dianhydride amine

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Carbon Energy 2024年第5期6卷 53-64页

作者： Xin-Yuan Fu lu-lu Zhang Zhao-Yao Chen Yunkai Xu Junxiu Wu Cheng-Cheng Wang Xiao-Kai Ding Xue-Lin Yang Jun lu Hubei Provincial Collaborative Innovation Center for New Energy Microgrid College of Electrical Engineering&New EnergyChina Three Gorges UniversityYichangHubeiChina College of Materials and Chemical Engineering China Three Gorges UniversityYichangHubeiChina College of Chemical and Biological Engineering Zhejiang UniversityHangzhouChina

Fe-based Prussian blue(Fe-PB)cathode material shows great application potential in sodium(Na)-ion batteries due to its high theoretical capacity,long cycle life,low cost,and simple preparation ***,the crystalline water and vacancies of Fe-PB lattice,the low electrical conductivity,and the dissolution of metal ions lead to limited capacity and poor cycling *** this work,a perylene tetracarboxylic dianhydride amine(PTCDA)coating layer is successfully fabricated on the surface of Fe-PB by a liquid-phase *** aminated PTCDA(PTCA)coating not only increases the specific surface area and electronic conductivity but also effectively reduces the crystalline water and vacancies,which avoids the erosion of Fe-PB by ***,the PTCA layer reduces the charge transfer resistance,enhances the Na-ion diffusion coefficient,and improves the structure *** PTCA-coated Fe-PB exhibits superior Na storage performance with a first discharge capacity of 145.2 mAh g^(−1) at 100 mA g^(−1).Long cycling tests exhibit minimal capacity decay of 0.027%per cycle over 1000 cycles at 1 A g^(−1).Therefore,this PTCA coating strategy has shown promising competence in enhancing the electrochemical performance of Fe-PB,which can potentially serve as a universal electrode coating strategy for Na-ion batteries.

关键词： cathode material coating Fe-based Prussian blue Na-ion batteries perylene tetracarboxylic dianhydride amine

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Upconversion-based chiral nanoprobe for highly selective dual-mode sensing and bioimaging of hydrogen sulfide in vitro and in vivo

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Light(Science & Applications) 2024年第9期13卷 1878-1887页

作者： Yang lu Xu Zhao Dongmei Yan Yingqian Mi Peng Sun Xu Yan Xiaomin Liu Geyu lu State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University130012 ChangchunChina Department of Immunology College of Basic Medical SciencesJilin University130021 ChangchunChina

Chiral assemblies have become one of the most active research areas due to their versatility,playing an increasingly important role in bio-detection,imaging and *** this work,chiral UCNPs/CuxOS@ZIF nanoprobes are prepared by encapsulating upconversion nanoparticles(UCNPs)and CuxOS nanoparticles(NPs)into zeolitic imidazolate framework-8(ZIF-8).The novel excited-state energy distribution-modulated upconversion nanostructure(NaYbF4@-NaYF4:Yb,Er)is selected as the fluorescence source and energy donor for highly efficient fluorescence resonance energy transfer(FRET).CuxOS NP is employed as chiral source and energy acceptor to quench upconversion luminescence(UCL)and provide circular dichroism(CD)*** the natural adsorption and sorting advantages of ZIF-8,the designed nanoprobe can isolate the influence of other common disruptors,thus achieve ultra-sensitive and highly selective UCL/CD dual-mode quantification of H2S in aqueous solution and in living ***,the nanoprobe is also capable of in vivo intra-tumoral H2S *** work highlights the multifunctional properties of chiral nanocomposites in sensing and opens a new vision and idea for the preparation and application of chiral nanomaterials in biomedical and biological analysis.

关键词： chiral sulfide donor

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Recent Advances in Biomass-derived Porous Carbon Materials:Synthesis,Composition and Applications

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Chemical Research in Chinese Universities 2024年第1期40卷 3-19页

作者： ZHAI Ziqi lu Yumiao LIU Guangyong DING Wei-lu CAO Bobo HE Hongyan CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Mesoscience and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Longzihu New Energy Laboratory Zhengzhou Institute of Emerging Industrial TechnologyZhengzhou 450000P.R.China

Porous carbon materials(PCMs)play a pivotal role in diverse applications,such as energy storage,adsorption,catalysis,environmental remediation,and microwave *** selection of carbon precursors,in particular,is crucial for tailoring porous structures with specific ***,with its rich carbon feedstock,abundant availability,renewability,and versatile structures,has emerged as a promising precursor for porous carbon material *** review comprehensively summarizes the recent advances in biomass-derived porous carbon materials(BPCMs)encompassing synthetic strategy,morphology,structural composition,and multiple *** first review synthetic approaches aiming at regulating porosity,followed by morphological and composition features of BPCMs,with a special emphasis on elucidating the dimensional clarification and heteroatom doping *** discussion then extends to the wide-ranging applications of BPCMs,covering energy-related applications and CO_(2) adsorption to environmental ***,the review outlines the existing challenges and prospects in the *** summary,this review systematically describes BPCMs and provides valuable guidance for researchers to select and synthesize BPCMs that meet specific functional requirements.

关键词： Biomass Porous carbon Pyrolysis Heteroatom-doping Supercapacitor CO_(2)adsorption

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Well-dispersed Sb particles embedded on N-doped carbon nanofibers toward high-performance Li-ion battery

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Rare Metals 2024年第7期43卷 2994-3006页

作者： Ying Li Yi-Han Zhao lu-lu Zhao Peng-Fei Wang Ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004China Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

The alloy-type material Sb is widely used in the anode materials of lithium-ion batteries(LIBs)due to its high theoretical specific ***,its serious volume expansion problem during alloying/dealloying of Li~+limits its practical *** this work,C-Sb composite was constructed as anode material of LIBs by electrospinning route for the first time,Sb was introduced into the polyacrylonitrile-based hard carbon and coal tar pitch-based soft carbon composite amorphous carbon fiber with a diameter of 300-600 nm,which realized high cycling *** C-Sb-2(the mass ratio of polyacrylonitrile to Sb source is 1:2)electrode displayed charge capacities of 1098.5,930.3,841.7,753.5,643.9 and 545.8 mAh·g^(-1)at 0.1,0.2,0.3,0.5,1 and 2 A·g^(-1),*** when the current density returned to 0.1 A·g^(-1),the charge capacity was 939.3 mAh·g^(-1),revealing good stability and *** introduction of Sb into the amorphous carbon improved its conductivity and addressed the volume expansion issue of high specific capacity Sb during charge/***-situ XRD analysis confirmed the high reversibility of the C-Sb-2 during charging and *** functional theory(DFT)calculations revealed the gradual enhancement of the interface interaction between Sb_(x)Li_(y) and amorphous carbon(AMC)with increasing lithium content,contributing to the anchoring of alloy nanoparticles on the AMC surface and buffering the volume change of the ***,the gradual lithiation of Sb facilitated the electron transfer from Sb_(x)Li_(y) to *** findings hold promise for designing lithium storage materials with exceptional performance,highlighting the potential of C-Sb composites as anode materials for efficient next-generation lithium storage.

关键词： Li-ion battery Metallic Sb Carbon Electrospinning Cycling stability

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A Degree Condition for Graphs Having All(a,b)-parity Factors

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 656-664页

作者： Hao-dong LIU Hong-liang lu School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China

Let a and b be positive integers such that a≤b and a≡b(mod 2).We say that G has all(a,b)-parity factors if G has an h-factor for every function h:V(G)→{a,a+2,…,b-2,b} with b|V(G)| even and h(v)≡b(mod 2) for all v∈V(G).In this paper,we prove that every graph G with n≥2(b+1)(a+b) vertices has all(a,b)-parity factors if δ(G)≥(b^(2)-b)/a,and for any two nonadjacent vertices u,v ∈V(G),max{d_(G)(u),d_(G)(v)}≥bn/a+***,we show that this result is best possible in some sense.

关键词： degree condition all(a,b)-factors

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Online distributed optimization with stochastic gradients:high probability bound of regrets

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Control Theory and Technology 2024年第3期22卷 419-430页

作者： Yuchen Yang Kaihong lu Long Wang Center for Systems and Control College of EngineeringPeking UniversityBeijing 100871China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590ShandongChina

In this paper,the problem of online distributed optimization subject to a convex set is studied via a network of *** agent only has access to a noisy gradient of its own objective function,and can communicate with its neighbors via a *** handle this problem,an online distributed stochastic mirror descent algorithm is *** works on online distributed algorithms involving stochastic gradients only provide the expectation bounds of the *** from them,we study the high probability bound of the regrets,i.e.,the sublinear bound of the regret is characterized by the natural logarithm of the failure probability's *** mild assumptions on the graph connectivity,we prove that the dynamic regret grows sublinearly with a high probability if the deviation in the minimizer sequence is sublinear with the square root of the time ***,a simulation is provided to demonstrate the effectiveness of our theoretical results.

关键词： Distributed optimization Online optimization Stochastic gradient High probability

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Neuropeptide Y receptor Y8b(npy8br)regulates feeding and digestion in Japanese medaka(Oryzias latipes)larvae:evidence from gene knockout

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第7期25卷 605-616页

作者： Xiaodan JIA Ke lu Xufang LIANG College of Fisheries Chinese Perch Research CenterHuazhong Agricultural UniversityWuhan 430070China Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt Ministry of EducationWuhan 430070China

Neuropeptide Y receptor Y8(NPY8R)is a fish-specific receptor with two subtypes,NPY8AR and *** in expression levels during physiological processes or in vivo regulation after ventricular injection suggest that NPY8BR plays an important role in feeding regulation;this has been found in only a few fish,at *** order to better understand the physiological function of npy8br,especially in digestion,we used clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)technology to generate npy8br-/-japanese medaka(Oryzias latipes).We found that the deletion of npy8br in medaka larvae affected their feeding and digestion ability,ultimately affecting their ***,npy8br deficiency in medaka larvae resulted in decreased feed intake and decreased expression levels of orexigenic genes(npy and agrp).npy8br-/-medaka larvae fed for 10 d(10th day of feeding)still had incompletely digested brine shrimp(Artemia nauplii)in the digestive tract 8 h after feeding,the messenger RNA(mRNA)expression levels of digestion-related genes(amy,lpl,ctra,and ctrb)were significantly decreased,and the activity of amylase,trypsin,and lipase also significantly *** deletion of npy8br in medaka larvae inhibited the growth and significantly decreased the expression of growth-related genes(gh and igf1).Hematoxylin and eosin(H&E)sections of intestinal tissue showed that npy8br-/-medaka larvae had damaged intestine,thinned intestinal wall,and shortened intestinal *** far,this is the first npy8br gene knockout model established in fish and the first demonstration that npy8br plays an important role in digestion.

关键词： Neuropeptide Y receptor Y8b(npy8br) Japanese medaka(Oryzias latipes) Knockout Feeding Digestion

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