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Improving model performance in mapping cropland soil organic matter using time-series remote sensing data

Journal of Integrative Agriculture 2024年第8期23卷 2820-2841页

作者： Xianglin Zhang Jie Xue Songchao chen Zhiqing Zhuo Zheng Wang Xueyao chen yi Xiao Zhou Shi Institute of Applied Remote Sensing and Information Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Department of Land Management Zhejiang UniversityHangzhou 310058China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Institute of Digital Agriculture Zhejiang Academy of Agricultural SciencesHangzhou 310021China Key Laboratory of Spectroscopy Sensing Ministry of Agriculture and Rural AffairsHangzhou 310058China

Faced with increasing global soil degradation,spatially explicit data on cropland soil organic matter(SOM)provides crucial data for soil carbon pool accounting,cropland quality assessment and the formulation of effective management *** a spatial information prediction technique,digital soil mapping(DSM)has been widely used to spatially map soil information at different ***,the accuracy of digital SOM maps for cropland is typically lower than for other land cover types due to the inherent difficulty in precisely quantifying human *** overcome this limitation,this study systematically assessed a framework of“information extractionfeature selection-model averaging”for improving model performance in mapping cropland SOM using 462 cropland soil samples collected in Guangzhou,China in *** results showed that using the framework of dynamic information extraction,feature selection and model averaging could efficiently improve the accuracy of the final predictions(R^(2):0.48 to 0.53)without having obviously negative impacts on *** the dynamic information of the environment was an efficient way to generate covariates that are linearly and nonlinearly related to SOM,which improved the R^(2)of random forest from 0.44 to 0.48 and the R^(2)of extreme gradient boosting from 0.37to *** recursive feature selection(FRFS)is recommended when there are relatively few environmental covariates(500).The Granger-Ramanathan model averaging approach could improve the prediction accuracy and average *** the structures of initial prediction models are similar,increasing in the number of averaging models did not have significantly positive effects on the final *** the advantages of these selected strategies over information extraction,feature selection and model averaging have a great potential for high-accuracy soil mapping

关键词： cropland soil organic matter digital soil mapping machine learning feature selection model averaging

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Geometric phase-encoded stimuli-responsive cholesteric liquid crystals for visualizing real-time remote monitoring:humidity sensing as a proof of concept

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Light(Science & Applications) 2024年第2期13卷 283-293页

作者： Shi-Long Li Zhao-yi chen Peng chen Wei Hu Chaohong Huang Sen-Sen Li Xuejia Hu Yan-Qing Lu Lu-Jian chen Department of Electronic Engineering School of Electronic Science and EngineeringXiamen University361005 XiamenChina College of Engineering and Applied Sciences Nanjing University210093 NanjingChina Fujian Key Laboratory of Ultrafast Laser Technology and Applications Xiamen University361005 XiamenChina

Liquid crystals are a vital component of modern photonics,and recent studies have demonstrated the exceptional sensing properties of stimuli-responsive cholesteric liquid ***,existing cholesteric liquid crystal-based sensors often rely on the naked eye perceptibility of structural color or the measurement of wavelength changes by spectrometric tools,which limits their practical ***,developing a platform that produces recognizable sensing signals is *** this study,we present a visual sensing platform based on geometric phase encoding of stimuli-responsive cholesteric liquid crystal polymers that generates real-time visual patterns,rather than frequency *** demonstrate this platform’s effectiveness,we used a humidity-responsive cholesteric liquid crystal polymer film encoded with a q-plate pattern,which revealed that humidity causes a shape change in the vortex beam reflected from the encoded cholesteric liquid crystal ***,we developed a prototype platform towards remote humidity monitoring benefiting from the high directionality and long-range transmission properties of laser beams carrying orbital angular *** approach provides a novel sensing platform for cholesteric liquid crystals-based sensors that offers promising practical *** ability to generate recognizable sensing signals through visual patterns offers a new level of practicality in the sensing field with stimuli-responsive cholesteric liquid *** platform might have significant implications for a broad readership and will be of interest to researchers working in the field of photonics and sensing technology.

关键词： humidity visual liquid

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Electro-reductive carboxylation of acyclic C(sp^(3))–C(sp^(3))bonds in aromatic hydrocarbons with CO_(2)

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Science China Chemistry 2024年第10期67卷 3366-3372页

作者： Chuan-Kun Ran Quan Qu Yang-yi Tao yi-Fei chen Li-Li Liao Jian-Heng Ye Da-Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China West China School of Public Health and West China Fourth Hospital Sichuan UniversityChengdu 610064China

Despite the recent advances in the selective functionalization of C–C bonds in specific substrates,cleavage and functionalization of C–C bonds in acyclic substrates,such as ethane derivatives,remains *** contrast to the well-developed functionalization of one carbon fragment after C–C bond cleavage,herein,we report a novel electro-reductive carboxylation of C(sp^(3))–C(sp^(3))bond in multi-aryl ethanes with carbon dioxide(CO_(2))by utilizing both carbon ***,this reaction exhibits an atom-,step-economic approach for the synthesis of carboxylic acids,fulfilling principal aspirations of organic ***,this method features mild reaction conditions,broad substrate scope,and good functional group *** and asymmetric substrates bearing primary,secondary,or tertiary C(sp^(3))–C(sp^(3))bonds are all amenable to this strategy,enabling one or two structurally different carboxylic acids to be facilely constructed at the same *** investigations indicate that carbanions might be the key intermediates in this reaction,which could be captured by CO_(2)efficiently.

关键词： carbon dioxide electrochemistry C(sp^(3))–C(sp^(3))bonds cleavage reductive carboxylation

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Ultrahigh thermoelectric properties of p‐type Bi_(x)Sb_(2−x)Te_(3)thin films with exceptional flexibility for wearable energy harvesting

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Carbon Energy 2024年第8期6卷 273-284页

作者： Zhuang‐Hao Zheng yi‐Ming Zhong yi‐Liu Li Mohammad Nisar Adil Mansoor Fu Li Shuo chen Guang‐Xing Liang Ping Fan Dongyan Xu Meng Wei Yue‐Xing chen Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina Department of Mechanical and Automation Engineering The Chinese University of Hong KongSha TinChina

Use of a flexible thermoelectric source is a feasible approach to realizing selfpowered wearable electronics and the Internet of *** thin films are promising candidates for fabricating flexible power supply,but obtaining highthermoelectric‐performance thin films remains a big *** the present work,a p‐type Bi_(x)Sb_(2−x)Te_(3)thin film is designed with a high figure of merit of 1.11 at 393 K and exceptional flexibility(less than 5%increase in resistance after 1000 cycles of bending at a radius of∼5 mm).The favorable comprehensive performance of the Bi_(x)Sb_(2−x)Te_(3)flexible thin film is due to its excellent crystallinity,optimized carrier concentration,and low elastic modulus,which have been verified by experiments and theoretical ***,a flexible device is fabricated using the prepared p‐type Bi_(x)Sb_(2−x)Te_(3)and n‐type Ag_(2)Se thin ***,an outstanding power density of∼1028μWcm^(−2)is achieved at a temperature difference of 25 *** work extends a novel concept to the fabrication of highperformance flexible thin films and devices for wearable energy harvesting.

关键词： Bi_(x)Sb_(2−x)Te_(3) electrical transport properties flexibility thermoelectric

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A Post-Quantum Cross-Domain Authentication Scheme Based on Multi-Chain Architecture

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Computers, Materials & Continua 2024年第2期78卷 2813-2827页

作者： yi-Bo Cao Xiu-Bo chen Yun-Feng He Lu-Xi Liu yin-Mei Che Xiao Wang Ke Xiao Gang Xu Si-yi chen Information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China Information Center of China North Industries Group Corporation Beijing100089China School of Information Science and Technology North China University of TechnologyBeijing100144China

Due to the rapid advancements in network technology,blockchain is being employed for distributed data *** the Internet of Things(IoT)scenario,different participants manage multiple blockchains located in different trust domains,which has resulted in the extensive development of cross-domain authentication ***,the emergence of many attackers equipped with quantum computers has the potential to launch quantum computing attacks against cross-domain authentication schemes based on traditional cryptography,posing a significant security *** response to the aforementioned challenges,our paper demonstrates a post-quantum cross-domain identity authentication scheme to negotiate the session key used in the cross-chain asset exchange ***,our paper designs the hiding and recovery process of user identity index based on lattice cryptography and introduces the identity-based signature from lattice to construct a post-quantum cross-domain authentication ***,our paper utilizes the hashed time-locked contract to achieves the cross-chain asset exchange of blockchain nodes in different trust ***,the security analysis reduces the security of the identity index and signature to Learning With Errors(LWE)and Short Integer Solution(SIS)assumption,respectively,indicating that our scheme has post-quantum *** but not least,through comparison analysis,we display that our scheme is efficient compared with the cross-domain authentication scheme based on traditional cryptography.

关键词： Cross-domain identity authentication lattice-based cryptography blockchain hashed time-locked contract

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Impact of Air Pollutants on Lung Function and Inflammatory Response in Asthma in Shanghai

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Biomedical and Environmental Sciences 2024年第8期37卷 811-822页

作者： Guifang Wang Youzhi Zhang Haiyan Yang yi Yang Liang Dong Peng Zhang Jie Liu Xiaodong chen yi Gong Department of Respiratory and Critical Care Medicine Quzhou People's HospitalQuzhou 324000ZhejiangChina Department of Respiratory and Critical Care Medicine Huashan Hospital Affiliated to Fudan UniversityShanghai 200040China Centre of Hydrogen Science Shanghai Jiao Tong University&Key Lab of Hydrogen ScienceShanghai 200240China Department of Respiratory and Critical Care Medicine Shanghai Public Health Clinical CentreFudan UniversityShanghai 201508China

Objective Air pollution is a leading public health *** study investigated the effect of air quality and pollutants on pulmonary function and inflammation in patients with asthma in *** The study monitored 27 asthma outpatients for a year,collecting data on weather,patient self-management[daily asthma diary,peak expiratory flow(PEF)monitoring,medication usage],spirometry and serum *** explore the potential mechanisms of any effects,asthmatic mice induced by ovalbumin(OVA)were exposed to PM_(2.5).Results Statistical and correlational analyses revealed that air pollutants have both acute and chronic effects on *** exposure showed a correlation between PEF and levels of ozone(O_(3))and nitrogen dioxide(NO_(2)).Chronic exposure indicated that interleukin-5(IL-5)and interleukin-13(IL-13)levels correlated with PM_(2.5)and PM_(10)*** asthmatic mouse models,exposure to PM_(2.5)increased cytokine levels and worsened lung ***,PM_(2.5)exposure inhibited cell proliferation by blocking the NF-κB and ERK phosphorylation *** Ambient air pollutants exacerbate asthma by worsening lung function and enhancing Th2-mediated ***,PM_(2.5)significantly contributes to these adverse *** research is needed to elucidate the mechanisms by which PM_(2.5)impacts asthma.

关键词： Ambient air pollutants Acute and chronic effects on asthma PM_(2.5) OVA-induced asthmatic mice

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Functional Changes in Astrocytes Lead to Cognitive Deficits After Social Deprivation

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Neuroscience Bulletin 2024年第4期40卷 547-549页

作者： Yulan Li Lixuan Li yibei Wang yi Wang Zhong chen Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhou310053China Department of Neurology Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou310009ZhejiangChina

Social experience has a far-reaching impact on the brain and *** humans,lacking social experience during childhood is associated with a faster decline in later-life cognitive function[l],while social isolation in the elderly is an independent risk factor for dementia[2].The lack of social experience at different stages of life has significant adverse effects on cognitive development and mental *** have largely been focused on the neuronal activity and synaptic plasticity changes after social *** recent studies separately reported increased expression of an astrocyte marker,glial fibrillary acidic protein,in socially isolated perinatal or adult mice demonstrating structural changes in astrocytes after social deprivation[3,4].However,it is still unknown whether and how astrocyte function is impacted by social deprivation.

关键词： faster function Functional

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Reveal more mechanisms of precondition mesenchymal stem cells inhibiting inflammation

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World Journal of Stem Cells 2024年第4期16卷 459-461页

作者： yi Li Qian-Qian chen En-Qiang Linghu Department of Gastroenterology First Medical Center of Chinese PLA General HospitalBeijing 100853China Department of Gastroenterology and Hepatology First Medical Center of Chinese PLA General HospitalBeijing 100853China

Hypoxia can get more ability to inhibit *** how it impact on survival time of mesenchymal stem cells(MSCs)is confusing and how preconditioned MSCs inhibiting inflammation are partially *** issues decided the value of ... 详细信息

关键词： Mesenchymal stem cell Hypoxia-inducible factor 1α Hypoxia Inflammation Macrophage

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Effect of dry-wet cycles on dynamic properties and microstructures of sandstone:Experiments and modelling

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International Journal of Mining Science and Technology 2024年第5期34卷 655-679页

作者： Hai Pu Qingyu yi Andrey P.Jivkov Zhengfu Bian Weiqiang chen Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Earth Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China Department of Solids and Structures School of EngineeringUniversity of ManchesterManchester M139PLUK School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Department of Civil and Environmental Engineering Rice UniversityHouston 77005USA State Key Laboratory of High Performance Civil Engineering Materials Jiangsu Research Institute of Building Science Co.Ltd.Nanjing 210008China Department of Materials University of OxfordOxford OX13PHUK

Underground pumped storage power plant(UPSP)is an innovative concept for space recycling of abandoned *** realization requires better understanding of the dynamic performance and durability of reservoir *** paper conducted ultrasonic detection,split Hopkinson pressure bar(SHPB)impact,mercury intrusion porosimetry(MIP),and backscatter electron observation(BSE)tests to investigate the dynamical behaviour and microstructure of sandstone with cyclical dry-wet damage.A coupling FEM-DEM model was constructed for reappearing mesoscopic structure *** results show that dry-wet cycles decrease the dynamic compressive strength(DCS)with a maximum reduction of 39.40%,the elastic limit strength is reduced from 41.75 to 25.62 *** sieved fragments obtain the highest crack growth rate during the 23rd dry-wet cycle with a predictable life of 25 cycles for each rock *** pore fractal features of the macropores and micro-meso pores show great differences between the early and late cycles,which verifies the computational statistics analysis of particle *** numerical results show that the failure patterns are governed by the strain in pre-peak stage and the shear cracks are *** dry-wet cycles reduce the energy transfer efficiency and lead to the discretization of force chain and crack fields.

关键词： Underground pumped storage power plant Dry-wet cycles Split Hopkinson pressure bar Macro and micro properties FEM-DEM coupling model Damage characterization

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Enhancement of low-temperature toughness of Fe-Mn-C-Al alloy by rare earth Ce-modified inclusions

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Journal of Iron and Steel Research International 2024年第1期31卷 157-173页

作者： Guang-kai Yang Chang-ling Zhuang yi-zhuang Li chen Hu Shao-bo Li College of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina Department of Mechanical Engineering University of Hong KongHong Kong999077China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025GuizhouChina

Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and ***,their limited low-temperature toughness restricts their large-scale applications in specific *** influence of trace amounts of rare earth cerium(Ce)on the low-temperature toughness of Fe-18Mn-0.6C-1.8Al alloys was *** addition of Ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth *** leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic *** presence of Ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption ***-cally,the addition of rare earth Ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure *** impact toughness of the Fe-Mn-C-Al alloy is significantly improved by the addition of 0.0048 wt.%Ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.

关键词： Fe-Mn-C-Al alloy Rare earth Low-temperature toughness Inclusion Fracture

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