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Forest management causes soil carbon loss by reducing particulate organic carbon in Guangxi, Southern China

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Forest Ecosystems 2023年第1期10卷 73-81页

作者： xiaojie li Qiufang Zhang Jiguang Feng Demeng Jiang Biao Zhu Institute of Ecology College of Urban and Environmental SciencesKey Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing100871China

Background: The loss of soil organic carbon(SOC) following conversion of natural forests to managed plantations has been widely reported. However, how different SOC fractions and microbial necromass C(MNC) respond to forest management practices remains unclear.Methods: We sampled 0–10 cm mineral soil from three different management plantations and one protected forest in Guangxi, Southern China, to explore how forest management practices affect SOC through changing mineralassociated C(MAOC) and particulate organic C(POC), as well as fungal and bacterial necromass C.Results: Compared with the protected forest, SOC and POC in the abandoned, mixed and Eucalyptus plantations significantly decreased, but MAOC showed no significant change, indicating that the loss of SOC was mainly from decreased POC under forest management. Forest management also significantly reduced root biomass, soil extractable organic C, MNC, and total microbial biomass(measured by phospholipid fatty acid), but increased fungi-to-bacteria ratio(F:B) and soil peroxidase activity. Moreover, POC was positively correlated with root biomass, total microbial biomass and MNC, and negatively with F:B and peroxidase activity. These results suggested that root input and microbial properties together regulated soil POC dynamics during forest management.Conclusion: Overall, this study indicates that forest management intervention significantly decreases SOC by reducing POC in Guangxi, Southern China, and suggests that forest protection can help to sequester more soil C in forest ecosystems.

关键词： Soil organic carbon Forest management Mineral-associated organic carbon Particulate organic carbon Microbial necromass carbon

Janus heterostructure of cobalt and iron oxide as dual-functional electrocatalysts for overall water splitting

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Nano Research 2023年第2期16卷 2245-2251页

作者： xiaojie li Huike Zhang Xuan li Qi Hu Chen Deng Xingxing Jiang Hengpan Yang Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China

In electrocatalytic water splitting,low-cost dual-functional catalysts can not only reduce costs but also avoid cross-contamination of cathode and anode.However,the orderly aggregation of active sites for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)into a specific catalyst is very challenging.In this study,a Co/Fe_(3)O_(4)Janus heterojunction supported on carbon fiber paper(J-CoFe-CFP)is designed and successfully synthesized.Generally,Co-Fe oxides have preferable OER activity but weak HER activity.However,in J-CoFe-CFP,due to the intense and special electronic interaction of different substances(Co and Fe3O4)in the Janus heterogeneous interface,a huge number of tidy high-quality HER and OER active sites are uniformly distributed on the interface simultaneously,which endows the catalyst with both excellent HER and OER performance.In HER,the overpotential@10 mA·cm^(−2)(ηHER)is only 53.9 mV,and the Tafel slope is 43.7 mV·dec^(−1).In OER,theηis 272 mV,and the Tafel slope is 50.2 mV·dec^(−1),much lower than those of RuO_(2)/CFP.In the J-CoFe-CFP||J-CoFe-CFP two-electrode system,the required voltage is only 1.26 V at the beginning and 1.56 V@10 mA·cm^(−2),much lower than those of RuO_(2)/CFP||20%Pt/C/CFP.This work provides a Janus heterojunction pathway for bifunctional water electrolysis catalysts.

关键词： Janus bifunctional electrocatalytic water splitting CoFe

A hierarchically structured tin-cobalt composite with an enhanced electronic effect for high-performance CO_(2) electroreduction in a wide potential range

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Journal of Energy Chemistry 2023年第1期76卷 462-469,I0012页

作者： Xingxing Jiang Xuan li Yan Kong Chen Deng xiaojie li Qi Hu Hengpan Yang Chuanxin He Institute of Microscale Optoelectronics College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060GuangdongChina

Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materials to obtain satisfactory performance at low-to-moderate overpotentials.Herein,a simple and facile electrospinning technique is utilized to prepare a composite of a bimetallic Sn-Co oxide/carbon matrix with a hollow nanotube structure(Sn Co-HNT).Sn Co-HNT can maintain>90%faradaic efficiencies for C1 products within a wide potential range from-0.6 VRHE to-1.2 VRHE,and a highest 94.1%selectivity towards CO in an H-type cell.Moreover,a 91.2%faradaic efficiency with a 241.3 m A cm^(-2)partial current density for C1 products could be achieved using a flow cell.According to theoretical calculations,the fusing of Sn/Co oxides on the carbon matrix accelerates electron transfer at the atomic level,causing electron deficiency of Sn centers and reversible variation between Co^(2+)and Co^(3+)centers.The synergistic effect of the Sn/Co composition improves the electron affinity of the catalyst surface,which is conducive to the adsorption and stabilization of key intermediates and eventually increases the catalytic activity in CO_(2)electroreduction.This study could provide a new strategy for the construction of oxide-derived catalysts for CO_(2)electroreduction.

关键词： Hierarchic structure Tin-cobalt bimetallic oxide Electronic effect CO_(2)electroreduction Wide potential range

Carcinoma-associated fibroblast-derived lysyl oxidase-rich extracellular vesicles mediate collagen crosslinking and promote epithelial-mesenchymal transition via p-FAK/ p-paxillin/YAP signaling

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International Journal of Oral Science 2023年第3期15卷 422-436页

作者： Xue liu Jiao li Xuesong Yang xiaojie li Jing Kong Dongyuan Qi Fuyin Zhang Bo Sun Yuehua liu Tingjiao liu Department of Oral Pathology Shanghai Stomatological Hospital&School of StomatologyFudan UniversityShanghaiChina Shanghai Key Laboratory of Craniomaxillofacial Development and Diseases Fudan UniversityShanghaiChina Department of Orthodontics Shanghai Stomatological Hospital&School of StomatologyFudan UniversityShanghaiChina School of Stomatology Dalian Medical UniversityDalianChina Department of Biochemistry and Molecular Biology Liaoning Provincial Core Lab of Glycobiology and GlycoengineeringDalian Medical UniversityDalianChina Department of Oral Surgery the First Affiliated Hospital of Dalian Medical UniversityDalianChina Department of Oral Surgery the Second Affiliated Hospital of Dalian Medical UniversityDalianChina

Carcinoma-associated fibroblasts(CAFs)are the main cellular components of the tumor microenvironment and promote cancer progression by modifying the extracellular matrix(ECM).The tumor-associated ECM is characterized by collagen crosslinking catalyzed by lysyl oxidase(LOX).Small extracellular vesicles(sEVs)mediate cell-cell communication.However,the interactions between sEVs and the ECM remain unclear.Here,we demonstrated that sEVs released from oral squamous cell carcinoma(OSCC)-derived CAFs induce collagen crosslinking,thereby promoting epithelial-mesenchymal transition(EMT).CAF sEVs preferably bound to the ECM rather than being taken up by fibroblasts and induced collagen crosslinking,and a LOX inhibitor or blocking antibody suppressed this effect.Active LOX(αLOX),but not the LOX precursor,was enriched in CAF sEVs and interacted with periostin,fibronectin,and bone morphogenetic protein-1 on the surface of sEVs.CAF sEV-associated integrinα2β1 mediated the binding of CAF sEVs to collagen I,and blocking integrinα2β1 inhibited collagen crosslinking by interfering with CAF sEV binding to collagen I.CAF sEV-induced collagen crosslinking promoted the EMT of OSCC through FAK/paxillin/YAP pathway.Taken together,these findings reveal a novel role of CAF sEVs in tumor ECM remodeling,suggesting a critical mechanism for CAF-induced EMT of cancer cells.

关键词： Carcinoma inhibited crosslinking

Bimetallic two-dimensional materials for electrocatalytic oxygen evolution

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Chinese Chemical Letters 2022年第8期33卷 3657-3671页

作者： xiaojie li Qi Hu Hengpan Yang Tao Ma Xiaoyan Chai Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Electrocatalytic oxygen evolution reaction(OER)is one of the important half reactions of electrocatalytic water splitting.However,the slow kinetic process involving four-electron transfer severely limits its reaction efficiency,which in turn limits the overall electrocatalytic hydrolysis efficiency.In order to improve the activity of the electrocatalytic OER,researchers mainly update the catalyst from three aspects,that is,increase the conductivity of the electrocatalyst,and the quantity and quality of active sites.Twodimensional(2 D)engineering can effectively reduce the resistance of the materials and greatly increase the number of electrochemically active sites,while heterometal doping,or the bimetal strategy,can improve the quality of active sites via changing the electronic structure of the material.Thus,the combination of the two can enhance the activity of electrocatalytic OER in all three aspects:conductivity,number and quality of active sites.However,there is currently no review on this topic.Therefore,in this review,we summarize the application of bimetallic 2 D materials in electrocatalytic OER from four aspects:the structure,synthesis strategy,catalytic efficiency,and reaction mechanism.

关键词： Bimetal/bimetallic Two-dimensional/2D Oxygen evolution Electrocatalytic MOF LDH

Performance analysis of two RDSS positioning modes of BeiDou-3 system

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Astrodynamics 2022年第3期6卷 317-327页

作者： Dongxia Wang Rui Guo Nan Xing Zhijun liu Tianqiao Zhang Hui Ren xiaojie li Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Operation Control Department Beijing Satellite Navigation CenterBeijing 100094China Astronomy Department Beijing Normal UniversityBeijing 100875China

The BeiDou-3 global satellite navigation system(BDS-3)provides two radio determination satellite service(RDSS)positioning services for users,i.e.,the traditional RDSS(TRDSS)positioning of the BeiDou-2 regional satellite navigation system,and the comprehensive RDSS(CRDSS)positioning,which integrates the RDSS and radio navigation satellite service.As published studies regarding the RDSS positioning service are few,we analyze and compare the performances of the two RDSS positioning modes.First,we systematically investigate the principles of the TRDSS and CRDSS positioning,and then analyze the evaluation methods in terms of their positioning accuracy,real time,and coverage range.Second,based on the BeiDou RDSS measured data,we evaluate the performances of the TRDSS and CRDSS positioning.Compared with TRDSS positioning,CRDSS positioning exhibits the following:1)A significant increase in positioning accuracy,resulting in error improvement from 8 to 2 m and root mean square improvement from 3.13 to 0.85 m;in other words,the positioning error,constant deviation,and stability improve significantly.2)The real time reduces slightly from 1.1 to 1.8 ns,which is within the acceptable range.3)The coverage range expands from the areas of 62°E-145°E and 5°N-55°N to the areas of 50°E-170°E and 0°N-70°N,respectively.4)CRDSS positioning is not restricted by the constraints of the digital elevation database or the user elevation information and can thus solve the occlusion problem effectively.

关键词： TRDSS positioning CRDSS positioning positioning accuracy real time coverage range

van der Waals type II carbon nitride homojunctions for visible light photocatalytic hydrogen evolution

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Nano Research 2023年第4期16卷 5864-5872页

作者： xiaojie li Panpan Zhang Huayang Zhang Wenjie Tian Yangyang Yang Kunsheng Hu Dechao Chen Qin li Xiaoguang Duan Hongqi Sun Shaobin Wang School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA 5005Australia Department of Chemical Engineering Curtin UniversityGPO Box U1987PerthWA 6845Australia Queensland Micro-and Nanotechnology Centre School of Engineering and Built EnvironmentGriffith UniversityNathanQLD 4111Australia School of Engineering Edith Cowan UniversityJoondalupWA 6027Australia

Photocatalytic hydrogen evolution reaction(PC-HER)provides a solution to energy crisis and environmental pollution.Herein,different graphitic carbon nitride(g-C_(3)N_(4))-based van der Waals(vdW)type II homojunctions have been fabricated and g-C_(3)N_(4)/Kdoped g-C_(3)N_(4)nanosheets have an outstanding PC-HER rate of 1,243μmol·h^(−1)·g^(−1)under visible light,higher than that of bulk g-C_(3)N_(4),doped g-C_(3)N_(4)nanosheets,and mixed nanosheets.The enhanced PC-HER performance can be ascribed to the cooperative effects of the shortened bandgap,enlarged specific surface area,matched type II energy band structure,“face to face”vdW charge interaction,and peculiarly partite positions of the conduction and valence bands in different layers.Besides,the type II junctions were found superior to binary type II junction.This study highlights the synergistic effect of different strategies in improving the PC-HER capacities of g-C_(3)N_(4),especially the application of particular vdW junctions,and provides new insights to the structures and mechanism.

关键词： van der Waals junction type II junction hydrogen evolution carbon nitride photocatalyst

Make U-Net Greater: An Easy-to-Embed Approach to Improve Segmentation Performance Using Hypergraph

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Computer Systems Science & Engineering 2022年第7期42卷 319-333页

作者： Jing Peng Jingfu Yang Chaoyang Xia xiaojie li Yanfen Guo Ying Fu Xinlai Chen Zhe Cui Chengdu Institute of Computer Application University of Chinese Academy of SciencesChengdu610041China School of Computer Science Chengdu University of Information TechnologyChengdu610225China University of Chinese Academy of Sciences Beijing100049China Department of Experimental Rheumatology Nijmegen6525GANetherlands

semantics information while maintaining spatial detail con-texts.Long-range context information plays a crucial role in this scenario.How-ever,the traditional convolution kernel only provides the local and small size of the receptiveﬁeld.To address the problem,we propose a plug-and-play module aggregating both local and global information(aka LGIA module)to capture the high-order relationship between nodes that are far apart.We incorporate both local and global correlations into hypergraph which is able to capture high-order rela-tionships between nodes via the concept of a hyperedge connecting a subset of nodes.The local correlation considers neighborhood nodes that are spatially adja-cent and similar in the same CNN feature maps of magnetic resonance(MR)image;and the global correlation is searched from a batch of CNN feature maps of MR images in feature space.The inﬂuence of these two correlations on seman-tic segmentation is complementary.We validated our LGIA module on various CNN segmentation models with the cardiac MR images dataset.Experimental results demonstrate that our approach outperformed several baseline models.

关键词： Convolutional neural network semantic segmentation hypergraph neural network LGIA module

Perceptual Image Outpainting Assisted by Low-Level Feature Fusion and Multi-Patch Discriminator

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Computers, Materials & Continua 2022年第6期71卷 5021-5037页

作者： xiaojie li Yongpeng Ren Hongping Ren Canghong Shi Xian Zhang Lutao Wang Imran Mumtaz Xi Wu College of Computer Science Chengdu University of Information TechnologyChengdu610225China Xihua University Chengdu610039China University of Agriculture Faisalabad Pakistan

Recently,deep learning-based image outpainting has made greatly notable improvements in computer vision field.However,due to the lack of fully extracting image information,the existing methods often generate unnatural and blurry outpainting results in most cases.To solve this issue,we propose a perceptual image outpainting method,which effectively takes the advantage of low-level feature fusion and multi-patch discriminator.Specifically,we first fuse the texture information in the low-level feature map of encoder,and simultaneously incorporate these aggregated features reusability with semantic(or structural)information of deep feature map such that we could utilizemore sophisticated texture information to generate more authentic outpainting images.Then we also introduce a multi-patch discriminator to enhance the generated texture,which effectively judges the generated image from the different level features and concurrently impels our network to produce more natural and clearer outpainting results.Moreover,we further introduce perceptual loss and style loss to effectively improve the texture and style of outpainting images.Compared with the existing methods,our method could produce finer outpainting results.Experimental results on Places2 and Paris StreetView datasets illustrated the effectiveness of our method for image outpainting.

关键词： Deep learning image outpainting low-level feature fusion multi-patch discriminator