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Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

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Journal of Forestry Research 2024年第3期35卷 111-130页

作者： xin Chen yujun sun State Forestry&Grassland Administration Key Laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong Qin xin-yu Wang Qaiser Mahmood Zhi-xin yu Yi-Zhou Wang Song Zou Tong-Ling Liang Wen-Hua sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

Constructing S-scheme charge separation in cobalt phthalocyanine/oxygen-doped g-C_(3)N_(4) heterojunction with enhanced photothermal-assisted photocatalytic H_(2) evolution

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Rare Metals 2024年第1期43卷 198-211页

作者： Wei-Long Shi Zheng Xu yu-xing Shi Ling-Ling Li Jia-Lin Lu xin-Hai sun xin Du Feng Guo Chang-yu Lu School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina College of Chemistry Zhengzhou UniversityZhengzhou 450001China School of Water Resource and Environment Hebei Province Key Laboratory of Sustained Utilization and Development of Water RecourseHebei Center for Ecological and Environmental Geology ResearchHebei Geo UniversityShijiazhuang 050031China

Hydrogen acquisition from solar energy is an effective way to address energy crisis,which makes the development of efficient photocatalysts become the main direction of scientific ***,cobalt phthalocyanine/oxygen-doped g-C_(3)N_(4)(CoPc/OCN) S-scheme heterojunction photocatalyst was designed by coupling multi-step calcination with solvothermal method for enhanced photothermal-assisted photocatalytic H_(2) *** multistep calcined g-C_(3)N_(4) is easier for O-doping formation,and the ethanol solvothermal strategy is utilized to enhance the dispersion of CoPc on OCN nano sheet surface and forms sufficient S-scheme heterojunction through *** addition,the active sites and excellent photothermal properties of CoPc itself further improve the integrated photocatalytic activity of CoPc/OCN S-scheme *** optimal photocatalytic hydrogen evolution rate of CoPc/OCN S-scheme heterojunction photocatalyst reached 9.56 mmol·g^(-1)·h^(-1),which is 2.69 and 1.23 times higher than that of CN and OCN,*** work provides a valuable design idea and scheme for enhancing the multi-factor co-assisted photocatalytic H_(2) evolution performance.

关键词： Photothermal Photocatalytic H_(2)evolution Cobalt phthalocyanine Oxygen-doped g-C_(3)N_(4) Sscheme heterojunction

cis-Clerodane Diterpenoids with Structural Diversity and Anti-inflammatory Activity from Tinospora crispa

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Chinese Journal of Chemistry 2022年第24期40卷 2882-2892,I0002页

作者： Jin-Qiu You Yi-Nan Liu Jun-Su Zhou xin-yu sun Chun Lei Qing Mu Jing-Ya Li Ai-Jun Hou School of Pharmacy Fudan UniversityShanghai201203 China School of Pharmacy Shanghai Jiao Tong UniversityShanghai200240 China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai201203 China

Twelve new cis-clerodane diterpenoids, designated as crispinoids A—L (1—12), together with three known analogues (13—15), were isolated from Tinospora crispa. Their structures were fully assigned by comprehensive spectroscopic techniques, single-crystal X-ray diffraction experiments, and electronic circular dichroism (ECD) analyses. The isolated clerodanes displayed diverse heterocyclic frameworks including 6/6/6-, 6/5/6/6-, 6/6/5-, 6/6-, and 6/5/6-fused ring systems. Some of the isolates showed ATP-citrate lyase (ACLY) and nuclear factor kappa B (NF-κB) pathway inhibition. The NF-κB inhibitors further suppressed the lipopolysaccharide (LPS)-induced inflammatory responses in RAW 264.7 cells.

关键词： Natural products Structure elucidation Tinospora crispa ATP-citrate lyase Nuclear factor kappa B

Learning to represent 2D human face with mathematical model

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 54-68页

作者： Liping Zhang Weijun Li Linjun sun Lina yu xin Ning Xiaoli Dong AnnLab Institute of SemiconductorsChinese Academy of SciencesBeijingChina Center of Materials Science and Optoelectronics Engineering School of Integrated CircuitsUniversity of Chinese Academy of SciencesBeijingChina Beijing Key Laboratory of Semiconductor Neural Network Intelligent Sensing and Computing Technology BeijingChina

How to represent a human face pattern?While it is presented in a continuous way in human visual system,computers often store and process it in a discrete manner with 2D arrays of *** authors attempt to learn a continuous surface representation for face image with explicit ***,an explicit model(EmFace)for human face representation is pro-posed in the form of a finite sum of mathematical terms,where each term is an analytic function ***,to estimate the unknown parameters of EmFace,a novel neural network,EmNet,is designed with an encoder-decoder structure and trained from massive face images,where the encoder is defined by a deep convolutional neural network and the decoder is an explicit mathematical expression of *** authors demonstrate that our EmFace represents face image more accurate than the comparison method,with an average mean square error of 0.000888,0.000936,0.000953 on LFW,IARPA Janus Benchmark-B,and IJB-C *** results show that,EmFace has a higher representation performance on faces with various expressions,postures,and other ***,EmFace achieves reasonable performance on several face image processing tasks,including face image restoration,denoising,and transformation.

关键词： artificial neural networks face analysis image processing mathematics computing

Calcium-chelating peptides from rabbit bone collagen:characterization,identification and mechanism elucidation

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Food Science and Human Wellness 2024年第3期13卷 1485-1493页

作者： Fuhuan yuan yu Fu Liang Ma Hankun Zhu Yong yu xin Feng Yi sun Hongjie Dai xin Liu Zhengfang Liu yuhao Zhang College of Food Science Southwest UniversityChongqing 400715China Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing Chongqing 400715China Key Laboratory of Luminescence Analysis and Molecular Sensing(Southwest University) Ministry of EducationChongqing 400715China Angel Yeast Co. Ltd.Yichang 443003China

This study aimed to characterize and identify calcium-chelating peptides from rabbit bone collagen and explore the underlying chelating *** peptides and calcium were extracted from rabbit bone by instant ejection steam explosion(ICSE)combined with enzymatic hydrolysis,followed by chelation reaction to prepare rabbit bone peptide-calcium chelate(RBCP-Ca).The chelating sites were further analyzed by liquid chromatography-tandem mass(LC-MS/MS)spectrometry while the chelating mechanism and binding modes were *** structural characterization revealed that RBCP successfully chelated with calcium ***,LC-MS/MS analysis indicated that the binding sites included both acidic amino acids(Asp and Glu)and basic amino acids(Lys and Arg),Interestingly,three binding modes,namely Inter-Linking,Loop-Linking and Mono-Linking were for the first time found,while Inter-Linking mode accounted for the highest proportion(75.1%),suggesting that chelation of calcium ions frequently occurred between two ***,this study provides a theoretical basis for the elucidation of chelation mechanism of calcium-chelating peptides.

关键词： Rabbit bone Collagen peptide Peptide-calcium chelate Chelation mechanism Liquid chromatography-tandem mass(LC-MS/MS)

Neddylation Regulation of Immune Responses

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Research 2024年第3期2023卷 545-559页

作者： Hongmei Mao xin Lin Yi sun Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)of the Second Affiliated Hospital and Institute of Translational MedicineZhejiang University School of MedicineHangzhou 310029China Institute for Immunology School of MedicineTsinghua UniversityBeijing 100084China Changping Laboratory Beijing 102206China Cancer Center of Zhejiang University Hangzhou 310029China Zhejiang Provincial Clinical Research Center for Cancer HangzhouZhejiang ProvinceChina Key Laboratory of Molecular Biology in Medical Sciences HangzhouZhejiang ProvinceChina Research Center for Life Science and Human Health Binjiang Institute of Zhejiang UniversityHangzhou 310053China.

Neddylation plays a vital role in post-translational modification, intricately shaping the regulation of diverse biological processes, including those related to cellular immune responses. In fact, neddylation exerts control over both innate and adaptive immune systems via various mechanisms. Specifically, neddylation influences the function and survival of innate immune cells, activation of pattern recognition receptors and GMP-AMP synthase–stimulator of interferon genes pathways, as well as the release of various cytokines in innate immune reactions. Moreover, neddylation also governs the function and survival of antigen-presenting cells, which are crucial for initiating adaptive immune reactions. In addition, neddylation regulates T cell activation, proliferation, differentiation, survival, and their effector functions, thereby ensuring an appropriate adaptive immune response. In this review, we summarize the most recent findings in these aspects and delve into the connection between dysregulated neddylation events and immunological disorders, especially inflammatory diseases. Lastly, we propose future directions and potential treatments for these diseases by targeting neddylation.

关键词： activation thereby initiating

Dynamically switchable porphyrin-based molecular tweezer for on-off fullerene recognition

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Chinese Chemical Letters 2024年第6期35卷 283-287页

作者： Zhimin sun xin-Hui Guo yue Zhao Qing-yu Meng Li-Juan xing He-Lue sun College of Chemistry and Materials Science Hebei Key Laboratory of Organic Functional MoleculesHebei Normal UniversityShijiazhuang 050024China

Herein,a novel molecular tweezer based on 2,2'-bipyridine-bridged porphyrin subunits was constructed for efficient fullerenes *** syn conformation of the molecule,which was obtained by Zn(Ⅱ)coordination,gives rise to a proper cavity to interact with fullerene guests to form a stable 1:1 complex in toluene *** exhibits distinct binding selectivity towards C_(60)over C_(70).Moreover,the fullerene recognition capacity can be adequately suppressed by importing H_(2)PO_(4)^(-)to competitively capture Zn(Ⅱ)along with syn-anti conformational ***,the molecular tweezer regenerated to bind the fullerene by introducing the Ca^(2+)into the ***,the association-disassociation process can be switched reversibly and repeatedly.

关键词： Molecular tweezer Fullerene recognition Supramolecular chemistry Conformation conversion Coordination

Evaluation of water management on arsenic methylation and volatilization in arsenic-contaminated soils strengthened by bioaugmentation and biostimulation

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Journal of Environmental Sciences 2024年第3期137卷 515-526页

作者： Peng Chen Yi Liu Guo-xin sun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China

Arsenic(As) fate in paddy fields has been one of the most significant current issues due to the strong As accumulation potential of rice plants under fooded conditions. However,no attempt was done to explore As methylation and volatilization under non-fooded conditions. Herein, we investigated the effects of water management on As methylation and volatilization in three arsenic-contaminated soils enhanced by biostimulation with strawderived organic matter and bioaugmentation with genetic engineered Pseudomonas putida KT2440(GE P. putida). Under fooded conditions, the application of biochar(BC), rice straw(RS)and their combination(BC+RS) increased total As in porewater. However, these effects were greatly attenuated under non-fooded conditions. Compared with RS amendment alone, the combination of GE P. putida and RS further promoted the As methylation and volatilization,and the promotion percentage under non-fooded conditions were significantly higher than that under fooded conditions. The combined GE P. putida and RS showed the highest efficiency in As methylation(88 μg/L) and volatilization(415.4 μg/(kg·year)) in the non-fooded soil with moderate As contamination. Finally, stepwise multiple linear regression analysis presented that methylated As, DOC and p H in porewater were the most important factors contributing to As volatilization. Overall, our findings suggest that combination of bioaugmentation with GE P. putida and biostimulation with RS/BC+RS is a potential strategy for bioremediation of arsenic-contaminated soils by enhancing As methylation and volatilization under non-fooded conditions.

关键词： Arsenic methylation Arsenic volatilization Water management Straw incorporation Bioaugmentation