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Chinese Journal of Chemistry 2024年第17期42卷 1993-1998页

作者： Chen Zhou Mengfu Dai Xiaoyu yin Mingyue Zhang Weijin gu Liang-An Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjingJiangsu 210023China

The stereochemical synthesis of highly substituted Danishefsky-type dienes remains unsolved in organic *** describe a simple and efficient approach for the stereoselective synthesis of Danishefsky-type trisubstituted dienes from readily available propargylic esters via Pd-catalyzed dienylation reaction through the key intermediate metallacyclobutene in a regio-,chemo-and stereoselective *** method facilitates a broad range of challenging trisubstituted dienes with a high level of stereocontrol.

关键词： Propargylic ester Dienylation Diene Stereoselectivity Cycloaddition Palladium β-H elimination Regioselectivity

Orbital angular momentum-mediated machine learning for high-accuracy mode-feature encoding

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Light(Science & Applications) 2024年第3期13卷 466-477页

作者： Xinyuan fang Xiaonan Hu Baoli Li Hang Su Ke Cheng Haitao Luan Min gu Institute of Photonic Chips University of Shanghai for Science and TechnologyShanghai 200093China Centre for Artificial-Intelligence Nanophotonics School of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

Machine learning with optical neural networks has featured unique advantages of the information processing including high speed,ultrawide bandwidths and low energy consumption because the optical dimensions(time,space,wavelength,and polarization)could be utilized to increase the degree of ***,due to the lack of the capability to extract the information features in the orbital angular momentum(OAM)domain,the theoretically unlimited OAM states have never been exploited to represent the signal of the input/output nodes in the neural network ***,we demonstrate OAM-mediated machine learning with an all-optical convolutional neural network(CNN)based on Laguerre-Gaussian(LG)beam modes with diverse diffraction *** proposed CNN architecture is composed of a trainable OAM mode-dispersion impulse as a convolutional kernel for feature extraction,and deep-learning diffractive layers as a *** resultant OAM mode-dispersion selectivity can be applied in information mode-feature encoding,leading to an accuracy as high as 97.2%for MNIST database through detecting the energy weighting coefficients of the encoded OAM modes,as well as a resistance to eavesdropping in point-to-point free-space ***,through extending the target encoded modes into multiplexed OAM states,we realize all-optical dimension reduction for anomaly detection with an accuracy of 85%.Our work provides a deep insight to the mechanism of machine learning with spatial modes basis,which can be further utilized to improve the performances of various machine-vision tasks by constructing the unsupervised learning-based auto-encoder.

关键词： polarization mode momentum

A Methodology for Assessing Axial Compressor Stability with Inlet Temperature Ramp Distortion

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Journal of Thermal Science 2024年第3期33卷 856-871页

作者： SUN Dakun gu Benhao NING fangfei fang Yibo DONG Xu XU Dengke SUN Xiaofeng School of Energy and Power Engineering Beihang UniversityBeijing102206China Research Institute of Aero-engine Beihang UniversityBeijing102206China

Based on a small perturbation stability model for periodic flow,the effects of inlet total temperature ramp distortion on the axial compressor are investigated and the compressor stability is quantitatively *** the beginning,a small perturbation stability model for the periodic flow in compressors is proposed,referring to the governing equations of the Harmonic Balance *** stability model is validated on a single-stage low-speed compressor TA36 with uniform inlet ***,the unsteady flow of TA36 with different inlet total temperature ramps and constant back pressure is simulated based on the Harmonic Balance *** on these simulations,the compressor stability is analyzed using the proposed small perturbation ***,the Dynamic Mode Decomposition method is employed to accurately extract pressure *** two parameters of the temperature ramp,ramp rate and Strouhal number,are discussed in this *** results indicate the occurrence and extension of hysteresis loops in the rows,and a decrease in compressor stability with increasing ramp *** performance is divided into two phases,stable and limit,based on the ramp ***,the model predictions suggest that a decrease in period length and an increase in Strouhal number lead to improved compressor *** DMD results imply that for compressors with inlet temperature ramp distortion,the increase of high-order modes and oscillations at the rotor tip is always the signal of decreasing stability.

关键词： axial compressor stability small perturbation model inlet temperature ramp distortion harmonic balance method dynamic mode decomposition method

Assessment of Crop Yield in China Simulated by Thirteen Global Gridded Crop Models

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Advances in Atmospheric Sciences 2024年第3期41卷 420-434页

作者： Dezhen yin fang LI Yaqiong LU Xiaodong ZENG Zhongda LIN Yanqing ZHOU International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

Global gridded crop models(GGCMs) have been broadly applied to assess the impacts of climate and environmental change and adaptation on agricultural production. China is a major grain producing country, but thus far only a few studies have assessed the performance of GGCMs in China, and these studies mainly focused on the average and interannual variability of national and regional yields. Here, a systematic national-and provincial-scale evaluation of the simulations by13 GGCMs [12 from the GGCM Intercomparison(GGCMI) project, phase 1, and CLM5-crop] of the yields of four crops(wheat, maize, rice, and soybean) in China during 1980–2009 was carried out through comparison with crop yield statistics collected from the National Bureau of Statistics of China. Results showed that GGCMI models generally underestimate the national yield of rice but overestimate it for the other three crops, while CLM5-crop can reproduce the national yields of wheat, maize, and rice well. Most GGCMs struggle to simulate the spatial patterns of crop yields. In terms of temporal variability, GGCMI models generally fail to capture the observed significant increases, but some can skillfully simulate the interannual variability. Conversely, CLM5-crop can represent the increases in wheat, maize, and rice, but works less well in simulating the interannual variability. At least one model can skillfully reproduce the temporal variability of yields in the top-10 producing provinces in China, albeit with a few exceptions. This study, for the first time, provides a complete picture of GGCM performance in China, which is important for GGCM development and understanding the reliability and uncertainty of national-and provincial-scale crop yield prediction in China.

关键词： global gridded crop model historical crop yield China multi-model evaluation

Spatio-temporal Reallocation Method for Energy Management in Edge Data Centers

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 1901-1910页

作者： Junlong Li Chenghong gu Lurui fang Xiangyu Wei Yuanbin Zhu Yue Xiang University of Bath Bath BA27AYUK Department of Electrical and Electronic Engineering Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China College of Electrical Engineering Sichuan UniversityChengdu 610065China

Edge data centers(EDCs)have been widely developed recently to supply delay-sensitive computing services,which impose prohibitively increasing electricity costs for EDC *** paper presents a new spatiotemporal reallocation(STR)method for energy management in *** method uses spare resources,including servers and energy storage systems(ESSs)within EDCs to reduce energy costs based on both spatial and temporal features of spare *** solution:1)reallocates flexible workload between EDCs within one cluster;and 2)coordinates the electricity load of data processing,ESSs and distributed energy resources(DERs)within one EDC cluster to gain benefits from flexible electricity *** addition,this paper for the first time develops a Bit-Watt transformation to simplify the STR method and represent the relationship between data workload and electricity consumption of *** studies justifying the developed STR method delivers satisfying cost reductions with *** STR method fully utilized both spatial and temporal features of spare resources in EDCs to gain benefits from 1)varying electricity tariffs,and 2)maximumly consuming DER generation.

关键词： Edge data centers electricity costs reduction power control power market workload migration

Symmetrization of quasi-regular patterns with periodic tilting of regular polygons

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Computational Visual Media 2024年第3期10卷 559-576页

作者： Zhengzheng yin Yao Jin Zhijian fang Yun Zhang Huaxiong Zhang Jiu Zhou Lili He School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Provincial Innovation Center of Advanced Textile Technology Shaoxing 312000China School of Media Engineering Communication University of ZhejiangHangzhou 310018China

Computer-generated aesthetic patterns arewidely used as design materials in various fields. Themost common methods use fractals or dynamicalsystems as basic tools to create various patterns. Toenhance aesthetics and controllability, some researchershave introduced symmetric layouts along with thesetools. One popular strategy employs dynamical systemscompatible with symmetries that construct functionswith the desired symmetries. However, these aretypically confined to simple planar symmetries. Theother generates symmetrical patterns under theconstraints of tilings. Although it is slightly moreﬂexible, it is restricted to small ranges of tilingsand lacks textural variations. Thus, we proposed anew approach for generating aesthetic patterns bysymmetrizing quasi-regular patterns using general kuniformtilings. We adopted a unified strategy toconstruct invariant mappings for k-uniform tilings thatcan eliminate texture seams across the tiling ***, we constructed three types of symmetriesassociated with the patterns: dihedral, rotational, andreﬂection symmetries. The proposed method can beeasily implemented using GPU shaders and is highlyefficient and suitable for complicated tiling with regularpolygons. Experiments demonstrated the advantages of our method over state-of-the-art methods in terms ofﬂexibility in controlling the generation of patterns withvarious parameters as well as the diversity of texturesand styles.

关键词： quasi-regular patterns(QRP) k-uniform tilings invariant mappings symmetry aesthetic patterns

Advancing Underlying Cause of Death Inference Through Wide and Deep Model

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China CDC weekly 2024年第21期6卷 487-492,I0009-I0014页

作者： Xin fang Shaofen Huang Yanrong yin Tiehui Chen Zhijun Liao Wenling Zhong Department for Chronic and Noncommunicable Disease Control and Prevention Fujian Provincial Center for Disease Control and PreventionFuzhou CityFujian ProvinceChina Department of Biochemistry and Molecular Biology School of Basic Medical SciencesFujian Medical UniversityFuzhou CityFujian ProvinceChina

Introduction:Accurately filling out death certificates is essential for death ***,manually determining the underlying cause of death is often *** this study,we investigate the Wide and Deep framework as a method to improve the accuracy and reliability of inferring the underlying cause of ***:Death report data from national-level cause of death surveillance sites in Fujian Province from 2016 to 2022,involving 403,547 deaths,were *** Wide and Deep embedded with Convolutional Neural Networks(CNN)was *** performance was assessed using weighted accuracy,weighted precision,weighted recall,and weighted area under the curve(AUC).A comparison was made with XGBoost,CNN,Gated Recurrent Unit(GRU),Transformer,and GRU with ***:The Wide and Deep achieved strong performance metrics on the test set:precision of 95.75%,recall of 92.08%,F1 Score of 93.78%,and an AUC of 95.99%.The model also displayed specific F1 Scores for different cause-of-death chain lengths:97.13%for single causes,95.08%for double causes,91.24%for triple causes,and 79.50%for quadruple ***:The Wide and Deep significantly enhances the ability to determine the root causes of death,providing a valuable tool for improving causeof-death surveillance *** artificial intelligence(AI)in this field is anticipated to streamline death registration and reporting procedures,thereby boosting the precision of public health data.

关键词： thereby boosting precise

Research on Hepatocyte Regulation of PCSK9-LDLR and Its Related Drug Targets

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Chinese Journal of Integrative Medicine 2024年第7期30卷 664-672页

作者： LIU Su-su YU Tong QIAO Yan-fang gu Shu-xiao CHAI Xin-lou School of Traditional Chinese Medicine Beijing University of Traditional Chinese MedicineBeijing102401China

The prevalence of hyperlipidemia has increased significantly due to genetic, dietary, nutritional and pharmacological factors, and has become one of the most common pathological conditions in humans. Hyperlipidemia can lead to a range of diseases such as atherosclerosis, stroke, coronary heart disease, myocardial infarction, diabetes, and kidney failure, etc. High circulating low-density lipoprotein cholesterol (LDL-C) is one of the causes of hyperlipidemia. LDL-C in the blood binds to LDL receptor (LDLR) and regulates cholesterol homeostasis through endocytosis. In contrast, proprotein convertase subtilisin/kexin type 9 (PCSK9) mediates LDLR degradation via the intracellular and extracellular pathways, leading to hyperlipidemia. Targeting PCSK9-synthesizing transcription factors and downstream molecules are important for development of new lipid-lowering drugs. Clinical trials regarding PCSK9 inhibitors have demonstrated a reduction in atherosclerotic cardiovascular disease events. The purpose of this review was to explore the target and mechanism of intracellular and extracellular pathways in degradation of LDLR and related drugs by PCSK9 in order to open up a new pathway for the development of new lipid-lowering drugs.

关键词： hyperlipidemia proprotein convertase subtilisin/kexin type 9 low-density lipoprotein receptor intracellular pathway extracellular pathway

Tissue adhesive,ROS scavenging and injectable PRP-based‘plasticine’for promoting cartilage repair

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Regenerative Biomaterials 2024年第1期3卷 94-107页

作者： Shiao Li Dawei Niu Haowei fang Yancheng Chen Jinyan Li Kunxi Zhang Jingbo yin Peiliang Fu Department of Orthopedics Shanghai Changzheng HospitalNaval Medical UniversityShanghai 200003P.R.China Department of Polymer Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444P.R.China

Platelet-rich plasma(PRP)that has various growth factors has been used clinically in cartilage ***,the short residence time and release time at the injury site limit its therapeutic *** present study fabricated a granular hydrogel that was assembled from gelatin microspheres and tannic acid through their abundant hydrogen *** microspheres with the gelatin concentration of 10wt%and the diameter distribution of 1-10 lm were used to assemble by tannic acid to form the granular hydrogel,which exhibited elasticity under low shear strain,but flowability under higher shear *** viscosity decreased with the increase in shear ***,the granular hydrogel exhibited self-healing feature during rheology ***,granular hydrogel carrying PRP not only exhibited well-performed injectability but also performed like a‘plasticine’that possessed good *** granular hydrogel showed tissue adhesion ability and reactive oxygen species scavenging *** hydrogel carrying PRP transplanted to full-thickness articular cartilage defects could integrate well with native cartilage,resulting in newly formed cartilage articular fully filled in defects and well-integrated with the native cartilage and subchondral *** unique features of the present granular hydrogel,including injectability,plasticity,porous structure,tissue adhesion and reactive oxygen species scavenging provided an ideal PRP carrier toward cartilage tissue engineering.

关键词： cartilage regeneration granular hydrogel gelatin tannic acid PRP

Efficient electroreduction of nitrate via enriched active phases on copper-cobalt oxides

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Chinese Chemical Letters 2024年第4期35卷 204-209页

作者： Ling fang Sha Wang Shun Lu Fengjun yin Yujie Dai Lin Chang Hong Liu Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing 100049China

Electrochemical conversion of nitrate(NO_(3)~-) to ammonia(NH_(3)) can target two birds with one stone well, in NO_(3)^(-)-containing sewage remediation and sustainable NH_(3) production. However, single metalbased catalysts are difficult to drive high-efficient NO_(3)~- removal due to the multi-electron transfer ***, we present a tandem catalyst with simple structure, Cu-Co binary metal oxides(Cu-Co-O), by engineering intermediate phases as catalytic active species for NO_(3)~- conversion. Electrochemical evaluation,X-ray photoelectron spectroscopy, and in situ Raman spectra together suggest that the newly-generated Cu-based phases was prone to NO_(3)~- to NO_(2)~- conversion, then NO_(2)~- was reduced to NH_(3) on Co-based species. At an applied potential of -1.1 V vs. saturated calomel electrode, the Cu-Co-O catalyst achieved NO_(3)~- -N removal of 90% and NH_(3) faradaic efficiency of 81% for 120 min in 100 m L of 50 mg/L NO_(3)~- -N,consuming only 0.69 k Wh/mol in a two-electrode system. This study provides a facile and efficient engineering strategy for developing high-performance catalysts for electrocatalytic nitrate conversion.

关键词： NO_(3)^(-)-containing sewage remediation Electrocatalytic reduction Copper-cobalt oxides Tandem reactivity Enriched active phases