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Accelerated heterogenous ring-opening polymerization towards well-defined helical poly(N-allyl alanine)with clickable side chains

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Science China Chemistry 2024年第6期67卷 2056-2062页

作者： Anyao ma Xin Wang Sunting Xuan Zhengbiao zhang College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State Key Laboratory of Radiation Medicine and Protection Soochow UniversitySuzhou215123China

Well-defined poly(N-allyl alanine)has been synthesized by heterogenous ring-opening polymerization(HROP)of less reactive N-allyl-alanine N-carboxyanhydride,using acetic acid as the catalyst and benzylamine as the initiator,in non-polar ***,the polymerization exhibited typical features of living polymerization though both monomer(liquid)and polymer(solid)have minimal solubility in *** obtained polymer showed a stable helix structure independent of the temperatures screened,as evidenced by circular dichroism ***,the preliminary study demonstrated that the side chains can be post-functionalized through thiol-ene click chemistry with quantitative ***,this work provides guidance for the development of accelerated HROP of other liquid monomers bearing low ***,the helical and functionalizable poly(N-allyl alanine)could be a useful“clickable platform”for the design of variable biomaterials via efficient click chemistry.

关键词： heterogenous ring-opening polymerization controlled polymerization stable helix clickable N-substituted polypeptide di-substituted polypeptoid

“Blocking and rebalance”mechanism-guided design strategies of bimetallic doped 2D a-phosphorus carbide as efficient catalysts for N_(2) electroreduction

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Journal of Energy Chemistry 2024年第10期97卷 68-78,I0003页

作者： Cheng He Jianglong ma Shen Xi Wenxue zhang State Key Laboratory for Mechanical Behavior of materials School of Materials Science and EngineeringXi'an Jiaotong UniversityXian 710049ShanxiChina School of materials Science and Engineering Chang'an UniversityXi'an 710064ShaanxiChina

Compared to single atom catalysts(SACs),the introduction of dual atom catalysts(DACs)has a significantly positive effect on improving the efficiency in the electrocatalytic nitrogen reduction reaction(NRR)which provides an environmental alternative to the Haber-Bosch ***,the research on the mechanism and strategy of designing bimetallic combinations for better performance is still in its early ***,based on"blocking and rebalance"mechanism,45 combinations of bimetallic pair dopedα-phosphorus carbide(TM_(A)TM_(B)@PC)are investigated as efficient NRR catalysts through density functional theory and machine learning *** a multi-step screening,the combinations of TiV,TiFe,MnMo,and FeW exhibit highly efficient catalytic performance with significantly lower limiting potentials(-0.17,-0.18,-0.14,and-0.30 V,respectively).Excitingly,the limiting potential for CrMo and CrW combinations is 0 V,which are considered to be extremely suitable for the NRR *** mechanism of"blocking and rebalance"is revealed by the exploration of charge transfer for phosphorus atoms in electron blocking ***,the descriptorφis proposed with machine learning,which provides design strategies and accurate prediction for finding efficient *** work not only offers promising catalysts TM_(A)TM_(B)@PC for NRR process but also provides design strategies by presenting the descriptorφ.

关键词： DACs Nitrogen reduction reaction 2D a-phosphorus carbide Inherent attributes machine learning

Deployment of Edge Computing Nodes in IoT:Effective Implementation of Simulated Annealing Method Based on User Location

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China Communications 2024年第1期21卷 279-296页

作者： Junhui Zhao Ziyang zhang Zhenghao Yi Xiaoting ma Qingmiao zhang School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Information Engineering East China Jiaotong UniversityNanchang 330013China

Edge computing paradigm for 5G architecture has been considered as one of the most effective ways to realize low latency and highly reliable communication,which brings computing tasks and network resources to the edge of *** deployment of edge computing nodes is a key factor affecting the service performance of edge computing *** this paper,we propose a method for deploying edge computing nodes based on user *** the combination of Simulation of Urban Mobility(SUMO)and Network Simulator-3(NS-3),a simulation platform is built to generate data of hotspot areas in Io T *** effectively using the data generated by the communication between users in Io T scenario,the location area of the user terminal can be *** this basis,the deployment problem is expressed as a mixed integer linear problem,which can be solved by Simulated Annealing(SA)*** analysis of the results shows that,compared with the traditional method,the proposed method has faster convergence speed and better performance.

关键词： deployment problem edge computing internet of things machine learning

Predicting Acute Mountain Sickness Using Regional Sea-Level Cerebral Blood Flow

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Biomedical and Environmental Sciences 2024年第8期37卷 887-896页

作者： Hao zhang Jie Feng Shiyu zhang Wenjia Liu Lin ma Chinese PLA Medical School Beijing 100853China Department of Radiology First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy volunteers reached an altitude of 3,650 m by air after undergoing a head magnetic resonance imaging(MRI)including 3D-pCASL at sea *** CBF values of the bilateral anterior cerebral artery(ACA),middle cerebral artery(MCA),posterior cerebral artery(PCA),and posterior inferior cerebellar artery(PICA)territories and the laterality index(LI)of CBF were compared between the AMS and non-AMS *** analyses were performed to determine the relationship between CBF and AMS,and the predictive performance was assessed using receiver operating characteristic(ROC)*** The mean cortical CBF in women(81.65±2.69 mL/100 g/min)was higher than that in men(74.35±2.12 mL/100 g/min)(Pmay be used for prediction in male volunteers using non-invasive 3D-pCASL.

关键词： Acute mountain sickness High-altitude headache Cerebral blood flow Arterial spin labeling magnetic resonance imaging

Microstructures,Deformation Mechanisms and Seismic Properties of Synkinematic Migmatite from Southeastern Tibet:Insights from the Migmatitic Core of the Ailao Shan-Red River Shear Zone,Western Yunnan,China

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Journal of Earth Science 2024年第4期35卷 1149-1169页

作者： Weiwei ma Bo zhang Fulong Cai Baoyou Huang Lei zhang Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing100871China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing100085China

Seismic anisotropy originating within the continental crust is commonly used to determine the deformation and kinematic flow within active orogens and is attributed to regionally oriented mica or hornblende ***,naturally deformed rocks usually contain compositional layers(e.g.,parallel compositional banding).It is necessary to understand how both varying mineral contents and differing intensities of compositional layering influence the seismic properties of the deep *** this study,we analyzed the seismic response of migmatitic amphibolite with compositional banding *** present the microstructures,fabrics,calculated seismic velocities,and seismic anisotropies of mylonitic amphibolite from a horizontal shear layer preserved within the Ailao Shan-Red River shear zone,southwestern Yunnan,*** investigated sample is characterized by pronounced centimeter-scale compositional *** microstructures and fabrics suggest that migmatitic amphibolite rocks within deep crust may delineate regions of deformation-assisted,channelized,reactive,porous melt *** origin of compositional banding in the studied migmatitic amphibolite is attributed primarily to partial melting together with some horizontal shearing *** microfabrics and structures investigated in this study are considered to be typical for the base of active horizontal shear layers in the deep crust of southeastern *** responses are modeled by using crystal preferred orientations for minerals of the migmatitic amphibolite by applying the Voigt-Reuss-Hill homogenization *** P-wave and S-wave velocities are largely consistent in the various layers of the ***,seismic anisotropies of P-wave(AV_(p))and S-wave(AVs)are higher in the melanosomes(AV_(p)=5.6%,AV_(s)=6.83%)than those in the leucosomes and the whole rock(AV_(p)=4.2%–4.6%,AV_(s)=3.1%–3.2%).In addition,there is pronounced,S-wave splitting oblique to the foliation plane in the migm

关键词： deformation-assisted melt flow seismic anisotropy microstructure compositional banding migmatite deep crust southeastern Tibet

Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network

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Journal of Oceanology and Limnology 2024年第3期42卷 728-743页

作者： Ning zhang Junfang YANG Shanwei LIU Yi ma Jie zhang College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill *** selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency *** the same time,the combination of spectral and spatial features can improve the accuracy of oil spill *** ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong *** addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its *** with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running ***,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in *** study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit.

关键词： hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDA)

Variational Neural Inference Enhanced Text Semantic Communication System

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China Communications 2024年第7期21卷 50-64页

作者： zhang Xi zhang Yiqian Li Congduan ma Xiao School of Electronics and Communication Engineering Sun Yat-Sen UniversityShenzhen 518107China Guizhou University State Key Laboratory of Public Big Data Guiyang 550025China Shenzhen Key Laboratory of Navigation and Communication Integration Shenzhen 518107China School of Computer Science and Engineering Sun Yat-Sen UniversityGuangzhou 510006China

Recently,deep learning-based semantic communication has garnered widespread attention,with numerous systems designed for transmitting diverse data sources,including text,image,and speech,*** efforts have been directed toward improving system performance,many studies have concentrated on enhancing the structure of the encoder and ***,this often overlooks the resulting increase in model complexity,imposing additional storage and computational burdens on smart ***,existing work tends to prioritize explicit semantics,neglecting the potential of implicit *** paper aims to easily and effectively enhance the receiver's decoding capability without modifying the encoder and decoder *** propose a novel semantic communication system with variational neural inference for text ***,we introduce a simple but effective variational neural inferer at the receiver to infer the latent semantic information within the received *** information is then utilized to assist in the decoding *** simulation results show a significant enhancement in system performance and improved robustness.

关键词： deep learning semantic communication variational neural inference

Hepatitis B virus infection, infertility, and assisted reproduction

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第8期25卷 672-685页

作者： Lingjian zhang Fangfang zhang Zhiyuan ma Jie JIN Department of Infectious Diseases Affiliated Hangzhou First People’s HospitalSchool of MedicineZhejiang UniversityHangzhou 310003China Women’s Hospital School of MedicineZhejiang UniversityHangzhou 310003China Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province Affiliated Hangzhou First People’s HospitalZhejiang University School of MedicineHangzhou 310003China

Background:Hepatitis B virus(HBV)is one of the most widespread viruses worldwide and a major cause of hepatitis,cirrhosis,and hepatocellular *** studies have revealed the impacts of HBV infection on *** increasing number of infertile couples with chronic hepatitis B(CHB)virus infection choose assisted reproductive technology(ART)to meet their fertility *** the high prevalence of HBV,the effects of HBV infection on assisted reproduction treatment remain limited and ***:The aim of this study was to provide a comprehensive overview of the effect of HBV infection on fertility and discuss its effects on pregnancy outcomes,vertical transmission,pregnancy complications,and viral activity during ART ***:We conducted a literature search in PubMed for studies on HBV infection and ART published from 1996 to ***:HBV infection negatively affected fertility in both males and *** research shows that HBV infection may increase the risk of pregnancy complications in couples undergoing assisted reproduction *** impact of HBV infection on the pregnancy outcomes of ART is still *** evidence does not support that ART increases the risk of vertical transmission of HBV,while relevant studies are *** the development of ART,the risk of HBV reactivation(HBVr)is increasing,especially due to the wide application of immunosuppressive ***:Regular HBV infection screening and HBVr risk stratification and management are essential to prevent HBVr during *** determination of optimal strategy and timing of prophylactic anti-HBV therapy during ART still needs further investigation.

关键词： Assisted reproductive technology(ART) Hepatitis B virus(HBV) Immunosuppressive agent Pregnancy

In situ thermoresponsive supramolecular assembly for switchable circularly polarized luminescence

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Science China Chemistry 2024年第7期67卷 2362-2372页

作者： Menghan Pan Gong zhang Haotian ma Xiaoxiao Cheng Jieai Li Wei zhang State and Local Joint Engineering Laboratory for Novel Functional Polymeric materials Jiangsu Engineering Laboratory of Novel Functional Polymeric MaterialsSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu 241000China

The dynamic regulation of circularly polarized luminescence(CPL)holds profound significance in various fields,such as highlevel information storage and *** we developed a chiral amphiphilic molecule,CPSB-GLU-PEG350(CGP),composed of aggregation-induced emission(AIE)chromophores(Z)-4-(1-cyano-2-phenylvinyl)benzoic acid(CPSB),a chiral linker Glutamic acid and polyethylene glycol(PEG)thermoresponsive *** the self-assembled supramolecular system formed by CGP,we have achieved in-situ temperature-responsive chiral structures,facilitating the thermal control switch of the CPL *** dynamics simulations demonstrate the distinct behaviors of AIE and PEG units during the temperature-variable assembly ***,by co-assembling achiral dye molecules with CGP,we have expanded the color range of the temperature-responsive CPL assembly system in situ and confirmed the occurrence of circularly polarizedF?rster resonance energy transfer(C-FRET)phenomenon in this process,which successfully enriched the strategies for in-situ CPL control in aqueous *** addition,the contactless radiative energy transfer of CPL can also be realized in this system,exhibiting more flexible temperature regulation of the CPL *** study provides a convenient and universal strategy for the construction of dynamically smart chiroptical materials.

关键词： circularly polarized luminescence in-situ thermoresponsive supramolecular assembly energy transfer