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Phosphine/Benzocyclone-based Neutral Nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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chinese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang li Pan Vladislav A.Tuskaev Svetlana ch.Gagieva Yue-Sheng li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(Ni1: Ar = Ph;Ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);Ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes Ni2 and Ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol Ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex Ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol Ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： Neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

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Single-pilot operations in commercial flight:Effects on neural activity and visual behaviour under abnormalities and emergencies

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chinese Journal of Aeronautics 2024年第8期37卷 277-292页

作者： Qinbiao li chun-Hsien chEN Kam K.H.ng Xin YUAN cho Yin YIU Human Factors and Ergonomics Laboratory Department of Aeronautical and Aviation EngineeringThe Hong Kong Polytechnic UniversityHong Kong Special Administrative Region 100872China School of Mechanical&Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

With cutting-edge technologies and considering airline human-resource-saving,a single pilot in commercial jets could be technically *** changes in captains’natural behaviours are initially required to comprehend the specific safe human performance envelope for safeguarding single-pilot flight,particularly in high-risk *** paper investigates how captains’performance transforms for fixing emergencies when operating from Dual-Pilot Operations(DPO)to Single-Pilot Operations(SPO)through a physiological-based *** pilots flew an emergency-included flight with/without first officers’*** neural activities and scanning behaviours were recorded using a 32-channel Electroencephalogram(EEG)and glasses-based eye tracker,with the observation and post-experiment questionnaires to evaluate the flight operations and pilots’*** alone,there was a significantly increased cortical activity in h and b waves over the frontal,parietal,and temporal lobes during the more complicated emergencies,and pilots focused less on the primary flight display while spending significantly more time scanning the other *** physiological fluctuating patterns associated with risky operations in SPO were highlighted by cross-correlating multimodal *** experimental-based noteworthy insights may wish to inform commercial SPO measures to lessen the persistent physiological fluctuation,assisting airlines in creating SPO-oriented intelligent flight systems to give captains adequate support for assuring safer air transportation.

关键词： Aviation engineering Single pilot operations Behaviour changes Eye tracker Electroencephalogram

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Jetting-based bioprinting:process,dispense physics,and applications

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Bio-Design and Manufacturing 2024年第5期7卷 771-799页

作者： Wei Long ng Viktor Shkolnikov Singapore Centre for 3D Printing(SC3DP) School of Mechanical and Aerospace EngineeringNanyang Technological University(NTU)Singapore 639798Singapore HP Inc. Palo AltoCA 94304USA

Jetting-based bioprinting facilitates contactless drop-on-demand deposition of subnanoliter droplets at well-defined positions to control the spatial arrangement of cells,growth factors,drugs,and biomaterials in a highly automated layer-by-layer fabrication *** to its immense versatility,jetting-based bioprinting has been used for various applications,including tissue engineering and regenerative medicine,wound healing,and drug development.A lack of in-depth understanding exists in the processes that occur during jetting-based *** review paper will comprehensively discuss the physical considerations for bioinks and printing conditions used in jetting-based *** first present an overview of different jetting-based bioprinting techniques such as inkjet bioprinting,laser-induced forward transfer bioprinting,electrohydrodynamic jet bioprinting,acoustic bioprinting and microvalve ***,we provide an in-depth discussion of various considerations for bioink formulation relating to cell deposition,print chamber design,droplet formation and droplet ***,we highlight recent accomplishments in jetting-based *** present the advantages and challenges of each method,discuss considerations relating to cell viability and protein stability,and conclude by providing insights into future directions of jetting-based bioprinting.

关键词： 3D bioprinting Biofabrication Jetting-based Dispense physics Machine learning

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Weakly Supervised Object Localization with Background Suppression Erasing for Art Authentication and Copyright Protection

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Machine Intelligence Research 2024年第1期21卷 89-103页

作者： chaojie Wu Mingyang li Ying Gao Xinyan Xie Wing W.Y.ng Ahmad Musyafa School of Computer Science and Engineering South China University of TechnologyGuangzhou 511442China Guangdong Provincial Key Laboratory of Artificial Intelligence in Medical Image Analysis and Application Guangdong Provincial People's HospitalGuangzhou 510180China

The problem of art forgery and infringement is becoming increasingly prominent,since diverse self-media contents with all kinds of art pieces are released on the Internet every *** art paintings,object detection and localization provide an efficient and ef-fective means of art authentication and copyright ***,the acquisition of a precise detector requires large amounts of ex-pensive pixel-level *** alleviate this,we propose a novel weakly supervised object localization(WSOL)with background su-perposition erasing(BSE),which recognizes objects with inexpensive image-level ***,integrated adversarial erasing(IAE)for vanilla convolutional neural network(CNN)dropouts the most discriminative region by leveraging high-level semantic ***,a background suppression module(BSM)limits the activation area of the IAE to the object region through a self-guidance ***,in the inference phase,we utilize the refined importance map(RIM)of middle features to obtain class-agnostic loc-alization *** experiments are conducted on paintings,CUB-200-2011 and ILSVRC to validate the effectiveness of our BSE.

关键词： Weakly supervised object localization erasing method deep learning computer vision art authentication and copyright protection

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Electrolyte Effect on Photoetching of Gallium Nitride

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Nanomanufacturing and Metrology 2024年第1期7卷 61-74页

作者： Huiqiang liang Zhenghao Wei Jiongchong Fang Yanming li changli li Zhirun Xie Yun Hau ng Guosong Zeng Shenzhen Key Laboratory of Intelligent Robotics and Flexible Manufacturing Systems Southern University of Science and TechnologyShenzhen 518055People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China School of Materials Sun Yat-Sen UniversityGuangzhou 510275People’s Republic of China School of Energy and Environment City University of Hong KongKowloon 999077Hong Kong SARPeople’s Republic of China City University of Hong Kong Shenzhen Research Institute Shenzhen Hi-Tech Industrial ParkNanshan DistrictShenzhen 518000People’s Republic of China SUSTech Energy Institute for Carbon Neutrality Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

The limited material removal rate of conventional chemical mechanical polishing(CMP)significantly hinders the fabrica-tion efficiency and surface quality,thereby preventing the development of gallium nitride(GaN)-based ***,the incorporation of photoelectrochemistry in CMP has garnered increasing attention because of its potential to enhance the quality and efficiency of the GaN ***,a considerable gap still exists in the comprehensive understanding of the specific photoelectrochemical(PEC)behavior of ***,we report the influence of the electrolyte on the PEC etching of *** acids and bases were tested,with their pH being carefully *** concentrations of the cations and anions were also *** results showed that photocorrosion/photoetching was more pronounced in sulfuric acid,phosphoric acid,and nitric acid environments than in alkaline environments,but it was less pronounced in hydrochloric ***,the effects of pH and anion concentration on photoetching were investigated,and the results revealed that pho-toetching in acidic environments weakened with increasing pH levels and diminished with increasing sulfate *** underlying reasons contributing to this observation were *** findings provide ideas for improving the pho-toetching efficiency of GaN,thereby enriching the photoelectrochemical mechanical polishing(PECMP)technology of GaN.

关键词： GaN Photoelectrochemistry Photoetching pH

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Dysfunction of synaptic endocytic trafficking in Parkinson's disease

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Neural Regeneration Research 2024年第12期19卷 2649-2660页

作者： Xin Yi ng Mian Cao Programme in Neuroscience and Behavioural Disorders Duke-NUS Medical SchoolSingaporeSingapore Department of Physiology National University of SingaporeSingaporeSingapore

Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the *** precise reasons behind the specific degeneration of these dopamine neurons remain largely *** investigations have identified over 20 causative PARK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's ***,several of these genes are linked to the synaptic vesicle recycling process,particularly the clathrinmediated endocytosis *** suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease,followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a"dying back"***,several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively *** models faithfully recapitulate certain Parkinson's disease-like features at the animal,circuit,and cellular levels,and exhibit defects in synaptic membrane trafficking,further supporting the findings from human genetics and clinical *** this review,we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins:auxilin(DNAJC6/PARK19)and synaptojanin 1(SYNJ1/PARK20).The mouse models carrying these two PARK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic ***,we will delve into the involvement of several clathrin-mediated endocytosis-related proteins(GAK,endophilin A1,SAC2/INPP5 F,synaptotagmin-11),identified as Parkinson's disease risk factors through genome-wide association studies,in Parkinson's disease *** will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins(alpha-synuclein(PARK1/4),Parkin(PARK2),and LRRK2(PARK

关键词： autophagy auxilin/PARK19 clathrin-mediated endocytosis dopamine neurons neurodegeneration nigrostriatal pathway Parkinson's disease synaptic vesicle recycling synaptojanin1/PARK20

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Structural insight into palladium-nickel clusters over mordenite zeolite for carbene-insertion reaction

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Frontiers of chemical Science and Engineering 2024年第9期18卷 89-99页

作者： Guangchao li Ping-Luen Baron Ho Bryan Kit Yue ng Tai-Sing Wu Pawel Rymarz Shik chi Edman Tsang Department of Applied Biology and chemical Technology The Hong Kong Polytechnic UniversityHong Kong 999077China Department of chemistry University of OxfordOxford OX13QRUK Synchrotron Radiation Research Center Hsinchu 30076China

The advancement of heterogeneous catalysts incorporating metal clusters in the nanometric size range has garnered significant attention due to their extraordinary catalytic activity and *** detailed characterization and understanding of the atomic structure of these metal clusters within catalysts is crucial for elucidating the underlying reaction *** the present study,a distinctive three-atom PdNi cluster,characterized by two Pd atoms at terminal positions and a central Ni atom,was synthesized over mordenite *** presence of atomic PdNi clusters within the eight-membered ring side pocket area was confirmed by multiple advanced analytical techniques,including magic-angle spinning nuclear magnetic resonance spectroscopy,synchrotron X-ray powder diffraction,extended X-ray absorption fine structure spectroscopy,and high-angle annular dark-field scanning transmission electron *** catalytic activity of the confined active species was examined by the carbene-mediated reactions of ethyl-2-diazoacetate to ethyl-2-methoxyacetate as a model *** to the Pd-mordenite and Ni-mordenite,the PdNi-mordenite catalyst incorporates a PdNi cluster,which demonstrates a superior performance,achieving 100%conversion and high selectivity under the same reaction *** study elucidates the potential of constructing bimetallic clusters in zeolites,providing valuable insights for developing new heterogeneous catalysts applicable to a wide range of catalytic processes.

关键词： zeolite metal cluster synchrotron X-ray diffraction carbene-mediated reaction

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Topology modulation of tetraphenylethylene graphdiyne at a liquid-liquid interface

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Nano Research 2024年第6期17卷 4661-4667页

作者： Tingting Xu Pei Wen ng Shaofei Wu Danjun Fu Yunhan Ma Yao liu lidao li Xiaofei Zhang Jun Zhu Department of chemistry National University of SingaporeSingapore 117543Singapore Institute of Materials Research and Engineering(IMRE) Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore

Monomers with low symmetries can form different topological structures in the preparation of organic two-dimensional(2D)***,it remains challenging to modulate the topologies in practical *** theoretical insights into the formation energy of potential structural configurations,we report the topology modulation of a graphdiyne(GDY)derivative constructed from two-fold symmetric tetrakis(4-ethynylphenyl)ethene precursor by changing solvent combinations in a liquid-liquid interfacial *** aqueous-organic(water-dichloromethane)interface afforded GDY with a kagome topology while a rhombic topology was formed at an organic-organic(hexane-acetonitrile)interface.A comprehensive evaluation of their structures and optoelectronic properties was conducted through various characterization techniques and theoretical *** study provided new insights to modulate the topology of not only GDY but also other framework structures and obtain topologically pure materials in situations where different topologies are possible during practical synthesis.

关键词： graphdiyne derivative tetraphenylethylene topology modulation aggregation-induced emission(AIE)two-dimensional(2D)polymers interfacial synthesis

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Geochemistry and mineral chemistry of the armoor granitoids,eastern dharwar craton: implications for the redox conditions and tectono-magmatic environment

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Acta Geochimica 2024年第1期43卷 110-133页

作者： A.Ajay Kumar ch.Ashok Department of Geology Osmania UniversityHyderabad 500007India CSIR-National Geophysical Research Institute UppalHyderabad 500007India

The mineralogical and geochemical characteristics of the K-rich granites from the Armoor granitic rocks in the northeastern portion of the Eastern Dharwar Craton(EDC) are *** order to understand its physicochemical conditions,the petrogenesis of the granitoid was explained from biotite chemistry and geochemical *** of mineral chemistry expose that compositionally,K-feldspar and plagioclase in Armoor granite rocks range from An0,Ab_(3-5.9),Or_(94-96.9) and An_(5-29,-Ab71.9-94.9),Or_(0-1.5),*** mineral chemistry of biotite crystals exhibits composition that varies from primary to re-equilibrated primary *** biotites from the Armoor granites generally exhibit an I-type trend,with calc-alkaline parental magma in a subduction *** chemistry of granites displays magnetite(oxidized)series nature,which has oxygen fugacity(fO_(2))=-15.1 to-16.7(log_(10) bar),under high oxidizing *** and pressure estimates for the crystallization of Armoor granites based on biotite composition are T=612-716 ℃ and 1.0-0.4 kbar,***,these rocks are metaluminous to slightly peraluminous and magnesian,with calc-alkaline potassiumrich *** the chondrite normalized REE diagram,the granites have positive europium anomalies;rich Sr/Y,(Dy/Yb)_(N) ratios and reduced Mg#,Rb/Sr,Rb,Sr indicate that the melting of earlier rocks,crystal accumulation and residual garnet source formed at high *** examined granites show that they are produced from the melting of crustal ***,the extensive analyses of the described Armoor granite suggest that they were produced by crust sources and developed under oxidizing conditions in subduction setting.

关键词： Armoor granites Oxygen fugacity Crystal accumulation Remelting Subduction

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Prevalence and risk factors of depression among patients with perianal fistulizing Crohn’s disease

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World Journal of Psychiatry 2024年第5期14卷 715-725页

作者： Jing li Wing-Yi ng li-chao Qiao Fen Yuan Xing Lan li-Bei Zhu Bo-lin Yang Zhong-Qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Acupuncture and Rehabilitation Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Colorectal Surgery Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BACKGROUND Psychological distress,especially depression,associated with perianal fistulizing Crohn’s disease(PFCD)is widespread and ***,there is a surprising paucity of studies to date that have sought to identify the prevalence and risk factors of depression associated with *** To estimate the prevalence of depressive symptoms and investigate the depression-related risk factors in patients with *** The study was conducted in the form of survey and clinical data collection via questionnaire and specialized medical *** symptoms,life quality,and fatigue severity of patients with PFCD were assessed by Patient Health Questionnaire-9,Inflammatory Bowel Disease Patient Quality of life Questionnaire(IBDQ),and Inflammatory Bowel Disease(IBD)Fatigue Patient Self-assessment *** basic demographic information,overall disease features,perianal clinical information,and laboratory inflammation indicators were also *** regression analysis was ultimately used to ascertain the risk factors of depression associated with *** A total of 123 patients with PFCD were involved,and 56.91%were suffering from *** to multivariate logistic regression analysis,Perianal Disease Activity Index(PDAI)score[odds ratio(OR)=0.69,95%confidence interval(CI):0.50 to 0.95],IBDQ score(OR=0.93,95%CI:0.88 to 0.97),modified Van Assche index(OR=1.24,95%CI:1.01 to 1.53),and IBD Fatigue score(OR=1.72,95%CI:1.23 to 2.42)were independent risk factors of depression-related prevalence among patients with PFCD(Plinear regression analysis revealed that the increasing perianal modified Van Assche index(βvalue=0.166,95%CI:0.02 to 0.31)and decreasing IBDQ score(βvalue=-0.116,95%CI:-0.14 to-0.09)were independently associated with the severity of depression(Pche index,quality of life,and fatigue severity

关键词： Crohn’s disease Fistula Depression Inflammatory bowel diseases Risk factors

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