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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang shi Yi Wan Yongqiang Zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions

Quantitative Green's function estimates for lattice quasi-periodic Schrodinger operators

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Science China Mathematics 2024年第5期67卷 1011-1058页

作者： Hongyi Cao Yunfeng shi Zhifei Zhang School of Mathematical Sciences Peking UniversityBeijing 100871China School of Mathematics Sichuan UniversityChengdu 610064China

In this paper,we establish quantitative Green’s function estimates for some higher-dimensional lattice quasi-periodic(QP)Schrodinger *** resonances in the estimates can be described via a pair of symmetric zeros of certain functions,and the estimates apply to the sub-exponential-type non-resonance *** the application of quantitative Green’s function estimates,we prove both the arithmetic version of Anderson localization and the finite volume version of(1/2-)-Holder continuity of the integrated density of states(IDS)for such QP Schrodinger *** gives an affirmative answer to Bourgain’s problem in Bourgain(2000).

关键词： Holder continuity of the IDS quantitative Green's function estimates quasi-periodic Schrodinger operators arithmetic Anderson localization multi-scale analysis

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Geant4 simulation of fast-electron bremsstrahlung imaging at the HL-3 tokamak

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Nuclear Science and Techniques 2024年第9期35卷 213-229页

作者： shi-Kui Cheng Yi-Po Zhang Yue-Jiang shi Jie Zhang Shuai Guan Hong-Bing Xu Qiu-Lei Yang College of Science Chongqing University of TechnologyChongqing 400054China Chongqing Key Laboratory of New Energy Storage Materials and Devices Chongqing 400054China Southwestern Institute of Physics Chengdu 610041China Hebei Key Laboratory of Compact Fusion Langfang 065001China ENN Science and Technology Development Co. Ltd.Langfang 065001China

To further research on high-parameter plasma,we plan to develop a two-dimensional hard X-ray(HXR)imaging system at the HL-3 tokamak to measure HXRs with energies ranging from 20 to 300 *** application of an array-structured detector ensures that this system can measure HXR-radiation spectra from the entire plasma cross ***,it is suitable for the study of fast-electron physics,such as radio-frequency wave current drives,fast electrons driving instabilities,and plasma disruptions in fusion *** this study,we develop a simulation for calculating fast-electron bremsstrahlung in the HL-3 tokamak based on the Monte Carlo simulation code Geant4,in which the plasma geometry and forward scattering of fast-electron bremsstrahlung are *** preliminary calculation results indicate that the HXR energy deposi-tion on the detector is symmetrically distributed,even though the plasma distribution is asymmetric owing to the toroidal *** simulation results are helpful in constructing the relationship between the energy deposition on the detector and parameter distribution on the plasma cross section during HL-3 *** is beneficial for the reconstruction of the fast-electron-distribution function and for optimizing the design of the HXR-imaging system.

关键词： Geant4 simulation HL-3 tokamak Fast-electron bremsstrahlung Hard X-ray imaging

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Nano-Au-decorated hierarchical porous cobalt sulfide derived from ZIF-67 toward optimized oxygen evolution catalysis:Important roles of microstructures and electronic modulation

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Carbon Energy 2024年第5期6卷 1-14页

作者： Hongyu Gong Guanliang Sun Wenhua shi Dongwei Li Xiangjun Zheng Huan shi Xiu Liang Ruizhi Yang Changzhou Yuan Department of New Energy Materials School of Environmental and Chemical EngineeringJiangsu University of Science and TechnologyZhenjiangJiangsuChina Advanced Materials Institute Qilu University of Technology(Shandong Academy of Sciences)JinanShandongChina Shandong Saikesaisi Hydrogen Energy Co. Ltd.JinanShandongChina Department of Materials Science and Engineering School of Materials Science&EngineeringUniversity of JinanJinanShandongChina Department of New Energy Science and Engineering College of EnergySoochow Institute for Energy and Materials InnovationsSoochow UniversitySuzhouJiangsuChina

Enhancing both the number of active sites available and the intrinsic activity of Co-based electrocatalysts simultaneously is a desirable ***,a ZIF-67-derived hierarchical porous cobalt sulfide decorated by Au nanoparticles(NPs)(denoted as HP-Au@CoxSy@ZIF-67)hybrid is synthesized by low-temperature sulfuration *** well-defined macroporous-mesoporous-microporous structure is obtained based on the combination of polystyrene spheres,as-formed CoxSy nanosheets,and ZIF-67 *** novel three-dimensional hierarchical structure significantly enlarges the three-phase interfaces,accelerating the mass transfer and exposing the active centers for oxygen evolution *** electronic structure of Co is modulated by Au through charge transfer,and a series of experiments,together with theoretical analysis,is performed to ascertain the electronic modulation of Co by ***,HP-Au@CoxSy@ZIF-67 catalysts with different amounts of Au were synthesized,wherein Au and NaBH4 reductant result in an interesting“competition effect”to regulate the relative ratio of Co^(2+)/Co^(3+),and moderate Au assists the electrochemical performance to reach the highest ***,the optimized HP-Au@CoxSy@ZIF-67 exhibits a low overpotential of 340 mV at 10 mA cm^(-2)and a Tafel slope of 42 mV dec-1 for OER in 0.1 M aqueous KOH,enabling efficient water splitting and Zn-air battery *** work here highlights the pivotal roles of both microstructural and electronic modulation in enhancing electrocatalytic activity and presents a feasible strategy for designing and optimizing advanced electrocatalysts.

关键词： Au nanoparticles cobalt sulfide electronic modulation hierarchical porous structure oxygen evolution reaction

Mechanism of plant-soil feedback in a degraded alpine grassland on the Tibetan Plateau

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JOURNAL OF PLANT ECOLOGY 2024年第2期17卷 188-199页

作者： Zhou, Tiancai Sun, Jian shi, Peili Chinese Acad Sci Inst Geog Sci & Nat Resources Res Key Lab Ecosyst Network Observat & Modelling Beijing 100101 Peoples R China Chinese Acad Sci Inst Tibetan Plateau Res State Key Lab Tibetan Plateau Earth Syst Resources Beijing 100101 Peoples R China Minist Educ Key Lab Biodivers & Environm Qinghai Tibet Plateau Lhasa 850011 Peoples R China Tibet Res Acad Ecoenvironm Sci Lhasa 850000 Peoples R China Univ Chinese Acad Sci Coll Resources & Environm Beijing 100049 Peoples R China

Although biotic and abiotic factors have been confirmed to be critical factors that affect community dynamics, their interactive effects have yet to be fully considered in grassland degradation. Herein, we tested how soil nutrients and microbes regulated plant-soil feedback (PSF) in a degraded alpine grassland. Our results indicated that soil total carbon (STC; from 17.66 to 12.55 g/kg) and total nitrogen (STN; from 3.16 to 2.74 g/kg) exhibited significant (P shift from monocots with higher vulnerability to soil pathogens in the ND fertile soil to dicots with higher dependence on nutritional mutualists in the degraded infertile soil. The emerging irreversible eco-evolutionary in PSF after degradation might cause a predicament for the restoration of degraded grassland.

关键词： plant-soil feedback plant function groups degradation alpine grassland Tibetan Plateau LITTER DECOMPOSITION COMMUNITY TRAITS DIVERSITY COMPETITION DEPENDENCE ECOSYSTEM DYNAMICS DRIVERS CARBON

Pipeline Embolization Device for intracranial aneurysms presenting with mass effect:a large Chinese cohort

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Stroke & Vascular Neurology 2024年第1期9卷 50-58页

作者： Yang Zhao Junlin Lu Hongqi Zhang Tianxiao LI Donglei Song sheng Guan Aisha Maimaitili Yunyan Wang Wenfeng Feng Yang Wang Jieqing Wan Guohua Mao Huaizhang shi Xinjian Yang Jianmin Liu Yuanli Zhao Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurosurgery Peking University International HospitalBeijingChina Department of Neurosurgery West China HospitalSichuan UniversityChengduSichuanChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Interventional Neuroradiology Zhengzhou University People's HospitalZhengzhouHenanChina Department of Neurosurgery Shanghai Donglei Brain HospitalShanghaiChina Department of Interventional Neuroradiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenanChina Department of Neurosurgery The First Affiliated Hospital of Xinjiang Medical UniversityUrumqiXinjiangChina Department of Neurosurgery Qilu Hospital of Shandong University QingdaoJinanShandongChina Department of Neurosurgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdongChina Department of Neurosurgery The First Affiliated Hospital of Nanchang UniversityNanchangJiangxiChina Department of Neurosurgery Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Neurosurgery The Second Affiliated Hospital of Nanchang UniversityNanchangJiangxiChina Department of Neurosurgery The First Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiangChina Department of Neurosurgery Changhai HospitalNaval Medical UniversityShanghaiChina

Background Unruptured intracranial aneurysm treatment aims to reduce the risk of aneurysm rupture and bleeding,relieves symptoms and improve the quality of life for *** study aimed to assess the safety and efficacy of Pipeline Embolization Device(PED,Covidien/Medtronic,Irvine,CA)treatment for intracranial aneurysms presenting with mass effect in real-world *** We selected patients from the PED in China Post-Market Multi-Center Registry Study with mass effect *** study endpoints included postoperative mass effect deterioration and mass effect relief at follow-up(3–36 months).We conducted multivariate analysis to identify factors associated with mass effect *** analyses by aneurysm location,size and form were also *** This study included 218 patients with a mean age of 54.3±11.8 years and a female predominance of 74.0%(162/218).The postoperative mass effect deterioration rate was 9.6%(21/218).During a median follow-up period of 8.4 months,the mass effect relief rate was 71.6%(156/218).Notably,immediate aneurysm occlusion following treatment was significantly associated with mass effect relief(OR 0.392,95%CI,0.170 to 0.907,p=0.029).Subgroup analysis demonstrated that adjunctive coiling contributed to mass effect relief in cavernous aneurysms,while dense embolism impeded symptom relief in aneurysms<10mm and saccular *** Our data confirmed the efficacy of PED in relieving mass *** findings of this study provide support for endovascular treatment to alleviate mass effect in unruptured intracranial *** registration number NCT03831672.

关键词： aneurysm intracranial Irvine

Satellite anomaly detection based on reconstruction discrepancy theory utilizing a new dual-branch reconstruction model

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Science China Technological Sciences 2024年第10期67卷 3294-3307页

作者： ZHAO HaoTian QIU shi LIU Ming CAO XiBin Research Center of Satellite Technology School of AstronauticsHarbin Institute of Technology

To enhance the accuracy of deep learning methods based on reconstruction discrepancy in satellite anomaly detection tasks, this study proposes a dual-branch reconstruction model(DBRM) and designs a comprehensive satellite anomaly detection framework around this model. Firstly, we introduce the temporal-channel mixer(TC-Mixer) module, which mainly comprises a self-attention layer for capturing long-range temporal dependencies in telemetry data, and two types of feed-forward networks(FFN) for extracting complex patterns in the temporal and channel dimension of telemetry data. This design endows the TC-Mixer module with robust capabilities for extracting complicated dependencies in telemetry data. Secondly, with the TC-Mixer module as the main component, we designed the DBRM. This model utilizes a shared latent representation layer, allowing the regeneration branch and forecasting branch of the DBRM to share most of the feature extraction network architecture. This approach significantly enhances the model's regression accuracy while reducing computational complexity. Thirdly, using the DBRM as the core network model, we devised a comprehensive satellite anomaly detection framework. This includes an anomaly criterion that considers the reconstruction discrepancy of both the regeneration and forecasting branches, the peak-over-threshold(POT) method for anomaly thresholding, and the MIC-based feature engineering method, etc. Finally, we conducted comparative experiments with several SOTA anomaly detection algorithms on two public and one private satellite anomaly detection datasets. The experimental results validate the effectiveness and superiority of our proposed method.

关键词： anomaly detection reconstruction discrepancy dual-branch reconstruction model (DBRM) satellite telemetry data time series

Cyber-Syndrome:Concept,Theoretical Characterization,and Control Mechanism

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Tsinghua Science and Technology 2024年第3期29卷 721-735页

作者： Feifei shi Huansheng Ning Liming Chen Sahraoui Dhelim School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Faculty of Computing Ulster UniversityNewtownabbeyBT370QBUK School of Computer Science University College DublinDublinD04 V1W8Ireland

The prevalence of social media and mobile computing has led to intensive user engagement in the emergent Cyber-Physical-Social-Thinking(CPST)***,the easy access,the lack of governance,and excessive use has generated a raft of new behaviors within CPST,which affects users’physical,social,and mental *** this paper,we conceive the Cyber-Syndrome concept to denote the collection of cyber disorders due to excessive or problematic Cyberspace interactions based on CPST *** we characterize the Cyber-Syndrome concept in terms of Maslow’s theory of Needs,from which we establish an in-depth theoretical understanding of Cyber-Syndrome from its etiology,formation,symptoms,and ***,we propose an entropy-based Cyber-Syndrome control mechanism for its computation and *** goal of this study is to give new insights into this rising phenomenon and offer guidance for further research and development.

关键词： Cyber-Syndrome cyber-physical systems Cyber-Physical-Social-Thinking(CPST)space Maslow’shierarchy of Needs entropy

Kinetic scale magnetic holes in the terrestrial magnetosheath:A review

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Science China Earth Sciences 2024年第9期67卷 2739-2771页

作者： Quanqi shi Shutao YAO Maria HAMRIN Ji LIU Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Department of Physics UmeåUniversityUmeå90746Sweden Department of Physics University of AlbertaEdmonton T6K 2P6Canada

Magnetic holes at the ion-to-electron kinetic scale(KSMHs)are one of the extremely small intermittent structures generated in turbulent magnetized *** recent years,the explorations of KSMHs have made substantial strides,driven by the ultra-high-precision observational data gathered from the Magnetospheric Multiscale(MMS)*** review paper summarizes the up-to-date characteristics of the KSMHs observed in Earth’s turbulent magnetosheath,as well as their potential impacts on space *** review starts by introducing the fundamental properties of the KSMHs,including observational features,particle behaviors,scales,geometries,and distributions in terrestrial *** have discovered that KSMHs display a quasi-circular electron vortex-like structure attributed to electron diamagnetic *** electrons exhibit noticeable non-gyrotropy and undergo *** occurrence rate of KSMH in the Earth’s magnetosheath is significantly greater than in the solar wind and magnetotail,suggesting the turbulent magnetosheath is a primary source ***,KSMHs have also been generated in turbulence simulations and successfully reproduced by the kinetic equilibrium ***,KSMHs have demonstrated their ability to accelerate electrons by a novel non-adiabatic electron acceleration mechanism,serve as an additional avenue for energy dissipation during magnetic reconnection,and generate diverse wave phenomena,including whistler waves,electrostatic solitary waves,and electron cyclotron waves in space *** results highlight the magnetic hole’s impact such as wave-particle interaction,energy cascade/dissipation,and particle acceleration/heating in space *** end this paper by summarizing these discoveries,discussing the generation mechanism,similar structures,and observations in the Earth’s magnetotail and solar wind,and presenting a future extension perspective in this active field.

关键词： Magnetic hole Magnetic dip/cavity Electron vortex Magnetosheath Turbulence Coherent structure Mirror mode Kinetic scale Electron acceleration Whistler

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Imaging of human parafoveal area with large field of view in adaptive optics line scanning ophthalmoscope

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Journal of Innovative Optical Health Sciences 2024年第6期17卷 41-51页

作者： Wen Kong Yiwei Chen Guohua shi Yi He Department of Biomedical Engineering University of Science and Technology of ChinaHefei 230041P.R.China Jiangsu Key Laboratory of Medical Optics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of SciencesSuzhou 215163P.R.China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghai 200031P.R.China Key Laboratory of Myopia of State Health Ministry and Key Laboratory of Visual Impairment and Restoration of ShanghaiShanghai 200003P.R.China

The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological *** current adaptive optics scanning laser ophthalmoscope(AOSLO)provides an excellent tool to acquire accurate and detailed information about the parafoveal area with cellular ***,limited by the scanning speed of two-dimensional scanning,thefield of view(FOV)in the AOSLO system was usually less than or equal to 2,and the stitching for the parafoveal area required dozens of images,which was time-consuming and ***,almost half of patients are unable to obtain stitched images because of their *** solve this problem,we integrate AO technology with the line-scan imaging method to build an adaptive optics line scanning ophthalmoscope(AOLSO)system with a larger *** the AOLSO,afocal spherical mirrors in pairs are nonplanar arranged and the distance and angle between optical elements are optimized to minimize the aberrations,two cylinder lenses are orthogonally placed before the imaging sensor to stretch the point spread function(PSF)for su±ciently digitizing light *** human retinal images show the whole parafoveal area with 55FOV,60 Hz frame rate and cellular *** advantage of the 5FOV of the AOLSO,only 9 frames of the retina are captured with several minutes to stitch a montage image with an FOV of 99,in which photoreceptor counting is performed within approximately 5*** AOLSO system not only provides cellular resolution but also has the capability to capture the parafoveal region in a single frame,which offers great potential for noninvasive studying of the parafoveal area.

关键词： Adaptive optics line scanning retinal imaging system parafoveal capillary vasculature.