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Research in Astronomy and Astrophysics 2024年第6期24卷 1-6页

作者： wei-nan wang Jin-Song Ping Ming-Yuan wang Wen-Zhao Zhang Han-Lin Ye Xing-wei Han Song-Feng Kou Changchun Observatory National Astronomical ObservatoriesChinese Academy of SciencesChangchun 130117China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Astronomy Department Beijing Normal UniversityBeijing 100875China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China nanjing Institute of Astronomical Optics and Technology Chinese Academy of SciencesNanjing 210042China

Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes *** study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the *** obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the *** findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria *** the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the *** study may serve as a new diagnostic tool for the Moon.

关键词： techniques:photometric polarization methods:observational Moon

Fluorescent carbon dots synthesized in solid phase and air for application in LEDs

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nano Research 2024年第9期17卷 8495-8503页

作者： wei-Jie Zheng Zhao-nan Sun Yi-Ming wang Huan-Ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Carbon dots(CDs)have been widely adopted as optical materials because of their excellent luminescent ***,most of the reported synthetic methods are conducted in solvents,especially hydrothermal/solvothermal reactions,leading to intractable problems such as toxic and flammable solvents,complex and inseparable by-products,and dangerously high pressures and ***-phase synthesis of CDs in air is an effective solution to overcome the above issues,but solid reactions always result in uncontrolled growth and agglomeration of *** this study,some inorganic salts are selected as catalysts for synthesizing CDs in solid states and air,which also play as dispersants to hinder CDs *** the meantime,some aromatic derivatives containing hydroxyl and amino groups are chosen as carbon sources,ground with the optimized catalyst,and then heated together in *** production yields are affected by the reaction time and reactant ratio,while the graphitization degrees of the CDs are determined by the reaction *** IG/ID value of their Raman spectra increases from 0.59 to 0.85,and the particle size decreases from 2.5 to 1.4 nm when the synthesis temperature is increased from 200 to 280℃.The as-prepared CDs show emission peaks ranging from 366 to 606 nm,with the photoluminescence(PL)quantum yield up to 53%.Their emission color variation mainly results from different carbon sources,which can be ascribed to the differences in the element composition,functional groups,and graphitic nitrogen content of these *** dispersing CDs of different concentrations into polyvinyl alcohol(PVA)and combining them with blue LEDs,cold,standard,and warm white light emitting devices(WLEDs)are prepared,with a color rendering index(CRI)up to *** the as-prepared CDs have antioxidant ability at high temperature,the as-prepared WLEDs have long lifespans,remaining the effective white luminescence after 72 h continuous work.

关键词： carbon dot solid-phase synthesis white LED photoluminescence inorganic salt catalysis

QoS Routing Optimization Based on Deep Reinforcement Learning in SDN

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Computers, Materials & Continua 2024年第5期79卷 3007-3021页

作者： Yu Song Xusheng Qian nan Zhang wei wang Ao Xiong State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China Marketing Service Center State Grid Jiangsu Electric Power Co.Ltd.Nanjing220000China Customer Service Center State Grid Co.Ltd.Nanjing211161China

To enhance the efficiency and expediency of issuing e-licenses within the power sector, we must confront thechallenge of managing the surging demand for data traffic. Within this realm, the network imposes stringentQuality of Service (QoS) requirements, revealing the inadequacies of traditional routing allocation mechanismsin accommodating such extensive data flows. In response to the imperative of handling a substantial influx of datarequests promptly and alleviating the constraints of existing technologies and network congestion, we present anarchitecture forQoS routing optimizationwith in SoftwareDefinedNetwork (SDN), leveraging deep reinforcementlearning. This innovative approach entails the separation of SDN control and transmission functionalities, centralizingcontrol over data forwardingwhile integrating deep reinforcement learning for informed routing decisions. Byfactoring in considerations such as delay, bandwidth, jitter rate, and packet loss rate, we design a reward function toguide theDeepDeterministic PolicyGradient (DDPG) algorithmin learning the optimal routing strategy to furnishsuperior QoS provision. In our empirical investigations, we juxtapose the performance of Deep ReinforcementLearning (DRL) against that of Shortest Path (SP) algorithms in terms of data packet transmission delay. Theexperimental simulation results show that our proposed algorithm has significant efficacy in reducing networkdelay and improving the overall transmission efficiency, which is superior to the traditional methods.

关键词： Deep reinforcement learning SDN route optimization QoS

Recent progress on rapid diagnosis of COVID-19 by point-of-care testing platforms

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Chinese Chemical Letters 2024年第3期35卷 66-75页

作者： Ya-nan Tang Dingding Jiang Xuejun wang Yunqi Liu Dacheng wei State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China Institute of Molecular Materials and Devices Fudan UniversityShanghai 200433China

The outbreak of COVID-19 has drawn great attention around the ***-CoV-2 is a highly infectious virus with occult transmission by many mutations and a long incubation *** particular,the emergence of asymptomatic infections has made the epidemic even more ***,early diagnosis and timely management of suspected cases are essential measures to control the spread of the *** simple,portable,and accurate diagnostic techniques for SARS-CoV-2 is the key to epidemic *** advantages of point-of-care testing technology make it play an increasingly important role in viral detection and *** review summarizes the point-of-care testing platforms developed by nucleic acid detection,immunological detection,and nanomaterial-based biosensors ***,this paper provides a prospect for designing future highly accurate,cheap,and convenient SARS-CoV-2 diagnostic technology.

关键词： COVID-19 Point-of-care testing platforms Nucleic acid detection Asymptomatic infection Biosensors

Single-step-etched ultra-compact metamaterial grating coupler enabled by a hierarchical inverse design approach

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 119-126页

作者： Qiao wang Ruiqi Luo nan Liu Maojing Hou Bo Xiong Guandong Liu wei Ma Intelligent Network Research Institute Zhejiang LabHangzhou 311100China State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic EngineeringZhejiang UniversityHangzhou 310027China

With the concept of metamaterials introduced into integrated photonics,subwavelength structures have gained popularity for their ability to create devices with ultra-compact size,high performance,and versatile ***,traditional metamaterial design methods are usually based on empirical templates and physical approximations,lacking the ability to design free-form metamaterial structures and optimize entire devices *** this work,we propose a hierarchical inverse design approach that combines a conventional effective refractive index based metamaterial structures design with a follow-up global topology *** empirical metamaterial grating coupler design based on effective refractive index engineering faces inaccurate index extraction and insufficient approximation of wavevector matching conditions,which deteriorates coupling efficiency,especially for fully-etched devices with the decreased tapering ***,a subsequent overall topology optimization step can well compensate for the negative effect of the shrinking device footprint to increase the efficiency of the metamaterial grating *** demonstrate a 23μm×10μm ultra-compact metamaterial grating coupler with single-stepetched to couple light between a fiber and a 500 nm single-mode silicon waveguide in the *** measurement shows an insertion loss of 3.17 dB and a 3 dB bandwidth of 77 nm,making it the smallest footprint device ever reported.

关键词： waveguide hierarchical inverse

Understanding the cooperative effects in the catalysis of homodimeric fluoroacetate dehalogenase

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Science China Chemistry 2024年第7期67卷 2382-2391页

作者： Ke-wei Chen Jia-nan Chen Jun Zhang Chao wang Tian-Yu Sun Yun-Dong Wu Key Laboratory of Computational Chemistry and Drug Design State Key Laboratory of Chemical OncogenomicSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Changping Laboratory Beijing 102200China

Fluoroacetate dehalogenases(FAcD),a homodimeric enzyme,catalyzes the conversion of fluoroacetic acid to glycolic acid(GoA).It has been proved that the enzyme has a half-of-the-site ***,its catalytic(C)subunit converts the first substrate to a covalent intermediate;then,the non-catalytic(NC)subunit binds a second substrate and promotes the conversion of the intermediate in the C subunit into the final *** the release of the product,the C subunit becomes the NC subunit,and the previous NC subunit becomes the C *** elucidate the detailed mechanism behind this cooperative catalysis,we have conducted microsecond-scale MD simulations along the reaction *** simulations indicate that the substrate in the NC subunit induces W185 and Y141 adopting an open conformation in the C *** opening of W185(C)facilitates the entry of catalytic water,enhancing the catalytic activity for product formation,while the opening of Y141(C)creates an unfavorable environment for product binding,promoting its *** interaction network analysis reveals that the substrate in the NC subunit can induce conformational changes through a conserved water chain at the interface.

关键词： enzyme catalysis molecular dynamics cooperative effect pre-reaction state

STING mediates microglial pyroptosis via interaction with NLRP3 in cerebral ischaemic stroke

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Stroke & Vascular Neurology 2024年第2期9卷 153-164页

作者： Wenyu Li nan Shen Lingqi Kong Hongmei Huang Xinyue wang Yan Zhang Guoping wang Pengfei Xu wei Hu Department of Neurology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhuiChina

background Ischaemia-evoked neuroinflammation is a critical pathogenic event following ischaemic *** D(GSDMD)-associated pyroptosis represents a type of inflammation-associated programmed cell death,which can exacerbate neuroinflammatory responses and brain *** of interferon genes(STING)was recently described as a vital innate immune adaptor protein associated with ***,the regulatory effects of STING on microglial pyroptosis post-stroke have not been well *** STING-knockout and wild-type(WT)mice were subjected to middle cerebral artery occlusion(MCAO).STING small interfering RNA(siRNA)was transfected into BV2 cells before oxygen-glucose deprivation/reoxygenation(OGD/R).STING-overexpressing adeno-associated virus(AAV)and NOD-like receptor family pyrin domain containing 3(NLRP3)siRNA were administered by stereotaxic injection.2,3,5-Triphenyl tetrazolium chloride(TTC)staining,TdT-mediated dUTP nick end labeling(TUNEL)staining,Fluoro-Jade C(FJC)staining,neurobehavioural tests,immunohistochemistry,cytokine antibody array assay,transmission electron microscopy,immunoblot,Enzyme-linked immunosorbent assay(ELISA)and quantitative real-time polymerase chain reaction(qRT-PCR)were carried ***-immunoprecipitation assays were used to investigate the interplay between STING and *** STING expression was increased after MCAO and mainly detected on *** deletion alleviated brain infarction,neuronal damage and neurobehavioural impairment in mice subjected to *** knockout suppressed microglial activation and the secretion of inflammatory chemokines,accompanied by mitigation of microglial *** upregulation of microglial STING by AAV-F4/80-STING aggravated brain injury and microglial ***,co-immunoprecipitation showed that STING bound to NLRP3 in *** of NLRP3 siRNA reversed AAV-F4/80-STING-induced deterioration of microglial pyropt

关键词： NLRP3 cerebral inflammation

N-acetylcysteine ameliorates erectile dysfunction in rats with hyperlipidemia by inhibiting oxidative stress and corpus cavernosum smooth muscle cells phenotypic modulation

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Asian Journal of Andrology 2024年第1期26卷 99-106页

作者： wei Ding Jun-Hong Fan Li-Ren Zhong nan-Xiong wang Lu-Hao Liu Hai-Bo Zhang Li wang Ming-Qiang wang Bing-Lin He An-Yang wei Department of Urology The First Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang 550002China Department of Urology Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhou 510000China Department of Urology Nanfang HospitalSouthern Medical UniversityGuangzhou 510000China Department of Urology Shenzhen Immigration Inspection General Station HospitalShenzhen 518000China Department of Organ Transplantation The Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510000China Department of Endocrinology The First Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang 550002China

Hyperlipidemia is a major risk factor for erectile dysfunction(ED).Oxidative stress and phenotypic modulation of corpus cavernosum smooth muscle cells(CcSMCs)are the key pathological factors of ED.N-acetylcysteine(NAC)can inhibit oxidative stress;however,whether NAc can alleviate pathological variations in the corpus cavernosum and promote erectile function recovery in hyperlipidemic rats remains unclear.A hyperlipidemia model was established using 27 eight-week-old male Sprague-Dawley(SD)rats fed a high-fat and high-cholesterol diet(hyperlipidemic rats,HR).In addition,9 male SD rats were fed a normal diet to serve as controls(NC).HR rats were divided into three groups:HR,HR+normal saline(NS),and HR+NAC(n=9 for each group;NS or NAc intraperitoneal injections were administered daily for 16 weeks).Subsequently,the lipid profiles,erectile function,oxidative stress,phenotypic modulation markers of ccsMCs,and tissue histology were *** experimental results revealed that erectile function was significantly impaired in the HR and HR+NS groups,but enhanced in the HR+NAC *** lipid levels,over-activated oxidative stress,and multi-organ lesions observed in the HR and HR+NS groups were improved in the HR+NAC ***,the HR group showed significant phenotypic modulation of CCSMCs,which was also inhibited by NAC *** report focuses on the therapeutic effect of NAc in restoring erectile function using a hyperlipidemic rat model by preventing CcSMC phenotypic modulationand attenuating oxidativestress.

关键词： erectile dysfunction hyperlipidemia N-acetylcysteine oxidative stress henotypic modulation

{1012}twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2Zn alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1529-1539页

作者： Bin-Jiang Lv Sen wang Fu-Hao Gao Ning Cui Yi-nan Li Tie-wei Xu Feng Guo School of Mechanical and Automotive Engineering Qingdao University of Technology266520China Key Lab of industrial Fluid Energy Conservation and Pollution Control Qingdao University of Technology266520China

This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal *** results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°boundaries formed due to twin–twin intersections under different strain *** twin variants with 60°boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°boundaries transformed into new grains via dynamic recrystallization.

关键词： Mg alloy Twin-twin intersection Lattice rotation Dynamic recrystallization

Structural transformation from Waugh-type to Keggin-type polyoxomolybdate-based crystalline material for photo/electrocatalysis

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Rare Metals 2024年第5期43卷 2241-2250页

作者： Pei-Sen wang Zi-Tong wang Ya-Ya Tan Peng Chen Xue-Cheng Zhang Lu-nan Zhang Yong-Ge wei Lu-Bin Ni School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing100191China

An inorganicDorganic hybrid crystalline material(SiMo_(12)O_(40))[Cu(2,2'-bipy)_(2)]_(2)·2H_(2)O(Complex 1,2,2'-bipy=2,2'-bipyridine)was synthesized for the first time by using 2,2'-bipy and transition metal copper to convert Waugh-type polyoxometalate[MnMo_(9)O_(3)_(2)]_(6-)into a Keggin polyoxometalate structure[SiMo_(12)O_(40)]^(4-)under hydrothermal conditions in glass *** crystal tests and a series of characterizations were carried out on Complex *** structure of Complex 1 is composed of[SiMo_(12)O_(40)]^(4-)and[Cu^(Ⅱ)(2,2'-bipy)_(2)]^(2+).The five-coordinated Cu is connected to two 2,2'-bipy through CuDN bonds,forming an approximately square ***,Complex 1 exhibited good photocatalytic performance for methylene blue degradation and electrocatalytic nitrite reduction properties simultaneously.

关键词： Polyoxometalates Inorganic-organic hybrid materials Photocatalytic Electrocatalytic