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Genetic pathways in cerebral palsy:a review of the implications for precision diagnosis and understanding disease mechanisms 被引量:1
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作者 Yiran Xu yifei li +2 位作者 Seidu A.Richard Yanyan Sun Changlian Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1499-1508,共10页
Ce rebral palsy is a diagnostic term utilized to describe a group of permanent disorders affecting movement and posture.Patients with cerebral palsy are often only capable of limited activity,resulting from non-progre... Ce rebral palsy is a diagnostic term utilized to describe a group of permanent disorders affecting movement and posture.Patients with cerebral palsy are often only capable of limited activity,resulting from non-progressive disturbances in the fetal or neonatal brain.These disturbances severely impact the child’s daily life and impose a substantial economic burden on the family.Although cerebral palsy encompasses various brain injuries leading to similar clinical outcomes,the unde rstanding of its etiological pathways remains incomplete owing to its complexity and heterogeneity.This review aims to summarize the current knowledge on the genetic factors influencing cerebral palsy development.It is now widely acknowledged that genetic mutations and alterations play a pivotal role in cerebral palsy development,which can be further influenced by environmental fa ctors.Des pite continuous research endeavors,the underlying fa ctors contributing to cerebral palsy remain are still elusive.However,significant progress has been made in genetic research that has markedly enhanced our comprehension of the genetic factors underlying cerebral palsy development.Moreove r,these genetic factors have been categorized based on the identified gene mutations in patients through clinical genotyping,including thrombosis,angiogenesis,mitochondrial and oxidative phosphorylation function,neuronal migration,and cellular autophagy.Furthermore,exploring targeted genotypes holds potential for precision treatment.In conclusion,advancements in genetic research have substantially improved our understanding of the genetic causes underlying cerebral palsy.These breakthroughs have the potential to pave the way for new treatments and therapies,consequently shaping the future of cerebral palsy research and its clinical management.The investigation of cerebral palsy genetics holds the potential to significantly advance treatments and management strategies.By elucidating the underlying cellular mechanisms,we can develop to rgeted interventions to optimize outcomes.A continued collaboration between researchers and clinicians is imperative to comprehensively unravel the intricate genetic etiology of cerebral palsy. 展开更多
关键词 cerebral palsy environmental factors ETIOLOGY genetic factors genetic mutation movement disorder spastic diplegia
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Ginsenoside Rb1 induces hepatic stellate cell ferroptosis to alleviate liver fibrosis via the BECN1/SLC7A11 axis 被引量:1
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作者 lifan lin Xinmiao li +3 位作者 yifei li Zhichao Lang Yeping li Jianjian Zheng 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第5期744-757,共14页
Liver fibrosis is primarily driven by the activation of hepatic stellate cells(HSCs),a process associated with ferroptosis.Ginsenoside Rb1(GRb1),a major active component extracted from Panax ginseng,inhibits HSC activ... Liver fibrosis is primarily driven by the activation of hepatic stellate cells(HSCs),a process associated with ferroptosis.Ginsenoside Rb1(GRb1),a major active component extracted from Panax ginseng,inhibits HSC activation.However,the potential role of GRb1 in mediating HSC ferroptosis remains unclear.This study examined the effect of GRb1 on liver fibrosis both in vivo and in vitro,using CCl4-induced liver fibrosis mouse model and primary HSCs,LX-2 cells.The findings revealed that GRb1 effectively inactivated HSCs in vitro,reducing alpha-smooth muscle actin(a-SMA)and type I collagen(Col1A1)levels.Moreover,GRb1 significantly alleviated CCl4-induced liver fibrosis in vivo.From a mechanistic standpoint,the ferroptosis pathway appeared to be central to the antifibrotic effects of GRb1.Specifically,GRb1 promoted HSC ferroptosis both in vivo and in vitro,characterized by increased glutathione depletion,malondialdehyde production,iron overload,and accumulation of reactive oxygen species(ROS).Intriguingly,GRb1 increased Beclin 1(BECN1)levels and decreased the System Xc-key subunit SLC7A11.Further experiments showed that BECN1 silencing inhibited GRb1-induced effects on HSC ferroptosis and mitigated the reduction of SLC7A11 caused by GRb1.Moreover,BECN1 could directly interact with SLC7A11,initiating HSC ferroptosis.In conclusion,the suppression of BECN1 counteracted the effects of GRb1 on HSC inactivation both in vivo and in vitro.Overall,this study highlights the novel role of GRb1 in inducing HSC ferroptosis and promoting HSC inactivation,at least partly through its modulation of BECN1 and SLC7A11. 展开更多
关键词 Ginsenoside Rb1 Ferroptosis Liver fibrosis Hepatic stellate cells
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Effects of gallium surfactant on AlN thin films by microwave plasma chemical vapor deposition
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作者 Lu Wang Xulei Qin +8 位作者 li Zhang Kun Xu Feng Yang Shaoqian Lu yifei li Bosen liu Guohao Yu Zhongming Zeng Baoshun Zhang 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期53-60,共8页
In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly impro... In this work, AlN films were grown using gallium (Ga) as surfactant on 4° off-axis 4H-SiC substrates via microwave plasma chemical vapor deposition (MPCVD). We have found that AlN growth rate can be greatly improved due to the catalytic effect of trimethyl-gallium (TMGa), but AlN crystal structure and composition are not affected. When the proportion of TMGa in gas phase was low, crystal quality of AlN can be improved and three-dimensional growth mode of AlN was enhanced with the increase of Ga source. When the proportion of TMGa in gas phase was high, two-dimensional growth mode of AlN was presented, with the increase of Ga source results in the deterioration of AlN crystal quality. Finally, employing a two-step growth approach, involving the initial growth of Ga-free AlN nucleation layer followed by Ga-assisted AlN growth, high quality of AlN film with flat surface was obtained and the full width at half maximum (FWHM) values of 415 nm AlN (002) and (102) planes were 465 and 597 arcsec. 展开更多
关键词 AlN thin film MPCVD gallium surfactant nucleation layer LASER
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A Novel Bi-Level VSC-DC Transmission Expansion PlanningMethod of VSC-DC for Power System Flexibility and Stability Enhancement
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作者 Weigang Jin Lei Chen +3 位作者 Shencong Zheng Yuqi Jiang yifei li Hongkun Chen 《Energy Engineering》 EI 2024年第11期3161-3179,共19页
Investigating flexibility and stability boosting transmission expansion planning(TEP)methods can increase the renewable energy(RE)consumption of the power systems.In this study,we propose a bi-level TEP method for vol... Investigating flexibility and stability boosting transmission expansion planning(TEP)methods can increase the renewable energy(RE)consumption of the power systems.In this study,we propose a bi-level TEP method for voltage-source-converter-based direct current(VSC-DC),focusing on flexibility and stability enhancement.First,we established the TEP framework of VSC-DC,by introducing the evaluation indices to quantify the power system flexibility and stability.Subsequently,we propose a bi-level VSC-DC TEP model:the upper-level model acquires the optimal VSC-DC planning scheme by using the improved moth flame optimization(IMFO)algorithm,and the lower-level model evaluates the flexibility through time-series production simulation.Finally,we applied the proposedVSC-DC TEPmethod to the modified IEEE-24 and IEEE-39 test systems,and obtained the optimalVSCDC planning schemes.The results verified that the proposed method can achieve excellent RE curtailment with high flexibility and stability.Furthermore,the well-designed IMFO algorithm outperformed the traditional particle swarm optimization(PSO)and moth flame optimization(MFO)algorithms,confirming the effectiveness of the proposed approach. 展开更多
关键词 VSC-DC transmission expansion planning renewable energy consumption line delivery flexibility short-circuit ratio improved moth flame optimization algorithm
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Online Consensus Control of Nonlinear Affine Systems From Disturbed Data
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作者 yifei li Wenjie liu +3 位作者 Jian Sun Chen Chen Jia Zhang Gang Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期551-553,共3页
Dear Editor,In this letter, we introduce a novel online distributed data-driven robust control approach for learning controllers of unknown nonlinear multi-agent systems(MASs) using state-dependent representations.
关键词 AGENT ONLINE ONLINE
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The effect of anode axial position on the performance of a miniaturized cylindrical Hall thruster with a cusp-type magnetic field
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作者 Yuanyuan GAO Weizong WANG +2 位作者 yifei li Shuwen XUE Guobiao CAI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第7期15-22,共8页
A 200 W cylindrical Hall thruster with a cusp-type magnetic field was proposed, manifesting convergent plume and high specific impulse. In this paper, a series of ring-shaped anodes are designed and the influence of a... A 200 W cylindrical Hall thruster with a cusp-type magnetic field was proposed, manifesting convergent plume and high specific impulse. In this paper, a series of ring-shaped anodes are designed and the influence of anode axial position on the performance of CHT with a cusp-type magnetic field is studied. The experimental results indicate that the thruster keeps stable operation at the condition of 140–270 W discharge power. When the anode moves axially towards the upstream cusp field, the thrust enhances from 6.5 mN to 7.6 mN and specific impulse enhances from 1658 s to 1939 s significantly. These improvements of thruster performance should be attributed to the enhancement of current utilization, propellant utilization and acceleration efficiency. According to the analyses on the discharge characteristics, it is revealed that as the anode moves upstream, the electron transport path could be extended, the magnetic field in this extended path could impede electron cross-field transport and facilitate the ionization intensity, yielding to the enhancement of current utilization and propellant utilization efficiency.Moreover, along with this enhancement of upstream ionization at the given anode flow rate, the main ionization region is thought to move upstream and then separate more apparently from the acceleration region, which has been demonstrated by the narrowing of ion energy distribution function shape. This change in acceleration region could decrease the ion energy loss and enhance acceleration efficiency. This work is beneficial for optimizing the electrode structure of thruster and recognize the ionization and acceleration process under the cusp magnetic field. 展开更多
关键词 PERFORMANCE ionization characteristics acceleration characteristics cylindrical Hall thruster anode axial position
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Collimated gamma rays from laser wakefield accelerated electrons
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作者 Minghua li liming Chen +8 位作者 Dazhang li Kai Huang yifei li Yong Ma Wenchao Yan Mengze Tao Junhao Tan Zhengming Sheng Jie Zhang 《Matter and Radiation at Extremes》 SCIE EI CAS 2018年第4期188-196,共9页
Betatron radiation from laser wakefield accelerated electrons and X-rays scattered off a counter-propagating relativistic electron bunch arecollimated and hold the potential to extend the energy range to hard X-ray or... Betatron radiation from laser wakefield accelerated electrons and X-rays scattered off a counter-propagating relativistic electron bunch arecollimated and hold the potential to extend the energy range to hard X-ray or gamma ray band. The peak brightness of these incoherent radiations could reach the level of the brightest synchrotron light sources in the world due to their femtosecond pulse duration and source sizedown to a few micrometers. In this article, the principle and properties of these radiation sources are briefly reviewed and compared. Then wepresent our recent progress in betatron radiation enhancement in the perspective of both photon energy and photon number. The enhancement istriggered by using a clustering gas target, arousing a second injection of a fiercely oscillating electron bunch with large charge or stimulating aresonantly enhanced oscillation of the ionization injected electrons. By adopting these methods, bright photon source with energy over 100 keVis generated which would greatly impact applications such as nuclear physics, diagnostic radiology, laboratory astrophysics and high-energydensity science. 展开更多
关键词 Laser wakefield accelerator Gamma ray Hard X-ray Betatron radiation ENHANCEMENT
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Resource Allocation for Uplink CSI Sensing Report in Multi-User WLAN Sensing
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作者 yifei li Jilei Yan +2 位作者 Yan Long Xuming Fang Rong He 《Journal of Beijing Institute of Technology》 EI CAS 2022年第5期524-534,共11页
Sensing in wireless local area network(WLAN) gains great interests recently. In this paper we focus on the multi-user WLAN sensing problem under the existing 802.11 standards. Multiple stations perform sensing with th... Sensing in wireless local area network(WLAN) gains great interests recently. In this paper we focus on the multi-user WLAN sensing problem under the existing 802.11 standards. Multiple stations perform sensing with the access point and transmit channel state information(CSI)report simultaneously on the basis of uplink-orthogonal frequency division multiple access(OFDMA). Considering the transmission resource consumed in CSI report and the padding wastage in OFDMA based CSI report, we optimize the CSI simplification and uplink resource unit(RU)allocation jointly, aiming to balance the sensing accuracy and padding wastage performances in WLAN sensing. We propose the minimize padding maximize efficiency(MPME) algorithm to solve the problem and evaluate the performance of the proposed algorithm through extensive simulations. 展开更多
关键词 wireless local area network(WLAN)sensing channel state information(CSI)simplification padding wastage resource allocation
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Research on Equivalent Modeling Method of AC-DC Power Networks Integrating with Renewable Energy Generation
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作者 Weigang Jin Lei Chen +3 位作者 yifei li Shencong Zheng Yuqi Jiang Hongkun Chen 《Energy Engineering》 EI 2023年第11期2469-2487,共19页
Along with the increasing integration of renewable energy generation in AC-DC power networks,investigating the dynamic behaviors of this complex system with a proper equivalent model is significant.This paper presents... Along with the increasing integration of renewable energy generation in AC-DC power networks,investigating the dynamic behaviors of this complex system with a proper equivalent model is significant.This paper presents an equivalent modeling method for the AC-DC power networks with doubly-fed induction generator(DFIG)based wind farms to decrease the simulation scale and computational burden.For the AC-DC power networks,the equivalent modeling strategy in accordance with the physical structure simplification is stated.Regarding the DFIG-based wind farms,the equivalent modeling based on the sequential identification of multi-machine parameters using the improved chaotic cuckoo search algorithm(ICCSA)is conducted.In light of the MATLAB simulation platform,a two-zone four-DC interconnected power grid with wind farms is built to check the efficacy of the proposed equivalentmodelingmethod.Fromthe simulation analyses and comparative validation in different algorithms and cases,the proposed method can precisely reflect the steady and dynamic performance of the demonstrated system under N-1 and N-2 fault scenarios,and it can efficiently achieve the parameter identification of the wind farms and fulfill the equivalent modeling.Consequently,the proposed approach’s effectiveness and suitability are confirmed. 展开更多
关键词 Equivalent modeling AC-DC power networks renewable energy generation wind farm improved chaotic cuckoo search algorithm
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A Cross-View Model for Tourism Demand Forecasting with Artificial Intelligence Method
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作者 Siming Han Yanhui Guo +2 位作者 Han Cao Qian Feng yifei li 《国际计算机前沿大会会议论文集》 2017年第1期144-146,共3页
Forecasting always plays a vital role in modern economic and industrial fields,and tourism demand forecasting is an important part of intelligent tourism.This paper proposes a simple method for data modeling and a com... Forecasting always plays a vital role in modern economic and industrial fields,and tourism demand forecasting is an important part of intelligent tourism.This paper proposes a simple method for data modeling and a combined cross-view model,which is easy to implement but very effective.The method presented in this paper is commonly used for BPNN and SVR algorithms.A real tourism data set of Small Wild Goose Pagoda is used to verify the feasibility of the proposed method,with the analysis of the impact of year,season,and week on tourism demand forecasting.Comparative experiments suggest that the proposed model shows better accuracy than contrast methods. 展开更多
关键词 CROSS-VIEW BPNN SVR ARIMA
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Self-confocal NIR-II fluorescence microscopy for multifunctional in vivo imaging
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作者 Jing Zhou Tianxiang Wu +5 位作者 Runze Chen liang Zhu Hequn Zhang yifei li liying Chen Jun Qian 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期105-119,共15页
Fluorescence imaging in the second near-infrared window(NIR-II,900–1880 nm)with less scattering background in biological tissues has been combined with the confocal microscopic system for achieving deep in vivo imagi... Fluorescence imaging in the second near-infrared window(NIR-II,900–1880 nm)with less scattering background in biological tissues has been combined with the confocal microscopic system for achieving deep in vivo imaging with high spatial resolution.However,the traditional NIR-IIfluorescence confocal microscope with separate excitation focus and detection pinhole makes it possess low confocal e±ciency,as well as di±cultly to adjust.Two types of upgraded NIR-IIfluorescence confocal microscopes,sharing the same pinhole by excitation and emission focus,leading to higher confocal e±ciency,are built in this work.One type is-ber-pinhole-based confocal microscope applicable to CW laser excitation.It is constructed forfluorescence intensity imaging with large depth,high stabilization and low cost,which could replace multiphotonfluorescence microscopy in some applications(e.g.,cerebrovascular and hepatocellular imaging).The other type is air-pinhole-based confocal microscope applicable to femtosecond(fs)laser excitation.It can be employed not only for NIR-IIfluorescence intensity imaging,but also for multi-channelfluorescence lifetime imaging to recognize different structures with similarfluorescence spectrum.Moreover,it can be facilely combined with multiphotonfluorescence microscopy.A single fs pulsed laser is utilized to achieve up-conversion(visible multiphotonfluorescence)and down-conversion(NIR-II one-photonfluorescence)excitation simultaneously,extending imaging spectral channels,and thus facilitates multi-structure and multi-functional observation. 展开更多
关键词 Self-confocal fiber-pinhole air-pinhole multi-channe fluorescence lifetime imaging multi-color imaging
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Diameter-dependent ultra-high thermoelectric performance of ZnO nanowires
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作者 聂祎楠 唐桂华 +2 位作者 李一斐 张敏 赵欣 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期86-94,共9页
Zinc oxide(ZnO)shows great potential in electronics,but its large intrinsic thermal conductivity limits its thermoelectric applications.In this work,we explore the significant carrier transport capacity and diameter-d... Zinc oxide(ZnO)shows great potential in electronics,but its large intrinsic thermal conductivity limits its thermoelectric applications.In this work,we explore the significant carrier transport capacity and diameter-dependent thermoelectric characteristics of wurtzite-ZnO(0001)nanowires based on first-principles and molecular dynamics simulations.Under the synergistic effect of band degeneracy and weak phonon-electron scattering,P-type(ZnO)_(73) nanowires achieve an ultrahigh power factor above 1500μW·cm^(-1)·K^(-2)over a wide temperature range.The lattice thermal conductivity and carrier transport properties of ZnO nanowires exhibit a strong diameter size dependence.When the ZnO nanowire diameter exceeds 12.72A,the carrier transport properties increase significantly,while the thermal conductivity shows a slight increase with the diameter size,resulting in a ZT value of up to 6.4 at 700 K for P-type(ZnO)_(73).For the first time,the size effect is also illustrated by introducing two geometrical configurations of the ZnO nanowires.This work theoretically depicts the size optimization strategy for the thermoelectric conversion of ZnO nanowires. 展开更多
关键词 ZnO nanowire size effect thermoelectric performance deformation potential theory
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A five-parameter constitutive model for hysteresis shearing and energy dissipation of rock joints 被引量:3
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作者 Yikun li Tongbin Zhao +1 位作者 yifei li Yang Chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第4期737-746,共10页
Rock joints exhibit hysteresis shearing behavior and produce energy dissipation under shear cyclic loads,which however cannot be accurately depicted by existing constitutive models. This paper establishes a constituti... Rock joints exhibit hysteresis shearing behavior and produce energy dissipation under shear cyclic loads,which however cannot be accurately depicted by existing constitutive models. This paper establishes a constitutive model for hysteresis shearing and associated energy dissipation of rock joints. Analytical expressions of the model during cyclic shearing processes are derived. Derivation of the model indicates no energy dissipation in the elastic stage. When the shear load exceeds elastic boundary, nonlinear energy dissipation takes place. Validations with experiments show that the proposed model provides good conformities with direct shear curves and hysteresis loops, and can predict the energy dissipation characteristics of rock joints under different working conditions. Compared to the constitutive models using Weibull's distribution, the proposed one is smooth at the elastic boundary and can accurately capture the maximum shear stress. Unlike the existing incremental-type models, the proposed one provides clear and direct analytical expressions for both shear stress and energy dissipation during the whole displacement domain, which is more convenient in application. 展开更多
关键词 Iwan model Rock joint Cyclic shear HYSTERESIS Energy dissipation
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Rare earth alloy nanomaterials in electrocatalysis 被引量:2
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作者 yifei li Xilin Yuan +5 位作者 Ping Wang Lulin Tang Miao He Pangen li Jiang li Zhenxing li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期574-594,I0014,共22页
With the rapid development of society and economy, the excessive consumption of fossil energy has led to the global energy and environment crisis. In order to explore the sustainable development of new energy, researc... With the rapid development of society and economy, the excessive consumption of fossil energy has led to the global energy and environment crisis. In order to explore the sustainable development of new energy, research based on electrocatalysis has attracted extensive attention in the academic circle. The main challenge in this field is to develop nano-catalysts with excellent electrocatalytic activity and selectivity for target products. The state of the active site in catalyst plays a decisive role in the activity and selectivity of the reaction. In order to design efficient and excellent catalysts, it is an effective means to adjust the electronic structure of catalysts. Electronic effects are also called ligand effects. By alloying with rare earth(RE) elements, electrons can be redistributed between RE elements and transition metal elements, achieving accurate design of the electronic structure of the active site in the alloy. Because of the unique electronic structure of RE, it has been paid attention in the field of catalysis. The outermost shell structure of RE elements is basically the same as that of the lower shell, except that the number of electrons in the 4f orbital is different, but the energy level is similar, so their properties are very similar. When RE elements form compounds, both the f electrons in the outermost shell and the d electrons in the lower outer shell can participate in bonding. In addition, part of the 4f electrons in the third outer shell can also participate in bonding.In order to improve the performance of metal catalysts, alloying provides an effective method to design advanced functional materials. RE alloys can integrate the unique electronic structure and catalytic behavior of RE elements into metal materials, which not only provides an opportunity to adjust the electronic structure and catalytic activity of the active component, but also enhances the structural stability of the alloy and is expected to significantly improve the catalytic performance of the catalyst. From the perspective of electronic and catalytic activity, RE elements have unique electronic configuration and lanthanide shrinkage effect. Alloying with RE elements will make the alloy have more abundant electronic structure, activity, and spatial arrangement, effectively adjusting the reaction kinetics of the electrochemical process of the catalyst. In this paper, the composition,structure, synthesis of RE alloys and their applications in the field of electrocatalysis are summarized, including the hydrogen evolution reaction, the oxygen evolution reaction, the oxygen reduction reaction, the methanol oxidation reaction, the ethanol oxidation reaction, and other catalytic reactions. At the same time, the present challenges of RE alloy electrocatalytic materials are summarized and their future development direction is pointed out. In the field of electrocatalysis, the cost of catalyst is too high and the stability is not strong. Therefore, the testing process should be related to the actual application, and the test method should be standardized, so as to carry forward the field of electrocatalysis. 展开更多
关键词 Rare earth Alloy nanomaterials ELECTROCATALYSIS Preparation methods Hydrogen evolution reaction Oxygen reduction reaction Methanol oxidation reaction Ethanol oxidation reaction
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基于GIS与地表覆盖的城乡划分实证研究——以武汉为例
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作者 李逸霏 詹庆明 《城镇化与集约用地》 2014年第4期63-70,共8页
正确的城乡划分是评估城市化水平的基础,快速城市化导致的城乡交接地区的用地快速变化和混乱程度加剧,造成城乡范围难以界定。本文提出一套可行的城乡实体用地的划分技术方法,并以武汉市为例,利用2010年地表覆盖数据及百万居民点分布数... 正确的城乡划分是评估城市化水平的基础,快速城市化导致的城乡交接地区的用地快速变化和混乱程度加剧,造成城乡范围难以界定。本文提出一套可行的城乡实体用地的划分技术方法,并以武汉市为例,利用2010年地表覆盖数据及百万居民点分布数据进行实体地域的城乡划分。 展开更多
关键词 GIS 城乡划分 城市化
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Ultra-fast x-ray-dynamic experimental subsystem
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作者 liming Chen Xin Lu +1 位作者 Dazhang li yifei li 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第7期44-49,共6页
Ultra-fast x-ray-dynamic experimental subsystem is a facility which can provide femtosecond hard x-ray sources using a femtosecond laser interacting with plasmas. By utilizing these ultra-fast x-rays as a probe, combi... Ultra-fast x-ray-dynamic experimental subsystem is a facility which can provide femtosecond hard x-ray sources using a femtosecond laser interacting with plasmas. By utilizing these ultra-fast x-rays as a probe, combined with a naturally synchronized driver laser as a pump, we can perform dynamic studies on samples with a femtosecond time resolution. This subsystem with a four-dimensional ultra-high spatiotemporal resolution is a powerful tool for studies of the process of photosynthesis, Auger electron effects, lattice vibrations, etc. Compared with conventional x-ray sources based on accelerators, this table-top laser-driven x-ray source has significant advantages in terms of the source size, pulse duration, brightness, flexibility, and economy. It is an effective supplement to the synchrotron light source in the ultrafast detection regime. 展开更多
关键词 ultra-fast x-ray diffraction/absorption time-resolved pump-probe detection ultra-highspatiotemporal-resolution detection
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Anorectal Pharmacodynamics and In Vitro Drug Release of Clerodendrum bungei Steud.Extract Gel
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作者 Shuyan ZHANG yifei li +2 位作者 Qianchen JIAO Chunmei li likou ZOU 《Medicinal Plant》 CAS 2023年第3期61-65,共5页
[Objectives]To determine the optimal preparation technology of Clerodendrum bungei Steud.extract gel by orthogonal test and gel quality test method in General Rule 0114 of Chinese Pharmacopoeia(Volume IV,2020 Edition)... [Objectives]To determine the optimal preparation technology of Clerodendrum bungei Steud.extract gel by orthogonal test and gel quality test method in General Rule 0114 of Chinese Pharmacopoeia(Volume IV,2020 Edition),and to study its anorectal pharmacodynamics and drug release in vitro.[Methods]Carbomer 940,propylene glycol and absolute ethyl alcohol were selected as the main factors,and the preparation technology of C.bungei Steud.extract gel was optimized by orthogonal test.The mouse model of ulcerative hemorrhoids was established with glacial acetic acid(HAC)and compared with Ma Yinglong musk hemorrhoids ointment.The recovery of trauma was compared between the two groups.At the same time,porcine small intestine was used as semi-permeable membrane to make diffusion cell to simulate anal environment,and the drug release in vitro was studied.[Results]The C.bungei Steud.extract gel was smooth in appearance and good in stability.It could effectively treat anal ulcer in mice and release quickly in vitro.[Conclusions]The formula is reasonable,and the effect of animal experiment is remarkable,which can provide a new treatment plan for ulcerative hemorrhoids. 展开更多
关键词 Clerodendrum bungei Steud.extract gel Anorectal pharmacodynamics Diffusion cell Drug release MICE
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Rheological Properties of Six Plant-Based Seed Gums
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作者 Yongbo Chang yifei li +2 位作者 Quanquan Miao Huanshi Jiang Xin Gao 《American Journal of Analytical Chemistry》 2017年第11期690-707,共18页
The rheological properties of six mucilage solutions (Guar Gum, Locust Bean Gum, Tamarind Gum, Flaxseed Gum, Artemisia Sphaerocephala Krasch Gum and Cassia Gum) have been examined. It was found that all six gums could... The rheological properties of six mucilage solutions (Guar Gum, Locust Bean Gum, Tamarind Gum, Flaxseed Gum, Artemisia Sphaerocephala Krasch Gum and Cassia Gum) have been examined. It was found that all six gums could be classified into three different types according to the changes of viscosity with increasing shear rate. Steady shear viscous properties in a range of shear rate from 0.1 to 100 s-1 were investigated in the provision of mucilage concentration, pH, temperature and salts. A non-Newtonian shear-thinning behavior was observed. The data of viscosity-shear successfully correlated Power law model. Apparent viscosity was apparently dependent on mucilage concentration increasing significantly as mass fraction went up. A marked dependence of viscosity on temperature was also observed;as temperature increased, the viscosity decreased sharply. The value n of flaxseed gum is minimum, which means it behaves the greatest shear-thinning properties. Both Guar gum and Tamarind gum possessed better acid-proof and alkali-proof advantages. The flow activation energy of ASKG is 4.3 kcal which is higher than other gums so that the influence of temperature on characteristics of viscosity is stronger. The mechanical spectra in the linear viscoelasticity region were studied in the temperature range from 20&deg;C to 90&deg;C, at a frequency range from 0.1 to 10 Hz. It was observed that Both elastic modulus G' and viscous modulus G" behaviors were found to be dependent on temperature and frequency. What have been investigated in this work could provide guidance for practical application in the field of food industry. 展开更多
关键词 Plant-Based SEED GUMS RHEOLOGICAL Properties Viscosity Behavior Storage MODULUS Loss MODULUS
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Enhanced homing of mesenchymal stem cells for in situ niche remodeling and bone regeneration
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作者 Yin Yuan lijun Chen +9 位作者 Jing Yang Sining Zhou Yangxin Fang Qi Zhang Ning Zhang yifei li li Yuan Fan Jia Shuo Ni Charlie Xiang 《Nano Research》 SCIE EI CSCD 2024年第8期7449-7460,共12页
Mesenchymal stem cells(MSCs)transplantation is a promising strategy for osteoporosis treatment.However,limited sources and poor tissue-homing efficiency limit their clinical capabilities.In this study,we isolated a ki... Mesenchymal stem cells(MSCs)transplantation is a promising strategy for osteoporosis treatment.However,limited sources and poor tissue-homing efficiency limit their clinical capabilities.In this study,we isolated a kind of MSCs from women’s menstrual blood(MenSCs)noninvasively and established a novel MSCs bone marrow-targeted delivery system by utilizing waterin-oil-in-water droplet microfluidics.MenSCs were encapsulated withinβ-cyclodextrin-functionalized alginate microcapsules loaded with zoledronates,which has a high affinity for bone.With this delivery system,MenSCs could be preferentially delivered to the bone marrow tissues via intravenous infusion,and restored bone mass by remodeling the bone marrow niche in situ in ovariectomized mouse models.Moreover,scRNA-seq analysis demonstrated that those MenSCs homed to the bone marrow recruited CD4^(+)FOXP3^(+)natural regulatory T(nT_(reg))cells by secreting CCL28.The recruited nTreg promoted CD8^(+)T cells to secret Wnt family member 10B(WNT10B),activating the Wnt signaling in osteoblasts and thus promoting bone formation in situ in the bone marrow.This study reveals a promising application of MenSCs in postmenopausal osteoporosis treatment and highlights the clinical value of MenSCs by encouraging women to reserve autologous MenSCs before menopause to prevent and alleviate postmenopausal osteoporosis. 展开更多
关键词 mesenchymal stem cells MICROFLUIDICS bone marrow homing stem cell niche postmenopausal osteoporosis
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Zinc finger-inspired peptide-metal-phenolic nanointerface enhances bone-implant integration under bacterial infection microenvironment through immune modulation and osteogenesis promotion
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作者 lin Xu Jie Fang +7 位作者 Jiezhou Pan Hexu Qi Yun Yin Yunxiang He Xueqi Gan yifei li Yu li Junling Guo 《Bioactive Materials》 SCIE CSCD 2024年第11期564-576,共13页
Orthopedic and dental implantations under bacterial infection microenvironment face significant challenges in achieving high-quality bone-implant integration. Designing implant coatings that incorporate both immune de... Orthopedic and dental implantations under bacterial infection microenvironment face significant challenges in achieving high-quality bone-implant integration. Designing implant coatings that incorporate both immune defense and anti-inflammation is difficult in conventional single-functional coatings. We introduce a multifunctional nanointerface using a zinc finger-inspired peptide-metal-phenolic nanocoating, designed to enhance implant osseointegration under such conditions. Abaloparatide (ABL), a second-generation anabolic drug for treating osteoporosis, can be integrated into the design of a zinc-phenolic network constructed on the implant surface (ABL@ZnTA). Importantly, the phenolic-coordinated Zn2+ ions in ABL@ZnTA can act as zinc finger motif to co-stabilize the configuration of ABL through multiple molecular interactions, enabling high bioactivity, high loading capacity (1.36 times), and long-term release (>7 days) of ABL. Our results showed that ABL@ZnTA can modulate macrophage polarization from the pro-inflammatory M1 towards the anti-inflammatory M2 phenotype, promoting immune osteogenesis with increased OCN, ALP, and SOD 1 expression. Furthermore, the ABL@ZnTA significantly reduces inflammatory fibrous tissue encapsulation and enhances the long-term stability of the implants, indicated by enhanced binding strength (6 times) and functional connectivity (1.5−3 times) in the rat bone defect model infected by S. aureus. Overall, our research offers a nano-enabled synergistic strategy that balances infection defense and osteogenesis promotion in orthopedic and dental implantations. 展开更多
关键词 Metal-phenolic network IMPLANT OSSEOINTEGRATION Inflammation Abaloparatide
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