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The compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one alleviates neuroinflammation and cognitive impairment in a mouse model of Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3330-3344页

作者： Xueyan Liu Wei Wu Xuejuan Li Chengyan Wang Ke Chai Fanru Yuan Huijuan Zheng Yuxing Yao Chenlu Li Zu-Cheng Ye Daijun zha Department of Medicinal Chemistry School of PharmacyFujian Medical UniversityFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Brain Aging and Neurodegenerative diseases School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Institute of Laboratory Animal Center Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurosurgery Neurosurgery Research InstituteThe First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina Department of Hyperbaric Oxygen National Regional Medical CenterBinhai Campus of the First Affiliated HospitalFujian Medical UniversityFuzhouFujian ProvinceChina

Previous studies have shown that the compound(E)-2-(3,4-dihydroxystyryl)-3-hydroxy-4H-pyran-4-one(D30),a pyromeconic acid derivative,possesses antioxidant and anti-inflammatory properties,inhibits amyloid-β aggregation,and alleviates scopolamine-induced cognitive impairment,similar to the phase Ⅲ clinical drug *** this study,we established a mouse model of Alzheimer's disease via intracerebroventricular injection of fibrillar amyloid-β to investigate the effect of D30 on fibrillar amyloid-β-induced *** results showed that D30 alleviated fibrillar amyloid-β-induced cognitive impairment,promoted fibrillar amyloid-β clearance from the hippocampus and cortex,suppressed oxidative stress,and inhibited activation of microglia and astrocytes.D30 also reversed the fibrillar amyloid-β-induced loss of dendritic spines and synaptic protein ***,we demonstrated that exogenous fibrillar amyloid-βintroduced by intracerebroventricular injection greatly increased galectin-3 expression levels in the brain,and this increase was blocked by *** the role of D30 in clearing amyloid-β,inhibiting neuroinflammation,protecting synapses,and improving cognition,this study highlights the potential of galectin-3 as a promising treatment target for patients with Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β astrocyte cognitive impairment D30 dendritic spines galectin-3 microglia neuroinflammation neuron

晋西黄土区不同植被恢复阶段土壤生态化学计量特征

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水土保持研究 2025年第1期32卷 30-38+47页

作者：高连炜张红丽查同刚北京林业大学水土保持学院水利部水土保持监测中心

[目的]开展土壤生态化学计量特征随植被恢复进程的变化研究，探究植被恢复引起土壤养分变化规律及其作用机制，对认识植被恢复与土壤养分的关系，指导植被恢复实践具有重要意义。[方法]以晋西黄土区不同植被恢复阶段(撂荒地、草地、灌... 详细信息

[目的]开展土壤生态化学计量特征随植被恢复进程的变化研究，探究植被恢复引起土壤养分变化规律及其作用机制，对认识植被恢复与土壤养分的关系，指导植被恢复实践具有重要意义。[方法]以晋西黄土区不同植被恢复阶段(撂荒地、草地、灌木林、先锋阔叶林、针叶林)的5种林(草)地为研究对象，通过调查采样和室内分析，探究土壤生态化学计量特征随植被恢复的进程变化及其影响因素。[结果](1)随着植被的恢复，先锋阔叶林和针叶林阶段的SOC含量较上一阶段增加19.8%,土壤TN含量较上一阶段增加17.6%,而土壤TP含量较上一阶段减少12.4%;(2)随着植被恢复的发展，土壤C∶P和N∶P显著增加，C∶N的变化无明显规律，在先锋阔叶林和针叶林阶段的土壤C∶P较上一阶段增加26.6%;先锋阔叶林和针叶林阶段在0—40 cm土层的土壤N∶P较上一阶段增加40.2%,40—100 cm土层的土壤N∶P较上一阶段增加35.7%;土壤C∶N在不同植被恢复阶段间的变化未见明显规律，研究区土壤逐渐由C,N的限制转变为P的限制；(3)各植被恢复阶段土壤C∶P和N∶P主要与砂粒含量呈显著负相关，与孔隙度呈显著正相关，土壤C∶N与其他因子的相关性不明显。[结论]植被恢复有利于土壤C,N含量增加，改善土壤理化性质，在植被恢复过程应同时注重P元素的调控，以提高晋西黄土区植被生态恢复水平。

关键词：植被恢复土壤养分生态化学计量特征

Production of anthocyanins in metabolically engineered microorganisms:Current status and perspectives

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Synthetic and Systems Biotechnology 2017年第4期2卷 259-266页

作者： Jian zha Mattheos A.g.Koffas Department of Chemical and Biological Engineering Center for Biotechnology and Interdisciplinary StudiesRensselaer Polytechnic InstituteTroyNYUSA Department of Biological Sciences Center for Biotechnology and Interdisciplinary StudiesRensselaer Polytechnic InstituteTroyNYUSA

Microbial production of plant-derived natural products by engineered microorganisms has achieved great success thanks to large extend to metabolic engineering and synthetic ***,the water-soluble colored pigments found in terrestrial plants that are responsible for the red,blue and purple coloration of many flowers and fruits,are extensively used in food and cosmetics industry;however,their current supply heavily relies on complex extraction from plant-based materials.A promising alternative is their sustainable production in metabolically engineered ***,we review the recent progress on anthocyanin biosynthesis in engineered bacteria,with a special focus on the systematic engineering modifications such as selection and engineering of biosynthetic enzymes,engineering of transportation,regulation of UDP-glucose supply,as well as process *** promising engineering strategies will facilitate successful microbial production of anthocyanins in industry in the near future.

关键词： Anthocyanin Enzyme engineering Metabolic engineering Microbial production

Numerical Study on Aerodynamic Performance of Floating Dual-Rotor Wind Turbines in Heave and Surge Motions

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China Ocean Engineering 2023年第6期37卷 1011-1021页

作者： WU Xiao-di LU Wen-hao WANg Kai HU Wei-fei FANg Jian-hao zha Ruo-si School of Ocean Engineering and Technology Sun Yat-sen University&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519000China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China School of Mechanical Engineering Zhejiang UniversityHangzhou 310058China

Compared with the traditional wind turbine of a single rotor,dual-rotor wind turbines(DRWTs)have higher wind energy capture efficiency and a more complex ***,the aerodynamic performance of the DRWT installed on the floating platform will be greatly affected by the motion caused by wind and wave *** this paper,5 MW and 750 kW single rotor wind turbines(SRWTs)are combined into a 5 MW-5 MW DRWT and a 5 MW-750 kW DRWT,and their power output and wake field characteristics in different motions are *** flow field is obtained by solving the Reynolds-averaged Navier–Stokes equation(RANS).The overset grid technique is employed to achieve the large-amplitude multiple-degree-of-freedom motion of the *** overall performance of the 5 MW single rotor wind turbine is determined by a numerical *** the DRWTs,numerical results show that the surge motion and heave motion both have a negative effect on the power output of the *** surge motion is a critical factor that causes the power output of the DRWT to periodically change with *** average power output of the DRWT influenced by motion is lower than that of a DRWT with a fixed *** surge motion significantly disturbs the wake of the DRWT due to the mutual interference between the upstream and downstream *** the influence of heave motion,low-velocity regions downstream of the blade tip are *** study indicates that attenuating the surge and heave motion of offshore DRWT is very significant for improving its efficiency and should be taken into consideration during the design procedure.

关键词： DRWT surge motion heave motion wake field power output

HOMOMORPHISMS BETWEEN CHEVALLEY gROUPS OF TYPES C_nAND g_2 OVER FINITE FIELDS

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Chinese Annals of Mathematics,Series B 1997年第2期18卷 167-172页

作者： zha JIANgUO Department of Applied Mathematics Tongji UniversityShanghai 200092China

It is known that there exists an isogeny sort of Chevalley groups g (Σ, F) associated to any indecomposable root system Σ and any field F . In this paper the author determines all nontrivial homomorphisms from g(Σ, k) to g(Σ, K) when the root system Σ is of type C n or g 2 , and the fields k and K are finite fields of characteristic p .

关键词： Chevalley group Homomorphism Finite field

geometric Error Identification of gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： Jun zha Huijie zha.g School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool geometric error Error separation

All-optical logic gates based on hierarchical photonic crystal modulated photoluminescence of perovskite nanocrystals

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Science China(Technological Sciences) 2023年第9期66卷 2735-2742页

作者： WANg Yun zha YanFang YANg YunYi LIU CiHui di YunSong CAO guiYuan WEI ShiBiao CHEN ZhiHui gAN ZhiXing Center for Future Optoelectronic Functional Materials School of Computer and Electronic InformationSchool of Artificial IntelligenceNanjing Normal UniversityNanjing 210023China Centre for Translational Atomaterials School of ScienceSwinburne University of TechnologyHawthorn VIC 3122Australia Nanophotonics Research Center Shenzhen Key Laboratory of Micro-Scale Optical Information TechnologyShenzhen UniversityShenzhen 518060China Key Laboratory of Advanced Transducers and Intelligent Control Systems Ministry of Education and Shanxi ProvinceCollege of Electronic Information and Optical EngineeringTaiyuan University of TechnologyTaiyuan 030024China

Halide perovskites exhibit high performance in all sorts of optoelectronic and photonic areas, suggesting their huge potential in integrated photonic devices. However, until now, all optical logic gates based on perovskites are still rarely explored, hindering the development of all-optical networks and computing. Herein, a new concept of all-optical logic gates is proposed based on the modulation of photoluminescence(PL) from perovskite nanocrystals(PNCs). A hierarchical photonic crystal(Hie PhC) is developed by self-assembling polystyrene(PS) and SiO2nanoparticles, which exhibit a higher PL enhancement than that of a monolayer PhC. Moreover, the light-controlled PL is realized by taking advantage of the high thermal response of the PL from PNCs/Hie PhC on polyethylene(PE) substrate, assisted by a graphene layer for light-heat conversion. Consequently, optical diode and triode are achieved based on the modulated PL, which exhibit contrast ratios(CR) of 24.7 and 74.0 dB, ***-optical logic gates, including “AND”, “OR” and “NOT”, are realized based on the optical diode and triode.

关键词： perovskite nanocrystals photonic crystals all-optical logic gates modulation of photoluminescence

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Evasion strategies of a three-player lifeline game

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Science China(Information Sciences) 2018年第11期61卷 144-154页

作者： Fan zha.g Wenzhong zha School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System Information Science Academy China Electronics Technology Group Corporation

This study examines a multi-player pursuit-evasion game, more specifically, a three-player lifeline game in a planar environment, where a single evader is tasked with reaching a lifeline prior to capture. A decomposition method based on an explicit policy is proposed to address the game qualitatively from two main aspects:(1) the evader’s position distribution to guarantee winning the game(i.e., the escape zone),which is based on the premise of knowing the pursuers’ positions initially, and(2) evasion strategies in the escape zone. First, this study decomposes the three-player lifeline game into two two-player sub-games and obtains an analytic expression of the escape zone by constructing a barrier, which is an integration of the solutions of two sub-games. This study then explicitly partitions the escape zone into several regions and derives an evasion strategy for each region. In particular, this study provides a resultant force method for the evader to balance the active goal of reaching the lifeline and the passive goal of avoiding capture. Finally,some examples from a lifeline game involving more than one pursuer are used to verify the effectiveness and scalability of the evasion strategies.

关键词： lifeline game three-player pursuit-evasion game barrier evasion strategy game of kind

Adaptive learning algorithm based on mixture gaussian background

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Journal of Systems Engineering and Electronics 2007年第2期18卷 369-376页

作者： zha Yufei Bi Duyan Signal and Information Processing Lab Engineering Coll. of Air Force Engineering Univ. Xi'an 710038 P. R. China

The key problem of the adaptive mixture background model is that the parameters can adaptively change according to the input data. To address the problem, a new method is proposed. Firstly, the recursive equations are inferred based on the maximum likelihood rule. Secondly, the forgetting factor and learning rate factor are redefined, and their still more general formulations are obtained by analyzing their practical functions. Lastly, the convergence of the proposed algorithm is proved to enable the estimation converge to a local maximum of the data likelihood function according to the stochastic approximation theory. The experiments show that the proposed learning algorithm excels the formers both in converging rate and accuracy.

关键词： Mixture gaussian model Background model, Learning algorithm.