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Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan Guo Qianqian shao Xunming ji jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

Damage evolution model of strain hardening cementitious composites under the uniaxial stress state

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 196-204页

作者： Rui He Shuan-fa Chen pei-liang Cong shao-hua ji School of Highway Chang'an University Via Department of Civil and Environmental Engineering Virginia Polytechnic Institute and State UniversityBlacksburg VA 24061USA Engineering Research Center of the Ministry of Education for Transportation Materials Chang'an University

The deformation and damage behaviors of strain hardening cementitious composites （SHCC） under the uniaxial stress state were investigated in this paper. Two ductile failure-based constitutive models were introduced to describe the uniaxial tension and compression properties of SHCC only using a few parameters. The computation method of model parameters was developed to ease the simulation procedures. Damage evolution of the SHCC was simulated by the formulation of continuum damage mechanics subsequently. The results show that the proposed models fit the stress-strain curves reasonably well, and the damage variables show different growth rules under uniaxial tension and compression. It is concluded that the proposed method can not only simply simulate the constitutive behavior of SHCC with the reasonable accuracy but also capture the characteristic of material degradation.

关键词： cementitious composites strain hardening constitutive models ductile fracture continuum damage mechanics

High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： Man Zhang Xiao-Xu Liu Tian-Yi ji Yang Li Da-Wei Sheng shao-Dong Li pei-pei Ren Ze-Xiang Shen School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone(ZIF) and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber(CoP@CF) were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g^(-1) at 0.1 A·g^(-1)after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·g^(-1).The sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Freestanding anodes Sodium-ion batteries

Biogenic gas generation effects on anthracite molecular structure and pore structure

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Frontiers of Earth Science 2021年第2期15卷 272-282页

作者： Aikuan WANG pei shao Qinghui WANG Key Laboratory of Coalbed Methane Resources&Reservoir Formation Process(Ministry of Education) China University of Mining&TechnologyXuzhou 221008China School of Resources and Geosciences China University of Mining&TechnologyXuzhou 221116China Department of Surveying and Planning Shangqiu Normal UniversityShangqiu 476000China

This study carries out a simulated experiment of biogenic gas generation and studies the effects of gas generation on the pore structure and molecular structure of anthracite by mercury intrusion porosimetry,X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FT-IR).The results show that methanogenic bacteria can produce biogenic gas from ***_(2) and CH4 are the main components of the generated *** generation,some micropores(100 MPa)of the mercury intrusion test,the specific surface area decreases by 19.79%compared with that of raw coal,and the pore volume increases by 7.25%in *** action on the molecular structure causes changes in the pore *** FT-IR data show that the side chains and hydroxyl groups of the coal molecular structure in coal are easily metabolized by methanogenic bacteria and partially oxidized to form carboxylic *** addition,based on the XRD data,the aromatic lamellar structure in the coal is changed by microorganisms;it decreases in lateral size(La)and stacking thickness(Lc).This study enriches the theory of biogenic coalbed gas generation and provides a pathway for enhancing the permeability of high-rank coal reservoirs.

关键词： biogenic gas anthracite pore structure molecular structure

Characteristics and distribution of phosphorus in surface sediments of a shallow lake

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Journal of Environmental Sciences 2023年第2期124卷 50-60页

作者： Ziwei Long Zehua ji Yuansheng pei State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China The Key Laboratory of Water and Sediment Sciences Ministry of EducationSchool of EnvironmentBeijing Normal UniversityBeijing 100875China

Phosphorus(P)in sediments plays an important role in shallow lake ecosystems and has a major effect on the lake *** mobility and bioavailability of P primarily depend on the contents of different P forms,which in turn depend on the sedimentary ***,sediment samples from Baiyangdian(BYD)lake were collected and measured by the Standards,Measurements,and Testing procedure and Phosphorus-31 nuclear magnetic resonance spectroscopy(31P NMR)to characterize different P forms and their relationships with sediment physicochemical *** P content in the sediments varied in different areas and had characteristics indicative of exogenous river *** P(334–916 mg/kg)was the dominant form of *** 31P NMR results demonstrated that orthophosphate monoesters(16–110 mg/kg),which may be a source of P when redox conditions change,was the dominant form of organic P(20–305 mg/kg).The distribution of P forms in each region varied greatly because of the effects of anthropogenic activities,and the regions affected by exogenous river input had a higher content of P and a higher risk of P *** component analysis indicated that P bound to Fe,Al,and Mn oxides and hydroxides(NaOH-P)and organic P were mainly derived from industrial and agricultural pollution,*** analysis indicated that increases in pH lead to the release of *** matter plays an important role in the organic P biogeochemical cycle,as it acts as a sink and source of organic P.

关键词： Sediment Phosphorus forms SMT 31P NMR

Effects of Exogenous Silicon on the Activities of Antioxidant Enzymes and Lipid Peroxidation in Chilling-Stressed Cucumber Leaves

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Agricultural Sciences in China 2009年第9期8卷 1075-1086页

作者： LIU jiao-jing LIN shao-hang XU pei-lei WANG Xiu-juan BAI ji-gang State Key Laboratory of Crop Biology/College of Life Sciences Shandong Agricultural UniversityTai’an 271018P.R.China

In order to increase vegetable productivity by improving environmental conditions, this article investigates the effects of exogenous silicon on the activities of major antioxidant enzymes and on lipid peroxidation under chilling stress, and it examines whether silicon-induced chilling tolerance is mediated by an increase in antioxidant activity. Cucumis sativus cv. jinchun 4 was hydroponically cultivated to the two-leaf stage, at which point seedlings were watered with different concentrations of silicon (0, 0.1 and 1 mmol L^-1) and separately exposed to normal (25/18℃) or chilling (15/8℃) temperatures for six days under low light (100μmol m^-2 s^-9. Data were collected from the second leaves on the percentage of withering and the levels of endogenous silicon, malondialdehyde (MDA), hydrogen peroxide (H202), superoxide radical (O2^.-), superoxide dismutase (SOD, EC 1.***.1.1), glutathione peroxidase (GSH-Px, EC 1.***.1.9), ascorbate peroxidase (APX, EC 1.***.1.11), monodehydroascorbate reductase (MDHAR, EC 1.***.5.4), glutathione reductase (GR, EC 1.***.4.2), reduced glutathione (GSH) and ascorbate (AsA). Compared to normal temperatures, chilling resulted in partially withered leaves and increased MDA content. When 0.1 or 1 mmol L^-1 exogenous silicon was combined with chilling, the withering of the cucumber leaves was reduced relative to the original chilling treatment, while the endogenous silicon content was increased, antioxidants such as SOD, GSH-Px, APX, MDHAR, GR, GSH, and AsA were more active, and the levels of H2O2, O2^.-, and MDA were lower. We propose that exogenous silicon leads to greater deposition of endogenous silicon and thereby increases antioxidant activities and reduces lipid peroxidation induced by chilling.

关键词： antioxidant enzyme chilling Cucumis sativus lipid peroxidation silicon

Scalar dark energy models and scalar–tensor gravity:theoretical explanations for the accelerated expansion of the present Universe

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Communications in Theoretical Physics 2024年第10期76卷 158-187页

作者： peixiang ji Lijing shao Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

The reason for the present accelerated expansion of the Universe stands as one of the most profound questions in the realm of science,with deep connections to both cosmology and fundamental *** a cosmological point of view,physical models aimed at elucidating the observed expansion can be categorized into two major classes:dark energy and modified *** review various major approaches that employ a single scalar field to account for the accelerating phase of our present *** system analysis was employed in several important models to find cosmological solutions that exhibit an accelerating phase as an *** scalar field models of dark energy,we consistently focused on addressing challenges related to the fine-tuning and coincidence problems in cosmology,as well as exploring potential solutions to *** scalar–tensor theories and their generalizations,we emphasize the importance of constraints on theoretical parameters to ensure overall consistency with experimental *** or theories that could potentially explain the Hubble tension are also emphasized throughout this review.

关键词： dark energy modified gravity quintessence dynamic system cosmology

First passage probabilities of one-dimensional diffusion processes

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Frontiers of Mathematics in China 2015年第4期10卷 901-916页

作者： Huijie ji jinghai shao School of Mathematical Sciences Beijing Normal University Beijing 100875 China College of Mathematics and Computer Science Shanxi Normal UniversityLinfen 041000 China

This work is devoted to calculating the first passage probabilities of one-dimensional diffusion processes. For a one-dimensional diffusion process, we construct a sequence of Markov chains so that their absorption probabilities approximate the first passage probability of the given diffusion process. This method is especially useful when dealing with time-dependent boundaries.

关键词： Boundary crossing probability first passage probability Markovchain Skorokhod approximation

Parametric Resonance Analyses for Spar Platform in Irregular Waves

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China Ocean Engineering 2018年第2期32卷 236-244页

作者： YANG He-zhen XU pei-ji School of Engineering University of GlasgowGlasgow G128QQUnited Kingdom School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The parametric instability of a spar platform in irregular waves is analyzed. Parametric resonance is a phenomenon that may occur when a mechanical system parameter varies over time. When it occurs, a spar platform will have excessive pitch motion and may capsize. Therefore, avoiding parametric resonance is an important design requirement. The traditional methodology includes only a prediction of the Mathieu stability with harmonic excitation in regular waves. However, real sea conditions are irregular, and it has been observed that parametric resonance also occurs in non-harmonic excitations. Thus, it is imperative to predict the parametric resonance of a spar platform in irregular waves. A Hill equation is derived in this work, which can be used to analyze the parametric resonance under multi-frequency excitations. The derived Hill equation for predicting the instability of a spar can include non-harmonic excitation and random phases. The stability charts for multi-frequency excitation in irregular waves are given and compared with that for single frequency excitation in regular waves. Simulations of the pitch dynamic responses are carried out to check the stability. Three-dimensional stability charts with various damping coefficients for irregular waves are also investigated. The results show that the stability property in irregular waves has notable differences compared with that in case of regular waves. In addition, using the Hill equation to obtain the stability chart is an effective method to predict the parametric instability of spar platforms. Moreover, some suggestions for designing spar platforms to avoid parametric resonance are presented, such as increasing the damping coefficient, using an appropriate RAO and increasing the metacentric height.

关键词： spar platform instability parametric resonance Mathieu equation irregular waves dynamic responses