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Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang yi-De zhang Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-yian guo jian-Gang Shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Chip-Level MMSE Equalization for CDMA Downlink

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The Journal of China Universities of Posts and Telecommunications 2005年第2期12卷 82-86页

作者： zhang yi gu jian yang da-cheng Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

This work is focused on the structure design of MMSE linear equalizers in the downlink of CDMA-based multi-user communication systems. Previous work was mostly focused on the performance comparison between ZF and MMSE linear equalizers and the conclusion is that the performance based on MMSE criterion is much better than that based on ZF one. In this paper, we only discuss MMSE equalizer and a new block structure of MMSE linear equalizer is derived from the traditional structure of this kind of equalizer. Furthermore, a block MMSE linear equalizer is improved through using the overlap-save technique. Simulation results shaw that the average performance of improved block MMSE linear equalizers is better than those of the block MMSE equalizers and traditional MMSE equalizers. At the same time, the computation complexity of all these MMSE equalizers is given. It is shown that the comple：rity of proposed block MMSE equalizers is lower than that of the traditional equalizers with optimal delay, D, when the length of the filter in traditional MMSE equalizers equals the block size of block MMSE equalizers.

关键词： MMSE ZF equalization chip-level overlap

Hemin-histamine-montmorillonite clay conjugate as a model biocatalyst to mimic natural peroxidase

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Science China Chemistry 2015年第4期58卷 731-737页

作者： Lihui zhang cheng gu jian Xiong Mei yang Yong guo State Key Laboratory of Pollution Control & Resource Reuse School of the Environment Nanjing University

We successfully synthesized the first hemin-montmorillonite bio-conjugate with an amino acid residue to mimic natural peroxidase enzyme. Histamine was intercalated in montmorillonite by cation exchange, then a heroin molecule was loaded onto the histamine-montmorillonite with an adsorption capacity of 7.0 mg· g^-1. The hemin-histamine-montmorillonite conjugate shows high peroxidase activity as indicated by the oxidation of guaiacol, which is attributed to the activation of hemin by Fe-N complex formation between the imidazole group in histamine and the iron ion in the hemin molecule. Temperaturedependent peroxidase activity for this synthesized biomimetic material indicates that raising the reaction temperature could significantly enhance the activity of the conjugate. The biomimetic catalyst has good reusability; nearly 100% activity can be retained after three cycles. Because montmorillonite clay is widely distributed in the environment, this material offers great potential for in situ and ex situ remediation of many organic contaminants in surface/subsurface soils.

关键词： hemin-histamine-montmorillonite conjugates imidazole biomimetic catalyst peroxidase activity recycle

浑水入渗对粗粒土柱孔隙及渗透性影响试验研究

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岩土工程学报 2025年第1期47卷 173-183页

作者：毛海涛张超袁古城何涛谷易山西农业大学城乡建设学院山西太原030000 重庆三峡学院土木工程学院重庆404120

浑水渗流在水利工程的反滤设计、浑水浇灌、堤坝渗流控制等方面都有较大影响,目前理论多采用稳定渗流计算方法,忽略了渗流过程中粗细颗粒与水力的耦合作用。自制渗流装置,将不同控制粒径浑水、不均匀系数粗粒土柱和水头等作为基本控制因... 详细信息

浑水渗流在水利工程的反滤设计、浑水浇灌、堤坝渗流控制等方面都有较大影响,目前理论多采用稳定渗流计算方法,忽略了渗流过程中粗细颗粒与水力的耦合作用。自制渗流装置,将不同控制粒径浑水、不均匀系数粗粒土柱和水头等作为基本控制因素,研究不同工况下浑水中悬浮颗粒对粗粒土土柱中的渗透特性影响;推导了变渗透系数浑水渗流计算微分方程,通过对比验证和公式修正,结果表明:粗粒土中颗粒淤积率与控制粒径C_(0.075)含量符合Boltzmann函数关系;C_(0.075)是重要的影响因子,浑水颗粒在粗粒土柱的运移、沉积和淤堵形态过程大致可分为4种形态:表层堆积淤堵形态(S型);表层-内部双重淤堵形态(S-I型);内部孔隙淤堵形态(I型);暂态孔隙淤堵形态(P型)。土柱C_(u)越大,孔隙度越小,浑水颗粒在粗粒土中运移也越困难,土柱填充性就越差;水头加剧了颗粒在土柱内部运移的速度,但也加速了其在顶部的沉积并封堵;S型时土柱0~2cm渗透系数下降速率最大,封堵时总体渗透系数最小,2cm以下相对孔隙率及随深度逐渐减小;S-I和I型土柱下部渗透系数明显滞后于上部,相对孔隙率存在临界深度(约为4~6cm);P型时土柱整体相对孔隙率基本无变化。

关键词：颗粒渗流粗粒土浑水堵塞

Study on products and reaction paths for synthesis of 3,4-dihydro-2H-3-phenyl-1,3-benzoxazine from phenol,aniline and formaldehyde

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Chinese Chemical Letters 2015年第3期26卷 348-352页

作者： cheng-Xi zhang Yu-Yuan Deng yi-yang zhang Po yang yi gu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan University

To study the synthesis of 3,4-dihydro-2H-3-phenyl-1,3-benzoxazine（benzoxazine）,the reaction paths of phenol,aniline and formaldehyde were investigated by analyzing the synthesis crude *** the aid of high-performance liquid chromatography（HPLC）,chromatographic column and preparative HPLC,seven compounds originated from the crude products were obtained and their chemical structures were *** reaction paths are proposed based on these *** show that Nhydroxymethyl aniline（HMA） derived from the reaction of formaldehyde and aniline is probably the key intermediate during the *** can react with itself or other reactants to form other intermediates,such as 1,3,5-triphenyl-1,3,5-triazinane and 2-（（phenylamino）methyl）phenol,and further form benzoxazine and byproducts.

关键词： aniline phenol formaldehyde itself crude originated react monomer probably claimed

Vapor-assisted epitaxial growth of porphyrin-based MOF thin film for nonlinear optical limiting

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Science China Chemistry 2020年第8期63卷 1059-1065页

作者： yi-Hong Xiao Zhi-Gang gu jian zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China

Fabrication of metal-organic frameworks(MOFs)thin films has been an efficient way to expand their functionalities and ***,we use the vapor-assisted deposition(VAD)method to epitaxially grow a porphyrin-based MOF PCN-222 *** is,vapor source assists to deposit pre-treated precursor solution on quartz substrate to form a continuous PCN-222 ***,utilizing the post-treated encapsulation of functional carbon-based nanoparticles,the carbon nanodots(CND)and Pt doped CND(Pt/CND)are well loaded into the pores of PCN-222 film,the size(~3.1 nm)of which is highly close to the pore size of the corresponding MOF(~3.7 nm).The Z-scan results reveal that PCN-222 film exhibits high reverse saturable *** addition,encapsulation of carbon based nanodots into PCN-222 film could enhance the nonlinear optical limiting effect benefiting from the host-guest *** study serves to present both the available toolbox of thin film preparation and high potential for precise synthetic nanocomposite films in optical limiting devices.

关键词： metal-organic framework epitaxial growth porphyrin thin film nonlinear optical property

Ab initio Study on Structures and Isomerization of Magnesium Fluorosilylenoid H2SiFMgF

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Chinese Journal of Chemical Physics 2008年第6期21卷 541-546页

作者： yi-jian zhang Mei-jiang Li guo-qiao Lai da-cheng Feng Sheng-yu Feng Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal University Hangzhou 310012 China School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China

The structures and isomerization of magnesium fluorosilylenoid H2SiFMgF were investigated by ab initio molecular orbital theory. Four equilibrium structures and three isomeric transition states were located and fully optimized at the B3LYP/6-31G（d,p） and G3MP2B3 levels, respectively. Based on the B3LYP/6- 31G（d,p） optimized geometries, harmonic frequencies of various structures were obtained and 29Si chemical shifts were calculated. The solvent effects were investigated by means of the polarizable continuum model using THF as a solvent at B3LYP/6-31G（d,p） level. Isomerization paths for isomers were confirmed by intrinsic reaction coordinate calculations. The calculated results show that tetrahedral structure has the lowest energy and is the most stable; tetrahedral, three-membered ring, and p-complex structures are suggested to be the experimentally detectable ones; and a-complex structure has the highest energy and will not exist.

关键词： Magnesium fluorosilylenoid Ab initio calculation B3LYP/6-31G(d p) theory Isomerization

New CFAR target detector for SAR images based on kernel density estimation and mean square error distance

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Journal of Systems Engineering and Electronics 2012年第1期23卷 40-46页

作者： yi Cui jian yang Xinzheng zhang Department of Electronic Engineering Tsinghua University Beijing 100084 P. R. China Beijing Institute of Environmental Features Beijing 100854 R R. China

A new constant false alarm rate （CFAR） target detector for synthetic aperture radar （SAR） images is developed. For each pixel under test, both the local probability density function （PDF） of the pixel and the clutter PDF in the reference window are estimated by the non-parametric density estimation. The target detector is defined as the mean square error （MSE） distance between the two PDFs. The CFAR detection in SAR images having multiplicative noise is achieved by adaptive kernel bandwidth proportional to the clutter level. In addition, for obtaining a threshold with respect to a given probability of false alarm （PFA）, an unsupervised null distribution fitting method with outlier rejection is proposed. The effectiveness of the proposed target detector is demonstrated by the experiment result using the RAdaTSAT-2 SAR image.

关键词： synthetic aperture radar (SAR) target detection con- stant false alarm rate (CFAR).

Metal–Organic Framework‑Based Photodetectors

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Nano-Micro Letters 2024年第11期16卷 675-703页

作者： Jin‑Biao zhang yi‑Bo Tian Zhi‑Gang gu jian zhang State Key Laboratory of Structural Chemistry Structure of MatterFujian Institute of ResearchChinese Academy of SciencesFuzhouFujian 350002People’s Republic of China College of Chemistry and Materials Science Fujian Nornal UniversityFuzhou 350007FujianPeople’s Republic of China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108FujianPeople’s Republic of China University of Chinese Academy of Science Beijing 100049People’s Republic of China

The unique and interesting physical and chemical properties of metal–organic framework(MOF)materials have recently attracted extensive attention in a new generation of photoelectric *** this review,we summarized and discussed the research progress on MOF-based *** methods of preparing MOF-based photodetectors and various types of MOF single crystals and thin film as well as MOF composites are introduced in ***,the photodetectors applications for X-ray,ultraviolet and infrared light,biological detectors,and circularly polarized light photodetectors are ***,summaries and challenges are provided for this important research field.

关键词： Metal-organic frameworks Semiconductor Photodetectors