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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2982-2997页

作者： Hongli Li Jianhua Huang Di Zhao Lemei Zhu Zheyu Zhang min Yi Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Metabolic Diseases ChangshaHunan ProvinceChina Hunan Academy of Chinese Medicine ChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut *** aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease *** do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of ***-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 ***,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 *** findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

关键词： Alzheimer’s disease APP/PS1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis

Cross-correlation of 21 cm and soft X-ray backgrounds during the epoch of reionization

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Research in Astronomy and Astrophysics 2016年第8期16卷 135-144页

作者： Jun-min Liang xiao-chun Mao Bo Qin National Astronomical Observatories Chinese Academy of Sciences

The cross-correlation between the high-redshift 21 cm background and the Soft X-ray Background （SXB） of the Universe may provide an additional probe of the Epoch of Reionization. Here we use semi-numerical simulations to create 21 cm and soft X-ray intensity maps and construct their cross power spectra. Our results indicate that the cross power spectra are sensitive to the thermal and ionizing states of the intergalactic medium （IGM）. The 21 cm background correlates positively to the SXB on large scales during the early stages of the reionization. However as the reionization develops, these two back- grounds turn out to be anti-correlated with each other when more than - 15% of the IGM is ionized in a warm reionization scenario. The anti-correlated power reaches its maximum when the neutral fraction declines to 0.2-0.5. Hence, the trough in the cross power spectrum might be a useful tool for tracing the growth of HII regions during the middle and late stages of the reionization. We estimate the detectability of the cross power spectrum based on the abilities of the Square Kilometre Array and the Wide Field X-ray Telescope （WFXT）, and find that to detect the cross power spectrum, the pixel noise of X-ray images has to be at least 4 orders of magnitude lower than that of the WFXT deep survey.

关键词： cosmic background radiation -- cosmology: theory -- dark ages reionization first stars --early Universe -- diffuse radiation -- X-rays: diffuse background

Stable metal-organic frameworks with high catalytic performance in the cycloaddition of CO_2 with aziridines

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Science China Chemistry 2019年第5期62卷 622-628页

作者： xiao-min Kang Ying Shi chun-Shuai Cao Bin Zhao College of Chemistry and Key Laboratory of Advanced Energy Material Chemistry Nankai University

Based on the mixed ligands XN(4′-(4-pyridine)4,2′:2′,4′′-terpyridine) and isophthalic acid(IPA), three new metal-organic frameworks(MOFs) {[M_2(XN)_2(IPA)_2]·2 H_2O}_n(M=Co(1), Mn(2), Ni(3)) were assembled and structurally characterized,presenting 3 D pillar-chain feature structures. Stability measurements demonstrate that these compounds possess high thermostability and can endure different organic solvents as well as various acid/base solutions with pH range of 1 to 14. Importantly,compounds 1–3 can serve as high-efficiency catalysts for the transformation of CO_2 and aziridines to form high-value oxazolidinones under mild conditions, exhibiting excellent cyclicity at least five times.

关键词： MOFs stability catalysis oxazolidinones CO2 conversion

Influence of plasma peening on oxidation of H13 hot work steel in water vapor

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中国有色金属学会会刊：英文版 2004年第z1期14卷 305-309页

作者： min Yong-an XU xiao WU xiao-chun LI Lin XU Luo-ping School of Materials Science and Engineering Shanghai University Shanghai 200072 China School of Materials Science and Engineering Shanghai University Shanghai 200072 China School of Materials Science and Engineering Shanghai University Shanghai 200072 China School of Materials Science and Engineering Shanghai University Shanghai 200072 China School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The surface oxidation films on H13 steel samples, obtained by different oxidation processes were observed by optical microscope. It is shown that the oxidation speed of H13 steel is increased remarkably due to the surface modification of plasma peening. Further researches were made by XRD, SEM and EDS. The activation of H13 surface caused by plasma peening and the subsequent higher oxygen diffusion rate into the steel seem to be the main reasons of higher oxidation speed. The nitride layer, generally formed on the steel surface under plasma nitriding process, can be substituted by oxide in subsequent oxidation process, which can reduce the risk of heat cracking in some hot work applications. Therefore, the plasma nitriding plus oxidation process is a proper choice for some hot work dies, which demands high hardness to avoid indentation as well as high toughness to avoid cracks.

关键词： oxidation hot work tool steel plasma nitriding surface treatment

Three-Di mensional Model for Strip Hot Rolling

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Journal of Iron and Steel Research International 2006年第1期13卷 23-26页

作者： ZHANG Guo-min xiao Hong WANG chun-hua Engineering College Yanshan University Qinhuangdao 066004 Hebei China

A three-dimensional model for strip hot rolling was developed, in which the plastic deformation of strip, the thermal crown of rolls, roll deflection and flattening were calculated by rigid-plastic finite element method, finite difference method, influential function method and elastic finite element method respectively. The roll wear was taken into consideration. The model can provide detailed information such as rolling pressure distribution, contact pressure distribution between backup rolls and work rolls, deflection and flattening of work rolls, lateral distribution of strip thickness, and lateral distribution of front and back tensions. The finish rolling on a 1 450 mm hot strip mill was simulated.

关键词： strip hot rolling model finite difference method influential function method finite element method

Tempering stability of Fe–Cr–Mo–W–V hot forging die steels

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International Journal of minerals,Metallurgy and Materials 2017年第10期24卷 1145-1157页

作者： Yuan-ji Shi xiao-chun Wu Jun-wan Li Na min School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The tempering stability of three Fe–Cr–Mo–W–V hot forging die steels(DM, H21, and H13) was investigated through hardness measurements and transmission electron microscopy(TEM) observations. Both dilatometer tests and TEM observations revealed that DM steel has a higher tempering stability than H21 and H13 steels because of its substantial amount of M_2C(M represents metallic element) carbide precipitations. The activation energies of the M_2C carbide precipitation processes in DM, H21, and H13 steels are 236.4, 212.0, and 228.9 kJ/mol, respectively. Furthermore, the results indicated that vanadium atoms both increase the activation energy and affect the evolution of M_2C carbides, resulting in gradual dissolution rather than over-aging during tempering.

关键词： tempering stability hot forging die steels carbide precipitation

毛竹PheTCP19b基因可变剪接体对芽发育的影响

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农业生物技术学报 2025年第1期33卷 43-54页

作者：郝琴申孜闫小玲周敏舒郭小勤浙江农林大学竹子研究院/省部共建亚热带森林培育国家重点实验室

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b基因可变剪接体的表达... 详细信息

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b基因可变剪接体的表达特性及生物学功能，本研究采用RT-PCR技术克隆了毛竹TCP19b基因全长CDS，采用qRT-PCR技术和GUS组织染色分析了可变剪接体的表达量及表达部位，通过亚细胞定位及遗传转化分析了可变剪接体编码蛋白的定位及生物学功能。结果显示，毛竹PheTCP19b基因发生了可变剪接，产生了2种可变剪接体PheTCP19bα和PheTCP19bβ，分别编码346和382个氨基酸，2种可变剪接体都包含保守的bHLH结构域。PheTCP19b与水稻(Oryza sativa) OsTCP19亲缘关系最近。2个可变剪接体的组织特异性表达模式存在一定差异，PheTCP19bα的组织特异性强，而PheTCP19bβ表现出组成型表达特性，油菜素内酯(brassinolide, BR)可诱导2个可变剪接体的表达。2个可变剪接体蛋白均富集在细胞核。PheTCP19bα和PheTCP19bβ均可以将拟南芥(Arabidopsis thaliana) brc1突变体多分枝表型回补到野生型表型。本研究为进一步探讨PheTCP19b基因不同剪接体在芽发育过程中的分子机制提供了基础资料。

关键词：毛竹 TCP转录因子可变剪接(AS) 芽发育油菜素内酯(BR)

Adsorption of boron and its relationship with morphologies of TiC

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Rare Metals 2016年第9期35卷 705-710页

作者： Hai-min Ding xiao-Liang Fan Xin-chun Zhang Ze-You Zheng School of Energy Power and Mechanical Engineering North China Electric Power University

First-principle calculations were performed to study the adsorption of boron and its relationship with the morphologies of Ti *** is found that although the adsorption of boron on all the low-index Ti C crystal planes is thermally favorable,it will be adsorbed more easily by C-terminated {111} and {011} planes,while less possible to be adsorbed by {001}.The study of the formation of B–B clusters indicates that the distribution of boron adatoms on C-terminated（111） and {011} planes will be more uniform,and the diffusion of the adatom further confirms the above *** to the geometry relationship and growth rate of different crystal planes,it is deduced that the adsorption of boron on Ti C will seriously impede the growth of {111} and {011} planes,which can make Ti C grow into hexagonal platelets.

关键词： Ti C Adsorption Surfaces and interfaces First-principle calculations

Homopolypeptide Vesicles Triggered by Side-Chain Hydration

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Chinese Journal of Polymer Science 2022年第12期40卷 1631-1639,I0009页

作者： Xin-Jie Shi Zhen Liu Yang-chun Xie min Xu xiao-Hua He School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200241China School of Physics and Electronic Science Shanghai Key Laboratory of Magnetic ResonanceEast China Normal UniversityShanghai 200241China

The formation of homopolypeptide vesicles and the identification of their self-assembly mechanism have been challenging issues in the field of polymer self-assembly. Using complementary circular dichroism(CD), Fourier transform infrared(FTIR) and low-field nuclear magnetic resonance(LF-NMR) spectroscopies, in this study we show that the higher hydrophilic ability of side-chains is a key factor for the formation of homopolypeptide vesicles from homo poly(Nε-carbobenzoxy-L-lysine)(PZlys), in which the vesicular structures are confirmed by scanning electron microscopy(SEM), transmission electron microscopy(TEM) and atomic force microscopy(AFM) measurements. Poly(γ-benzyl-Lglutamate-co-Nε-carbobenzoxy-L-lysine) [P(BLG-co-Zlys)] containing different molar ratios of BLG to Zlys units with the same peptide backbone as PZlys are used as the controls. The copolypeptides can only form micelles under the same conditions, due to the more hydrophobic nature of their side-chains. These results show that the specific side-chain structure of the polypeptides plays a fundamental role in the self-assembly of homopolypeptides. These findings can be useful to understand how the hydrophilicity of the side chains of amino acid residues on the surface of a protein affects its structures.

关键词： Polypeptide Vesicle Self-assembly Hydrophobic Micelle