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可溶液加工的聚(多金属氧簇降冰片烯)和聚(己酸降冰片烯)嵌段和无规共聚物的合成及催化功能的研究

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高分子学报 2017年第7期27卷 1159-1168页

作者：成恰苗文科颜雨坤王维南开大学化学学院功能高分子材料教育部重点实验室高分子化学研究所天津300071 天津化学化工协同创新中心南开大学天津300071

将一种可有机功能化的Wells-Dawson POM与降冰片烯相连接,制备了多金属氧簇降冰片烯单体.再利用活性可控的开环易位聚合方法(ROMP),在Grubbs 3^(rd)催化剂的作用下,合成了聚(多金属氧簇降冰片烯)-聚(己酸降冰片烯)的杂化嵌段和无规共聚... 详细信息

将一种可有机功能化的Wells-Dawson POM与降冰片烯相连接,制备了多金属氧簇降冰片烯单体.再利用活性可控的开环易位聚合方法(ROMP),在Grubbs 3^(rd)催化剂的作用下,合成了聚(多金属氧簇降冰片烯)-聚(己酸降冰片烯)的杂化嵌段和无规共聚物(H-CPs),分别简写为Poly(POM)_m-b-Poly(COOH)_n和Poly(POM)_m-r-Poly(COOH)_n.采用~1H-NMR、^(31)P-NMR和FTIR等方法对共聚物结构进行表征,确认我们成功地合成了由共价键连接这2种单体形成的H-CPs.最后,利用带有光散射和红外探测器的凝胶渗透色谱(SEC)测定聚合物的绝对分子量和分子量分布,证明所得到的H-CPs不仅分子量可控,而且分子量分布系数较窄.最后,研究了H-CPs催化氧化四氢噻吩(THT)成环丁亚砜(THTO)反应,结果表明,相比于聚(多金属氧簇)的均聚物(Poly(POM)),H-CPs的催化活性有所下降,原因是POM催化剂含量较低以及H-CPs在催化介质中溶解性的差异.

关键词：多金属氧簇聚(多金属氧簇) 共聚物 ROMP 催化性能

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong miao Michael S.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan miao Li Zhao Yajun Zhang Zhe Yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng Cai Shengjun miao Yuan Li Yu Wang key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Electrocatalytic nitrite reduction to ammonia on isolated bismuth alloyed ruthenium

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Journal of Energy Chemistry 2025年第1期100卷 369-376页

作者： Shiyao Shang Fuzhou Wang Zeyi Sun Chaofan Qiang ke Chu School of Materials Science and Engineering Lanzhou Jiaotong University

Electrochemical reduction of NO2-to NH3（NO2-RR） is recognized as an appealing approach for achieving renewable NH3synthesis and waste ***,we report isolated Bi alloyed Ru （Bi1Ru） as an efficient NO2-RR *** calculations and in situ electrochemical measurements reveal the creation of Bi1-Ru dual sites which can remarkably promote NO2-activation and suppress proton adsorption,while accelerating the NO2-RR protonation energetics to render a high NO2--to-NH3conversion ***,Bi1Ru assembled in a flow cell delivers an NH3yield rate of 1901.4μmol h-1cm-2and an NH3-Faradaic efficiency of 94.3%at an industrial-level current density of 324.3 mA *** study offers new perspectives for designing and constructing p-block single-atom alloys as robust and high-current-density NO2-RR catalysts toward the ammonia electrosynthesis.

关键词： Ammonia

Interaction of major facilitator superfamily domain containing 2A with the blood-brain barrier

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Neural Regeneration Research 2025年第8期20卷 2133-2152页

作者： Yilun Ma Taiwei Dong Fei Luan Juanjuan Yang Feng miao Peifeng Wei College of Pharmacy and First Clinical Medical College Shaanxi University of Chinese MedicineXianyangShaanxi ProvinceChina National Drug Clinical Trial Agency The Second Affiliated Hospital of Shaanxi University of Chinese Medicine/Xixian New District Central HospitalXi′anShaanxi ProvinceChina

The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly *** major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier *** plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain ***,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain *** paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier *** comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to *** will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic *** addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier lea

关键词： blood-brain barrier(BBB) caveolin-1 central nervous system docosahexaenoic acid endothelial cells lysophosphatidylcholine major facilitator superfamily domain containing 2A(MFSD2A) transcytosis

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可验证的安全内积计算协议的设计与实现

通信技术 2016年第10期49卷 1369-1374页

作者：冉鹏张文科杨浩淼电子科技大学计算机科学与工程学院四川成都611731 中电集团30所保密通信重点实验室四川成都610041

安全多方计算旨在解决一组互不信任的参与方之间隐私保护的协同计算问题。自姚期智从1982年提出以来,随着云计算、电子商务技术的发展,安全多方计算得到了更加广泛的研究及应用。余弦相似性是用于度量两个样本点之间相似度的有效方法,... 详细信息

安全多方计算旨在解决一组互不信任的参与方之间隐私保护的协同计算问题。自姚期智从1982年提出以来,随着云计算、电子商务技术的发展,安全多方计算得到了更加广泛的研究及应用。余弦相似性是用于度量两个样本点之间相似度的有效方法,且广泛应用于数据挖掘、神经网络和机器学习等领域。目前存在的大多数安全多方计算研究都忽略了用户输入和结果的验证过程,都假设各参与方是诚实地执行协议。为了弥补这一块的缺陷,设计了一种可验证的安全内积计算的协议,并证实了此协议会更加安全。

关键词：安全内积计算余弦相似性隐私保护可验证

Inspires effective alternatives to backpropagation:predictive coding helps understand and build learning

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Neural Regeneration Research 2025年第11期20卷 3215-3216页

作者： Zhenghua Xu miao Yu Yuhang Song School of Health Sciences and Biomedical Engineering Hebei University of TechnologyTianjinChina Department of Computer Science University of OxfordOxfordUK

Artificial neural networks are capable of machine learning by simulating the hiera rchical structure of the human *** enable learning by brain and machine,it is essential to accurately identify and correct the prediction errors,referred to as credit assignment(Lillicrap et al.,2020).It is critical to develop artificial intelligence by understanding how the brain deals with credit assignment in neuroscience.

关键词： assignment learning enable

Targeting TrkB–PSD-95 coupling to mitigate neurological disorders

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin Yang Yu-wen Alvin Huang John Marshall Department of Molecular Biology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for Translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

Tropomyosin receptor kinase B(TrkB)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic TrkB resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with TrkB enhances phospholipase Cγ-Ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss TrkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of TrkB signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with TrkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated TrkB.T1 *** TrkB agonists and antibodies that activate TrkB are being intensively investigated,they cannot distinguish the multiple human TrkB splicing isoforms or cell type-specific *** TrkB–postsynaptic density protein-95 coupling provides an alternative approach to specifically boost TrkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity TrkB