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Preparation of nucleoside-pyridine hybrids and pyridine attached acylureas from an unexpected uracil ring-opening and pyridine ring-forming sequence

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Chinese Chemical Letters 2009年第10期20卷 1161-1165页

作者： xue sen Fan Xia wang Xin Ying Zhang Dong Feng Ying Ying Qu School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

Novel pyrimidine nucleoside-3,5-dicyanopyridine hybrids （4） or pyridine attached acylureas （5） were selectively and efficiently prepared from the reaction of 2′-deoxyuddin-5-yl-methylene malononitrile （1）, malononitrile （2） and thiophenol （3） or from an unexpected uracil ring-opening and pyddine ring-forming sequence via the reaction of 1 and 3. It is the first time such a sequence has ever been reported.

关键词： Pyrimidine nucleoside Pyridine Acylureas Ring-opening and -forming reaction

A novel synthesis of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction in ionic liquid

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Chinese Chemical Letters 2008年第2期19卷 153-156页

作者： Xin Ying Zhang Xiao Yan Li xue sen Fan Xia wang Jian Ji wang Gui Rong Qu School of Chemical and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 PR China

An efficient and novel procedure for the preparation of pyrazolo[3,4-b]pyridine derivatives through multi-component reaction of aldehyde, 5-amino-3-methyl-1-phenylpyrazole and malononitrile or cyanoacetate in [bmim][BF4] is described in this paper. Advantages of the method presented here include mild conditions, high yields together with a green nature and ease of recovery and reuse of the reaction medium.

关键词： Pyrazolo[3,4-b]pyridine Multi-component reaction Ionic liquid

Multiple unpinned Dirac points in group-Va single-layers with phosphorene structure

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npj Computational Materials 2016年第1期2卷 142-148页

作者： Yunhao Lu Di Zhou Guoqing Chang Shan Guan Weiguang Chen Yinzhu Jiang Jianzhong Jiang xue-sen wang Shengyuan A Yang Yuan Ping Feng Yoshiyuki Kawazoe Hsin Lin School of Materials Science and Engineering Zhejiang UniversityHangzhouChina State Key Laboratory of Silicon Materials Zhejiang UniversityHangzhouChina Centre for Advanced 2D Materials and Graphene Research Centre National University of SingaporeSingaporeSingapore Department of Physics National University of SingaporeSingaporeSingapore Research Laboratory for Quantum Materials Singapore University of Technology and DesignSingaporeSingapore College of Physics and Electronic Engineering Zhengzhou Normal UniversityZhengzhouChina New Industry Creation Hatchery Center Tohuku UniversitySendaiJapan Institute of Thermophysics Siberian Branch of Russian Academy of SciencesNovosibirskRussia

Emergent Dirac fermion states underlie many intriguing properties of graphene,and the search for them constitutes one strong motivation to explore two-dimensional(2D)allotropes of other ***,the ultrathin layers of black phosphorous,has been a subject of intense investigations recently,and it was found that other group-Va elements could also form 2D layers with similar puckered lattice ***,by a close examination of their electronic band structure evolution,we discover two types of Dirac fermion states emerging in the low-energy *** pair of(type-I)Dirac points is sitting on high-symmetry lines,while two pairs of(type-II)Dirac points are located at generic k-points,with different anisotropic dispersions determined by the reduced symmetries at their *** fully-unpinned(type-II)2D Dirac points are discovered for the first *** the absence of spin-orbit coupling(SOC),we find that each Dirac node is protected by the sublattice symmetry from gap opening,which is in turn ensured by any one of three point group *** SOC generally gaps the Dirac nodes,and for the type-I case,this drives the system into a quantum spin Hall insulator *** suggest possible ways to realise the unpinned Dirac points in strained phosphorene.

关键词： structure spectrum Dirac

Electron-beam-induced degradation of halide-perovskite-related semiconductor nanomaterials

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Chinese Optics Letters 2021年第3期19卷 8-12页

作者： Zhiya Dang Yuqing Luo xue-sen wang Muhammad Imran Pingqi Gao School of Materials Sun Yat-sen UniversityGuangzhou 510006China Department of Physics National University of SingaporeSingapore 117551Singapore Department of Nanochemistry Istituto Italiano di TecnologiaVia Morego 30Genova 16163Italy

The instability of lead halide perovskites in various application-related conditions is a key challenge to be resolved. We investigated the formation of metal nanoparticles during transmission electron microscopy(TEM) imaging of perovskite-related metal halide compounds. The metal nanoparticle formation on these materials originates from stimulated desorption of halogen under electron beams and subsequent aggregation of metal atoms. Based on shared mechanisms,the TEM-based degradation test can help to evaluate the material stability against light irradiation.

关键词： halide perovskite TEM degradation electronic transition stimulated desorption

Unconventional Ge Quantum Structures Formation on Si(001)

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Unconventional Ge Quantum Structures Formation on Si(001)

Mimicking aneurysm in a patient with chronic occlusion of the left middle cerebral artery

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作者： xue-sen wang Department of Physics, Hong Kong University of Science and Technology-Clear Water Bay, Kowloon, Hong Kong, China

The functions of quantum dots are closely related to their geometric properties (e.g., size, shape and elemental distribution). Unconventional quantum structures of Ge (or Ge/Si), obtained by alternative Ge/Si physical vapor deposition (PVD) on planar Si(001) and by Ge deposition on nanoscale-patterned Si(001). have been analyzed with scanning tunneling microscopy. By proper controlling the amount of deposition of Ge

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World Journal of Clinical Cases 2025年第3期13卷 20-23页

作者： xue-Jian wang Department of Neurosurgery Affiliated Hospital 2 of Nantong UniversityNantong 226000Jiangsu ProvinceChina

The chronic occlusion of intracranial arteries generally has no or mild clinical symptoms,and the clinical symptoms of acute cerebral artery occlusion are mostly manifested as severe cerebral infarction symptoms,which often make early diagnosis difficult,thus losing the best treatment *** cerebral infarction occurs,the consequences are difficult to *** is also an important reason for the high misdiagnosis rate and mortality of this *** this paper,the characteristics of the disease were analyzed to provide clinical reference.

关键词： Chronic occlusion Misdiagnose Arterial occlusion Middle cerebral artery occlusion Aneurysm

EZH2-dependent myelination following sciatic nerve injury

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Neural Regeneration Research 2025年第8期20卷 2382-2394页

作者： Hui Zhu Li Mu Xi Xu Tianyi Huang Ying wang Siyuan Xu Yiting wang Wencong wang Zhiping wang Hongkui wang Chengbin xue Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityKey Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Medical School of Nantong University NantongJiangsu ProvinceChina Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Rehabilitation Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Critical Care Medicine Nantong Fourth People’s HospitalNantongJiangsu ProvinceChina

Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve ***,the gene regulatory network of regenerated myelin differs from that of native *** of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in *** further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were *** results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain *** highlights the crucial role of Ezh2 in initiating Schwann cell ***,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type *** suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and *** conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve *** EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

关键词： demyelination EZH2 myelination peripheral nerve injury PRC2 remyelination Schwann cells sciatic nerve crush sciatic nerve transection

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li Yan wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Oxygen vacancy Hydrocarbon production Reaction mechanism

The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi Li Jing xue Yuejia Ma Ke Ye xue Zhao Fangliang Ge Feifei Zheng Lulu Liu Xu Gao Dayong wang Qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation