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Base-catalyzed Formation of Enamines from β,β-Dicyanostyrene Derivatives with N-Bromosaccharin

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Chemical Research in Chinese Universities 2018年第5期34卷 751-757页

作者： KANG nan chen Zhanguo Key Laboratory of Applied Surface and Colloid Chemistry Ministry of Education Key Laboratory for Macromoleeular Science of Shaanxi ProvinceSchool of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi 'an 710119 R. P China

A new method for the synthesis of functional enamines from β,β-dicyanostyrene derivatives and N-bromosaccharin（NBSA） was developed. In the presence of Na2CO3, the the reaction of β,β-dicyanostyrene derivatives with NBSA can generate the corresponding enamines smoothly in a mixed solvent of dichloromethane and N,N-dimethylformamide（DMF）（volume ratio 1：1） at 50 ℃. The reaction of 14 kinds of β,β-dicyanostyrene derivatives with NBSA was investigated. Screened olefins afforded the corresponding enamines in good to excellent yields（up to 94%）, indicating that the method has a wide adaptability for the substrate. The catalyst used is inexpen- sive and stable for storage. The amino groups of all products in their structures are on the a-position of products, revealing the reaction has an excellent regioselectivity. The possible pathway involving aminobromination of β,βdicyanostyrene derivative with NBSA first and then elimination of HBr process in one pot has been proposed. The structures of all products were confirmed by ^1H NMR, ^13C NMR and HRMS analysis.

关键词： β,β-Dicyanostyrene derivative Functional enamine Sodium carbonate N-Bromosaccharin

Increasing high-temperature fatigue resistance of polysynthetic twinned TiAl single crystal by plastic strain delocalization

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Journal of Materials Science & Technology 2021年第34期93卷 53-59页

作者： Yang chen Yuede Cao Zhixiang Qi guang chen MIT Key Laboratory of Advanced Metallic and Itermetalic Materials Techmology Engineering Research Center of Materials Behavior and Design Ministry of EducotionNanjing University of Science and TechnologyNanjing 210094Chind

Polysynthetic twinned(PST)TiAl single crystal possesses great potentials for high-temperature applications due to its excellent combination of strength,ductility and creep ***,a critical property for high-temperature application of such material involving high-temperature fatigue properties remains ***,the high-temperature high-cycle fatigue performance of PST TiAl single crystal has been *** result shows that PST TiAl single crystal can withstand more than 107 cyclic loadings at 975℃ under a stress amplitude of 270 MPa,which is significantly higher than traditional TiAl *** observations and atomistic simulations indicate that the improvement of fatigue resistance is attributed to the plastic strain delocalization in uniform lamellar structure,and the plastic deformation is well-distributed and sufficient in each *** in theα2 lamella with difficult slippage,a large number of stacking fault structures can be ***{c+a}dislocations inα2 tend to dissociate into a Frank partial with b=1/6,forming a ribbon of I1 fault which ensures the continuity of deformation.

关键词： TiAl Single crystal Fatigue High temperature Strain delocalization

Modular Representations and Coinvariants of the Dihedral Group

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ALGEBRA COLLOQUIUM 2024年第4期31卷 711-720页

作者： chen, Haixian nan, Jizhu Shanxi Univ Sch Math & Stat Taiyuan 030006 Peoples R China Dalian Univ Technol Sch Math Sci Dalian 116024 Liaoning Peoples R China

In this paper, we completely classify a finite number of inequivalent indecomposable modular representations of the dihedral group D-2m in characteristic p, p|2m , and determine that there exists a summand of the grou... 详细信息

关键词： dihedral group modular representation coinvariant regular representation

Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

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Neural Regeneration Research 2025年第2期20卷 548-556页

作者： Zhihui Ren Tian Li Xueer Liu Zelin Zhang Xiaoxuan chen Weiqiang chen Kangsheng Li Jiangtao Sheng Department of Microbiology and Immunology Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular ImmunopathologyShantou University Medical CollegeShantouGuangdong ProvinceChina Department of Neurosurgery First Affiliated Hospital of Shantou University Medical CollegeShantouGuangdong ProvinceChina

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system *** neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types ***-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related ***,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain *** this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from *** found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 *** VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical *** findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological ***,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

关键词： central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents

Exosomes originating from neural stem cells undergoing necroptosis participate in cellular communication by inducing TSC2 upregulation of recipient cells following spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3273-3286页

作者： Shiming Li Jianfeng Li Guoliang chen Tao Lin Penghui Zhang Kuileung Tong Ningning chen Shaoyu Liu Shenzhen Key Laboratory of Bone Tissue Repair and Translational Research Department of Orthopedic SurgeryThe Seventh Affiliated HospitalSun Yat-sen UniversityShenzhenGuangdong ProvinceChina Department of Orthopedic Surgery The First Affiliated Hospital of Jinan UniversityGuangzhouGuangdong ProvinceChina Department of Orthopedics and Traumatology Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Department of Orthopedic Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Department of Orthopedic Surgery The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

We previously demonstrated that inhibiting neural stem cells necroptosis enhances functional recovery after spinal cord *** exosomes are recognized as playing a pivotal role in neural stem cells exocrine function,their precise function in spinal cord injury remains *** investigate the role of exosomes generated following neural stem cells necroptosis after spinal cord injury,we conducted singlecell RNA sequencing and validated that neural stem cells originate from ependymal cells and undergo necroptosis in response to spinal cord ***,we established an in vitro necroptosis model using neural stem cells isolated from embryonic mice aged 16-17 days and extracted *** results showed that necroptosis did not significantly impact the fundamental characteristics or number of *** sequencing of exosomes in necroptosis group identified 108 differentially expressed messenger RNAs,104 long non-coding RNAs,720 circular RNAs,and 14 microRNAs compared with the control *** of a competing endogenous RNA network identified the following hub genes:tuberous sclerosis 2(Tsc2),solute carrier family 16 member 3(Slc16a3),and forkhead box protein P1(Foxp1).Notably,a significant elevation in TSC2 expression was observed in spinal cord tissues following spinal cord ***2-positive cells were localized around SRY-box transcription factor 2-positive cells within the injury ***,in vitro analysis revealed increased TSC2 expression in exosomal receptor cells compared with other *** assessment of cellular communication following spinal cord injury showed that Tsc2 was involved in ependymal cellular communication at 1 and 3 days post-injury through the epidermal growth factor and midkine signaling *** addition,Slc16a3 participated in cellular communication in ependymal cells at 7 days post-injury via the vascular endothelial growth factor and macrophage migration inhibitory factor signaling

关键词： cellular communication competing endogenous RNA exosomes Foxp1 necroptosis neural stem cells Slc16a3 spinal cord injury transcriptome sequencing Tsc2

Surgical management of fungal endophthalmitis resulting from fungal keratitis

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International Journal of Ophthalmology(English edition) 2016年第6期9卷 848-853页

作者： Yan Gao nan chen Xiao-guang Dong Gong-Qiang Yuan Bin Yu Li-Xin Xie Qingdao University Medical College Qingdao 266071Shandong ProvinceChina Qingdao Eye Hospital Shandong Eye InstituteShandongAcademy of Medical SciencesQingdao 266071Shandong ProvinceChina Shandong Eye Hospital Shandong Eye InstituteShandongAcademy of Medical SciencesJinan 250021Shandong ProvinceChina

AIM： To report the fungal organisms, clinical features, surgical treatment strategies, and outcomes of patients with culture-proven exogenous fungal endophthalmitis （EFE） secondary to keratitis, and evaluate the role of surgery in the treatment. METHODS： The clinical records of 27 patients （27 eyes） with culture-proven EFE resulting from fungal keratitis treated at Shandong Eye Institute from January 2007 to January 2015 were retrospectively reviewed. Information about fungal culture results, clinical features, surgical procedures, and final visual acuity was obtained. RESULTS： There were 39 positive culture results from samples of cornea, hypopyon, vitreous and lens capsule, accounting for 56%, 26%, 15% and 2.5%, respectively. Fusarium was identified in 44% （12/27） of the eyes, followed by Aspergillus in 22% （6/27）. Posterior segment infection was involved in 78% （21127） of the patients. The corneal infection was larger than 3 mmx3 mm in 89% （24/ 27） of the patients, and 22% （6/27） of them had the entire cornea, and even the sclera involved. Three eyes had silicone oil tamponade, and two eyes had retinal detachment. Twenty-two eyes （81.5%） underwent penetrating keratoplasty （PKP）, and over half of them （545%） were operated within 3d from the onset of antifungal therapy. Fourteen eyes （52%） underwent intracameral antifungal drug injection, and three of them required repeated injections. Fifteen eyes （55.6%） underwent pars plana vitrectomy （PPV）. The rate of the eyes undergoing PPV as the initial surgical procedure was 60% （9/15）, lower than 77% in PKP. Intravitreal injection was given in 59% of the eyes （16/27）, and 75% of them required repeated injections. The final visual acuity was 20/100 or better in 37% of the eyes, and better than counting fingers in 55.6% of the eyes. Five eyes （18.5%） were eviscerated. In the two eyes with concurrent retinal detachment, one achieved retinal reattachment, and the other was eviscerated. In the three eyes with silicone oil ta

关键词： exogenous fungal endophthalmitis fungalkeratitis penetrating keratoplasty vitrectomy antifungaltherapy retinal detachment surgery

Performance of Flexible Warp Knitting Metal Mesh with Notch

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Journal of Donghua University(English Edition) 2014年第5期31卷 582-588页

作者： SHAO guang-wei JIANG Jin-hua PAN Qiao-ling LIU Yuan-yuan chen nan-liang College of Textiles Donghua University Shanghai 201620 China Engineering Research Center of Technical Textiles Ministry of Education Donghua University Shanghai 201620 China Research Institute of Donghua University Shanghai 201620 China

Three different kinds of notch involving single edge notch （ SEN）, double edge notch （ DEN ） and central notch （ CEN ） were preset in flexible warp knitting metal mesh, and the tensile properties of notch samples were tested. Three kinds of notch samples＇ sensitivity were investigated through different notch lengths. Then failure process and tensile properties were contrasted and analyzed between intact and notch samples. Experiment and analysis results showed that positive Poisson＇s ratio effect gave rise to obvious waist binding and special inverted triangle loading area. All samples were sensitive to three kinds of notches. And notch sensitivity was closely related to notch form and notch length. The notch procession obviously deteriorated the mechanical properties of flexible warp knitting metal mesh. Sample with different notch lengths and breakage locations determined different tensile strengths that sample could bear. The fitting function of waist binding track satisfied the parabolic equation.

关键词： warp knitting metal mesh notch sensitivity tensilestrength preset notch stainless steel wire

Photoinduced Weyl semimetal phase and anomalous Hall effect in a three-dimensional topological insulator

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Chinese Physics B 2021年第11期30卷 94-101页

作者： Meng-nan chen Wen-Chao chen School of Science Hangzhou Dianzi UniversityHangzhou 310018China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310018China

Motivated by the fact that Weyl fermions can emerge in a three-dimensional topological insulator on breaking either time-reversal or inversion symmetries,we propose that a topological quantum phase transition to a Weyl semimetal phase occurs under the off-resonant circularly polarized light,in a three-dimensional topological insulator,when the intensity of the incident light exceeds a critical *** circularly polarized light effectively generates a Zeeman exchange field and a renormalized Dirac mass,which are highly *** phase transition can be exactly characterized by the first Chern number.A tunable anomalous Hall conductivity emerges,which is fully determined by the location of the Weyl nodes in momentum space,even in the doping *** predictions are experimentally realizable through pump-probe angle-resolved photoemission spectroscopy and raise a new way for realizing Weyl semimetals and quantum anomalous Hall effects.

关键词： Floquet theory Weyl semimetal topological phase transition Hall conductivity

Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise

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Neural Regeneration Research 2025年第3期20卷 836-844页

作者： Do-Hun Lee Dan Cao Younghye Moon chen chen Nai-Kui Liu Xiao-Ming Xu Wei Wu Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteIndiana University School of MedicineIndianapolisINUSA Department of Neurological Surgery Indiana University School of MedicineIndianapolisINUSA Department of Neuroscience Baylor College of MedicineHoustonTXUSA

Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.

关键词： behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise