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Regioselective C-C bond cleavage/aminocarbonylation cascade under copper catalysis

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Science China Chemistry 2024年第11期67卷 3798-3806页

作者： Qi-Chao Shan Yan Zhao yong Wu hong-Fei Liu Xin-hua Duan Li-Na Guo Department of Chemistry School of Chemistry Energy Research Center of Energy Storage Materials and Devices Ministry of EducationXi'an Jiaotong University State Key Laboratory of Applied Organic Chemistry Lanzhou University

A regioselective C-C bond cleavage/aminocarbonylation cascade is presented. In recent years, tremendous progress has been made in the alkoxyl radical-mediated C-C bond cleavage of unstrained monocarbocycles. In contrast, the deconstruction and functionalization of bicyclic skeletons has been less developed and has mainly focused on the ring expansion process. Inspired by the aromatization-driven C-C bond cleavage, here we demonstrate a ring-opening/aminocarbonylation cascade under copper catalysis, in which the formation of a stable γ-lactam or succinimide skeleton reverses the selectivity of C-C cleavage. Remarkably, the photo and thermal assistance is not required when the succinimide skeleton is formed during the ring opening process. DFT calculations revealed that this unexpected ring-opening process is thermodynamically and kinetically favourable.

关键词： C-C bond cleavage controllable regioselectivity aminocarbonylation bicyclic alkoxy radical

C_0-Semigroup Method of the Density Evolution Equation for M/M/∞ Model

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Journal of Shanghai University(English Edition) 2001年第4期5卷 265-268页

作者： SHI Ding hua, XIONG yong, XU hong College of Sciences, Shanghai University, Shanghai 200436, China College of Sciences Shanghai University Shanghai China

In this paper, the existence, uniqueness, and asymptotic behavior of the solution of the density evolution equation for M/M/∞ model was studied by the semigroup theory of linear operators.

关键词： M/M/∞ model density evolution equation C 0-semigroup

Performance of the walking trail making test in older adults with white matter hyperintensities

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World Journal of Psychiatry 2024年第1期14卷 102-110页

作者： hong-Yi Zhao Zhi-Qiang Zhang yong-hua huang hong Li Fang-Yuan Wei Department of Neurology No.984 Hospital of PLABeijing 100094China Department of Neurology The Seventh Medical Center of PLA General HospitalBeijing 100700China Mental Health Institute of Inner Mongolia Autonomous Region The Third Hospital of Inner Mongolia Autonomous RegionHohhot 010010Inner Mongolia Autonomous RegionChina Department of Neurosurgery No.984 Hospital of PLABeijing 100094China Department of Hand and Foot Surgery Beijing University of Chinese Medicine Third Affiliated HospitalBeijing 100029China Engineering Research Center of Chinese Orthopaedic and Sports Rehabilitation Artificial Intelligent Ministry of EducationBeijing 100029China

BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive *** hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities(WMH).AIM To explore the performance in the WTMT in older people with *** In this single-center,observational study,25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age,gender,and educational level who were undergoing physical examination in our hospital during the same period served as the control *** participants completed the WTMT-A and WTMT-B to obtain their gait parameters,including WTMT-A completion time,WTMT-B completion time,speed,step length,cadence,and stance phase *** matter lesions were scored according to the Fazekas *** neuropsychological assessments were carried out to assess cognitive *** relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation *** Patients with WMH performed significantly worse on the choice reaction test(CRT)(0.51±0.09 s vs 0.44±0.06 s,P=0.007),verbal fluency test(VFT,14.2±2.75 vs 16.65±3.54,P=0.012),and digit symbol substitution test(16.00±2.75 vs 18.40±3.27,P=0.010)than participants in the control *** WMH group also required significantly more time to complete the WTMT-A(93.00±10.76 s vs 70.55±11.28 s,P<0.001)and WTMT-B(109.72±12.26 s vs 82.85±7.90 s,P<0.001).WTMT-A completion time was positively correlated with CRT time(r=0.460,P=0.001),while WTMT-B completion time was negatively correlated with VFT(r=-0.391,P=0.008).On the WTMT-A,only speed was found to statistically differ between the WMH and control groups(0.803±0.096 vs 0.975±0.050 m/s,P<0.001),whereas on the WTMT-B,the WMH group exhibited a sign

关键词： White matter hyperintensities Cognitive dysfunction Motor deficits Gait analysis Trail making test Small vessel disease

Cisplatin-based miRNA delivery strategy inspired by the circCPNE1/miR-330-3p pathway for oral squamous cell carcinoma

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2748-2760页

作者： hua-yang Fan Ming-da Zhao hong-jie Jiang Zhen-wei Yu Yu-jiang Fan Xin-hua Liang Ya-ling Tang yong Sun State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Oral and Maxillofacial Surgery West China Hospital of StomatologySichuan UniversityChengdu 610041China National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610065China State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases&Department of Oral Pathology West China Hospital of StomatologySichuan UniversityChengdu 610041China

Circular RNAs(circRNAs)are ideal biomarkers of oral squamous cell carcinoma(OSCC)because of their highly stable closed-loop structure,and they can act as microRNA(miRNA)sponges to regulate OSCC *** analyzing clinical samples,we identified circCPNE1,a dysregulated circRNA in OSCC,and its expression level was negatively correlated with the clinical stage of OSCC ***-of-function assays revealed the tumor-suppressive effect of circCPNE1,which was then identified as a miR-330-3p ***-330-3p was recognized as a tumor promoter in multiple studies,consistent with our finding that it could promote the proliferation,migration,and invasion of OSCC *** results indicated that selective inhibition of miR-330-3p could be an effective strategy to inhibit OSCC ***,we designed cationic polylysine-cisplatin prodrugs to deliver antagomiR-330-3p(a miRNA inhibitory analog)via electrostatic interactions to form PP@miR nanoparticles(NPs).Paratumoral administration results revealed that PP@miR NPs effectively inhibited subcutaneous tumor progression and achieved partial tumor elimination(2/5),which confirmed the critical role of miR-330-3p in OSCC *** findings provide a new perspective for the development of OSCC treatments.

关键词： Oral squamous cell carcinoma CircRNA MiRNA sponge Antagomir MiRNA delivery Cisplatin-based nanoparticles Drug delivery systems Tumor elimination

Technical and Dosimetric Study of Four Facio-cervical Fields Conformal Radiotherapy for Nasopharyngeal Carcinoma

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Chinese Journal of Biomedical Engineering(English Edition) 2015年第1期24卷 28-32页

作者： WANG Fang-zheng FU Zhen-fu WANG Lei PIAO yong-feng hua yong-hong CHEN Wei-jun XU Min Department of Radiation Oncology Zhejiang Tumor Hospital

Objective: The aim of this study is to establish the methods of four facio-cervical field's conformal radiotherapy(4F-CRT) for nasopharyngeal carcinoma(NPC), and to optimize the methods for clinical practice. Materials and Methods:40 patients with untreated NPC of T1-T4(1997 AJCC Staging System) were rolled into this *** and four facio-cervical fields conform plans were designed for each patient using Pinnacle 8.0 three-dimension treatment planning system(3D-TPS)as follows: 1. Improved plan, four facio-cervical field's conform plan, anterior, posterior facio-cervical and two lateral opposing facio-cervical fields; 2. Conventional plan, two lateral opposing facio-cervical fields delivered to the target in each plan, only with the same dose dose volume histograms(DVHs) of the targets and normal organs, brain stem,spinal cord, parotid glands, and temporal mandibular joints(TMJs) were compared and the dose distribution were evaluated. Results: *** dose distribution of the improved plan could meet the requirements for the target volume. 2. There was not any significant difference in the dose of spinal cord between the two *** mean doses of Dmaxfor brain stem in conventional plan were much lower than those in the improved plan,though both were within safety limits. 3. Compared with the conventional plans, the improved plan significantly decreased the hotspot areas in the target volume and had better parotid glands and temporal mandibular joints sparing effect. Conclusion:Compared with the conventional plan, the improved plan provides satisfactory dose coverage to the tumor volume and better sparing of the parotid gland, TMJs and other normal tissues in external beam radiotherapy of NPC.

关键词： asopharyngeal neoplasms four facio-cervical fields conformal radiotherapy TPS dosimetry

Laser manufacturing of spatial resolution approaching quantum limit

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Light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang hong-hua Fang Zhen-Ze Li Dan Wang hong-Bo Sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing *** manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for *** is,however,suffering from optical diffraction ***,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size of<5 nm is *** underlying physics is that the uncertainty of local atom thermal motion dominates electron excitation,rather than the power density slope of the incident *** show that the colour centre yield in hexagonal boron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to *** a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

Mechanism of local solidification time variations with melt rate during vacuum arc remelting process of 8Cr4Mo4V high-strength steel

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Journal of Iron and Steel Research International 2024年第2期31卷 377-388页

作者： Tao Pan hong-chun Zhu Zhou-hua Jiang hua-bing Li Rui Zhang Hao Feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh *** results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width ***,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium *** melt rate increases,both the molten pool depth and the mushy width *** is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the *** nonlinear increment in sensible heat leads to a nonlinear increase in the mushy *** addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then *** melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time

On traceable iterated line graph and hamiltonian path index

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 239-252页

作者： NIU Zhao-hong XIONG Li-ming YANG Wei-hua School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China School of Mathematics and Statistics Beijing Key Laboratory on MCAACIBeijing Institute of TechnologyBeijing 100081China Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Xiong and Liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥*** this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characterization of G for which L^(n)(G)has a hamiltonian *** applications,we use this characterization to give several upper bounds on the hamiltonian path index of a graph.

关键词： iterated line graph traceable hamiltonian index hamiltonian path index

Atomistic study of inverse size effect induced by interfacial plasticity in pearlitic multi-principal element alloy

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Rare Metals 2024年第7期43卷 3341-3355页

作者： Chen Yang Qiao-Sheng Xia Cun-hong Yin Dong-Peng hua College of Mechanical Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou UniversityGuiyang 550025China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China

Owing to the fine nano-laminated structure,the pearlitic multi-principal element alloy(PMPEA) exhibits excellent mechanical and tribological ***,the incomplete understanding of the size effect of its lamella thickness and the unclear understanding of the plasticity-interface interaction mechanism limit further optimization of *** this study,the FeCoNi/Ni_3Ti interface-mediated plastic deformation behavior in PMPEA and the variation of mechanical and tribological properties with lamella thickness within the nanoscale range using molecular dynamics(MD) simulation were *** results indicate that the mechanical and tribological properties of the PMPEA with lamella thicknesses below 10 nm have a significant inverse size effect,i.e.,the smaller the lamella thickness,the weaker the *** is because the plastic carrier-interface interaction mechanism changes from a strengthening mechanism that hinders dislocations to a weakening mechanism that promotes dislocations with the decreases in the lamella thickness,and the weakening effect becomes more pronounced as the lamella thickness decreases and the number of interfaces *** particular,the deformation behavior of Ni_3Ti lamellae changes from crystal-like to amorphous-like with decreasing ***,in the sample with larger lamella thickness,the occurrence of hierarchical slips in the body-centered cubic(BCC) phase due to the multiprincipal elements effect can better alleviate the stress concentration caused by the dislocation accumulation at the interface,so that the phase interface exhibits outstanding load-bearing *** the dislocation pattern in BCC phase shows a firm high-density cell,which makes the substrate exhibit a stable tribological response.

关键词： Multi-principal element alloy Nano-laminated structure Molecular dynamics simulation Nanoindentation and nanoscratch