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Synthesis and Crystal Structure of a New N-alkylated Azacrown Ligand

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Chinese Journal of Structural Chemistry 1997年第3期16卷 195-199页

作者： xu xin-you LUO Qin-Hui NI Shi-Sheng xu Ji-De MENG Nan(Coordination Chemistry Institute, State Key Laboratory ofCoordination Chemistry Nanjing University, Nanjing 210008)ZHOU Xiang-Ge ZHOU Zhong-Yuan(Chengdu Institute of Organic Chemistry, The Chinese 南京大学配位化学所配位化学国家重点实验室江苏南京中科院成都有机化学所四川成都

A new pendant arms macrocyclic ligand, N, N'-bis(2-cyanoethyl)-3,4: 9, 10-dibenzo-1, 12-diaza-5, 8-dioxacyclopentadecane (L), was synthesized in goodyield (93% ) by alkylating 3, 4: 9, 10-dibenzo-1, 12-diaza-5, 8-dioxacyclopentadecane(L') with acrylonitrile. Its crystal structure has been determined by X-ray *** ligand crystallizes in the orthorhombic system, space group Pbca, a=18. 143 (3),b=11. 206(2), c=22. 274(5)A, V=4528(2)A3, Mr=418. 55, Z= 8, F(000)=1792, Dc= 1. 228 gcm-3, T= 293K, μ= 7. 9 cm-1, final R=0.044 and Rw=0.067(w=1/(σ2 (F) + 0. 0005F2 ) ) based on 2291 independent reflections with F> 4. 0σ(F). The two benzene rings of the macrocyclic ligand are not in the same plane, andthe dihedral angle between them is 73. 6°, the molecule is in a folded state.

关键词： synthesis crystal structure N-alkylated ligand azacrown

Single-atom catalysis for advanced oxidation and reduction systems in water decontamination

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Rare Metals 2024年第8期43卷 3576-3606页

作者： Jie Teng Jin-Hui xu Wen-xin Sun xue-Feng Liu Xia xu Guo-Shuai Liu School of Urban Construction Changzhou UniversityChangzhou 213164China School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Water scarcity is an escalating global crisis,posing a severe threat to populations ***,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant *** this regard,single-atom catalysis(SACs) has emerged as a catalyst of scientific progress in water purification and treatment methodologies during recent *** exhibit exceptional catalytic activity,selectivity and stability,due to their near-perfect atom utilization,highly unsaturated coordination environment and uniform reaction ***,a comprehensive and critical review encompassing the successful integration of SACs into water purification processes needs to be *** review aims to accentuate recent trends by presenting the synthesis,structure,and environment and energy application-relevant properties of *** results show that a comprehensive and multi-perspective summary of the advantages of SACs in environmental remediation can have significant benefits,such as fast kinetics,costeffectiveness,*** oxidation and reduction processes of SACs and functional SACs materials in water purification were ***,the last section is devoted to the current research gaps and further perspectives on the application of SACs in water treatment,which are summarized and analyzed.

关键词： Single-atom catalysis Water treatment Oxidation Reduction

Exosomes from umbilical cord mesenchymal stromal cells promote the collagen production of fibroblasts from pelvic organ prolapse

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World Journal of Stem Cells 2024年第6期16卷 708-727页

作者： Lei-Mei xu xin-xin Yu Ning Zhang Yi-Song Chen Department of Gynecology Obstetrics and Gynecology Hospital of Fudan UniversityShanghai 200011China Department of Gynecology Shanghai Key Laboratory of Female Reproductive Endocrine-related DiseasesShanghai 200011China

BACKGROUND Pelvic organ prolapse(POP)involves pelvic organ herniation into the vagina due to pelvic floor tissue laxity,and vaginal structure is an essential *** POP,the vaginal walls exhibit abnormal collagen distribution and decreased fibroblast levels and *** intricate etiology of POP and the prohibition of trans-vaginal meshes in pelvic reconstruction surgery present challenges in targeted therapy *** umbilical cord mesenchymal stromal cells(hucMSCs)present limitations,but their exosomes(hucMSC-Exo)are promising therapeutic tools for promoting fibroblast proliferation and extracellular matrix *** inflammation in POP group fibroblasts,stimulated primary fibroblast growth,and elevated collagen I(Col1)production in ***-throughput RNA-seq of fibroblasts treated with hucMSC-Exo and miRNA sequencing of hucMSC-Exo revealed that abundant exosomal miRNAs downregulated matrix metalloproteinase 11(MMP11)*** HucMSC-Exo normalized the growth and function of primary fibroblasts from patients with POP by promoting cell growth and Col1 expression in *** miRNAs in hucMSC-Exo targeted and downregulated MMP11 ***-Exo-based therapy may be ideal for safely and effectively treating POP.

关键词： Pelvic organ prolapse Exosomes Fibroblasts Human umbilical cord mesenchymal stromal cells Extracellular matrix Collagen I

Direct-acting antivirals failed to reduce the incidence of hepatocellular carcinoma occurrence in hepatitis C virus associated cirrhosis: A real-world study

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World Journal of Hepatology 2024年第1期16卷 41-53页

作者： xue-Mei Tao Ming-Hui Zeng you-Fei Zhao Jia-xin Han Yu-Qiang Mi Liang xu Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Department of Hepatology Tianjin Research Institute of Liver DiseasesTianjin 300192China

BACKGROUND Direct-acting antivirals(DAAs)revolutionized the treatment of chronic hepatitis C virus(HCV)-associated disease achieving high rates of sustained virological response(SVR).However,whether DAAs can reduce the occurrence of hepatocellular carcinoma(HCC)in patients with HCV-associated cirrhosis who are at high risk have not been *** To investigate the effect of DAAs on the occurrence of HCC in patients with HCVassociated cirrhosis after achieving *** Of 427 inpatients with HCV-associated cirrhosis were enrolled in Tianjin Second People's Hospital from January 2014 to April 2020.118 patients weren’t received antiviral treatment with any reasons named non-antiviral treatment group,and 236 patients obtained from the 309 DAAs treatment patients according to the propensity score matching named DAAs treatment *** information and laboratory data were collected from baseline and the following ***-Meier curve and Log-Rank test were used to compare the incidence and cumulative incidence of HCC between the two *** proportional risk regression was used to re-evaluate the risk factors for *** HCC incidence was 4.68/100PY(95%CI,3.09-6.81)in the DAAs treatment group,while it was 3.00/100PY(95%CI,1.50-5.37)in the non-antiviral treatment group,and the relative risk was 1.82(95%CI,0.93-3.53,P>0.05).The incidence of HCC at 12,24,36 and 48 months was 3.39%,6.36%,8.47%and 10.17%in the DAAs treatment group,and it was 0%,0%,3.39%and 9.32%in the non-antiviral treatment group,***>58[hazard ratio(HR)=1.089;95%CI,1.033-1.147;P=0.002]and liver stiffness measurement>27.85 kPa(HR=1.043;95%CI,1.022-1.065;P=0.000)were risk factors for HCC in all patients(n=427),and DAAs treatment didn’t show protective *** DAAs treatment seems failed to reduce the incidence of HCC occurrence in HCV-associated cirrhosis in 48 months,and even increased the incidence of HCC in 36 months.

关键词： Direct-acting antivirals Sustained viral response Cirrhosis Hepatocellular carcinoma Risk factor

Nickel-catalyzed carbonylative four-component 1,4-dicarbofunctionalization of 1,3-enynes

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Science China Chemistry 2024年第6期67卷 2029-2038页

作者： Yan Zhao Qi-Chao Shan Hong xin Pin Gao xu Yang xin-Hua Duan Li-Na Guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy StorageMaterials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China

An efficient Ni-catalyzed four-component 1,4-carbocarbonylation of 1,3-enynes with activated alkyl halides and arylboronic acids under atmospheric pressure of CO is *** tuning the electronic and steric effects of alkyl radicals,both electronrich and electron-deficient 1,3-enynes were compatible with this *** protocol features mild conditions,broad substrate scope,excellent functional group compatibility and facile gram-scale synthesis,providing a practical approach to the quaternary carbon center-containing allenyl *** study revealed that the acyl-NiIIspecies plays an important role in both the coupling and the alkyl radical generation processes.

关键词： Ni catalysis four-component 1 4-carbocarbonylation 1 3-enynes

Wind-sand flow simulation and radius optimization of highway embankment under different vertical curve radius

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Journal of Mountain Science 2024年第8期21卷 2533-2546页

作者： LI Liangying LI Qi WANG xu xin Guowei WANG Zhenqiang School of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius for reducing the risk of sand *** this study,three-dimensional models of desert highway embankments with different vertical curve radii were constructed,and Fluent software was used to simulate the wind-sand flow field and sand accumulation distribution of vertical curve *** results show that:(1)Along the direction of the road,the concave and the convex vertical curve embankments have the effect of collecting and diverging the wind-sand flow,*** the radius of the concave vertical curve is 3000 m,5000 m,8000 m,10000 m and 20000 m,the wind velocity in the middle of the vertical curve is 31.76%,22.58%,10.78%,10.53%and 10.44%,higher than that at both *** the radius of the convex vertical curve is 6500 m,8000 m,10000 m,20000 m and 30000 m,the wind velocity at both ends of the vertical curve is 14.06%,9.99%,6.14%,3.22%and 2.41%,higher than that in the *** diversion effect also decreases with the increase of the radius.(2)The conductivity of the concave and convex vertical curve embankments with different radii is greater than 1,which is the sediment transport *** conductivity increases with the increase of radius and gradually tends to be *** the radius of the concave and convex vertical curves reaches 8000 m and 20000 m respectively,the phenomenon of sand accumulation is no longer *** the same radius condition,the concave vertical curve embankment is more prone to sand accumulation than the convex one.(3)Considering the strength of the collection and diversion of the vertical curve embankment with different radii,and the sand accumulation of the vertical curve embankment in the desert section of Wuma Expressway,the radius of the concave vertical curve is not less than 8000 m,and the r

关键词： Highway engineering Vertical curve Numerical simulation Embankment wind-sand flow Radius optimization

Research progress on intelligent operation and maintenance of bridges

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 173-187页

作者： Wanshui Han Gan Yang Shizhi Chen Kai Zhou xin xu School of Highway Chang'an UniversityXi'an 710064China

In the context of the increasing scale of bridges and the increasing service life of bridges,it is very important to carry out efficient,accurate and intelligent bridge operation and *** recent years,advanced equipment,technology and intelligent algorithms have developed *** is necessary to apply advanced equipment and algorithms to bridge operation and maintenance business to facilitate the digitalization and intelligence of bridge operation and *** grasp the research progress on the bridge intelligent operation and maintenance,this paper summarizes the research progress in recent years from the aspects of intelligent detection equipment and technology,intelligent monitoring equipment and technology,intelligent data analysis,intelligent evaluation and early warning,and intelligent repair and *** to the review,more and more smart devices have been used to replace human beings to detect dangerous and hidden bridge *** the same time,image processing,radar and other technologies have been used to analyze component damage more objectively and *** solve the shortcomings of traditional sensors such as short life and low robustness,more non-contact measurement methods have been *** have proposed various intelligent algorithms to process the massive amount of bridge health monitoring data to improve the quality of the *** achieve the rapid perception of bridge status and timely early warning of structural abnormalities,different from traditional theoretical calculations,scholars have tried to use data-driven methods to intelligently evaluate and early warning of bridge structural *** terms of intelligent repair and maintenance,more intelligent algorithms have been used to optimize structural maintenance strategies and determine the best maintenance time by integrating multisource heterogeneous *** these provide strong support for the automation,digitization and intelligence o

关键词： Bridge engineering Bridge intelligent operation and maintenance Intelligent equipment Technology and algorithms

Improving the value of molecular testing:current status and opportunities in colorectal cancer precision medicine

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Cancer Biology & Medicine 2024年第1期21卷 21-28页

作者： Haiyun Li Linwei Guo Chenchen Wang xin Hu Ye xu Department of Colorectal Surgery Fudan University Shanghai Cancer CenterShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China Department of Gastrointestinal Medical Oncology Fudan University Shanghai Cancer CenterShanghai 200032China Precision Cancer Medical Center Affiliated with Fudan University Shanghai Cancer Center Shanghai 201315China

Colorectal cancer(CRC)is the second leading cause of cancer-related deaths *** radical resection with adjuvant chemotherapy remains the primary treatment choice for CRC,but the 5-year postoperative survival rate is only approximately 60%,and approximately one-third of patients with CRC experience recurrence within 2 years of ***,the transformation of high-throughput sequencing has accelerated the development of precision *** example,KRAS mutations indicate resistance to anti-epidermal growth factor receptor(EGFR)-targeted therapies in ***,molecular-guided individualized therapy has brought new promise in major clinical areas and challenges,such as novel biomarkers predicting sensitivity and resistance to immunotherapy for microsatellite stable(MSS)CRC.

关键词： cancer chemotherapy colorectal

Effect of proppant sizes and injection modes on proppant transportation and distribution in the tortuous fracture model

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Particuology 2024年第1期84卷 261-280页

作者： Jun Li xu Han Siyuan He Mingyi Wu xin Huang Nianyin Li State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China Chongqing Industry Polytechnic College Chongqing401120China Sichuan Particles Energy and Technology Co. LtdChengdu611630China Engineering Technology Research Institute of PetroChina Southwest Oil and Gas Field Company Chengdu610017China

Particle-fluid transport and placement mechanism in tortuous fracture played a crucial role in uncon-ventional ***,most studies focused on mono-size proppant with fluid transport pro-cesses in tortuous ***,the mixture-size proppant with fluid movement mechanism in tortuous fracture was still ***,this study designed and applied a series of experiments with a physical analog model of a tortuous fracture with 120°and 90°-angled bends and combined high-speed camera-based *** experimental system was used to track different-mixture-sized proppant particle motion trajectories for a series of proppant injection schemes;The following conclu-sions were drawn from this study:*** pile-up processes mechanism in all investigated schemes were similar and could be reduced to four main *** packing structure at both sides of the fracture wall had different variation rates,which were controlled by the mix ratio(change from 1∶1-1∶5)of proppant *** new packing patterns,such as Zebra Stripe,had occurred,controlled by the different proppant injection ***-sized mono-proppant(30/50 mesh)had the highest transport efficiency in the tortuous fracture,followed by the mixed-sized multi-proppant(10/20 mesh:30/50 mesh),large-sized proppant(10/20 mesh)was the *** optimized alternating in-jection mode was recommended as injecting small-sized proppant first(30/50 mesh)and followed by mixed-sized multi-proppant(10/20 mesh:30/50 mesh),which could contribute to obtaining the optimal both proppant packing height and travel distance in tortuous *** correlations were devel-oped for predicting the proppant packing height and transportation distance.

关键词： Tortuous fracture model Mixed-sized proppant Multi-sized proppant injection mode Proppant motion and distribution Packing mechanism