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Efficient Synthesis of Dicycloalkenopyridines:One-pot Multicomponent Condensation of Aldehydes with Cyclic Ketones

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Chemical Research in Chinese Universities 2009年第5期25卷 657-661页

作者： CAI Xi-mei wang qi-fang yan chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

Under microwave irradiation, the one-pot multicomponent condensation reaction of three moles of aromatic aldehydes with two moles of cyclic ketones having free a,a＇-methylene positions such as cyclopentanone or cyclohexanone in the presence of ammonium acetate and acetic acid afforded dicycloalkenopyridines with two a-arylidene groups in high yields. Under the similar reaction condition, the reaction of aromatic aldehydes with 1-tetralone having only one a-methylene position alternatively resulted in 10-aryl-2,3：5,6-dibenzoacridines.

关键词： Pyridine Acridine Microwave irradiation Aromatic aldehyde Cyclic ketone Aldol condensation

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： fang-qian wang Yin Zhang Wei-Wei wang Mei-qian Fu Hong-Bing Mo Wei-Dong Yu chao Liu Jun yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Likelihood-based modified Kalman filter for estimating vehicle lateral states with random measurement delay

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Science China Technological Sciences 2025年第3期68卷 314-322页

作者： chao yanG Ruixin ZHANG Weida wang Yuhang ZHANG Jiayi fang qi wang Shouwen YAO School of Mechanical Engineering Beijing Institute of Technology Chongqing Innovation Center Beijing Institute of Technology

Accurate lateral state estimation is crucial for ensuring the stability and safety of vehicles. The Kalman filter is widely utilized to estimate the lateral state of vehicles. However, vehicle state measurement suffers from inherent time delays and model discrepancies. The existence of fractional and random delays necessitates long sampling periods for the inputs of the Kalman filter,leading to update mismatch and deterioration of the accuracy of the estimation. This situation poses a threat to driving *** addition, the tire cornering stiffness, a critical model parameter, exhibits nonlinear and dynamic variations that cannot be measured in real time. This inherent variability significantly affects the accuracy of lateral state estimation. Considering internal and external uncertainties, an observer framework for vehicle lateral state estimation based on the Kalman filter was designed in this work. First, a modified delayed Kalman filter method that considers the random fractional delays was developed. The relationship correlation between the delayed measurement and the prior state was constructed based on a likelihood ***, the tire cornering stiffness was estimated online by an algorithm based on recursive least squares. This parameter was used to dynamically adjust the vehicle model for the Kalman filter. Finally, two simulations and a real vehicle experiment were performed to verify the effectiveness of the proposed method. In particular, the root mean squared error(RMSE) of the slip angle decreased by 30.70%, and that of the yaw rate decreased by 61.03% in the double lane change scenario. Actual vehicle experiments demonstrated that the algorithm can be effectively applied in real situations.

关键词： measurement delay Kalman filter parameter identification likelihood estimation

Elucidating oxygen evolution and reduction mechanisms in nitrogen-doped carbon-based photocatalysts

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Chinese Chemical Letters 2025年第2期36卷 224-229页

作者： yan wang Jiaqi Zhang Xiaofeng Wu Sibo wang Masakazu Anpo Yuanxing fang State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University Sino-UK International Joint Laboratory on Photocatalysis for Clean Energy and Advanced Chemicals & Materials Fuzhou University Department of Chemistry and Materials Innovation Factory University of Liverpool

Solar-induced water oxidation reaction（WOR） for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages. WOR is also associated with important reduction reactions, such as oxygen reduction reaction（ORR）, which leads to the production of hydrogen peroxide（H2O2）. These transitions are instrumental in the emergence and evolution of life. In this study, transition metals were loaded onto nitrogen-doped carbon（NDC） prepared under the primitive Earth's atmospheric conditions. These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination. The chemical pathways initiated by the pristine and metal-loaded NDC were investigated. This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet.

关键词： Chemical vapor deposition Nitrogen-doped carbon Oxygen reduction reaction Photocatalysis Water oxidation reaction

Co-host ncRNA MIR503HG/miR-503-5p antagonistically interfere with the crosstalk between fibroblasts and microvascular endothelial cells by affecting the production of LMW FGF2 in pterygium

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 199-208页

作者： Yue-qi Yuan Xing-Yuan yan fang Zheng Ming yan Department of Ophthalmology Zhongnan Hospital of Wuhan UniversityWuhan 430071Hubei ProvinceChina Department of Laboratory Medicine&Center for Gene Diagnosis Zhongnan Hospital of Wuhan UniversityWuhan 430071Hubei ProvinceChina

AIM:To explore the effect of co-host non-coding RNA(ncRNA)MIR503HG/miR-503-5p on the angiogenesis of ***:MIR503HG/miR-503-5p/fibroblast growth factor 2(FGF2)expression levels in pterygium tissues,control conjunctival tissues,and human pterygium fibroblasts(HPF)were examined by reverse transcription-polymerase chain reaction(qRT-PCR)and immunohistochemical *** of MIR503HG/miR-503-5p on low molecular weight FGF2(LWM FGF2),migration and angiogenesis of human retinal microvascular endothelial cells(HRMEC)were determined in an HPF and HRMEC co-culture model using Western blots,wound healing assay,Matrigel-based tube formation assay,and Transwell ***:MIR503HG/miR-503-5p/FGF2 pathway was actively increased in pterygium tissue and there was a negative correlation between the expression of the two ***2 expression level was positively correlated with MIR503HG and negatively correlated with *** MIR503HG/miR-503-5p did not affect the migration and angiogenesis of HRMECs cultured separately,but significantly affected migration and angiogenesis of HRMEC in HPF and HRMEC co-culture *** blotting revealed that MIR503HG/miR-503-5p overexpression significantly increased LMW FGF2 expression in ***:MIR503HG/miR-503-5p inhibits HRMEC migration and angiogenic function by interfering with the interaction between HPF and endothelial cells via reducing LMW FGF2 in HPF.

关键词： pterygium MIR503HG miR-503-5p fibroblast growth factor 2 angiogenesis

The GECAM ground search system for gamma-ray transients

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Science China(Physics,Mechanics & Astronomy) 2025年第3期68卷 161-174页

作者： Ce Cai yan-qiu Zhang Shao-Lin Xiong Ping wang Jian-Hui Li Xiao-Bo Li Cheng-Kui Li Yue Huang Shi-Jie Zheng Li-Ming Song Shuo Xiao qi-Bin Yi Yi Zhao Sheng-Lun Xie Rui qiao yan-qi Du Zhi-Wei guo wang-Chen Xue chao Zheng Jia-Cong Liu Chen-Wei wang Wen-Jun Tan Yue wang Jin-Peng Zhang chao-yang Li guo-Ying Zhao Xiao-Yun Zhao Xiao-Lu Zhang Zhen Zhang Wen-Xi Peng Xiang Ma Jing-yan Shi Dong-Ya guo Jin wang Xin-qiao Li Xiang-yang Wen Zheng-Hua An Fan Zhang College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang050024China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China University of Chinese Academy of Sciences Beijing100049China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang550001China School of Physics and Optoelectronics Xiangtan UniversityXiangtan411105China School of Computer and Information Dezhou UniversityDezhou253023China Institute of Astrophysics Central China Normal UniversityWuhan430079China

In the era of time-domain,multi-messenger astronomy,the detection of transient events on the high-energy electromagnetic sky has become more important than *** gravitational wave high-energy electromagnetic counterpart all-sky monitor(GECAM)is a dedicated mission to monitor gamma-ray transients,launched in December,2020.A real-time on-board trigger and location software,using the traditional signal-to-noise ratio(SNR)method for blind search,is constrained to relatively bright signals due to the limitations in on-board computing resources and the need for real-time *** this work,we developed a ground-based pipeline for GECAM to search for various transients,especially for weak bursts missed by on-board *** pipeline includes both automatic and manual mode,offering options for blind search and targeted *** targeted search is specifically designed to search for interesting weak bursts,such as gravitational wave-associated gamma-ray bursts(GRBs).From the ground search of the data in the first year,GECAM has been triggered by 54 GRBs and other transients,including soft gamma-ray repeaters,X-ray binaries,solar flares,terrestrial gamma-ray *** report the properties of each type of triggers,such as trigger time and light *** this search pipeline and assuming a soft Band spectrum,the GRB detection sensitivity of GECAM is increased to about 1.1×10^(-8)erg cm^(-2)s^(-1)(10-1000 ke V,burst duration of 20 s).These results demonstrate that the GECAM ground search system(both blind search and targeted search)is a versatile pipeline to recover true astrophysical signals which were too weak to be found in the on-board search.

关键词： gamma-ray sources gravitational waves data analysis gamma-ray telescopes

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Anatomic characteristics of the lacrimal sac and adjacent bony structures–a computed tomographicdacryocystography research

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 251-257页

作者： Xin-Han Cui yan-Wen fang Li-Min Zhang Ji-Ni qiu chao-Ran Zhang yan wang Eye Institute and Department of Ophthalmology Eye and ENT Hospital of Fudan UniversityShanghai 200031China NHC Key laboratory of Myopia and Related Eye Diseases Key Laboratory of Myopia and Related Eye DiseasesChinese Academy of Medical SciencesShanghai 200031China Shanghai Key Laboratory of Visual Impairment and Restoration Shanghai 200031China Department of Ophthalmology Children’s Hospital of KaifengKaifeng 475000Henan ProvinceChina

AIM:To describe the anatomic characteristics of the lacrimal sac and its adjacent bone structures and to provide surgical recommendations for endoscopic dacryocystorhinostomy(EN-DCR).METHODS:This retrospective comparative study involved 118 sides with complete nasolacrimal duct obstruction and 83 unaffected sides from 126 *** tomographic-dacryocystography(CT-DCG)scans were performed before lacrimal surgery,and image reconstruction was used to obtain continuous 0.75-mm axial,coronal,and segmental sections for *** morphology of the lacrimal sac and its relationship with adjacent bony structures were determined for measurement,as well as the obstructed ***:The height of the lacrimal sac was 12.99±2.10 mm in this *** operculum of the middle turbinate(OMT)was located vertically in the lower third of the lacrimal ***,the junction between the maxillary bone and the lacrimal bone(MB-LB)was close to,mostly(60.2%)posterior to,the lacrimal *** uncinate process was more frequently attached to the lacrimal bones(75.1%).The obstructions were generally located around the entrance of the nasolacrimal duct(NLD).However,some were placed higher,with 7.63%blocked not lower than the *** was a negative correlation between the diameter of the lacrimal sac and the level of obstruction(r=-0.35,P<0.01).CONCLUSION:In this study,the OMT and MB-LB can be served as the landmarks in *** uncinectomy should be performed in most *** obstructions were generally located around the entrance of the NLD,but some extreme individual variations strongly implies the importance of CT-DCG scanning before surgery.

关键词： lacrimal sac nasolacrimal duct obstruction endoscopic dacryocystorhinostomy computed tomographic-dacryocystography

Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001–2020

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Journal of Geographical Sciences 2025年第1期35卷 39-64页

作者： HE Chenyang wang yanjiao yan Feng LU qi School of Ecological and Environmental Science East China Normal UniversityShanghai200241China Institute of Ecological Conservation and Restoration Chinese Academy of ForestryBeijing100091China National Climate Center China Meteorological AdministrationBeijing100081China

Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ***,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain *** study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–*** indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the *** manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,***,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of *** factors accounted for 70.79%of the variability in *** leaf area index and temperature served as the major driving forces of WUE variation.

关键词： water use efficiency spatiotemporal characteristic influencing factor Tibetan Plateau

Tauroursodeoxycholic acid targets HSP90 to promote protein homeostasis and extends healthy lifespan

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Science China(Life Sciences) 2025年第2期68卷 416-430页

作者： Jia-Yu Liu Yao wang Yue guo Run-qi Zheng Yun-Ying wang yan-yan Shen yan-Hong Liu Ai-Ping Cao Rui-Bo wang Bo-yang Xie Shuai Jiang qiu-Ying Han Jing Chen fang-Ting Dong Kun He Na wang Xin Pan Tao Li Tao Zhou Ai-Ling Li qing Xia Wei-Na Zhang Nanhu Laboratory National Center of Biomedical AnalysisBeijing 100850China

As the elderly population expands,the pursuit of therapeutics to reduce morbidity and extend lifespan has become increasingly *** an FDA-approved drug for chronic cholestatic liver diseases,tauroursodeoxycholic acid(TUDCA),a natural bile acid,offers additional health benefits beyond liver ***,we show that TUDCA extends the lifespan and healthspan of ***,oral supplementation of TUDCA improves fitness in old mice,including clinically relevant phenotypes,exercise capacity and cognitive ***,TUDCA treatment drives broad transcriptional changes correlated with anti-aging ***,we discover that TUDCA targets the chaperone HSP90 to promote its protein refolding *** collaboration further alleviates aging-induced endoplasmic reticulum(ER)stress and facilitates protein homeostasis,thus offering resistance to *** summary,our findings uncover new molecular links between an endogenous metabolite and protein homeostasis,and propose a novel anti-aging strategy that could improve both lifespan and healthspan.

关键词： tauroursodeoxycholic acid lifespan healthspan protein homeostasis