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Modular Synthesis of Multi-substituted Cyclobutanones Enabled by Oxyallyl Cations

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Chinese Journal of Chemistry 2024年第5期42卷 459-463页

作者： Meng wang Zhonggui wang Ping Lu Research Center for Molecular Recognition and Synthesis Department of ChemistryFudan University220 Handan LuShanghai200433 China Present address: Department of Cancer Biology Dana-Farber Cancer Institute Department of Biological Chemistry and Molecular Pharmacology Harvard Medical SchoolBostonMA 02115USA

Stereoselective synthesis of multi-substituted cyclobutanes with different substituents is still a daunting challenge in organic synthesis.We report here a practical and facile approach to synthesizing all-trans 2,3,4-trisubstituted cyclobutanones from readily available dichlorocyclobutanones.The substitution reaction proceeds smoothly via oxyallyl cation intermediates under mild basic conditions.Further transformation to the synthesis of 1,2,3,4-tetrasubstituted cyclobutanes was also explored.

关键词： Diastereoselectivity Modular synthesis Nucleophilic substitution Organohalides Oxyallyl cation Precision functionalization Strained molecules 1,2,3,4-Tetrasubstituted cyclobutanes

Effects of extracellular vesicle-derived noncoding RNAs on pre-metastatic niche and tumor progression

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Genes & Diseases 2024年第1期11卷 176-188页

作者： Zhuang Chen Qiming wang Jinbo Liu Wenkang wang Weitang Yuan Yang Liu Zhenqiang Sun Chengzeng wang Department of Colorectal Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China Academy of Medical Sciences of Zhengzhou University ZhengzhouHenan 450001China Department of Internal Medicine Affiliated Cancer Hospital of Zhengzhou UniversityHenan Cancer HospitalZhengzhouHenan 450008China Department of Breast Surgery The First Affliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China Department of Radiotherapy Affiliated Cancer Hospital of Zhengzhou UniversityHenan Cancer HospitalZhengzhouHenan 450008China The First Affiliated Hospital of Zhengzhou University ZhengzhouHenan 450052China

A pre-metastatic niche(PMN)is a protective microenvironment that facilitates the colonization of disseminating tumor cells in future metastatic organs.Extracellular vesicles(EVs)play a role in intercellular communication by delivering cargoes,such as noncoding RNAs(ncRNAs).The pivotal role of extracellular vesicle-derived noncoding RNAs(EV-ncRNAs)in the PMN has attracted increasing attention.In this review,we summarized the effects of EV-ncRNAs on the PMN in terms of immunosuppression,vascular permeability and angiogenesis,inflammation,metabolic reprogramming,and fibroblast alterations.In particular,we provided a comprehensive overview of the effects of EV-ncRNAs on the PMN in different cancers.Finally,we discussed the promising clinical applications of EV-ncRNAs,including their potential as diagnostic and prognostic markers and therapeutic targets.

关键词： Biomarker Extracellular vesicles Noncoding RNAs

Serum 25-hydroxyvitamin D, genetic susceptibility, and the risk of incident type 2 diabetes: A prospective cohort in East China

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中华医学杂志(英文版) 2024年第8期137卷 972-979页

作者： Sun Ying Zhang Haojie wang Bin wang Yuying Chen Chi Chen Yi Lu Yingli wang Ningjian West China Hospital Sichuan University Chengdu Sichuan 610041 Department of Endocrinology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Shanghai 201203 Institute and Department of Endocrinology and Metabolism Shanghai Ninth People’s Hospital Shanghai JiaoTong University School of Medicine Shanghai 200011 China Department of Endocrinology and Metabolism and Department of Guideline and Rapid Recommendation Cochrane China Center MAGIC China Center Chinese Evidence-Based Medicine Center

Background: The serum vitamin D level varies widely by population, and studies have linked vitamin D levels with the risk of type 2 diabetes mellitus (T2DM). However, the relationship is inconsistent and the impact of vitamin D on T2DM among East Chinese adults is unclear. The study aimed to investigate the association between serum 25-hydroxyvitamin D (25[OH]D) levels and the risk of T2DM and evaluated whether the association is modified by genetic predisposition.Methods: In the Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China) cohort, 1862 participants free of T2DM at baseline were included. A weighted genetic risk score was calculated with 28 variants associated with T2DM. Hierarchical logistic models were used to examine the association of serum 25(OH)D and genetic risk with T2DM.Results: After a 5-year follow-up, 132 cases of T2DM were documented. We observed no significant association between quartiles of serum 25(OH)D and T2DM risk after multivariable adjustment (χ2 = 0.571,Pfor trend = 0.426). Compared to those in the lowest quartile of 25(OH)D, the odds ratios (ORs) (95% confidence interval [CI]) for participants with increased quartiles were 1.29 (0.74-2.25), 1.35 (0.77-2.36), and 1.27 (0.72-2.24), respectively. We observed a positive association of glycated hemoglobin (HbA1c) with 25(OH)D at baseline (β = 1.752,P = 0.001) and after follow-up (β = 1.385,P = 0.003), and a negative association of ln conversion homeostasis model assessment (HOMA)-β with 25(OH)D at baseline (β = -0.982,P = 0.021). There was no significant interaction between 25(OH)D and diabetes genetic predisposition on the risk of T2DM (χ2 = 2.710,Pfor interaction = 0.100). The lowest OR (95% CI) of T2DM was among participants with low genetic risk and the highest quartile of 25(OH)D (0.17 [0.05–0.62]).Conclusion: Serum 25(OH)D may be irrelevant to the risk of incident T2DM among East Chinese adults regardless of genetic predisposition.

关键词： Vitamin D Diabetes mellitus, Type 2 Genetic predisposition to disease Prospective cohort Glycated hemoglobin SPECT-China

Musculoskeletal ultrasound to evaluate the efficacy of acupuncture: a review

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Journal of Traditional Chinese Medicine 2024年第3期44卷 629-632页

作者： wang Dingyue YU Yana wang Yiyuan ZHANG Zhen Department of Ultrasound the First Affiliated Hospital of China Medical University

Acupuncture is a typical example of Traditional Chinese Medicine and has been used in China for hundreds of years to treat a wide range of illnesses. However, in the clinic, issues and deficiencies were primarily seen in four areas: loss of accuracy in the operation process; difficulty understanding the depth of acupuncture; difficulty using reinforcing and reducing techniques; and lack of a clear dynamic effect of acupuncture points following acupuncture. Musculoskeletal ultrasonography may quantitatively evaluate the acupuncture location and display the distribution of small nerves near and within the fascia of the acupuncture point in real time. The subjects were asked how they felt about receiving Qi when the needle body reached different depths and different tissues. The Qi obtained from an acupuncture point and the connective tissue of the fascia can be further understood by combining the physiological response of the acupuncture point with the anatomical structure,which offers a new method for defining the nature of the acupuncture point and standardizing the acupuncture point.

关键词： acupuncture De Qi dynamic effect musculoskeletal ultrasound visualization

Characterization of a smog chamber for studying formation of gas-phase products and secondary organic aerosol

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Journal of Environmental Sciences 2024年第2期136卷 570-582页

作者： Qi Yuan Zhuozhi Zhang Meng wang Kin Fai Ho Tao wang Shuncheng Lee Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina School of Public Health and Primary Care The Chinese University of Hong KongShatinHong KongChina

Smog chambers provide a potent approach to explore the secondary organic aerosol formation under varied conditions.This study describes the construction and characterization of a new smog chamber facility for studying the formation mechanisms of gas-phase products and secondary organic aerosol from the photooxidation of volatile organic compounds.The chamber is a 5.4 m^(3) Fluorinated Ethylene Propylene(FEP)Teflon reactor with the potential to perform photooxidation experiments at controlled temperature and relative humidity.Detailed characterizations were conducted for evaluation of stability of environmental parameters,mixing time,background contamination,light intensity,and wall losses of gases and particles.The photolysis rate of NO_(2)(J_(NO2))ranged from(1.02-3.32)×10^(-3)sec^(-1),comparable to the average J_(NO2)in ambient environment.The wall loss rates for NO,NO_(2),and O_(3)were 0.47×10^(-4),0.37×10^(-4),and 1.17×10^(-4)min^(-1),while wall loss of toluene was obsoletely found in a 6 hr test.The particle number wall loss rates are(0.01-2.46)×10^(-3)min^(-1)for 40-350 nm with an average lifetime of more than one day.A series of toluene photooxidation experiments were carried out in absence of NO_xunder dry conditions.The results of the simulation experiments demonstrated that the chamber is well designed to simulate photolysis progress in the atmosphere.

关键词： Smog chamber Gas-phase oxidation Chamber characterization Chemical mechanism

Recent advances in solving Li_(2)CO_(3) problems in garnet-based solid-state battery: A systematic review(2020-2023)

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Journal of Energy Chemistry 2024年第3期90卷 58-76,I0004页

作者： Shaoxiong Han Ziqi wang Yue Ma Yanlan Zhang Yongzhen wang Xiaomin wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Shanxi Joint Laboratory of Coal based Solid Waste Resource Utilization and Green Ecological Development Taiyuan 030024ShanxiChina

Garnet solid electrolytes are one of the most promising electrolytes for solid-state batteries.However,Li_(2)CO_(3) is a critical issue that hinders the practical application of garnet-based solid-state lithium-ion batteries.There are two sources of Li_(2)CO_(3) contamination.The main one is the aging of garnet electrolytes in the *** electrolytes can react with H_(2)O and CO_(2) in the air to form Li_(2)CO_(3),which reduces ion conductivity,increases electrode/garnet electrolyte interface resistance,and deteriorates the electrochemical performance of the battery.Various strategies,such as elemental doping,grain boundary manipulation,and interface engineering,have been suggested to address these issues.The other is the passivation layer(Li_(2)CO_(3),Li_3N,LiOH,Li_(2)O) formed on the surface of the lithium foil after long-term storage,which is ignored by most researchers.To better understand the current strategies and future trends to address the Li_(2)CO_(3) problem,this perspective provides a systematic review of journals published in this field from 2020-2023.

关键词： Solid-state batteries Garnet electrolytes Air stability Interface engineering Lithium foil contamination

Molecular design of recyclable thermosetting polyimide and its composite with excellent mechanical and tribological properties

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Friction 2024年第3期12卷 452-461页

作者： Xiaoyue wang Zenghui YANG Tingmei wang Qihua wang Xinrui ZHANG Song LI Key Laboratory of Science and Technology on Wear and Protection of Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Recyclability of thermosetting polymers and their composites is a challenge for alleviating environmental pollution and resource waste.In this study,solvent-recyclable thermosetting polyimide(PI)and its composite were successfully synthesized.The tensile strength,elongation at break,and Young’s modulus of PI are 108.70±7.29 MPa,19.35%±3.89%,and 2336.42±128.00 MPa,respectively.The addition of reduced graphene oxide(RGO)not only enhances the mechanical properties of PI but also endows it with excellent tribological properties.The PI illustrates a high recycling efficiency of 94.15%,but the recycled composite exhibits inferior mechanical properties.The recycling and utilization of PI and its composite are realized through imine bonds(-C=N),which provides new guidance for solving the problem of environmental pollution and resource waste and is potential application in the field of sustainable tribology.

关键词： thermosetting polyimide(PI) recyclability dynamic covalent bonds friction and wear polymer composites

A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea

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China Ocean Engineering 2024年第1期38卷 104-116页

作者： wang Ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation technique.The wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been proposed.The likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will occur.It is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation method.This study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency.

关键词： wave crest amplitude freak waves short crested sea transformed linear simulation

How geographic accessibility and rural governance mitigate the impact of multiple risks on rural households' well-being: Evidence from the Dabie Mountains in China

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Journal of Geographical Sciences 2024年第6期34卷 1195-1227页

作者： wang Feifan wang Ying Department of Land Resources Management School of Public AdministrationChina University of GeosciencesWuhan 430074China Key Laboratory of the MinistryofNatural Resources for Legal Research Wuhan 430074China

Despite previous studies on the interconnectedness of livelihood risks and human well-being, limited emphasis has been placed on the influence of geographic accessibility and rural governance on the well-being of rural households. Furthermore, the interplay between geographic accessibility, rural governance, and livelihood risk remains inadequately explored. Based on 522 household samples collected in the Dabie Mounand ordinary least squares regression, this study examines the influence of multiple risks on the subjective well-being of rural households by investigating the moderating roles played by geographic accessibility and rural governance. The results show that(1) multiple risk factors have a significant negative effect on rural households' well-being(β=-0.219, p<0.01);(2) geographic accessibility has a weak positive effect on rural households' well-being(β=0.064, p<0.1) compared to rural governance, which plays a larger positive role(β=0.228, p<0.01);and(3) geographic accessibility has a significant moderating effect on the relationship between multiple risks and rural households' well-being, decreasing the adverse impact of multiple risks on households' well-being. Our findings suggest that geographic accessibility and rural governance have positive implications for enhancing the well-being of rural households. The findings provide policy insight into mitigating livelihood risks and their negative impacts on household well-being in mountainous regions worldwide.

关键词： multiple risks rural governance livelihood well-being index spatial traps Dabie Mountains China