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Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo qiu-Quan Pan Qi-wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

MET receptor tyrosine kinase promotes the generation of functional synapses in adult cortical circuits

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Neural Regeneration Research 2025年第5期20卷 1431-1444页

作者： Yuehua Cui Xiaokuang Ma Jing wei Chang Chen Neha Shakir Hitesch Guirram Zhiyu Dai Trent Anderson Deveroux Ferguson Shenfeng qiu Basic Medical Sciences University of Arizona College of Medicine-PhoenixPhoenixAZUSA Department of Medicine University of Arizona College of Medicine-PhoenixPhoenixAZUSA

Loss of synapse and functional connectivity in brain circuits is associated with aging and neurodegeneration,however,few molecular mechanisms are known to intrinsically promote synaptogenesis or enhance synapse *** have previously shown that MET receptor tyrosine kinase in the developing cortical circuits promotes dendritic growth and dendritic spine *** investigate whether enhancing MET in adult cortex has synapse regenerating potential,we created a knockin mouse line,in which the human MET gene expression and signaling can be turned on in adult(10–12 months)cortical neurons through doxycycline-containing *** found that similar to the developing brain,turning on MET signaling in the adult cortex activates small GTPases and increases spine density in prefrontal projection *** findings are further corroborated by increased synaptic activity and transient generation of immature silent *** MET signaling resulted in an increasedα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/N-methyl-Daspartate(AMPA/NMDA)receptor current ratio,indicative of enhanced synaptic function and *** data reveal that enhancing MET signaling could be an interventional approach to promote synaptogenesis and preserve functional connectivity in the adult *** findings may have implications for regenerative therapy in aging and neurodegeneration conditions.

关键词： aging circuit connectivity cortical circuits molecular mechanisms neural regeneration neurodegeneration synapses

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三维浮体二阶辐射问题的实时模拟

水动力学研究与进展（A辑） 2003年第4期18卷 489-498页

作者：柏威滕斌邱大洪大连理工大学海岸和近海工程国家重点实验室辽宁大连116024

采用二阶时域理论对任意三维物体的非线性波浪问题进行了研究。对自由表面边界条件和物面边界条件进行了Taylor级数展开 ,Stokes摄动展开用于建立相应的一阶和二阶边值问题 ,而且此边值问题的计算域不随时间变化。使用基于B -样条的边... 详细信息

采用二阶时域理论对任意三维物体的非线性波浪问题进行了研究。对自由表面边界条件和物面边界条件进行了Taylor级数展开 ,Stokes摄动展开用于建立相应的一阶和二阶边值问题 ,而且此边值问题的计算域不随时间变化。使用基于B -样条的边界元方法计算每一时刻的二阶波浪场 ,二阶自由表面边界条件在时间上进行数值积分。在自由表面加一个人工阻尼层以避免波浪的反射。对二阶物面边界条件采用数学手段 ,推导出一个没有二阶空间导数的表达式 ,以便于计算。本文对强迫正弦垂荡和纵荡运动的截断圆柱进行了计算 ,讨论了漂浮结构的二阶水动压力影响。

关键词：三维浮体二阶辐射问题实时模拟二阶时域理论非线性波浪问题边界元方法水动压力漂浮结构海洋工程

Surface-confined persistent luminescence with amplified FRET efficiency for cell-cell communication monitoring

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Science China Chemistry 2025年

作者： Ziyun Miao Wenjing Dai Yubin Jin bing Qi Jiayi Chen Lingling qiu Yurong wei Jie Wang The Key Lab of Health Chemistry&Molecular Diagnosis of Suzhou College of ChemistryChemical Engineering&Materials ScienceSoochow University

Microbial communication monitoring is vital for understanding the mechanisms beneath gut microbiota equilibrium, infections,and biomanufacturing. Herein, we reported monitoring bacterial communication by surface-confined persistent ***, we constructed core-shell structured Zn1.4Ga1.2Ge0.4O4@Zn1.4Ga1.2Ge0.4O4:Cr（ZGGO@ZGGO:Cr） persistent luminescence nanoparticles（PLNPs） with amplified FRET efficiency for the detection of azoreductase（AzoR） that participates in bacterial communication. ZGGO@ZGGO:Cr nanoparticles were functionalized with an azo black hole quencher（ZGGO@ZGGO:Cr-BHQ-3）. Due to the proximity of surface-confined persistent luminescence with the surface-bound BHQ-3,ZGGO@ZGGO:Cr-BHQ-3 exhibited a FRET efficiency up to 1.6 times that of traditional ZGGO:Cr-BHQ-3. Further, the specific catalytic reduction of azo bonds in BHQ-3 by bacterial extracellular AzoR recovers the persistent luminescence of ZGGO@ZGGO:Cr. ZGGO@ZGGO:Cr-BHQ-3 displayed superior sensitivity and speed in detecting extracellular AzoR over ZGGO:Cr-BHQ-3, attributed to its surface-confined persistent luminescence. We found that the peak secretion of AzoR occurs during the exponential growth period of bacteria including S. aureus and E. coli based on the persistent luminescence recovery rate of ZGGO@ZGGO:Cr-BHQ-3. Furthermore, ZGGO@ZGGO:Cr-BHQ-3 was used to probe the communication between different bacterial species. R. palustris is a kind of lycopene-production bacteria. We found that the cohabitation of R. palustris and S. putrefaciens boosted both AzoR secretion and lycopene production. Moreover, the secretion and activity of AzoR positively correlated with lycopene production, suggesting that AzoR may participate in the communication between R. palustris and S. putrefaciens to promote lycopene production. This study offers a robust method to enhance PLNP-based biosensing sensitivity and provides a promising strategy for microbial communication monitoring.

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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders

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Neural Regeneration Research 2025年第5期20卷 1258-1276页

作者： Qing qiu Mengting Yang Danfeng Gong Haiying Liang Tingting Chen Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Jiangsu Province Key Laboratory of Inflammation and Molecular Drug Target NantongJiangsu ProvinceChina Department of Pharmacy Longyan First Affiliated Hospital of Fujian Medical UniversityLongyanFujian ProvinceChina

The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be u

关键词： astrocytes calcium channels central nervous system extracellular ion concentration microglia neurological disorders neurons potassium channels

Electrocatalytic cleavage of a lignin β-O-4 model compound and coupling with nitrogen-containing aromatics using Prussian blue analogue-derived nickel–cobalt spinel

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Journal of Energy Chemistry 2025年第1期100卷 628-636页

作者： Yi Qi Xueying Chen Bowen Liu Xuliang Lin Xueqing qiu Yanlin Qin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light Industry Guangdong University of Technology Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Guangdong Basic Research Center of Excellence for Ecological Security and Green Development Guangdong University of Technology

Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great *** demonstrate the targeted synthesis and cation modulation of NiCo2O4spinel nanoboxes,synthesized via cation exchange and calcination *** catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and *** catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as *** porous architecture and polymetallic composition of the NiCo2O4spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for *** innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT *** work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.

关键词： Spinel Biomass valorization Electrocatalysis Lignin oxidation Coupling

Constructing Pr-doped CoOOH catalytic sites for efficient electrooxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 234-244页

作者： Botao Fan Hao Zhang Bang Gu Feng qiu qiue Cao Wenhao Fang School of Chemical Science and Technology Yunnan University National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University

Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current ***,a Pr-doped Co（OH）2hexagonal sheet （Pr/Co=1/9,in mole） is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural （HMF） oxidation reaction（HMFOR） to produce 2,5-furandicarboxylic acid （FDCA）.This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V （***） and requires only 1.10 V （***） to reach a current density of 10 mA cm-2for HMFOR,significantly outperforming Co（OH）2benchmark (i.e.,210 mV higher to reach10 m A cm-2).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical *** unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward *** can be one of the most outstanding results for Co-based HMFOR catalysts to date in the *** this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.

关键词： Bioconversion

Solar trough receiver with V-grooved light traps for efficiency improvement

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Science China Technological Sciences 2025年第1期 146-156页

作者： bin LIU Qing LI Yu qiu School of Energy Science and Engineering Central South University

Parabolic trough collector is a promising technology for both domestic and industrial heat supplies. To enhance the collector efficiency, a modified trough receiver with dozens of V-grooved light traps incorporated into its lower-half absorber was introduced. For assessing the performance of this receiver, a solar-thermal-stress coupled model was established. Using this model, firstly, the effects of the V-grooved light traps were investigated. The results reveal that, compared to the conventional trough receiver, the modified trough receivers equipped with different traps can reduce their optical losses by 81.9–138.0 Wm-1（i.e., 15.0%–25.2%）, improving their optical efficiencies by 1.60%–2.69%. However, these traps also result in increased thermal loss from the receiver. Therefore, there is no single optimal modified trough receiver that consistently outperforms all other receivers across all possible conditions. Nonetheless, the MTR30-3 and MTR60-3 receivers emerge as the optimized choices due to their better solar-thermal performance. Subsequently, performance evaluation reveals that the two optimized receivers can enhance the receiver efficiencies within the typical solar irradiance range by 0.02%–2.65% and 0.05%–1.70% when the inlet fluid temperatures are below 488 and 523 K, respectively. Consequently, the collector efficiencies can be improved by 0.02%–2.49% and 0.05%–1.60%, respectively. Additionally, thermal stress analysis verifies that the two optimized receivers remain within safe limits under all typical conditions. Given that the heating temperature of a typical solar collector for domestic or industrial heat supply is typically below 523 K, the integration of the two optimized receivers has the capability to effectively enhance the overall collector efficiency.

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Number rigid determinantal point processes induced by generalized Cantor sets

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Acta Mathematica Sinica,English Series 2025年

作者： Zhaofeng LIN Yanqi qiu Kai WANG School of Fundamental Physics and Mathematical Sciences HIAS University of Chinese Academy of Sciences School of Mathematical Sciences Fudan University

We consider the Ghosh-Peres number rigidity of translation-invariant determinantal point processes on the real line R, whose correlation kernels are induced by the Fourier transform of the indicators of generalized Cantor sets in the unit interval. Our main results show that for any givenθ∈(0, 1), there exists a generalized Cantor set with Lebesgue measure θ, such that the corresponding determinantal point process is Ghosh-Peres number rigid.

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