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氟烷基化FeOOH/PVDF共混膜微结构调控及其膜蒸馏性能研究
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作者 高海富 贺龙飞 +4 位作者 孙佳静 武春瑞 陈华艳 王暄 吕晓龙 《高分子学报》 北大核心 2026年第1期143-156,共14页
膜蒸馏(MD)技术是海水淡化与高浓水体资源化的重要手段,优异的疏水性和均匀的孔结构是解决膜污染、润湿问题和保障MD高效运行的关键.本工作设计了溶解同步功能化、羟基诱导相分离方法:基于水解缩合反应在铸膜液溶解过程中将全氟辛基三... 膜蒸馏(MD)技术是海水淡化与高浓水体资源化的重要手段,优异的疏水性和均匀的孔结构是解决膜污染、润湿问题和保障MD高效运行的关键.本工作设计了溶解同步功能化、羟基诱导相分离方法:基于水解缩合反应在铸膜液溶解过程中将全氟辛基三乙氧基硅烷(FAS)接枝于羟基氧化铁(FeOOH)纳米棒表面,形成氟硅烷化羟基氧化铁(F-FeOOH),增强疏水性的同时解决纳米粒子团聚问题,进而在相分离成膜过程中通过F-FeOOH调控聚偏氟乙烯(PVDF)膜的晶型结构,规范聚合物链胶束生长与固化,优化膜表面及孔结构.研究表明,F-FeOOH的引入,在增强材料化学疏水性的同时诱导PVDF分子链晶型向γ晶型转变,改性膜疏水性显著提升,膜下表面的纯水接触角可达135.5°,相比于原膜提升了42.6%;膜孔径均匀性提升,最可几孔径占比达98.4%;MD通量达到38.5 kg/(m^(2)·h),与原膜相比提升了75.0%;膜截留率超过99.9%,且在30 h的防污染和抗润湿实验中表现出良好的稳定性. 展开更多
关键词 氟硅烷化羟基氧化铁 聚偏氟乙烯 疏水微孔膜 膜蒸馏 膜润湿
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Stem cell repair strategies for epilepsy
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作者 Xiao Ma Zitong wang +7 位作者 Yinuo Niu Jie Zhao Xiaorui wang xuan wang Fang Yang Dong Wei Zhongqing Sun Wen Jiang 《Neural Regeneration Research》 2026年第4期1428-1446,共19页
Epilepsy is a serious neurological disorder;however,the effectiveness of current medications is often suboptimal.Recently,stem cell technology has demonstrated remarkable therapeutic potential in addressing various ne... Epilepsy is a serious neurological disorder;however,the effectiveness of current medications is often suboptimal.Recently,stem cell technology has demonstrated remarkable therapeutic potential in addressing various neurological diseases,igniting interest in its applicability for epilepsy treatment.This comprehensive review summarizes different therapeutic approaches utilizing various types of stem cells.Preclinical experiments have explored the use and potential therapeutic effects of mesenchymal stem cells,including genetically modified variants.Clinical trials involving patientderived mesenchymal stem cells have shown promising results,with reductions in the frequency of epileptic seizures and improvements in neurological,cognitive,and motor functions reported.Another promising therapeutic strategy involves neural stem cells.These cells can be cultured outside the body and directed to differentiate into specific cell types.The transplant of neural stem cells has the potential to replace lost inhibitory interneurons,providing a novel treatment avenue for epilepsy.Embryonic stem cells are characterized by their significant capacity for self-renewal and their ability to differentiate into any type of somatic cell.In epilepsy treatment,embryonic stem cells can serve three primary functions:neuron regeneration,the maintenance of cellular homeostasis,and restorative activity.One notable strategy involves differentiating embryonic stem cells intoγ-aminobutyric acidergic neurons for transplantation into lesion sites.This approach is currently undergoing clinical trials and could be a breakthrough in the treatment of refractory epilepsy.Induced pluripotent stem cells share the same genetic background as the donor,thereby reducing the risk of immune rejection and addressing ethical concerns.However,research on induced pluripotent stem cell therapy remains in the preclinical stage.Despite the promise of stem cell therapies for epilepsy,several limitations must be addressed.Safety concerns persist,including issues such as tumor formation,and the low survival rate of transplanted cells remains a significant challenge.Additionally,the high cost of these treatments may be prohibitive for some patients.In summary,stem cell therapy shows considerable promise in managing epilepsy,but further research is needed to overcome its existing limitations and enhance its clinical applicability. 展开更多
关键词 astrocyte transdifferentiation cell therapy cell transplantation clinical trials embryonic pluripotent stem cells EPILEPSY gamma-aminobutyric acidergic neuron induced pluripotent stem cells mesenchymal stem cells nerve regeneration neural stem cells organoid
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Dual‑salt electrolyte design enabled by synergistic solvation and interfacial regulation for fast charging of lithium‑ion batteries
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作者 Jun-Sen Jiang Lan-Fang Que +5 位作者 Rui-Chi Li Fu-Da Yu xuan wang Ji-Huai Wu Can-Zhong Lu Yi-Ming Xie 《Journal of Energy Chemistry》 2026年第1期484-494,I0011,共12页
To address the performance limitations of conventional LiPF6-carbonate electrolytes under extreme temperatures and high-rate charging,lithium difluoro(oxalato)borate(LiDFOB)is introduced into the LiPF6-carbonate elect... To address the performance limitations of conventional LiPF6-carbonate electrolytes under extreme temperatures and high-rate charging,lithium difluoro(oxalato)borate(LiDFOB)is introduced into the LiPF6-carbonate electrolyte to form a dual-salt system.The optimization mechanism enhancing the fast-charging capability of LiNi_(0.52)Co_(0.2)Mn_(0.28)O_(2)(NCM523)cathode is systematically explored.Molecular dynamics simulations and electrochemical characterization demonstrate the reconstruction of Li+solvation structures,expanding the voltage window and reducting Li^(+)desolvation barriers.In addition,the incorporation of LiDFOB induces the generation of a LiF/Li_(x)BO_(y)F_(z)-enriched cathode-electrolyte interphase,which effectively suppresses the dissolution of transition metals.In situ impedance measurements reveal the accelerated interfacial charge transfer kinetics.As expected,the NCM523 cathode achieves an 82%state-of-charge(SOC)in 12 min at 5 C(25°C)with 87%capacity retention after 100 cycles,and exhibits a 65%higher discharge capacity at 1 C than the baseline at−20°C.The 1 Ah pouch cells based on LiNi_(0.52)Co_(0.2)Mn_(0.28)O_(2)cathodes,graphite anodes,and 0.5 wt%LiDFOB-modified electrolyte demonstrate fast-charging capabilities:charging 97%of the pouch cell capacity within 30 min(2 C)and 80%within 15 min(4 C)at 25°C.This study offers a practical electrolyte design strategy that enhances the fast-charging performance of lithium-ion batteries(LIBs)over a wide temperature range(from−20 to 25°C). 展开更多
关键词 Lithium-ion batteries Fast charging Li^(+)solvation structure LiF/Li_(x)BO_(y)F_(z)enriched interface Dual-salt LiPF6-carbonate electrolyte
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Green and High-Yield Recovery of Phosphorus from Municipal Wastewater for LiFePO_(4)Batteries 被引量:1
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作者 Yijiao Chang xuan wang +6 位作者 Bolin Zhao Anjie Li Yiru Wu Bohua Wen Bing Li Xiao-Yan Li Lin Lin 《Engineering》 2025年第2期234-242,共9页
The rapidly growing demand for lithium iron phosphate(LiFePO_(4))as the cathode material of lithium-ion batteries(LIBs)has aggravated the scarcity of phosphorus(P)reserves on Earth.This study introduces an environment... The rapidly growing demand for lithium iron phosphate(LiFePO_(4))as the cathode material of lithium-ion batteries(LIBs)has aggravated the scarcity of phosphorus(P)reserves on Earth.This study introduces an environmentally friendly and economical method of P recovery from municipal wastewater,providing the P source for LiFePO_(4) cathodes.The novel approach utilizes the sludge of Fe-coagulant-based chemical P removal(CPR)in wastewater treatment.After a sintering treatment with acid washing,the CPR sludge,enriched with P and Fe,transforms into purified P-Fe oxides(Fe2.1P1.0O5.6).These oxides can substitute up to 35%of the FePO_(4) reagent as precursor,producing a carbon-coated LiFePO_(4)(LiFePO_(4)/C)cathode with a specific discharge capacity of 114.9 mA·h·g^(-1)at current density of 17 mA·g^(-1)),and cycle stability of 99.2%after 100 cycles.The enhanced cycle performance of the as-prepared LiFePO_(4)/C cathode may be attributed to the incorporations of impurities(such as Ca^(2+)and Na^(+))from sludge,with improved stability of crystal structure.Unlike conventional P-fertilizers,this P recovery technology converts 100%of P in CPR sludge into the production of value-added LiFePO_(4)/C cathodes.The recovered P from municipal wastewater can meet up to 35%of the P demand in the Chinese LIBs industry,offering a cost-effective solution for addressing the pressing challenges of P scarcity. 展开更多
关键词 Municipal wastewater Chemical phosphorus removal sludge Lithium iron phosphate Lithium-ion batteries Phosphorus recovery
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Natural compound rosmarinic acid displays anti-tumor activity in colorectal cancer cells by suppressing nuclear factor-kappa B signaling 被引量:1
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作者 Wen-Yue Liu Han wang +5 位作者 Xin Xu xuan wang Kun-Kun Han Wen-Dao You Yili Yang Tao Zhang 《World Journal of Clinical Oncology》 2025年第5期171-180,共10页
BACKGROUND Rosmarinic acid(RA)is a natural polyphenol carboxylic acid known for its role in chemoprevention.Given its widespread use as a food additive,we are interested in whether RA affects the development of colore... BACKGROUND Rosmarinic acid(RA)is a natural polyphenol carboxylic acid known for its role in chemoprevention.Given its widespread use as a food additive,we are interested in whether RA affects the development of colorectal cancer(CRC).AIM To examine the anti-tumor effects of RA on various CRC cell lines,and to further investigate the possible mechanisms.METHODS Cell Counting Kit-8 assay and optical microscopy imaging were used to evaluate the viability of CRC cell lines.Western blot,quantitative real-time polymerase chain reaction,and flow cytometry analyses were performed to assess cell viability and activation of nuclear factor-kappa B(NF-κB)signaling.Molecular modeling was used to assess the interaction between RA and inhibitory kappa B kinase beta.Luciferase assay was used to examine the activity of NF-κB-driven transcription.The combinations of RA with 5-fluorouracil or oxaliplatin were utilized to evaluate the potential synergistic action of RA with the chemotherapeutics.RESULTS RA exerted potent cytotoxic actions on all six CRC cell lines examined.RA was docked nicely into the binding pocket of inhibitory kappa B kinase beta by molecular modeling.The activity of NF-κB-driven luciferase and the phosphorylation of NF-κB p65 were decreased after exposure to the compound.Lipopolysaccharide-induced NF-κB activation was effectively inhibited by RA,too.Further,RA downregulated the expression of cell proliferationrelated cyclin D1 and MYC,which are target genes of NF-κB.Of note,the cytotoxic actions of 5-fluorouracil and oxaliplatin were markedly enhanced by RA in those CRC cells.CONCLUSION Our results indicate that RA inhibits NF-κB signaling and induces apoptosis in CRC cells.It enhances the cytotoxic actions of chemotherapeutics and might help to improve the chemotherapy of CRC. 展开更多
关键词 Rosmarinic acid Colorectal cancer Cell death Nuclear factor-kappa B signaling CHEMOTHERAPY
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Ultrastrong nonflammable in-situ polymer electrolyte with enhanced interface stability boosting high-voltage Li metal batteries under harsh conditions 被引量:1
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作者 Lisi Xu xuan wang +3 位作者 Yilu Wu Chaoyang Li Kuirong Deng Zhenhua Yan 《Journal of Energy Chemistry》 2025年第3期63-72,共10页
In-situ polymer electrolytes prepared by Li salt-initiated polymerization are promising electrolytes for solid-state Li metal batteries owing to their enhanced interface contact and facile and green preparation proces... In-situ polymer electrolytes prepared by Li salt-initiated polymerization are promising electrolytes for solid-state Li metal batteries owing to their enhanced interface contact and facile and green preparation process.However,conventional in-situ polymer electrolytes suffer from poor interface stability,low mechanical strength,low oxidation stability,and certain flammability.Herein,a silsesquioxane(POSS)-nanocage-crosslinked in-situ polymer electrolyte(POSS-DOL@PI-F)regulated by fluorinated plasticizer and enhanced by polyimide skeleton is fabricated by Li salt initiated in-situ polymerization.Polyimide skeleton and POSS-nanocage-crosslinked network significantly enhance the tensile strength(22.8 MPa)and thermal stability(200℃)of POSS-DOL@PI-F.Fluorinated plasticizer improves ionic conductivity(6.83×10^(-4)S cm^(-1)),flame retardance,and oxidation stability(5.0 V)of POSS-DOL@PI-F.The fluorinated plasticizer of POSS-DOL@PI-F constructs robust LiF-rich solid electrolyte interphases and cathode electrolyte interphases,thereby dramatically enhancing the interface stability of Li metal anodes and LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NCM811)cathodes.POSS-DOL@PI-F enables stable,long-term(1200 h),and dendrite-free cycle of Li‖Li cells.POSS-DOL@PI-F significantly boosts the performance of Li‖NCM811cells,which display superior cycle stability under harsh conditions of high voltage(4.5 V),high temperature(60℃),low temperature(-20℃),and high areal capacity.This work provides a rational design strategy for safe and efficient polymer electrolytes. 展开更多
关键词 Polymer electrolytes Interface stability Li salt-initiated polymerization Flame retardant Mechanical strength
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Model-free prediction of chaotic dynamics with parameter-aware reservoir computing 被引量:1
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作者 Jianmin Guo Yao Du +3 位作者 Haibo Luo xuan wang Yizhen Yu Xingang wang 《Chinese Physics B》 2025年第4期143-152,共10页
Model-free,data-driven prediction of chaotic motions is a long-standing challenge in nonlinear science.Stimulated by the recent progress in machine learning,considerable attention has been given to the inference of ch... Model-free,data-driven prediction of chaotic motions is a long-standing challenge in nonlinear science.Stimulated by the recent progress in machine learning,considerable attention has been given to the inference of chaos by the technique of reservoir computing(RC).In particular,by incorporating a parameter-control channel into the standard RC,it is demonstrated that the machine is able to not only replicate the dynamics of the training states,but also infer new dynamics not included in the training set.The new machine-learning scheme,termed parameter-aware RC,opens up new avenues for data-based analysis of chaotic systems,and holds promise for predicting and controlling many real-world complex systems.Here,using typical chaotic systems as examples,we give a comprehensive introduction to this powerful machine-learning technique,including the algorithm,the implementation,the performance,and the open questions calling for further studies. 展开更多
关键词 chaos prediction time-series analysis bifurcation diagram parameter-aware reservoir computing
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Role of Ferroptosis in Cerebral Ischemia- Reperfusion Injury 被引量:1
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作者 Jianmeng Lv Tao wang +3 位作者 Yajuan Pan Juan Liu Zheng Han xuan wang 《Journal of Clinical and Nursing Research》 2025年第5期8-18,共11页
Ferroptosis is a novel form of non-apoptotic cell death that has been widely studied in recent years and is involved in a variety of pathophysiological processes.The core treatment goal of ischemic stroke is to restor... Ferroptosis is a novel form of non-apoptotic cell death that has been widely studied in recent years and is involved in a variety of pathophysiological processes.The core treatment goal of ischemic stroke is to restore blood flow as early as possible,while the pathological mechanism of reperfusion injury after restoring blood flow is complex,involving oxidative stress,calcium overload,and inflammatory response.In recent years,more and more studies have found that ferroptosis mediation is involved in the occurrence and development of cerebral ischemia-reperfusion injury.This paper elaborates on the concept,mechanisms,and regulation of ferroptosis,detailing its role in cerebral ischemia-reperfusion injury and potential inhibition strategies.The aim is to deepen the understanding of ferroptosis in this pathological process and provide insights for possible targeted therapies. 展开更多
关键词 Ferroptosis Ischemic stroke Reperfusion injury Targeted therapy
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Wafer‑Scale Vertical 1D GaN Nanorods/2D MoS_(2)/PEDOT:PSS for Piezophototronic Effect‑Enhanced Self‑Powered Flexible Photodetectors
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作者 Xin Tang Hongsheng Jiang +3 位作者 Zhengliang Lin xuan wang Wenliang wang Guoqiang Li 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期102-116,共15页
van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible photodetection.Currently,hand-stacked vdW-type phot... van der Waals(vdW)heterostructures constructed by lowdimensional(0D,1D,and 2D)materials are emerging as one of the most appealing systems in next-generation flexible photodetection.Currently,hand-stacked vdW-type photodetectors are not compatible with large-areaarray fabrication and show unimpressive performance in self-powered mode.Herein,vertical 1D GaN nanorods arrays(NRAs)/2D MoS_(2)/PEDOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly.The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W^(−1)and a high detectivity of 1.2×10^(11)Jones,as well as a fast response speed of 54/71μs,thanks to the strong light absorption of GaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction.Notably,the strain-tunable photodetection performances of device have been demonstrated.Impressively,the device at−0.78%strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W^(−1),a detectivity of 2.6×10^(11)Jones,and response times of 40/45μs,which are superior to the state-of-the-art self-powered flexible photodetectors.This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection,which performs well in flexible sensors. 展开更多
关键词 Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors
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共价有机框架的设计及其在催化C—H活化领域的应用进展
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作者 王轩 柳茂陈 +1 位作者 钟瑶 宋仁杰 《有机化学》 北大核心 2025年第2期448-465,共18页
共价有机框架(COFs)作为新兴多孔材料,因其独特的可设计性、较高的孔隙度和结晶度以及可修饰的孔道环境,有望成为催化领域中一种重要的催化剂.近年来,随着对COFs材料研究的逐渐深入,人们对其结构设计更为多样化,逐渐探索出多种有关COFs... 共价有机框架(COFs)作为新兴多孔材料,因其独特的可设计性、较高的孔隙度和结晶度以及可修饰的孔道环境,有望成为催化领域中一种重要的催化剂.近年来,随着对COFs材料研究的逐渐深入,人们对其结构设计更为多样化,逐渐探索出多种有关COFs材料的构建策略,使其在催化领域中展现出非凡的应用前景.因此,从COFs材料的基本结构出发,全面地讨论了常见的构建策略,并列举部分COFs材料在C—H活化领域的实际应用,详细介绍其在这些反应中的催化机理.最后,讨论了COFs材料当前在催化领域面临的问题与困境,期望为COFs材料在催化C—H活化领域未来的发展提供有益指导. 展开更多
关键词 共价有机框架 构建策略 C—H活化
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中药植物紫草天然产物的生物合成及其功能研究进展 被引量:17
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作者 林红燕 王煊 +7 位作者 何聪 周紫玲 杨旻恺 文钟灵 韩洪苇 陆桂华 戚金亮 杨永华 《遗传》 CAS CSCD 北大核心 2021年第5期459-472,共14页
紫草为我国传统的重要药用植物资源,其根部代谢产生的紫红色萘醌类天然产物—紫草素及其衍生物,临床上常被用于治疗疮疡和皮肤炎症。数十年来,紫草因具高效的多重生物活性、药理作用、良好的临床疗效、较高的利用价值,引起了国内外研究... 紫草为我国传统的重要药用植物资源,其根部代谢产生的紫红色萘醌类天然产物—紫草素及其衍生物,临床上常被用于治疗疮疡和皮肤炎症。数十年来,紫草因具高效的多重生物活性、药理作用、良好的临床疗效、较高的利用价值,引起了国内外研究者的重视与关注,正由于此种原因,其野生植物种质资源常遭到大量采挖,生长环境受到严重威胁。随着植物天然产物的生物合成、分子代谢及其生物技术的发展,药用植物天然产物生物活性功能与药理作用研究手段的不断创新,紫草的生物合成途径和相关调控基因的研究取得了显著的进展,紫草素药理作用及其机制得到深入阐明或解析,极大地推进了紫草素的基础性研究及其临床应用开发的进程。本文从紫草分类、紫草素的结构与组成及其生物合成途径、调控紫草素生物合成代谢的功能相关基因以及紫草素生物活性与药理功能等方面综述了相关研究进展,并对未来可能的发展趋势进行了展望,以期为促进我国重要中药材源的药用天然产物的深度挖掘与开发提供有益参考,推动我国传统中药学的现代化发展。 展开更多
关键词 紫草 紫草素 生物合成 基因调控 药理活性
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食管癌术后淋巴结状态对术后辅助治疗选择的预测价值 被引量:6
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作者 宋春洋 祝淑钗 +6 位作者 王旋 高丝娜 赵彦 许金蕊 李曙光 闫可 张雪原 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第2期66-71,共6页
目的:分析食管癌患者术后的淋巴结状态对术后辅助治疗方案选择的预测价值及与预后的关系。方法:分析2007年1月至2010年12月河北医科大学第四医院354例食管癌根治术后患者,对其淋巴结各相关参数与术后辅助治疗进行预后分析。单因素生存... 目的:分析食管癌患者术后的淋巴结状态对术后辅助治疗方案选择的预测价值及与预后的关系。方法:分析2007年1月至2010年12月河北医科大学第四医院354例食管癌根治术后患者,对其淋巴结各相关参数与术后辅助治疗进行预后分析。单因素生存分析采用Kaplan-Meier法和Log-rank检验,多因素生存分析采用Cox回归模型。结果:全组患者1、3、5年生存率分别为84.46%、64.12%和54.06%,中位生存期为86.49个月。N0、N1、N2、N3期患者的5年生存率分别为93.13%、55.50%、19.80%和3.45%,不同N分期之间的差异具有统计学意义(χ^2=225.161,P<0.001)。通过ROC曲线获取阳性淋巴结数目与清扫总淋巴结数目的比值(LNR)为分组界值8.51%将其分为两组并进行生存分析,LNR≤8.51%组及LNR>8.51%组患者的5年生存率分别为81.63%和23.40%,两组之间的差异具有统计学意义(χ^2=143.504,P<0.001)。单因素预后分析显示术后T分期、N分期、LNR、阴性淋巴结数目与患者的生存预后均相关(均P<0.05)。多因素预后分析显示术后N分期、LNR为生存预后的独立影响因素(均P<0.05)。N2组及LNR>8.51%组接受术后辅助治疗的患者生存显著优于单纯手术组(χ^2=12.609,P<0.001;χ^2=13.171,P<0.001)。联合N分期及LNR进行分析,在LNR>8.51%组的N2期患者接受术后辅助治疗组生存显著优于单纯手术组(χ^2=12.609,P<0.001)。结论:LNR可以协同N分期更好地提示预后并指导食管癌根治术后患者辅助治疗的选择。对N2期同时伴有高LNR的患者应该积极选择术后辅助治疗。 展开更多
关键词 食管恶性肿瘤 手术 淋巴结状态 术后辅助治疗 预后
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Assessing carbon stock and BVOCs emissions from dominant tree species in Beijing
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作者 Luxi wang xuan wang +2 位作者 Xiaoxiu Lun Qiang wang Yanshan Gao 《Journal of Environmental Sciences》 2025年第10期1-13,共13页
Urban areas face environmental pollution and greenhouse emissions challenges,demand collaborative efforts to mitigation.Urban forests play a crucial role in absorbing CO_(2) emissions and contributing to carbon seques... Urban areas face environmental pollution and greenhouse emissions challenges,demand collaborative efforts to mitigation.Urban forests play a crucial role in absorbing CO_(2) emissions and contributing to carbon sequestration potential,but they also release biogenic volatile organic compounds(BVOCs),which contribute to the formation of tropospheric ozone and secondary organic aerosols(SOA).This study aimed to understand the role of urban forests in carbon stock and BVOCs emission by establishing optimal biomass models for six typical tree species(Robinia pseudoacacia,Quercus,Populus,Pinus tabulaeformis,Betula platyphylla,and Larix gmelinii)in Beijing.Biomass models were developed using field surveys and remote sensing data,with R^(2) values ranging from 0.364 to 0.921.Applying these models to forest resource inventory data,carbon stock and BVOCs emission models were constructed.In 2021,the total carbon stock for these pure forest tree species was estimated at 5.638 million tons,with a carbon density of 58.86 t/ha.The carbon density ranking for pure forest tree species was:Robinia pseudoacacia>Populus tomentosa>Betula platyphylla>Quercus Linn>Pinus tabulaeformis>Larix gmelinii.Total BVOCs emission in 2021 from the studied species were calculated at 25,789.72 t,with an average emission of 0.27 t/ha.Populus tomentosa had the highest BVOCs emission per unit area,followed by Robinia pseudoacacia,and Larix gmelinii had the smallest.Betula platyphylla and Robinia pseudoacacia were identified as species with high carbon stock and low BVOCs emissions in Beijing,offering insights for future urban forest planning and eco-friendly urban environment development strategies. 展开更多
关键词 Urban forest Biomass remote sensing Carbon stock Biogenic volatile organic compounds(BVOCs) Biomass models Environmental planning
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Neurophysiological mechanisms of electroacupuncture in regulating pancreatic function and adipose tissue expansion
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作者 Yun Liu Zhi Yu +9 位作者 xuan wang Ming-Qian Yuan Meng-Jiang Lu Mei-Rong Gong Qian Li You-Bing Xia Guan-Hu Yang Bin Xu Gerhard Litscher Tian-Cheng Xu 《World Journal of Diabetes》 2025年第5期254-270,共17页
BACKGROUND Electroacupuncture(EA)has been recognized for its beneficial effects on glucolipid metabolism,potentially through the regulation of sensory nerve coordination.The expandability of peripancreatic adipose tis... BACKGROUND Electroacupuncture(EA)has been recognized for its beneficial effects on glucolipid metabolism,potentially through the regulation of sensory nerve coordination.The expandability of peripancreatic adipose tissue(PAT)is implicated in the transition from obesity to type 2 diabetes mellitus(T2DM).However,the specific pancreatic responses to EA require further elucidation.AIM To investigate the influence of EA on pancreatic glucolipid reduction level in a high-fat diet(HFD)rat model.METHODS To delineate the precise pathway through which EA mediates interactions bet ween PAT and islets,we assessed the expression levels of NGF,TRPV1,insulin,as well as other proteins in the pancreas and PAT.This approach enabled us to identify the acupoints that are most conducive to optimizing glycolipid metabolism.RESULTS The ST25,LI11 and ST37 groups attenuated HFD-induced obesity and insulin resistance(IR)to distinct degrees,with ST25 group having the greatest effect.EA at ST25 was found to modify the local regulatory influence of PAT on the pancreatic intrinsic nervous system.Specifically,EA at ST25 obviously activated the TRPV1-CGRP-islet beta cell pathway,contributing to the relief of glucolipid metabolic stress.The beneficial effects were abrogated following the chemical silencing of TRPV1 sensory afferents,confirming their indispensable role in EA-mediated regulation of islet and PAT function.Furthermore,in TRPV1 knockout mice,a reduction in PAT inflammation was observed,along with the recovery of islet beta cell function.EA at LI11 and ST37 demonstrated anti-inflammatory properties and helped ameliorate IR.CONCLUSION The PAT ecological niche influenced the progression from obesity to T2DM through various immunometabolic pathways.EA at ST25 could regulate glucolipid metabolism via the TRPV1-CGRP-islet beta cell pathway. 展开更多
关键词 Insulin resistance ELECTROACUPUNCTURE Sensory nerve Transient receptor potential vanilloid 1 receptor Pancreatic beta cell Peripancreatic adipose tissue
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Bidirectional Mendelian randomization and mediation analysis of million-scale data reveal causal relationships between thyroid-related phenotypes,smoking,and lung cancer
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作者 Xiang wang xuan wang +15 位作者 Mengsheng Zhao Lijuan Lin Yi Li Ning Xie Yanru wang Aoxuan wang Xiaowen Xu Can Ju Qiuyuan Chen Jiajin Chen Ruili Hou Zhongwen Zhang David C.Christiani Feng Chen Yongyue Wei Ruyang Zhang 《Journal of Biomedical Research》 2025年第5期441-451,I0001-I0023,共34页
Emerging evidence highlights the role of thyroid hormones in cancer,although findings are controversial.Research on thyroid-related traits in lung carcinogenesis is limited.Using UK Biobank data,we performed bidirecti... Emerging evidence highlights the role of thyroid hormones in cancer,although findings are controversial.Research on thyroid-related traits in lung carcinogenesis is limited.Using UK Biobank data,we performed bidirectional Mendelian randomization(MR)to assess causal associations between lung cancer risk and thyroid dysfunction(hypothyroidism and hyperthyroidism)or functional traits(free thyroxine[FT4]and normal-range thyroid-stimulating hormone[TSH]).Furthermore,in the smoking-behavior-stratified MR analysis,we evaluated the mediating effect of thyroid-related phenotypes on the association between smoking behaviors and lung cancer.We demonstrated significant associations between lung cancer risk and hypothyroidism(hazard ratio[HR]=1.14,95%confidence interval[CI]=1.03–1.26,P=0.009)and hyperthyroidism(HR=1.55,95%CI=1.29–1.87,P=1.90×10^(-6))in the UKB.Moreover,the MR analysis indicated a causal effect of thyroid dysfunction on lung cancer risk(ORinverse variance weighted[IVW]=1.09,95%CI=1.05–1.13,P=3.12×10^(-6)for hypothyroidism;ORIVW=1.08,95%CI=1.04–1.12,P=8.14×10^(-5)for hyperthyroidism).We found that FT4 levels were protective against lung cancer risk(ORIVW=0.93,95%CI=0.87–0.99,P=0.030).Additionally,the stratified MR analysis demonstrated distinct causal effects of thyroid dysfunction on lung cancer risk among smokers.Hyperthyroidism mediated the effect of smoking behaviors,especially the age of smoking initiation(17.66%mediated),on lung cancer risk.Thus,thyroid dysfunction phenotypes play causal roles in lung cancer development exclusively among smokers and act as mediators in the causal pathway from smoking to lung cancer. 展开更多
关键词 HYPOTHYROIDISM HYPERTHYROIDISM lung neoplasms SMOKING CAUSALITY Mendelian randomization analysis
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碳纤维改性聚四氟乙烯的摩擦及振动性能 被引量:8
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作者 杨雪 李少楠 +1 位作者 王轩 胡晓阳 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第5期60-65,73,共7页
文中研究了20%的碳纤维(体积分数)改性聚四氟乙烯在干摩擦和水润滑摩擦条件下的摩擦系数、磨损性能和摩擦振动性能。结果表明:(1)在干摩擦下,随着线速度增加,摩擦界面生成大量的热,黏着磨损和磨粒磨损严重,表面越来越粗糙,摩擦系数明显... 文中研究了20%的碳纤维(体积分数)改性聚四氟乙烯在干摩擦和水润滑摩擦条件下的摩擦系数、磨损性能和摩擦振动性能。结果表明:(1)在干摩擦下,随着线速度增加,摩擦界面生成大量的热,黏着磨损和磨粒磨损严重,表面越来越粗糙,摩擦系数明显变大,摩擦振动加速度增加。而在水润滑条件下,随着线速度增加,摩擦界面间形成了一层水润滑膜,使摩擦系数降低,另外由于转速增加,使流噪声增加,从而使振动增加。(2)在干摩擦下,随着比压增加,摩擦系数和摩擦振动变化较大,而在水润滑条件下,随着比压增加,摩擦系数和摩擦振动变化较小。(3)干摩擦时,碳纤维增强聚四氟乙烯复合材料在不同比压下的磨损机理主要是磨粒磨损和黏着磨损;水润滑条件下,碳纤维增强聚四氟乙烯复合材料在高比压下的磨损机理主要是黏着磨损。因此,碳纤维改性聚四氟乙烯复合材料应该在水润滑条件下应用有利于提高耐磨性,降低摩擦系数和摩擦振动。 展开更多
关键词 碳纤维 聚四氟乙烯 摩擦系数 磨损 摩擦振动
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Ultrahigh specific surface area mesoporous perovskite oxide nanosheets with rare-earth-enhanced lattice oxygen participation for superior water oxidation
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作者 Biao wang Xiangrui Wu +9 位作者 Suyue Jia Jiayi Tang Hao Wu xuan wang Shengyong Gao Hao Li Haijiao Lu Gengtao Fu Xiangkang Meng Shaochun Tang 《Journal of Materials Science & Technology》 2025年第24期255-261,共7页
Perovskite oxides(ABO_(3))are thought to be promising electrocatalysts for oxygen evolution reaction(OER),but their specific surface area(SSA)is too low(usually<10 m^(2) g^(−1)).Developing advanced ABO_(3) electroc... Perovskite oxides(ABO_(3))are thought to be promising electrocatalysts for oxygen evolution reaction(OER),but their specific surface area(SSA)is too low(usually<10 m^(2) g^(−1)).Developing advanced ABO_(3) electrocatalysts with high SSA and optimized structure is of great significance but remains a tremendous challenge.Herein,we propose a general strategy for fabrication of mesoporous perovskite oxide nanosheets(MPONs)with controllable atomic doping via self-sacrificial template-induced nanostructure modulation.A variety of MPONs including LaFeO_(3),A-site-doped LaFeO_(3)(A-LaFeO_(3),where A is Pr,Nd,Sm,Eu,or Gd)and B-site-doped LaFeO_(3)(B-LaFeO_(3),where B is Mn,Co,Ni,Cu,or Zn)have been achieved.Interestingly,it is discovered that the catalytic activities of A-LaFeO_(3) MPONs as OER catalysts are overall higher than those of B-LaFeO_(3) ones.Especially,the screened Eu-LaFeO_(3) MPONs only require a low overpotential of 267 mV at 10 mA cm^(−2),outperforming most reported perovskite oxides.The superior catalytic activity of Eu-LaFeO_(3) MPONs is attributed to their favorable porous structure,which increases the density of active sites,and enhanced lattice oxygen participation,which improves the intrinsic activity.This study provides guidance for the design and controlled synthesis of advanced rare-earth-doped MPONs with ultrahigh SSA for enhanced electrocatalysis. 展开更多
关键词 MESOPOROUS Perovskite oxides Rare-earth doping Oxygen evolution reaction ELECTROCATALYSTS
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P2-type low-cost and moisture-stable cathode for sodium-ion batteries
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作者 xuan wang Peng Sun +2 位作者 Siteng Yuan Lu Yue Yufeng Zhao 《Chinese Chemical Letters》 2025年第5期679-684,共6页
Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries;however,they face significant challenges,including structural degradation when charged at high cutoff voltages and structural changes u... Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries;however,they face significant challenges,including structural degradation when charged at high cutoff voltages and structural changes upon storing in a humid atmosphere.In response to these issues,we have designed an oxide with co-doping of Cu and Al which can balance both cost and structural stability.The redox reaction of Cu^(2+/3+)can provide certain charge compensation,and the introduction of Al can further suppress the Jahn-Teller effect of Mn,thereby achieving superior long-term cycling performance.The ex-situ XRD testing indicates that Cu/Al co-doping can effectively suppress the phase transition of P2-O2 at high voltage,thereby explaining the improvement in electrochemical performance.DFT calculations reveal a high chemical tolerance to moisture,with lower adsorption energy for H_(2)O compared to pure Na_(0.67)Cu_(0.25)Mn_(0.75)O_(2).A representative Na_(0.67)Cu_(0.20)Al_(0.05)Mn_(0.75)O_(2)cathode demonstrates impressive reversible capacities of 148.7 mAh/g at 0.2 C,along with a remarkable capacity retention of 79.1%(2 C,500 cycles). 展开更多
关键词 Cathode material P2 phase Moisture sensitivity LOW-COST Sodium-ion batteries
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Threat-related attentional bias in subjects with different looming cognitive styles:Evidence based on eye-tracking study
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作者 xuan wang Shuai Chen +1 位作者 Bin Tian Wen-Peng Cai 《World Journal of Psychiatry》 2025年第10期297-308,共12页
BACKGROUND Although extensive research has investigated attentional biases based on the looming vulnerability model of anxiety,the characteristics of attentional biases in individuals with looming cognitive styles(LCS... BACKGROUND Although extensive research has investigated attentional biases based on the looming vulnerability model of anxiety,the characteristics of attentional biases in individuals with looming cognitive styles(LCS)remain incompletely elucidated.No prior eye-tracking studies have examined the spatiotemporal dynamics of their threat-related attentional preferences.AIM To investigate the nature and temporal pattern of attentional biases toward threat stimuli in individuals exhibiting different levels of LCS using eye-tracking technology.METHODS A total of 212 participants were stratified according to their Looming Maladaptive Style Questionnaire scores.From the high and low scoring subgroups,35 participants were randomly selected for an eye-tracking experiment using a classic dot-probe paradigm featuring threat and neutral images.Four eye-tracking metrics,including first fixation latency,first fixation duration,total fixation duration,and fixation count,were analyzed to assess detection speed,attentional orienting,initial maintenance/avoidance,and overall engagement.RESULTS Distinct attentional bias patterns were observed between high and low LCS groups.High LCS individuals exhibited a vigilance-avoidance pattern characterized by initial vigilance toward threat stimuli(evidenced by faster detection and preferential orienting),followed by attentional avoidance,alongside sustained attention maintenance to threat.CONCLUSION These findings reveal a temporal dissociation between early vigilance and later avoidance during threat processing in high LCS individuals,providing novel empirical evidence to refine models of cognitive vulnerability and attentional dynamics in threat perception. 展开更多
关键词 ANXIETY Attentional bias Looming cognitive styles College students Eye-tracking study
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Electroacupuncture alleviates diabetic peripheral neuropathy through modulating mitochondrial biogenesis and suppressing oxidative stress
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作者 Chong-Xi Yuan xuan wang +3 位作者 Yun Liu Tian-Cheng Xu Zhi Yu Bin Xu 《World Journal of Diabetes》 2025年第2期133-150,共18页
BACKGROUND Peripheral neuropathy caused by diabetes is closely related to the vicious cycle of oxidative stress and mitochondrial dysfunction resulting from metabolic abnormalities.The effects mediated by the silent i... BACKGROUND Peripheral neuropathy caused by diabetes is closely related to the vicious cycle of oxidative stress and mitochondrial dysfunction resulting from metabolic abnormalities.The effects mediated by the silent information regulator type 2 homolog-1(SIRT1)/peroxisome proliferator-activated receptor-gamma coactivator-1α(PGC-1α)axis present new opportunities for the treatment of type 2 diabetic peripheral neuropathy(T2DPN),potentially breaking this harmful cycle.AIM To validate the effectiveness of electroacupuncture(EA)in the treatment of T2DPN and investigate its potential mechanism based on the SIRT1/PGC-1αaxis.METHODS The effects of EA were evaluated through assessments of metabolic changes,morphological observations,and functional examinations of the sciatic nerve,along with measurements of inflammation and oxidative stress.Proteins related to the SIRT1/PGC-1αaxis,involved in the regulation of mitochondrial biogenesis and antioxidative stress,were detected in the sciatic nerve using Western blotting to explain the underlying mechanism.A counterevidence group was created by injecting a SIRT1 inhibitor during EA intervention to support the hypothesis.RESULTS In addition to diabetes-related metabolic changes,T2DPN rats showed significant reductions in pain threshold after 9 weeks,suggesting abnormal peripheral nerve function.EA treatment partially restored metabolic control and reduced nerve damage in T2DPN rats.The SIRT1/PGC-1αaxis,which was downregulated in the model group,was upregulated by EA intervention.The endogenous antioxidant system related to the SIRT1/PGC-1αaxis,previously inhibited in diabetic rats,was reactivated.A similar trend was observed in inflammatory markers.When SIRT1 was inhibited in diabetic rats,these beneficial effects were abolished.CONCLUSION EA can alleviate the symptoms of T2DNP in experimental rats,and its effects may be related to the mitochondrial biogenesis and endogenous antioxidant system mediated by the SIRT1/PGC-1αaxis. 展开更多
关键词 ELECTROACUPUNCTURE Type 2 diabetic peripheral neuropathy Silent matching type information regulation 2 homolog-1/peroxisome proliferator-activated receptor-gamma coactivator-1αaxis Mitochondria biogenesis Oxidative stress
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