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Advances in fecal microbiota transplantation for the treatment of Helicobacter pylori infection
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作者 Wei Fu yu li +3 位作者 Hai-Yan Bi Xiao-yue Wu Yan Geng Hu-lin Wang 《Infectious Diseases Research》 2026年第1期4-9,共6页
Helicobacter pylori(H.pylori)infection remains a pivotal driver of chronic gastritis,peptic ulcer,gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer,yet its eradication is increasingly frustrated by... Helicobacter pylori(H.pylori)infection remains a pivotal driver of chronic gastritis,peptic ulcer,gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer,yet its eradication is increasingly frustrated by climbing antibiotic resistance and intolerable side-effects of standard triple or quadruple therapies.In recent years,fecal microbiota transplantation(FMT),a strategy that reconstructs the gut ecosystem by introducing a healthy donor microbiome,has emerged as a novel adjunct or alternative.By competitively excluding H.pylori,reinforcing mucosal barrier integrity,modulating host immunity and secreting bacteriocins,FMT can raise eradication rates,relieve dyspeptic symptoms and lower recurrence.This review synthesizes up-to-date pre-clinical,pilot and controlled clinical data,dissects underlying mechanisms,compares delivery routes,donor screening protocols and safety profiles,and discusses regulatory,ethical and standardization hurdles that must be overcome before large-scale clinical application. 展开更多
关键词 fecal microbiota transplantation Helicobacter pylori gut microbiota infection treatment mechanism research
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Antidepressant effects of Peiyuan Jieyu formula in a mouse model of chronic stress in conjunction with lipopolysaccharide-induced depression 被引量:1
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作者 Qin Tang yu li +3 位作者 Tao Yang Xiaoxu Fan lina li Hongsheng Chang 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期111-119,共9页
Objective:To explore the mechanism of the Peiyuan Jieyu formula in treating depression by assessing its impact on a lipopolysaccharide-induced(LPS-induced)depression mouse model.Methods:We created a mouse model of dep... Objective:To explore the mechanism of the Peiyuan Jieyu formula in treating depression by assessing its impact on a lipopolysaccharide-induced(LPS-induced)depression mouse model.Methods:We created a mouse model of depression by exposing mice that had previously received chronic stress to intraperitoneal LPS injections.The mice were divided into the following groups:control,model,fluoxetine,Tiansi Yin,Sini powder,and low-,medium-,and high-dose Peiyuan Jieyu formula groups.Forced swim and tail suspension tests were used to assess the efficacy of the depression(despair)model,and weight gain rates were also measured.Furthermore,serum levels of various depression and inflammation-associated molecules,including tumor necrosis factor-a(TNF-a),interferon-γ(IFN-γ),tryptophan,5-hydroxytryptamine,kynurenine(KYN),and kynurenic acid(KA)were assessed.Furthermore,the expression levels of ionic calcium-binding adaptor molecule-1(IBA-1)and indoleamine 2,3-dioxygenase(IDO)mRNA in hippocampal microglia were measured.Results:The model group displayed greater despair-associated immobility,which was shortened in response to various doses of Peiyuan Jieyu formula.Furthermore,formula administration significantly reduced serum TNF-a levels and hippocampal IDO mRNA expression.The high formula dose also reduced IFN-γand IBA-1 levels,the latter was also decreased in response to the medium formula dose.However,the low formula dose reduced serum KYN level and KYN/tryptophan(TRP)and KYN/KA ratios.Conclusion:The Peiyuan Jieyu formula holds immense potential in treating depression in a mouse model,potentially inhibiting inflammation and improving TRP-KYN metabolic disorders. 展开更多
关键词 Peiyuan Jieyu formula DEPRESSION Chronic stress LIPOPOLYSACCHARIDE Inflammation Tryptophan pathway
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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw 被引量:2
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作者 Meng-Ying liu Zhe-Hui Zhang +7 位作者 Xue-Qi Wang Qian Sun Chen Zhang yu li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi yuan 《Green Energy & Environment》 SCIE EI CAS 2025年第1期161-172,共12页
Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin f... Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%. 展开更多
关键词 Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural
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Shenlian Extract Protects against Ultrafine Particulate Matter-Aggravated Myocardial Ischemic Injury by Inhibiting Inflammation and Cell Apoptosis 被引量:1
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作者 Shuiqing Qu Yan liang +7 位作者 Shuoqiu Deng yu li yue Dai Chengcheng liu Tuo liu Luqi Wang lina Chen yujie li 《Biomedical and Environmental Sciences》 2025年第2期206-218,共13页
Objective Emerging evidence suggests that exposure to ultrafine particulate matter(UPM,aerodynamic diameter<0.1μm)is associated with adverse cardiovascular events.Previous studies have found that Shenlian(SL)extra... Objective Emerging evidence suggests that exposure to ultrafine particulate matter(UPM,aerodynamic diameter<0.1μm)is associated with adverse cardiovascular events.Previous studies have found that Shenlian(SL)extract possesses anti-inflammatory and antiapoptotic properties and has a promising protective effect at all stages of the atherosclerotic disease process.In this study,we aimed to investigated whether SL improves UPM-aggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis.Methods We established a mouse model of MI+UPM.Echocardiographic measurement,measurement of myocardialinfarct size,biochemical analysis,enzyme-linked immunosorbent assay(ELISA),histopathological analysis,Transferase dUTP Nick End Labeling(TUNEL),Western blotting(WB),Polymerase Chain Reaction(PCR)and so on were used to explore the anti-inflammatory and antiapoptotic effects of SL in vivo and in vitro.Results SL treatment can attenuate UPM-induced cardiac dysfunction by improving left ventricular ejection fraction,fractional shortening,and decreasing cardiac infarction area.SL significantly reduced the levels of myocardial enzymes and attenuated UPM-induced morphological alterations.Moreover,SL significantly reduced expression levels of the inflammatory cytokines IL-6,TNF-α,and MCP-1.UPM further increased the infiltration of macrophages in myocardial tissue,whereas SL intervention reversed this phenomenon.UPM also triggered myocardial apoptosis,which was markedly attenuated by SL treatment.The results of in vitro experiments revealed that SL prevented cell damage caused by exposure to UPM combined with hypoxia by reducing the expression of the inflammatory factor NF-κB and inhibiting apoptosis in H9c2 cells.Conclusion Overall,both in vivo and in vitro experiments demonstrated that SL attenuated UPMaggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis.The mechanisms were related to the downregulation of macrophages infiltrating heart tissues. 展开更多
关键词 Ultrafine particulate matter Shenlian extract INFLAMMATION Apoptosis MACROPHAGE
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不同温度循环作用下花岗岩的渗透性
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作者 余莉 赵琨 +2 位作者 周杰 李沐宸 李皓楠 《河北大学学报(自然科学版)》 北大核心 2026年第1期13-21,共9页
为探究高温循环对岩石内部结构的影响,本文开展了不同温度循环作用下花岗岩的渗透性实验,分析了经历不同温度循环处理后岩样孔隙率与渗透率的变化规律,并通过回归分析建立了纵波波速与孔隙率、渗透率之间的关系.结果表明:1)在1~3次热循... 为探究高温循环对岩石内部结构的影响,本文开展了不同温度循环作用下花岗岩的渗透性实验,分析了经历不同温度循环处理后岩样孔隙率与渗透率的变化规律,并通过回归分析建立了纵波波速与孔隙率、渗透率之间的关系.结果表明:1)在1~3次热循环中,花岗岩孔隙率与渗透率均有所降低,且变化服从对数关系;随着循环增加至5~10次,二者下降速率逐渐减缓,该特征为深部地热资源的长期开发提供了有利条件.2)不同温度循环下,花岗岩纵波波速与渗透率、孔隙率均呈现对数关系.随循环次数增加,三者关系由1~3次循环时的对数关系逐渐转变为5~10次循环时的线性关系.因此,可通过测量纵波波速来无损估算花岗岩的孔隙率与渗透率.3)对400℃热循环10次后的花岗岩进行CT扫描与SEM电镜观测发现,孔隙结构中出现碎屑颗粒,表明温度循环作用导致岩石内部结构损伤.该现象揭示了深部地热能开采过程中岩石物理性质劣化的机制,为深部地热资源开发提供了理论依据. 展开更多
关键词 花岗岩 高温循环 物理性质 渗透率 微观结构
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Solidworks应用于《机械设计课程设计》课程教学 被引量:10
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作者 余丽 伍哲 +1 位作者 施冠羽 郭文勇 《机械设计与制造》 北大核心 2024年第1期20-22,29,共4页
在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现... 在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现了传动装置的运动仿真,完成了该锚机系缆装置的模拟设计,锻炼了学生的软件使用技能,增强了学生对理论知识的深入理解和应用,激发了学生对机械课程深入学习的兴趣,提高了学生的机械设计水平,同时有助于培养学生工程实践和综合应用能力,达到了预期的教学效果。 展开更多
关键词 机械设计课程设计 SOLIDWORKS 计算机辅助设计 课程教学 虚拟仿真 装配设计
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Corrigendum to“Multi-activity ferruginated carbon quantum dots nanozyme improves wheat seedling growth and Cd tolerance”[Crop J.13(2025)510–523]
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作者 Zhiwei Lu yu li +9 位作者 Keyu Chen Songyue Chai Gehong Su Chun Wu Mengmeng Sun Yanying Wang Shiling Feng Ming Hao Hanbing Rao Dengcai liu 《The Crop Journal》 2025年第5期1654-1654,共1页
The authors regret to report some missing information in the synthetic reagents and associated changes of the paper.On page 511,the author information reads:“5.0 mmol of citric acid(C_(6)H_(8)O_(7)),5.0 mmol of ferri... The authors regret to report some missing information in the synthetic reagents and associated changes of the paper.On page 511,the author information reads:“5.0 mmol of citric acid(C_(6)H_(8)O_(7)),5.0 mmol of ferric chloride hexahydrate(FeCl_(3)·6H_(2)O),and 10.0 mmol of o-phenylenediamine(C_(6)H_(8)N_(2))were combined with 40 mL of deionized water and magnetically stirred until fully dissolved.” 展开更多
关键词 magnetically stirred synthetic reagents associated changes carbon quantum dots ferric chloride hexahydrate fecl h o multi activity deionized water ferruginated nanozyme
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A two-stage scheduling algorithm based on pointer network with attention mechanism for micro-nano Earth observation satellite constellation
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作者 Hai li yuanhao liU +5 位作者 Boyu DENG Yongjun li Xin li yu li Taijiang ZHANG Shanghong ZHAO 《Chinese Journal of Aeronautics》 2025年第8期433-448,共16页
Micro-nano Earth Observation Satellite(MEOS)constellation has the advantages of low construction cost,short revisit cycle,and high functional density,which is considered a promising solution for serving rapidly growin... Micro-nano Earth Observation Satellite(MEOS)constellation has the advantages of low construction cost,short revisit cycle,and high functional density,which is considered a promising solution for serving rapidly growing observation demands.The observation Scheduling Problem in the MEOS constellation(MEOSSP)is a challenging issue due to the large number of satellites and tasks,as well as complex observation constraints.To address the large-scale and complicated MEOSSP,we develop a Two-Stage Scheduling Algorithm based on the Pointer Network with Attention mechanism(TSSA-PNA).In TSSA-PNA,the MEOS observation scheduling is decomposed into a task allocation stage and a single-MEOS scheduling stage.In the task allocation stage,an adaptive task allocation algorithm with four problem-specific allocation operators is proposed to reallocate the unscheduled tasks to new MEOSs.Regarding the single-MEOS scheduling stage,we design a pointer network based on the encoder-decoder architecture to learn the optimal singleMEOS scheduling solution and introduce the attention mechanism into the encoder to improve the learning efficiency.The Pointer Network with Attention mechanism(PNA)can generate the single-MEOS scheduling solution quickly in an end-to-end manner.These two decomposed stages are performed iteratively to search for the solution with high profit.A greedy local search algorithm is developed to improve the profits further.The performance of the PNA and TSSA-PNA on singleMEOS and multi-MEOS scheduling problems are evaluated in the experiments.The experimental results demonstrate that PNA can obtain the approximate solution for the single-MEOS scheduling problem in a short time.Besides,the TSSA-PNA can achieve higher observation profits than the existing scheduling algorithms within the acceptable computational time for the large-scale MEOS scheduling problem. 展开更多
关键词 Micro-nano earth observation satellite Observation scheduling Large-scale scheduling Two-stage optimization Pointer network Attention mechanism
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Long lifespan Li-Se battery:Advances,challenges and prospects
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作者 Hongyan li Thomas L.Madanu +6 位作者 Tarek Barakat Wen-Da Dong Alexandru Vlad Xikun Zhang Cheng-Bin Jin yu li Bao-lian Su 《Journal of Energy Chemistry》 2025年第3期712-733,共22页
Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the po... Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the popular sulfur cathode.However,its practical application still faces great challenges,especially the rapid capacity decay triggered by the loss of active Se species.A comprehensive review to uncover the in-depth failure mechanism and provide targeted solutions to promote the stable operation of Li-Se batteries is urgently needed.This review systematically summarizes the strategies in the new perspective,focusing on the optimization of Se utilization in Li-Se batteries by keeping a high Se maintenance in the cathode and accelerating the electrochemical kinetics of lithium polyselenides(LiPSe)conversion.On the basis of stru ctural design and Li_(2)Se active material introduction to accommodate volume expansion,blocking s huttle transport of LiPSe by physical/chemical adsorption,bonding Se with polymers or cathode electrolyte interphase(CEI)construction,and catalytic design to accelerate the conversion of LiPSe,different strategies for improving the utilization of Se have been evaluated and discussed.To address the inevitable loss of Se,prospects on inactive Se reactivation and Li protection are detailedly proposed and analyzed referring to the chemistry and corrosion science.Additionally,the perspectives on the future design and comprehensive parameter evaluations for the optimization of Li-Se batteries are recommended.This review comprehensively explains the causes and solutions of capacity fading and provides potential efforts for lifespan expansion of batteries,shedding light on the future development of Li-Se batteries. 展开更多
关键词 Lithium-selenium battery Shuttle effect Adsorption Catalysis Inactive Se reactivation Li protection
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A Dynamic Knowledge Base Updating Mechanism-Based Retrieval-Augmented Generation Framework for Intelligent Question-and-Answer Systems
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作者 yu li 《Journal of Computer and Communications》 2025年第1期41-58,共18页
In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilizati... In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilization of this information. This study proposes a novel framework for intelligent Question-and-Answer (Q&A) systems based on Retrieval-Augmented Generation (RAG) to address these issues. The system efficiently acquires domain-specific knowledge by leveraging external databases, including Relational Databases (RDBs) and graph databases, without additional fine-tuning for Large Language Models (LLMs). Crucially, the framework integrates a Dynamic Knowledge Base Updating Mechanism (DKBUM) and a Weighted Context-Aware Similarity (WCAS) method to enhance retrieval accuracy and mitigate inherent limitations of LLMs, such as hallucinations and lack of specialization. Additionally, the proposed DKBUM dynamically adjusts knowledge weights within the database, ensuring that the most recent and relevant information is utilized, while WCAS refines the alignment between queries and knowledge items by enhanced context understanding. Experimental validation demonstrates that the system can generate timely, accurate, and context-sensitive responses, making it a robust solution for managing complex business logic in specialized industries. 展开更多
关键词 Retrieval-Augmented Generation Question-and-Answer Large Language Models Dynamic Knowledge Base Updating Mechanism Weighted Context-Aware Similarity
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Robust protective SiO_(x) and dual carbon layers assisted Si anode achieving rapid kinetics for ultra-fast stable Li^(+) storage
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作者 Wen-Hua Shi liang Wu +9 位作者 Zhong-Bu Qin Ya-Wen Tian Yao liu Wen-Bei yu Run-Tian Zheng Jing liu Zhi-Yi Hu yu li li-Hua Chen Bao-lian Su 《Journal of Energy Chemistry》 2025年第11期466-475,I0012,共11页
Silicon(Si)has gained popularity as a potential anodic material for Li-ion batteries(LIBs)due to its large theoretical capacity.However,low conductivity,large volume expansion,and side reactions during alloying and de... Silicon(Si)has gained popularity as a potential anodic material for Li-ion batteries(LIBs)due to its large theoretical capacity.However,low conductivity,large volume expansion,and side reactions during alloying and de-alloying lead to poor cyclic and bad high-rate performance,which has severely hindered its practical large-scale application.Herein,a novel stamen-structured Si-based anode material with a protective SiO_(x)layer and dual carbon layers(Si@SiO_(x)/C@C)is designed for high-performance LIBs.The protective SiO_(x)layer reduces side reactions and dual carbon layers enhance charge transport to improve reaction kinetics,while the unique structure provides buffering space for volume expansion.Such Si@SiO_(x)/C@C anode demonstrates impressive Li storage properties for a half-battery,including a discharge capacity of 2935 mA h g^(-1)at a current density 0.1 A g^(-1),cyclic performance(814 mA h g^(-1)at 2 A g^(-1)over 500 cycles and 988 mA h g^(-1)over 200 cycles at 1 A g^(-1))and a rate performance(609 mA h g^(-1)at 5 A g^(-1)).It also maintains a high reversible capacity of 131 mA h g^(-1)at 0.25 C after100 cycles for a full battery.This work provides insights into the novel design of multiple protective layers on Si-based anode materials for fast-charging and highly stable LIBs. 展开更多
关键词 Li-ion batteries Silicon anode Protective SiO_(x) Dual carbon layers Reaction kinetics
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Hybrid CO_(2) thermal system for post-steam heavy oil recovery:Insights from microscopic visualization experiments and molecular dynamics simulations
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作者 Ning Lu Xiaohu Dong +4 位作者 Haitao Wang Huiqing liu Zhangxin Chen yu li Deshang Zeng 《Energy Geoscience》 2025年第2期233-248,共16页
The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments... The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments and molecular dynamics(MD)simulations,this study investigates the microscopic enhanced oil recovery(EOR)mechanisms underlying residual oil removal using hybrid CO_(2) thermal systems.Based on the experimental models for the occurrence of heavy oil,this study evaluates the performance of hybrid CO_(2) thermal systems under various conditions using MD simulations.The results demonstrate that introducing CO_(2) molecules into heavy oil can effectively penetrate and decompose dense aggregates that are originally formed on hydrophobic surfaces.A stable miscible hybrid CO_(2) thermal system,with a high effective distribution ratio of CO_(2),proficiently reduces the interaction energies between heavy oil and rock surfaces,as well as within heavy oil.A visualization analysis of the interactions reveals that strong van der Waals(vdW)attractions occur between CO_(2) and heavy oil molecules,effectively promoting the decomposition and swelling of heavy oil.This unlocks the residual oil on the hydrophobic surfaces.Considering the impacts of temperature and CO_(2) concentration,an optimal gas-to-steam injection ratio(here,the CO_(2):steam ratio)ranging between 1:6 and 1:9 is recommended.This study examines the microscopic mechanisms underlying the hybrid CO_(2) thermal technique at a molecular scale,providing a significant theoretical guide for its expanded application in EOR. 展开更多
关键词 Heavy oil Hybrid CO_(2)thermal system Microscopic visualization experiment Molecular dynamics simulation Microscopic mechanism
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Multi-activity ferruginated carbon quantum dots nanozyme improves wheat seedling growth and Cd tolerance
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作者 Zhiwei Lu yu li +9 位作者 Keyu Chen Songyue Chai Gehong Su Chun Wu Mengmeng Sun Yanying Wang Shiling Feng Ming Hao Hanbing Rao Dengcai liu 《The Crop Journal》 2025年第2期510-523,共14页
Excessive accumulation of cadmium (Cd) impairs crop growth by inducing oxidative damage through the generation of reactive oxygen species (ROS). In this study, a biocompatible ferruginated carbon quantum dots (Fe-CQDs... Excessive accumulation of cadmium (Cd) impairs crop growth by inducing oxidative damage through the generation of reactive oxygen species (ROS). In this study, a biocompatible ferruginated carbon quantum dots (Fe-CQDs) nanozyme is developed to target ROS, thereby reducing oxidative damage and improving the absorption and transfer of Cd ions in wheat. Notably, Fe-CQDs exhibit multi-enzyme activities mimicking peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD), enabling effective neutralization of active species such as hydroxyl radicals (•OH), hydrogen peroxide (H_(2)O_(2)), and superoxide anions (O_(2)•^(-)). Importantly, root application of 10 mg L^(-1) Fe-CQDs alleviates Cd stress and promotes wheat growth in both hydroponic and soil cultures. Specifically, the levels of O_(2)•^(-), H_(2)O_(2), and malondialdehyde (MDA) in leaf tissues decrease, whereas the non-enzyme antioxidant, reduced glutathione (GSH), increases. Cell wall thickness in the Fe-CQDs-treated group is reduced by 42.4% compared with the Cd group. Moreover, Fe-CQDs enhance the expression of genes related to antioxidants, stress resistance, Cd detoxification, and nutrient transport. Transcriptomic and metabolomic analyses show that Fe-CQDs stimulate the production of flavonoids and regulate the activity of metal transporter genes (YSL, ABC, ZIP) to maintain ROS homeostasis. These findings highlight the potential of Fe-CQDs nanozyme platforms in mitigating oxidative damage and enhancing crop growth, offering new insights into the application of nanobiotechnology in agriculture. 展开更多
关键词 Fe-CQDs nanozyme Oxidative damage Wheat seedling Heavy metal stress NANOBIOTECHNOLOGY
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Enhancement of ductility and resistance to hydrogen embrittlement in laser powder-bed fusion Ti−6Al−4V alloy by reversible transformation
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作者 Huan-qi MA yu li +1 位作者 Wei li Chun XU 《Transactions of Nonferrous Metals Society of China》 2025年第12期4101-4117,共17页
To simultaneously enhance the strength−plasticity synergy and resistance to hydrogen embrittlement(HE),the post-annealing treatment was conducted in a laser powder-bed fusion Ti−6Al−4V alloy to introduce reversible tr... To simultaneously enhance the strength−plasticity synergy and resistance to hydrogen embrittlement(HE),the post-annealing treatment was conducted in a laser powder-bed fusion Ti−6Al−4V alloy to introduce reversible transformation.The microstructure,mechanical properties,and HE behavior of the alloy were analyzed by electron back-scattered diffraction,transmission electron microscopy,slow-strain-rate tensile test,hydrogen permeation and thermal desorption spectroscopy.The as-printed sample exhibited high strength but limited elongation and high HE sensitivity.When annealed at 550℃,the elongation was improved but the hydrogen diffusion rate also increased,thus promoting the formation of brittle hydride.When annealed at 750℃,the reversible transformationα'→β→α'occurred and anα'/β/α'sandwich structure formed,thereby enhancing HE resistance(reducing the total elongation loss to 12%)while maintaining high strength(~1116 MPa).The introduction of nanoscaleβ-phase and soft-orientedα'grain significantly inhibited hydride formation and hydrogen-induced crack propagation. 展开更多
关键词 Ti−6Al−4V alloy hydrogen embrittlement strength−ductility synergy POST-ANNEALING reversible transformation
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Assessing the data quality and seismic monitoring capabilities of the Belt and Road GNSS network
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作者 yu li Yinxing Shao +2 位作者 Tan Wang yuebing Wang Hongbo Shi 《Earthquake Science》 2025年第1期56-66,共11页
The Belt and Road global navigation satellite system(B&R GNSS)network is the first large-scale deployment of Chinese GNSS equipment in a seismic system.Prior to this,there have been few systematic assessments of t... The Belt and Road global navigation satellite system(B&R GNSS)network is the first large-scale deployment of Chinese GNSS equipment in a seismic system.Prior to this,there have been few systematic assessments of the data quality of Chinese GNSS equipment.In this study,data from four representative GNSS sites in different regions of China were analyzed using the G-Nut/Anubis software package.Four main indicators(data integrity rate,data validity ratio,multi-path error,and cycle slip ratio)used to systematically analyze data quality,while evaluating the seismic monitoring capabilities of the network based on earthquake magnitudes estimated from high-frequency GNSS data are evaluated by estimating magnitude based on highfrequency GNSS data.The results indicate that the quality of the data produced by the three types of Chinese receivers used in the network meets the needs of earthquake monitoring and the new seismic industry standards,which provide a reference for the selection of equipment for future new projects.After the B&R GNSS network was established,the seismic monitoring capability for earthquakes with magnitudes greater than M_(W)6.5 in most parts of the Sichuan-Yunnan region improved by approximately 20%.In key areas such as the Sichuan-Yunnan Rhomboid Block,the monitoring capability increased by more than 25%,which has greatly improved the effectiveness of regional comprehensive earthquake management. 展开更多
关键词 Belt and Road multi-system GNSS data quality seismic monitoring capability
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SEDline镇静监测下右美托咪定在胸腔镜肺叶切除术病人中的应用 被引量:5
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作者 凌云志 禹莉 +3 位作者 李晓红 梁启胜 孙宜云 杨栋栋 《蚌埠医学院学报》 CAS 2021年第2期162-165,共4页
目的:通过SEDline镇静监测下右美托咪定在胸腔镜肺叶切除术病人中的应用,以期为麻醉选择更为安全有效的方法。方法:选择ASAⅠ或Ⅱ级的胸腔镜肺叶切除术病人20例,采用随机数字表法分为右美托咪定组(D组)和对照组(N组),每组10例。记录2组... 目的:通过SEDline镇静监测下右美托咪定在胸腔镜肺叶切除术病人中的应用,以期为麻醉选择更为安全有效的方法。方法:选择ASAⅠ或Ⅱ级的胸腔镜肺叶切除术病人20例,采用随机数字表法分为右美托咪定组(D组)和对照组(N组),每组10例。记录2组病人麻醉诱导前(T_(0))、切皮时(T_(1))、单肺通气30 min(T_(2))、术毕即刻(T_(3))的平均动脉压(MAP)、心率(HR)、血氧饱和度(SPO 2)、病人状态指数(PSI);记录2组病人术中瑞芬太尼和丙泊酚的用量;以及术后6 h、24 h VAS评分和Ramsay评分。结果:2组病人在T_(1)、T_(2)、T_(3)时间点MAP均降低(P<0.01),HR减慢(P<0.01),PSI均降低(P<0.01)。其中,N组在T_(2)时间点MAP降低较D组更明显(P<0.01),D组在T_(1)时间点HR低于N组(P<0.01),在T_(2)时间点PSI低于N组(P<0.01);术中瑞芬太尼和丙泊酚的用量D组均明显低于N组;在术后6 h VAS评分D组低于N组(P<0.01),术后6 h Ramsay评分D组高于N组(P<0.01)。结论:胸腔镜肺叶切除术病人行右美托咪定联合SEDline镇静监测,术中病人麻醉状态得以控制,血流动力学更加平稳,术后镇静镇痛更加完善,无术后躁动,能对病人的快速康复起到一定的积极作用。 展开更多
关键词 SEDline镇静监测 右美托咪定 胸腔镜 肺叶切除术
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钻爆法隧道主动支护体系力学机理及设计模型
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作者 王志龙 王明年 +3 位作者 张霄 于丽 童建军 刘大刚 《铁道学报》 北大核心 2026年第1期190-201,共12页
针对机械化全断面法隧道工程掌子面、进尺段及支护段稳定性控制难题,基于主动支护力学特征,展开对机械化全断面法施工隧道主动支护体系及设计模型的研究。基于隧道施工全过程围岩变形力学特征,参考隧道施工风险类型,构建以掌子面核心土... 针对机械化全断面法隧道工程掌子面、进尺段及支护段稳定性控制难题,基于主动支护力学特征,展开对机械化全断面法施工隧道主动支护体系及设计模型的研究。基于隧道施工全过程围岩变形力学特征,参考隧道施工风险类型,构建以掌子面核心土支护-超前预支护-锚固层支护-喷层支护为主要支护构件的隧道主动支护体系;基于主动支护构件作用特点建立对应的掌子面超前支护力学模型(M1)、锚固层支护力学模型(M2)和喷层支护力学模型(M3)。根据隧道施工失稳风险区域的差异性,提出3种隧道主动控制模式(模式A、模式B和模式C),并建立了基于掌子面稳定性系数的隧道主动控制模式确定方法。最终,基于主动支护力学模型,建立各主动控制模式下隧道主动支护体系的设计模型。 展开更多
关键词 机械化全断面法 主动支护体系 预应力锚杆 超前支护 早高强喷射混凝土 设计模型
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香鱼(Plecoglossus altivelis)CC型趋化因子受体3(CCR3)基因的分子鉴定及其对鳗弧菌感染响应的研究 被引量:1
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作者 张玲玲 余莉 +2 位作者 李长红 苗亮 陈炯 《海洋与湖沼》 CAS CSCD 北大核心 2021年第6期1456-1464,共9页
CC趋化因子受体3(CCR3)是CC型趋化因子的受体,属于G蛋白耦联受体(GPCRs)家族成员,与过敏等多种炎性疾病密切相关。为探讨香鱼CCR3(PaCCR3)在响应鳗弧菌感染时的表达变化,从转录组测序数据中获得了PaCCR3基因全长cDNA序列。序列分析表明,... CC趋化因子受体3(CCR3)是CC型趋化因子的受体,属于G蛋白耦联受体(GPCRs)家族成员,与过敏等多种炎性疾病密切相关。为探讨香鱼CCR3(PaCCR3)在响应鳗弧菌感染时的表达变化,从转录组测序数据中获得了PaCCR3基因全长cDNA序列。序列分析表明,PaCCR3具有7次跨膜结构,与胡瓜鱼CCR3氨基酸序列同源性最高(84.6%)。系统进化树分析表明,哺乳类、两栖类和鱼类CCR3单独成簇,鱼类CCR3形成一个大簇;PaCCR3与胡瓜鱼CCR3进化相关性最高。实时荧光定量PCR结果显示,PaCCR3基因mRNA在单核/巨噬细胞(MO/MФ)中表达量最高;鳗弧菌感染后肝、脾和头肾中PaCCR3基因mRNA表达量显著上调;且香鱼MO/MФ经鳗弧菌体外刺激后,PaCCR3基因mRNA的表达量显著上调。Western blot分析表明经鳗弧菌体外刺激后,香鱼MO/MФ中PaCCR3蛋白的表达量也显著增加。综上,PaCCR3基因mRNA及其编码蛋白响应于病原体感染而被诱导表达。研究结果首次揭示了香鱼CCR3基因mRNA及蛋白的表达响应于鳗弧菌侵染,它可能通过介导MO/MФ的功能活性参与免疫应答,可为深入探究鱼类CCR3的功能及作用机制提供新的切入点。 展开更多
关键词 香鱼(Plecoglossus altivelis) CCR3 单核/巨噬细胞 鳗弧菌 表达分析
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787~952nm可调谐全固态Cr:LiSAF激光器 被引量:1
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作者 栾昆鹏 于力 +3 位作者 沈炎龙 陶蒙蒙 马连英 易爱平 《现代应用物理》 2016年第2期29-32,共4页
实现了X型腔全固态端面泵浦Cr:LiSAF激光器的高效率输出和宽谱调谐。斜效率最高为33.3%,在吸收泵浦功率为650mW时,输出功率最高达160mW。在谐振腔内插入双折射滤光片(BF)调谐,调谐范围达787.952nm。测量了激光器的光谱、光束质量等... 实现了X型腔全固态端面泵浦Cr:LiSAF激光器的高效率输出和宽谱调谐。斜效率最高为33.3%,在吸收泵浦功率为650mW时,输出功率最高达160mW。在谐振腔内插入双折射滤光片(BF)调谐,调谐范围达787.952nm。测量了激光器的光谱、光束质量等,分析了激光器效率和调谐范围的限制因素。研究表明,X型腔全固态端面泵浦的Cr:LiSAF激光器可以实现高效的近红外宽谱调谐输出。 展开更多
关键词 固体激光器 近红外 调谐激光器 Cr:LiSAF激光
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