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HDGF derived from Müller cells enhances the activation of microglia in diabetic retinopathy
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作者 Aowang Qiu Wenjie Yin +3 位作者 Ningyu Wang Xin Wang Qinghuai Liu weiwei zhang 《Journal of Biomedical Research》 2026年第1期63-75,共13页
Diabetic retinopathy(DR),a common complication of diabetes,is characterized by retinal angiogenesis and inflammation.The role of hepatoma-derived growth factor(HDGF)in mediating inflammation during DR remains unclear.... Diabetic retinopathy(DR),a common complication of diabetes,is characterized by retinal angiogenesis and inflammation.The role of hepatoma-derived growth factor(HDGF)in mediating inflammation during DR remains unclear.We measured HDGF levels in the aqueous humor and found that HDGF was increased in DR but decreased after anti-angiogenesis treatment.Using public single-cell RNA sequencing datasets,we found that elevated HDGF in DR was mainly produced by Müller cells and targeted microglia.Additionally,integrin beta 2(Itgb2),a target gene of HDGF that induces microglial activation,was significantly upregulated in DR.To verify these results,we performed enzyme-linked immunosorbent assays,quantitative reverse transcription-PCR,Western blotting,and fluorescence immunostaining in cultured Müller and microglial cells treated with HDGF or anti-HDGF,as well as in DR mice receiving intravitreal injections of HDGF or its antibody.Exogenous HDGF further promoted microglial activation,migration,and secretion of pro-inflammatory cytokines,while neutralization of HDGF suppressed these effects caused by high glucose.Furthermore,the HDGF receptor nucleolin was overexpressed in microglia under high glucose stimulation.Therefore,blocking HDGF from Müller cells in DR reduced the excessive inflammatory response in microglia,highlighting HDGF as a potential therapeutic target. 展开更多
关键词 hepatoma-derived growth factor diabetic retinopathy MICROGLIA Müller cell inflammatory response integrin beta 2
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“学、教、践”三位一体理念下现代分析测试技术本科生培养现状与质量提高措施 被引量:1
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作者 张维维 任永鑫 +1 位作者 张红 鹿可 《大学化学》 2025年第10期78-85,共8页
本文立足课堂教学,针对本科生“现代分析测试技术”课程设计,分析了学生学习动力不足和教师教学方法陈旧等问题。以“学、教、践”三位一体理念为指导,提出拓宽网络平台、提高教师素养、开放实验室等措施,切实提高人才培养质量和学生实... 本文立足课堂教学,针对本科生“现代分析测试技术”课程设计,分析了学生学习动力不足和教师教学方法陈旧等问题。以“学、教、践”三位一体理念为指导,提出拓宽网络平台、提高教师素养、开放实验室等措施,切实提高人才培养质量和学生实践能力。 展开更多
关键词 本科生教育 现代分析测试技术 三位一体 课程设计 教学改革
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Energy transfer enhanced photocatalytic hydrogen evolution in organic heterostructure nanoparticles via flash nanoprecipitation processing 被引量:1
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作者 Miaojie Yu weiwei zhang +4 位作者 Xueyan Liu Guohui Zhao Jun Du Yongzhen Wu Wei-Hong Zhu 《Green Energy & Environment》 2025年第2期390-398,共9页
Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a b... Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a binary nanophotocatalyst fabricated by blending two polymers,PS-PEG5(PS)and PBT-PEG5(PBT),with matched absorption and emission spectra,enabling a Forster resonance energy transfer(FRET)process for enhanced photocatalysis.These heterostructure nanophotocatalysts are processed using a facile and scalable flash nanoprecipitation(FNP)technique with precious kinetic control over binary nanoparticle formation.The resulting nanoparticles exhibit an exceptional photocatalytic hydrogen evolution rate up to 65 mmol g^(-1) h^(-1),2.5 times higher than that single component nanoparticles.Characterizations through fluorescence spectra and transient absorption spectra confirm the hetero-energy transfer within the binary nanoparticles,which prolongs the excited-state lifetime and extends the namely“effective exciton diffusion length”.Our finding opens new avenues for designing efficient organic photocatalysts by improving exciton migration. 展开更多
关键词 Polymer photocatalysts NANOPARTICLES Hydrogen evolution Forster resonance energy transfer
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微波高温固相接枝制备极性无规共聚聚丙烯树脂及应用
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作者 张微微 潘明 +1 位作者 姚远 王崧合 《高分子材料科学与工程》 北大核心 2025年第5期140-148,共9页
以无规共聚聚丙烯(M26ET)为原料,通过微波高温固相接枝技术,在无引发剂、无溶剂的情况下将马来酸酐(MAH)接枝到聚丙烯分子链上,实现了无规共聚聚丙烯的极性改性,进一步碱洗,制备了一种全新的无规共聚聚丙烯接枝盐树脂。红外表征和熔融... 以无规共聚聚丙烯(M26ET)为原料,通过微波高温固相接枝技术,在无引发剂、无溶剂的情况下将马来酸酐(MAH)接枝到聚丙烯分子链上,实现了无规共聚聚丙烯的极性改性,进一步碱洗,制备了一种全新的无规共聚聚丙烯接枝盐树脂。红外表征和熔融指数测试均证明了马来酸酐的成功接枝,并通过酸碱滴定法测定了接枝率。经过流变性能测试,发现在接枝过程中聚丙烯分子产生了长支链,熔体强度增加。差示扫描量热法和X射线衍射分析表明,接枝的马来酸(MA)及马来酸钠(NaMA)基团有利于聚丙烯结晶,并产生了具有增韧作用的β晶型。将制备的极性树脂作为相容剂用于聚丙烯/聚烯烃弹性体(POE)/滑石粉(TALC)复合材料体系,发现较高接枝率的马来酸钠接枝聚丙烯(PP-g-NaMA)可以同时提高复合材料的刚性、韧性和耐热性,效果甚至优于接枝率大于其2倍的商业化极性树脂。 展开更多
关键词 无规共聚聚丙烯 微波 固相接枝 相容剂
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Fast Evaluation Peanut Oil Quality by Synchronous Fluorescence Spectroscopy and Statistical Analysis 被引量:1
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作者 weiwei zhang Riqin Lv +1 位作者 Yanhui Sun Haiyang Gu 《Agricultural Sciences》 2021年第5期565-574,共10页
<div style="text-align:justify;"> Peanut oil oxidation was to monitor and quantify combining synchronous fluorescence spectroscopy and chemometrics. Peanut oil was subjected to an accelerated oxidation... <div style="text-align:justify;"> Peanut oil oxidation was to monitor and quantify combining synchronous fluorescence spectroscopy and chemometrics. Peanut oil was subjected to an accelerated oxidation testing. The spectral and related chemical indicators were caught during oxidation induce testing. Fluorescence spectra were gained for each sample with simultaneous excitation from 200 to 800 nm and the offsets (Δλ) of 10 to 180 nm during the oxidation process. The results showed the induce period (IP) of the peanut oil was 16.45 h. Parallel factor analysis (PARAFAC) was performed to select the best Δλ interval of 70 nm, which spectral data was the most suitable for interval partial least square (iPLS) and synergy interval PLS (siPLS) modeling and forecast. The study presented all interval selection methods had the better results than the global spectrum modelling. iPLS reached the best into 10 intervals with a ratio of prediction to deviation (RPD) of 2.10. siPLS that separated the whole spectrum into 15 intervals and combined the third intervals (282 to 320 nm, 362 to 400 nm, and 761 to 800 nm) had a ratio of RPD of 2.26. The results showed the optimal siPLS model performed a little better than iPLS. The established model lying on interval selection could improve the prediction accuracy. It could provide a quick, accurate method to monitor oil oxidation process. </div> 展开更多
关键词 Synchronous Fluorescence Spectroscopy Peanut Oil Oxidation Stability CHEMOMETRICS
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Envisioning the blueprint:Aeronautics in large models era
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作者 weiwei zhang Shule ZHAO 《Chinese Journal of Aeronautics》 2025年第8期139-141,共3页
Following the groundbreaking introduction of the Transformer architecture in 2017,the development of Large Language Models(LLMs)formally commenced.In May 2020,Chat GPT-3,with over one hundred billion parameters,entere... Following the groundbreaking introduction of the Transformer architecture in 2017,the development of Large Language Models(LLMs)formally commenced.In May 2020,Chat GPT-3,with over one hundred billion parameters,entered the public eye,marking a significant milestone in LLM advancement. 展开更多
关键词 AERONAUTICS large languagemodels transformer architecture transformerarchitecture llms chatgpt large language models llms formally
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Decision-making and confrontation in close-range air combat based on reinforcement learning
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作者 Mengchao YANG Shengzhe SHAN weiwei zhang 《Chinese Journal of Aeronautics》 2025年第9期401-420,共20页
The high maneuverability of modern fighters in close air combat imposes significant cognitive demands on pilots,making rapid,accurate decision-making challenging.While reinforcement learning(RL)has shown promise in th... The high maneuverability of modern fighters in close air combat imposes significant cognitive demands on pilots,making rapid,accurate decision-making challenging.While reinforcement learning(RL)has shown promise in this domain,the existing methods often lack strategic depth and generalization in complex,high-dimensional environments.To address these limitations,this paper proposes an optimized self-play method enhanced by advancements in fighter modeling,neural network design,and algorithmic frameworks.This study employs a six-degree-of-freedom(6-DOF)F-16 fighter model based on open-source aerodynamic data,featuring airborne equipment and a realistic visual simulation platform,unlike traditional 3-DOF models.To capture temporal dynamics,Long Short-Term Memory(LSTM)layers are integrated into the neural network,complemented by delayed input stacking.The RL environment incorporates expert strategies,curiositydriven rewards,and curriculum learning to improve adaptability and strategic decision-making.Experimental results demonstrate that the proposed approach achieves a winning rate exceeding90%against classical single-agent methods.Additionally,through enhanced 3D visual platforms,we conducted human-agent confrontation experiments,where the agent attained an average winning rate of over 75%.The agent's maneuver trajectories closely align with human pilot strategies,showcasing its potential in decision-making and pilot training applications.This study highlights the effectiveness of integrating advanced modeling and self-play techniques in developing robust air combat decision-making systems. 展开更多
关键词 Air combat Decision making Flight simulation Reinforcement learning Self-play
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A light-responsive multilayered 3D porous Ga_(2)O_(3) hydrogel for photocatalytic antibacterial therapy promoting healing of MDR S.aureus-infected wounds
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作者 Yimei Wang Xuechao Shi +8 位作者 Shuxian Hou Lei zhang Xinxin Liu Guoqiang Yang Yuxuan Wang Muwei Hao weiwei zhang Jun Wang Fei Ge 《Journal of Materials Science & Technology》 2025年第22期188-202,共15页
The skin wound is susceptible to bacterial invasion,which hinders the healing of the wound,especially when infected with multi-drug resistant strains.This demands novel bioactive materials to combat bacterial infectio... The skin wound is susceptible to bacterial invasion,which hinders the healing of the wound,especially when infected with multi-drug resistant strains.This demands novel bioactive materials to combat bacterial infections.In this study,gallium oxide nanoparticles(Ga_(2)O_(3)NPs)were successfully synthesized through high-temperature thermal decomposition,exhibiting excellent biocompatibility and photocatalytic antimicrobial activity.The Ga_(2)O_(3)NPs were crosslinked into chitosan hydrogel to create a light-responsive multilayered 3D porous hydrogel(Ga_(2)O_(3)NPs hydrogel)for use in photocatalytic antimicrobial therapy(PCAT).The prepared Ga_(2)O_(3)NPs hydrogel exhibits broad-spectrum photocatalytic activity and remarkable antibacterial efficacy against E.coli and S.aureus.It effectively eradicates biofilms,promotes reactive oxygen species production,disrupts bacterial cell membranes,and induces nucleic acid leakage,ultimately resulting in bacterial death.Additionally,it exhibits excellent biosafety.Both in vitro pigskin and in vivo mouse wound infection models have confirmed the remarkable efficacy of Ga_(2)O_(3)NPs hydrogel in PCAT.Notably,Ga_(2)O_(3)NPs hydrogel created a moist environment for the wound in an MDR S.aureus-infected mouse wound model,demonstrating significant potential to facilitate wound healing and minimize scar formation.This study introduces a novel hydrogel dressing without antibiotic components for resistant bacterial-infected wounds. 展开更多
关键词 Light-responsive 3D porous structure Moist environment Photocatalysis Wound healing
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VW-PINNs:A volume weighting method for PDE residuals in physics-informed neural networks
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作者 Jiahao Song Wenbo Cao +1 位作者 Fei Liao weiwei zhang 《Acta Mechanica Sinica》 2025年第3期65-79,共15页
Physics-informed neural networks(PINNs)have shown remarkable prospects in solving the forward and inverse problems involving partial differential equations(PDEs).The method embeds PDEs into the neural network by calcu... Physics-informed neural networks(PINNs)have shown remarkable prospects in solving the forward and inverse problems involving partial differential equations(PDEs).The method embeds PDEs into the neural network by calculating the PDE loss at a set of collocation points,providing advantages such as meshfree and more convenient adaptive sampling.However,when solving PDEs using nonuniform collocation points,PINNs still face challenge regarding inefficient convergence of PDE residuals or even failure.In this work,we first analyze the ill-conditioning of the PDE loss in PINNs under nonuniform collocation points.To address the issue,we define volume weighting residual and propose volume weighting physics-informed neural networks(VW-PINNs).Through weighting the PDE residuals by the volume that the collocation points occupy within the computational domain,we embed explicitly the distribution characteristics of collocation points in the loss evaluation.The fast and sufficient convergence of the PDE residuals for the problems involving nonuniform collocation points is guaranteed.Considering the meshfree characteristics of VW-PINNs,we also develop a volume approximation algorithm based on kernel density estimation to calculate the volume of the collocation points.We validate the universality of VW-PINNs by solving the forward problems involving flow over a circular cylinder and flow over the NACA0012 airfoil under different inflow conditions,where conventional PINNs fail.By solving the Burgers’equation,we verify that VW-PINNs can enhance the efficiency of existing the adaptive sampling method in solving the forward problem by three times,and can reduce the relative L 2 error of conventional PINNs in solving the inverse problem by more than one order of magnitude. 展开更多
关键词 Physics-informed neural networks Partial differential equations Nonuniform sampling Residual balancing Deep learning
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Facile top-down fabrication of integrated amorphous NiFe-based electrocatalytic electrodes for high current and long-life oxygen evolution
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作者 weiwei zhang Qingyun lv +5 位作者 Long Hou Jiantao Wang Zhipeng Long Xionggang Lu Xing Yu Xi Li 《Journal of Materials Science & Technology》 2025年第8期11-21,共11页
Developing an industrially relevant electrode with high catalytic activity,stability,and tunable composition/size for large-scale water electrolysis is a significant challenge.We have created an integrated elec-trode(... Developing an industrially relevant electrode with high catalytic activity,stability,and tunable composition/size for large-scale water electrolysis is a significant challenge.We have created an integrated elec-trode(NFM30-N)for the oxygen evolution reaction(OER)using a facile top-down approach that combines arc melting with dealloying-oxidation.Due to the dealloying-oxidation effect,the asderived porous amorphous M-O,M-OH,and M-OOH(M=Ni,Fe)nanocones cover the basic NiFeMn alloy.This integrated design enables NFM30-N to exhibit outstanding OER performance at high current densities,requiring low overpotentials of only 282 and 323 mV to achieve large current densities of 100 and 500 mA cm^(-2),respectively.It also displays a small Tafel slope of 44.1 mV dec^(-1) and remarkable stability for over 100 h at 100 and 500 mA cm^(-2).When used as an anode,a two-electrode electrolyzer cell with NFM30-N at 500 mA cm^(-2) only requires a cell voltage of 1.619 V and exhibits excellent stability,with almost no performance degradation after continuous chronopotentiometry test for each 100 h at 500 and 100 mA cm^(-2).This exceptional OER electrocatalytic performance is attributed to the integrated structure providing high electrical conductivity and stability,the presence of numerous active sites due to dealloying and the amorphous structure,and the promotion of the OER process by M-O,M-OH,and M-OOH species.This work offers a novel idea for fabricating integrated,industrially relevant electrocatalytic electrodes through traditional metallurgy combined with dealloying-oxidation. 展开更多
关键词 Arc melting Dealloying-oxidation Integration Amorphous NiFe-based electrocatalytic electrode Industrial-scale oxygen evolution reaction(OER)
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Ship emissions and reduction potential under domestic policies and international cooperation:A case study in Hainan,China
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作者 weiwei zhang Wen Yi +8 位作者 Tingkun He Xin Peng Qiao Xing Xiaochen Wu Zhaohui Yang Rongfu Xie Aidan Xian Huan Liu Jiming Hao 《Journal of Environmental Sciences》 2025年第10期253-266,共14页
Ship emissions contribute considerably to air pollution and are expected to decline under domestic policies and international cooperation such as green shipping corridors(GSCs).However,evaluation of the emission reduc... Ship emissions contribute considerably to air pollution and are expected to decline under domestic policies and international cooperation such as green shipping corridors(GSCs).However,evaluation of the emission reduction potential by the Domestic Emission Control Area(DECA)policy and GSC cooperation is still lacking.Here,a series of multi-year high spatiotemporal ship emission inventories around Hainan,a representative island province of China,were developed with the state-of-the-art Shipping Emission Inventory Model.The improved origin-destination identification algorithm allowed emission allocation to port level.The emission reduction potential of the DECA policy and Hainan's joining GSCwas analyzed.In 2022,ship emission intensity in waters 12 Nm from Hainan(Hainan-12Nm)were 6.4%-7.4% of that in waters 12 Nm from China.From 2019 to 2022,Hainan-12Nm emissions dropped by 66.7%-77.8% for SO_(2) and PM2.5.Ideally,with adequate ultra-low-sulfur fuel,DECA can reduce SO_(2) and PM2.5 emissions by 16.6% and 22.4% yearly compared with no-DECA scenario.However,emission reduction would drop markedly if ultra-low-sulfur fuel is short in supply.Emissions of voyages passing through 200 Nm from Hainan took up 1%-4%of international shipping emissions,implying great emission reduction potential for Hainan's establishing GSCs,especially considering the flourishing South-South trade.This study provides a thorough assessment of the current state of shipping emissions around Hainan as well as offers excellent data support for Hainan to further advance the future upgrade of ship emission management policies. 展开更多
关键词 Ship emission Air pollution Control strategy Domestic emission control area Green shipping corridor
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A novel paradigm for solving PDEs:multi-scale neural computing
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作者 Wei Suo weiwei zhang 《Acta Mechanica Sinica》 2025年第6期76-92,共17页
Numerical simulation is dominant in solving partial differential equations(PDEs),but balancing fine-grained grids with low computational costs is challenging.Recently,solving PDEs with neural networks(NNs)has gained i... Numerical simulation is dominant in solving partial differential equations(PDEs),but balancing fine-grained grids with low computational costs is challenging.Recently,solving PDEs with neural networks(NNs)has gained interest,yet cost-effectiveness and high accuracy remain a challenge.This work introduces a novel paradigm for solving PDEs,called multi-scale neural computing(MSNC),considering spectral bias of NNs and local approximation properties in the finite difference method(FDM).The MSNC decomposes the solution with a NN for efficient capture of global scale and the FDM for detailed description of local scale,aiming to balance costs and accuracy.Demonstrated advantages include higher accuracy(10 times for 1D PDEs,20 times for 2D PDEs)and lower costs(4 times for 1D PDEs,16 times for 2D PDEs)than the standard FDM.The MSNC also exhibits stable convergence and rigorous boundary condition satisfaction,showcasing the potential for hybrid of NN and numerical method. 展开更多
关键词 Neural computing Partial differential equations Hybrid strategy Numerical methods Neural networks
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Asymmetric ionomer configuration in membrane electrode assembly for enhanced water management and performance in anion exchange membrane fuel cells
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作者 Xiaocan Wang Tengyu He +5 位作者 Jiayuan Mao weiwei zhang Donghai Mei Xikang Zhao Aimei Zhu Qiugen zhang 《Journal of Energy Chemistry》 2025年第6期363-372,I0009,共11页
Anion exchange membrane fuel cells(AEMFCs)are considered a more affordable technology compared to proton exchange membrane fuel cells(PEMFCs),but the performance and durability of AEMFCs are still not competent with P... Anion exchange membrane fuel cells(AEMFCs)are considered a more affordable technology compared to proton exchange membrane fuel cells(PEMFCs),but the performance and durability of AEMFCs are still not competent with PEMFCs owing to the more challenging water management,which severely hinders its development and real-life applications.In this study,we introduce the strategy to boost the performance and stability of the membrane electrode assembly(MEA)of AEMFCs by regulating the hydrophilicity of the anode and cathode ionomers.Two poly(biphenyl alkylene)ionomers with different hydrophilicity are synthesized and used to fabricate MEAs with asymmetric or symmetric ionomer configurations in the anodic and cathodic catalyst layers(CLs)for AEMFCs.Molecular dynamics(MD)simulations have revealed different diffusion rates of water in the hydrophobic anode and the hydrophilic cathode,which show the potential of this design to improve water management in AEMFCs,The effectiveness of this design is also confirmed by experimental results that the MEA with this asymmetric configuration exhibits the highest power and current densities of 1.58 W cm^(-2)or 5.58 A cm^(-2),respectively,among all configurations.Furthermore,this configuration also enhances the durability,with the MEA showing a voltage decay rate of only 313.1μV h^(-1)after 500 h of in-situ durability test at 0.2 A cm^(-2).This study provides new insights into the rational design of more efficient water management in MEA for high-performance AEMFCs. 展开更多
关键词 Water management Asymmetric ionomer configuration Membrane electrode assembly Anion exchange membrane fuel cells
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Indole enhanced the bactericidal efficacy of tetracycline against pathogen Vibrio splendidus
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作者 Jinxia zhang Zhixin MU +1 位作者 Qiling ZHOU weiwei zhang 《Journal of Oceanology and Limnology》 2025年第5期1623-1635,共13页
Recently,more and more bacteria have been reported to become tolerant to antibiotics.In this study,one tnaA gene involved in indole production,and the effect of exogenous indole on the formation of persister cells spe... Recently,more and more bacteria have been reported to become tolerant to antibiotics.In this study,one tnaA gene involved in indole production,and the effect of exogenous indole on the formation of persister cells specific to tetracycline in Vibrio splendidus were characterized.The tnaA Vs gene was first cloned and conditionally expressed in Escherichia coli Rosetta(DE3).To investigate the regulatory effect of TnaA Vs,the tnaA deletion strain AJ01/ΔtnaA was constructed by in-frame deletion.The undetected extracellular indole in the AJ01/ΔtnaA indicated that TnaA was the solo enzyme to produce indole in V.splendidus.The drop plate method showed that AJ01/ΔtnaA was more tolerant to the higher concentration of tetracycline than that of AJ01,being 340-fold higher in the proportion of survived cells when cell density OD 600≈0.65.Moreover,the synergistic effects of indole and tetracycline on killing of V.splendidus were determined.Results show that addition of 2-mmol/L indole increased the susceptibility of both AJ01 and AJ01/ΔtnaA to 10×minimum inhibitory concentration tetracycline.To explore the genes and pathways regulated by TnaA Vs,the transcriptomic analysis between AJ01 and AJ01/ΔtnaA was performed.Result shows that TCA cycle,arginine biosynthesis,quorum sensing and microbial metabolism in diverse environments were downregulated,while the ribosome pathways,the protein metabolic process,peptide biosynthetic and metabolic process were upregulated in the AJ01/ΔtnaA.This study shows that indole could enhance the bactericidal effect of tetracycline on V.splendidus by decreased ribosome level probably but increased ATP level. 展开更多
关键词 Vibrio splendidus INDOLE persister cell transcriptomic analysis
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Application of molecular identification techniques in traditional Chinese medicine
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作者 Jiankun Jin weiwei zhang +5 位作者 Rui Liu Ruiqi Ma Yuzheng Xiang Yibo Wang Ying Li Yu Chen 《Asian Journal of Traditional Medicines》 2025年第4期173-180,共8页
In recent years,molecular identification technology has become the predominant approach for the identification of traditional Chinese medicine.The molecular identification techniques in recent years were analyzed and ... In recent years,molecular identification technology has become the predominant approach for the identification of traditional Chinese medicine.The molecular identification techniques in recent years were analyzed and summarized in this paper,such as RAPD,ISSR,RFLP,AFLP,SNP,and DNA bar code sequence analysis techniques.By consulting Sciencedirect databases and Web of Science databases,2348 related articles were found,of which 39 were related to molecular identification techniques and traditional Chinese medicine.The application of the molecular identification techniques in four aspects was reviewed,namely the identification on the authenticity(true or false),multi-source identification and genetic diversity,producing area,and growing year discrimination of traditional Chinese medicine. 展开更多
关键词 traditional Chinese medicine molecular identification techniques DNA bar code
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Upper-ocean cooling rate of the South China Sea in response to extreme cold surges and weak cold-air invasions
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作者 weiwei zhang Dongxiao Wang +3 位作者 Marco Y.-T.Leung Lin Wang Jinchi Xie Wen Zhou 《Atmospheric and Oceanic Science Letters》 2025年第3期20-26,共7页
Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature... Cold-surge events can lead to temperature drops and strong winds,which then leads to upper-ocean cooling and deepening of the mixed-layer depth,as illustrated in previous studies.In this study,based on the temperature drop of Shanwei meteorological station,two extreme cold surges and five weak cold invasions in the South China Sea are simulated using an ocean-atmosphere coupled model to investigate their different impacts on the upper-ocean temperature.The diffusion term contributes to the difference in temperature tendency of the upper 20 m,while the advection term contributes to the positive difference from 20 to 80 m of the offshore region and negative difference from 80 to 160 m.In addition,the significant differences are attributed primarily to the influence of the upper-ocean temperature gradient,which subsequently impacts the advection term and results in notable differences in temperature tendency at depths from 80 to 160 m. 展开更多
关键词 Cold surges Upper-ocean temperature tendency Air-sea coupled model
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Effects of Using Softwood Pellet Biochar Prepared at Different Temperatures with Grass Chippings on Retention of Heavy Metals in Contaminated Soils
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作者 Kyari Umar Dunoma Limin Ma +14 位作者 Xingquan Shu Haiyan Yu weiwei zhang Chengcheng Bu Yong-Sik Wang Jiahong Luo Guangyao Chen Jinpeng Yu Ru zhang Yuchen Han Haoyu Zeng Matthew S. Wisseh Amina Grema Mustafa Mohammad Auwal Saidu Mufidat Mamman Khan 《Open Journal of Polymer Chemistry》 2024年第3期146-166,共21页
Heavy metals have been viewed as hazardous environmental pollutants, and anthropogenic activities due to their high toxicity and persistent nature in the environment. Anthropogenic activities such as artisanal mining,... Heavy metals have been viewed as hazardous environmental pollutants, and anthropogenic activities due to their high toxicity and persistent nature in the environment. Anthropogenic activities such as artisanal mining, industrial activities, improper usage of fertilizers and pesticides, and indiscriminate open waste disposal bring about an increase in the presence of heavy metals in the environment. In the Keffi Metropolis, different elements lead to land contamination which debilitates soil quality, plant survival, human well-being, and the environment as a result of extensive dispersion or quantity of heavy metals in the soil and water. In recent years, biochar has emerged as a promising soil amendment for mitigating heavy metal pollution due to its unique physicochemical properties. This paper provides the effects of softwood pellet biochar on the retention of heavy metals in contaminated soils. A microcosm experiment was carried out to investigate the effects of biochar on the retention of heavy metals in contaminated soils. This research aimed to give an overview of the effects of softwood biochar at different temperatures (550˚C and 700˚C) on the retention of heavy metals and metalloids released from the soil during water inundation. The results show that the addition of organic matter (grass chippings) minimizes heavy metal mobilization. Also, biochar at high temperatures is more effective than those at low temperatures. The expected outcome of the research analysis includes providing insights into the role of biochar in retaining heavy metal contamination and further understanding the use of biochar as a sorbent for the management of contaminated soil. 展开更多
关键词 Softwood Biochar Heavy Metal Contaminated Soil Grass Chips Keffi Metropolis MICROCOSM
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政治地理、企业内部控制与所得税税负
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作者 姚圣 张薇薇 《会计论坛》 CSSCI 2018年第1期23-35,共13页
已有文献证明了政治关联对企业所得税税负的影响,但对政治地理的税负效应研究较少,且没有涉及政治地理对企业所得税税负复杂影响的研究。本文通过手工收集中央政治局委员的工作地与出生地信息,构建了政治地理变量,以2013-2015年沪深... 已有文献证明了政治关联对企业所得税税负的影响,但对政治地理的税负效应研究较少,且没有涉及政治地理对企业所得税税负复杂影响的研究。本文通过手工收集中央政治局委员的工作地与出生地信息,构建了政治地理变量,以2013-2015年沪深A股上市公司作为研究样本,检验了政治地理对企业所得税税负的影响,并深入研究内部控制质量对政治地理与企业所得税关系的调节作用。研究结果表明,政治地理的得分越高,公司的企业所得税税负越低,这种效应在国有控股企业中更为显著;内部控制质量会加强政治地理与企业所得税税负的负相关关系,内部控制质量越好,企业所得税税负就越低。 展开更多
关键词 政治地理 企业所得税 企业内部控制
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与45钢对摩材料干摩擦条件下的摩擦学性能 被引量:3
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作者 张金鹏 张玮炜 +3 位作者 齐瑾 王小静 朱丽慧 金健 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第2期115-123,共9页
为选择与45钢对摩的摩擦副材料以适应干摩擦苛刻工况,采用RTEC多功能摩擦试验机,对超高分子量聚乙烯(UHMWPE)、改性聚醚醚酮树脂(改性PEEK)、浸渍呋喃树脂碳石墨(M120K)和浸渍巴氏合金碳石墨(M120B)4种配副材料的摩擦学性能进行测试,并... 为选择与45钢对摩的摩擦副材料以适应干摩擦苛刻工况,采用RTEC多功能摩擦试验机,对超高分子量聚乙烯(UHMWPE)、改性聚醚醚酮树脂(改性PEEK)、浸渍呋喃树脂碳石墨(M120K)和浸渍巴氏合金碳石墨(M120B)4种配副材料的摩擦学性能进行测试,并利用扫描电子显微镜对磨损表面进行观察和分析,从微观角度揭示了4种材料的摩擦磨损机理。结果表明,随着载荷和转速的增加,平均摩擦系数大致呈现出M120B<UHMWPE<改性PEEK<M120K的规律,磨损率则大致呈现出M120B<改性PEEK<M120K<UHMWPE的规律。当载荷增大时,UHMWPE和M120K由磨粒磨损逐渐转变为粘着磨损;改性PEEK以粘着磨损为主并伴随轻微的磨粒磨损;M120B表现出磨粒磨损与粘着磨损共存的形式。当转速增大时,UHMWPE和M120B以磨粒磨损为主并伴随轻微的粘着磨损;改性PEEK和M120K以粘着磨损为主并伴随轻微的磨粒磨损。 展开更多
关键词 45钢对摩材料 干摩擦 摩擦系数 磨损机理
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基于微信公众号构建无机化学实验微课平台的研究与探索 被引量:20
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作者 张玮玮 弓爱君 邱丽娜 《大学化学》 CAS 2020年第3期94-98,共5页
微课是在信息化时代和新教学理念下提出的新型教学模式,针对无机化学实验教学的现状,利用微信公众号构建微课平台,辅助教师进行课堂教学,解决了无机化学实验教学中安全培训、学生预习、学时少及实验内容多、实验药品购买使用受限、不能... 微课是在信息化时代和新教学理念下提出的新型教学模式,针对无机化学实验教学的现状,利用微信公众号构建微课平台,辅助教师进行课堂教学,解决了无机化学实验教学中安全培训、学生预习、学时少及实验内容多、实验药品购买使用受限、不能做有毒实验等问题。通过微课教学还实现了实验内容多样化、演示操作可视化,从而提升学生学习的主观能动性,增强动手能力,规范实验操作流程,便于学生对实验重点难点的掌握,同时增强师生交流,满足各层次学生要求,提高课堂效率。 展开更多
关键词 无机化学实验 微课 微信公众号
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