期刊文献+
共找到1,208篇文章
< 1 2 61 >
每页显示 20 50 100
Influence of Series Choke on Damping of Switching Transients in Distribution Transformers 被引量:3
1
作者 Marek Florkowski Marek Fulczyk +3 位作者 Wojcicch Piasecki Magdalena Ostrogorksa Pawet Klyrs Jakub Furgat 《高电压技术》 EI CAS CSCD 北大核心 2013年第10期2492-2499,共8页
Distribution transformers operating in modern system grids or in industrial networks are subjected to many switching transients,which may occur due to routine operations,network reconfigurations or as reaction on prot... Distribution transformers operating in modern system grids or in industrial networks are subjected to many switching transients,which may occur due to routine operations,network reconfigurations or as reaction on protection signals.Depending on the network configuration and parameters,such events may lead to external overvoltages and result in additional stresses on the insulation system.This paper presents the influence of a series choke on damping of switching transients in distribution transformers.The impact of the choke is assessed by both amplitude and rise time reduction.The suppression of the transient rise time is shown for a test configuration involving distribution transformers connected to low loss cable lines and a medium voltage breaker.Such phenomena are especially typical for industrial networks where switching operations are very frequent.Both simulation and experiment results are given.Simulation results as well as measurement results confirmed that switching events can lead to high dU/dt and in consequence,can have adverse impacts on insulation system.Voltage escalation during switching event is strongly related with system conditions.The results obtained for presented mitigation method are promising and indicate significant dU/dt reduction as well as number of ignitions and voltage peak value.The protection of distribution transformers with a series choke is a new approach dedicated to environments prone to the occurrence of transients with high steepness.Experimental results show that the application of serial choke with suitable parameters realizes the reduction of dU/dt at the machines terminal from 24 kV/μs to 5 kV/μs,as well as the reduction of voltage peak value from 10 kV to 5 kV.The number of ignitions is also reduced. 展开更多
关键词 配电变压器 扼流圈 瞬变 开关 阻尼 切换操作 网络经营 绝缘系统
原文传递
State of the Art and Future Trends of Unconventional PD-Measurement at Power Transformers 被引量:1
2
作者 Jurgen Fabian Martin Neuwersch +2 位作者 Christof Sumereder Michael Muhr Robert Schwarz 《Journal of Energy and Power Engineering》 2014年第6期1093-1098,共6页
This paper discusses the current state of the art of diagnostics at power transformers. A special focus is set on the UHF-PD-measurement (ultra-high-frequency partial discharge measurement) because at power transfor... This paper discusses the current state of the art of diagnostics at power transformers. A special focus is set on the UHF-PD-measurement (ultra-high-frequency partial discharge measurement) because at power transformers, this diagnostic method has become more important in recent years. The current state, basics and principles of operations, proceedings as well as advantages of PD-measurement methods are covered. Furthermore problems and proposed solutions are discussed. Bushings and tap changers are not discussed in detail. In many cases, one single diagnostic method does not have the ability to sufficiently evaluate a power transformer. Therefore, a variety of diagnostic methods came up over times, which are commonly used by now. To expand the evaluation opportunities of power transformers, science strives to develop new diagnostic methods as well as to improve the existing ones. Furthermore, environmentally friendly and hardly inflammable ester liquids are examined for the use at power transformers and PD-measurement at HVDC (high voltage direct current) converter transformers as well. Potential diagnostic options and respectively current developments and findings in the field of oil-paper-insulation systems are outlined conclusively. 展开更多
关键词 Power transformer unconventional PD-measurement UHF-PD-measurement environmentally friendly alternativeinsulating liquids HVDC converter transformer.
在线阅读 下载PDF
Inherent potential of mitochondria-targeted interventions for chronic neurodegenerative diseases 被引量:2
3
作者 Min Zhou Min Zheng +8 位作者 Siyao Liang Maomao Li Jiarui Ma Shiyu Zhang Xinyao Song Yonglin Hu Yuhong Lyu Xingkun Ou Changwu Yue 《Neural Regeneration Research》 2026年第4期1409-1427,共19页
The cure rate for chronic neurodegenerative diseases remains low,creating an urgent need for improved intervention methods.Recent studies have shown that enhancing mitochondrial function can mitigate the effects of th... The cure rate for chronic neurodegenerative diseases remains low,creating an urgent need for improved intervention methods.Recent studies have shown that enhancing mitochondrial function can mitigate the effects of these diseases.This paper comprehensively reviews the relationship between mitochondrial dysfunction and chronic neurodegenerative diseases,aiming to uncover the potential use of targeted mitochondrial interventions as viable therapeutic options.We detail five targeted mitochondrial intervention strategies for chronic neurodegenerative diseases that act by promoting mitophagy,inhibiting mitochondrial fission,enhancing mitochondrial biogenesis,applying mitochondria-targeting antioxidants,and transplanting mitochondria.Each method has unique advantages and potential limitations,making them suitable for various therapeutic situations.Therapies that promote mitophagy or inhibit mitochondrial fission could be particularly effective in slowing disease progression,especially in the early stages.In contrast,those that enhance mitochondrial biogenesis and apply mitochondria-targeting antioxidants may offer great benefits during the middle stages of the disease by improving cellular antioxidant capacity and energy metabolism.Mitochondrial transplantation,while still experimental,holds great promise for restoring the function of damaged cells.Future research should focus on exploring the mechanisms and effects of these intervention strategies,particularly regarding their safety and efficacy in clinical settings.Additionally,the development of innovative mitochondria-targeting approaches,such as gene editing and nanotechnology,may provide new solutions for treating chronic neurodegenerative diseases.Implementing combined therapeutic strategies that integrate multiple intervention methods could also enhance treatment outcomes. 展开更多
关键词 Alzheimer's disease amyotrophic lateral sclerosis calcium homeostasis oxidative stress Huntington's disease mitochondrial dysfunction MITOCHONDRIA MITOPHAGY neurodegenerative diseases Parkinson's disease targeted therapy
暂未订购
Intervention effect and mechanism of Compound Herba Gueldenstaedtiae in a mouse model of breast hyperplasia
4
作者 Wu Yilin Tian Hongying +8 位作者 Sun Jiale Jiao Jiajia Zhao Zihan Shao Jinhuan Zhao Kaiyue Zhou Min Li Qian Li Zexin Yue Changwu 《中国组织工程研究》 北大核心 2026年第17期4377-4389,共13页
BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probi... BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia. 展开更多
关键词 Herba Gueldenstaedtiae traditional Chinese medicine compound mice with breast hyperplasia microbial fermentation gut microbiota network pharmacology short-chain fatty acids hormone levels inflammatory response endocrine disorders
暂未订购
Vortex-Induced Vibration Characteristics of an Underwater Manipulator in Pulsating Flow
5
作者 Yongqi Li Xia Liu +3 位作者 Zongqiang Li Derong Duan Senliang Dai Hui Zhang 《哈尔滨工程大学学报(英文版)》 2026年第1期63-81,共19页
Vortex-induced vibration(VIV)of an underwater manipulator in pulsating flow presents a notable engineering problem in precise control due to the velocity variation in the flow.This study investigates the VIV response ... Vortex-induced vibration(VIV)of an underwater manipulator in pulsating flow presents a notable engineering problem in precise control due to the velocity variation in the flow.This study investigates the VIV response of an underwater manipulator subjected to pulsating flow,focusing on how different postures affect the behavior of the system.The effects of pulsating parameters and manipulator arrangement on the hydrodynamic coefficient,vibration response,motion trajectory,and vortex shedding behaviors were analyzed.Results indicated that the cross flow vibration displacement in pulsating flow increased by 32.14%compared to uniform flow,inducing a shift in the motion trajectory from a crescent shape to a sideward vase shape.In the absence of interference between the upper and lower arms,the lift coefficient of the manipulator substantially increased with rising pulsating frequency,reaching a maximum increment of 67.0%.This increase in the lift coefficient led to a 67.05%rise in the vibration frequency of the manipulator in the in-line direction.As the pulsating amplitude increased,the drag coefficient of the underwater manipulator rose by 36.79%,but the vibration frequency in the cross-flow direction decreased by 56.26%.Additionally,when the upper and lower arms remained in a state of mutual interference,the cross-flow vibration amplitudes of the upper and lower arms were approximately 1.84 and 4.82 times higher in a circular-elliptical arrangement compared to an elliptical-circular arrangement,respectively.Consequently,the flow field shifted from a P+S pattern to a disordered pattern,disrupting the regularity of the motion trajectory. 展开更多
关键词 Underwater manipulator Pulsating flow Vortex-induced vibration TRAJECTORY Overlapping mesh method
在线阅读 下载PDF
Blood-brain barrier disruption and neuroinflammation in the hippocampus of a cardiac arrest porcine model:Single-cell RNA sequencing analysis 被引量:1
6
作者 Tangxing Jiang Yaning Li +11 位作者 Hehui Liu Yijun Sun Huidan Zhang Qirui Zhang Shuyao Tang Xu Niu Han Du Yinxia Yu Hongwei Yue Yunyun Guo Yuguo Chen Feng Xu 《Neural Regeneration Research》 2026年第2期742-755,共14页
Global brain ischemia and neurological deficit are consequences of cardiac arrest that lead to high mortality.Despite advancements in resuscitation science,our limited understanding of the cellular and molecular mecha... Global brain ischemia and neurological deficit are consequences of cardiac arrest that lead to high mortality.Despite advancements in resuscitation science,our limited understanding of the cellular and molecular mechanisms underlying post-cardiac arrest brain injury have hindered the development of effective neuroprotective strategies.Previous studies primarily focused on neuronal death,potentially overlooking the contributions of non-neuronal cells and intercellular communication to the pathophysiology of cardiac arrest-induced brain injury.To address these gaps,we hypothesized that single-cell transcriptomic analysis could uncover previously unidentified cellular subpopulations,altered cell communication networks,and novel molecular mechanisms involved in post-cardiac arrest brain injury.In this study,we performed a single-cell transcriptomic analysis of the hippocampus from pigs with ventricular fibrillation-induced cardiac arrest at 6 and 24 hours following the return of spontaneous circulation,and from sham control pigs.Sequencing results revealed changes in the proportions of different cell types,suggesting post-arrest disruption in the blood-brain barrier and infiltration of neutrophils.These results were validated through western blotting,quantitative reverse transcription-polymerase chain reaction,and immunofluorescence staining.We also identified and validated a unique subcluster of activated microglia with high expression of S100A8,which increased over time following cardiac arrest.This subcluster simultaneously exhibited significant M1/M2 polarization and expressed key functional genes related to chemokines and interleukins.Additionally,we revealed the post-cardiac arrest dysfunction of oligodendrocytes and the differentiation of oligodendrocyte precursor cells into oligodendrocytes.Cell communication analysis identified enhanced post-cardiac arrest communication between neutrophils and microglia that was mediated by neutrophil-derived resistin,driving pro-inflammatory microglial polarization.Our findings provide a comprehensive single-cell map of the post-cardiac arrest hippocampus,offering potential novel targets for neuroprotection and repair following cardiac arrest. 展开更多
关键词 Blood-brain barrier disruption cardiac arrest HIPPOCAMPUS microglia NEUROINFLAMMATION neuroprotection NEUTROPHIL oligodendrocyte dysfunction S100A8 single-cell RNA sequencing
暂未订购
Ultrahigh Dielectric Permittivity of a Micron-Sized Hf_(0.5)Zr_(0.5)O_(2) Thin-Film Capacitor After Missing of a Mixed Tetragonal Phase
7
作者 Wen Di Zhang Bing Li +3 位作者 Wei Wei Wang Xing Ya Wang Yan Cheng An Quan Jiang 《Nano-Micro Letters》 2026年第1期144-153,共10页
Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received wides... Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received widespread applications in high-storage-density dynamic random access memory and energy-efficient complementary metal-oxide-semiconductor devices.During bipolar high electric-field cycling in numbers close to dielectric breakdown,the dielectric permittivity suddenly increases by 30 times after oxygen-vacancy ordering and ferroelectric-to-nonferroelectric phase transition of near-edge plasma-treated Hf_(0.5)Zr_(0.5)O_(2) thin-film capacitors.Here we report a much higher dielectric permittivity of 1466 during downscaling of the capacitor into the diameter of 3.85μm when the ferroelectricity suddenly disappears without high-field cycling.The stored charge density is as high as 183μC cm^(−2) at an operating voltage/time of 1.2 V/50 ns at cycle numbers of more than 10^(12) without inducing dielectric breakdown.The study of synchrotron X-ray micro-diffraction patterns show missing of a mixed tetragonal phase.The image of electron energy loss spectroscopy shows the preferred oxygen-vacancy accumulation at the regions near top/bottom electrodes as well as grain boundaries.The ultrahigh dielectric-permittivity material enables high-density integration of extremely scaled logic and memory devices in the future. 展开更多
关键词 Hf_(0.5)Zr_(0.5)O_(2)thin film Ultrahigh dielectric permittivity Near-edge plasma treatment Oxygen vacancy Charge storage
在线阅读 下载PDF
Porcine decellularized nerve matrix hydrogel attenuates neuroinflammation after peripheral nerve injury by inhibiting the TLR4/MyD88/NF-κB axis
8
作者 Rui Li Jianquan Liu +7 位作者 Liuxun Li Guotian Luo Xinrong Yuan Shichao Shen Yongpeng Shi Jianlong Wu Bin Yan Lei Yang 《Neural Regeneration Research》 2026年第3期1222-1235,共14页
Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological prop... Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury. 展开更多
关键词 anti-inflammatory reaction macrophage polarization NEUROINFLAMMATION peripheral nerve injury porcine decellularized nerve matrix hydrogel
暂未订购
Sox2-overexpressing neural stem cells alleviate ventricular enlargement and neurological dysfunction in posthemorrhagic hydrocephalus
9
作者 Baocheng Gao Haoxiang Wang +6 位作者 Shuang Hu Kunhong Zhong Xiaoyin Liu Ziang Deng Yuanyou Li Aiping Tong Liangxue Zhou 《Neural Regeneration Research》 2026年第2期769-779,共11页
Neural stem cells(NSCs)have the potential for self-renewal and multidirectional differentiation,and their transplantation has achieved good efficacy in a variety of diseases.However,only 1%-10%of transplanted NSCs sur... Neural stem cells(NSCs)have the potential for self-renewal and multidirectional differentiation,and their transplantation has achieved good efficacy in a variety of diseases.However,only 1%-10%of transplanted NSCs survive in the ischemic and hypoxic microenvironment of posthemorrhagic hydrocephalus.^(Sox2)is an important factor for NSCs to maintain proliferation.Therefore,^(Sox2)-overexpressing NSCs(NSC^(Sox2))may be more successful in improving neurological dysfunction after posthemorrhagic hydrocephalus.In this study,human NSC^(Sox2)was transplanted into a posthemorrhagic hydrocephalus mouse model,and retinoic acid was administered to further promote NSC differentiation.The results showed that NSC^(Sox2)attenuated the ventricular enlargement caused by posthemorrhagic hydrocephalus and improved neurological function.NSC^(Sox2)also promoted nerve regeneration,inhibited neuroinflammation and promoted M2 polarization(anti-inflammatory phenotype),thereby reducing cerebrospinal fluid secretion in choroid plexus.These findings suggest that NSC^(Sox2)rescued ventricular enlargement and neurological dysfunction induced by posthemorrhagic hydrocephalus through neural regeneration and modulation of inflammation. 展开更多
关键词 ANGIOGENESIS cerebrospinal fluid hippocampal transplantation inflammation MICROGLIA neural stem cells NEUROGENESIS posthemorrhagic hydrocephalus retinoic acid ^(Sox2)
暂未订购
Design optimisation for distance between additional and tap winding in high-voltage transformers 被引量:3
10
作者 Kamran Dawood Ahmet Kerem Köseoğlu Güven Kömürgöz 《High Voltage》 SCIE EI 2020年第6期716-723,共8页
The transformer is one of the main components in the power network and transformer windings are one of the most expensive elements in the power transformer. Optimisation of winding distances is one of the most importa... The transformer is one of the main components in the power network and transformer windings are one of the most expensive elements in the power transformer. Optimisation of winding distances is one of the most important parameters during the manufacturing of transformer. The distance between the windings in the two winding transformers is well known to transformer designers and manufacturers. However, insulation of the high voltage transformer with additional winding and tap winding is still a major problem for transformer designers. In this study, the additional winding to tap winding distance optimisation is made for a high voltage power transformer. Optimisation of the transformer's windings just not minimises the cost of the transformer but also increases the lifetime of the transformer. With additional winding and tap winding in high-voltage transformers, insulation distance is a major concern for minimising the cost and size of the high voltage transformer. In this study, an approach is made to balance the cost, size, and safety of high voltage transformers. The optimised distance and position between tap winding and additional winding are determined by using the finite element analysis. The finite element method results were also verified by making a prototype transformer. 展开更多
关键词 WINDING INSULATION HIGH
在线阅读 下载PDF
Optimization of Mg-based hydrogen storage materials with multicomponent and high-entropy catalysts 被引量:1
11
作者 Yu Sun Jiayi Cheng +2 位作者 Yaru Jiang Yafei Liu Yijing Wang 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2699-2712,共14页
Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated therma... Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated thermal conditions,sluggish dehydrogena-tion kinetics,and high thermodynamic stability,limit its practical application.One effective method of addressing these challenges is cata-lyst doping,which effectively boosts the hydrogen storage capability of Mg-based materials.Herein,we review recent advancements in catalyst-doped MgH_(2) composites,with particular focus on multicomponent and high-entropy catalysts.Structure-property relationships and catalytic mechanisms in these doping strategies are also summarized.Finally,based on existing challenges,we discuss future research directions for the development of Mg-based hydrogen storage systems. 展开更多
关键词 magnesium hydride multicomponent materials high-entropy materials hydrogen storage catalyst doping kinetics
在线阅读 下载PDF
Zhongfeng Xingnao Liquid ameliorates post-stroke cognitive impairment through sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway 被引量:1
12
作者 Wenqin Yang Wen Wen +4 位作者 Hao Chen Haijun Zhang Yun Lu Ping Wang Shijun Xu 《Chinese Journal of Natural Medicines》 2025年第1期77-89,共13页
The activation of the sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing ... The activation of the sirtuin1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase 1(HO-1)pathway has been shown to mitigate oxidative stress-induced apoptosis and mitochondrial damage by reducing reactive oxygen species(ROS)levels.Clinical trials have demonstrated that Zhongfeng Xingnao Liquid(ZFXN)ameliorates post-stroke cognitive impairment(PSCI).However,the underlying mechanism,particularly whether it involves protecting mitochondria and inhibiting apoptosis through the SIRT1/Nrf2/HO-1 pathway,remains unclear.This study employed an oxygen-glucose deprivation(OGD)cell model using SHSY5Y cells and induced PSCI in rats through modified bilateral carotid artery ligation(2VO).The effects of ZFXN on learning and memory,neuroprotective activity,mitochondrial function,oxidative stress,and the SIRT1/Nrf2/HO-1 pathway were evaluated both in vivo and in vitro.Results indicated that ZFXN significantly increased the B-cell lymphoma 2(Bcl2)/Bcl2-associated X(Bax)ratio,reduced terminal deoxynucleotidyl transferase-mediated d UTP nickend-labeling(TUNEL)+cells,and markedly improved cognition,synaptic plasticity,and neuronal function in the hippocampus and cortex.Furthermore,ZFXN exhibited potent antioxidant activity,evidenced by decreased ROS and malondialdehyde(MDA)content and increased superoxide dismutase(SOD),catalase(CAT),and glutathione(GSH)levels.ZFXN also demonstrated considerable enhancement of mitochondrial membrane potential(MMP),Tom 20 fluorescence intensity,adenosine triphosphate(ATP)and energy charge(EC)levels,and mitochondrial complexⅠandⅢactivity,thereby inhibiting mitochondrial damage.Additionally,ZFXN significantly increased SIRT1 activity and elevated SIRT1,nuclear Nrf2,and HO-1 levels.Notably,these effects were substantially counteracted when SIRT1 was suppressed by the inhibitor EX-527 in vitro.In conclusion,ZFXN alleviates PSCI by activating the SIRT1/Nrf2/HO-1 pathway and preventing mitochondrial damage. 展开更多
关键词 Zhongfeng Xingnao Liquid Post-stroke cognitive impairment Oxidative stress Mitochondrial function Apoptosis Sirtuin1/nuclear factor erythroid 2-related factor 2/heme oxygenase 1 pathway
原文传递
Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion
13
作者 Lu Guan Mengting Qiu +10 位作者 Na Li Zhengxiang Zhou Ru Ye Liyan Zhong Yashuang Xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying Du 《Neural Regeneration Research》 SCIE CAS 2025年第10期2838-2854,共17页
Pain is often comorbid with emotional disorders such as anxiety and depression.Hyperexcitability of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairme... Pain is often comorbid with emotional disorders such as anxiety and depression.Hyperexcitability of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid neurotransmission.This review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain disorders.Improving understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these conditions.However,the mechanisms that regulate gamma-aminobutyric acidergic systems remain elusive.It is also unclear as to whether the mechanisms are presynaptic or postsynaptic.Further exploration of the complexities of this system may reveal new pathways for research and drug development. 展开更多
关键词 anterior cingulate cortex ANXIETY chronic pain circuit communication COMORBIDITY depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission
暂未订购
Rock Joint Detection from Borehole Imaging Logs Using a Convolutional Neural Networks Model 被引量:1
14
作者 Yunfeng Ge Geng Liu +2 位作者 Haiyan Wang Huiming Tang Binbin Zhao 《Journal of Earth Science》 2025年第4期1700-1716,共17页
To map the rock joints in the underground rock mass,a method was proposed to semiautomatically detect the rock joints from borehole imaging logs using a deep learning algorithm.First,450 images containing rock joints ... To map the rock joints in the underground rock mass,a method was proposed to semiautomatically detect the rock joints from borehole imaging logs using a deep learning algorithm.First,450 images containing rock joints were selected from borehole ZKZ01 in the Rumei hydropower station.These images were labeled to establish ground truth which was subdivided into training,validation,and testing data.Second,the YOLO v2 model with optimal parameter settings was constructed.Third,the training and validation data were used for model training,while the test data was used to generate the precision-recall curve for prediction evaluation.Fourth,the trained model was applied to a new borehole ZKZ02 to verify the feasibility of the model.There were 12 rock joints detected from the selected images in borehole ZKZ02 and four geometric parameters for each rock joint were determined by sinusoidal curve fitting.The average precision of the trained model reached 0.87. 展开更多
关键词 rock joints automated detection borehole imaging deep learning YOLO model
原文传递
Xiahuo Pingwei San (夏藿平胃散) attenuated intestinal inflammation in dextran sulfate sodium-induced ulcerative colitis mice through inhibiting the receptor for advanced glycation end-products signaling pathway 被引量:1
15
作者 HUANG Jiaen LUO Qing +3 位作者 DONG Gengting PENG Weiwen HE Jianhong DAI Weibo 《Journal of Traditional Chinese Medicine》 2025年第2期311-325,共15页
OBJECTIVE:To evaluate the therapeutic effects of Xiahuo Pingwei San(夏藿平胃散,XHPWS)on ulcerative colitis(UC)in mice and to explore the underlying mechanisms through a network pharmacology approach.METHODS:Ultra-perf... OBJECTIVE:To evaluate the therapeutic effects of Xiahuo Pingwei San(夏藿平胃散,XHPWS)on ulcerative colitis(UC)in mice and to explore the underlying mechanisms through a network pharmacology approach.METHODS:Ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF/MS)was utilized to identify the chemical composition and authenticate the active constituents of XHPWS,ensuring rigorous quality control across batches.A dextran sulfate sodium(DSS)-induced UC model was established in C57BL/6 mice,which were treated with XHPWS in vivo.The efficacy against UC was assessed by measuring parameters such as body weight,disease activity index(DAI)scores,and colon length.Levels of inflammatory cytokines,including interleukin-6(IL-6),interleukin-1β(IL-1β),and tumor necrosis factor-alpha(TNF-α),in colonic tissue were evaluated using enzymelinked immunosorbent assay(ELISA).Histological analysis of colon sections was conducted using hematoxylin and eosin staining.A network pharmacology approach was employed to explore the mechanisms of XHPWS and to predict its potential targets in UC treatment.Predicted protein expressions in colonic tissue were validated using immune-ohistochemistry(IHC)and Western blotting techniques.RESULTS:XHPWS effectively alle via ted DSS-induced UC symptoms in mice,as evidenced by restored body weight,reduced colon shortening,and decreased DAI scores.Histopathological examination revealed that XHPWS significantly reduced intestinal inflammatory infiltration,restored intestinal epithelial permeability,and increased goblet cell count.Network pharmacology analysis identified 63 active compounds in XHPWS and suggested that it might target 35 potential proteins associated with UC treatment.Functional enrichment analysis indicated that the protective mechanism of XHPWS could be related to the advanced glycation end products-receptor for advanced glycation end products(AGE-RAGE)signaling pathway.Notably,quercetin,kaempferol,wogonin,and nobiletin,the main components of XHPWS,showed strong correlations with the core targets.Additionally,experimental validation demonstrated that XHPWS significantly decreased levels of inflammatory cytokines interleukin 6(IL-6),interleukin 1 beta(IL-1β),and tumor necrosis factor alpha(TNF-α)in UC mice,while downregulating the expression of proteins related to the AGE-RAGE pathway.CONCLUSION:Our study demonstrated that XHPWS effectively alle via tes colitis symptoms and inflammation in UC mice,potentially through the regulation of the AGE-RAGE pathway.These findings provide strong evidence for the therapeutic potential of XHPWS in UC treatment,thereby broadening its clinical applications. 展开更多
关键词 colitis ulcerative network pharmacology inflammation glycation end products advanced receptor for advanced glycation end products signal transduction Xiahuo Pingwei San
原文传递
Cross-section design of the flow channels in membrane electrode assembly electrolyzer for CO_(2) reduction reaction through numerical simulations 被引量:1
16
作者 Lili Zhang Hui Gao +7 位作者 Gong Zhang Yuning Dong Kai Huang Zifan Pang Tuo Wang Chunlei Pei Peng Zhang Jinlong Gong 《Chinese Chemical Letters》 2025年第1期332-337,共6页
Membrane electrode assembly(MEA)is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO_(2) reduction reaction(CO_(2)RR).In MEAs,a square-shaped cross-sec... Membrane electrode assembly(MEA)is widely considered to be the most promising type of electrolyzer for the practical application of electrochemical CO_(2) reduction reaction(CO_(2)RR).In MEAs,a square-shaped cross-section in the flow channel is normally adopted,the configuration optimization of which could potentially enhance the performance of the electrolyzer.This paper describes the numerical simulation study on the impact of the flow-channel cross-section shapes in the MEA electrolyzer for CO_(2)RR.The results show that wide flow channels with low heights are beneficial to the CO_(2)RR by providing a uniform flow field of CO_(2),especially at high current densities.Moreover,the larger the electrolyzer,the more significant the effect is.This study provides a theoretical basis for the design of high-performance MEA electrolyzers for CO_(2)RR. 展开更多
关键词 Electrochemical reduction of CO_(2) Membrane electrode assembly Mass transfer Gas diffusion electrode Computational fluid dynamics
原文传递
Recent Advances in Asymmetric Carbonylative Cross-Coupling Reactions
17
作者 Su Lei Yang Xi +4 位作者 Yan Jie Jiang Yuanli Chen Lijuan Zheng Qingshu Liu Jiawang 《有机化学》 北大核心 2025年第6期2007-2047,共41页
Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-c... Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-coupling reactions are among the most straightforward and effective methods for synthesizing chiral carbonyl compounds, including esters, amides, and ketones. The advances in asymmetric carbonylative cross-coupling reactions using various O-, N-, C-, and S-containing nucleophiles or electrophiles over the past decade are summarized. 展开更多
关键词 CARBONYLATION transition-metal catalysis asymmetric catalysis carbon monoxide cross-coupling reaction
原文传递
Preparation and effectiveness assessment of a recombinant IBV multiple antigenic peptide vaccine and laying hen yolk antibodies
18
作者 CHENG Jiahua WANG Zhuoling +8 位作者 ZHENG Min HE Xiaochan TIAN Yezi WANG Shuo WANG Ruirui WU Zhuoxuan FENG Yuanrui ZHANG Yuemeng YUE Changwu 《微生物学报》 北大核心 2025年第8期3731-3747,共17页
[Objective]To design and express a recombinant protein rMKIBV incorporating confirmed antigenic epitopes of infectious bronchitis virus(IBV)as a vaccine to provide comprehensive protection.Additionally,it explores the... [Objective]To design and express a recombinant protein rMKIBV incorporating confirmed antigenic epitopes of infectious bronchitis virus(IBV)as a vaccine to provide comprehensive protection.Additionally,it explores the potential of polyclonal yolk antibodies(IgY)harvested from laying hens immunized with the rMKIBV vaccine in the prevention and control of IBV.[Methods]The antigenic epitope sequences of IBV,obtained from online databases,were compared with sequences of representative IBV strains from GenBank.Flexible peptides were designed to link all antigenic peptides.The constructed amino acid sequence was analyzed,reverse-translated,codon-optimized,and then inserted into the pET-28a(+)cloning vector.The recombinant vector was introduced into Escherichia coli for expression.The purified,desalted,and endotoxin-removed rMKIBV protein was used as a vaccine to immunize animals for investigation of its immunogenicity and ability to stimulate specific IgY production in laying hens.[Results]The retrieved IBV antigenic epitope sequences showed high similarity with the published N and S protein sequences of 22 representative IBV strains.The predicted isoelectric point and molecular weight of rMKIBV were 10.25 and 63.39 kDa,respectively.The secondary structure of rMKIBV included a high proportion of random coils,which suggested strong antigenicity.High-purity rMKIBV was obtained from E.coli transformed with the recombinant plasmid pET-28a-mkibv.This protein specifically bound to anti-His-tag antibodies,N protein antibodies,and S protein antibodies.The mice immunized with this protein showed increases in the spleen index(P<0.05),elevations in the levels of serum-specific IgG antibodies(P<0.01)and IFN-γ(P<0.05),and no significant change in the IL-2 level.Immunized laying hens successfully produced IgY in egg yolks,with specific IgY antibody levels significantly increasing.Moreover,the IgY antibody titer gradually rose after immunization,reaching the peak after about 50 days and then gradually declining to reach a stable level.[Conclusion]We successfully constructed and expressed the recombinant protein rMKIBV.The protein demonstrated good immunogenicity,stimulating specific antibody production in both mice and laying hens.Notably,the IgY extracted from the yolks of immunized laying hens offers a novel approach to IBV prevention and control.These findings hold significant scientific and practical value for the development of vaccines against IBV. 展开更多
关键词 infectious bronchitis virus(IBV) vaccines recombinant fusion antigenic epitopes yolk antibody
原文传递
High-Voltage Solid-State Lithium Batteries: A Review of Electrolyte Design, Interface Engineering, and Future Perspectives
19
作者 Cheng Yang Zi-Xin Liang +3 位作者 Ming-Yun Zhang Ming-Zhe Chen Kai Zhang Li-Min Zhou 《电化学(中英文)》 北大核心 2025年第10期56-83,共28页
Solid-state lithium batteries have become a research hotspot in the field of large-scale energy storage due to their excellent safety performance.The development of high-voltage positive electrode materials matched wi... Solid-state lithium batteries have become a research hotspot in the field of large-scale energy storage due to their excellent safety performance.The development of high-voltage positive electrode materials matched with lithium metal anode have advanced the energy density of solid-state lithium batteries close to or even exceeding that of lithium batteries based on a liquid electrolyte,which is expected to be commercialized in the future.However,in high voltage conditions(>4.3 V),the decomposition of electrolyte components,structural degradation,and interface side reactions significantly reduce battery performance and hinder its further development.This review summarizes the latest research progress of inorganic electrolytes,polymer electrolytes,and composite electrolytes in high-voltage solid-state lithium batteries.At the same time,the designs of high-voltage polymer gel electrolyte and high-voltage quasi solid-state electrolyte are introduced in detail.In addition,interface engineering is crucial for improving the overall performance of high-voltage solid-state batteries.Finally,we highlight the challenges faced by high-voltage solid-state lithium batteries and put forward our own views on future research directions.This review offers instructive insights into the advancement of high-voltage solid-state lithium batteries for large-scale energy storage applications. 展开更多
关键词 Solid-state lithium batteries HIGH-VOLTAGE Solid-state electrolyte Interface engineering
在线阅读 下载PDF
Evaluation of three-dimensional structure modeling of key enzymes in endogenous catabolism of polyamines
20
作者 GUO Baolin XUE Qian +1 位作者 WANG Bing ZHAO Yuan 《化学研究》 2025年第3期268-277,共10页
The acetylpolyamine oxidase(APAO),spermine oxidase(SMO),and spermidine/spermine N1-acetyltransferase(SSAT)are pivotal enzymes in polyamine metabolism,exerting direct influence on polyamine homeostasis regulation.Dysfu... The acetylpolyamine oxidase(APAO),spermine oxidase(SMO),and spermidine/spermine N1-acetyltransferase(SSAT)are pivotal enzymes in polyamine metabolism,exerting direct influence on polyamine homeostasis regulation.Dysfunctions in these enzymes are intricately linked to inflammatory diseases and cancers.Establishing their three-dimensional structures is essential for exploring enzymatic catalytic mechanisms and designing inhibitors at the atomic level.This article primarily assesses the precision of AlphaFold2 and molecular dynamics simulations in determining the three-dimensional structures of these enzymes,utilizing protein conformation rationality assessment,residue correlation matrix,and other techniques.This provides robust models for subsequent polyamine catabolic metabolism calculations and offers valuable insights for modeling proteins that have yet to acquire crystal structures. 展开更多
关键词 AlphaFold2 molecular dynamics simulation polyamine metabolism ENZYME structure modeling
在线阅读 下载PDF
上一页 1 2 61 下一页 到第
使用帮助 返回顶部