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基于多元统计的反相破乳剂构效分析
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作者 李俊仪 李薛 +6 位作者 尹子超 魏旭 郑重 王景平 彭柳 田晨浩 郝昊天 《哈尔滨商业大学学报(自然科学版)》 2026年第2期233-239,共7页
通过多元统计方法系统评价了10种典型反相破乳剂的油水分离性能及宏观特性.综合运用物化表征与相关性分析、灰色关联度及主成分分析统计学手段,建立了反相破乳剂宏观特性参数与除油效能之间的构效关系.结果表明,不同反相破乳剂具有显著... 通过多元统计方法系统评价了10种典型反相破乳剂的油水分离性能及宏观特性.综合运用物化表征与相关性分析、灰色关联度及主成分分析统计学手段,建立了反相破乳剂宏观特性参数与除油效能之间的构效关系.结果表明,不同反相破乳剂具有显著差异的破乳效率,其中黏度和含脂肪烃量是关键控制因子;通过调控含脂肪烃量的反相破乳剂脱油对比实验证实,含脂肪烃量的提高可以显著促进脱油率.研究为定向合成高效反相破乳剂提供了设计依据,对优化原油采收液处理工艺具有重要工程指导价值. 展开更多
关键词 油田采出液 油水分离 反相破乳剂 灰色关联度 主成分分析
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Neuroserpin alleviates cerebral ischemia-reperfusion injury by suppressing ischemia-induced endoplasmic reticulum stress
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作者 Yumei Liao Qinghua Zhang +15 位作者 Qiaoyun Shi peng liu Peiyun Zhong Lingling Guo Zijian Huang Yinghui peng Wei liu Shiqing Zhang István Adorján Yumi Fukuzaki Eri Kawashita Xiao-Qi Zhang Nan Ma Xiaoshen Zhang Zoltán Molnár Lei Shi 《Neural Regeneration Research》 2026年第1期333-345,共13页
Neuroserpin,a secreted protein that belongs to the serpin superfamily of serine protease inhibitors,is highly expressed in the central nervous system and plays multiple roles in brain development and pathology.As a na... Neuroserpin,a secreted protein that belongs to the serpin superfamily of serine protease inhibitors,is highly expressed in the central nervous system and plays multiple roles in brain development and pathology.As a natural inhibitor of recombinant tissue plasminogen activator,neuroserpin inhibits the increased activity of tissue plasminogen activator in ischemic conditions and extends the therapeutic windows of tissue plasminogen activator for brain ischemia.However,the neuroprotective mechanism of neuroserpin against ischemic stroke remains unclear.In this study,we used a mouse model of middle cerebral artery occlusion and oxygen-glucose deprivation/reperfusion-injured cortical neurons as in vivo and in vitro ischemia-reperfusion models,respectively.The models were used to investigate the neuroprotective effects of neuroserpin.Our findings revealed that endoplasmic reticulum stress was promptly triggered following ischemia,initially manifesting as the acute activation of endoplasmic reticulum stress transmembrane sensors and the suppression of protein synthesis,which was followed by a later apoptotic response.Notably,ischemic stroke markedly downregulated the expression of neuroserpin in cortical neurons.Exogenous neuroserpin reversed the activation of multiple endoplasmic reticulum stress signaling molecules,the reduction in protein synthesis,and the upregulation of apoptotic transcription factors.This led to a reduction in neuronal death induced by oxygen/glucose deprivation and reperfusion,as well as decreased cerebral infarction and neurological dysfunction in mice with middle cerebral artery occlusion.However,the neuroprotective effects of neuroserpin were markedly inhibited by endoplasmic reticulum stress activators thapsigargin and tunicamycin.Our findings demonstrate that neuroserpin exerts neuroprotective effects on ischemic stroke by suppressing endoplasmic reticulum stress. 展开更多
关键词 endoplasmic reticulum stress ischemia-reperfusion injury NEURON neuronal apoptosis NEUROPROTECTION NEUROSERPIN protein synthesis secretory protein stroke transcriptomic analysis
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Transplantation of human neural stem cells repairs neural circuits and restores neurological function in the stroke-injured brain
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作者 Peipei Wang peng liu +7 位作者 Yingying Ding Guirong Zhang Nan Wang Xiaodong Sun Mingyue Li Mo Li Xinjie Bao Xiaowei Chen 《Neural Regeneration Research》 2026年第3期1162-1171,共10页
Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after inju... Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients. 展开更多
关键词 behavioral recovery circuit repair electrophysiological properties functional integration human neural stem cell transplantation infarction volume STROKE synaptic tracing
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Clinical-transcriptomic classification of lumbar disc degeneration enhanced by machine learning
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作者 Huai-Jian Jin peng Lin +17 位作者 Xiao-Yuan Ma Sha Huang Liang Zhang Ou Hu Yang-Yang Li Ying-Bo Wang Jun Zhu Bo Hu Jun-Gang Pu Qin Qin Pu-Lin Yan Bing liu Yu Lan Lin Chen Yang-Li Xie Jian He Yi-Bo Gan peng liu 《Military Medical Research》 2026年第1期58-77,共20页
Background:Lumbar disc degeneration(LDD)displays considerable heterogeneity in terms of clinical features and pathological changes.However,researchers have not clearly determined whether the transcriptome variations i... Background:Lumbar disc degeneration(LDD)displays considerable heterogeneity in terms of clinical features and pathological changes.However,researchers have not clearly determined whether the transcriptome variations in LDD could be used to identify or interpret the causes of heterogeneity in clinical features.This study aimed to identify the transcriptomic classification of degenerated discs in LDD patients and whether the molecular subtypes of LDD could be accurately predicted using clinical features.Methods:One hundred and twenty-two nucleus pulposus(NP)tissues from 108 patients were consecutively collected for bulk RNA sequencing(RNA-seq).An unsupervised clustering method was employed to analyze the bulk RNA matrix.Differential analysis was performed to characterize the transcriptional signatures and subtype-specific extracellular matrix(ECM)dysregulation.The cell subpopulation states of each subtype were inferred by integrating bulk and single-cell sequencing datasets.Transwell and dual-luciferase reporter gene assays were employed to investigate possible molecular mechanisms involved.Machine learning algorithm diagnostic prediction models were developed to correlate molecular classification with clinical features.Results:LDD was classified into 4 subtypes with distinct molecular signatures and ECM remodeling:C1 with collagenesis,C2 with ossification,C3 with low chondrogenesis,and C4 with fibrogenesis.Chond1-3 in C1 dominated disc collagenesis via the activation of the mechanosensors TRPV4 and PIEZO1;NP progenitor cells in C2 exhibited chondrogenic and osteogenic phenotypes;Chond1 in C3 was linked to a disrupted hypoxic microenvironment leading to reduced chondrogenesis;Macrophages in C4 played a crucial role in disc fibrogenesis via the secretion of tumor necrosis factor-α(TNF-α).Furthermore,the random forest diagnostic prediction model was proven to have a robust performance[area under the receiver operating characteristic(ROC)curve:0.9312;accuracy:0.84]in stratifying the molecular subtypes of LDD based on 12 clinical features.Conclusions:Our study delineates 4 distinct molecular subtypes of LDD that can be accurately stratified on the basis of clinical features.The identification of these subtypes would facilitate precise diagnostics and guide the development of personalized treatment strategies for LDD. 展开更多
关键词 Lumbar disc degeneration(LDD) Molecular classification Machine learning Diagnosis TRANSCRIPTOME RNA sequencing(RNA-seq)
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Promotion of electrolytic ethylene production in acidic media through a single-atom cocatalyst:The dual role in inhibiting hydrogen evolution and boosting C–C coupling
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作者 Wei Hua Xiya Yang +8 位作者 Zhangyi Zheng Mutian Ma Kun Feng Daqi Song peng liu Fenglei Lyu Jun Zhong Zhao Deng Yang peng 《Journal of Energy Chemistry》 2026年第3期277-286,共10页
Electrocatalytic CO_(2)reduction(eCO_(2)R)in acidic electrolytes is propitious to enhance CO_(2)utilization,yet suffering from low current efficiency due to the rapid kinetics of the competing hydrogen evolution react... Electrocatalytic CO_(2)reduction(eCO_(2)R)in acidic electrolytes is propitious to enhance CO_(2)utilization,yet suffering from low current efficiency due to the rapid kinetics of the competing hydrogen evolution reaction(HER),especially under high current densities.This study proposes the implementation of a singleatom NiNC cocatalyst concurrently generating CO and releasing OH^(-)to neutralize H^(+)in the electrolyte,thereby simultaneously suppressing HER and promoting C–C coupling.By homogeneously mixing the NiNC cocatalyst with Cu nanoparticles(NPs),as opposed to a stratified configuration,a high ethylene Faradaic efficiency(FE)of 57%was achieved at 600 mA cm^(-2)in acidic media,along with a remarkable single-pass CO_(2)conversion efficiency of 52.4%.While rotating disk electrode tests and operando Raman spectroscopy attest to the restricted H^(+)diffusion and elevated local pH near the catalyst surface,in situ Infrared and differential electrochemical mass spectrometries corroborate the spillover of CO from the cocatalyst to neighboring Cu NPs for enhanced C–C coupling.This work offers new insights into the design and application principles of compositional eCO_(2)R catalysts for promoting multicarbon synthesis in acidic media at high current density. 展开更多
关键词 CO_(2)reduction Acidic electrolyte COCATALYST Proton neutralization CO spillover
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Bifunctional separators for safe Li metal batteries:Uniform fluorination interface engineering and flame retardancy
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作者 peng liu Tianle Li +5 位作者 Yupeng Xiao Jiyuan You Bo Zhang Yunjia liu Wenju Wang Yuqian Li 《Journal of Energy Chemistry》 2026年第2期217-227,I0007,共12页
Traditional fluorination strategies have attracted significant attention due to their ability to construct a fluorine-rich solid-electrolyte interphase(SEI)at the anode-electrolyte interface.However,the inhomogeneous ... Traditional fluorination strategies have attracted significant attention due to their ability to construct a fluorine-rich solid-electrolyte interphase(SEI)at the anode-electrolyte interface.However,the inhomogeneous distribution of LiF within the SEI layer remains a critical challenge that hinders the effective suppression of lithium dendrite growth.This work explores the synergy between HDBDPE(degradation products of decabromodiphenyl ethane)and MgF_(2),developing a fluorinated,flame-retardant separator with optimized ion channels,HDBDPE acts as both a low-toxicity flame retardant and an"F-element guide"through hydrogen bonding with MgF_(2),forming a uniform LiF SEI layer on the Li anode for rapid reaction kinetics.Moreover,under thermal runaway conditions,the MgF_(2)@HDBDPE/PP separator constructs a"high-efficiency flame-retardant barrier",effectively quenching free radicals and promoting the formation of MgBr_(2),thereby suppressing electrolyte combustion.As a result,both symmetric and full cells assembled with the MgF_(2)@HDBDPE/PP separator demonstrate superior cyclic stability and rate performance due to improved interfacial reactions.The MgF_(2)@HDBDPE/PP separator exhibits rapid flame retardancy under thermal runaway conditions. 展开更多
关键词 Dendrite growth Multifunctional separators Hydrogen bonds LiF distribution Flame retardant
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Near-infrared light activatable nanoplatform for proteins labeling,enrichment and visualization in living systems
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作者 peng liu Shengli Zhang +8 位作者 Tingting Zhang Yu Si Ziang liu Xiao Qian Yingxu Wu Yuan Liang Wen Sun Engin U.Akkaya Lei Wang 《Chinese Chemical Letters》 2026年第1期421-426,共6页
The study of target proteins is crucial for understanding molecular interactions and developing analytical platforms,therapeutic agents and functional tools.Herein,we present a novel nanoplatform activated by near-inf... The study of target proteins is crucial for understanding molecular interactions and developing analytical platforms,therapeutic agents and functional tools.Herein,we present a novel nanoplatform activated by near-infrared(NIR) light for triple-modal proteins study,which enabling target protein labeling,enrichment and visualization.Azido-naphthalimide-coated upconversion nanoparticles(UCNPs) serve as NIR light-responsive nanoplatforms,showing promising applications in studying interactions between various bioactive molecules and proteins in living systems.Under NIR light irradiation,azido-naphthalimides are activated by ultraviolet(UV) and blue light emitted from UCNPs and the resulting amino-naphthalimides intermediate not only crosslink nearby target proteins but also enable imaging performance.We demonstrate that this nanoplatform is capable of selective protein labeling and imaging in complex protein environments,achieving specific labeling and imaging of both intracellular and extracellular proteins in mammalian cells as well as bacteria.Furthermore,in vivo protein labeling has been achieved using this novel NIR light-activatable nanoplatform.This technique will open new avenues for discoveries and mechanistic interrogation in chemical biology. 展开更多
关键词 Fluorescent probes Protein labeling Near-infrared light Upconversion nanoparticles Cell imaging
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Asymmetric construction of non-activated C-SCF_(3) stereocenter via copper-catalyzed hydroallylation of SCF_(3)-alkenes
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作者 Wei-Cheng Zhao Yan He +4 位作者 Chen-Hui Jiang peng liu Qian Gao Duo-Duo Hu Xi-Sheng Wang 《Chinese Chemical Letters》 2026年第2期424-429,共6页
Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical ... Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical research and development.While extensive research has been devoted to constructing molecules that incorporate a trifluoromethylthio(SCF_(3)−)group on a stereogenic carbon,the synthesis of trifluoromethylthiolated alkanes featuring a SCF_(3)-substituted stereogenic carbon at non-activated site remains understudied.Herein,we report a Cu-catalyzed regio-and enantioselective hydroallylation of 1-trifluoromethylthiolated alkenes.Important to the process is the regio-and enantioselective Cu-H insertion to SCF_(3)-substituted alkene to form chiralα-SCF_(3) alkyl copper intermediates,outcompeting unproductive insertion to the coupling partner,and eventually proceed to afford optically active homoallylic trifluoromethylthiolated products. 展开更多
关键词 Asymmetric construction Non-activated Hydroallylation Trifluoromethylthio group COPPER-CATALYZED
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Effect of“inert barrier layer”Ni on electron emission performance of dispenser cathode
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作者 Zheng liu Yunfei Yang +4 位作者 peng liu Junhao Sun Hexiong liu Yongfeng Cai Jinshu Wang 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期683-692,共10页
A novel trace nickel(Ni)doped tungsten(W)matrix with coated Ni on W grains was prepared by powder metallurgy method.The introduction of Ni can inhibit the reaction between W and barium-calcium aluminates(Ba-Ca alumina... A novel trace nickel(Ni)doped tungsten(W)matrix with coated Ni on W grains was prepared by powder metallurgy method.The introduction of Ni can inhibit the reaction between W and barium-calcium aluminates(Ba-Ca aluminates)during the impregnation process of the matrix.After cathode activation,the surface Ba:O molar ratio is 0.88:1.00,much higher than the Ba dispenser cathode without Ni doping.The XPS results of the cathode surface showed that the metallic Ba appeared on the activated cathode surface,forming dipoles with oxygen,and effectively reducing the cathode surface work function.The pulse electron emission current density at 1100℃_(b)(brightness temperature)was 18.26 A/cm^(2),and the calculated work function was 1.97 eV.It has a low evaporation rate and the accelerated lifetime test predict a lifetime of over 160000 h.First-principles calculations showed that the charge transfer and dipole moment in the NiW-BaO system were both increased compared to the Ba dispenser cathode,thus improving the emission performance of the Ni-W mixed matrix cathode. 展开更多
关键词 NICKEL inert barrier layer PASSIVATION EVAPORATION dispenser cathode
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Enhancing yield of modern maize(Zea mays L.)hybrids through optimization of population photosynthetic capacity and light-nitrogen use efficiency under high planting density
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作者 Zhenlong Wang Pin He +7 位作者 Xuyao Li Tieshan liu Saud Shah Hao Ren Baizhao Ren peng liu Jiwang Zhang Bin Zhao 《Journal of Integrative Agriculture》 2026年第3期938-951,共14页
In maize production,the development of density-tolerant and lodging-resistant varieties has made dense planting an effective strategy for achieving high and stable yields,with superior hybrids serving as a prerequisit... In maize production,the development of density-tolerant and lodging-resistant varieties has made dense planting an effective strategy for achieving high and stable yields,with superior hybrids serving as a prerequisite for successful highdensity cultivation.However,the photosynthetic mechanisms underlying improved density tolerance in maize hybrids released across different eras in China remain unclear.This study investigates 40 years of breeding progress toward enhanced photosynthetic traits under varying planting densities and elucidates the physiological and ecological bases of improved density tolerance in maize hybrids.A three-year field experiment was conducted from 2019 to 2021 to compare eight major Chinese hybrids from four decadal cohorts under three planting densities:45,000(D1),67,500(D2),and 90,000(D3)plants ha^(-1).At high density(D3),modern hybrids exhibited a more optimal canopy architecture and superior leaf photosynthetic performance compared to older hybrids,despite a slight reduction in specific leaf nitrogen.Notably,modern hybrids(2000s)were able to maintain higher net photosynthetic rates and photosynthetic nitrogen use efficiency(PNUE)at D3,resulting in the highest grain yield(GY),which was 118.47%greater than that of older hybrids(1970s).Leaf area duration after anthesis,total chlorophyll content,key photosynthetic enzyme activities,and maximum quantum efficiency of PSII photochemistry were all positively correlated with GY.Among these,PNUE showed the strongest correlation with grain yield and thus represents a key indicator for optimizing maize hybrids.Based on these findings,breeders should continue selecting hybrids under high-density and suboptimal conditions,focusing on optimizing population architecture and enhancing photosynthetic capacity while fine-tuning leaf nitrogen status to develop high-yielding,density-tolerant hybrids capable of sustaining long-term increases in maize grain yield. 展开更多
关键词 maize hybrids planting density photosynthetic characteristics photosynthetic use efficiency grain yield
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Cross-scale investigation of overcharge-induced thermal runaway propagation mechanism in sodium-ion batteries under multi-module configuration
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作者 Qinghua Gui Jinzhong Li +4 位作者 Bowen Jin peng liu Kun Yu Jiarui Zhang Lei Mao 《Journal of Energy Chemistry》 2026年第1期13-28,I0002,共17页
In electrochemical energy storage systems,the sodium-ion battery is typically integrated in the form of a“cell-module-cluster”,but its cross-scale thermal runaway triggering risk and the propagation mechanism remain... In electrochemical energy storage systems,the sodium-ion battery is typically integrated in the form of a“cell-module-cluster”,but its cross-scale thermal runaway triggering risk and the propagation mechanism remain unclear.This study reveals the cross-scale thermal runaway triggering and propagation behavior of sodium-ion batteries of“cell-module-cluster”under overcharge conditions,and investigates the effects of key factors,including module spacing,triggering cell location,and heat dissipation condition,on the thermal runaway propagation behavior.Results demonstrate that the thermal runaway propagation in a module containing the overcharged cell follows a sequential triggering mode,while thermal runaway in the downstream module exhibits a simultaneous triggering mode with greater severity.Furthermore,increasing the module spacing or enhancing the heat dissipation capacity can effectively reduce the heat accumulation and prevent the trigger of thermal runaway.On the above basis,the multi-dimensional evaluation strategy is proposed to quantitatively assess the hazard of sodium-ion battery cluster thermal runaway.The findings serve as a foundation for the safe design of sodium-ion batteries in energy storage systems. 展开更多
关键词 Cross-scale Sodium-ion battery OVERCHARGE Thermal runaway Propagation mechanism
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MitoQ alleviates m.3243A>G-induced mitochondrial dysfunction by stabilizing PINK1 and enhancing mitophagy
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作者 Baige Cao Lei Fang +7 位作者 Yinan Zhang Chuwen Lin peng liu Huina Zhang Orion Fan Ming Xu Zhao Qin Congrong Wang 《Journal of Genetics and Genomics》 2026年第3期476-487,共12页
The mitochondrial 3243A>G mutation(m.3243A>G)is associated with diverse clinical phenotypes.To elucidate the underlying mechanisms and explore intervention strategies in m.3243A>G patients,urine-derived stem ... The mitochondrial 3243A>G mutation(m.3243A>G)is associated with diverse clinical phenotypes.To elucidate the underlying mechanisms and explore intervention strategies in m.3243A>G patients,urine-derived stem cells(USCs)and a mitochondrial leucyl-tRNA synthetase gene(lars-2)deficient Caenorhabditis elegans(C.elegans)model are used to assess mitochondrial homeostasis and neuromuscular dysfunction.Patient-derived USCs with high levels of m.3243A>G heteroplasmy exhibit impaired mitochondrial function,disrupted mitochondrial dynamics,and inhibited mitophagy,which are reversed by MitoQ through suppression of OMA1 zinc metallopeptidase(OMA1)-induced mitochondrial phosphatase and tensin(PTEN)induced kinase 1(PINK1)degradation.Furthermore,lars-2 knockdown in C.elegans induces mitochondrial stress and mimics the loss of neural and muscle functions observed in patients with the m.3243A>G mutation.MitoQ treatment partially improves neurobehavioral function by promoting the PINK1 pathway.These findings suggest that MitoQ has therapeutic potential in the context of the m.3243A>G mutation. 展开更多
关键词 m.3243A>G USCs Mitochondrial quality control MITOQ C.elegans
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Shading and waterlogging interactions exacerbate summer maize yield losses by reducing assimilate accumulation and remobilization processes
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作者 Qinghao Wang Juan Hu +6 位作者 Weizhen Yu Limin Gu peng liu Bin Zhao Wenchao Zhen Jiwang Zhang Baizhao Ren 《Journal of Integrative Agriculture》 2026年第1期92-104,共13页
Persistent overcast rain was an essential limiting factor for summer maize production,of which immediate impact was the dual pressure of waterlogging and shading.However,the mechanisms underlying independent and combi... Persistent overcast rain was an essential limiting factor for summer maize production,of which immediate impact was the dual pressure of waterlogging and shading.However,the mechanisms underlying independent and combined effects of waterlogging and shading on maize yield losses remain understudied,particularly across different growth stages.Denghai 605(DH605)was selected to be subjected shading,waterlogging,and their combined stress at the 3rd leaf stage(V3),the 6th leaf stage(V6),and tasseling stage(VT).Results showed that shading,waterlogging and their combination significantly restricted leaf area expansion,reduced leaf net photosynthetic rate(P_(n))and net assimilation rate(NAR),thereby decreasing the crop growth rate(CGR)and biomass accumulation.Additionally,compared to control,the process of lignin synthesis was inhibited under stressed treatment,resulting in diminished stem mechanical strength and impaired vascular system development,which substantially reduced assimilate remobilization efficiency to the ear and ultimate grain yield.Waterlogging and combined stresses exhibited maximum impact at the V3 stage,followed by V6 and VT stages,while shading effects were most pronounced at the VT stage,followed by V6 and V3 stages.Moreover,the compound stress exacerbated the damage brought about by a single stress.As climate change is projected to increase the frequency of multiple abiotic stress occurrences,these findings provide valuable insights for future summer maize breeding research under persistent rainfall conditions. 展开更多
关键词 MAIZE abiotic stress combination photosynthetic capacity stem development YIELD
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Intramolecular carbon isotopic fractionation of propane via thermochemical sulfate reduction(TSR)in natural gas reservoirs
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作者 peng liu Xiaofeng Wang +7 位作者 Hanlin liu Juske Horita Guoxiao Zhou Hongping Bao Ying Lin Ruiliang Guo Dongdong Zhang Wenhui liu 《Natural Gas Industry B》 2026年第1期1-8,共8页
Thermochemical sulfate reduction(TSR)is an important organic-inorganic reaction that occurs within sedimentary basins and alters the original chemical compositions and isotopic structures of hydrocarbons in natural ga... Thermochemical sulfate reduction(TSR)is an important organic-inorganic reaction that occurs within sedimentary basins and alters the original chemical compositions and isotopic structures of hydrocarbons in natural gases.We used the GC-Py-GC-IRMS method to study TSR and obtained a novel finding related to intramolecular carbon isotope fractionation in natural propane.The results show that theΔC-T(δ^(13)C_(central)-13 C_(terminal))andδ^(13)C_(central)values significantly increased to 44.7‰and 11.9‰,respectively,with increasing TSR alteration.In contrast,the 13 C_(terminal)values of propane remained largely unaltered by the TSR reaction.This difference in position-specific isotope fractionation can be attributed to the central carbon’s reactivity being higher than that of terminal carbon during TSR.In sum,the results indicate that theδ^(13)C_(terminal)values of propane can serve as robust indicators for source rock identification of natural gas altered by post-generation reactions such as TSR and anaerobic microbial oxidation. 展开更多
关键词 Thermochemical sulfate reduction(TSR) Hydrocarbons PROPANE Position-specific isotope
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Urban expansion drives both loss and compensation in city vegetation productivity
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作者 Xinyue liu Tianshan Zha +6 位作者 Charles P.-A.Bourque peng liu Hongxian Zhao Tingshan Li Xinhao Li Yun Tian Xin Jia 《Journal of Environmental Sciences》 2026年第2期591-599,共9页
Urbanization alters vegetation productivity by both direct(ωd)and indirect(ω_(i))effects.The direct effect is from the change of vegetated area indicated by impervious surface intensity(ISI),while indirect effects a... Urbanization alters vegetation productivity by both direct(ωd)and indirect(ω_(i))effects.The direct effect is from the change of vegetated area indicated by impervious surface intensity(ISI),while indirect effects arise from changes in urban environmental factors,such as near-surface air temperatures,precipitation,urban heat island(UHI)intensity,and population density(POP).The respective contributions ofω_(d) andω_(i) to vegetation net primary productivity(NPP)under various phases of urbanization are not well quantified.Using multisource remote-sensing data from 1990 to 2020,we analyzed the spatiotemporal variation in urban expansion and the effect thatω_(d) andω_(i) had on NPP in the megalopolis of Beijing,China,over 5-year intervals.During this period,Beijing underwent significant planar expansion rates of about 58.9 km^(2)/yr.Annual mean loss of NPP byω_(d) was estimated to be about 77.1 g C/(m^(2)·yr)during the 1990-2020 period,while annual mean improvement to NPP byω_(i) amounted to an increase of 28.9 g C/(m^(2)·yr).The NPP losses were partially offset by NPP improvements in the order of 18.6%-69.3%.The impact of forcing variables on NPP varied spatially.Air temperature,precipitation,UHI,POP,and ISI explained about 13.8%,23.2%,23.7%,14.7%,and 24.6%of the spatial variation in NPP.The impact of air temperature on NPP was related to available moisture,negatively affecting NPP in regions with water deficits.Our findings demonstrate the dual impact of urbanization on vegetation and underscore the necessity for spatially adaptive ecological management strategies in regions experiencing rapid urban growth. 展开更多
关键词 Impervious surface intensity Vegetation productivity COMPENSATION Spatial heterogeneity
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Lightweight Complex-Valued Neural Network for Indoor Positioning
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作者 Le Wang Bing Xu +1 位作者 peng liu En Yuan 《Computers, Materials & Continua》 2026年第2期1770-1783,共14页
Deep learning has been recognized as an effective method for indoor positioning.However,most existing real-valued neural networks(RVNNs)treat the two constituent components of complex-valued channel state information(... Deep learning has been recognized as an effective method for indoor positioning.However,most existing real-valued neural networks(RVNNs)treat the two constituent components of complex-valued channel state information(CSI)as real-valued inputs,potentially discarding useful information embedded in the original CSI.In addition,existing positioning models generally face the contradiction between computational complexity and positioning accuracy.To address these issues,we combine graph neural network(GNN)with complex-valued neural network(CVNN)to construct a lightweight indoor positioning model named CGNet.CGNet employs complexvalued convolution operation to directly process the original CSI data,fully exploiting the correlation between real and imaginary parts of CSI while extracting local features.Subsequently,the feature values are treated as nodes,and conditional position encoding(CPE)module is applied to add positional information.To reduce the number of connections in the graph structure and lower themodel complexity,feature information is mapped to an efficient graph structure through a dynamic axial graph construction(DAGC)method,with global features extracted usingmaximum relative graph convolution(MRConv).Experimental results show that,on the CTW dataset,CGNet achieves a 10%improvement in positioning accuracy compared to existing methods,while the number of model parameters is only 0.8 M.CGNet achieves excellent positioning accuracy with very few parameters. 展开更多
关键词 Indoor positioning complex-valued neural network channel state information lightweight model
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LSTM-GRU and Multi-Head Attention Based Multivariate Time Series Prediction Model for Electro-Hydraulic Servo Material Fatigue Testing Machine
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作者 Guotai Huang Xiyu Gao +1 位作者 peng liu Liming Zhou 《Computers, Materials & Continua》 2026年第5期298-314,共17页
To address the insufficient prediction accuracy of multi-state parameters in electro-hydraulic servo material fatigue testing machines under complex loading and nonlinear coupling conditions,this paper proposes a mult... To address the insufficient prediction accuracy of multi-state parameters in electro-hydraulic servo material fatigue testing machines under complex loading and nonlinear coupling conditions,this paper proposes a multivariate sequence-to-sequence prediction model integrating a Long Short-Term Memory(LSTM)encoder,a Gated Recurrent Unit(GRU)decoder,and a multi-head attention mechanism.This approach enhances prediction accuracy and robustness across different control modes and load spectra by leveraging multi-channel inputs and cross-variable feature interactions,thereby capturing both short-term high-frequency dynamics and long-term slow drift characteristics.Experiments using long-term data from real test benches demonstrate that the model achieves a stable MSE below 0.01 on the validation set,with MAE and RMSE of approximately 0.018 and 0.052,respectively,and a coefficient of determination reaching 0.98.This significantly outperforms traditional identification methods and single RNN models.Sensitivity analysis indicates that a prediction stride of 10 achieves an optimal balance between accuracy and computational overhead.Ablation experiments validated the contribution of multi-head attention and decoder architecture to enhancing cross-variable coupling modeling capabilities.This model can be applied to residualdriven early warning in health monitoring,and risk assessment with scheme optimization in test design.It enables near-real-time deployment feasibility,providing a practical data-driven technical pathway for reliability assurance in advanced equipment. 展开更多
关键词 Fatigue testing machines multivariate time series prediction LSTM-GRU
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Constitutive expression of a chrysanthemum phospholipase Dα gene in Chrysanthemum morifolium enhances drought tolerance 被引量:1
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作者 Lisheng Zhai Xiaochen Zhu +8 位作者 Shujin Yang Chunsun Gu peng liu Aiping Song Jiafu Jiang Zhiyong Guan Weimin Fang Fadi Chen Sumei Chen 《Ornamental Plant Research》 2021年第1期68-77,共10页
Drought causes water shortage and consequent retardation of plants growth and development.Therefore,improving the drought tolerance of plants is necessary for expanding cultivation and resource promotion.Increasing ev... Drought causes water shortage and consequent retardation of plants growth and development.Therefore,improving the drought tolerance of plants is necessary for expanding cultivation and resource promotion.Increasing evidence indicates that phospholipase is involved in the response of plants to drought stress.The objective of this study was to create new drought-tolerant chrysanthemum germplasm,which lays a foundation for the study of the molecular mechanism of phospholipase mediated stress response in chrysanthemum.CmPLDαhas the closest relationship with sunflower HaPLDα,and belongs to the PLDαfamily.CmPLDαover-expressing plants showed a slight shrinking under 20%PEG6000 treatment.The survival rate increased significantly by 1.7−1.8 times that of the wild type.Relative water content(RWC)of CmPLDαover-expressing plants were nearly 10%higher than that of the wild type.Relative electrical conductivity and MDA content were significantly lower than those of the wild type.ABA content of the over-expression lines Z1,Z2 were 1.3 and 1.22 times that of wild type,but ABA content of antisense lines F1,F2 was approximately 0.83 and 0.81 of those of wild type.Most plants of antisense transgenic lines F1,F2 were wrinkled,with a wilting index of 5 and 6,and the survival rate was also lower than that of the wild type after recovery growth.RWC of antisense lines were lower than over-expression lines,relative electrical conductivity and MDA content were significantly higher than those of the wild type.In summary,CmPLDαcould enhance tolerance of chrysanthemum to drought conditions. 展开更多
关键词 DROUGHT EXPRESSING TOLERANCE
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雷公藤红素促进癌旁脂肪细胞分泌脂联素抗肾透明细胞癌上皮间充质转化作用 被引量:1
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作者 何鹏 张婵娟 +4 位作者 石雅宁 朱能 陈聪 彭柳 覃丽 《中南药学》 2025年第3期638-643,共6页
目的探讨雷公藤红素(CeT)诱导癌旁脂肪细胞分泌脂联素(APN)抑制人肾透明细胞癌细胞株786-O增殖迁移的作用机制。方法通过CCK 8法检测CeT对786-O和3T3-L1细胞的毒性,诱导3T3-L1分化并采用油红O染色检测3T3-L1细胞分化情况,通过ELISA检测... 目的探讨雷公藤红素(CeT)诱导癌旁脂肪细胞分泌脂联素(APN)抑制人肾透明细胞癌细胞株786-O增殖迁移的作用机制。方法通过CCK 8法检测CeT对786-O和3T3-L1细胞的毒性,诱导3T3-L1分化并采用油红O染色检测3T3-L1细胞分化情况,通过ELISA检测不同浓度CeT对于3T3-L1细胞分化后的成熟脂肪细胞分泌脂联素情况。建立786-O和3T3-L1细胞共培养体系,采用划痕实验、EDU检测共培养体系对786-O细胞增殖、迁移能力的影响,并采用Western blot法检测上皮间充质转化(EMT)相关蛋白(E-cad、N-cad、Snail、Vim)、Adiponectin等相关蛋白的表达。结果50、100、200 nmol·L^(-1)的CeT可刺激成熟脂肪细胞分泌脂联素,抑制肾癌细胞增殖和迁移;共培养后786-O细胞中EMT相关蛋白N-cad、Snail、Vim的表达水平显著下调,E-cad表达水平上升。结论CeT通过诱导脂肪细胞分泌脂联素抑制肾透明细胞癌EMT进程。 展开更多
关键词 雷公藤红素 肾透明细胞癌 脂联素 共培养
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土壤环境因子对荒漠植物叶性状的驱动机制
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作者 琚晓千 田赟 +6 位作者 徐铭泽 代远萌 李满乐 周煜涵 刘鹏 贾昕 查天山 《生物多样性》 北大核心 2025年第11期153-168,共16页
植物性状是连接植物与环境之间的桥梁,功能群作为研究其关系的基本单元,承载着响应环境变化的主要信息。研究植物功能群组成和叶性状如何随资源梯度变化,对于理解荒漠植物的环境适应策略至关重要。本研究以毛乌素沙地黑沙蒿(Artemisia o... 植物性状是连接植物与环境之间的桥梁,功能群作为研究其关系的基本单元,承载着响应环境变化的主要信息。研究植物功能群组成和叶性状如何随资源梯度变化,对于理解荒漠植物的环境适应策略至关重要。本研究以毛乌素沙地黑沙蒿(Artemisia ordosica)群落为研究对象,选取4个典型恢复阶段(D1:半固定沙地;D2:固定沙地;D3:土壤生物结皮固定沙地;D4:草本植物固定沙地),重点分析了不同植物功能群(禾本科、非禾本科和灌木)叶性状与物种组成的阶段性演变规律,并探讨了影响二者变化的主要土壤环境因子。结果表明:随着沙地逐步固定,植物功能群组成趋于复杂化,其中禾本科和非禾本科种类和数量增加,而灌木则无明显变化。D1、D2阶段植物功能群叶性状表现为较高的比叶面积和较低的叶干物质含量(leaf dry matter content,LDMC),表明植物优先投资叶片形态建成以提高资源利用能力;禾本科具有较高的LDMC和碳同化能力,适应胁迫环境的能力更强。冗余分析结果表明,土壤含水量(soil water content,SWC)、土壤碳氮比(soil carbon to nitrogen ratio,SC:SN)和土壤有机碳含量(soil organic carbon content,SOC)对3种植物功能群叶性状影响极显著(P<0.01)。方差分解和层次分割分析显示,9个土壤环境因子解释了植物叶性状总变差的18.5%,其中SC:SN的单独效应最大(4.13%),且SC:SN和SWC与大多数因子存在共同效应。本研究综合运用多种统计分析方法,系统识别了荒漠植物性状变异的关键土壤驱动因子及其协同效应,为区域植被恢复和生态系统可持续管理提供了坚实的理论基础。 展开更多
关键词 叶性状 土壤环境因子 冗余分析 固沙阶段 植物功能群
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