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Role of bioengineering structures made of willow cuttings in marly sediment trapping: assessment of three real-size experiments in the Southern French Alps 被引量:1
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作者 Freddy REY 《Journal of Mountain Science》 SCIE CSCD 2018年第2期225-236,共12页
Improving knowledge on the ability of bioengineering structures made of willow cuttings to enhance efficient and sustainable sediment trapping in marly gullies in the Southern French Alps under a mountainous Mediterra... Improving knowledge on the ability of bioengineering structures made of willow cuttings to enhance efficient and sustainable sediment trapping in marly gullies in the Southern French Alps under a mountainous Mediterranean climate, to decreasesediment trapped per experiment, the mean annual values reached 0.25, 0.14 and 0.08 m3 yr-1 in experiments C, A and B, respectively. Maximum values for one structure reached 1.94 m3 per year in experiment C. The significance of the volumes ofsediment yield at their outlets, is a key issue today for the international scientific community working in geosciences and ecology. This study therefore aims to assess three real-size experiments(A, B and C) carried out between 2003 and 2013 in this environment. A total of 157 bioengineering structures using purple and white willow(Salix purpurea and Salix incana)cuttings – which have been shown to resprout and survive more than 2 years after their installation,corresponding to brush layers with brush mats on wooden sills(BLM), 1.2 m wide and 2 m long,installed on the floors of 33 experimental marly gullies, were monitored. The results showed that sediment trapping occurred upstream of the vegetation barriers from the 1 st year onwards.Considering the depth of sediment trapped per experiment, the mean annual values reached 11.2 cm yr-1 after 3 years in experiment A, 7.7 cm yr-1 after 2–4 years in experiment C and 5.1 cm yr-1 after 5 years in experiment B. Occasionally, BLMs showed that they could trap up to 16 and 15 cm yr-1 in experiments A and C, respectively. Considering the volumes oftrapped sediment and the sustainability of sediment trapping are discussed, and rules for bioengineering strategies are proposed. 展开更多
关键词 Erosion Marly gully Vegetation barriers Ecological engineering SALIX
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Timing of syn-orogenic extension in the Western Alps revealed by calcite U-Pb and hematite(U-Th)/He dating
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作者 Antonin Bilau Yann Rolland +11 位作者 Stéphane Schwartz Cécile Gautheron Thierry Dumont Dorian Bienveignant Benjamin Brigaud Nicolas Godeau Abel Guihou Pierre Deschamps Xavier Mangenot Marianna Corre Rosella Pinna-Jamme Nathaniel Findling 《Geoscience Frontiers》 2025年第2期59-75,共17页
Understanding fault activity over time provides valuable insights for reconstructing the tectonic history of an orogen,assessing seismological risks and understanding mineralization processes.In the Western Alps,one o... Understanding fault activity over time provides valuable insights for reconstructing the tectonic history of an orogen,assessing seismological risks and understanding mineralization processes.In the Western Alps,one of the main controversies in existing tectonic models is the understanding of syn-orogenic extension.Seismological evidence shows widespread extensional deformation related to the reactivation of major lithospheric structures,such as the Penninic Frontal Thrust(PFT).However,the onset age and origin of extension are still debated due to the lack of suitable geochronological data.Fault hematite and calcite geochronology as well as clumped isotope data can be used to relate fluid regimes to fault activity.The analysis of calcite brecciae from extensional faults above the PFT shows that two distinct fluid regimes were present.The first regime,occurring before 2 Ma is associated with upwelling of deep fluids and is recorded by fault calcite at a temperature>110°C.The second fluid regime is characterized by a meteoric signature and temperatures around 36°C,representing crystallization since 2 Ma.This study presents a new model for the Miocene tectonic history of the Western Alps that combines(U-Th)/He and U-Pb geochronology on fault hematite(13.3±0.8 to<0.8 Ma)and calcite(5.3±0.6 Ma).Results demonstrate a progression of extensional fault activity from east to west,from the Middle Miocene(ca.13 Ma)to the Quaternary.The onset of extension in the inner part of the belt coincides with the development of the fold and thrust belt in the western Alpine foreland.Our new model proposes that extension occurs in the hanging wall of a large top-to-the-west thrust,known as the Alpine Frontal Thrust.This thrust,located to the west of the External Crystalline Massifs gives rise to their uplifting and extension at the rear. 展开更多
关键词 Western Alps Briançonnais zone Hematite(U-Th) He U-Pb calcite Clumped isotopes Syn-orogenic extension
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Functional central nervous system regeneration:Challenges from axons to circuits
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作者 Apolline Delaunay Mickael Le Boulc’h +1 位作者 Stephane Belin Homaira Nawabi 《Neural Regeneration Research》 2026年第5期1983-1984,共2页
The mature central nervous system(CNS,composed of the brain,spinal cord,olfactory and optic nerves)is unable to regenerate spontaneously after an insult,both in the cases of neurodegenerative diseases(for example Alzh... The mature central nervous system(CNS,composed of the brain,spinal cord,olfactory and optic nerves)is unable to regenerate spontaneously after an insult,both in the cases of neurodegenerative diseases(for example Alzheimer's or Parkinson's disease)or traumatic injuries(such as spinal cord lesions).In the last 20 years,the field has made significant progress in unlocking axon regrowth. 展开更多
关键词 parkinsons disease unlocking axon regrowth neurodegenerative diseases central nervous system cnscomposed functional regeneration axon regrowth spinal cord lesions central nervous system
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High-Repetition-Rate Attosecond Extreme Ultraviolet Beamlines at ELI ALPS for Studying Ultrafast Phenomena 被引量:1
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作者 Mojtaba Shirozhan Sudipta Mondal +24 位作者 Tímea Grósz Balázs Nagyillés Balázs Farkas Arjun Nayak Naveed Ahmed Indranuj Dey Shivani Choudhary De Marco Kwinten Nelissen Miklos Kiss Lénárd Gulyás Oldal Tamás Csizmadia Zoltán Filus Massimo De Marco Saibabu Madas Mousumi Upadhyay Kahaly Dimitris Charalambidis Paraskevas Tzallas Elisa Appi Robin Weissenbilder PEng-Johnsson Anne L’Huillier Zsolt Diveki Balázs Major Katalin Varjú Subhendu Kahaly 《Ultrafast Science》 2024年第6期1-27,共27页
Advancements in light engineering have led to the creation of pulsed laser sources capable of delivering high-repetition-rate,high-power few-cycle laser pulses across a wide spectral range,enabling exploration of many... Advancements in light engineering have led to the creation of pulsed laser sources capable of delivering high-repetition-rate,high-power few-cycle laser pulses across a wide spectral range,enabling exploration of many fascinating nonlinear processes occurring in all states of matter.High-harmonic generation,one such process,which converts the low-frequency photons of the driver laser field into soft x-rays,has revolutionized atomic,molecular,and optical physics,leading to progress in attosecond science and ultrafast optoelectronics.The Extreme Light Infrastructure,Attosecond Light Pulse Source(ELI ALPS)facility pioneers state-of-the-art tools for research in these areas.This paper outlines the design rationale,capabilities,and applications of plasma-and gas-based high-repetition-rate(1 kHz to 100 kHz)attosecond extreme ultraviolet(XUV)beamlines developed at ELI ALPS,highlighting their potential for advancing various research fields. 展开更多
关键词 extreme ultraviolet attosecond science ul eli alps light engineering BEAMLINES pulsed laser sources ATTOSECOND high repetition rate
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Comment on:liver venous deprivation(LVD)or associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)?A retrospective multicentric study 被引量:17
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作者 Edouard Girard Bertrand Trilling Mircea Chirica 《Hepatobiliary Surgery and Nutrition》 SCIE 2021年第5期675-677,共3页
We read with interest the recently published paper by Chebaro et al.(1).The authors compared liver venous deprivation(LVD)and associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)which are... We read with interest the recently published paper by Chebaro et al.(1).The authors compared liver venous deprivation(LVD)and associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)which are two novel techniques used to achieve increased hypertrophy of the future liver remnant(FLR)in view of extensive liver resections(2,3). 展开更多
关键词 LIVER DEPRIVATION
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法向扰动下裂隙砂岩的剪切力学性质与细观演化特征
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作者 张洁 冯国瑞 +5 位作者 郭军 文晓泽 冯文明 张旭 张亮 DIAS Daniel 《采矿与岩层控制工程学报》 北大核心 2025年第2期178-193,共16页
为探究裂隙岩体在扰动作用下的剪切力学行为和细观演化特征,开展了恒定作用下裂隙砂岩的直剪试验,采用PFC^(2D)建立了不同裂隙角度离散元模型,分析了法向恒定和扰动作用下试样的剪切强度和破坏特征;基于剪切过程中细观演化规律,揭示了... 为探究裂隙岩体在扰动作用下的剪切力学行为和细观演化特征,开展了恒定作用下裂隙砂岩的直剪试验,采用PFC^(2D)建立了不同裂隙角度离散元模型,分析了法向恒定和扰动作用下试样的剪切强度和破坏特征;基于剪切过程中细观演化规律,揭示了扰动作用下裂隙砂岩的裂纹扩展规律和能量耗散机理。研究结果表明:①预制裂隙使岩石剪切强度显著降低,两种加载模式下不同裂隙角度的剪切强度降幅分别为9.79%~20.28%和11.12%~16.78%;随着裂隙角度增加,应力–应变曲线斜率降低,剪切强度和峰值位移呈现出先增大后减小的趋势,具有明显的角度效应,剪切强度与裂隙角度成三次函数关系;法向扰动削弱了角度效应的影响,使岩石抵抗剪切变形的能力减弱,破坏提前。②在剪切过程中,岩石内部力链呈现出与荷载方向一致的演化趋势,微裂纹主要从试样两端和预制裂隙两端萌生和发育;微裂纹倾角主要分布在20°~80°,破坏后剪切裂纹占比为78%~81%,扰动作用使该过程中产生的各类裂纹增多,起裂位移减小,剪切裂纹占比增大。③AE振铃计数的发展可分为平静期、缓增期、爆发期和稳定期,扰动作用下“平静期”较短,且在“缓增期”呈现出阶梯性增长趋势。④扰动作用下的剪切试验,试样失效点的总能量较低;直至试样破坏,大部分输入能都以弹性应变能的形式储存在试样中,且在扰动作用下的弹性能显著低于恒定作用下的,降幅达到9.87%~13.94%;扰动使试样储能能力降低,耗散能增加,更容易产生裂纹从而破坏。 展开更多
关键词 裂隙岩体 法向扰动 剪切特性 细观演化 能量耗散
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怒江干流云南段泥石流时空分异特征、驱动因素及演化趋势分析
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作者 张佳佳 杨东旭 +7 位作者 高波 陈龙 李元灵 田尤 黄海 李洪梁 李金洋 李奕霖 《中国地质》 北大核心 2025年第6期2238-2255,共18页
【研究目的】怒江干流云南段是云南省境内泥石流灾害最为发育的区域之一,由于人地关系矛盾突出,历史泥石流事件已造成巨大的人员伤亡和财产损失,探究该区域泥石流的时空分异特征、驱动因素以及泥石流的未来演化趋势具有重要意义。【研... 【研究目的】怒江干流云南段是云南省境内泥石流灾害最为发育的区域之一,由于人地关系矛盾突出,历史泥石流事件已造成巨大的人员伤亡和财产损失,探究该区域泥石流的时空分异特征、驱动因素以及泥石流的未来演化趋势具有重要意义。【研究方法】基于资料搜集、遥感解译、现场调查、走访,获取较以往研究更为详实的野外一手资料,更新历史泥石流事件数据库。基于统计学方法分析泥石流的时空分异特征。利用地理探测器揭示泥石流的主控因素。【研究结果】(1)泥石流在空间上以泸水市上江镇为界表现出北强南弱的空间分异特征。时间上表现为年尺度总体增加,月尺度分异的特征;(2)泥石流南北空间分异的主控因子分别为气候条件、断裂构造、地形地貌,时间分异的主控因素为降雨和地震;(3)泥石流总体愈加活跃,自2000年以来表现出3年左右的活动周期,呈上升趋势的极端降雨、突发的强震均会引发泥石流的集中暴发。【结论】怒江干流云南段历史泥石流事件记录由原来的86次更新为134次,在此基础上得到的泥石流时空分异、驱动因素和未来演化趋势的研究成果将加深怒江干流云南段泥石流的研究深度,可为区内场镇、聚居区以及重要交通干线的泥石流灾害风险防御工作提供一定的技术支撑。 展开更多
关键词 时空分异 主控因素 发展趋势 泥石流 地质灾害调查工程 怒江干流云南段
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Deciphering the mechanobiology of microglia in traumatic brain injury with advanced microsystems 被引量:1
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作者 Anthony Procès Sylvain Gabriele 《Neural Regeneration Research》 SCIE CAS 2025年第8期2304-2306,共3页
Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results from a mechanical insult to the brain,leading to neuronal and axonal damage and subsequently causing a secondary injury.Withi... Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results from a mechanical insult to the brain,leading to neuronal and axonal damage and subsequently causing a secondary injury.Within minutes of TBI,a neuroinflammatory response is triggered,driven by intricate molecular and cellular inflammatory processes. 展开更多
关键词 TRAUMATIC INJURY DAMAGE
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Translational machinery and translation regulation in axon regeneration
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作者 Homaira Nawabi Stephane Belin 《Neural Regeneration Research》 SCIE CAS 2025年第5期1392-1394,共3页
Over the centuries,the regeneration field has been puzzled by the dual response of the central nervous system(CNS-brain,spinal cord,cranial nervesⅠandⅡ)and the peripheral nervous system(PNS that refers to all the ne... Over the centuries,the regeneration field has been puzzled by the dual response of the central nervous system(CNS-brain,spinal cord,cranial nervesⅠandⅡ)and the peripheral nervous system(PNS that refers to all the nerves that innervate muscles,skin,organs,bones among others).Even Ramon y Cajal had noticed that an injury to the PNS often leads to axon regrowth,in contrast to the CNS. 展开更多
关键词 NERVES ORGANS muscles
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A spotlight on dosage and subject selection for effective neuroprotection: exploring the central role of mitochondria
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作者 John Mitrofanis Jonathan Stone +3 位作者 Michael R.Hamblin Pierre Magistretti Alim-Louis Benabid Glen Jeffery 《Neural Regeneration Research》 SCIE CAS 2025年第4期1081-1082,共2页
Neurons are notoriously vulnerable cell types.Even the slightest change in their internal and/or external environments will cause much distress and dysfunction,leading often to their death.A range of pathological cond... Neurons are notoriously vulnerable cell types.Even the slightest change in their internal and/or external environments will cause much distress and dysfunction,leading often to their death.A range of pathological conditions,including stroke,head trauma,and neurodegenerative disease,can generate stress in neurons,affecting their survival and proper function.In most neural pathologies,mitochondria become dysfunctional and this plays a pivotal role in the process of cell death.The challenge over the last few decades has been to develop effective interventions that improve neuronal homeostasis under pathological conditions.Such interventions,often referred to as disease-modifying or neuroprotective,have,however,proved frustratingly elusive,at both preclinical and,in particular,clinical levels.In this perspective,we highlight two factors that we feel are key to the development of effective neuroprotective treatments.These are:firstly,the choice of dose of intervention and method of application,and secondly,the selection of subjects,whether they be patients or the animal model. 展开更多
关键词 protective DOSAGE DISTRESS
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The evolution process between the earthquake swarm beneath the Noto Peninsula,central Japan and the 2024 M 7.6 Noto Hanto earthquake sequence 被引量:1
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作者 Zhigang Peng Xinglin Lei +6 位作者 Qing-Yu Wang Dun Wang Phuc Mach Dongdong Yao Aitaro Kato Kazushige Obara Michel Campillo 《Earthquake Research Advances》 2025年第1期10-21,共12页
Several physical mechanisms of earthquake nucleation,such as pre-slip,cascade triggering,aseismic slip,and fluid-driven models,have been proposed.However,it is still not clear which model plays the most important role... Several physical mechanisms of earthquake nucleation,such as pre-slip,cascade triggering,aseismic slip,and fluid-driven models,have been proposed.However,it is still not clear which model plays the most important role in driving foreshocks and mainshock nucleation for given cases.In this study,we focus on the relationship between an intensive earthquake swarm that started beneath the Noto Peninsula in Central Japan since November 2020 and the nucleation of the 2024 M 7.6 Noto Hanto earthquake.We relocate earthquakes listed in the standard Japan Meteorological Agency(JMA)catalog since 2018 with the double-different relocation method.Relocated seismicity revealed that the 2024 M 7.6 mainshock likely ruptured a thrust fault above a parallel fault where the M 6.5 Suzu earthquake occurred in May 2023.We find possible along-strike and along-dip expansion of seismicity in the first few months at the beginning of the swarm sequence,while no obvious migration pattern in the last few days before the M 7.6 mainshock was observed.Several smaller events occurred in between the M 5.5 and M 4.6 foreshocks that occurred about 4min and 2 min before the M 7.6 mainshock.The Coulomb stress changes from the M 5.5 foreshock were negative at the hypocenter of the M 7.6 mainshock,which is inconsistent with a simple cascade triggering model.Moreover,an M 5.9 foreshock was identified in the JMA catalog 14 s before the mainshock.Results from backprojection of high-frequency teleseismic P waves show a prolonged initial rupture process near the mainshock hypocenter lasting for~25 s,before propagating bilaterally outward.Our results suggest a complex evolution process linking the earthquake swarm to the nucleation of the M 7.6 mainshock at a region of complex structures associated with the bend of a mapped large-scale reverse fault.A combination of fluid migration,aseismic slip and elastic stress triggering likely work in concert to drive both the prolonged earthquake swarm and the nucleation of the M 7.6 mainshock. 展开更多
关键词 EARTHQUAKE BENEATH EVOLUTION
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Brivaracetam and rufinamide combination increased seizure threshold and improved neurobehavioral deficits in corneal kindling model of epilepsy
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作者 Awais Sattar Zohabia Rehman +4 位作者 Hammad Murtaza Waseem Ashraf Tanveer Ahmad Faleh Alqahtani Imran Imran 《Animal Models and Experimental Medicine》 2025年第2期209-221,共13页
Background:Besides seizures,a myriad of overlapping neuropsychiatric and cognitive comorbidities occur in patients with epilepsy,which further debilitates their quality of life.This study provides an in-depth characte... Background:Besides seizures,a myriad of overlapping neuropsychiatric and cognitive comorbidities occur in patients with epilepsy,which further debilitates their quality of life.This study provides an in-depth characterization of the impact of brivaracetam and rufinamide individually and in combination at 10 and 20 mg/kg doses,respec-tively,on corneal kindling-induced generalized seizures and behavioral alterations.Furthermore,observed convulsive frequency and behavioral changes were corre-lated to post-kindling-induced changes in the activity of markers of oxidative stress.Methods:Adult C57BL/6 mice were kindled via twice-daily transcorneal 50-Hz elec-trical stimulations(3 mA)for 3 s for 12 days until animals reached a fully kindled state.After the kindling procedure,animals were tested using a set of behavioral tests,and neurochemical alterations were assessed.Results:Corneal-kindled animals exhibited intense generalized convulsions,altered behavioral phenotypes typified by positive symptoms(hyperlocomotion),negative symptoms(anxiety and anhedonia),and deficits in semantic and working memory.BRV 10+RFM 20 dual regime increased convulsive threshold and propensity toward the start of stage 4–5 seizures and improved phenotypical deficits,that is,anxiety,depression,and memory impairments.Moreover,this combination therapy mitigated kindling-induced redox impairments as evidenced by reduced malondialdehyde and acetylcholinesterase levels and increased glutathione antioxidant activity in the brain of animals subjected to repetitive brain insult.Conclusion:Based on our outcomes,this dual therapy provides supporting evidence in alleviating epilepsy-induced neurobehavioral comorbidities and changes in redox homeostasis. 展开更多
关键词 BRIVARACETAM corneal kindling EPILEPSY neurobehavioral analyses oxidative stress RUFINAMIDE
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Unraveling the neuroprotective effect of perampanel and lacosamide combination in the corneal kindling model for epilepsy in mice
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作者 Saba Tehreem Azka Sabir +4 位作者 Maryam Farooq Waseem Ashraf Faleh Alqahtani Tanveer Ahmad Imran Imran 《Animal Models and Experimental Medicine》 2025年第2期222-238,共17页
Background:Scientific evidence to guide clinicians on the use of different antiseizure drugs in combination therapy is either very limited or lacking.In this study,the impact of lacosamide and perampanel alone and in ... Background:Scientific evidence to guide clinicians on the use of different antiseizure drugs in combination therapy is either very limited or lacking.In this study,the impact of lacosamide and perampanel alone and in combination was tested in corneal kindling model in mice,which is a cost-effective mechanism for screening of antiseizure drugs.Methods:The impact of lacosamide(5 mg/kg)and perampanel(0.125 mg/kg)alone and their combination was tested in corneal kindling process(3-mA current for 3 s applied twice daily for consecutive 12 days)in male BALB/c mice.Post-kindling,mice were subjected to a battery of behavioral tests assessing anxiety,memory,and depression-like behaviors.Brain tissues were then harvested for analysis of oxidative stress biomarkers.Results:Our results showed that the combination therapy of lacosamide and perampanel was more effective in reducing seizure progression than monotherapy of these drugs.Animals treated with combination therapy showed significant behavioral improvements,as reduced anxiety and depression were noticed,and their cognitive abilities were notably better compared to animals of all other groups.Moreover,biochemical assays of isolated brains from combination-treated group revealed lesser amount of oxidative stress.In addition,outcomes of dual regime were comparable to the phenytoin in seizure control but showed superior benefits in mitigation of kindling-prompted behavioral dysfunction and oxidative stress.Conclusions:This study suggests that the lacosamide and perampanel combination therapy worked noticeably better in halting the corneal kindling process in mice and improved the epilepsy-associated psychiatric disorders that might be due to antioxidant effects of both drugs. 展开更多
关键词 behavioral studies corneal kindling LACOSAMIDE learned helplessness oxidative stress PERAMPANEL
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Tire particles of different sizes induce a proinflammatory response of varying intensity in lung cells
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作者 Abderrahmane Bouredji Bogdan Muresan-Paslaru +3 位作者 Riadh Lakhmi Raphaël Passas Jérémie Pourchez Valérie Forest 《Journal of Environmental Sciences》 2025年第12期586-597,共12页
Pollution from road traffic contributes significantly to air pollution through pollutants from exhaust emissions(gases and particles)and non-exhaust emissions(tire wear particles,brake wear particles and the resuspens... Pollution from road traffic contributes significantly to air pollution through pollutants from exhaust emissions(gases and particles)and non-exhaust emissions(tire wear particles,brake wear particles and the resuspension of road dust).This research examined the hazard of tire particles(TP)and in particular evaluated the effect of TP size on lung macrophages.TP were obtained by cryogenic grinding of a tire and subsequent sieving to obtain four groups of particles(TP70,TP30,TP15,TP5)of different sizes with average diameters of 107μm,55μm,22μm,and 6μm,respectively.A complete physicochemical characterization was performed to determine the size distribution,chemical composition and morphology of these particles.We then investigated the proinflammatory response,oxidative stress and cytotoxicity induced in RAW264.7 cells exposed to four different TP concentrations for 24 h.TP had no direct effect on cytotoxicity,nor did they increase reactive oxygen species(ROS)production in the cells.However,TP induced a significant and size-dependent proinflammatory effect,which was particularly pronounced with small particles.Moreover,this effect was concentration-dependent. 展开更多
关键词 Air pollution Traffic emissions Non-exhaust emissions Tire and Road Wear Particles(TRWP) Health effects Proinflammatory response
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Accessing Elastic Properties of Porous Solid Oxide Fuel Cell Electrodes Using 2D Image-Based Discrete Element Modeling and Deep Learning
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作者 Shihao Zhou Yan Zeng +6 位作者 Xuhao Liu Xianhang Li Christophe L.Martin Naoki Shikazono Shotaro Hara Zilin Yan Zheng Zhong 《Acta Mechanica Solida Sinica》 2025年第3期384-401,共18页
The mechanical properties of solid oxide fuel cells(SOFCs)can limit their mechanical stability and lifespan.Understanding the correlation between the microstructure and mechanical properties of porous electrode is ess... The mechanical properties of solid oxide fuel cells(SOFCs)can limit their mechanical stability and lifespan.Understanding the correlation between the microstructure and mechanical properties of porous electrode is essential for enhancing the performance and durability of SOFCs.Accurate prediction of mechanical properties of porous electrode can be achieved by microscale finite element modeling based on three-dimensional(3D)microstructures,which requires expensive 3D tomography techniques and massive computational resources.In this study,we proposed a cost-effective alternative approach to access the mechanical properties of porous electrodes,with the elastic properties of La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δc)athode serving as a case study.Firstly,a stochastic modeling was used to reconstruct 3D microstructures from two-dimensional(2D)cross-sections as an alternative to expensive tomography.Then,the discrete element method(DEM)was used to predict the elastic properties of porous ceramics based on the discretized 3D microstructures reconstructed by stochastic modeling.Based on 2D microstructure and the elastic properties calculated by the DEM modeling of the 3D reconstructed porous microstructures,a convolutional neural network(CNN)based deep learning model was built to predict the elastic properties rapidly from 2D microstructures.The proposed combined framework can be implemented with limited computational resources and provide a basis for rapid prediction of mechanical properties and parameter estimation for multiscale modeling of SOFCs. 展开更多
关键词 Porous ceramics MICROSTRUCTURE Stochastic reconstruction Discrete element method Deep learning
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Probabilistic Assessment of Constitutive Model Parameters:Insight from a Statistical Damage Constitutive Model and a Simple Critical State Hypoplastic Model
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作者 Yang Xue Fasheng Miao +3 位作者 Yiping Wu Linwei Li Daniel Dias Yang Tang 《Journal of Earth Science》 2025年第2期685-699,共15页
The constitutive model is essential for predicting the deformation and stability of rocksoil mass.The estimation of constitutive model parameters is a necessary and important task for the reliable characterization of ... The constitutive model is essential for predicting the deformation and stability of rocksoil mass.The estimation of constitutive model parameters is a necessary and important task for the reliable characterization of mechanical behaviors.However,constitutive model parameters cannot be evaluated accurately with a limited amount of test data,resulting in uncertainty in the prediction of stress-strain curves.This paper proposes a Bayesian analysis framework to address this issue.It combines the Bayesian updating with the structural reliability and adaptive conditional sampling methods to assess the equation parameter of constitutive models.Based on the triaxial and ring shear tests on shear zone soils from the Huangtupo landslide,a statistical damage constitutive model and a critical state hypoplastic constitutive model were used to demonstrate the effectiveness of the proposed framework.Moreover,the parameter uncertainty effects of the damage constitutive model on landslide stability were investigated.Results show that reasonable assessments of the constitutive model parameter can be well realized.The variability of stress-strain curves is strongly related to the model prediction performance.The estimation uncertainty of constitutive model parameters should not be ignored for the landslide stability calculation.Our study provides a reference for uncertainty analysis and parameter assessment of the constitutive model. 展开更多
关键词 probabilistic back analysis Bayesian approach model parameter estimation constitutive model landslide stability engineering geology
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Effort minimization:A permanent,dynamic,and surmountable influence on physical activity
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作者 Silvio Maltagliati Layan Fessler +7 位作者 Qian Yu Zhihao Zhang Yanxia Chen Olivier Dupuy Ryan SFalck Neville Owen Liye Zou Boris Cheval 《Journal of Sport and Health Science》 2025年第4期43-47,共5页
Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transit... Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transition from intention to action is challenging-a situation that has important public health implications. According to the World Health Organization,^(5)1 person dies every 6 s worldwide from causes related to physical inactivity, which underscores the urgency of addressing this situation. 展开更多
关键词 World Health Organization physical activity pa effort minimization intention action public health physical inactivity physical activity
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钾长石在碱性条件下的蚀变机制及其蚀变产物托贝莫来石的纳米结构研究 被引量:6
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作者 翟媛媛 曾庆栋 +3 位作者 HELLMANN Roland 刘善科 刘建明 南景博 《岩石学报》 SCIE EI CAS CSCD 北大核心 2020年第9期2834-2844,共11页
钾长石在碱性流体蚀变过程中会形成层状铝硅酸盐等矿物,前人对其反应机制和反应产物进行了研究,但缺乏微观尺度尤其是纳米尺度的探讨。因此,作者对钾长石在极端碱性条件下(190℃,24h,初始p H=12.4)的蚀变机制及其蚀变产物层状硅酸盐托... 钾长石在碱性流体蚀变过程中会形成层状铝硅酸盐等矿物,前人对其反应机制和反应产物进行了研究,但缺乏微观尺度尤其是纳米尺度的探讨。因此,作者对钾长石在极端碱性条件下(190℃,24h,初始p H=12.4)的蚀变机制及其蚀变产物层状硅酸盐托贝莫来石的显微结构开展了纳米尺度的研究。X射线粉末衍射、扫描电子显微镜、能量色散光谱等观测结果显示,钾长石在碱性条件下水热蚀变所得到的产物主要为托贝莫来石、水钙铝榴石和方解石。高分辨率的透射电镜结果表明,在钾长石与次生矿物相的界面形成了纳米级的多孔非晶质层,且在空间上表现出结构的不连续性。界面溶解-再沉淀(CIDR)机制很好地解释了钾长石与次生矿物相界面的空间不连续性和非晶质层的形成。对蚀变产物中纤维状的托贝莫来石晶体进行显微结构表征,结果表明托贝莫来石的孔隙直径为0~160nm,平均孔径约为40nm;其构成的纳米孔隙和通道有利于增加周围流体中离子和气体的溶解度,并可能会影响局部化学平衡。这为层状铝硅酸盐作为自然界以及工业吸附材料和催化剂的更广泛应用提供了重要依据。 展开更多
关键词 钾长石 界面溶解-再沉淀 非晶质层 托贝莫来石 纳米孔隙
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场地分类研究现状及有关问题的讨论 被引量:7
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作者 薄景山 李琪 +2 位作者 孙强强 彭达 李孝波 《自然灾害学报》 CSCD 北大核心 2021年第3期1-13,共13页
强震观测资料和震害资料表明,场地条件对地震动有着重要的影响。从工程抗震的角度出发,依据场地条件对场地进行分类并规定不同场地的设计地震动参数是目前各国抗震设计规范的通行做法,也是当前岩土工程抗震研究的重要内容。本文对国内... 强震观测资料和震害资料表明,场地条件对地震动有着重要的影响。从工程抗震的角度出发,依据场地条件对场地进行分类并规定不同场地的设计地震动参数是目前各国抗震设计规范的通行做法,也是当前岩土工程抗震研究的重要内容。本文对国内外抗震规范中场地分类的研究历程进行了梳理和总结;对场地分类指标进行了分析和评述,并对有代表性的中国、美国、欧洲、日本、土耳其、智利、尼泊尔、伊朗、韩国、澳大利亚和新西兰等国家和地区抗震设计规范中的场地分类方案开展了对比研究。在此基础上,重点讨论了我国现行抗震设计规范中场地分类存在的问题,并提出了这一领域今后需要研究的若干关键问题。本文的工作对从事场地分类研究的科技人员有一定的参考价值。 展开更多
关键词 场地分类 分类指标 分类方案 研究现状 对比研究
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干细胞外泌体在老年肿瘤治疗中的研究进展 被引量:1
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作者 王媛媛 丁宇 +5 位作者 Tham SengKong 冷芬 毛娟 朱玲 丁克祥 戴萌 《国际老年医学杂志》 2021年第2期114-119,共6页
老年肿瘤恶性程度高、转移速度快,且并发症和恶病质多见,特别是合并多种慢性疾病,临床治疗具有很大难度。目前,对老年肿瘤大多数采用姑息治疗、保守治疗、消极治疗、甚至放弃治疗,使患者错过了最佳治疗期。干细胞外泌体可以传递和运载... 老年肿瘤恶性程度高、转移速度快,且并发症和恶病质多见,特别是合并多种慢性疾病,临床治疗具有很大难度。目前,对老年肿瘤大多数采用姑息治疗、保守治疗、消极治疗、甚至放弃治疗,使患者错过了最佳治疗期。干细胞外泌体可以传递和运载某些治疗性核酸、蛋白和靶向药物等抗癌药物或制剂,是较为理想的肿瘤药物传递载体,且可选择性地结合肿瘤内皮细胞传递到癌组织。另外在某些方面,间充质干细胞对肿瘤生长有不同的作用,包括改变肿瘤细胞生长微环境、调控肿瘤细胞某些生物信息和遗传特性、抑制已形成肿瘤的进展、明显减少在治疗过程中对其他正常组织的副作用。不过,干细胞外泌体用于肿瘤临床治疗的应用研究仍处于基础医学与临床应用研究阶段。随着对干细胞外泌体的深入研究,其在未来可能对于肿瘤干细胞治疗、药物递送等领域发挥重要作用。 展开更多
关键词 干细胞 外泌体 老年肿瘤 治疗 研究进展
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