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Qualitative Evaluation of Academic Researchers in Computer Science:Practices and Reflections from CNRS
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作者 Pierre Senellart 《计算机教育》 2025年第12期36-41,共6页
The evaluation of academic researchers often relies on quantitative metrics,despite their limitations.This paper examines the qualitative assessment approach used by the French National Center for Scientific Research(... The evaluation of academic researchers often relies on quantitative metrics,despite their limitations.This paper examines the qualitative assessment approach used by the French National Center for Scientific Research(CNRS)in Computer Science(Section 6),as presented by a National Committee for Scientific Research(CoNRS)committee president.Rejecting bibliometrics like impact factors,CNRS emphasizes in-depth peer review of research quality,diverse outputs(e.g.,software and datasets),and field-specific considerations.The process,aligned with the San Francisco Declaration on Research Assessment(DORA),faces challenges in scalability and subjectivity,addressed through committee diversity and structured deliberation.This work provides insights for institutions seeking fairer,more holistic research evaluation frameworks. 展开更多
关键词 Research evaluation Qualitative assessment CNRS DORA Computer science
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Beyond paralysis:Impact of spinal cord injury on brain inflammation and cognitive function through cell therapy
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作者 Quentin Delarue Nicolas Guérout 《Neural Regeneration Research》 2026年第6期2347-2348,共2页
Traumatic spinal cord injury(SCI)is a pathological condition that impairs both sensorimotor and cognitive functions.While research has long focused on understanding the pathophysiology of SCI and developing treatments... Traumatic spinal cord injury(SCI)is a pathological condition that impairs both sensorimotor and cognitive functions.While research has long focused on understanding the pathophysiology of SCI and developing treatments,only a few studies have investigated the cellular and molecular consequences that occur in the brain after trauma.From the earliest stages,the injury triggers microglial activation,increased neuronal death,and reduced hippocampal neurogenesis in the dentate gyrus. 展开更多
关键词 reduced hippocampal neurogenesis celltherapy dentate gyrus cognitivefunction braininflammation cellular molecular consequences spinalcordinjury traumatic spinal cord injury sci
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Magnetic pulse welding of Al-5754 with Al-7075 and MARS 380:Weldability windows and ballistic testing
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作者 Benoit Lagain Thomas Heuzé +1 位作者 Guillaume Racineux Michel Arrigoni 《Defence Technology(防务技术)》 2026年第1期64-79,共16页
Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining... Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining technique that overcomes these issues by using impact to create strong bonds without melting the substrate materials.This study investigates the weldability of aluminum alloy Al-5754 with Al-7075 and MARS 380 steel,used in armouring solutions of defense systems,by the use of MPW.In this work,weldability windows are investigated by varying standoff distances between the coating material and its substrate(0.25-4.5 mm)and discharge energies(5-13 kJ)with both O-shape and U-shape inductors.Mechanical strength of the welded joints were assessed through single lap shear tests,identifying optimal welding parameters.Then,the velocity profiles of the flyer plates were measured using heterodyne velocimetry to understand the dynamics of the impact.Then,substructures assembled with the optimal welding conditions were subjected to ballistic testing using 7.62 mm×51 mm NATO and 9 mm×19 mm Parabellum munitions to evaluate the resilience of the welds under ballistic impact.The outcomes demonstrate that MPW effectively joins Al-5754 with both Al-7075 and MARS 380,producing robust welds capable of withstanding ballistic impacts under certain conditions.This research advances the application of MPW in lightweight ballistic protection of defense systems,contributing to the development of more resilient and lighter protective structures. 展开更多
关键词 Magnetic pulse welding(MPW) Dissimilar material joining Weldability windows Impact welding Ballistic testing
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p21 as an essential regulator of neurogenic homeostasis in neuropathological conditions
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作者 Valentina Mastrorilli Stefano Farioli-Vecchioli 《Neural Regeneration Research》 2026年第2期675-676,共2页
Adult neurogenesis is a highly dynamic process that leads to the production of new neurons from a population of quiescent neural stem cells(NSCs).In response to specific endogenous and/or external stimuli,NSCs enter a... Adult neurogenesis is a highly dynamic process that leads to the production of new neurons from a population of quiescent neural stem cells(NSCs).In response to specific endogenous and/or external stimuli,NSCs enter a state of mitotic activation,initiating proliferation and differentiation pathways.Throughout this process,NSCs give rise to neural progenitors,which undergo multiple replicative and differentiative steps,each governed by precise molecular pathways that coordinate cellular changes and signals from the surrounding neurogenic niche. 展开更多
关键词 adult neurogenesis quiescent neural stem cells nscs precise molecular pathways mitotic activationinitiating cellular changes neurogenic homeostasis neural progenitorswhich production new neurons
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Mitochondria-derived vesicles:New players in the game of neurodegeneration
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作者 Laura Palumbo Domenico Nuzzo +1 位作者 Antonella Girgenti Pasquale Picone 《Neural Regeneration Research》 2026年第2期679-680,共2页
Introduction:One of the main events that regulate a cell’s well-being is cell-to-cell communication.This intercellular mechanism of information transfer is often mediated by vesicular trafficking.Mitochondrial-derive... Introduction:One of the main events that regulate a cell’s well-being is cell-to-cell communication.This intercellular mechanism of information transfer is often mediated by vesicular trafficking.Mitochondrial-derived vesicles(MDVs)are an emerging subpopulation of extracellular vesicle(EV)first discovered in 2008 that allow mitochondria to communicate with their surroundings. 展开更多
关键词 extracellular vesicles cell cell communication vesicular traffickingmitochondrial derived NEURODEGENERATION mitochondria derived vesicles vesicular trafficking extracellular vesicle ev first
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Extra-pineal melatonin in perisynaptic Schwann cell–muscle fiber cross talk at the regenerating neuromuscular junction
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作者 Samuele Negro Cesare Montecucco Michela Rigoni 《Neural Regeneration Research》 2026年第1期300-301,共2页
The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore functio... The neuromuscular junction and its proregenerative niche:The mammalian peripheral nervous system,unlike the central nervous system,has preserved throughout evolution the ability to regenerate and fully restore function.Key factors for effective nerve regeneration include a supportive neuronal environment and a coordinated tissue response(Brosius Lutz and Barres,2014). 展开更多
关键词 FUNCTION SYSTEM COORDINATED
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Tellurium-Terminated MXene Synthesis via One-Step Tellurium Etching
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作者 Guoliang Ma Zongbin Luo +3 位作者 Hui Shao Yanbin Shen Zifeng Lin Patrice Simon 《Nano-Micro Letters》 2026年第1期738-749,共12页
With the rapid development of twodimensional MXene materials,numerous preparation strategies have been proposed to enhance synthesis efficiency,mitigate environmental impact,and enable scalability for large-scale prod... With the rapid development of twodimensional MXene materials,numerous preparation strategies have been proposed to enhance synthesis efficiency,mitigate environmental impact,and enable scalability for large-scale production.The compound etching approach,which relies on cationic oxidation of the A element of MAX phase precursors while anions typically adsorb onto MXene surfaces as functional groups,remains the main prevalent strategy.By contrast,synthesis methodologies utilizing elemental etching agents have been rarely reported.Here,we report a new elemental tellurium(Te)-based etching strategy for the preparation of MXene materials with tunable surface chemistry.By selectively removing the A-site element in MAX phases using Te,our approach avoids the use of toxic fluoride reagents and achieves tellurium-terminated surface groups that significantly enhance sodium storage performance.Experimental results show that Te-etched MXene delivers substantially higher capacities(exceeding 50%improvement over conventionally etched MXene)with superior rate capability,retaining high capacity at large current densities and demonstrating over 90%capacity retention after 1000 cycles.This innovative synthetic strategy provides new insight into controllable MXene preparation and performance optimization,while the as-obtained materials hold promises for high-performance sodium-ion batteries and other energy storage systems. 展开更多
关键词 Te-terminated MXene Elemental tellurium etching Sodium-ion storage High-rate performance
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Empowering the NSC-34 cell line as a motor neuron model: Cytosine arabinoside's action
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作者 Giuseppe Vitale Susanna Amadio +1 位作者 Francesco Liguori Cinzia Volonté 《Neural Regeneration Research》 2026年第1期357-364,共8页
The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble dif... The NSC-34 cell line is a widely recognized motor neuron model and various neuronal differentiation protocols have been exploited. Under previously reported experimental conditions, only part of the cells resemble differentiated neurons;however, they do not exhibit extensive and time-prolonged neuritogenesis, and maintain their duplication capacity in culture. The aim of the present work was to facilitate long-term and more homogeneous neuronal differentiation in motor neuron–like NSC-34 cells. We found that the antimitotic drug cytosine arabinoside promoted robust and persistent neuronal differentiation in the entire cell population. Long and interconnecting neuronal processes with abundant growth cones were homogeneously induced and were durable for up to at least 6 weeks in culture. Moreover, cytosine arabinoside was permissive, dispensable, and mostly irreversible in priming NSC-34 cells for neurite initiation and regeneration after mechanical dislodgement. Finally, the expression of the cell proliferation antigen Ki67 was inhibited by cytosine arabinoside, whereas the expression levels of neuronal growth associated protein 43, vimentin, and motor neuron–specific p75, Islet2, homeobox 9 markers were upregulated, as confirmed by western blot and/or confocal immunofluorescence analysis. Overall, these findings support the use of NSC-34 cells as a motor neuron model for properly investigating neurodegenerative mechanisms and prospectively identifying neuroprotective strategies. 展开更多
关键词 cytosine arabinoside Islet2 Hb9 Ki67 mitosis inhibition neurite initiation neurite regeneration neuronal differentiation protocol NSC-34 P75
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Heat flow as a catalyst for radiogenic helium release in the East Africa Rift System
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作者 Ernest Mulaya Jon Gluyas +2 位作者 Ken McCaff rey David Byrne Chris Ballentine 《Acta Geochimica》 2026年第1期65-85,共21页
The Rukwa Rift section of the East Africa Rift System presents a type setting for radiogenic helium accumulation in a petroleum free basin.As a prerequisite for accumulation,a considerable high heat flow anomaly is re... The Rukwa Rift section of the East Africa Rift System presents a type setting for radiogenic helium accumulation in a petroleum free basin.As a prerequisite for accumulation,a considerable high heat flow anomaly is required from tectonothermal events to drive the release and circulation of radiogenic helium in the continental crust.Here we apply statistical analysis on geochemical data observed in thermal springs and recorded heat flow to account for crustal helium mass balance for each tectonothermal event in the region.Our results demonstrate anomalously high heat flow~64-99 mW/m^(2) with a consistent trend of helium isotopic ratio and fluid chemistry in the Rukwa Rift.Mass balance calculation show that the whole crustal volume underlying the East Africa Helium Pool(EAHP)has a capability of producing radiogenic helium of about 9.9×10^(6) mol/yr(22×10^(-6) mol 4He/m^(2) yr)while the total radiogenic helium flux ranges between~2.39×10^(6) mol/yr and~2.68×10^(9) mol/yr.The Tanzania Craton contributes largely to radiogenic helium releasing up to 50% of the total capacity in the region.The total ^(4)He emission in the Rukwa Rift Basin is about 4.45×10^(5)-5.01×10^(8) mol/yr which is thus equivalent to 19%-21% of the total production capacity in the region.These results imply that the helium accumulation in the EAHP would have started as early as Paleoproterozoic(2.349 Ga).These results provide a qualitative and quantitative insight to assess both helium and geothermal potentiality in the region. 展开更多
关键词 Radiogenic helium Rukwa Rift Heat flow Helium potential Helium concentration
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Learning-Based Prediction of Soft-Tissue Motion for Latency Compensation in Teleoperation
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作者 Guangyu Xu Yuxin Liu +4 位作者 Bo Yang Siyu Lu Chao Liu Junmin Lyu Wenfeng Zheng 《Computer Modeling in Engineering & Sciences》 2026年第1期1051-1074,共24页
Soft-tissue motion introduces significant challenges in robotic teleoperation,especially in medical scenarios where precise target tracking is critical.Latency across sensing,computation,and actuation chains leads to ... Soft-tissue motion introduces significant challenges in robotic teleoperation,especially in medical scenarios where precise target tracking is critical.Latency across sensing,computation,and actuation chains leads to degraded tracking performance,particularly around high-acceleration segments and trajectory inflection points.This study investigates machine learning-based predictive compensation for latency mitigation in soft-tissue tracking.Three models—autoregressive(AR),long short-term memory(LSTM),and temporal convolutional network(TCN)—were implemented and evaluated on both synthetic and real datasets.By aligning the prediction horizon with the end-to-end system delay,we demonstrate that prediction-based compensation significantly reduces tracking errors.Among the models,TCN achieved superior robustness and accuracy on complex motion patterns,particularly in multi-step prediction tasks,and exhibited better latency–horizon compatibility.The results suggest that TCN is a promising candidate for real-time latency compensation in teleoperated robotic systems involving dynamic soft-tissue interaction. 展开更多
关键词 Medical robotics TELEOPERATION soft tissue tracking motion prediction real-time control
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Modeling Alzheimer’s disease through the integration of exposome,inflammasome,and connectome
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作者 Lorenzo Pini Bruno P.Imbimbo Manuela Allegra 《Neural Regeneration Research》 2026年第6期2359-2360,共2页
Over a century ago,the first clinical and neuropathological insights into major neurodegenerative diseases began to emerge:the description of Alzheimer’s disease(AD)by Alois Alzheimer in 1906,frontotemporal dementia ... Over a century ago,the first clinical and neuropathological insights into major neurodegenerative diseases began to emerge:the description of Alzheimer’s disease(AD)by Alois Alzheimer in 1906,frontotemporal dementia by Arnold Pick in the same years,and Lewy bodies by Friedrich Lewy in 1912.These foundational studies laid the groundwork for the classification of what we now recognize as distinct neurodegenerative entities(Allali,2024). 展开更多
关键词 major neurodegenerative diseases clinical neuropathological insights lewy bodies INFLAMMASOME exposome CONNECTOME neurodegenerative diseases distinct neurodegenerative entities allali
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Advancing living Bacillus spore identification:Multi-head self-attention mechanism-enabled deep learning combined with single-cell Raman spectroscopy
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作者 Mengjiao Xue Fusheng Du +5 位作者 Lin He Junhui Hu Yuanpeng Li Yuan Lu Shuwen Zeng Yufeng Yuan 《Journal of Innovative Optical Health Sciences》 2026年第1期139-155,共17页
Many spore-forming Bacillus species can cause serious human diseases,because of accidental Bacillusspore infection.Thus,developing an identification strategy with both high sensitivity and specificity is greatly in de... Many spore-forming Bacillus species can cause serious human diseases,because of accidental Bacillusspore infection.Thus,developing an identification strategy with both high sensitivity and specificity is greatly in demand.In this work,we proposed a novel approach named multi-head self-attention mechanism-guided neural network Raman platform to identify living Bacillus spores within a single-cell resolution.The multi-head self-attention mechanism-guided neural network Raman platform was created by combining single-cell Raman spectroscopy,convolutional neural network(CNN),and multi-head self-attention mechanism.To address the limited size of the original spectra dataset,Gaussian noise-based spectra augmentation was employed to increase the number of single-cell Raman spectra datasets for CNN training.Owing to the assistance of both spectra augmentation and multi-head self-attention mechanism,the obtained prediction accuracy of five Bacillus spore species was further improved from 92.29±0.82%to 99.43±0.15%.To figure out the spectra differences covered by the multi-head self-attention mechanism-guided CNN,the relative classification weight from typical Raman bands was visualized via multi-head self-attention mechanism curve.In the process of spectra augmentation from 0 to 1000,the distribution of relative classification weight varied from a discrete state to a more concentrated phase.More importantly,these highlighted four Raman bands(1017,1449,1576,and 1660 cm^(-1))were assigned large weights,showing that the spectra differences in the Raman bands produced the largest contribution to prediction accuracy.It can be foreseen that,our proposed sorting platform has great potential in accurately identifying Bacillus and its related genera species at a single-cell level. 展开更多
关键词 Multi-head self-attention mechanism CNN single-cell Raman spectroscopy spectra augmentation advanced Bacillus spore identification
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Tracing equatorward and poleward boundaries of the magnetospheric cusp from a simulated X-ray image
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作者 Xue Wang TianRan Sun +4 位作者 C.Philippe Escoubet Andy Read YiHong Guo Steve Sembay Chi Wang 《Earth and Planetary Physics》 2026年第1期144-155,共12页
A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-d... A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-dimensional cusp boundary from a two-dimensional X-ray image because the detected X-ray signals will be integrated along the line of sight.In this work,a global magnetohydrodynamic code was used to simulate the X-ray images and photon count images,assuming an interplanetary magnetic field with a pure Bz component.The assumption of an elliptic cusp boundary at a given altitude was used to trace the equatorward and poleward boundaries of the cusp from a simulated X-ray image.The average discrepancy was less than 0.1 RE.To reduce the influence of instrument effects and cosmic X-ray backgrounds,image denoising was considered before applying the method above to SXI photon count images.The cusp boundaries were reasonably reconstructed from the noisy X-ray image. 展开更多
关键词 SMILE mission X-ray image cusp boundary
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Siphon-Based Divide-and-Conquer Policy for Enforcing Liveness on Petri Net Models of FMS Suffering from Deadlocks or Livelocks
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作者 Murat Uzam Bernard Berthomieu +3 位作者 Wei Wei Yufeng Chen Mohammed El-Meligy Mohamed Abdel Fattah Sharaf 《Computers, Materials & Continua》 2026年第1期580-609,共30页
A novel siphon-based divide-and-conquer(SbDaC)policy is presented in this paper for the synthesis of Petri net(PN)based liveness-enforcing supervisors(LES)for flexible manufacturing systems(FMS)prone to deadlocks or l... A novel siphon-based divide-and-conquer(SbDaC)policy is presented in this paper for the synthesis of Petri net(PN)based liveness-enforcing supervisors(LES)for flexible manufacturing systems(FMS)prone to deadlocks or livelocks.The proposed method takes an uncontrolled and bounded PN model(UPNM)of the FMS.Firstly,the reduced PNM(RPNM)is obtained from the UPNM by using PN reduction rules to reduce the computation burden.Then,the set of strict minimal siphons(SMSs)of the RPNM is computed.Next,the complementary set of SMSs is computed from the set of SMSs.By the union of these two sets,the superset of SMSs is computed.Finally,the set of subnets of the RPNM is obtained by applying the PN reduction rules to the superset of SMSs.All these subnets suffer from deadlocks.These subnets are then ordered from the smallest one to the largest one based on a criterion.To enforce liveness on these subnets,a set of control places(CPs)is computed starting from the smallest subnet to the largest one.Once all subnets are live,this process provides the LES,consisting of a set of CPs to be used for the UPNM.The live controlled PN model(CPNM)is constructed by merging the LES with the UPNM.The SbDaC policy is applicable to all classes of PNs related to FMS prone to deadlocks or livelocks.Several FMS examples are considered from the literature to highlight the applicability of the SbDaC policy.In particular,three examples are utilized to emphasize the importance,applicability and effectiveness of the SbDaC policy to realistic FMS with very large state spaces. 展开更多
关键词 Petri nets flexible manufacturing systems DEADLOCK livelock liveness-enforcing supervisor
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Exercise training-induced extracellular miR-136-3p modulates glucose uptake and myogenesis through targeting of NRDC in human skeletal muscle
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作者 Mutsumi Katayama Elena Caria +8 位作者 Dimitri Van Simaeys Anna Yagüe Sanz Romain Barrès Kenneth Caidahl Oscar P.B.Wiklander Samir El Andaloussi Per-Olof Berggren Juleen R.Zierath Anna Krook 《Journal of Sport and Health Science》 2026年第1期40-55,共16页
Background Regular physical training induces adaptive effects across multiple organ systems,highlighting the existence of inter-organ communication networks.However,the molecular mechanisms underlying both exercise-in... Background Regular physical training induces adaptive effects across multiple organ systems,highlighting the existence of inter-organ communication networks.However,the molecular mechanisms underlying both exercise-induced adaptations and organ-to-organ signaling are not fully characterized.Circulating extracellular vesicles(EVs),including exosomes,carry molecules like microRNAs(miRNAs)that may mediate tissue crosstalk.This study aimed to identify specific exercise training-responsive miRNAs that affect skeletal muscle function.Methods miRNA expression profiles of serum-derived EVs were analyzed in healthy young individuals before and after 3 weeks endurance exercise training.Exercise training-responsive miRNAs were then validated for a functional role in cellular metabolic processes in human myotubes.Results We identified several exercise training-responsive miRNAs within exosome-rich EVs in serum,including miR-136-3p.In human myotubes,miR-136-3p enhanced glucose uptake and targeted the nardilysin convertase(NRDC)gene.Transfection of miR-136-3p or silencing of NRDC induced a shift towards glycolytic metabolism in mitochondria and modulated gene expressions related to myogenesis.Pancreatic islets were identified as a potential source of miR-136-3p based on in silico analysis of gene expression and a molecular analysis of conditioned media from isolated pancreatic islets.Conclusion MiR-136-3p is an endurance training-responsive molecular transducer that modulates glucose metabolism and cellular proliferation in myocytes.Associated with EVs,extracellular miR-136-3p may serve as a molecular messenger to communicate islet–skeletal muscle crosstalk after exercise.Extracellular miR-136-3p may serve as a molecular messenger to communicate islet–skeletal muscle crosstalk.Our results highlight a miRNA-mediated mechanism that participates in inter-organ communication to fine tune the metabolic adaptations to exercise. 展开更多
关键词 Extracellular miRNA Endurance training Human skeletal muscle miR-136-3p Nardilycin convertase(NRDC)
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Correction:Flux‑based assessment of ozone visible foliar injury in Southern Alps
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作者 Elena Marra Alessandra De Marco +8 位作者 Andrea Ebone Anna Maria Ferrara Fabio Giannetti Francesco Tagliaferro Pierre Sicard Andrei Popa Ionel Popa Elena Paoletti Yasutomo Hoshika 《Journal of Forestry Research》 2026年第2期305-305,共1页
Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article ha... Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article has been corrected. 展开更多
关键词 visible foliar injury southern Alps flux based assessment yasutomo hoshika journal forestry research yasutoma hoshikathe OZONE
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Flux-based assessment of ozone visible foliar injury in Southern Alps
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作者 Elena Marra Alessandra De Marco +8 位作者 Andrea Ebone Anna Maria Ferrara Fabio Giannetti Francesco Tagliaferro Pierre Sicard Andrei Popa Ionel Popa Elena Paoletti Yasutomo Hoshika 《Journal of Forestry Research》 2026年第2期31-43,共13页
Tropospheric ozone(O_(3))is a harmful air pollutant negatively impacting forest health,causing O_(3)-specific visible foliar injury(O_(3)VFI).Ozone monitoring in forests has usually implemented by passive samplers,alt... Tropospheric ozone(O_(3))is a harmful air pollutant negatively impacting forest health,causing O_(3)-specific visible foliar injury(O_(3)VFI).Ozone monitoring in forests has usually implemented by passive samplers,although they cannot detect the diurnal peak when a significant part of stomatal O_(3)uptake occurs.This results into uncertainties for the calculation of stomatal O_(3)uptake.This study compares the stomatal-flux-based POD1(phytotoxic ozone dose above a threshold of 1 nmol m^(-2)s^(-1))for forest trees/shrubs estimated from data collected by either passive samplers or active O_(3)monitors to evaluate O_(3)damage to plants in terms of O_(3)VFI in the Southern Alps.The study was conducted over two years(2018-2019)in a mountainous Alpine area(Valle Stura,Italy).An integrative monitoring station for active O_(3)monitoring,as well as passive O_(3)monitors,were installed in an open field area(OFD).The O_(3)VFI was investigated in woody species in the light exposed sampling Site(LESS—Betula pendula,Fagus sylvatica,Larix decidua,Populus tremula,Salix caprea,Rubus sp.and Vaccinium myrtillus)in late summer according to the international co-operative programme on assessment and monitoring of air pollution effects on forests(ICP Forests)manual.The results confirmed that Fagus sylvatica and Rubus sp.are O_(3)-sensitive species showing relatively high POD1(>20 mmol m-2),while Larix decidua is O_(3)-tolerant.We derived flux-based critical levels(CL)corresponding to the presence of O_(3)VFI(5,25,and 50%of symptomatic plants along the LESS)from flux-effect relationships for forest protection against O_(3)VFI.The results support the hypothesis that passive samplers cannot detect episodic high stomatal O₃fluxes(>1 nmol m^(-2)s^(-1)).According to the active monitoring,the CL for O_(3)VFI occurrence was estimated to be 17.1 mmol m-2 POD1 for 25%presence and 34.3 mmol m-2 POD1 for 50%presence of symptomatic plants,while passive samplers underestimated POD1 values for CL calculations by 17%on average,with underestimation increasing at higher CL thresholds.The findings demonstrate that active monitoring refines CLs towards a proper quantitative assessment of O_(3)impact,particularly in capturing peak flux events that are crucial for evaluating plant damage and emphasizes the importance of active O₃monitoring for reliable forest health assessments. 展开更多
关键词 Stomatal conductance model Leaf symptoms FOREST Phytotoxic ozone dose
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Paralinearization of the Dirichlet-Neumann operator and applications to progressive gravity waves Dedicated to the NSFC-CNRS Chinese-French summer institute on fluid mechanics in 2010
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作者 ALAZARD Thomas 《Science China Mathematics》 SCIE 2012年第1期207-220,共14页
This note presents a paradifferential approach to the analysis of the water waves equations.
关键词 incompressible Euler equation free surface paradifferential calculus
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Shallow water equations for power law and Bingham fluids Dedicated to the NSFC-CNRS Chinese-French summer institute on fluid mechanics in 2010
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作者 FERNANDEZ-NIETO Enrique D. NOBLE Pascal VILA Jean-Paul 《Science China Mathematics》 SCIE 2012年第1期277-283,共7页
In this note, we provide a consistant thin layer theory for power law and Bingham incompressible fluids flowing down an inclined plane under the effect of gravity. The derivation of such equations is based on formal a... In this note, we provide a consistant thin layer theory for power law and Bingham incompressible fluids flowing down an inclined plane under the effect of gravity. The derivation of such equations is based on formal asymptotic expansions of solutions of Cauchy momentum equations in the shallow water scaling and in the neighbourhood of steady solutions so that we can close the average equations on the fluid height h and the total discharge rate q. 展开更多
关键词 shallow water equations asymptotic analysis non-Newtonian fluids
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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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