In EUV and X- ray regions, multilayer mirrors are the essential and necessary optics elements. The good prospects of the EUV and X- rays for next generation lithography system, microscopy in the “water windows”, ast...In EUV and X- ray regions, multilayer mirrors are the essential and necessary optics elements. The good prospects of the EUV and X- rays for next generation lithography system, microscopy in the “water windows”, astro- nomical telescope, spectroscopy, plasma diagnostics, and X- ray laser have impelled the development of multilayer optics. The paper introduces the recent results of the multilayer optics elements in Tongji University, including beam splitters, broadband/angular polarizers, supermirrors and high- reflectance mirrors. The product of reflectivity and transmissivity is above 4% for the Mo/Si multilayer beam splitter. Over the 15￣17 nm wavelength range, the s- re- flectivity of the non- periodic Mo/Si broadband multilayer polarizers is reasonably constant, as high as 36.6%, and the degree of polarization is more than 97.8%. At the fixed energy of 8 keV (Cu Kαline), the W/Si supermirror has the reflectivity of above 30% in the angle range of 0.4°￣0.85°, and a W/B4C supermirror has the reflectivity of about 20% in the angle range of 0.9°￣1.2°, and the reflectivity of W/C supermirror working in the grazing incident angle range of 0.9°￣1.2°is about 20%. The experimental results of some high- reflectance mirrors in our lab are also pre- sented, such as Mo/Si, Mo/Y, Cr/C, La/B4C, Si/C and Si/SiC. The reflectivity of Mo/Si multilayer is as high as 61.1% at wavelength of 13.4 nm.展开更多
Background:Academic stress is a critical factor influencing university students’well-being.However,research has shown that stress is not a unidimensional construct;different types of stressors(challenge vs.hindrance)...Background:Academic stress is a critical factor influencing university students’well-being.However,research has shown that stress is not a unidimensional construct;different types of stressors(challenge vs.hindrance)may lead to distinct outcomes.This study constructed a structural equation model(SEM)to examine the relationships between challenge and hindrance academic stressors and students’well-being,as well as the mediating mechanisms.Methods:Data were collected from 836 undergraduates at six universities in China(58.4%female,41.6%male;Mean age=20.47±1.46 years).Descriptive statistics,Pearson correlations,and SEM with 5000 bootstrap resamples were conducted to test hypothesized paths and mediating effects.Results:Direct path analysis revealed that challenge stressors positively predicted meaning in life(β=0.329,p<0.001)but not academic self-efficacy(β=-0.004,p=0.915),while hindrance stressors negatively predicted meaning in life(β=-0.371,p<0.001).Meaning in life strongly predicted academic self-efficacy(β=0.543,p<0.001)and well-being(β=0.301,p<0.001),and academic self-efficacy further contributed to well-being(β=0.190,p<0.001).Bootstrapping confirmed that meaning in life significantly mediated the effects of both challenge(β=0.099,95%CI[0.063,0.144])and hindrance stressors(β=-0.112,95%CI[-0.162,-0.076])on well-being.The serial mediation pathway was also significant for both models(challenge:β=0.034,95%CI[0.019,0.049];hindrance:β=-0.038,95%CI[-0.057,-0.024]).Conclusions:This study partially validates the dual-pathway model of academic stress in higher education and highlights the pivotal roles of meaning in life and academic self-efficacy in the stress-well-being relationship.展开更多
Stroke,particularly ischemic stroke,is the leading cause of long-term disability and mortality worldwide.It occurs due to the occlusion of the cerebral arteries,which significantly reduces the delivery of blood,oxygen...Stroke,particularly ischemic stroke,is the leading cause of long-term disability and mortality worldwide.It occurs due to the occlusion of the cerebral arteries,which significantly reduces the delivery of blood,oxygen,and essential nutrients to brain tissues.This deprivation triggers a cascade of cellular events that ultimately leads to neuronal death.Recent studies have clarified the multifactorial pathogenesis of ischemic stroke,highlighting the roles of energy failure,excitotoxicity,oxidative stress,neuroinflammation,and apoptosis.This review aimed to provide a comprehensive insight into the fundamental mechanisms driving neuronal death triggered by ischemia and to examine the progress of neuroprotective therapeutic approaches designed to mitigate neuronal loss and promote neurological recovery after a stroke.Additionally,we explored widely accepted findings regarding the potential pathways implicated in neuronal death during ischemic stroke,including the interplay of apoptosis,autophagy,pyroptosis,ferroptosis,and necrosis,which collectively influence neuronal fate.We also discussed advancements in neuroprotective therapeutics,encompassing a range of interventions from pharmacological modulation to stem cell-based therapies,aimed at reducing neuronal injury and enhancing functional recovery following ischemic stroke.Despite these advancements,challenges remain in translating mechanistic insights into effective clinical therapies.Although neuroprotective strategies have shown promise in preclinical models,their efficacy in human trials has been inconsistent,often due to the complex pathology of ischemic stroke and the timing of interventions.In conclusion,this review synthesizes mechanistic insights into the intricate interplay of molecular and cellular pathways driving neuronal death post-ischemia.It sheds light on cutting-edge advancements in potential neuroprotective therapeutics,underscores the promise of regenerative medicine,and offers a forward-looking perspective on potential clinical breakthroughs.The ongoing evolution of precision-targeted interventions is expected to significantly enhance preventative strategies and improve clinical outcomes.展开更多
Carbon superstructures with multiscale hierarchies and functional attributes represent an appealing cathode candidate for zinc hybrid capacitors,but their tailor-made design to optimize the capacitive activity remains...Carbon superstructures with multiscale hierarchies and functional attributes represent an appealing cathode candidate for zinc hybrid capacitors,but their tailor-made design to optimize the capacitive activity remains a confusing topic.Here we develop a hydrogen-bond-oriented interfacial super-assembly strategy to custom-tailor nanosheet-intertwined spherical carbon superstructures(SCSs)for Zn-ion storage with double-high capacitive activity and durability.Tetrachlorobenzoquinone(H-bond acceptor)and dimethylbenzidine(H-bond donator)can interact to form organic nanosheet modules,which are sequentially assembled,orientally compacted and densified into well-orchestrated superstructures through multiple H-bonds(N-H···O).Featured with rich surface-active heterodiatomic motifs,more exposed nanoporous channels,and successive charge migration paths,SCSs cathode promises high accessibility of built-in zincophilic sites and rapid ion diffusion with low energy barriers(3.3Ωs-0.5).Consequently,the assembled Zn||SCSs capacitor harvests all-round improvement in Zn-ion storage metrics,including high energy density(166 Wh kg-1),high-rate performance(172 m Ah g^(-1)at 20 A g^(-1)),and long-lasting cycling lifespan(95.5%capacity retention after 500,000 cycles).An opposite chargecarrier storage mechanism is rationalized for SCSs cathode to maximize spatial capacitive charge storage,involving high-kinetics physical Zn^(2+)/CF_(3)SO_(3)-adsorption and chemical Zn^(2+)redox with carbonyl/pyridine groups.This work gives insights into H-bond-guided interfacial superassembly design of superstructural carbons toward advanced energy storage.展开更多
Stroke is the leading cause of mortality globally,ultimately leading to severe,lifelong neurological impairments.Patients often suffer from a secondary cascade of damage,including neuroinflammation,cytotoxicity,oxidat...Stroke is the leading cause of mortality globally,ultimately leading to severe,lifelong neurological impairments.Patients often suffer from a secondary cascade of damage,including neuroinflammation,cytotoxicity,oxidative stress,and mitochondrial dysfunction.Regrettably,there is a paucity of clinically available therapeutics to address these issues.Emerging evidence underscores the pivotal roles of astrocytes,the most abundant glial cells in the brain,throughout the various stages of ischemic stroke.In this comprehensive review,we initially provide an overview of the fundamental physiological functions of astrocytes in the brain,emphasizing their critical role in modulating neuronal homeostasis,synaptic activity,and blood-brain barrier integrity.We then delve into the growing body of evidence that highlights the functional diversity and heterogeneity of astrocytes in the context of ischemic stroke.Their well-established contributions to energy provision,metabolic regulation,and neurotransmitter homeostasis,as well as their emerging roles in mitochondrial recovery,neuroinflammation regulation,and oxidative stress modulation following ischemic injury,are discussed in detail.We also explore the cellular and molecular mechanisms underpinning these functions,with particular emphasis on recently identified targets within astrocytes that offer promising prospects for therapeutic intervention.In the final section of this review,we offer a detailed overview of the current therapeutic strategies targeting astrocytes in the treatment of ischemic stroke.These astrocyte-targeting strategies are categorized into traditional small-molecule drugs,microRNAs(miRNAs),stem cell-based therapies,cellular reprogramming,hydrogels,and extracellular vesicles.By summarizing the current understanding of astrocyte functions and therapeutic targeting approaches,we aim to highlight the critical roles of astrocytes during and after stroke,particularly in the pathophysiological development in ischemic stroke.We also emphasize promising avenues for novel,astrocyte-targeted therapeutics that could become clinically available options,ultimately improving outcomes for patients with stroke.展开更多
[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucid...[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucidating the global response patterns of soil moisture to vegetation restoration and identifying research hotspots are critical for guiding ecological construction in arid regions.[Methods]We reviewed 6,152 articles concerning soil moisture and vegetation retrieved from the Web of Science platform.Using VOSviewer,we conducted analyses of keyword co-occurrence,publication trends,and research hotspots to systematically delineate the evolving trends in this field.[Results]The results indicate a significant increasing trend in the number of publications since 2000.Global research keywords are categorized into seven clusters,including vegetation,soil moisture,rainfall-erosion-infiltration,spatial heterogeneity,and climate change.In terms of highly cited papers in 2024,China and the United States maintain a significant lead.Global research demonstrates a strong dependency on typical regional geographical features(such as climate types and topography),exhibiting differentiated research focuses.Furthermore,studies extend beyond soil moisture itself to deeply couple with ecological processes such as vegetation restoration,soil respiration,carbon cycling,and hydrothermal conditions.[Conclusions]The long-term ecological effects of afforestation in arid regions remain unclear,and empirical data from key regions highlight the current urgency.Future research should integrate climate change dynamics,innovate monitoring methodologies,and deepen the understanding of regional differentiation to provide scientific support for the adaptive management of vegetation in arid regions.展开更多
Perihilar cholangiocarcinoma(pCCA)and intrahepatic cholangiocarcinoma(iCCA)are highly malignant neoplasms with a 5-year overall survival rate of approximately 30%[1,2].Surgical resection remains the only potentially c...Perihilar cholangiocarcinoma(pCCA)and intrahepatic cholangiocarcinoma(iCCA)are highly malignant neoplasms with a 5-year overall survival rate of approximately 30%[1,2].Surgical resection remains the only potentially curative treatment,yet only one-fifth of patients are eligible for resection at initial diagnosis[3].Threedimensional(3D)reconstruction technology provides precise preoperative visualization of complex hilar anatomy,significantly enhancing surgical planning and outcomes[4].Recent advances in 3D reconstruction technology have enhanced preoperative planning by providing precise anatomical mapping of tumor-vessel relationships and biliary variations[4,5].Therefore,this report describes a case of left iCCA successfully resected with biliary reconstruction guided by 3D visualization.展开更多
Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,su...Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,suffer from accuracy degradation,omission of critical discontinuities when orientation density is unevenly distributed,and need manual intervention.To overcome these limitations,this paper introduces a novel discontinuities identificationmethod based on geometric feature analysis of rock mass.By analyzing spatial distribution variability of point cloud and integrating an adaptive region growing algorithm,the method accurately detects independent discontinuities under complex geological conditions.Given that rock mass orientations typically follow a Fisher distribution,an adaptive hierarchical clustering algorithm based on statistical analysis is employed to automatically determine the optimal number of structural sets,eliminating the need for preset clusters or thresholds inherent in traditional methods.The proposed approach effectively handles diverse rock mass shapes and sizes,leveraging both local and global geometric features to minimize noise interference.Experimental validation on three real-world rock mass models,alongside comparisons with three conventional directional clustering algorithms,demonstrates superior accuracy and robustness in identifying optimal discontinuity sets.The proposed method offers a reliable and efficienttool for discontinuities detection and grouping in underground engineering,significantlyenhancing design and construction outcomes.展开更多
Gravity-caisson wharves have been widely constructed in coastal and island regions, which are threaten by potential underwater explosions. This work aims to study the dynamic behaviors and propose a damage evaluation ...Gravity-caisson wharves have been widely constructed in coastal and island regions, which are threaten by potential underwater explosions. This work aims to study the dynamic behaviors and propose a damage evaluation approach of caisson wharf against underwater explosion. Firstly, based on both the underwater explosion loading test and underwater explosion test on the reduced-scale caisson specimen, a high-fidelity finite element analysis approach for numerically reproduce the dynamic behaviors of prototype caisson wharves against underwater explosions was proposed and verified. Secondly, the underwater explosion loadings and dynamic behaviors of prototype caisson wharf (14.9 m×8.1 m×10.95 m) against sequential blast wave and bubble pulsation of typical torpedo with a charge weight of 200 kg were studied. The influences of the seabed and cabin infill materials, as well as the explosion standoff distances of 3.4–10.2 m and depths of burst between 1/4 and 3/4 of water depth, on the blast resistance of caisson wharf were further examined through deflection distributions of exterior wall, damage evolution, and overall displacement of caisson wharf. Finally, a performance evaluation approach for prototype caisson wharves against underwater explosions was proposed by comprehensively considering the bearing, storage, and berthing capabilities. The corresponding protective measures and design recommendations were further provided. It indicates that: (i) under the explosion of a typical torpedo, the damage modes of prototype caisson wharf mainly involve the overall vibration, spalling and cracking of the exterior wall, collapse of the upper operating platform and cracking of the top plate;(ii) the blast wave and cavitation zone generated between the bubble and the exterior wall are the two primary causes of damage to caisson wharf;(iii) compared to the saturated calcareous sand seabed, the assumption of rigid seabed underestimates the spalling on the exterior wall, which is not recommended for scenarios where cavitation zones may generate;(iv) rock rubble is the most effective infill material in improving the blast resistance of caisson wharf among four types of infill configurations, i.e., fully filled and half-filled saturated calcareous sand, rock rubble and pure water;(v) the standoff distance of 10.2 m is regarded as a secure protective range in the scenarios discussed currently. As the standoff distance decreases and the depth of burst increases, the spalling of the exterior wall induced by the cavitation intensifies, posing a great threat to the functionality of caisson wharf.展开更多
Aerobic exercise facilitates synaptic plasticity,thereby improving cognitive functions such as learning and memory.The 5-hydroxytryptamine system has been indicated in these processes.5-Hydroxytryptamine type 3 recept...Aerobic exercise facilitates synaptic plasticity,thereby improving cognitive functions such as learning and memory.The 5-hydroxytryptamine system has been indicated in these processes.5-Hydroxytryptamine type 3 receptors are necessary for exercise-induced hippocampal neurogenesis.Some antipsychotic drugs with 5-hydroxytryptamine type 3 receptor antagonistic properties may impede the amelioration of cognitive impairment and hippocampal plasticity induced by exercise.However,the mechanisms underlying the facilitation of synaptic plasticity by aerobic exercise have not yet been elucidated.In this study,we found that 5-hydroxytryptamine type 3 receptors played an important role in aerobic exercise-mediated improvement of hippocampal-dependent spatial and exploratory memory in mice.While 5-hydroxytryptamine type 3 receptors did not affect baseline neurogenesis in the hippocampal dentate gyrus,5-hydroxytryptamine type 3 receptors were required for aerobic exercise-induced neurogenesis and astrocyte proliferation in this region.In addition,5-hydroxytryptamine type 3 receptors were crucial for maintaining long-term potentiation in the CA1,dentate gyrus,and CA3 regions of the hippocampus.The long-term potentiation changes induced by aerobic exercise in sub-regions of the hippocampus were heterogeneous:5-hydroxytryptamine type 3 receptors were essential for aerobic exercise to enhance long-term potentiation in the CA3,but not the CA1 or dentate gyrus,regions of the hippocampus.Furthermore,aerobic exercise up-regulated 5-hydroxytryptamine type 3 receptor expression and increased brain-derived neurotrophic factor release in the hippocampus in a 5-hydroxytryptamine type 3 receptor-dependent manner.These results suggest that aerobic exercise increases hippocampal dentate gyrus neurogenesis and astrocyte proliferation via the up-regulation of 5-hydroxytryptamine type 3 receptors,leading to more brain-derived neurotrophic factor production and release from these cells,which results in long-term potentiation facilitation in the hippocampal CA3 region and help improve memory.Our findings provide insight into the mechanisms by which physical activity enhances memory and may have implications for improving memory through modulating 5-hydroxytryptamine type 3 receptor.展开更多
Background:Hepatocellular carcinoma(HCC)is one of the leading causes of cancer-related mortality worldwide.This study aimed to identify key genes involved in HCC development and elucidate their molecular mechanisms,wi...Background:Hepatocellular carcinoma(HCC)is one of the leading causes of cancer-related mortality worldwide.This study aimed to identify key genes involved in HCC development and elucidate their molecular mechanisms,with a particular focus on mitochondrial function and apoptosis.Methods:Differential expression analyses were performed across three datasets—The Cancer Genome Atlas(TCGA)-Liver Hepatocellular Carcinoma(LIHC),GSE36076,and GSE95698—to identify overlapping differentially expressed genes(DEGs).A prognostic risk model was then constructed.Cysteine/serine-rich nuclear protein 1(CSRNP1)expression levels in HCC cell lines were assessed via western blot(WB)and quantitative reverse transcription polymerase chain reaction(qRT-PCR).The effects of CSRNP1 knockdown or overexpression on cell proliferation,migration,and apoptosis were evaluated using cell counting-8(CCK-8)assays,Transwell assays,and flow cytometry.Mitochondrial ultrastructure was examined by transmission electron microscopy,and intracellular and mitochondrial reactive oxygen species(mROS)levels were measured using specific fluorescent probes.WB was used to assess activation of the c-Jun N-terminal kinase(JNK)/p38 mitogen-activated protein kinase(MAPK)pathway,and pathway dependence was examined using the ROS scavenger N-Acetylcysteine(NAC)and the JNK inhibitor SP600125.Results:A six-gene prognostic model was established,comprising downregulated genes(NR4A1 and CSRNP1)and upregulated genes(CENPQ,YAE1,FANCF,and POC5)in HCC.Functional experiments revealed that CSRNP1 knockdown promoted the proliferation of HCC cells and suppressed their apoptosis.Conversely,CSRNP1 overexpression impaired mitochondrial integrity,increased both mitochondrial and cytoplasmic ROS levels,and activated the JNK/p38 MAPK pathway.Notably,treatment with NAC or SP600125 attenuated CSRNP1-induced MAPK activation and apoptosis.Conclusion:CSRNP1 is a novel prognostic biomarker and tumor suppressor in HCC.It exerts anti-tumor effects by inducing oxidative stress and activating the JNK/p38 MAPK pathway in a ROS-dependent manner.These findings suggest that CSRNP1 may serve as a potential therapeutic target in the management of HCC.展开更多
The Hall effect of elastic waves has attracted much attention due to its unique properties.A hexagonal lattice phononic crystal plate model is designed in this paper.By changing the spatial symmetry of the unit cell,a...The Hall effect of elastic waves has attracted much attention due to its unique properties.A hexagonal lattice phononic crystal plate model is designed in this paper.By changing the spatial symmetry of the unit cell,a band gap for the A_(0) Lamb wave is opened.The existence of the edge state of the phononic crystal plate is obtained by finite element simulation.It is found that both zigzag-type edge and bridge edge are topological edge states by analysis of the band structure of the supercell.A rectangular model with a straight channel is designed and the simulation results show that the two types of channels are topologically protected only for the A_(0) mode Lamb wave but not for the S_(0) mode.In addition,the results of numerical simulation are verified by experimental data measured by a laser vibrometer.Finally,it is found that neither upside V-shaped channels nor channels with defects will affect the stable propagation of A_(0) Lamb waves along the proposed route.This proposed model and method are helpful in broadening the means of regulating elastic waves in phononic crystal structures,and extending practical application of topological edge states in such structures.展开更多
The stator of the maglev track plays a crucial role in the operation of the maglev system.Currently,the efficiency of maglev track inspection is limited by several factors,including the large span of elevated structur...The stator of the maglev track plays a crucial role in the operation of the maglev system.Currently,the efficiency of maglev track inspection is limited by several factors,including the large span of elevated structures,manual visual inspection,short inspection window times,and limited GPS positioning accuracy.To address these issues,this paper proposes a deep learning-based method for detecting and locating stator surface damage.This study establishes a maglev track stator surface image dataset,trains different object detection models,and compares their performance.Ultimately,YOLO and ByteTrack object tracking algorithms were chosen as the basic framework and enhanced to achieve automatic identification of high-speed maglev track stator surface damage images and track and count stator surface localization feature images.By matching the identified damaged images with their corresponding stator segment and beam segment sequence numbers,the location of the damage is pinpointed to the corresponding stator segment,enabling rapid and accurate identification and localization of complex damage to the maglev track stator surface.展开更多
The presence or absence of adult neural stem cells in the mammalian forebrain ependyma has been debated for two decades.In this study,we performed single-cell RNA sequencing to investigate the cellular composition of ...The presence or absence of adult neural stem cells in the mammalian forebrain ependyma has been debated for two decades.In this study,we performed single-cell RNA sequencing to investigate the cellular composition of the ependymal surface of the adult mouse forebrain using whole mounts of lateral walls of lateral ventricles.We identified 12 different cell subtypes in the ependymal surface.Immunocytochemical analyses revealed that CD133^(+)multi-ciliated cells comprised 67.6%of ependymal cells,while the remaining 32.4%were CD133^(-).CD133^(+)ependymal cells can be further classified into FOXJ1^(+)/SOX2^(+)/ACTA2^(+)cells,FLT1^(+)/CD31^(+)/CLDN5^(+)endothelial-like cells,and PDGFRB^(+)/VTN^(+)/NG2^(+)pericyte-like cells,as well as endothelial-pericyte-like cells and Foxj1^(+)endothelial-like cells.CD133^(-)ependymal cells can be further divided into endothelial-like cells,Foxj1^(+)ependymal cells,Foxj1^(+)endothelial-like cells,pericyte-like cells,endothelial-pericyte-like cells,VIM^(+)cells,and cells negative for all of these markers.This comprehensive profiling confirms the heterogeneity of the ependymal surface in the adult mouse forebrain.Debate regarding whether adult ependymal cells contain neural stem cells has arisen because different researchers have examined different populations of ependymal cells.Our study provides a new perspective for investigation of clinical endogenous neural stem cells,ultimately paving the way for stem cell therapies in neurological diseases.展开更多
In the early stages of traumatic spinal cord injury,extensive accumulation of autophagosomes creates a neurotoxic microenvironment,exacerbating neuronal cell death and worsening tissue damage,ultimately hindering neur...In the early stages of traumatic spinal cord injury,extensive accumulation of autophagosomes creates a neurotoxic microenvironment,exacerbating neuronal cell death and worsening tissue damage,ultimately hindering neurofunctional recovery.Activin A is a critical growth factor necessary for the development of the embryonic nervous system and for maintaining neuronal function in the adult cerebral cortex.It can inhibit excessive autophagy in ischemic stroke to reduce neuronal damage.However,the specific mechanism through which Activin A functions in the spinal cord remains poorly understood.In this study,we administered different concentrations of Activin A to neural stem cells from the spinal cord and found that Activin A stimulated the proliferation and neuronal differentiation of neural stem cells.Then,we established an in vitro oxidative stress model by using hydrogen peroxide to stimulate the neural stem cells-induced neurons.We found that Activin A could reduce apoptosis caused by oxidative stress.Subsequently,we treated a mouse model of spinal cord contusion with intrathecal injection of Activin A.Behavioral and electrophysiological results showed that Activin A promoted recovery of motor function and reconstruction of neural circuits in the model mice.Finally,RNA sequencing indicated that Activin A inhibited autophagy by activating the PI3K/AKT/mTOR pathway and upregulating the expression of synaptogenesis-related factor Sema3A in the spinal cord.These results suggest that Activin A may mediate the excessive autophagic response after spinal cord injury,promote the reconstruction of damaged neural circuits,and restore neurological function in the injured spinal cord.展开更多
Inverse design of advanced materials represents a pivotal challenge in materials science.Leveraging the latent space of Variational Autoencoders(VAEs)for material optimization has emerged as a significant advancement ...Inverse design of advanced materials represents a pivotal challenge in materials science.Leveraging the latent space of Variational Autoencoders(VAEs)for material optimization has emerged as a significant advancement in the field of material inverse design.However,VAEs are inherently prone to generating blurred images,posing challenges for precise inverse design and microstructure manufacturing.While increasing the dimensionality of the VAE latent space can mitigate reconstruction blurriness to some extent,it simultaneously imposes a substantial burden on target optimization due to an excessively high search space.To address these limitations,this study adopts a Variational Autoencoder guided Conditional Diffusion Generative Model(VAE-CDGM)framework integrated with Bayesian optimization to achieve the inverse design of composite materials with targeted mechanical properties.The VAE-CDGM model synergizes the strengths of VAEs and Denoising Diffusion Probabilistic Models(DDPM),enabling the generation of high-quality,sharp images while preserving a manipulable latent space.To accommodate varying dimensional requirements of the latent space,two optimization strategies are proposed.When the latent space dimensionality is excessively high,SHapley Additive exPlanations(SHAP)sensitivity analysis is employed to identify critical latent features for optimization within a reduced subspace.Conversely,direct optimization is performed in the low-dimensional latent space of VAE-CDGM when dimensionality is modest.The results demonstrate that both strategies accurately achieve the targeted design of composite materials while circumventing the blurred reconstruction flaws of VAEs,which offers a novel pathway for the precise design of advanced materials.展开更多
Abstract To investigate the use of the three-point bending method and supplement the corresponding strength data of compacted snow for transportation-related applications in cold regions,compacted snow beams with an a...Abstract To investigate the use of the three-point bending method and supplement the corresponding strength data of compacted snow for transportation-related applications in cold regions,compacted snow beams with an average density of 592 kg·m−3 were fabricated and tested at three distinct flexural strain rates.Each strain rate corresponded to the ductile,transitional,and brittle behavior of compacted snow,respectively.The flexural strength,ranging from 0.518 to 0.933 MPa,peaks at the ductile-to-brittle transition,while the flexural modulus,varying between 48.97 and 287.72 MPa,increases with strain rate within the tested range.At the same strain rate corresponding to brittle failure,both mechanical properties of compacted snow exhibit higher values than those of natural snow tested by the authors.Notably,the flexural strain rate at the ductile-to-brittle transition for compacted snow identified in this study is comparable to those previously reported for natural snow under uniaxial tension.Additionally,the obtained strength data are thoroughly compared with existing literature,with detailed discussions provided.The loading rates associated with typical failure modes of compacted snow under bending,together with the obtained strength values,provide methodological guidance and reference data for future in situ testing of compacted snow structures.展开更多
Water-sand gushing(WSG)disasters in confinedaquifers pose significantchallenges to the utilization of deep underground spaces in soft soil areas.Since few studies have considered the impact of confined aquifer thickne...Water-sand gushing(WSG)disasters in confinedaquifers pose significantchallenges to the utilization of deep underground spaces in soft soil areas.Since few studies have considered the impact of confined aquifer thickness and confinedwater pressure on WSG disasters,a novel visual model test system was developed to investigate the influencingcharacteristics and mechanisms of the two aforementioned factors.The test results showed that the WSG process in clay aquiclude-confinedaquifer composite strata exhibits two prominent stages.First,the sand loss zone expands vertically in an ellipsoid shape.Then,it expands horizontally once the ellipsoid reaches the boundary of the clay layer.The sand loss continues until the overlying clay sinks to the bottom to clog the gushing crack,creating a large sinkhole at the surface.Increasing the confinedaquifer thickness can increase the vertical expansion of the ellipsoid and delay the clay-clogging effects,thereby considerably increasing the severity of sand loss,stratum deformation,and surface settlement.An increase in the confinedwater pressure markedly increases the hydraulic gradient along the seepage path,which contributes to increasing the gushing rates of water and sand.As a result,substantial sand loss occurs before the clay clogs the gushing crack,inducing more cracks and deeper sinkholes at the surface.All the aforementioned results provide insights into the effects of confinedaquifer on WSG disasters in clay aquiclude-confinedaquifer composite strata.展开更多
Underground hydrogen storage has gained interest in recent years due to the enormous demand for clean energy.Hydrogen is more diffusive than air,with a smaller density and lower viscosity.These unique properties intro...Underground hydrogen storage has gained interest in recent years due to the enormous demand for clean energy.Hydrogen is more diffusive than air,with a smaller density and lower viscosity.These unique properties introduce distinctive hydrodynamic phenomena in hydrogen storage,one of which is fingering.Fingering could induce the fluid trapped in small clusters of pores,leading to a dramatic decrease in hydrogen saturation and a lower recovery rate.In this study,numerical simulations are performed at the microscopic scale to understand the evolution of hydrogen saturation and the impacts of injection and withdrawal cycles.Two sets of micromodels with different porosity(0.362 and 0.426)and minimum sizes of pore throats(0.362 mm and 0.181 mm)are developed in the numerical model.A parameter analysis is then conducted to understand the influence of injection velocity(in the range of 10^(-2)m/s to 10^(-5)m/s)and porous structure on the fingering pattern,followed by an image analysis to capture the evolution of the fingering pattern.Viscous fingering,capillary fingering,and crossover fingering are observed and identified under different boundary conditions.The fractal dimension,specific area,mean angle,and entropy of fingers are proposed as geometric descriptors to characterize the shape of the fingering pattern.When porosity increases from 0.362 to 0.426,the saturation of hydrogen increases by 26.2%.Narrower pore throats elevate capillary resistance,which hinders fluid invasion.These results underscore the importance of pore structures and the interaction between viscous and capillary forces for hydrogen recovery efficiency.This work illuminates the influence of the pore structures and the fluid properties on the immiscible displacement of hydrogen and can be further extended to optimize the injection strategy of hydrogen in underground hydrogen storage.展开更多
基金the National Natural Science Foundation of China under the contract numbers 60178021,60378021 , 10435050 National High Technology Research and Development“863”Program of China.(No.3)
文摘In EUV and X- ray regions, multilayer mirrors are the essential and necessary optics elements. The good prospects of the EUV and X- rays for next generation lithography system, microscopy in the “water windows”, astro- nomical telescope, spectroscopy, plasma diagnostics, and X- ray laser have impelled the development of multilayer optics. The paper introduces the recent results of the multilayer optics elements in Tongji University, including beam splitters, broadband/angular polarizers, supermirrors and high- reflectance mirrors. The product of reflectivity and transmissivity is above 4% for the Mo/Si multilayer beam splitter. Over the 15￣17 nm wavelength range, the s- re- flectivity of the non- periodic Mo/Si broadband multilayer polarizers is reasonably constant, as high as 36.6%, and the degree of polarization is more than 97.8%. At the fixed energy of 8 keV (Cu Kαline), the W/Si supermirror has the reflectivity of above 30% in the angle range of 0.4°￣0.85°, and a W/B4C supermirror has the reflectivity of about 20% in the angle range of 0.9°￣1.2°, and the reflectivity of W/C supermirror working in the grazing incident angle range of 0.9°￣1.2°is about 20%. The experimental results of some high- reflectance mirrors in our lab are also pre- sented, such as Mo/Si, Mo/Y, Cr/C, La/B4C, Si/C and Si/SiC. The reflectivity of Mo/Si multilayer is as high as 61.1% at wavelength of 13.4 nm.
文摘Background:Academic stress is a critical factor influencing university students’well-being.However,research has shown that stress is not a unidimensional construct;different types of stressors(challenge vs.hindrance)may lead to distinct outcomes.This study constructed a structural equation model(SEM)to examine the relationships between challenge and hindrance academic stressors and students’well-being,as well as the mediating mechanisms.Methods:Data were collected from 836 undergraduates at six universities in China(58.4%female,41.6%male;Mean age=20.47±1.46 years).Descriptive statistics,Pearson correlations,and SEM with 5000 bootstrap resamples were conducted to test hypothesized paths and mediating effects.Results:Direct path analysis revealed that challenge stressors positively predicted meaning in life(β=0.329,p<0.001)but not academic self-efficacy(β=-0.004,p=0.915),while hindrance stressors negatively predicted meaning in life(β=-0.371,p<0.001).Meaning in life strongly predicted academic self-efficacy(β=0.543,p<0.001)and well-being(β=0.301,p<0.001),and academic self-efficacy further contributed to well-being(β=0.190,p<0.001).Bootstrapping confirmed that meaning in life significantly mediated the effects of both challenge(β=0.099,95%CI[0.063,0.144])and hindrance stressors(β=-0.112,95%CI[-0.162,-0.076])on well-being.The serial mediation pathway was also significant for both models(challenge:β=0.034,95%CI[0.019,0.049];hindrance:β=-0.038,95%CI[-0.057,-0.024]).Conclusions:This study partially validates the dual-pathway model of academic stress in higher education and highlights the pivotal roles of meaning in life and academic self-efficacy in the stress-well-being relationship.
基金supported by the National Natural Science Foundation of China,Nos.82171387 and 31830111(both to SL).
文摘Stroke,particularly ischemic stroke,is the leading cause of long-term disability and mortality worldwide.It occurs due to the occlusion of the cerebral arteries,which significantly reduces the delivery of blood,oxygen,and essential nutrients to brain tissues.This deprivation triggers a cascade of cellular events that ultimately leads to neuronal death.Recent studies have clarified the multifactorial pathogenesis of ischemic stroke,highlighting the roles of energy failure,excitotoxicity,oxidative stress,neuroinflammation,and apoptosis.This review aimed to provide a comprehensive insight into the fundamental mechanisms driving neuronal death triggered by ischemia and to examine the progress of neuroprotective therapeutic approaches designed to mitigate neuronal loss and promote neurological recovery after a stroke.Additionally,we explored widely accepted findings regarding the potential pathways implicated in neuronal death during ischemic stroke,including the interplay of apoptosis,autophagy,pyroptosis,ferroptosis,and necrosis,which collectively influence neuronal fate.We also discussed advancements in neuroprotective therapeutics,encompassing a range of interventions from pharmacological modulation to stem cell-based therapies,aimed at reducing neuronal injury and enhancing functional recovery following ischemic stroke.Despite these advancements,challenges remain in translating mechanistic insights into effective clinical therapies.Although neuroprotective strategies have shown promise in preclinical models,their efficacy in human trials has been inconsistent,often due to the complex pathology of ischemic stroke and the timing of interventions.In conclusion,this review synthesizes mechanistic insights into the intricate interplay of molecular and cellular pathways driving neuronal death post-ischemia.It sheds light on cutting-edge advancements in potential neuroprotective therapeutics,underscores the promise of regenerative medicine,and offers a forward-looking perspective on potential clinical breakthroughs.The ongoing evolution of precision-targeted interventions is expected to significantly enhance preventative strategies and improve clinical outcomes.
基金financially supported by the National Natural Science Foundation of China(Nos.22272118,22172111,and 22309134)the Science and Technology Commission of Shanghai Municipality,China(Nos.22ZR1464100,20ZR1460300,and 19DZ2271500)+2 种基金the China Postdoctoral Science Foundation(2022M712402),the Shanghai Rising-Star Program(23YF1449200)the Zhejiang Provincial Science and Technology Project(2022C01182)the Fundamental Research Funds for the Central Universities(2023-3-YB-07)。
文摘Carbon superstructures with multiscale hierarchies and functional attributes represent an appealing cathode candidate for zinc hybrid capacitors,but their tailor-made design to optimize the capacitive activity remains a confusing topic.Here we develop a hydrogen-bond-oriented interfacial super-assembly strategy to custom-tailor nanosheet-intertwined spherical carbon superstructures(SCSs)for Zn-ion storage with double-high capacitive activity and durability.Tetrachlorobenzoquinone(H-bond acceptor)and dimethylbenzidine(H-bond donator)can interact to form organic nanosheet modules,which are sequentially assembled,orientally compacted and densified into well-orchestrated superstructures through multiple H-bonds(N-H···O).Featured with rich surface-active heterodiatomic motifs,more exposed nanoporous channels,and successive charge migration paths,SCSs cathode promises high accessibility of built-in zincophilic sites and rapid ion diffusion with low energy barriers(3.3Ωs-0.5).Consequently,the assembled Zn||SCSs capacitor harvests all-round improvement in Zn-ion storage metrics,including high energy density(166 Wh kg-1),high-rate performance(172 m Ah g^(-1)at 20 A g^(-1)),and long-lasting cycling lifespan(95.5%capacity retention after 500,000 cycles).An opposite chargecarrier storage mechanism is rationalized for SCSs cathode to maximize spatial capacitive charge storage,involving high-kinetics physical Zn^(2+)/CF_(3)SO_(3)-adsorption and chemical Zn^(2+)redox with carbonyl/pyridine groups.This work gives insights into H-bond-guided interfacial superassembly design of superstructural carbons toward advanced energy storage.
基金supported by the National Natural Science Foundation of China,No.82001325Visiting Scholar Foundation of Shandong Province,No.20236-01(both to CS).
文摘Stroke is the leading cause of mortality globally,ultimately leading to severe,lifelong neurological impairments.Patients often suffer from a secondary cascade of damage,including neuroinflammation,cytotoxicity,oxidative stress,and mitochondrial dysfunction.Regrettably,there is a paucity of clinically available therapeutics to address these issues.Emerging evidence underscores the pivotal roles of astrocytes,the most abundant glial cells in the brain,throughout the various stages of ischemic stroke.In this comprehensive review,we initially provide an overview of the fundamental physiological functions of astrocytes in the brain,emphasizing their critical role in modulating neuronal homeostasis,synaptic activity,and blood-brain barrier integrity.We then delve into the growing body of evidence that highlights the functional diversity and heterogeneity of astrocytes in the context of ischemic stroke.Their well-established contributions to energy provision,metabolic regulation,and neurotransmitter homeostasis,as well as their emerging roles in mitochondrial recovery,neuroinflammation regulation,and oxidative stress modulation following ischemic injury,are discussed in detail.We also explore the cellular and molecular mechanisms underpinning these functions,with particular emphasis on recently identified targets within astrocytes that offer promising prospects for therapeutic intervention.In the final section of this review,we offer a detailed overview of the current therapeutic strategies targeting astrocytes in the treatment of ischemic stroke.These astrocyte-targeting strategies are categorized into traditional small-molecule drugs,microRNAs(miRNAs),stem cell-based therapies,cellular reprogramming,hydrogels,and extracellular vesicles.By summarizing the current understanding of astrocyte functions and therapeutic targeting approaches,we aim to highlight the critical roles of astrocytes during and after stroke,particularly in the pathophysiological development in ischemic stroke.We also emphasize promising avenues for novel,astrocyte-targeted therapeutics that could become clinically available options,ultimately improving outcomes for patients with stroke.
文摘[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucidating the global response patterns of soil moisture to vegetation restoration and identifying research hotspots are critical for guiding ecological construction in arid regions.[Methods]We reviewed 6,152 articles concerning soil moisture and vegetation retrieved from the Web of Science platform.Using VOSviewer,we conducted analyses of keyword co-occurrence,publication trends,and research hotspots to systematically delineate the evolving trends in this field.[Results]The results indicate a significant increasing trend in the number of publications since 2000.Global research keywords are categorized into seven clusters,including vegetation,soil moisture,rainfall-erosion-infiltration,spatial heterogeneity,and climate change.In terms of highly cited papers in 2024,China and the United States maintain a significant lead.Global research demonstrates a strong dependency on typical regional geographical features(such as climate types and topography),exhibiting differentiated research focuses.Furthermore,studies extend beyond soil moisture itself to deeply couple with ecological processes such as vegetation restoration,soil respiration,carbon cycling,and hydrothermal conditions.[Conclusions]The long-term ecological effects of afforestation in arid regions remain unclear,and empirical data from key regions highlight the current urgency.Future research should integrate climate change dynamics,innovate monitoring methodologies,and deepen the understanding of regional differentiation to provide scientific support for the adaptive management of vegetation in arid regions.
基金supported by grants from the National Natural Science Foundation of China(82170412)Shanghai Municipal Science and Technology Commission Clinical Innovation Research Special Project(23Y11905400).
文摘Perihilar cholangiocarcinoma(pCCA)and intrahepatic cholangiocarcinoma(iCCA)are highly malignant neoplasms with a 5-year overall survival rate of approximately 30%[1,2].Surgical resection remains the only potentially curative treatment,yet only one-fifth of patients are eligible for resection at initial diagnosis[3].Threedimensional(3D)reconstruction technology provides precise preoperative visualization of complex hilar anatomy,significantly enhancing surgical planning and outcomes[4].Recent advances in 3D reconstruction technology have enhanced preoperative planning by providing precise anatomical mapping of tumor-vessel relationships and biliary variations[4,5].Therefore,this report describes a case of left iCCA successfully resected with biliary reconstruction guided by 3D visualization.
基金the National Key Research and Development Program of China(Grant No.2023YFC3009400).
文摘Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,suffer from accuracy degradation,omission of critical discontinuities when orientation density is unevenly distributed,and need manual intervention.To overcome these limitations,this paper introduces a novel discontinuities identificationmethod based on geometric feature analysis of rock mass.By analyzing spatial distribution variability of point cloud and integrating an adaptive region growing algorithm,the method accurately detects independent discontinuities under complex geological conditions.Given that rock mass orientations typically follow a Fisher distribution,an adaptive hierarchical clustering algorithm based on statistical analysis is employed to automatically determine the optimal number of structural sets,eliminating the need for preset clusters or thresholds inherent in traditional methods.The proposed approach effectively handles diverse rock mass shapes and sizes,leveraging both local and global geometric features to minimize noise interference.Experimental validation on three real-world rock mass models,alongside comparisons with three conventional directional clustering algorithms,demonstrates superior accuracy and robustness in identifying optimal discontinuity sets.The proposed method offers a reliable and efficienttool for discontinuities detection and grouping in underground engineering,significantlyenhancing design and construction outcomes.
基金supported by National Natural Science Foundations of China(Grant No.52308522).
文摘Gravity-caisson wharves have been widely constructed in coastal and island regions, which are threaten by potential underwater explosions. This work aims to study the dynamic behaviors and propose a damage evaluation approach of caisson wharf against underwater explosion. Firstly, based on both the underwater explosion loading test and underwater explosion test on the reduced-scale caisson specimen, a high-fidelity finite element analysis approach for numerically reproduce the dynamic behaviors of prototype caisson wharves against underwater explosions was proposed and verified. Secondly, the underwater explosion loadings and dynamic behaviors of prototype caisson wharf (14.9 m×8.1 m×10.95 m) against sequential blast wave and bubble pulsation of typical torpedo with a charge weight of 200 kg were studied. The influences of the seabed and cabin infill materials, as well as the explosion standoff distances of 3.4–10.2 m and depths of burst between 1/4 and 3/4 of water depth, on the blast resistance of caisson wharf were further examined through deflection distributions of exterior wall, damage evolution, and overall displacement of caisson wharf. Finally, a performance evaluation approach for prototype caisson wharves against underwater explosions was proposed by comprehensively considering the bearing, storage, and berthing capabilities. The corresponding protective measures and design recommendations were further provided. It indicates that: (i) under the explosion of a typical torpedo, the damage modes of prototype caisson wharf mainly involve the overall vibration, spalling and cracking of the exterior wall, collapse of the upper operating platform and cracking of the top plate;(ii) the blast wave and cavitation zone generated between the bubble and the exterior wall are the two primary causes of damage to caisson wharf;(iii) compared to the saturated calcareous sand seabed, the assumption of rigid seabed underestimates the spalling on the exterior wall, which is not recommended for scenarios where cavitation zones may generate;(iv) rock rubble is the most effective infill material in improving the blast resistance of caisson wharf among four types of infill configurations, i.e., fully filled and half-filled saturated calcareous sand, rock rubble and pure water;(v) the standoff distance of 10.2 m is regarded as a secure protective range in the scenarios discussed currently. As the standoff distance decreases and the depth of burst increases, the spalling of the exterior wall induced by the cavitation intensifies, posing a great threat to the functionality of caisson wharf.
基金supported by the National Natural Science Foundation of China,Nos.31972914,31771175(both to YH).
文摘Aerobic exercise facilitates synaptic plasticity,thereby improving cognitive functions such as learning and memory.The 5-hydroxytryptamine system has been indicated in these processes.5-Hydroxytryptamine type 3 receptors are necessary for exercise-induced hippocampal neurogenesis.Some antipsychotic drugs with 5-hydroxytryptamine type 3 receptor antagonistic properties may impede the amelioration of cognitive impairment and hippocampal plasticity induced by exercise.However,the mechanisms underlying the facilitation of synaptic plasticity by aerobic exercise have not yet been elucidated.In this study,we found that 5-hydroxytryptamine type 3 receptors played an important role in aerobic exercise-mediated improvement of hippocampal-dependent spatial and exploratory memory in mice.While 5-hydroxytryptamine type 3 receptors did not affect baseline neurogenesis in the hippocampal dentate gyrus,5-hydroxytryptamine type 3 receptors were required for aerobic exercise-induced neurogenesis and astrocyte proliferation in this region.In addition,5-hydroxytryptamine type 3 receptors were crucial for maintaining long-term potentiation in the CA1,dentate gyrus,and CA3 regions of the hippocampus.The long-term potentiation changes induced by aerobic exercise in sub-regions of the hippocampus were heterogeneous:5-hydroxytryptamine type 3 receptors were essential for aerobic exercise to enhance long-term potentiation in the CA3,but not the CA1 or dentate gyrus,regions of the hippocampus.Furthermore,aerobic exercise up-regulated 5-hydroxytryptamine type 3 receptor expression and increased brain-derived neurotrophic factor release in the hippocampus in a 5-hydroxytryptamine type 3 receptor-dependent manner.These results suggest that aerobic exercise increases hippocampal dentate gyrus neurogenesis and astrocyte proliferation via the up-regulation of 5-hydroxytryptamine type 3 receptors,leading to more brain-derived neurotrophic factor production and release from these cells,which results in long-term potentiation facilitation in the hippocampal CA3 region and help improve memory.Our findings provide insight into the mechanisms by which physical activity enhances memory and may have implications for improving memory through modulating 5-hydroxytryptamine type 3 receptor.
基金funded by Shanghai Yangpu District Science and Technology Commission(Grant No.YPQ202303(Xuejing Lin))Shanghai Yangpu Hospital Foundation(Grant No.Se1202420(Wenchao Wang)and Ye1202423(Juan Huang)).
文摘Background:Hepatocellular carcinoma(HCC)is one of the leading causes of cancer-related mortality worldwide.This study aimed to identify key genes involved in HCC development and elucidate their molecular mechanisms,with a particular focus on mitochondrial function and apoptosis.Methods:Differential expression analyses were performed across three datasets—The Cancer Genome Atlas(TCGA)-Liver Hepatocellular Carcinoma(LIHC),GSE36076,and GSE95698—to identify overlapping differentially expressed genes(DEGs).A prognostic risk model was then constructed.Cysteine/serine-rich nuclear protein 1(CSRNP1)expression levels in HCC cell lines were assessed via western blot(WB)and quantitative reverse transcription polymerase chain reaction(qRT-PCR).The effects of CSRNP1 knockdown or overexpression on cell proliferation,migration,and apoptosis were evaluated using cell counting-8(CCK-8)assays,Transwell assays,and flow cytometry.Mitochondrial ultrastructure was examined by transmission electron microscopy,and intracellular and mitochondrial reactive oxygen species(mROS)levels were measured using specific fluorescent probes.WB was used to assess activation of the c-Jun N-terminal kinase(JNK)/p38 mitogen-activated protein kinase(MAPK)pathway,and pathway dependence was examined using the ROS scavenger N-Acetylcysteine(NAC)and the JNK inhibitor SP600125.Results:A six-gene prognostic model was established,comprising downregulated genes(NR4A1 and CSRNP1)and upregulated genes(CENPQ,YAE1,FANCF,and POC5)in HCC.Functional experiments revealed that CSRNP1 knockdown promoted the proliferation of HCC cells and suppressed their apoptosis.Conversely,CSRNP1 overexpression impaired mitochondrial integrity,increased both mitochondrial and cytoplasmic ROS levels,and activated the JNK/p38 MAPK pathway.Notably,treatment with NAC or SP600125 attenuated CSRNP1-induced MAPK activation and apoptosis.Conclusion:CSRNP1 is a novel prognostic biomarker and tumor suppressor in HCC.It exerts anti-tumor effects by inducing oxidative stress and activating the JNK/p38 MAPK pathway in a ROS-dependent manner.These findings suggest that CSRNP1 may serve as a potential therapeutic target in the management of HCC.
文摘The Hall effect of elastic waves has attracted much attention due to its unique properties.A hexagonal lattice phononic crystal plate model is designed in this paper.By changing the spatial symmetry of the unit cell,a band gap for the A_(0) Lamb wave is opened.The existence of the edge state of the phononic crystal plate is obtained by finite element simulation.It is found that both zigzag-type edge and bridge edge are topological edge states by analysis of the band structure of the supercell.A rectangular model with a straight channel is designed and the simulation results show that the two types of channels are topologically protected only for the A_(0) mode Lamb wave but not for the S_(0) mode.In addition,the results of numerical simulation are verified by experimental data measured by a laser vibrometer.Finally,it is found that neither upside V-shaped channels nor channels with defects will affect the stable propagation of A_(0) Lamb waves along the proposed route.This proposed model and method are helpful in broadening the means of regulating elastic waves in phononic crystal structures,and extending practical application of topological edge states in such structures.
基金supported in part by the National Natural Science Foundation of China under Grant 52432012in part by the Shanghai Science and Technology Project with 25ZR1402508。
文摘The stator of the maglev track plays a crucial role in the operation of the maglev system.Currently,the efficiency of maglev track inspection is limited by several factors,including the large span of elevated structures,manual visual inspection,short inspection window times,and limited GPS positioning accuracy.To address these issues,this paper proposes a deep learning-based method for detecting and locating stator surface damage.This study establishes a maglev track stator surface image dataset,trains different object detection models,and compares their performance.Ultimately,YOLO and ByteTrack object tracking algorithms were chosen as the basic framework and enhanced to achieve automatic identification of high-speed maglev track stator surface damage images and track and count stator surface localization feature images.By matching the identified damaged images with their corresponding stator segment and beam segment sequence numbers,the location of the damage is pinpointed to the corresponding stator segment,enabling rapid and accurate identification and localization of complex damage to the maglev track stator surface.
基金supported by the State Key Program of the National Natural Science Foundation of China,No.82030035(to YES)Peak Disciplines(Type IV)of Institutions of Higher Learning in Shanghai(to LZ).
文摘The presence or absence of adult neural stem cells in the mammalian forebrain ependyma has been debated for two decades.In this study,we performed single-cell RNA sequencing to investigate the cellular composition of the ependymal surface of the adult mouse forebrain using whole mounts of lateral walls of lateral ventricles.We identified 12 different cell subtypes in the ependymal surface.Immunocytochemical analyses revealed that CD133^(+)multi-ciliated cells comprised 67.6%of ependymal cells,while the remaining 32.4%were CD133^(-).CD133^(+)ependymal cells can be further classified into FOXJ1^(+)/SOX2^(+)/ACTA2^(+)cells,FLT1^(+)/CD31^(+)/CLDN5^(+)endothelial-like cells,and PDGFRB^(+)/VTN^(+)/NG2^(+)pericyte-like cells,as well as endothelial-pericyte-like cells and Foxj1^(+)endothelial-like cells.CD133^(-)ependymal cells can be further divided into endothelial-like cells,Foxj1^(+)ependymal cells,Foxj1^(+)endothelial-like cells,pericyte-like cells,endothelial-pericyte-like cells,VIM^(+)cells,and cells negative for all of these markers.This comprehensive profiling confirms the heterogeneity of the ependymal surface in the adult mouse forebrain.Debate regarding whether adult ependymal cells contain neural stem cells has arisen because different researchers have examined different populations of ependymal cells.Our study provides a new perspective for investigation of clinical endogenous neural stem cells,ultimately paving the way for stem cell therapies in neurological diseases.
基金supported by the National Natural Science Foundation of China,Nos.82271419,81901902(to YZ),82202702(to ZW),82202351(to XH),82301550(to LYang),82271418(to XX)the Shanghai Rising-Star Program,No.22QA1408200(to YZ)the Fundamental Research Fundsfor the Central Universities,No.22120220555(to YZ).
文摘In the early stages of traumatic spinal cord injury,extensive accumulation of autophagosomes creates a neurotoxic microenvironment,exacerbating neuronal cell death and worsening tissue damage,ultimately hindering neurofunctional recovery.Activin A is a critical growth factor necessary for the development of the embryonic nervous system and for maintaining neuronal function in the adult cerebral cortex.It can inhibit excessive autophagy in ischemic stroke to reduce neuronal damage.However,the specific mechanism through which Activin A functions in the spinal cord remains poorly understood.In this study,we administered different concentrations of Activin A to neural stem cells from the spinal cord and found that Activin A stimulated the proliferation and neuronal differentiation of neural stem cells.Then,we established an in vitro oxidative stress model by using hydrogen peroxide to stimulate the neural stem cells-induced neurons.We found that Activin A could reduce apoptosis caused by oxidative stress.Subsequently,we treated a mouse model of spinal cord contusion with intrathecal injection of Activin A.Behavioral and electrophysiological results showed that Activin A promoted recovery of motor function and reconstruction of neural circuits in the model mice.Finally,RNA sequencing indicated that Activin A inhibited autophagy by activating the PI3K/AKT/mTOR pathway and upregulating the expression of synaptogenesis-related factor Sema3A in the spinal cord.These results suggest that Activin A may mediate the excessive autophagic response after spinal cord injury,promote the reconstruction of damaged neural circuits,and restore neurological function in the injured spinal cord.
文摘Inverse design of advanced materials represents a pivotal challenge in materials science.Leveraging the latent space of Variational Autoencoders(VAEs)for material optimization has emerged as a significant advancement in the field of material inverse design.However,VAEs are inherently prone to generating blurred images,posing challenges for precise inverse design and microstructure manufacturing.While increasing the dimensionality of the VAE latent space can mitigate reconstruction blurriness to some extent,it simultaneously imposes a substantial burden on target optimization due to an excessively high search space.To address these limitations,this study adopts a Variational Autoencoder guided Conditional Diffusion Generative Model(VAE-CDGM)framework integrated with Bayesian optimization to achieve the inverse design of composite materials with targeted mechanical properties.The VAE-CDGM model synergizes the strengths of VAEs and Denoising Diffusion Probabilistic Models(DDPM),enabling the generation of high-quality,sharp images while preserving a manipulable latent space.To accommodate varying dimensional requirements of the latent space,two optimization strategies are proposed.When the latent space dimensionality is excessively high,SHapley Additive exPlanations(SHAP)sensitivity analysis is employed to identify critical latent features for optimization within a reduced subspace.Conversely,direct optimization is performed in the low-dimensional latent space of VAE-CDGM when dimensionality is modest.The results demonstrate that both strategies accurately achieve the targeted design of composite materials while circumventing the blurred reconstruction flaws of VAEs,which offers a novel pathway for the precise design of advanced materials.
基金financial support from the Shanghai Science and Technology Committee(Grant no.24DZ3100504)the National Key Research and Development Program of China(Grant no.2022YFC2807102).
文摘Abstract To investigate the use of the three-point bending method and supplement the corresponding strength data of compacted snow for transportation-related applications in cold regions,compacted snow beams with an average density of 592 kg·m−3 were fabricated and tested at three distinct flexural strain rates.Each strain rate corresponded to the ductile,transitional,and brittle behavior of compacted snow,respectively.The flexural strength,ranging from 0.518 to 0.933 MPa,peaks at the ductile-to-brittle transition,while the flexural modulus,varying between 48.97 and 287.72 MPa,increases with strain rate within the tested range.At the same strain rate corresponding to brittle failure,both mechanical properties of compacted snow exhibit higher values than those of natural snow tested by the authors.Notably,the flexural strain rate at the ductile-to-brittle transition for compacted snow identified in this study is comparable to those previously reported for natural snow under uniaxial tension.Additionally,the obtained strength data are thoroughly compared with existing literature,with detailed discussions provided.The loading rates associated with typical failure modes of compacted snow under bending,together with the obtained strength values,provide methodological guidance and reference data for future in situ testing of compacted snow structures.
基金financedby the National Natural Science Foundation of China(Grant No.52090083)the Shanghai Rising-Star Program(Grant No.23QB1404800).
文摘Water-sand gushing(WSG)disasters in confinedaquifers pose significantchallenges to the utilization of deep underground spaces in soft soil areas.Since few studies have considered the impact of confined aquifer thickness and confinedwater pressure on WSG disasters,a novel visual model test system was developed to investigate the influencingcharacteristics and mechanisms of the two aforementioned factors.The test results showed that the WSG process in clay aquiclude-confinedaquifer composite strata exhibits two prominent stages.First,the sand loss zone expands vertically in an ellipsoid shape.Then,it expands horizontally once the ellipsoid reaches the boundary of the clay layer.The sand loss continues until the overlying clay sinks to the bottom to clog the gushing crack,creating a large sinkhole at the surface.Increasing the confinedaquifer thickness can increase the vertical expansion of the ellipsoid and delay the clay-clogging effects,thereby considerably increasing the severity of sand loss,stratum deformation,and surface settlement.An increase in the confinedwater pressure markedly increases the hydraulic gradient along the seepage path,which contributes to increasing the gushing rates of water and sand.As a result,substantial sand loss occurs before the clay clogs the gushing crack,inducing more cracks and deeper sinkholes at the surface.All the aforementioned results provide insights into the effects of confinedaquifer on WSG disasters in clay aquiclude-confinedaquifer composite strata.
基金supported by the National Key Research and Development Project(Grant No.2023YFE0110900)the National Natural Science Foundation of China(Grant Nos.42320104003,42477168).
文摘Underground hydrogen storage has gained interest in recent years due to the enormous demand for clean energy.Hydrogen is more diffusive than air,with a smaller density and lower viscosity.These unique properties introduce distinctive hydrodynamic phenomena in hydrogen storage,one of which is fingering.Fingering could induce the fluid trapped in small clusters of pores,leading to a dramatic decrease in hydrogen saturation and a lower recovery rate.In this study,numerical simulations are performed at the microscopic scale to understand the evolution of hydrogen saturation and the impacts of injection and withdrawal cycles.Two sets of micromodels with different porosity(0.362 and 0.426)and minimum sizes of pore throats(0.362 mm and 0.181 mm)are developed in the numerical model.A parameter analysis is then conducted to understand the influence of injection velocity(in the range of 10^(-2)m/s to 10^(-5)m/s)and porous structure on the fingering pattern,followed by an image analysis to capture the evolution of the fingering pattern.Viscous fingering,capillary fingering,and crossover fingering are observed and identified under different boundary conditions.The fractal dimension,specific area,mean angle,and entropy of fingers are proposed as geometric descriptors to characterize the shape of the fingering pattern.When porosity increases from 0.362 to 0.426,the saturation of hydrogen increases by 26.2%.Narrower pore throats elevate capillary resistance,which hinders fluid invasion.These results underscore the importance of pore structures and the interaction between viscous and capillary forces for hydrogen recovery efficiency.This work illuminates the influence of the pore structures and the fluid properties on the immiscible displacement of hydrogen and can be further extended to optimize the injection strategy of hydrogen in underground hydrogen storage.
