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Recent progress in nanomaterial-enhanced fluorescence polarization/anisotropy sensors 被引量:5
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作者 Jia Chen Juewen Liu +1 位作者 Xingguo Chen Hongdeng Qiu 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第9期1575-1580,共6页
As a promising signaling transduction approach, fluorescence polarization(FP)/fluorescence anisotropy(FA), provides a powerful quantitative tool for the rotational motion of fluorescently labeled molecules in chemical... As a promising signaling transduction approach, fluorescence polarization(FP)/fluorescence anisotropy(FA), provides a powerful quantitative tool for the rotational motion of fluorescently labeled molecules in chemical or biological homogeneous systems. Unlike fluorescence intensity, FP/FA is almost independent the concentration or quantum of fluorophores, but they are highly dependent on the size or molecular weight of the molecules or materials attached to fluorophores. Recently, significant progress in FP/FA was made, due to the introduction of some nanomaterials as FP/FA enhancers. The detection sensitivity is thus greatly improved by using nanomaterials as FP/FA enhancers, and nanomaterial-based FP/FA is currently used successfully in immunoassay, and analysis of protein, nucleic acid, small molecule and metal ion.Nanomaterial-based FP/FA provides a new kind of strategy to design fluorescent sensors and establishes innovative analytical methods. In this review, we summarize the scientific publications in the field of FP/FA sensor in recent five years, and first introduce the recent progress of FP/FA sensor based on nanomaterial. Subsequently, the various analytical applications of FP/FA based on nanomaterial are discussed. Finally, we provide perspectives on the current challenges and future prospects in this promising field. 展开更多
关键词 FLUORESCENCE polarization/anisotropy NANOMATERIALS Sensor RECENT progress Application
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One-pot synthesis of selenocarbamates from isocyanates and diselenides using the Zn/AlCl_3 system
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作者 Barahman Movassagh Mona Moradi 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第3期192-194,共3页
Several N-alkyl/aryl-Se-alkyl/(aryl)selenocarbamates were prepared from various isocyanates and diselenides by reductive cleavage of Se-Se bond with the Zn/AIC]3 system in dry acetonitrile at 80 ℃.
关键词 SelenocarbamatesDiselenideslsocyanatesZinc selenolateZn/AICI3 system
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Thrust characteristics of nano-carbon/Al/oxygenated salt nanothermites for micro-energetic applications
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作者 Ahmed Fahd Alex Baranovsky +3 位作者 Charles Dubois Jamal Chaouki Sherif Elbasuney Shady Shokry 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第12期55-69,共15页
Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozz... Combustion within small motors is key in the application-specific development of nanothermite-based micro-energetic systems. This study evaluates the performance of nanothermite mixtures in a converging-diverging nozzle and an open tube. Mixtures were prepared using nano-aluminum(n-Al),potassium perchlorate(KClO_(4)), and different carbon nanomaterials(CNMs) including graphene-oxide(GO), reduced GO, carbon nanotubes(CNTs) and nanofibers(CNFs). The mixtures were packed at different densities and ignited by laser beam. Performance was measured using thrust measurement,high-speed imaging, and computational fluid dynamics modeling, respectively. Thrust, specific impulse(ISP), volumetric impulse(ISV), as well as normalized energy were found to increase notably with CNM content. Two distinctive reaction regimes(fast and slow) were observed in combustion of low and high packing densities(20% and 55%TMD), respectively. Total impulse(IFT) and ISPwere maximized in the 5%GO/Al/KClO_4 mixture, producing 7.95 m N·s and 135.20 s respectively at 20%TMD, an improvement of 57%compared to a GO-free sample(5.05 m N·s and 85.88 s). CFD analysis of the motors over predicts the thrust generated but trends in nozzle layout and packing density agree with those observed experimentally;peak force was maximized by reducing packing density and using an open tube. The numerical force profiles fit better for the nozzle cases than the open tube scenarios due to the rapid nature of combustion. This study reveals the potential of GO in improving oxygenated salt-based nanothermites,and further demonstrates their applicability for micro-propulsion and micro-energetic applications. 展开更多
关键词 Nanothermites Graphene oxide Reduced graphene oxide Carbon nano material Oxygenated salts Laser ignition Computational fluid dynamics
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Synaptic and synchronic impairments in subcortical brain regions associated with early non-cognitive dysfunction in Alzheimer's disease
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作者 Nicolás Riffo-Lepe Juliana González-Sanmiguel +5 位作者 Lorena Armijo-Weingart Paulina Saavedra-Sieyes David Hernandez Gerson Ramos Loreto S.San Martín Luis G.Aguayo 《Neural Regeneration Research》 2026年第1期248-264,共17页
For many decades,Alzheimer's disease research has primarily focused on impairments within cortical and hippocampal regions,which are thought to be related to cognitive dysfunctions such as memory and language defi... For many decades,Alzheimer's disease research has primarily focused on impairments within cortical and hippocampal regions,which are thought to be related to cognitive dysfunctions such as memory and language deficits.The exact cause of Alzheimer's disease is still under debate,making it challenging to establish an effective therapy or early diagnosis.It is widely accepted that the accumulation of amyloid-beta peptide in the brain parenchyma leads to synaptic dysfunction,a critical step in Alzheimer's disease development.The traditional amyloid cascade model is initiated by accumulating extracellular amyloid-beta in brain areas essential for memory and language.However,while it is possible to reduce the presence of amyloid-beta plaques in the brain with newer immunotherapies,cognitive symptoms do not necessarily improve.Interestingly,recent studies support the notion that early alterations in subcortical brain regions also contribute to brain damage and precognitive decline in Alzheimer's disease.A body of recent evidence suggests that early Alzheimer's disease is associated with alterations(e.g.,motivation,anxiety,and motor impairment)in subcortical areas,such as the striatum and amygdala,in both human and animal models.Also,recent data indicate that intracellular amyloid-beta appears early in subcortical regions such as the nucleus accumbens,locus coeruleus,and raphe nucleus,even without extracellular amyloid plaques.The reported effects are mainly excitatory,increasing glutamatergic transmission and neuronal excitability.In agreement,data in Alzheimer's disease patients and animal models show an increase in neuronal synchronization that leads to electroencephalogram disturbances and epilepsy.The data indicate that early subcortical brain dysfunctions might be associated with non-cognitive symptoms such as anxiety,irritability,and motivation deficits,which precede memory loss and language alterations.Overall,the evidence reviewed suggests that subcortical brain regions could explain early dysfunctions and perhaps be targets for therapies to slow disease progression.Future research should focus on these non-traditional brain regions to reveal early pathological alterations and underlying mechanisms to advance our understanding of Alzheimer's disease beyond the traditionally studied hippocampal and cortical circuits. 展开更多
关键词 Alzheimer's disease AMPA receptors AMYGDALA epilepsy gamma-aminobutyric acid GLUTAMATE hippocampus NEURODEGENERATION neuronal excitability N-methyl-D-aspartate receptors non-cognitive nucleus accumbens
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Mechanical response and pore pressure evolution of cemented paste backfill under deep mine-like multiaxial stress and temperature conditions
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作者 Hongbin Liu Mamadou Fall 《International Journal of Mining Science and Technology》 2026年第2期457-474,共18页
As underground mining advances to greater depths,cemented paste backfill(CPB)is increasingly subjected to complex thermo-mechanical loading conditions,including multiaxial stress states and elevated temperatures.This ... As underground mining advances to greater depths,cemented paste backfill(CPB)is increasingly subjected to complex thermo-mechanical loading conditions,including multiaxial stress states and elevated temperatures.This study investigates the coupled effects of field-representative vertical self-weight and horizontal rockwall closure stresses,along with in-situ temperatures,on the mechanical behavior and pore water pressure(PWP)evolution of CPB.Experiments were conducted using a novel apparatus capable of controlling multiaxial stress and temperature during curing,replicating in-situ stress paths and thermal profiles typical of deep mine environments.Results show that multiaxial stress enhances CPB strength and stiffness by promoting denser particle packing,reducing porosity,and increasing frictional resistance.Elevated temperatures independently accelerate early-age cement hydration,further improving bond strength and stiffness.When combined,multiaxial stress and elevated temperature produce a synergistic enhancement in unconfined compressive strength(UCS)and elastic modulus,as confirmed by two-way ANOVA and synergy index analysis.PWP responses were also highly sensitive to thermo-mechanical conditions.The evolution of positive and negative PWP was governed by the interplay of thermal expansion,hydration-induced desaturation,and mechanical compaction.Multiaxial stress amplified early positive PWP and delayed its dissipation,whereas elevated temperature accelerated hydration and reduced pore pressure,leading to enhanced suction at later ages.A transient“stress-induced resaturation”effect was observed under late-stage excessive horizontal stress but was mitigated by elevated temperatures.These findings provide critical insights into the coupled mechanical and hydraulic behavior of CPB under realistic field conditions and offer guidance for optimizing backfill design,binder content,and barricade stability in deep mining applications. 展开更多
关键词 Cemented paste backfill TAILINGS Multiaxial stress Field temperature Mechanical properties Pore water pressure Rockwall closure
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Molecular Fingerprinting of Three Ex-Situ Cultivated Populations of Acalypha gaumeri Pax&K.Hoffm(Female and Male)and Evaluation of Their Antifungal Activity Against Phytopathogens
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作者 Christian Pérez-Chablé Daisy Pérez-Brito +3 位作者 Anuar Magaña-Alvarez Jairo Cristóbal-Alejo Irma L.Medina-Baizabal Marcela Gamboa-Angulo 《Phyton-International Journal of Experimental Botany》 2026年第2期36-54,共19页
Acalypha gaumeri(Euphorbiaceae)is the only endemic species of the genus in the Yucatan Peninsula.It is dioecious and has antifungal properties against various phytopathogens.In the present study,molecular identificati... Acalypha gaumeri(Euphorbiaceae)is the only endemic species of the genus in the Yucatan Peninsula.It is dioecious and has antifungal properties against various phytopathogens.In the present study,molecular identification of A.gaumeri was performed using the rbcL region,confirming its belonging to the Acalypha genus.Its genetic diversity was evaluated using 10 SPAR markers(ISSR and DAMD)from 60 individuals collected from female and male plants of the Kiuic,Tinum and Yaxcaba ex-situ populations.The results showed a high level of genetic polymorphism(PIC=0.980)and significant differences among the populations.Ethanol and aqueous extracts from leaves,stems,and roots of both genders and three populations were evaluated against three phytopathogenic fungi.Only the ethanol extracts of the roots showed inhibitory antifungal activity,whereas Kiuic and Tinum,both male and female individuals,showed inhibitory effects at 1000μg/mL against the three pathogens.The ethanol extract of the female flowering plant of Kiuic showed activity at minimum inhibitory concentrations of 250μg/mL against Alternaria chrysanthemi CICY004 and 500μg/mL against Colletotrichum gloeosporioides CICY002 and Penicillium oxalicum ITC25.Chromatographic profile of the ethanol extracts confirmed the presence of alkaloidal components in the ex-situ cultivated plants,which were analyzed by HPLC.The results revealed that the peaks at T_(R) of 7.60,7.88,and 8.49 min were the most abundant components(9.95%-21.93%),with differences between female and male plants of the three populations.This research confirms that A.gaumeri cultivated and genetically characterized is a potential raw material to develop an eco-friendly product for the control of fungal diseases in crops. 展开更多
关键词 Acalypha gaumeri antifungal activity alkaloidal compounds eco-friendly crop protection genetic diversity phytopathogenic fungi
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Spatio-Temporal Earthquake Analysis via Data Warehousing for Big Data-Driven Decision Systems
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作者 Georgia Garani George Pramantiotis Francisco Javier Moreno Arboleda 《Computers, Materials & Continua》 2026年第3期1963-1988,共26页
Earthquakes are highly destructive spatio-temporal phenomena whose analysis is essential for disaster preparedness and risk mitigation.Modern seismological research produces vast volumes of heterogeneous data from sei... Earthquakes are highly destructive spatio-temporal phenomena whose analysis is essential for disaster preparedness and risk mitigation.Modern seismological research produces vast volumes of heterogeneous data from seismic networks,satellite observations,and geospatial repositories,creating the need for scalable infrastructures capable of integrating and analyzing such data to support intelligent decision-making.Data warehousing technologies provide a robust foundation for this purpose;however,existing earthquake-oriented data warehouses remain limited,often relying on simplified schemas,domain-specific analytics,or cataloguing efforts.This paper presents the design and implementation of a spatio-temporal data warehouse for seismic activity.The framework integrates spatial and temporal dimensions in a unified schema and introduces a novel array-based approach for managing many-to-many relationships between facts and dimensions without intermediate bridge tables.A comparative evaluation against a conventional bridge-table schema demonstrates that the array-based design improves fact-centric query performance,while the bridge-table schema remains advantageous for dimension-centric queries.To reconcile these trade-offs,a hybrid schema is proposed that retains both representations,ensuring balanced efficiency across heterogeneous workloads.The proposed framework demonstrates how spatio-temporal data warehousing can address schema complexity,improve query performance,and support multidimensional visualization.In doing so,it provides a foundation for integrating seismic analysis into broader big data-driven intelligent decision systems for disaster resilience,risk mitigation,and emergency management. 展开更多
关键词 Data warehouse data analysis big data decision systems SEISMOLOGY data visualization
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Detection of Maliciously Disseminated Hate Speech in Spanish Using Fine-Tuning and In-Context Learning Techniques with Large Language Models
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作者 Tomás Bernal-Beltrán RonghaoPan +3 位作者 JoséAntonio García-Díaz María del Pilar Salas-Zárate Mario Andrés Paredes-Valverde Rafael Valencia-García 《Computers, Materials & Continua》 2026年第4期353-390,共38页
The malicious dissemination of hate speech via compromised accounts,automated bot networks and malware-driven social media campaigns has become a growing cybersecurity concern.Automatically detecting such content in S... The malicious dissemination of hate speech via compromised accounts,automated bot networks and malware-driven social media campaigns has become a growing cybersecurity concern.Automatically detecting such content in Spanish is challenging due to linguistic complexity and the scarcity of annotated resources.In this paper,we compare two predominant AI-based approaches for the forensic detection of malicious hate speech:(1)finetuning encoder-only models that have been trained in Spanish and(2)In-Context Learning techniques(Zero-and Few-Shot Learning)with large-scale language models.Our approach goes beyond binary classification,proposing a comprehensive,multidimensional evaluation that labels each text by:(1)type of speech,(2)recipient,(3)level of intensity(ordinal)and(4)targeted group(multi-label).Performance is evaluated using an annotated Spanish corpus,standard metrics such as precision,recall and F1-score and stability-oriented metrics to evaluate the stability of the transition from zero-shot to few-shot prompting(Zero-to-Few Shot Retention and Zero-to-Few Shot Gain)are applied.The results indicate that fine-tuned encoder-only models(notably MarIA and BETO variants)consistently deliver the strongest and most reliable performance:in our experiments their macro F1-scores lie roughly in the range of approximately 46%–66%depending on the task.Zero-shot approaches are much less stable and typically yield substantially lower performance(observed F1-scores range approximately 0%–39%),often producing invalid outputs in practice.Few-shot prompting(e.g.,Qwen 38B,Mistral 7B)generally improves stability and recall relative to pure zero-shot,bringing F1-scores into a moderate range of approximately 20%–51%but still falling short of fully fine-tuned models.These findings highlight the importance of supervised adaptation and discuss the potential of both paradigms as components in AI-powered cybersecurity and malware forensics systems designed to identify and mitigate coordinated online hate campaigns. 展开更多
关键词 Hate speech detection malicious communication campaigns AI-driven cybersecurity social media analytics large language models prompt-tuning fine-tuning in-context learning natural language processing
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Recent Advancements and Perspectives of Low-Dimensional Halide Perovskites for Visual Perception and Optoelectronic Applications
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作者 Humaira Rafique Ghulam Abbas +5 位作者 Manuel J.Mendes Pedro Barquinha Rodrigo Martins Elvira Fortunato Hugo Aguas Santanu Jana 《Nano-Micro Letters》 2026年第2期199-259,共61页
Low-dimensional(LD)halide perovskites have attracted considerable attention due to their distinctive structures and exceptional optoelectronic properties,including high absorption coefficients,extended charge carrier ... Low-dimensional(LD)halide perovskites have attracted considerable attention due to their distinctive structures and exceptional optoelectronic properties,including high absorption coefficients,extended charge carrier diffusion lengths,suppressed non-radiative recombination rates,and intense photoluminescence.A key advantage of LD perovskites is the tunability of their optical and electronic properties through the precise optimization of their structural arrangements and dimensionality.This review systematically examines recent progress in the synthesis and optoelectronic characterizations of LD perovskites,focusing on their structural,optical,and photophysical properties that underpin their versatility in diverse applications.The review further summarizes advancements in LD perovskite-based devices,including resistive memory,artificial synapses,photodetectors,light-emitting diodes,and solar cells.Finally,the challenges associated with stability,scalability,and integration,as well as future prospects,are discussed,emphasizing the potential of LD perovskites to drive breakthroughs in device efficiency and industrial applicability. 展开更多
关键词 Low-dimensional perovskites Light-emitting diodes PHOTODETECTORS PHOTOTRANSISTORS Photovoltaics
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Stochastic assessment of residual fatigue life of railway axles considering relevant critical factors
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作者 Dušan Tichoň Tomáš Vojtek +6 位作者 Pavol Dlhý Pavel Pokorný Luboš Náhlík Alfonso Fernández-Canteli Rostislav Fajkoš Ondřej Peter Pavel Hutař 《Railway Engineering Science》 2026年第1期1-24,共24页
Statistical distribution of residual fatigue life(RFL)of railway axles under given loading was computed using the Monte Carlo method by considering random variation of the selected input parameters.Experimental data f... Statistical distribution of residual fatigue life(RFL)of railway axles under given loading was computed using the Monte Carlo method by considering random variation of the selected input parameters.Experimental data for the EA4T railway axle steel,the loading spectrum,the press fit loading and the residual stress induced by surface hardening were considered in the crack propagation simulations.Usually,the material properties measured by tensile tests are considered to be the most informative source of material data.Under fatigue loading,however,the crack growth rates near the threshold are the most critical data.Two important influencing factors on these crack growth rates are presented:first,the air humidity and,second,the near-surface residual stress.The typical variation of these parameters in operation may change the RFL by one or two orders of magnitude.Experimentally obtained crack growth thresholds and residual stress profiles are highly affected by the used methodology.Therefore,the obtained input data may be located anywhere within a large scatter,while the experimenters are completely unaware of it.This can lead to dangerously non-conservative situations,e.g.when the thresholds are measured in a laboratory under humid air conditions and then applied to predictions of RFLs of axles operated in winter in low air humidity.This is significant for the topic of inspection interval optimisation.The results of experiments done on real 1:1 railway axles were close to the most frequent value found in the histogram of the numerically computed RFLs. 展开更多
关键词 Residual fatigue life Railway axles Fatigue crack Growth threshold Air humidity Monte Carlo method
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Exploring the influence of mixing energy on strength of sand treated by deep soil mixing
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作者 Mahdi Safdari Seh Gonbad Mahmood Reza Abdi 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期792-809,共18页
This study investigates the impacts of mixing time,execution procedure,cement dosage(α),and total water-to-cement ratio(W_(Total)/C)on the mixing energy(E)of deep soil mixing(DSM)columns and how E influences the stre... This study investigates the impacts of mixing time,execution procedure,cement dosage(α),and total water-to-cement ratio(W_(Total)/C)on the mixing energy(E)of deep soil mixing(DSM)columns and how E influences the strength of treated sand.Columns with a diameter of 7.5 cm were constructed using three mixing times(130,190,and 250 s),two execution procedures(normal and zigzag),threeαvalues(300,400,and 500 kg/m^(3)),and three W_(Total)/C ratios(2.5,3.0,and 3.5).For comparison,equivalent laboratory samples were also examined.Results revealed that increasing the mixing time andα,adopting the zigzag execution procedure,and reducing the W_(Total)/C ratio increase E.Outcomes indicated that an increase in E from 0.49-0.70 kJ to 0.70-0.90 kJ,0.90-1.10 kJ,and 1.10-1.40 kJ improves the unconfined compressive strength(UCS)of columns on average by 66%,124%,and 179%,respectively,and the secant modulus by 61%,110%,and 152%.Average strain at maximum stress also rises from 0.68%to 0.75%,0.81%,and 0.84%,respectively.The study identified a threshold in the direct relationship between E and the strength ratio(λ),beyond whichλdid not increase significantly with further increases in E.Additionally,at low and high E levels,DSM samples mainly failed by crushing and cracking modes,respectively.In DSM columns withα=500 kg/m^(3)and W_(Total)/C=2.5,increasing average E from 0.77 kJ to 0.95 kJ,1.08 kJ,and 1.28 kJ resulted in a reduction of coefficients of variation of UCS from 30.4%to 27.8%,24.5%,and 21.1%,respectively. 展开更多
关键词 Deep soil mixing(DSM) Mixing energy Unconfined compressive strength(UCS) Secant modulus Strain at maximum stress Failure mode Strength variability
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基于MobileNetV3的IGBT故障监测方法
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作者 肖凯文 钱欣辰 《智能城市》 2026年第1期84-88,共5页
绝缘栅双极型晶体管(IGBT)是电力行业变流器设备的主要器件,其健康状态影响电力设备和电力系统的安全稳定运行。为适应电力设备采用的嵌入式控制系统,文章提出基于MobileNetV3的IGBT故障监测方法。对IGBT的失效机理进行分析,进一步确定... 绝缘栅双极型晶体管(IGBT)是电力行业变流器设备的主要器件,其健康状态影响电力设备和电力系统的安全稳定运行。为适应电力设备采用的嵌入式控制系统,文章提出基于MobileNetV3的IGBT故障监测方法。对IGBT的失效机理进行分析,进一步确定能够表征IGBT运行状态的特征变化参数,将其作为算法模型的输入量;将MobileNetV3方法应用于IGBT故障监测,通过减小瓶颈模块中扩展层通道参数,对MobileNetV3进行进一步轻量化改进,构建MobileNetV3故障监测模型,以适应嵌入式系统的较小资源消耗实现高精度的故障监测;通过实验对所提故障监测方法的有效性进行验证。实验结果表明,优化后模型在保持95.98%准确率的同时,参数量降至896 676,内存占用仅为4.4 MB,在精度与资源消耗间取得了良好平衡。 展开更多
关键词 MobileNet IGBT 故障监测 深度学习
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Human cerebral organoids:Complex,versatile,and human-relevant models of neural development and brain diseases
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作者 Raquel Coronel Rosa González-Sastre +8 位作者 Patricia Mateos-Martínez Laura Maeso Elena Llorente-Beneyto Sabela Martín-Benito Viviana S.Costa Gagosian Leonardo Foti Ma Carmen González-Caballero Victoria López-Alonso Isabel Liste 《Neural Regeneration Research》 2026年第3期837-854,共18页
The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cereb... The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cerebral organoids have emerged as valuable tools offering a more complex,versatile,and human-relevant system than traditional animal models,which are often unable to replicate the intricate architecture and functionality of the human brain.Since human cerebral organoids are a state-of-the-art model for the study of neurodevelopment and different pathologies affecting the brain,this field is currently under constant development,and work in this area is abundant.In this review,we give a complete overview of human cerebral organoids technology,starting from the different types of protocols that exist to generate different human cerebral organoids.We continue with the use of brain organoids for the study of brain pathologies,highlighting neurodevelopmental,psychiatric,neurodegenerative,brain tumor,and infectious diseases.Because of the potential value of human cerebral organoids,we describe their use in transplantation,drug screening,and toxicology assays.We also discuss the technologies available to study cell diversity and physiological characteristics of organoids.Finally,we summarize the limitations that currently exist in the field,such as the development of vasculature and microglia,and highlight some of the novel approaches being pursued through bioengineering. 展开更多
关键词 assembloids BIOENGINEERING challenges disease modeling drug screening and toxicology human brain organoids human pluripotent stem cells neurodegenerative diseases NEURODEVELOPMENT VASCULARIZATION
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Advances in polymer-based hydrogel systems for adipose-derived mesenchymal stem cells toward bone regeneration
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作者 Nivetha Suresh Sundaravadhanan Lekhavadhani Nagarajan Selvamurugan 《World Journal of Orthopedics》 2026年第1期13-28,共16页
Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant i... Bone regeneration for non-load-bearing defects remains a significant clinical challenge requiring advanced biomaterials and cellular strategies.Adiposederived mesenchymal stem cells(AD-MSCs)have garnered significant interest in bone tissue engineering(BTE)because of their abundant availability,minimally invasive harvesting procedures,and robust differentiation potential into osteogenic lineages.Unlike bone marrow-derived mesenchymal stem cells,AD-MSCs can be easily obtained in large quantities,making them appealing alternatives for therapeutic applications.This review explores hydrogels containing polymers,such as chitosan,collagen,gelatin,and hyaluronic acid,and their composites,tailored for BTE,and emphasizes the importance of these hydrogels as scaffolds for the delivery of AD-MSCs.Various hydrogel fabrication techniques and biocompatibility assessments are discussed,along with innovative modifications to enhance osteogenesis.This review also briefly outlines AD-MSC isolation methods and advanced embedding techniques for precise cell placement,such as direct encapsulation and three-dimensional bioprinting.We discuss the mechanisms of bone regeneration in the AD-MSC-laden hydrogels,including osteoinduction,vascularization,and extracellular matrix remodeling.We also review the preclinical and clinical applications of AD-MSC-hydrogel systems,emphasizing their success and limitations.In this review,we provide a comprehensive overview of AD-MSC-based hydrogel systems to guide the development of effective therapies for bone regeneration. 展开更多
关键词 Mesenchymal stem cells Adipose-derived mesenchymal stem cells Bone tissue engineering HYDROGELS Bone regeneration POLYMERS
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Numerical Analysis and Geometric Assessment of Air Layer Distribution in a Ventilated Planing Hull in Calm Water
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作者 Massimiliano Chillemi Filippo Cucinotta Felice Sfravara 《哈尔滨工程大学学报(英文版)》 2026年第1期46-62,共17页
The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing ... The issue of resistance reduction through hull ventilation is of particular interest in contemporary research.This paper presents multiphase computational fluid dynamics(CFD)simulations with 2-DOF motion of a planing hull.The original hull was modified by introducing a step to allow air ventilation.Following an assessment of the hull performance,a simulation campaign in calm water was conducted to characterize the hull at various forward speeds and air insufflation rates for a defined single step geometry.Geometric analysis of the air layer thickness beneath the hull for each simulated condition was performed using a novel method for visualizing local air thickness.Additionally,two new parameters were introduced to understand the influence of spray rails on the air volume beneath the hull and to indicate the primary direction of ventilated air escape.A validation campaign and an assessment of uncertainty of the simulation has been conducted.The features offered by the CFD methodology include the evaluation of the air layer thickness as a function of hull velocity and injection flow rate and the air volume distribution beneath the hull.The air injection velocity can be adjusted across various operating conditions,thereby preventing performance or efficiency loss during navigation.Based on these findings,the study highlights the benefits of air insufflation in reducing hull resistance for high-speed planing vessels.This work lays a robust foundation for future research and new promising topics,as the exploration of air insufflation continues to be a topic of contemporary interest within naval architecture and hydrodynamics. 展开更多
关键词 Computational fluid dynamics Air cavity ships Planing hull HYDRODYNAMICS Maritime sustainability
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Molecular hydrogen therapy in musculoskeletal conditions:An evidence-based review and critical analysis
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作者 Naveen Jeyaraman Madhan Jeyaraman +3 位作者 Swaminathan Ramasubramanian Shrideavi Murugan Arulkumar Nallakumarasamy Sathish Muthu 《World Journal of Orthopedics》 2026年第1期40-56,共17页
Molecular hydrogen(H2)demonstrates selective antioxidant and anti-inflammatory properties with therapeutic potential across musculoskeletal conditions including osteoarthritis,rheumatoid arthritis,exercise-induced mus... Molecular hydrogen(H2)demonstrates selective antioxidant and anti-inflammatory properties with therapeutic potential across musculoskeletal conditions including osteoarthritis,rheumatoid arthritis,exercise-induced muscle damage,chronic pain syndromes,tendinopathies,and muscle atrophy.This review critically evaluates preclinical and clinical evidence for H2 therapy and identifies research gaps.A comprehensive search of PubMed,EMBASE,and Cochrane Library(up to April 2025)yielded 45 eligible studies:25 preclinical and 20 clinical trials.Preclinical models consistently showed reductions in reactive oxygen species,inflammatory cytokines,and improved cell viability.Clinical trials reported symptomatic relief in osteoarthritis,decreased Disease Activity Score 28 in rheumatoid arthritis,and accelerated clearance of muscle damage markers.Delivery methods varied-hydrogen-rich water,gas inhalation,and saline infusion-hindering direct comparison.Mechanistic biomarkers were inconsistently reported,limiting understanding of target engagement.Common limitations included small sample sizes,short durations,and protocol heterogeneity.Despite these constraints,findings suggest H2 may serve as a promising adjunctive therapy via antioxidant,anti-inflammatory,and cytoprotective mechanisms.Future research should prioritize standardized delivery protocols,robust mechanistic endpoints,and longer-term randomized trials to validate clinical efficacy and optimize therapeutic strategies. 展开更多
关键词 Molecular hydrogen Musculoskeletal disorders Oxidative stress ANTI-INFLAMMATION Clinical evidence
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Divergent vegetation response to increasing grazing pressure in arid and semi-arid rangelands in Argentina
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作者 Dianela Alejandra CALVO Juan José GAITÁN +2 位作者 Juan Manuel ZEBERIO Ana Isabel CASALINI Guadalupe PETER 《Journal of Arid Land》 2026年第1期84-100,共17页
The connection between climatic factors and grazing is essential for maintaining ecosystem function and vegetation productivity.This study examined the impact of grazing intensity on vegetation across a broad climatic... The connection between climatic factors and grazing is essential for maintaining ecosystem function and vegetation productivity.This study examined the impact of grazing intensity on vegetation across a broad climatic gradient spanning the Espinal,Argentine Low Monte,and Patagonian Steppe ecoregions of Argentina.The research was carried out at eight sampling sites with radial grazing gradients generated around artificial water sources(piospheres),exhibiting two contrasting response patterns of vegetation to grazing pressure.One of the response patterns shows a typical vegetation response to grazing that the vegetation productivity increases with the distance to the water sources(decreasing grazing intensity).The second pattern is found in drier regions,where vegetation presents an inverse productivity response that vegetation productivity is higher near water sources(high grazing intensity)due to increased shrub cover.Vegetation productivity was measured using the Normalized Difference Vegetation Index(NDVI).Vegetation patch structure and cover were determined for each site with high,medium,and low grazing intensities.Results indicated that shrub cover is the primary driver of vegetation productivity,showing contrasting responses to grazing intensity between the two identified patterns.While NDVI proved to be a reliable proxy for shrub cover and total vegetation cover(R2>0.70),it failed to reflect grass cover dynamics.Furthermore,mean annual temperature was more strongly correlated with vegetation cover changes,while grazing intensity significantly altered vegetation patch structure and soil cover distribution.Specifically,in drier regions,high grazing intensity led to larger patches while,in wetter regions,it led to smaller patches(fragmentation).Shrubs,with their deeper roots and drought tolerance,were less preferred and more resistant to grazing in arid environments and thrived under grazing pressure in these arid conditions.Our results underscored the need for adaptive management strategies in grazing systems.Traditional approaches may require significant adjustments,as the efficacy of management hinges on the interplay of specific climatic conditions and the varied responses of vegetation.Furthermore,effective conservation efforts should prioritize the recognition and protection of shrubs given their critical contribution to ecosystem function and biodiversity.Ultimately,this research provides a valuable framework to understand the complex dynamics between grazing and vegetation in arid and semi-arid environments,highlighting that sustainable grazing practices should be tailored to account for both climatic variables and the unique characteristics of different plant communities. 展开更多
关键词 grazing intensity vegetation productivity piospheres shrub encroachment climate change Patagonian Steppe
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An Improved PID Controller Based on Artificial Neural Networks for Cathodic Protection of Steel in Chlorinated Media
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作者 JoséArturo Ramírez-Fernández Henevith G.Méndez-Figueroa +3 位作者 Sebastián Ossandón Ricardo Galván-Martínez MiguelÁngel Hernández-Pérez Ricardo Orozco-Cruz 《Computers, Materials & Continua》 2026年第3期624-640,共17页
In this study,artificial neural networks(ANNs)were implemented to determine design parameters for an impressed current cathodic protection(ICCP)prototype.An ASTM A36 steel plate was tested in 3.5%NaCl solution,seawate... In this study,artificial neural networks(ANNs)were implemented to determine design parameters for an impressed current cathodic protection(ICCP)prototype.An ASTM A36 steel plate was tested in 3.5%NaCl solution,seawater,and NS4 using electrochemical impedance spectroscopy(EIS)to monitor the evolution of the substrate surface,which affects the current required to reach the protection potential(Eprot).Experimental data were collected as training datasets and analyzed using statistical methods,including box plots and correlation matrices.Subsequently,ANNs were applied to predict the current demand at different exposure times,enabling the estimation of electrochemical parameters(limiting voltage values)that can be used to optimize a self-regulating ICCP system.The obtained electrochemical parameters were then used,through Particle Swarm Optimization(PSO),to fine-tune an ANN-based proportional-integral-derivative(PID)controller for the ICCP system. 展开更多
关键词 Artificial neural networks(ANNs) corrosion impressed current cathodic protection(ICCP) proportional integral derivative(PID)corrosion control particle swarm optimization(PSO) statistical analysis
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Synaptic mitochondria in aging and neurodegenerative diseases:Functional decline and vulnerability
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作者 Karina A.Cicali Angie K.Torres Cheril Tapia-Rojas 《Neural Regeneration Research》 2026年第6期2145-2152,共8页
Aging is a physiological and complex process produced by accumulative age-dependent cellular damage,which significantly impacts brain regions like the hippocampus,an essential region involved in memory and learning.A ... Aging is a physiological and complex process produced by accumulative age-dependent cellular damage,which significantly impacts brain regions like the hippocampus,an essential region involved in memory and learning.A crucial factor contributing to this decline is the dysfunction of mitochondria,particularly those located at synapses.Synaptic mitochondria are specialized organelles that produce the energy required for synaptic transmission but are also important for calcium homeostasis at these sites.In contrast,non-synaptic mitochondria primarily involve cellular metabolism and long-term energy supply.Both pools of mitochondria differ in their form,proteome,functionality,and cellular role.The proper functioning of synaptic mitochondria depends on processes such as mitochondrial dynamics,transport,and quality control.However,synaptic mitochondria are particularly vulnerable to age-associated damage,characterized by oxidative stress,impaired energy production,and calcium dysregulation.These changes compromise synaptic transmission,reducing synaptic activity and cognitive decline during aging.In the context of neurodegenerative diseases such as Alzheimer’s,Parkinson’s,and Huntington’s,the decline of synaptic mitochondrial function is even more pronounced.These diseases are marked by pathological protein accumulation,disrupted mitochondrial dynamics,and heightened oxidative stress,accelerating synaptic dysfunction and neuronal loss.Due to their specialized role and location,synaptic mitochondria are among the first organelles to exhibit dysfunction,underscoring their critical role in disease progression.This review delves into the main differences at structural and functional levels between synaptic and non-synaptic mitochondria,emphasizing the vulnerability of synaptic mitochondria to the aging process and neurodegeneration.These approaches highlight the potential of targeting synaptic mitochondria to mitigate age-associated cognitive impairment and synaptic degeneration.This review emphasizes the distinct vulnerabilities of hippocampal synaptic mitochondria,highlighting their essential role in sustaining brain function throughout life and their promise as therapeutic targets for safeguarding the cognitive capacities of people of advanced age. 展开更多
关键词 AGING HIPPOCAMPUS MEMORY MITOCHONDRIA synaptic mitochondria
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Bacterial extracellular vesicles in the brain:Pathological effects and therapeutic possibilities
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作者 Yaiza M.Arenas Paula Izquierdo-Altarejos +2 位作者 Gaspar Pérez-Martínez Vicente Felipo Marta Llansola 《Neural Regeneration Research》 2026年第6期2101-2109,共9页
The mechanisms leading to neurological and neurodegenerative diseases are not completely known,and new,more effective,therapeutic treatments are necessary for most neurological pathologies.The treatment of neurologica... The mechanisms leading to neurological and neurodegenerative diseases are not completely known,and new,more effective,therapeutic treatments are necessary for most neurological pathologies.The treatment of neurological and neurodegenerative diseases is complicated due to the blood-brain barrier,which makes it difficult for drugs to access the brain areas in which they must act to improve the pathology.A tool that can help to overcome this difficulty is the use of extracellular vesicles,which can easily cross the blood-brain barrier.The extracellular vesicles are considered a main way of communication between the brain and the rest of the body,with important implications for the physiopathology and therapy of neurological diseases.In recent years,the involvement of microbiota in many neurological pathologies,as well as its possible therapeutic role,has also become evident.A key mediator in the pathologic and beneficial effects of microbiota seems to be the bacterial extracellular vesicles.There is an important communication between the brain and the intestinal microbiota(the gut-brain axis),by which the microbiota influences brain function,impacts on mental health,and plays a role in different neurological and neurodegenerative diseases.The identification of the mechanisms involved in this gut-brain axis is essential to understanding the mechanisms of neurological pathologies and to developing more effective treatments for these diseases.Bacterial extracellular vesicles would play a relevant role in these processes.This review compiles the recent information and evidence on the role of bacterial extracellular vesicles in brain pathologies and on the therapeutic utility of bacterial extracellular vesicles in neurological and neurodegenerative diseases.One advantage of bacterial extracellular vesicles compared to extracellular vesicles derived from other cell types,such as stem cells,is that bacterial extracellular vesicles are generally easier to produce and modify.Bacterial extracellular vesicles may be easily modified to target a specific pathology and/or to enhance its therapeutic efficacy.Although the studies are still scarce,they open a wide field of possibilities for future studies,which will lead to a deeper understanding of the role of microbiota and bacterial extracellular vesicles in neurological pathologies and the underlying mechanisms,as well as to the development of new treatments based on the use of bacterial extracellular vesicles in neurological diseases. 展开更多
关键词 bacteria bacterial extracellular vesicles gut-brain axis inflammation microbiota NEUROINFLAMMATION neurological diseases NEUROTRANSMISSION PATHOGENIC probiotic therapeutic treatment
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