Secondary injury following spinal cord injury is primarily characterized by a complex inflammatory response,with resident microglia and infiltrating macrophages playing pivotal roles.While previous studies have groupe...Secondary injury following spinal cord injury is primarily characterized by a complex inflammatory response,with resident microglia and infiltrating macrophages playing pivotal roles.While previous studies have grouped these two cell types together based on similarities in structure and function,an increasing number of studies have demonstrated that microglia and macrophages exhibit differences in structure and function and have different effects on disease processes.In this study,we used single-cell RNA sequencing and spatial transcriptomics to identify the distinct evolutionary paths of microglia and macrophages following spinal cord injury.Our results showed that microglia were activated to a pro-inflammatory phenotype immediately after spinal cord injury,gradually transforming to an anti-inflammatory steady state phenotype as the disease progressed.Regarding macrophages,our findings highlighted abundant communication with other cells,including fibroblasts and neurons.Both pro-inflammatory and neuroprotective effects of macrophages were also identified;the pro-inflammatory effect may be related to integrin β2(Itgb2) and the neuroprotective effect may be related to the oncostatin M pathway.These findings were validated by in vivo experiments.This research underscores differences in the cellular dynamics of microglia and macrophages following spinal cord injury,and may offer new perspectives on inflammatory mechanisms and potential therapeutic targets.展开更多
Fuel cell electric vehicles hold great promise for a diverse range of applications in reducing greenhouse gas emissions.In power fuel cell systems,hydrogen fuel serves as an energy vector.To ensure its suitability,it ...Fuel cell electric vehicles hold great promise for a diverse range of applications in reducing greenhouse gas emissions.In power fuel cell systems,hydrogen fuel serves as an energy vector.To ensure its suitability,it is necessary for the quality of hydrogen to adhere to the standards set by ISO 14687:2019,which sets maximum limits for 14 impurities in hydrogen,aiming to prevent any degradation of fuel cell performance.Ammonia(NH_(3))is a prominent pollutant in fuel cells,and accurate measurements of its concentration are crucial for hydrogen fuel cell quantity.In this study,a novel detection platform was developed for determining NH_(3)in real hydrogen samples.The online analysis platform integrates a self-developed online dilution module with a Fourier transform infrared spectrometer(ODM-FTIR).The ODM-FTIR can be operated fully automatically with remote operation.Under the optimum conditions,this method achieved a wide linear range between(50∼1000)nmol/mol.The limit of detection(LOD)was as low as 2 nmol/mol with a relative standard deviation(RSD,n=7)of 3.6%at a content of 50 nmol/mol.To ensure that the quality of the hydrogen products meets the requirement of proton exchange membrane fuel cell vehicles(PEMFCV),the developed ODM-FTIR system was applied to monitor the NH_(3)content in Chengdu Hydrogen Energy Co.,Ltd.for 21 days during Chengdu 2021 FISU World University Games.The proposed method retains several unique advantages,including a low detection limit,excellent repeatability,high accuracy,high speed,good stability,and calibration flexibility.It is an effective analytical method for accurately quantifying NH_(3)in hydrogen,especially suitable for online analysis.It also provides a new idea for the analysis of other impurity components in hydrogen.展开更多
Cardiovascular disease(CVD)is a major global health challenge,which causes significant illness and death worldwide.These include a range of conditions that affect the heart and blood vessels,including coro-nary artery...Cardiovascular disease(CVD)is a major global health challenge,which causes significant illness and death worldwide.These include a range of conditions that affect the heart and blood vessels,including coro-nary artery disease,stroke,peripheral artery disease,and heart failure.Despite advances in medicine and healthcare delivery,CVD continues to have a serious impact on individuals,families,and the healthcare system.This review begins by delineating the merits and demerits of commonly employed synthetic and natural materials for artificial blood vessels.It delves into various techniques commonly employed in the fabrication of artificial blood vessels,encompassing advanced textile technologies,electrospinning,ther-mally induced phase separation,and 3D printing.The review critically analyzes the attributes of different preparation methodologies alongside the latest advancements in research.The review also outlines the requisite performance requirements for artificial blood vessels,which encompass robust mechanical prop-erties,appropriate porosity,exceptional compatibility,and antibacterial attributes.It provides a succinct overview of ongoing effort s in vascular functionalization,particularly emphasizing thrombus mitigation,promotion of endothelialization,and enhancement of nitric oxide production.The review finally encap-sulates the primary challenges confronting vascular grafts and prospective avenues for future research.展开更多
Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-e...Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction.However,the mechanisms involved remain unclear.In this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming phenotypes.The expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury.In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between them.We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway.This,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways.In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function recovery.Overall,Gas6 may play a role in the treatment of spinal cord injury.It can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.展开更多
Background:This study investigated the relationship between meteorological factors and daily outpatient visits to rabies post-exposure prophylaxis clinics to inform animal injury prevention strategies.Methods:Daily ou...Background:This study investigated the relationship between meteorological factors and daily outpatient visits to rabies post-exposure prophylaxis clinics to inform animal injury prevention strategies.Methods:Daily outpatient visit data from rabies post-exposure prophylaxis clinics in Jinan and corresponding meteorological data were collected from January 1,2020,to December 31,2022.A generalized additive model was used to quantitatively assess the relationship between these factors.A total of 202,010 patients visited these clinics during this period.Results:Daily mean,maximum,and minimum temperatures,and relative humidity were positively associated with outpatient visits.A 1°C increase in mean,maximum,and minimum temperatures corresponded to increases in daily visits of 1.65%(95%Confidence Interval(CI):1.55–1.76),1.59%(95%CI:1.50–1.69),and 1.27%(95%CI:1.17–1.36)respectively.Each 1%increase in relative humidity was associated with a 0.18%(95%CI:0.15–0.20)increase in visits.Mean pressure was negatively associated with outpatient visits,the outpatient visits decreased by 0.91%(95%CI:−1.71 to−0.11)for every 1 kPa increased in mean pressure.Conclusion:The change of meteorological factors will lead to the increase of outpatient visits in rabies exposure treatment clinic.展开更多
The two-dimensional electron gas(2DEG)formed at the interface between two oxide insulators provides new opportunities for electronics and spintronics.The broken inversion symmetry at the heterointerface results in a R...The two-dimensional electron gas(2DEG)formed at the interface between two oxide insulators provides new opportunities for electronics and spintronics.The broken inversion symmetry at the heterointerface results in a Rashba spin-orbit coupling(RSOC)effect that enables the conversion between spin and charge currents.However,conducting oxide interfaces that simultaneously exhibit strong RSOC and high carrier mobility-a combination query for achieving high spin-to-charge inter-conversion efficiencies-remain scarce.Herein,we report a correlated 2DEG with giant Rashba splitting and high electron mobility in(111)-oriented EuTiO_(3)/KTaO_(3)(ETO/KTO)heterostructures under light illumination.Upon light modulation,a unique carrier-dependent giant anomalous Hall effect,the signature of spin-polarized 2DEG,emerges with a sign crossover at a carrier density of approximately 5.0×10^(13)cm^(-2),highlighting dramatic changes in the band topology of KTO(111)interface.Furthermore,at 2 K,the carrier mobility is enhanced from 103 cm^(2)·V^(-1)·s^(-1)to 1800 cm^(2)·V^(-1)·s^(-1),a remarkable enhancement of approximately 20 times.Accompanying with a giant Rashba coefficient αR up to 360meV·˚A,this high mobility ferromagnetic 5d oxide 2DEG is predicted to achieve a giant spin-to-charge conversion efficiency ofλ~10 nm,showing great potential for designing low-power spin-orbitronic devices.展开更多
The X(3872)is theoretically predicted to have a spin-0 partner state denoted as X_(0).Assuming the X_(0)as a molecular bound state,we calculate the decay widths of X_(0)→VV and X_(0)→PP(V and P stand for light vecto...The X(3872)is theoretically predicted to have a spin-0 partner state denoted as X_(0).Assuming the X_(0)as a molecular bound state,we calculate the decay widths of X_(0)→VV and X_(0)→PP(V and P stand for light vector and pseudoscalar mesons,respectively)via intermediate charmed meson loops.Three different configurations of the X_(0),i.e.,pure neutral components(θ=0),isospin singlet(θ=π/4),and pure charged components(θ=π/2),are investigated.Within a commonly accepted range of the model parameterα,the predicted decay widths of X_(0)→VV are on the order of a few hundred keV,while the decay widths of X_(0)→PP can reach several MeV.The X_(0)→ρρandππhave larger decay rates.The relative width ratios between the channels are nearly model-independent.Moreover,among those channels only with isovector or isoscalar mesons,the relevant ratios are also independent of the phase angle.The predicted ratios are helpful for searching the X_(0)in the future experiments at BESIII and Belle II.展开更多
Radial growth of trees is highly sensitive to environmental changes,but the effect of climate on tree rings in Qinghai spruce(Picea crassifolia),a widely distributed endemic conifer in western China,is more complex th...Radial growth of trees is highly sensitive to environmental changes,but the effect of climate on tree rings in Qinghai spruce(Picea crassifolia),a widely distributed endemic conifer in western China,is more complex than in many other conifers.A comprehensive understanding of the spatiotemporal climatic responses of its rings is needed to develop theoretical basis for designing strategies for its conservation and management.Here,our synthesis of the literature on responses of radial growth of Qinghai spruce to monthly climate variables in different environmental conditions by meta-analysis showed that precipitation and drought severity are the main limiting factors for Qinghai spruce radial growth in the semiarid region of northwestern China.In warmer and drier areas,radial growth of Qinghai spruce is mainly limited by drought.In the areas north of the 600-mm annual precipitation isoline,the tree-ring width(TRW)was significantly positively correlated with precipitation and significantly negatively correlated with temperature during the growing season(June-August).The limiting effect of drought on Qinghai spruce is also gradually increasing from southeast to northwest,to the west of 103°E and within 37°N-39°N.展开更多
BACKGROUND Insomnia is a common sleep disorder that negatively impacts quality of life and is frequently comorbid with depression and anxiety.Chronic insomnia affects approximately 15%of the global population,with hig...BACKGROUND Insomnia is a common sleep disorder that negatively impacts quality of life and is frequently comorbid with depression and anxiety.Chronic insomnia affects approximately 15%of the global population,with higher prevalence among females and the elderly.While existing research suggests a bidirectional relationship between insomnia and emotional disorders,the specific impact of insomnia severity on depression,anxiety,and quality of life remains unclear.This study investigates the correlation between insomnia severity and these factors in psychiatric outpatients,hypothesizing that greater insomnia severity is associated with higher levels of depression and anxiety,as well as poorer quality of life.AIM To explore the correlation between insomnia severity and depression,anxiety,and quality of life in primary chronic insomnia patients.METHODS From June to December 2023,345 patients with primary insomnia in Chifeng city were recruited and divided into three groups based on Pittsburgh sleep quality index(PSQI)scores:Mild(n=137),moderate(n=162),and severe(n=46).Demographic data were collected via questionnaires.Self-rating depression scale(SDS),self-rating anxiety scale(SAS),PSQI,and short form 36(SF-36)scores were compared,and Pearson and partial correlation analyses were performed.RESULTS The greater the degree of insomnia,the greater the symptoms of depression and anxiety(P<0.001).The more severe the insomnia,the lower the SF-36 score(excluding body pain),and the difference between the three groups was statist ically significant(P<0.001).Pearson correlation analysis and partial correlation analysis depicted the SDS score and SAS score were apparently positively correlated with the severity of insomnia(P<0.001).Pearson correlation analysis and partial correlation analysis depicted the SF-36 scores were apparently positively correlated with the severity of insomnia(P<0.05).CONCLUSION Depression and anxiety are independent factors influencing insomnia severity in primary chronic insomnia patients.Higher depression/anxiety levels correlate with worse insomnia,impacting quality of life.展开更多
Semitransparent organic photovoltaics(ST-OPVs)for building integration represent a pivotal direction in the development of photovoltaic industry.Solution-processed silver nanowires(AgNWs)are considered promising candi...Semitransparent organic photovoltaics(ST-OPVs)for building integration represent a pivotal direction in the development of photovoltaic industry.Solution-processed silver nanowires(AgNWs)are considered promising candidates for transparent electrodes in semitransparent devices due to their high transparency-conductivity-efficiency merit,large-scale processability,and low cost.In this work,we develop two solution-processed organic–inorganic hybrid electrodes,named AgNWs-PD and AgNWsPC,utilizing AgNWs as the conductive framework and aliphatic amine-functionalized perylene-diimide(PDINN)as the sandwiched material,while AgNWs-PC exhibits significantly improved electrical conductivity and enhanced contact area with the underlying electron transport layer.The optimized device achieves a power conversion efficiency of 9.45%with an open circuit voltage of 0.846 V,a high filling factor of 75.4%,and an average visible transmittance(AVT)of 44.0%,delivering an outstanding light utilization efficiency(LUE)of 4.16%,which is the highest reported value for all solution-processed ST-OPVs.In addition,by coupling a 30-nm tellurium dioxide atop AgNWs-PC,the bifaciality factor of derivative devices improves from 73.7%to 99.4%,while maintaining a high bifacial LUE over 3.7%.Our results emphasize the superiority and effectiveness of PDINN-sandwiched AgNWs electrodes for highperformance and all solution-processed ST-OPVs.展开更多
It is highly challenging to precisely compare the impacts of anthropogenic pollutants on the photooxidation of isomeric volatile organic compounds with respect to molecular compositions and particle number/mass concen...It is highly challenging to precisely compare the impacts of anthropogenic pollutants on the photooxidation of isomeric volatile organic compounds with respect to molecular compositions and particle number/mass concentrations of secondary organic aerosols(SOAs).In this study,we conducted a series of well-defined indoor chamber experiments to compare the effects of NO_(x)(NO and NO_(2))on the photooxidation of isomeric monoterpenes ofβ-pinene and limonene.For the photooxidation ofβ-pinene with NO_(x),the increase of the initial concentrations of NO([NO]_(0))shows a monotonous suppression of the particle mass concentration,whereas the increase of[NO_(2)]_(0) shows a monotonous enhancement of the particle mass concentration.For the photooxidation of limonene with NO_(x),the increase of[NO]_(0) exhibits a monotonous suppression of the particle mass concentration,whereas the increase of[NO_(2)]_(0) shows a parabolic trend of the particle mass concentration.Utilizing a newly developed vacuum ultraviolet free electron laser(VUV-FEL),the online threshold photoionization mass spectrometry reveals a series of novel compounds at molecular weight(MW)=232 and 306 for theβ-pinene+NO_(x) system and MW=187,261,280,and 306 for the limonene+NO_(x) system.The molecular structures and formation pathways of these species were inferred,which led to the prediction of the diversity and difference of SOA products(i.e.,ester and peroxide accretion products)formed from different monoterpene precursors.To improve the predictions of future air quality,it is recommended that climate models should incorporate the NO_(x)-driven diurnal photooxidation of monoterpenes for SOA formation mechanisms.展开更多
In recent years,the country has spent significant workforce and material resources to prevent traffic accidents,particularly those caused by fatigued driving.The current studies mainly concentrate on driver physiologi...In recent years,the country has spent significant workforce and material resources to prevent traffic accidents,particularly those caused by fatigued driving.The current studies mainly concentrate on driver physiological signals,driving behavior,and vehicle information.However,most of the approaches are computationally intensive and inconvenient for real-time detection.Therefore,this paper designs a network that combines precision,speed and lightweight and proposes an algorithm for facial fatigue detection based on multi-feature fusion.Specifically,the face detection model takes YOLOv8(You Only Look Once version 8)as the basic framework,and replaces its backbone network with MobileNetv3.To focus on the significant regions in the image,CPCA(Channel Prior Convolution Attention)is adopted to enhance the network’s capacity for feature extraction.Meanwhile,the network training phase employs the Focal-EIOU(Focal and Efficient Intersection Over Union)loss function,which makes the network lightweight and increases the accuracy of target detection.Ultimately,the Dlib toolkit was employed to annotate 68 facial feature points.This study established an evaluation metric for facial fatigue and developed a novel fatigue detection algorithm to assess the driver’s condition.A series of comparative experiments were carried out on the self-built dataset.The suggested method’s mAP(mean Average Precision)values for object detection and fatigue detection are 96.71%and 95.75%,respectively,as well as the detection speed is 47 FPS(Frames Per Second).This method can balance the contradiction between computational complexity and model accuracy.Furthermore,it can be transplanted to NVIDIA Jetson Orin NX and quickly detect the driver’s state while maintaining a high degree of accuracy.It contributes to the development of automobile safety systems and reduces the occurrence of traffic accidents.展开更多
Intelligent Automation&Soft Computing has retracted the article titled“Line Trace Effective Comparison AlgorithmBased onWavelet Domain DTW”[1],Intell Automat Soft Comput.2019;25(2):359–366 at the request of the...Intelligent Automation&Soft Computing has retracted the article titled“Line Trace Effective Comparison AlgorithmBased onWavelet Domain DTW”[1],Intell Automat Soft Comput.2019;25(2):359–366 at the request of the authors.DOI:10.31209/2019.100000097 URL:https://www.techscience.com/iasc/v25n2/39663 The article duplicates significant parts of a paper published in Journal of Intelligent&Fuzzy Systems[2].展开更多
In order to restrain the huge volume expansion of bismuth(Bi)anodes in sodium ion batteries(SIBs),the core-shell structure Bi@mesoporous carbon nanospheres(Bi@mC)composite was designed and prepared by sol-gel method c...In order to restrain the huge volume expansion of bismuth(Bi)anodes in sodium ion batteries(SIBs),the core-shell structure Bi@mesoporous carbon nanospheres(Bi@mC)composite was designed and prepared by sol-gel method coupled heat treatment.Structural characterization displays that the average diameter of the as-prepared Bi@mC composites is about 200 nm and thickness of the N-doped mesoporous carbon shells is 20-30 nm.Electrochemical test and kinetic analysis results show that the mesoporous carbon shell can not only effectively relieve the stress caused by volume expansion of Bi and protect active material from pulverization caused by the stress during charging/discharging process,but also facilitate quick diffusion of sodium ions,thus improving rate and cycling performance.Bi@mC delivers a high specific capacity of 279 mA·h/g and a capacity retention of 97.6%after 3500 cycles at a current density of 5 A/g.Even at a high current density of 20 A/g,Bi@mC can still maintain a high specific capacity of 266 mA·h/g.Additionally,the Bi@mC//NVP full button sodium-ion batteries(SIBs)assembled using Bi@mC anode and Na_(3)V_(2)(PO_(4))_(3)(NVP)cathode deliver an energy density of 182 W·h/kg.展开更多
BACKGROUND Occult pancreaticobiliary reflux(OPBR)is characterized by the absence of congenital anomalies at the pancreaticobiliary junction yet leads to altered bile composition and an increased incidence of gallbladd...BACKGROUND Occult pancreaticobiliary reflux(OPBR)is characterized by the absence of congenital anomalies at the pancreaticobiliary junction yet leads to altered bile composition and an increased incidence of gallbladder stones.AIM To explore the computed tomography(CT)imaging characteristics of gallbladder stones in patients diagnosed with OPBR.METHODS We analyzed 362 patients undergoing cholecystectomy(November 2020 to January 2022).Intraoperative bile samples were assayed for amylase(>110 U/L indicated OPBR).CT features,including stone density and visibility,were compared between 54 OPBR and 308 controls.Stone attenuation(HU)was measured under standardized conditions(uCT-780,120 kVp,160 mAs).Logistic regression and receiver operating characteristic curve analysis identified independent OPBR predictors,forming a validated nomogram.RESULTS OPBR patients exhibited significantly higher rates of CT-invisible stones(35.2%vs 12.3%)and uniform stones(87%vs 73.1%)along with lower overall stone density(P=0.01).Logistic regression identified stone visibility,uniformity,and density as independent predictors.A nomogram integrating these features with patient age achieved high diagnostic accuracy(area under the curve=0.71).CONCLUSION CT imaging distinctly identifies gallbladder stone density,indicating a heightened risk of OPBR in patients with uniform and CT-invisible stones.Such imaging is crucial for preoperative assessments to evaluate potential recurrent biliary pathologies post-cholecystectomy.展开更多
A series of heteronuclear yttrium-nickel monoxide carbonyl complexes YNiO(CO)_(n)^(-)(n=1-5)were generated in a pulsed-laser vaporization source and characterized by mass-selected photoelectron velocity-map spectrosco...A series of heteronuclear yttrium-nickel monoxide carbonyl complexes YNiO(CO)_(n)^(-)(n=1-5)were generated in a pulsed-laser vaporization source and characterized by mass-selected photoelectron velocity-map spectroscopy combined with theoretical calculations.CO ligand-mediated reactivity in CO oxidation of yttrium-nickel monoxide carbonyl complexes was experimentally and theoretically identified.During the consecutive CO adsorption,aμ^(2)-O linear structure was most favorable for YNiO(CO)_(n)^(-)(n=1,2),then a structure in which the terminal O was bonded to the Y atom became favored for YNiO(CO)_(3)^(-),and finally a structure bearing a CO_(2)moiety was most favorable for YNiO(CO)_(n)^(-)(n=4,5).Theoretical calculations indicated that the Ni atom acted as an electron acceptor and accumulated electron density at n≤3,and then served as an electron donor along with the Y atom to contribute electron density in the rearrangement that accompanied CO oxidation at n>3.展开更多
Ferroelectric materials find extensive applications in brake systems due to their capability to convert electrical energy into mechanical energy.Recent research has focused on lead-free materials for their environment...Ferroelectric materials find extensive applications in brake systems due to their capability to convert electrical energy into mechanical energy.Recent research has focused on lead-free materials for their environmentally friendly characteristics.However,they exhibit several challenges such as significant negative strain,limited strain values,and large driving field.In this work,novel preparation techniques(electrospinning)were utilized for BaTiO_(3)to introduce oxygen vacancies and barium defects,facilitating the creation of oriented defect dipoles coupled with an intrinsic electric field(Ei)after poling and aging.Due to the existence of Ei,two minimum points in the strain hysteresis loop were shifted to the same quadrant in the Strain-Electric field space.Thus,when applying an electric field along the Ei direction,negative strain is eliminated.Additionally,the actual electric field is the sum of the applied electric field and Ei,thereby reducing the required driving field of the piezoelectric.The stretching of defect dipoles under the electric field further amplified the total strain.Through the proposed mechanisms,this work achieved a substantial unipolar electrostrain of 1.04%under a relatively low electric field(30 kV/cm)in BaTiO_(3).This work successfully addressed the challenges of high-driving electric fields,limited strain values,and negative strain,providing a comprehensive approach for improving field-induced strain performance through point defect engineering in ferroelectric materials.展开更多
Although conventional object detection methods achieve high accuracy through extensively annotated datasets,acquiring such large-scale labeled data remains challenging and cost-prohibitive in numerous real-world appli...Although conventional object detection methods achieve high accuracy through extensively annotated datasets,acquiring such large-scale labeled data remains challenging and cost-prohibitive in numerous real-world applications.Few-shot object detection presents a new research idea that aims to localize and classify objects in images using only limited annotated examples.However,the inherent challenge in few-shot object detection lies in the insufficient sample diversity to fully characterize the sample feature distribution,which consequently impacts model performance.Inspired by contrastive learning principles,we propose an Implicit Feature Contrastive Learning(IFCL)module to address this limitation and augment feature diversity for more robust representational learning.This module generates augmented support sample features in a mixed feature space and implicitly contrasts them with query Region of Interest(RoI)features.This approach facilitates more comprehensive learning of both intra-class feature similarity and inter-class feature diversity,thereby enhancing the model’s object classification and localization capabilities.Extensive experiments on PASCAL VOC show that our method achieves a respective improvement of 3.2%,1.8%,and 2.3%on 10-shot of three Novel Sets compared to the baseline model FPD.展开更多
Against the backdrop of digital education,the campus network has become an indispensable infrastructure in universities,yet the limitations of traditional operation models have become increasingly prominent.This paper...Against the backdrop of digital education,the campus network has become an indispensable infrastructure in universities,yet the limitations of traditional operation models have become increasingly prominent.This paper systematically presents the entire process of the free campus network reform initiated by Dalian Jiaotong University,focusing on its background,implementation paths,existing challenges,and optimization strategies.It explores the construction of an on-demand service system for campus networks,and practical experience can provide some reference and guidance for sister universities.展开更多
文摘Secondary injury following spinal cord injury is primarily characterized by a complex inflammatory response,with resident microglia and infiltrating macrophages playing pivotal roles.While previous studies have grouped these two cell types together based on similarities in structure and function,an increasing number of studies have demonstrated that microglia and macrophages exhibit differences in structure and function and have different effects on disease processes.In this study,we used single-cell RNA sequencing and spatial transcriptomics to identify the distinct evolutionary paths of microglia and macrophages following spinal cord injury.Our results showed that microglia were activated to a pro-inflammatory phenotype immediately after spinal cord injury,gradually transforming to an anti-inflammatory steady state phenotype as the disease progressed.Regarding macrophages,our findings highlighted abundant communication with other cells,including fibroblasts and neurons.Both pro-inflammatory and neuroprotective effects of macrophages were also identified;the pro-inflammatory effect may be related to integrin β2(Itgb2) and the neuroprotective effect may be related to the oncostatin M pathway.These findings were validated by in vivo experiments.This research underscores differences in the cellular dynamics of microglia and macrophages following spinal cord injury,and may offer new perspectives on inflammatory mechanisms and potential therapeutic targets.
基金financial support by Sichuan Science and Technology,China(No.2023YFG0070).
文摘Fuel cell electric vehicles hold great promise for a diverse range of applications in reducing greenhouse gas emissions.In power fuel cell systems,hydrogen fuel serves as an energy vector.To ensure its suitability,it is necessary for the quality of hydrogen to adhere to the standards set by ISO 14687:2019,which sets maximum limits for 14 impurities in hydrogen,aiming to prevent any degradation of fuel cell performance.Ammonia(NH_(3))is a prominent pollutant in fuel cells,and accurate measurements of its concentration are crucial for hydrogen fuel cell quantity.In this study,a novel detection platform was developed for determining NH_(3)in real hydrogen samples.The online analysis platform integrates a self-developed online dilution module with a Fourier transform infrared spectrometer(ODM-FTIR).The ODM-FTIR can be operated fully automatically with remote operation.Under the optimum conditions,this method achieved a wide linear range between(50∼1000)nmol/mol.The limit of detection(LOD)was as low as 2 nmol/mol with a relative standard deviation(RSD,n=7)of 3.6%at a content of 50 nmol/mol.To ensure that the quality of the hydrogen products meets the requirement of proton exchange membrane fuel cell vehicles(PEMFCV),the developed ODM-FTIR system was applied to monitor the NH_(3)content in Chengdu Hydrogen Energy Co.,Ltd.for 21 days during Chengdu 2021 FISU World University Games.The proposed method retains several unique advantages,including a low detection limit,excellent repeatability,high accuracy,high speed,good stability,and calibration flexibility.It is an effective analytical method for accurately quantifying NH_(3)in hydrogen,especially suitable for online analysis.It also provides a new idea for the analysis of other impurity components in hydrogen.
基金the National Natural Science Foundation of China(No.82374295)the National Key R&D Program of China(No.2021YFE0111100)+1 种基金the Science and Technol-ogy Partnership Program by the Ministry of Science and Technol-ogy of China(No.KY202201002)the Jiangsu Provincial De-partment of Science and Technology(No.BZ2022017).
文摘Cardiovascular disease(CVD)is a major global health challenge,which causes significant illness and death worldwide.These include a range of conditions that affect the heart and blood vessels,including coro-nary artery disease,stroke,peripheral artery disease,and heart failure.Despite advances in medicine and healthcare delivery,CVD continues to have a serious impact on individuals,families,and the healthcare system.This review begins by delineating the merits and demerits of commonly employed synthetic and natural materials for artificial blood vessels.It delves into various techniques commonly employed in the fabrication of artificial blood vessels,encompassing advanced textile technologies,electrospinning,ther-mally induced phase separation,and 3D printing.The review critically analyzes the attributes of different preparation methodologies alongside the latest advancements in research.The review also outlines the requisite performance requirements for artificial blood vessels,which encompass robust mechanical prop-erties,appropriate porosity,exceptional compatibility,and antibacterial attributes.It provides a succinct overview of ongoing effort s in vascular functionalization,particularly emphasizing thrombus mitigation,promotion of endothelialization,and enhancement of nitric oxide production.The review finally encap-sulates the primary challenges confronting vascular grafts and prospective avenues for future research.
基金supported by the National Natural Science Foundation of China, Nos.81971151 (to YW), 82102528 (to XL), 82102583 (to LW)the Natural Science Foundation of Guangdong Province, China, Nos.2020A1515010265 (to YW), 2020A1515110679 (to XL), and 2021A1515010358 (to XL)
文摘Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction.However,the mechanisms involved remain unclear.In this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming phenotypes.The expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury.In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between them.We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway.This,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways.In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function recovery.Overall,Gas6 may play a role in the treatment of spinal cord injury.It can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.
基金supported by Chinese Association of Preventive Medicine-Vaccine and Immunization Youth Talent Support Project(CPMAQT-YM0314)Shandong medical and health science and technology development plan project(202012050267)Shandong Center for Disease Control and Prevention-Youth Innovation Fund Project(QC-202301).
文摘Background:This study investigated the relationship between meteorological factors and daily outpatient visits to rabies post-exposure prophylaxis clinics to inform animal injury prevention strategies.Methods:Daily outpatient visit data from rabies post-exposure prophylaxis clinics in Jinan and corresponding meteorological data were collected from January 1,2020,to December 31,2022.A generalized additive model was used to quantitatively assess the relationship between these factors.A total of 202,010 patients visited these clinics during this period.Results:Daily mean,maximum,and minimum temperatures,and relative humidity were positively associated with outpatient visits.A 1°C increase in mean,maximum,and minimum temperatures corresponded to increases in daily visits of 1.65%(95%Confidence Interval(CI):1.55–1.76),1.59%(95%CI:1.50–1.69),and 1.27%(95%CI:1.17–1.36)respectively.Each 1%increase in relative humidity was associated with a 0.18%(95%CI:0.15–0.20)increase in visits.Mean pressure was negatively associated with outpatient visits,the outpatient visits decreased by 0.91%(95%CI:−1.71 to−0.11)for every 1 kPa increased in mean pressure.Conclusion:The change of meteorological factors will lead to the increase of outpatient visits in rabies exposure treatment clinic.
基金supported by the Science Center of the National Science Foundation of China(Grant No.52088101)the National Key Research and Development Program of China(Grant Nos.2023YFA1406400,2021YFA1400300,and 2023YFA1607403)the National Natural Science Foundation of China(Grant Nos.T2394472 and T2394470).
文摘The two-dimensional electron gas(2DEG)formed at the interface between two oxide insulators provides new opportunities for electronics and spintronics.The broken inversion symmetry at the heterointerface results in a Rashba spin-orbit coupling(RSOC)effect that enables the conversion between spin and charge currents.However,conducting oxide interfaces that simultaneously exhibit strong RSOC and high carrier mobility-a combination query for achieving high spin-to-charge inter-conversion efficiencies-remain scarce.Herein,we report a correlated 2DEG with giant Rashba splitting and high electron mobility in(111)-oriented EuTiO_(3)/KTaO_(3)(ETO/KTO)heterostructures under light illumination.Upon light modulation,a unique carrier-dependent giant anomalous Hall effect,the signature of spin-polarized 2DEG,emerges with a sign crossover at a carrier density of approximately 5.0×10^(13)cm^(-2),highlighting dramatic changes in the band topology of KTO(111)interface.Furthermore,at 2 K,the carrier mobility is enhanced from 103 cm^(2)·V^(-1)·s^(-1)to 1800 cm^(2)·V^(-1)·s^(-1),a remarkable enhancement of approximately 20 times.Accompanying with a giant Rashba coefficient αR up to 360meV·˚A,this high mobility ferromagnetic 5d oxide 2DEG is predicted to achieve a giant spin-to-charge conversion efficiency ofλ~10 nm,showing great potential for designing low-power spin-orbitronic devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.12475081 and 12105153)the Natural Science Foundation of Shandong Province(Grant Nos.ZR2021MA082 and ZR2022ZD26)Taishan Scholar Project of Shandong Province(Grant No.tsqn202103062).
文摘The X(3872)is theoretically predicted to have a spin-0 partner state denoted as X_(0).Assuming the X_(0)as a molecular bound state,we calculate the decay widths of X_(0)→VV and X_(0)→PP(V and P stand for light vector and pseudoscalar mesons,respectively)via intermediate charmed meson loops.Three different configurations of the X_(0),i.e.,pure neutral components(θ=0),isospin singlet(θ=π/4),and pure charged components(θ=π/2),are investigated.Within a commonly accepted range of the model parameterα,the predicted decay widths of X_(0)→VV are on the order of a few hundred keV,while the decay widths of X_(0)→PP can reach several MeV.The X_(0)→ρρandππhave larger decay rates.The relative width ratios between the channels are nearly model-independent.Moreover,among those channels only with isovector or isoscalar mesons,the relevant ratios are also independent of the phase angle.The predicted ratios are helpful for searching the X_(0)in the future experiments at BESIII and Belle II.
基金supported by the National Natural Science Foundation of China(Grants Nos.42130511,42261134537 and 41602192)funded by the Russian Science Foundation(Grant No.23-44-00067)+2 种基金supported by the Swedish Research Council(Vetenskaps lijeradet,Grant No.2023-00605)the Marianne and Marcus Wallenberg Foundation(Grant No.MMW 2022-0114)the Centre for Advanced Study(CAS)at the Norwegian Academy of Science and Letters,which funded and hosted the research project“The Nordic Little Ice Age”during the 2024-2025 academic year。
文摘Radial growth of trees is highly sensitive to environmental changes,but the effect of climate on tree rings in Qinghai spruce(Picea crassifolia),a widely distributed endemic conifer in western China,is more complex than in many other conifers.A comprehensive understanding of the spatiotemporal climatic responses of its rings is needed to develop theoretical basis for designing strategies for its conservation and management.Here,our synthesis of the literature on responses of radial growth of Qinghai spruce to monthly climate variables in different environmental conditions by meta-analysis showed that precipitation and drought severity are the main limiting factors for Qinghai spruce radial growth in the semiarid region of northwestern China.In warmer and drier areas,radial growth of Qinghai spruce is mainly limited by drought.In the areas north of the 600-mm annual precipitation isoline,the tree-ring width(TRW)was significantly positively correlated with precipitation and significantly negatively correlated with temperature during the growing season(June-August).The limiting effect of drought on Qinghai spruce is also gradually increasing from southeast to northwest,to the west of 103°E and within 37°N-39°N.
文摘BACKGROUND Insomnia is a common sleep disorder that negatively impacts quality of life and is frequently comorbid with depression and anxiety.Chronic insomnia affects approximately 15%of the global population,with higher prevalence among females and the elderly.While existing research suggests a bidirectional relationship between insomnia and emotional disorders,the specific impact of insomnia severity on depression,anxiety,and quality of life remains unclear.This study investigates the correlation between insomnia severity and these factors in psychiatric outpatients,hypothesizing that greater insomnia severity is associated with higher levels of depression and anxiety,as well as poorer quality of life.AIM To explore the correlation between insomnia severity and depression,anxiety,and quality of life in primary chronic insomnia patients.METHODS From June to December 2023,345 patients with primary insomnia in Chifeng city were recruited and divided into three groups based on Pittsburgh sleep quality index(PSQI)scores:Mild(n=137),moderate(n=162),and severe(n=46).Demographic data were collected via questionnaires.Self-rating depression scale(SDS),self-rating anxiety scale(SAS),PSQI,and short form 36(SF-36)scores were compared,and Pearson and partial correlation analyses were performed.RESULTS The greater the degree of insomnia,the greater the symptoms of depression and anxiety(P<0.001).The more severe the insomnia,the lower the SF-36 score(excluding body pain),and the difference between the three groups was statist ically significant(P<0.001).Pearson correlation analysis and partial correlation analysis depicted the SDS score and SAS score were apparently positively correlated with the severity of insomnia(P<0.001).Pearson correlation analysis and partial correlation analysis depicted the SF-36 scores were apparently positively correlated with the severity of insomnia(P<0.05).CONCLUSION Depression and anxiety are independent factors influencing insomnia severity in primary chronic insomnia patients.Higher depression/anxiety levels correlate with worse insomnia,impacting quality of life.
基金financially supported by the National Natural Science Foundation of China(21905137)the Research Grants Council of Hong Kong(15307922,C5037-18G,C4005-22Y)+1 种基金RGC Senior Research Fellowship Scheme(SRFS2223-5S01)the Hong Kong Polytechnic University:Sir Sze-yuen Chung Endowed Professorship Fund(8-8480)。
文摘Semitransparent organic photovoltaics(ST-OPVs)for building integration represent a pivotal direction in the development of photovoltaic industry.Solution-processed silver nanowires(AgNWs)are considered promising candidates for transparent electrodes in semitransparent devices due to their high transparency-conductivity-efficiency merit,large-scale processability,and low cost.In this work,we develop two solution-processed organic–inorganic hybrid electrodes,named AgNWs-PD and AgNWsPC,utilizing AgNWs as the conductive framework and aliphatic amine-functionalized perylene-diimide(PDINN)as the sandwiched material,while AgNWs-PC exhibits significantly improved electrical conductivity and enhanced contact area with the underlying electron transport layer.The optimized device achieves a power conversion efficiency of 9.45%with an open circuit voltage of 0.846 V,a high filling factor of 75.4%,and an average visible transmittance(AVT)of 44.0%,delivering an outstanding light utilization efficiency(LUE)of 4.16%,which is the highest reported value for all solution-processed ST-OPVs.In addition,by coupling a 30-nm tellurium dioxide atop AgNWs-PC,the bifaciality factor of derivative devices improves from 73.7%to 99.4%,while maintaining a high bifacial LUE over 3.7%.Our results emphasize the superiority and effectiveness of PDINN-sandwiched AgNWs electrodes for highperformance and all solution-processed ST-OPVs.
基金supported by the National Natural Science Foundation of China(Nos.22125303,92361302,92061203,22103082,22273101,22288201,and 21327901)the National Key Research and Development Program of China(No.2021YFA1400501)+3 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0303304)Dalian Institute of Chemical Physics(No.DICPI202437)Chinese Academy of Sciences(No.GJJSTD20220001)the International Partnership Program of CAS(No.121421KYSB20170012)。
文摘It is highly challenging to precisely compare the impacts of anthropogenic pollutants on the photooxidation of isomeric volatile organic compounds with respect to molecular compositions and particle number/mass concentrations of secondary organic aerosols(SOAs).In this study,we conducted a series of well-defined indoor chamber experiments to compare the effects of NO_(x)(NO and NO_(2))on the photooxidation of isomeric monoterpenes ofβ-pinene and limonene.For the photooxidation ofβ-pinene with NO_(x),the increase of the initial concentrations of NO([NO]_(0))shows a monotonous suppression of the particle mass concentration,whereas the increase of[NO_(2)]_(0) shows a monotonous enhancement of the particle mass concentration.For the photooxidation of limonene with NO_(x),the increase of[NO]_(0) exhibits a monotonous suppression of the particle mass concentration,whereas the increase of[NO_(2)]_(0) shows a parabolic trend of the particle mass concentration.Utilizing a newly developed vacuum ultraviolet free electron laser(VUV-FEL),the online threshold photoionization mass spectrometry reveals a series of novel compounds at molecular weight(MW)=232 and 306 for theβ-pinene+NO_(x) system and MW=187,261,280,and 306 for the limonene+NO_(x) system.The molecular structures and formation pathways of these species were inferred,which led to the prediction of the diversity and difference of SOA products(i.e.,ester and peroxide accretion products)formed from different monoterpene precursors.To improve the predictions of future air quality,it is recommended that climate models should incorporate the NO_(x)-driven diurnal photooxidation of monoterpenes for SOA formation mechanisms.
基金supported by the Science and Technology Bureau of Xi’an project(24KGDW0049)the Key Research and Development Programof Shaanxi(2023-YBGY-264)the Key Research and Development Program of Guangxi(GK-AB20159032).
文摘In recent years,the country has spent significant workforce and material resources to prevent traffic accidents,particularly those caused by fatigued driving.The current studies mainly concentrate on driver physiological signals,driving behavior,and vehicle information.However,most of the approaches are computationally intensive and inconvenient for real-time detection.Therefore,this paper designs a network that combines precision,speed and lightweight and proposes an algorithm for facial fatigue detection based on multi-feature fusion.Specifically,the face detection model takes YOLOv8(You Only Look Once version 8)as the basic framework,and replaces its backbone network with MobileNetv3.To focus on the significant regions in the image,CPCA(Channel Prior Convolution Attention)is adopted to enhance the network’s capacity for feature extraction.Meanwhile,the network training phase employs the Focal-EIOU(Focal and Efficient Intersection Over Union)loss function,which makes the network lightweight and increases the accuracy of target detection.Ultimately,the Dlib toolkit was employed to annotate 68 facial feature points.This study established an evaluation metric for facial fatigue and developed a novel fatigue detection algorithm to assess the driver’s condition.A series of comparative experiments were carried out on the self-built dataset.The suggested method’s mAP(mean Average Precision)values for object detection and fatigue detection are 96.71%and 95.75%,respectively,as well as the detection speed is 47 FPS(Frames Per Second).This method can balance the contradiction between computational complexity and model accuracy.Furthermore,it can be transplanted to NVIDIA Jetson Orin NX and quickly detect the driver’s state while maintaining a high degree of accuracy.It contributes to the development of automobile safety systems and reduces the occurrence of traffic accidents.
文摘Intelligent Automation&Soft Computing has retracted the article titled“Line Trace Effective Comparison AlgorithmBased onWavelet Domain DTW”[1],Intell Automat Soft Comput.2019;25(2):359–366 at the request of the authors.DOI:10.31209/2019.100000097 URL:https://www.techscience.com/iasc/v25n2/39663 The article duplicates significant parts of a paper published in Journal of Intelligent&Fuzzy Systems[2].
基金the support from National Natural Science Foundation of China (No.52004179)the Fundamental Research Program of Shanxi Province,China (Nos.202403021211028,202303021211036)+1 种基金Shanxi Water and Wood New Carbon Materials Technology Co.,Ltd.,ChinaGuangdong One Nano Technology Co.,Ltd.,China。
文摘In order to restrain the huge volume expansion of bismuth(Bi)anodes in sodium ion batteries(SIBs),the core-shell structure Bi@mesoporous carbon nanospheres(Bi@mC)composite was designed and prepared by sol-gel method coupled heat treatment.Structural characterization displays that the average diameter of the as-prepared Bi@mC composites is about 200 nm and thickness of the N-doped mesoporous carbon shells is 20-30 nm.Electrochemical test and kinetic analysis results show that the mesoporous carbon shell can not only effectively relieve the stress caused by volume expansion of Bi and protect active material from pulverization caused by the stress during charging/discharging process,but also facilitate quick diffusion of sodium ions,thus improving rate and cycling performance.Bi@mC delivers a high specific capacity of 279 mA·h/g and a capacity retention of 97.6%after 3500 cycles at a current density of 5 A/g.Even at a high current density of 20 A/g,Bi@mC can still maintain a high specific capacity of 266 mA·h/g.Additionally,the Bi@mC//NVP full button sodium-ion batteries(SIBs)assembled using Bi@mC anode and Na_(3)V_(2)(PO_(4))_(3)(NVP)cathode deliver an energy density of 182 W·h/kg.
基金Supported by Key Specialty Construction Project of Shanghai Pudong New Area Health Commission,No.PWZzk2022-17Shanghai East Hospital Clinical Research Project,No.DFLC2022019the Featured Clinical Discipline Project of Shanghai Pudong District,No.PWYts2021-06.
文摘BACKGROUND Occult pancreaticobiliary reflux(OPBR)is characterized by the absence of congenital anomalies at the pancreaticobiliary junction yet leads to altered bile composition and an increased incidence of gallbladder stones.AIM To explore the computed tomography(CT)imaging characteristics of gallbladder stones in patients diagnosed with OPBR.METHODS We analyzed 362 patients undergoing cholecystectomy(November 2020 to January 2022).Intraoperative bile samples were assayed for amylase(>110 U/L indicated OPBR).CT features,including stone density and visibility,were compared between 54 OPBR and 308 controls.Stone attenuation(HU)was measured under standardized conditions(uCT-780,120 kVp,160 mAs).Logistic regression and receiver operating characteristic curve analysis identified independent OPBR predictors,forming a validated nomogram.RESULTS OPBR patients exhibited significantly higher rates of CT-invisible stones(35.2%vs 12.3%)and uniform stones(87%vs 73.1%)along with lower overall stone density(P=0.01).Logistic regression identified stone visibility,uniformity,and density as independent predictors.A nomogram integrating these features with patient age achieved high diagnostic accuracy(area under the curve=0.71).CONCLUSION CT imaging distinctly identifies gallbladder stone density,indicating a heightened risk of OPBR in patients with uniform and CT-invisible stones.Such imaging is crucial for preoperative assessments to evaluate potential recurrent biliary pathologies post-cholecystectomy.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2021QB215)the National Natural Science Foundation of China(Nos.22273101,22125303,92061203,21327901,and 22288201)+2 种基金Dalian Institute of Chemical Physics(No.DICP I202437)the Talent Induction Program for Youth Innovation Teams in Colleges and Universities of Shandong Province(No.2022-2024)the Talent Introduction Research Start-up Funds of Ludong University(No.20212026)。
文摘A series of heteronuclear yttrium-nickel monoxide carbonyl complexes YNiO(CO)_(n)^(-)(n=1-5)were generated in a pulsed-laser vaporization source and characterized by mass-selected photoelectron velocity-map spectroscopy combined with theoretical calculations.CO ligand-mediated reactivity in CO oxidation of yttrium-nickel monoxide carbonyl complexes was experimentally and theoretically identified.During the consecutive CO adsorption,aμ^(2)-O linear structure was most favorable for YNiO(CO)_(n)^(-)(n=1,2),then a structure in which the terminal O was bonded to the Y atom became favored for YNiO(CO)_(3)^(-),and finally a structure bearing a CO_(2)moiety was most favorable for YNiO(CO)_(n)^(-)(n=4,5).Theoretical calculations indicated that the Ni atom acted as an electron acceptor and accumulated electron density at n≤3,and then served as an electron donor along with the Y atom to contribute electron density in the rearrangement that accompanied CO oxidation at n>3.
基金supported by the National Nature Science Foundation(Nos.52372125 and 52333009)the National Key Research and Development Project(Nos.2020YFC1521900 and 2020YFC1521904)+4 种基金the Shaanxi Provincial Science Foundation(No.2021GXLH-01-11)the Yulin Project(No.2022-19-11)the Fundamental Research Funds for the Central Universities(No.D5000230071)the 111 Program(No.B08040)of MOE of Chinasponsored by Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(No.CX2024063).
文摘Ferroelectric materials find extensive applications in brake systems due to their capability to convert electrical energy into mechanical energy.Recent research has focused on lead-free materials for their environmentally friendly characteristics.However,they exhibit several challenges such as significant negative strain,limited strain values,and large driving field.In this work,novel preparation techniques(electrospinning)were utilized for BaTiO_(3)to introduce oxygen vacancies and barium defects,facilitating the creation of oriented defect dipoles coupled with an intrinsic electric field(Ei)after poling and aging.Due to the existence of Ei,two minimum points in the strain hysteresis loop were shifted to the same quadrant in the Strain-Electric field space.Thus,when applying an electric field along the Ei direction,negative strain is eliminated.Additionally,the actual electric field is the sum of the applied electric field and Ei,thereby reducing the required driving field of the piezoelectric.The stretching of defect dipoles under the electric field further amplified the total strain.Through the proposed mechanisms,this work achieved a substantial unipolar electrostrain of 1.04%under a relatively low electric field(30 kV/cm)in BaTiO_(3).This work successfully addressed the challenges of high-driving electric fields,limited strain values,and negative strain,providing a comprehensive approach for improving field-induced strain performance through point defect engineering in ferroelectric materials.
基金funded by the China Chongqing Municipal Science and Technology Bureau,grant numbers CSTB2024TIAD-CYKJCXX0009,CSTB2024NSCQ-LZX0043,CSTB2022NSCQ-MSX0288Chongqing Municipal Commission of Housing and Urban-Rural Development,grant number CKZ2024-87+3 种基金the Chongqing University of Technology Graduate Education High-Quality Development Project,grant number gzlsz202401the Chongqing University of Technology—Chongqing LINGLUE Technology Co.,Ltd.Electronic Information(Artificial Intelligence)Graduate Joint Training Basethe Postgraduate Education and Teaching Reform Research Project in Chongqing,grant number yjg213116the Chongqing University of Technology-CISDI Chongqing Information Technology Co.,Ltd.Computer Technology Graduate Joint Training Base.
文摘Although conventional object detection methods achieve high accuracy through extensively annotated datasets,acquiring such large-scale labeled data remains challenging and cost-prohibitive in numerous real-world applications.Few-shot object detection presents a new research idea that aims to localize and classify objects in images using only limited annotated examples.However,the inherent challenge in few-shot object detection lies in the insufficient sample diversity to fully characterize the sample feature distribution,which consequently impacts model performance.Inspired by contrastive learning principles,we propose an Implicit Feature Contrastive Learning(IFCL)module to address this limitation and augment feature diversity for more robust representational learning.This module generates augmented support sample features in a mixed feature space and implicitly contrasts them with query Region of Interest(RoI)features.This approach facilitates more comprehensive learning of both intra-class feature similarity and inter-class feature diversity,thereby enhancing the model’s object classification and localization capabilities.Extensive experiments on PASCAL VOC show that our method achieves a respective improvement of 3.2%,1.8%,and 2.3%on 10-shot of three Novel Sets compared to the baseline model FPD.
文摘Against the backdrop of digital education,the campus network has become an indispensable infrastructure in universities,yet the limitations of traditional operation models have become increasingly prominent.This paper systematically presents the entire process of the free campus network reform initiated by Dalian Jiaotong University,focusing on its background,implementation paths,existing challenges,and optimization strategies.It explores the construction of an on-demand service system for campus networks,and practical experience can provide some reference and guidance for sister universities.
