In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strat...In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road cracks.This methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of images.The study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence image.The extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic image.Additionally,a threshold value is set based on the crack elevation change to extract the aligned roadway point cloud.The three-dimensional data pertaining to the cracks can be acquired.The experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road cracks.The utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road cracks.This approach exhibits superior accuracy when compared to conventional methods.Moreover,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic safety.Consequently,this technique finds extensive application in the domains of intelligent transportation and urbanization development.The technology exhibits significant promise for use in the domains of intelligent transportation and city development.展开更多
The energy storage behaviors of MnO_(2) for aqueous Zn-MnO_(2) batteries mainly depend on the Zn^(2+)/H^(+)intercalation but are limited by poor ion/electron migration dynamics and stability.Herein,a strategy is propo...The energy storage behaviors of MnO_(2) for aqueous Zn-MnO_(2) batteries mainly depend on the Zn^(2+)/H^(+)intercalation but are limited by poor ion/electron migration dynamics and stability.Herein,a strategy is proposed that promoting proton migration kinetics ameliorates H^(+)storage activity by introducing Ni^(2+)intoγ-MnO_(2)(Ni-MnO_(2)).Ni^(2+)can lower the diffusion barrier of H^(+)and selectively induce the ion intercalation,thereby alleviating the electrostatic interaction with the lattice.Moreover,Ni^(2+)enables the adjacent[MnO6]octahedrons to have better electron conductivity.The Ni-MnO_(2) exhibits superior rate performance(nearly four times specific capacity compared with MnO_(2))and ultra-long-cycle stability(100%of capacity retention after 11000 cycles at 3.0 A g^(-1)).The calculation indicates that the Ni-MnO_(2) allows H^(+)migrate rapidly along the one-dimensional tunnel due to reduction of the activation energy caused by Ni^(2+)regulating,thus achieving excellent reaction kinetics.This work brings great potential for the development of high-performance aqueous Zn-MnO_(2) batteries.展开更多
Lithium(Li)metal electrodes show significantly different reversibility in the electrolytes with different salts.However,the understanding on how the salts impact on the Li loss remains unclear.Herein,using the electro...Lithium(Li)metal electrodes show significantly different reversibility in the electrolytes with different salts.However,the understanding on how the salts impact on the Li loss remains unclear.Herein,using the electrolytes with different salts(e.g.,lithium hexafluorophosphate(LiPF_(6)),lithium difluoro(oxalato)borate(LiDFOB),and lithium bis(fluorosulfonyl)amide(LiFSI))as examples,we decouple the irreversible Li loss(SEI Li^(+)and“dead”Li)during cycling.It is found that the accumulation of both SEI Li^(+)and“dead”Li may be responsible to the irreversible Li loss for the Li metal in the electrolyte with LiPF_(6)salt.While for the electrolytes with LiDFOB and LiFSI salts,the accumulation of“dead”Li predominates the Li loss.We also demonstrate that lithium nitrate and fluoroethylene carbonate additives could,respectively,function as the“dead”Li and SEI Li^(+)inhibitors.Inspired by the above understandings,we propose a universal procedure for the electrolyte design of Li metal batteries(LMBs):(i)decouple and find the main reason for the irreversible Li loss;(ii)add the corresponding electrolyte additive.With such a Li-loss-targeted strategy,the Li reversibility was significantly enhanced in the electrolytes with 1,2-dimethoxyethane,triethyl phosphate,and tetrahydrofuran solvents.Our strategy may broaden the scope of electrolyte design toward practical LMBs.展开更多
The alkaline zinc-based batteries with high energy density are becoming a research hotspot.However,the poor cycle stability and low-rate performance limit their wide application.Herein,ultra-thin CoNiO2 nanosheet with...The alkaline zinc-based batteries with high energy density are becoming a research hotspot.However,the poor cycle stability and low-rate performance limit their wide application.Herein,ultra-thin CoNiO2 nanosheet with rich oxygen defects anchored on the vertically arranged Ni nanotube arrays(Od-CNO@Ni NTs)is used as a positive material for rechargeable alkaline Ni–Zn batteries.As the highly uniform Ni nanotube arrays provide a fast electron/ion transport path and abundant active sites,the Od-CNO@Ni NTs electrode delivers excellent capacity(432.7 mAh g^(−1))and rate capability(218.3 mAh g^(−1) at 60 A g^(−1)).Moreover,our Od-CNO@Ni NTs//Zn battery is capable of an ultra-long lifespan(93.0%of initial capacity after 5000 cycles),extremely high energy density of 547.5 Wh kg^(−1) and power density of 92.9 kW kg^(−1)(based on the mass of cathode active substance).Meanwhile,the theoretical calculations reveal that the oxygen defects can enhance the interaction between electrode surface and electrolyte ions,contributing to higher capacity.This work opens a reasonable idea for the development of ultra-durable,ultra-fast,and high-energy Ni–Zn battery.展开更多
It is generally believed that,in ghost imaging,there has to be a compromise between resolution and visibility.Here we propose and demonstrate an iterative filtered ghost imaging scheme whereby a super-resolution image...It is generally believed that,in ghost imaging,there has to be a compromise between resolution and visibility.Here we propose and demonstrate an iterative filtered ghost imaging scheme whereby a super-resolution image of a grayscale object is achieved,while at the same time the signal-to-noise ratio(SNR)and visibility are greatly improved,without adding complexity.The dependence of the SNR,visibility,and resolution on the number of iterations is also investigated and discussed.Moreover,with the use of compressed sensing the sampling number can be reduced to less than 1%of the Nyquist limit,while maintaining image quality with a resolution that can exceed the Rayleigh diffraction bound by more than a factor of 10.展开更多
A filtered ghost imaging(GI)protocol is proposed that enables the Rayleigh diffraction limit to be exceeded in an intensity correlation system;a super-resolution reconstructed image is achieved by low-pass filtering o...A filtered ghost imaging(GI)protocol is proposed that enables the Rayleigh diffraction limit to be exceeded in an intensity correlation system;a super-resolution reconstructed image is achieved by low-pass filtering of the measured intensities.In a lensless GI experiment performed with spatial bandpass filtering,the spatial resolution can exceed the Rayleigh diffraction bound by more than a factor of 10.The resolution depends on the bandwidth of the filter,and the relationship between the two is investigated and discussed.In combination with compressed sensing programming,not only high resolution can be maintained but also image quality can be improved,while a much lower sampling number is sufficient.展开更多
Microplastics have a constant effect on aquatic life and are constantly being researched, they have been gradually observed and analysed in marine and freshwater ecosystems, and possible effects in freshwater ecosyste...Microplastics have a constant effect on aquatic life and are constantly being researched, they have been gradually observed and analysed in marine and freshwater ecosystems, and possible effects in freshwater ecosystems are rising in importance. A literature review has been completed to outline the present state of awareness of microplastics in freshwater ecosystems in Ghana;in particular, the environmental fate, sources, effects in aquatic life and implications on their environments. Although we found that there was a dramatic increase in research and publications on these subjects, relatively few studies had examined the sources, fate and impacts of microplastics in the water bodies of Ghana and there was insufficient data on the extent of microplastics in freshwaters in Ghana. Studies in which Ghanaian waterbodies had quantified microplastics were considered of the greatest importance. We further assess current depth of knowledge of microplastics in aquatic ecosystems in which Ghanaian ecosystem-specific information was not readily available. Although this study may not be a comprehensive overview of the findings, it is assumed that this is an objective representation of the existing state of awareness about microplastics in the aquatic environment in Ghana.展开更多
To advance the field of science and technology,we need to revitalize the development of science and technology through innovation.The development of science and technology has many beneficial implications on the revit...To advance the field of science and technology,we need to revitalize the development of science and technology through innovation.The development of science and technology has many beneficial implications on the revitalization of the country.For this reason,universities in China should give full attention to their role as the main propeller of science and technology.“Streamlining administration,delegating powers,improving regulation,and strengthening services”is a policy issued by the Chinese government for the management of science and technology funds in colleges and universities.Based on the policy of“streamlining administration,delegating powers,improving regulation,and strengthening services,”colleges and universities must optimize the management of science and technology funds for their efficient use.In this paper,we analyzed the importance of the policy and put forward an effective management strategy,aiming to improve the management of science and technology funds in colleges and universities.展开更多
Metabolic-associated fatty liver disease(MAFLD)is a new disease definition,and is proposed to replace the previous name,nonalcoholic fatty liver disease(NAFLD).Globally,MAFLD/NAFLD is the most common liver disease,wit...Metabolic-associated fatty liver disease(MAFLD)is a new disease definition,and is proposed to replace the previous name,nonalcoholic fatty liver disease(NAFLD).Globally,MAFLD/NAFLD is the most common liver disease,with an incidence rate ranging from 6%to 35%in adult populations.The pathogenesis of MAFLD/NAFLD is closely related to insulin resistance(IR),and the genetic susceptibility to acquired metabolic stress-associated liver injury.Similarly,the gut microbiota in MAFLD/NAFLD is being revaluated by scientists,as the gut and liver influence each other via the gut-liver axis.Ferroptosis is a novel form of programmed cell death caused by iron-dependent lipid peroxidation.Emerging evidence suggests that ferroptosis has a key role in the pathological progression of MAFLD/NAFLD,and inhibition of ferroptosis may become a novel therapeutic strategy for the treatment of NAFLD.This review focuses on the main mechanisms behind the promotion of MAFLD/NAFLD occurrence and development by the intestinal microbiota and ferroptosis.It outlines new strategies to target the intestinal microbiota and ferroptosis to facilitate future MAFLD/NAFLD therapies.展开更多
Exosomes carry and transmit signaling molecules used for intercellular communication.The generation and secretion of exosomes is a multistep interlocking process that allows simultaneous control of multiple regulatory...Exosomes carry and transmit signaling molecules used for intercellular communication.The generation and secretion of exosomes is a multistep interlocking process that allows simultaneous control of multiple regulatory sites.Protein molecules,mainly RAB GTPases,cytoskeletal proteins and soluble N-ethylmaleimide-sensitive fusion attachment protein receptor(SNARE),are specifically regulated in response to pathological conditions such as altered cellular microenvironment,stimulation by pathogenic factors,or gene mutation.This interferes with the smooth functioning of endocytosis,translocation,degradation,docking and fusion processes,leading to changes in the secretion of exosomes.Large numbers of secreted exosomes are disseminated by the flow of body fluids and absorbed by the recipient cells.By transmitting characteristic functional proteins and genetic information produced under disease conditions,exosomes can change the physiological state of the recipient cells and their microenvironment.The microenvironment,in turn,affects the occurrence and development of disease.Therefore,this review will discuss the mechanism by which exosome secretion is regulated in cells following the formation of mature secretory multivesicular bodies(MVBs).The overall aim is to find ways to eliminate disease-derived exosomes at their source,thereby providing an important new basis for the clinical treatment of disease.展开更多
Surface-enhanced Raman scattering(SERS)has been used in atmospheric aerosol detection as it enables the high-resolution analysis of particulate matter.However,its use in the detection of historical samples without dam...Surface-enhanced Raman scattering(SERS)has been used in atmospheric aerosol detection as it enables the high-resolution analysis of particulate matter.However,its use in the detection of historical samples without damaging the sampling membrane while achieving effective transfer and the high-sensitivity analysis of particulate matter from sample films remains challenging.In this study,a new type of SERS tape was developed,consisting of Au nanoparticles(NPs)on an adhesive double-sided Cu film(DCu).The enhanced electromagnetic field generated by the coupled resonance of the local surface plasmon resonances of AuNPs and DCu led to an enhanced SERS signal with an experimental enhancement factor of 10^(7).The AuNPs were semi-embedded and distributed on the substrate,and the viscous DCu layer was exposed,enabling particle transfer.The substrates exhibited good uniformity and favorable reproducibility with relative standard deviations of 13.53%and 9.74%respectively,and the substrates could be stored for 180 days with no signs of signal weakening.The application of the substrates was demonstrated by the extraction and detection of malachite green and ammonium salt particulate matter.The results demonstrated that SERS substrates based on AuNPs and DCu are highly promising in real–world environmental particle monitoring and detection.展开更多
Due to the rapid advancement of the transportation industry and the continual increase in pavement infrastructure,it is difficult to keep up with the huge road maintenance task by relying only on the traditional manua...Due to the rapid advancement of the transportation industry and the continual increase in pavement infrastructure,it is difficult to keep up with the huge road maintenance task by relying only on the traditional manual detection method.Intelligent pavement detection technology with deep learning techniques is available for the research and industry areas by the gradual development of computer vision technology.Due to the different characteristics of pavement distress and the uncertainty of the external environment,this kind of object detection technology for distress classification and location still faces great challenges.This paper discusses the development of object detection technology and analyzes classical convolutional neural network(CNN)architecture.In addition to the one-stage and two-stage object detection frameworks,object detection without anchor frames is introduced,which is divided according to whether the anchor box is used or not.This paper also introduces attention mechanisms based on convolutional neural networks and emphasizes the performance of these mechanisms to further enhance the accuracy of object recognition.Lightweight network architecture is introduced for mobile and industrial deployment.Since stereo cameras and sensors are rapidly developed,a detailed summary of three-dimensional object detection algorithms is also provided.While reviewing the history of the development of object detection,the scope of this review is not only limited to the area of pavement crack detection but also guidance for researchers in related fields is shared.展开更多
In recent years,the concept"northern ethnic dynasties"has been widely used when referring to dynasties established by ethnic groups from northern China,including Liao,Jin,Yuan,and Qing dynasty.When it comes ...In recent years,the concept"northern ethnic dynasties"has been widely used when referring to dynasties established by ethnic groups from northern China,including Liao,Jin,Yuan,and Qing dynasty.When it comes to the prolonged debates on the relation between ethnic groups and state,the traditional narrative of the dynastic history of Central Plains,which holds"sinicization"as its principal line,has been challenged;and the academia has been focusing on how to elaborate features and state forms of these northern ethnic dynasties.This article argues that,only by returning to the dynasty-based narrative of the evolvement of northern ethnic regimes,can we break the shackle of western-style"nation state"narrative;can we understand the fact that dynasticity transcends ethnicity in Chinese history;and can we thereby establish the correct view of history on the Chinese nation.展开更多
This paper has analyzed the asymmetric flow effect of fire-induced thermal flow in a horizontal tunnel under the natural ventilation condition by conducting large eddy simulations (LES). The key objective is to reveal...This paper has analyzed the asymmetric flow effect of fire-induced thermal flow in a horizontal tunnel under the natural ventilation condition by conducting large eddy simulations (LES). The key objective is to reveal and to have a better understanding of the asymmetric flow effect caused by the upstream and downstream tunnel length difference. The mechanism behind it can be explained based on the conservation of mass and dynamic force analysis on the smoke and fresh air. The strength of the asymmetric flow effect is characterized by the mass flow rate of the induced longitudinal flow (net mass flow rate of a cross-section). An empirical correlation to predict the induced longitudinal mass flow rate is proposed. Furthermore, the law of smoke and air flow distribution within a horizontal tunnel is established. The proportion of smoke (or air) flowing out (or coming in) through the opening increase (or decrease) linearly with the increasing distance between that opening to the fire location. The variation of the air flow with the longitudinal fire location in a tunnel is more sensitive than the smoke flow. Results have shown that as the fire approaches the tunnel exit from the middle of the tunnel, the smoke spilling out through this opening is reduced from 50% to 40%, while the fresh air incoming from this opening is increased from 50% to 100% and vice versa.展开更多
基金founded by National Key R&D Program of China (No.2021YFB2601200)National Natural Science Foundation of China (No.42171416)Teacher Support Program for Pyramid Talent Training Project of Beijing University of Civil Engineering and Architecture (No.JDJQ20200307).
文摘In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road cracks.This methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of images.The study employs a vehicle-mounted LiDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence image.The extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic image.Additionally,a threshold value is set based on the crack elevation change to extract the aligned roadway point cloud.The three-dimensional data pertaining to the cracks can be acquired.The experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road cracks.The utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road cracks.This approach exhibits superior accuracy when compared to conventional methods.Moreover,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic safety.Consequently,this technique finds extensive application in the domains of intelligent transportation and urbanization development.The technology exhibits significant promise for use in the domains of intelligent transportation and city development.
基金supported by the National Natural Science Foundation of China(No.52002122)the Science and Technology Department of Hubei Province(No.2019AAA038)+1 种基金the Project funded by China Postdoctoral Science Foundation(No.2021M690947)the Wuhan Yellow Crane Talent Program(No.2017-02).
文摘The energy storage behaviors of MnO_(2) for aqueous Zn-MnO_(2) batteries mainly depend on the Zn^(2+)/H^(+)intercalation but are limited by poor ion/electron migration dynamics and stability.Herein,a strategy is proposed that promoting proton migration kinetics ameliorates H^(+)storage activity by introducing Ni^(2+)intoγ-MnO_(2)(Ni-MnO_(2)).Ni^(2+)can lower the diffusion barrier of H^(+)and selectively induce the ion intercalation,thereby alleviating the electrostatic interaction with the lattice.Moreover,Ni^(2+)enables the adjacent[MnO6]octahedrons to have better electron conductivity.The Ni-MnO_(2) exhibits superior rate performance(nearly four times specific capacity compared with MnO_(2))and ultra-long-cycle stability(100%of capacity retention after 11000 cycles at 3.0 A g^(-1)).The calculation indicates that the Ni-MnO_(2) allows H^(+)migrate rapidly along the one-dimensional tunnel due to reduction of the activation energy caused by Ni^(2+)regulating,thus achieving excellent reaction kinetics.This work brings great potential for the development of high-performance aqueous Zn-MnO_(2) batteries.
基金This work was supported by the National Key Research and Development Program(2021YFB2400300)the National Natural Science Foundation of China(52272203)the Fundamental Research Funds for the Central Universities(2021GCRC001).
文摘Lithium(Li)metal electrodes show significantly different reversibility in the electrolytes with different salts.However,the understanding on how the salts impact on the Li loss remains unclear.Herein,using the electrolytes with different salts(e.g.,lithium hexafluorophosphate(LiPF_(6)),lithium difluoro(oxalato)borate(LiDFOB),and lithium bis(fluorosulfonyl)amide(LiFSI))as examples,we decouple the irreversible Li loss(SEI Li^(+)and“dead”Li)during cycling.It is found that the accumulation of both SEI Li^(+)and“dead”Li may be responsible to the irreversible Li loss for the Li metal in the electrolyte with LiPF_(6)salt.While for the electrolytes with LiDFOB and LiFSI salts,the accumulation of“dead”Li predominates the Li loss.We also demonstrate that lithium nitrate and fluoroethylene carbonate additives could,respectively,function as the“dead”Li and SEI Li^(+)inhibitors.Inspired by the above understandings,we propose a universal procedure for the electrolyte design of Li metal batteries(LMBs):(i)decouple and find the main reason for the irreversible Li loss;(ii)add the corresponding electrolyte additive.With such a Li-loss-targeted strategy,the Li reversibility was significantly enhanced in the electrolytes with 1,2-dimethoxyethane,triethyl phosphate,and tetrahydrofuran solvents.Our strategy may broaden the scope of electrolyte design toward practical LMBs.
基金This work was supported by the National Natural Science Foundation of China(No.52002122)the Science and Technology Department of Hubei Province(No.2019AAA038)+1 种基金the Project funded by China Postdoctoral Science Foundation(No.2021M690947)the Wuhan Yellow Crane Talent Program(No.2017-02).
文摘The alkaline zinc-based batteries with high energy density are becoming a research hotspot.However,the poor cycle stability and low-rate performance limit their wide application.Herein,ultra-thin CoNiO2 nanosheet with rich oxygen defects anchored on the vertically arranged Ni nanotube arrays(Od-CNO@Ni NTs)is used as a positive material for rechargeable alkaline Ni–Zn batteries.As the highly uniform Ni nanotube arrays provide a fast electron/ion transport path and abundant active sites,the Od-CNO@Ni NTs electrode delivers excellent capacity(432.7 mAh g^(−1))and rate capability(218.3 mAh g^(−1) at 60 A g^(−1)).Moreover,our Od-CNO@Ni NTs//Zn battery is capable of an ultra-long lifespan(93.0%of initial capacity after 5000 cycles),extremely high energy density of 547.5 Wh kg^(−1) and power density of 92.9 kW kg^(−1)(based on the mass of cathode active substance).Meanwhile,the theoretical calculations reveal that the oxygen defects can enhance the interaction between electrode surface and electrolyte ions,contributing to higher capacity.This work opens a reasonable idea for the development of ultra-durable,ultra-fast,and high-energy Ni–Zn battery.
基金supported by the National Key Research and Development Program of China(Grant No.2018YFB0504302)the National Natural Science Foundation of China(Grant No.61975229)Civil Space Project(Grant No.D040301)。
文摘It is generally believed that,in ghost imaging,there has to be a compromise between resolution and visibility.Here we propose and demonstrate an iterative filtered ghost imaging scheme whereby a super-resolution image of a grayscale object is achieved,while at the same time the signal-to-noise ratio(SNR)and visibility are greatly improved,without adding complexity.The dependence of the SNR,visibility,and resolution on the number of iterations is also investigated and discussed.Moreover,with the use of compressed sensing the sampling number can be reduced to less than 1%of the Nyquist limit,while maintaining image quality with a resolution that can exceed the Rayleigh diffraction bound by more than a factor of 10.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2018YFB0504302 and 2017YFB0503301)Defense Industrial Technology Development Program(Grant No.D040301-1)。
文摘A filtered ghost imaging(GI)protocol is proposed that enables the Rayleigh diffraction limit to be exceeded in an intensity correlation system;a super-resolution reconstructed image is achieved by low-pass filtering of the measured intensities.In a lensless GI experiment performed with spatial bandpass filtering,the spatial resolution can exceed the Rayleigh diffraction bound by more than a factor of 10.The resolution depends on the bandwidth of the filter,and the relationship between the two is investigated and discussed.In combination with compressed sensing programming,not only high resolution can be maintained but also image quality can be improved,while a much lower sampling number is sufficient.
文摘Microplastics have a constant effect on aquatic life and are constantly being researched, they have been gradually observed and analysed in marine and freshwater ecosystems, and possible effects in freshwater ecosystems are rising in importance. A literature review has been completed to outline the present state of awareness of microplastics in freshwater ecosystems in Ghana;in particular, the environmental fate, sources, effects in aquatic life and implications on their environments. Although we found that there was a dramatic increase in research and publications on these subjects, relatively few studies had examined the sources, fate and impacts of microplastics in the water bodies of Ghana and there was insufficient data on the extent of microplastics in freshwaters in Ghana. Studies in which Ghanaian waterbodies had quantified microplastics were considered of the greatest importance. We further assess current depth of knowledge of microplastics in aquatic ecosystems in which Ghanaian ecosystem-specific information was not readily available. Although this study may not be a comprehensive overview of the findings, it is assumed that this is an objective representation of the existing state of awareness about microplastics in the aquatic environment in Ghana.
文摘To advance the field of science and technology,we need to revitalize the development of science and technology through innovation.The development of science and technology has many beneficial implications on the revitalization of the country.For this reason,universities in China should give full attention to their role as the main propeller of science and technology.“Streamlining administration,delegating powers,improving regulation,and strengthening services”is a policy issued by the Chinese government for the management of science and technology funds in colleges and universities.Based on the policy of“streamlining administration,delegating powers,improving regulation,and strengthening services,”colleges and universities must optimize the management of science and technology funds for their efficient use.In this paper,we analyzed the importance of the policy and put forward an effective management strategy,aiming to improve the management of science and technology funds in colleges and universities.
基金the National Natural Science Foundation of China (grant number:82002539)the Natural Science Foundation of Shanghai (grant number:19ZR1447700)+2 种基金the Health System Innovation Project of Shanghai Putuo Science and Technology Commission (grant numbers:PTKWWS201903)The Yangfan Plan of Shanghai Science and Technology Commission (grant no.21YF1435400)Shanghai Municipal Health Commission,China (grant no.201840233).
文摘Metabolic-associated fatty liver disease(MAFLD)is a new disease definition,and is proposed to replace the previous name,nonalcoholic fatty liver disease(NAFLD).Globally,MAFLD/NAFLD is the most common liver disease,with an incidence rate ranging from 6%to 35%in adult populations.The pathogenesis of MAFLD/NAFLD is closely related to insulin resistance(IR),and the genetic susceptibility to acquired metabolic stress-associated liver injury.Similarly,the gut microbiota in MAFLD/NAFLD is being revaluated by scientists,as the gut and liver influence each other via the gut-liver axis.Ferroptosis is a novel form of programmed cell death caused by iron-dependent lipid peroxidation.Emerging evidence suggests that ferroptosis has a key role in the pathological progression of MAFLD/NAFLD,and inhibition of ferroptosis may become a novel therapeutic strategy for the treatment of NAFLD.This review focuses on the main mechanisms behind the promotion of MAFLD/NAFLD occurrence and development by the intestinal microbiota and ferroptosis.It outlines new strategies to target the intestinal microbiota and ferroptosis to facilitate future MAFLD/NAFLD therapies.
基金supported by grants from Natural Science Foundation of Jiangsu Province,China(No.BK20211105)the Key Research and Development Plan of Jiangsu Province,China(No.BE2019692)+2 种基金the Health Project of Jiangsu Province,China(No.H2019072)the Social Development Foundation of Nantong City,China(No.MS22020005,JCZ21061,MSZ20076 and JCZ20065)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(No.KYCX20_2673,KYCX20_2681 and KYCX21_3112).
文摘Exosomes carry and transmit signaling molecules used for intercellular communication.The generation and secretion of exosomes is a multistep interlocking process that allows simultaneous control of multiple regulatory sites.Protein molecules,mainly RAB GTPases,cytoskeletal proteins and soluble N-ethylmaleimide-sensitive fusion attachment protein receptor(SNARE),are specifically regulated in response to pathological conditions such as altered cellular microenvironment,stimulation by pathogenic factors,or gene mutation.This interferes with the smooth functioning of endocytosis,translocation,degradation,docking and fusion processes,leading to changes in the secretion of exosomes.Large numbers of secreted exosomes are disseminated by the flow of body fluids and absorbed by the recipient cells.By transmitting characteristic functional proteins and genetic information produced under disease conditions,exosomes can change the physiological state of the recipient cells and their microenvironment.The microenvironment,in turn,affects the occurrence and development of disease.Therefore,this review will discuss the mechanism by which exosome secretion is regulated in cells following the formation of mature secretory multivesicular bodies(MVBs).The overall aim is to find ways to eliminate disease-derived exosomes at their source,thereby providing an important new basis for the clinical treatment of disease.
基金This work was supported by the National Natural Science Foundation of China(No.21707077)the Special Fund of Beijing Key Laboratory of Indoor Air Quality Evaluation and Control(No.BZ0344KF20-06)the Fundamental Research Funds for the Central Universities(No.2020MS037).
文摘Surface-enhanced Raman scattering(SERS)has been used in atmospheric aerosol detection as it enables the high-resolution analysis of particulate matter.However,its use in the detection of historical samples without damaging the sampling membrane while achieving effective transfer and the high-sensitivity analysis of particulate matter from sample films remains challenging.In this study,a new type of SERS tape was developed,consisting of Au nanoparticles(NPs)on an adhesive double-sided Cu film(DCu).The enhanced electromagnetic field generated by the coupled resonance of the local surface plasmon resonances of AuNPs and DCu led to an enhanced SERS signal with an experimental enhancement factor of 10^(7).The AuNPs were semi-embedded and distributed on the substrate,and the viscous DCu layer was exposed,enabling particle transfer.The substrates exhibited good uniformity and favorable reproducibility with relative standard deviations of 13.53%and 9.74%respectively,and the substrates could be stored for 180 days with no signs of signal weakening.The application of the substrates was demonstrated by the extraction and detection of malachite green and ammonium salt particulate matter.The results demonstrated that SERS substrates based on AuNPs and DCu are highly promising in real–world environmental particle monitoring and detection.
基金The first author appreciates the financial support from Hunan Provincial Expressway Group Co.,Ltd.and the Hunan Department of Transportation(No.202152)in ChinaThe first author also appreciates the funding support from the National Natural Science Foundation of China(No.51778038)the Beijing high-level overseas talents in China.Any opinion,finding,and conclusion expressed in this paper are those of the authors and do not necessarily represent the view of any organization.
文摘Due to the rapid advancement of the transportation industry and the continual increase in pavement infrastructure,it is difficult to keep up with the huge road maintenance task by relying only on the traditional manual detection method.Intelligent pavement detection technology with deep learning techniques is available for the research and industry areas by the gradual development of computer vision technology.Due to the different characteristics of pavement distress and the uncertainty of the external environment,this kind of object detection technology for distress classification and location still faces great challenges.This paper discusses the development of object detection technology and analyzes classical convolutional neural network(CNN)architecture.In addition to the one-stage and two-stage object detection frameworks,object detection without anchor frames is introduced,which is divided according to whether the anchor box is used or not.This paper also introduces attention mechanisms based on convolutional neural networks and emphasizes the performance of these mechanisms to further enhance the accuracy of object recognition.Lightweight network architecture is introduced for mobile and industrial deployment.Since stereo cameras and sensors are rapidly developed,a detailed summary of three-dimensional object detection algorithms is also provided.While reviewing the history of the development of object detection,the scope of this review is not only limited to the area of pavement crack detection but also guidance for researchers in related fields is shared.
基金the 2020 Research Base Project of National Ethnic Affairs Commission of the PRC"Historical Investigation on the Formation,Spread and Cultivation of the Sense of Community for the Chinese Nation-Centering on the Manchurian,Mongolian and Tibetan Ethnic Groups"(2020-GMG-027)it is supported by the"Interdisciplinary Platform of Renmin University of China for Building the Sense of Community for the Chinese Nation"。
文摘In recent years,the concept"northern ethnic dynasties"has been widely used when referring to dynasties established by ethnic groups from northern China,including Liao,Jin,Yuan,and Qing dynasty.When it comes to the prolonged debates on the relation between ethnic groups and state,the traditional narrative of the dynastic history of Central Plains,which holds"sinicization"as its principal line,has been challenged;and the academia has been focusing on how to elaborate features and state forms of these northern ethnic dynasties.This article argues that,only by returning to the dynasty-based narrative of the evolvement of northern ethnic regimes,can we break the shackle of western-style"nation state"narrative;can we understand the fact that dynasticity transcends ethnicity in Chinese history;and can we thereby establish the correct view of history on the Chinese nation.
基金This work was supported by the National Natural Science Foundation of China(NSFC)under Grant No.52006210 and No.51722605and the Key Research and Development Program of Anhui Province under Grant No.201904a07020059The computational resources used in this work were provided by the Supercomputing Environment of Chinese Academy of Sciences(ScGrid).
文摘This paper has analyzed the asymmetric flow effect of fire-induced thermal flow in a horizontal tunnel under the natural ventilation condition by conducting large eddy simulations (LES). The key objective is to reveal and to have a better understanding of the asymmetric flow effect caused by the upstream and downstream tunnel length difference. The mechanism behind it can be explained based on the conservation of mass and dynamic force analysis on the smoke and fresh air. The strength of the asymmetric flow effect is characterized by the mass flow rate of the induced longitudinal flow (net mass flow rate of a cross-section). An empirical correlation to predict the induced longitudinal mass flow rate is proposed. Furthermore, the law of smoke and air flow distribution within a horizontal tunnel is established. The proportion of smoke (or air) flowing out (or coming in) through the opening increase (or decrease) linearly with the increasing distance between that opening to the fire location. The variation of the air flow with the longitudinal fire location in a tunnel is more sensitive than the smoke flow. Results have shown that as the fire approaches the tunnel exit from the middle of the tunnel, the smoke spilling out through this opening is reduced from 50% to 40%, while the fresh air incoming from this opening is increased from 50% to 100% and vice versa.
