Stroke-induced alterations in cerebral blood flow trigger neurovascular remodeling,as manifested by the blood-brain barrier dysfunction and subs equent neurovascular repair activities such as angiogenesis.This process...Stroke-induced alterations in cerebral blood flow trigger neurovascular remodeling,as manifested by the blood-brain barrier dysfunction and subs equent neurovascular repair activities such as angiogenesis.This process involves neurovascular communication that facilitates the transport of mediators among cerebrovascular endothelial cells,pericytes,glial cells,and neurons,thereby transmitting signals from donor to recipient cells to elicit a collaborative response.展开更多
Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using ...Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using the semi-analytical numerical method in this paper. The deflections and stresses of the plates are presented. Numerical results show the well accuracy and convergence of the method. Compared with the finite element method, the semi-analytical nu- merical method is with great advantage in the computational efficiency. Moreover, study on ax- isymmetric bending of two-directional functionally graded annular plate shows that such plates have better performance than those made of isotropic homogeneous materials or one-directional functionally graded materials. Two-directional functionally graded material is a potential alternative to the one-directional functionally graded material. And the integrated design of materials and structures can really be achieved in two-directional functionally graded materials.展开更多
Bulk flow model with perturbation simplification has been used to calculate rotordynamic coefficients in annular seals which have significant influences on the dynamic behavior of rotors in turbomachinery. In this wor...Bulk flow model with perturbation simplification has been used to calculate rotordynamic coefficients in annular seals which have significant influences on the dynamic behavior of rotors in turbomachinery. In this work, a transient bulk flow model with arbitrary rotor motion is developed, and the boundary conditions and friction factor in the model are calibrated with steady Computational Fluid Dynamics（CFD） analysis. The numerical solution scheme is developed based on the finite element method to obtain the transient reaction force in the seal clearance. With a periodic circular rotor orbit, the transient forces at multiple whirling frequencies are used to evaluate the rotordynamic coefficients. The leakage flowrate of CFD analysis has good agreement with experimental results and the calibrated parameters in bulk flow model are dependent on operating conditions. Although CFD calibration improves the accuracy of the perturbed bulk flow model, the direct damping is overestimated and the cross-coupled damping is underestimated. Compared with the perturbed model, the predictions of the transient bulk flow model are more agreeable with the experiment.展开更多
Accurate measurement of gas-liquid phase fraction is essential for the proper modelling of the pressure drop, heat transfer coefficient, mass transfer rate and interfacial area in two-phase flows. In this paper, takin...Accurate measurement of gas-liquid phase fraction is essential for the proper modelling of the pressure drop, heat transfer coefficient, mass transfer rate and interfacial area in two-phase flows. In this paper, taking the issue of optical distortion into account, an analytical model was proposed to estimate and correct the liquid holdup in gas-liquid annular flow through a circular pipe using high-speed camera method. The error in the liquid holdup measurement generated from different refractive indices among transparent circular pipe, liquid film and air core was firstly theoretically analyzed based on the geometric optics. Experimental tests were then carried out to identify the difference as well as to validate the proposed model. Results indicated that the prediction of the liquid holdup has a good performance with the experimental data(i.e., mean relative error is 4.1%) and the measured liquid holdup is larger than the real one. It was found that the measured liquid holdup is larger than the real one. Generally, when the real liquid holdup gets smaller, the discrepancy between the measured liquid holdup by image and the real liquid holdup becomes more significant. Thus, after measuring the liquid holdup from the images, the value of the measured liquid holdup must be corrected by the present model in order to obtain the real liquid holdup.展开更多
In this paper we use the Green function method to solve the problem of steady one dimensional flow of an incompressible viscous, electrically conducting fluid through a pipe with partial circular ring cross sec- tion ...In this paper we use the Green function method to solve the problem of steady one dimensional flow of an incompressible viscous, electrically conducting fluid through a pipe with partial circular ring cross sec- tion and one with annular cross section, in the presence of an applied transverse uniform magnetic field, We ob- tain analytic solutions and carry out some numerical calculations of the velocity distribution and induced magnet- ic field.展开更多
The development of sustainable sludge management systems requires looking at them with a new vision in which the concepts of SD(Sustainable Development)must integrate those of CE(Circular Economy),both concepts subjec...The development of sustainable sludge management systems requires looking at them with a new vision in which the concepts of SD(Sustainable Development)must integrate those of CE(Circular Economy),both concepts subject to the principles of TD(Thermodynamics),thus allowing the adoption of actions that are all the more effective the more complete the evaluation of the social dimension has been.This involves a new“Way of thinking”which sees the sludge system as the“Locomotive”of the entire wastewater/sludge treatment train and is developed through“Ways of acting”which includes both“Technical”actions to maximize recoveries of useful materials and/or or energy,and“Socio/Institutional”actions to overcome barriers linked to local cultures and traditions,also considering that the specific local context heavily influences the choices capable of satisfying the concepts of CE.It follows the need of issuing realistic and applicable regulations and overcoming social barriers,such as lack of infrastructure and/or qualified personnel,to achieve an effective integration of the concepts of CE with the more general ones of sustainability.展开更多
Urban areas worldwide face escalating challenges in managing municipal solid waste (MSW) due to rapid urbanization, population growth, and changing consumption patterns. Inefficient waste management systems contribute...Urban areas worldwide face escalating challenges in managing municipal solid waste (MSW) due to rapid urbanization, population growth, and changing consumption patterns. Inefficient waste management systems contribute to environmental degradation, public health risks, and resource depletion, underscoring the need for innovative solutions. This review employing AI-driven sorting technologies in urban waste management as a transformative framework for sustainable MSW management, emphasizing waste reduction, resource recovery, and closed-loop systems. The paper synthesizes existing literature, case studies, and technological advancements to explore strategies for integrating CE principles into MSW management. Key areas of focus include the application of emerging technologies such as artificial intelligence, machine learning, and big data analytics;advancements in waste-to-resource technologies;the development of scalable and adaptable CE models tailored to diverse urban contexts;and fostering collaboration among governments, private sectors, and communities. Findings highlight the potential of CE frameworks to minimize waste generation, enhance resource efficiency, and create resilient urban systems. However, significant barriers remain, including technological, financial, and policy challenges. The review concludes by identifying future research directions and actionable recommendations for stakeholders, aiming to advance the global transition toward sustainable urban waste management.展开更多
Quantitative phase imaging(QPI)enables non-invasive cellular analysis by utilizing cell thickness and refractive index as intrinsic probes,revolutionizing label-free microscopy in cellular research.Differential phase ...Quantitative phase imaging(QPI)enables non-invasive cellular analysis by utilizing cell thickness and refractive index as intrinsic probes,revolutionizing label-free microscopy in cellular research.Differential phase contrast(DPC),a non-interferometric QPI technique,requires only four intensity images under asymmetric illumination to recover the phase of a sample,offering the advantages of being label-free,non-coherent and highly robust.Its phase reconstruction result relies on precise modeling of the phase transfer function(PTF).However,in real optical systems,the PTF will deviate from its theoretical ideal due to the unknown wavefront aberrations,which will lead to significant artifacts and distortions in the reconstructed phase.We propose an aberration-corrected DPC(ACDPC)method that utilizes three intensity images under annular illumination to jointly retrieve the aberration and the phase,achieving high-quality QPI with minimal raw data.By employing three annular illuminations precisely matched to the numerical aperture of the objective lens,the object information is transmitted into the acquired intensity with a high signal-to-noise ratio.Phase retrieval is achieved by an iterative deconvolution algorithm that uses simulated annealing to estimate the aberration and further employs regularized deconvolution to reconstruct the phase,ultimately obtaining a refined complex pupil function and an aberration-corrected quantitative phase.We demonstrate that ACDPC is robust to multi-order aberrations without any priori knowledge,and can effectively retrieve and correct system aberrations to obtain high-quality quantitative phase.Experimental results show that ACDPC can clearly reproduce subcellular structures such as vesicles and lipid droplets with higher resolution than conventional DPC,which opens up new possibilities for more accurate subcellular structure analysis in cell biology.展开更多
Obtaining residual stress is crucial for controlling the machining deformation in annular parts,and can directly influence the performance and stability of key components in advanced equipment.Since existing research ...Obtaining residual stress is crucial for controlling the machining deformation in annular parts,and can directly influence the performance and stability of key components in advanced equipment.Since existing research has achieved global residual stress field inference for components by using the deformation force-based method where the deformation force is monitored during the machining process,reliable acquisition of deformation force stll remains a significant challenge under complex machining conditions.This paper proposes a hierarchical optimization method for the layout of deformation force monitoring of annular parts.The proposed method establishes two optimization objectives by analyzing the relationship between the deformation force and the residual stress in annular parts,i.e.,equivalence and ilconditioning of solving process.Specifically,the equivalence of the monitored deformation force and residual stress in terms of effect on caused machining deformation is evaluated by local deformation,and the illconditioning is also optimized to enhance the stability of residual stress inference.Verification is implemented in both simulation and actual machining experiments,demonstrating effectiveness of the proposed layout optimization method in inferring residual stress field of annular parts with deformation force.展开更多
To address the challenges of varied aircraft skin hole detection types and susceptibility to noise,this paper proposes a method based on the perspective of dual contour edge information fusion.The core method combines...To address the challenges of varied aircraft skin hole detection types and susceptibility to noise,this paper proposes a method based on the perspective of dual contour edge information fusion.The core method combines stereoscopic vision and structured light dual contour information consistently,focusing on extracting edge point information around the hole edge to achieve precise detection of circular holes.In this approach,a line multi-directional gradient feature detector (LMGFD) is introduced for locating the holes from plane stereoscopic image.Furthermore,we establish a three-dimensional (3D) circular hole detection method (BPCircle) based on the dual contour edge information fusion.Finally,experiments demonstrate that our proposed method achieves superior accuracy and robustness based on public benchmark dataset and our own collected standard IPCDS dataset (including two-dimensional (2D)images,3D point clouds,and measured data of three-coordinate measuring machine).The dataset and code can be found from https://github.com/Nicholsdqw/123.展开更多
In concentric annular pipes,the difference in curvature between the inner and outer wall surfaces creates significant variations in the heat transfer characteristics of the two surfaces.The simplifications of the Ditt...In concentric annular pipes,the difference in curvature between the inner and outer wall surfaces creates significant variations in the heat transfer characteristics of the two surfaces.The simplifications of the Dittus-Boelter equation for circular pipes make it unsuitable for the complex flow induced by the geometry and heat transfer coupling effects in annular pipes.This prevents it from accurately predicting the turbulent heat transfer in concentric annular pipes.This paper used realizableκ–εand low Reynolds number models to conduct numerical simulations of turbulent convective heat transfer in concentric annular pipes and circular pipes.The results indicated that the local heat transfer coefficient and Nusselt number of the inner wall surface of the annular pipe were both higher than those of the outer wall surface.The Darcy resistance coefficient decreased upon increasing the Reynolds number and increased with the inner diameter-to-outer diameter ratio.When using the equivalent diameter as the characteristic scale,the turbulent heat transfer correlation obtained from circular pipes produced significant errors when used to approximate the turbulent convective heat transfer in concentric annular pipes.This error was greater for the inner wall surface,especially when the inner and outer diameters were relatively small,as the Nusselt number error on the inner wall surface reached 60.62%.The error of the Nusselt number on the outer wall surface reached 19.51%.展开更多
BACKGROUND:Circulating biomarkers for sepsis are lacking,and research on circular RNAs(circR NAs)as potential biomarkers of pneumonia-induced sepsis is limited.This study aims to investigate the diagnostic and prognos...BACKGROUND:Circulating biomarkers for sepsis are lacking,and research on circular RNAs(circR NAs)as potential biomarkers of pneumonia-induced sepsis is limited.This study aims to investigate the diagnostic and prognostic potential of circRNAs in patients with pneumonia-induced sepsis.METHODS:This prospective cohort study included 40 healthy individuals,60 patients with pneumonia,and 80 patients with pneumonia-induced sepsis.CircRNAs identified through RNA-sequencing were validated using quantitative real-time polymerase chain reaction(qRT-PCR).Spearman correlation analysis was used to evaluate the associations between circRNAs,inflammatory markers,Sequential Organ Failure Assessment(SOFA)scores,and Acute Physiology and Chronic Health EvaluationⅡ(APACHEⅡ)scores.Receiver operating characteristic(ROC)curves analysis were used to assess the diagnostic performance of circRNAs,while ROC curves and Kaplan-Meier survival analysis were used to evaluate their prognostic value of 28-day mortality.RESULTS:qRT-PCR confirmed the significant upregulation of Circ-CTD-2281E23.2 and downregulation of Circ-0075723 and Circ-0008679 in sepsis patients.Spearman correlation analysis showed that Circ-CTD-2281E23.2 was positively correlated with inflammatory markers and severity scores,whereas Circ-0075723 and Circ-0008679 were negatively correlated with these parameters.The area under the curve(AUC)values for Circ-CTD-2281E23.2,Circ-0075723,and Circ-0008679 in diagnosing pneumonia-induced sepsis were 0.728,0.706,and 0.793,respectively.The combination of these circRNAs(AUC=0.846)and the combination with other clinical indicators(AUC=0.990)demostrated enhanced AUC values.The AUC values for Circ-CTD-2281E23.2 and Circ-0075723 in predicting 28-day mortality were 0.664 and 0.765,respectively.CONCLUSION:This study suggest the additional diagnostic and prognostic value of circRNAs in pneumonia-induced sepsis.Circ-CTD-2281E23.2,Circ-0075723,and Circ-0008679 exhibit diagnostic potential,with Circ-CTD-2281E23.2 and Circ-0075723 showing positive prognostic value for 28-day mortality in sepsis patients.展开更多
Active matter exhibits collective motions at various scales.Geometric confinement has been identified as an effective way to control and manipulate active fluids,with much attention given to external factors.However,t...Active matter exhibits collective motions at various scales.Geometric confinement has been identified as an effective way to control and manipulate active fluids,with much attention given to external factors.However,the impact of the inherent properties of active particles on collective motion under confined conditions remains elusive.Here,we use a highly tunable active nematics model to study active systems under confinement,focusing on the effect of the self-driven speed of active particles.We identify three distinct states characterized by unique particle and flow fields within confined active nematic systems,among which circular rotation emerges as a collective motion involving rotational movement in both particle and flow fields.The theoretical phase diagram shows that increasing the self-driven speed of active particles significantly enhances the region of the circular rotation state and improves its stability.Our results provide insights into the formation of high quality vortices in confined active nematic systems.展开更多
Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid syste...Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid systems are mostly based on single-column platforms such as spars(single coaxial-cylinder hybrid system'hereafter).Systems based on multiple-column platforms such as semi-submersible platforms('multiple coaxial-cylinder hybrid systems'hereafter)are rarely seen or studied,despite their superiority in wave-power absorption due to the use of multiple WECs as well as in dynamic stability.This paper proposes a novel WindFloat-annular-WEC hybrid system,based on our study investigating its dynamic and power features,and optimizing the geometry and power take-off of the WECs.Our results show that the dynamic and power features of a multiple coaxial-cylinder hybrid system are different from those of a single coaxial-cylinder hybrid system,so the same optimization parameters cannot be directly applied.Flatter annular WECs absorb slightly more power in a wider wave-period range,but their geometry is confined by limitations in installation and structural strength.The overall effect of an oblique incident wave is greater intensity in the motions of the hybrid system in yaw and the direction perpendicular to propagation,although the difference is small and maybe negligible.展开更多
Layered rock formations are frequently encountered during the excavation of underground structures. The stability of such structures is influenced not only by the stress concentration caused by the cavities in the str...Layered rock formations are frequently encountered during the excavation of underground structures. The stability of such structures is influenced not only by the stress concentration caused by the cavities in the strata but also by the anisotropy of the layered rock mass. The interaction between them can lead to critical structural failure, such as rupture, collapse, or significant deformation within the adjacent rock mass, thereby jeopardizing operational safety. However, the coupling law and mechanism between the stress concentration resulting from the cavities and the anisotropy of a layered rock mass remain unclear. In this study, a uniaxial compression test was performed on shale specimens containing a circular hole to investigate the effects of layer inclination and circular holes on the mechanical properties, elastic energy storage, and failure behaviors of these specimens. The failure mechanism of the rock surrounding the hole was analyzed on the basis of the single plane of weakness theory and the Kirsch solution. The test results indicated pronounced anisotropy in the compressive strength, elastic modulus, and elastic strain energy of the specimens, with distinct “V”, “M” and “U”-shaped patterns correlated with varying layer inclination angles. In addition, the combined effect of stress concentration and layer inclination resulted in different failure types, which were classified into four groups according to their failure behavior. Theoretical analysis revealed that failure around circular holes in layered rock is affected by a range of variables, such as layer inclination, layer strength, lateral pressure coefficient, azimuth, and loading stress.展开更多
Sustainable alternatives have grown more prevalent due to an urgent need to address climate change,environmental degradation,and the depletion of non-renewable resources.As an inexhaustible and renewable resource,biom...Sustainable alternatives have grown more prevalent due to an urgent need to address climate change,environmental degradation,and the depletion of non-renewable resources.As an inexhaustible and renewable resource,biomass has become an attractive option for energy production within the framework of a circular economy that emphasizes resource efficiency and environmental sustainability.Various kinds and sources of biomass,from forestry waste and agricultural residue to animal dung and microalgae,are fully explored in this mini review,along with their potential for biofuel production in both developed and developing countries.The processes for thermochemical and biochemical conversion,the sustainability of using biomass,and the socioeconomic advantages,especially for African countries,are highlighted.Key case studies demonstrating the value and potential of biomass waste in promoting sustainable energy transitions worldwide are also discussed in this review.Despite its potential,the use of biomass is restricted due to challenges including low conversion efficiency,high transportation costs,seasonal variability,and insufficient advancements in technology.Nonetheless,biomass offers an innovative approach for developing an environmentally friendly,efficient,and low-carbon economy that promotes sustainable development and energy security.Holistic approaches,such as increased regional cooperation,capacity building,technical innovation,and policy reform,must be implemented to address existing challenges.展开更多
Circular RNAs(circRNAs)are a distinct type of nonlinear and noncoding RNAs endogenously expressed by pre-mRNA back-splicing and crucial in transcriptional and posttranscriptional regulation.CircRNAs can regulate cellu...Circular RNAs(circRNAs)are a distinct type of nonlinear and noncoding RNAs endogenously expressed by pre-mRNA back-splicing and crucial in transcriptional and posttranscriptional regulation.CircRNAs can regulate cellular and molecular pathways through various mechanisms,such as microRNA sponging.Numerous studies have indicated the regulatory roles of circRNAs in the osteogenic differentiation of stem cells(SCs)isolated from different sources.Dental tissue-derived mesenchymal SCs(MSCs)have received considerable attention in artificial bone engineering,in which SCs are used to manufacture functional bone tissues to repair bone defects.Recently,studies have reported the regulatory roles of circRNAs in the osteogenic differentiation of dental-derived MSCs,such as apical papillae,dental pulp,and dental follicle SCs.This review aimed to discuss the findings of studies evaluating the contribution of circRNAs to the osteogenic differentiation of dental-derived MSCs.展开更多
Owing to eccentricity and inclination, circularity of a cylindrical workpiece cannot be measured precisely by a circularity measuring machine when the workpiece has a small dimension(diameter ≤ 3 mm). In this paper, ...Owing to eccentricity and inclination, circularity of a cylindrical workpiece cannot be measured precisely by a circularity measuring machine when the workpiece has a small dimension(diameter ≤ 3 mm). In this paper, with the aim of solving this problem, circularity metrology of a small cylindrical workpiece using a segmenting scanning method is analyzed. The cross-sectional circle of the cylinder is segmented into several equivalent arcs for measurement by a two-dimensional coordinate measuring machine(profilometer). The circularity contour is obtained by stitching together arc contours obtained by data processing of the coordinates. Different segmenting patterns for coordinate scanning are considered. Measurement results are presented for three segmentation patterns, with 8, 10, and 12 equal segments, respectively.These results are evaluated in terms of the matching coefficient between neighboring arc contours on circumferential stitching, the Euclidean distance between neighboring arc contours on radial stitching, and the curvature of the arcs. From these evaluations, it is found that as the number of segments is increased, the matching coefficient increases from 0.14 to 0.50, the Euclidean distance decreases from 32 nm to 26 nm,and the curvature becomes close to the standard value.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82171344(to ZY),82471313(to CKT)the Guangdong Basic and Applied Basic Research Foundation,China,Nos.2023B1515120035,2024A1515012035(to CKT)The Science and Technology Projects in Guangzhou Nos.2025A03J4169(to ZY)。
文摘Stroke-induced alterations in cerebral blood flow trigger neurovascular remodeling,as manifested by the blood-brain barrier dysfunction and subs equent neurovascular repair activities such as angiogenesis.This process involves neurovascular communication that facilitates the transport of mediators among cerebrovascular endothelial cells,pericytes,glial cells,and neurons,thereby transmitting signals from donor to recipient cells to elicit a collaborative response.
基金Project supported by the National Natural Science Foundation of China (No.10432030).
文摘Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using the semi-analytical numerical method in this paper. The deflections and stresses of the plates are presented. Numerical results show the well accuracy and convergence of the method. Compared with the finite element method, the semi-analytical nu- merical method is with great advantage in the computational efficiency. Moreover, study on ax- isymmetric bending of two-directional functionally graded annular plate shows that such plates have better performance than those made of isotropic homogeneous materials or one-directional functionally graded materials. Two-directional functionally graded material is a potential alternative to the one-directional functionally graded material. And the integrated design of materials and structures can really be achieved in two-directional functionally graded materials.
基金supported by the National Natural Science Foundation of China(No.11176010)
文摘Bulk flow model with perturbation simplification has been used to calculate rotordynamic coefficients in annular seals which have significant influences on the dynamic behavior of rotors in turbomachinery. In this work, a transient bulk flow model with arbitrary rotor motion is developed, and the boundary conditions and friction factor in the model are calibrated with steady Computational Fluid Dynamics（CFD） analysis. The numerical solution scheme is developed based on the finite element method to obtain the transient reaction force in the seal clearance. With a periodic circular rotor orbit, the transient forces at multiple whirling frequencies are used to evaluate the rotordynamic coefficients. The leakage flowrate of CFD analysis has good agreement with experimental results and the calibrated parameters in bulk flow model are dependent on operating conditions. Although CFD calibration improves the accuracy of the perturbed bulk flow model, the direct damping is overestimated and the cross-coupled damping is underestimated. Compared with the perturbed model, the predictions of the transient bulk flow model are more agreeable with the experiment.
基金the National Natural Science Foundation of China(No.51276140)
文摘Accurate measurement of gas-liquid phase fraction is essential for the proper modelling of the pressure drop, heat transfer coefficient, mass transfer rate and interfacial area in two-phase flows. In this paper, taking the issue of optical distortion into account, an analytical model was proposed to estimate and correct the liquid holdup in gas-liquid annular flow through a circular pipe using high-speed camera method. The error in the liquid holdup measurement generated from different refractive indices among transparent circular pipe, liquid film and air core was firstly theoretically analyzed based on the geometric optics. Experimental tests were then carried out to identify the difference as well as to validate the proposed model. Results indicated that the prediction of the liquid holdup has a good performance with the experimental data(i.e., mean relative error is 4.1%) and the measured liquid holdup is larger than the real one. It was found that the measured liquid holdup is larger than the real one. Generally, when the real liquid holdup gets smaller, the discrepancy between the measured liquid holdup by image and the real liquid holdup becomes more significant. Thus, after measuring the liquid holdup from the images, the value of the measured liquid holdup must be corrected by the present model in order to obtain the real liquid holdup.
文摘In this paper we use the Green function method to solve the problem of steady one dimensional flow of an incompressible viscous, electrically conducting fluid through a pipe with partial circular ring cross sec- tion and one with annular cross section, in the presence of an applied transverse uniform magnetic field, We ob- tain analytic solutions and carry out some numerical calculations of the velocity distribution and induced magnet- ic field.
文摘The development of sustainable sludge management systems requires looking at them with a new vision in which the concepts of SD(Sustainable Development)must integrate those of CE(Circular Economy),both concepts subject to the principles of TD(Thermodynamics),thus allowing the adoption of actions that are all the more effective the more complete the evaluation of the social dimension has been.This involves a new“Way of thinking”which sees the sludge system as the“Locomotive”of the entire wastewater/sludge treatment train and is developed through“Ways of acting”which includes both“Technical”actions to maximize recoveries of useful materials and/or or energy,and“Socio/Institutional”actions to overcome barriers linked to local cultures and traditions,also considering that the specific local context heavily influences the choices capable of satisfying the concepts of CE.It follows the need of issuing realistic and applicable regulations and overcoming social barriers,such as lack of infrastructure and/or qualified personnel,to achieve an effective integration of the concepts of CE with the more general ones of sustainability.
文摘Urban areas worldwide face escalating challenges in managing municipal solid waste (MSW) due to rapid urbanization, population growth, and changing consumption patterns. Inefficient waste management systems contribute to environmental degradation, public health risks, and resource depletion, underscoring the need for innovative solutions. This review employing AI-driven sorting technologies in urban waste management as a transformative framework for sustainable MSW management, emphasizing waste reduction, resource recovery, and closed-loop systems. The paper synthesizes existing literature, case studies, and technological advancements to explore strategies for integrating CE principles into MSW management. Key areas of focus include the application of emerging technologies such as artificial intelligence, machine learning, and big data analytics;advancements in waste-to-resource technologies;the development of scalable and adaptable CE models tailored to diverse urban contexts;and fostering collaboration among governments, private sectors, and communities. Findings highlight the potential of CE frameworks to minimize waste generation, enhance resource efficiency, and create resilient urban systems. However, significant barriers remain, including technological, financial, and policy challenges. The review concludes by identifying future research directions and actionable recommendations for stakeholders, aiming to advance the global transition toward sustainable urban waste management.
基金supported by the National Natural Science Foundation of China(62305162,62227818,62361136588)China Postdoctoral Science Foundation(2023TQ0160,2023M731683)+5 种基金Nanjing University of Science and Technology independent research project(30923010305)National Key Research and Development Program of China(2024YFE0101300)Biomedical Competition Foundation of Jiangsu Province(BE2022847)Key National Industrial Technology Cooperation Foundation of Jiangsu Province(BZ2022039)Fundamental Research Funds for the Central Universities(2023102001)Open Research Fund of Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense(JSGP202105,JSGP202201,JSGPCXZNGZ202401)。
文摘Quantitative phase imaging(QPI)enables non-invasive cellular analysis by utilizing cell thickness and refractive index as intrinsic probes,revolutionizing label-free microscopy in cellular research.Differential phase contrast(DPC),a non-interferometric QPI technique,requires only four intensity images under asymmetric illumination to recover the phase of a sample,offering the advantages of being label-free,non-coherent and highly robust.Its phase reconstruction result relies on precise modeling of the phase transfer function(PTF).However,in real optical systems,the PTF will deviate from its theoretical ideal due to the unknown wavefront aberrations,which will lead to significant artifacts and distortions in the reconstructed phase.We propose an aberration-corrected DPC(ACDPC)method that utilizes three intensity images under annular illumination to jointly retrieve the aberration and the phase,achieving high-quality QPI with minimal raw data.By employing three annular illuminations precisely matched to the numerical aperture of the objective lens,the object information is transmitted into the acquired intensity with a high signal-to-noise ratio.Phase retrieval is achieved by an iterative deconvolution algorithm that uses simulated annealing to estimate the aberration and further employs regularized deconvolution to reconstruct the phase,ultimately obtaining a refined complex pupil function and an aberration-corrected quantitative phase.We demonstrate that ACDPC is robust to multi-order aberrations without any priori knowledge,and can effectively retrieve and correct system aberrations to obtain high-quality quantitative phase.Experimental results show that ACDPC can clearly reproduce subcellular structures such as vesicles and lipid droplets with higher resolution than conventional DPC,which opens up new possibilities for more accurate subcellular structure analysis in cell biology.
基金supported in part by the General Program of the National Natural Science Foundation of China(No.52175467)the National Key R&D Program of China(No.2022YFB3402600).
文摘Obtaining residual stress is crucial for controlling the machining deformation in annular parts,and can directly influence the performance and stability of key components in advanced equipment.Since existing research has achieved global residual stress field inference for components by using the deformation force-based method where the deformation force is monitored during the machining process,reliable acquisition of deformation force stll remains a significant challenge under complex machining conditions.This paper proposes a hierarchical optimization method for the layout of deformation force monitoring of annular parts.The proposed method establishes two optimization objectives by analyzing the relationship between the deformation force and the residual stress in annular parts,i.e.,equivalence and ilconditioning of solving process.Specifically,the equivalence of the monitored deformation force and residual stress in terms of effect on caused machining deformation is evaluated by local deformation,and the illconditioning is also optimized to enhance the stability of residual stress inference.Verification is implemented in both simulation and actual machining experiments,demonstrating effectiveness of the proposed layout optimization method in inferring residual stress field of annular parts with deformation force.
基金supported by the National Natural Science Foundation Youth (No.62303330)。
文摘To address the challenges of varied aircraft skin hole detection types and susceptibility to noise,this paper proposes a method based on the perspective of dual contour edge information fusion.The core method combines stereoscopic vision and structured light dual contour information consistently,focusing on extracting edge point information around the hole edge to achieve precise detection of circular holes.In this approach,a line multi-directional gradient feature detector (LMGFD) is introduced for locating the holes from plane stereoscopic image.Furthermore,we establish a three-dimensional (3D) circular hole detection method (BPCircle) based on the dual contour edge information fusion.Finally,experiments demonstrate that our proposed method achieves superior accuracy and robustness based on public benchmark dataset and our own collected standard IPCDS dataset (including two-dimensional (2D)images,3D point clouds,and measured data of three-coordinate measuring machine).The dataset and code can be found from https://github.com/Nicholsdqw/123.
基金Supported by the Major Program of the National Natural Science Foundation of China(Grant No.51736007).
文摘In concentric annular pipes,the difference in curvature between the inner and outer wall surfaces creates significant variations in the heat transfer characteristics of the two surfaces.The simplifications of the Dittus-Boelter equation for circular pipes make it unsuitable for the complex flow induced by the geometry and heat transfer coupling effects in annular pipes.This prevents it from accurately predicting the turbulent heat transfer in concentric annular pipes.This paper used realizableκ–εand low Reynolds number models to conduct numerical simulations of turbulent convective heat transfer in concentric annular pipes and circular pipes.The results indicated that the local heat transfer coefficient and Nusselt number of the inner wall surface of the annular pipe were both higher than those of the outer wall surface.The Darcy resistance coefficient decreased upon increasing the Reynolds number and increased with the inner diameter-to-outer diameter ratio.When using the equivalent diameter as the characteristic scale,the turbulent heat transfer correlation obtained from circular pipes produced significant errors when used to approximate the turbulent convective heat transfer in concentric annular pipes.This error was greater for the inner wall surface,especially when the inner and outer diameters were relatively small,as the Nusselt number error on the inner wall surface reached 60.62%.The error of the Nusselt number on the outer wall surface reached 19.51%.
基金supported by grants from the municipal Natural Science Foundation of Shanghai Scientific Committee of China(22ZR1451000 to TL)the peak supporting clinical discipline of Shanghai Health Bureau(2023ZDFC0104 to TL)+3 种基金the key clinical discipline of Shanghai Pudong Health Bureau(PWZxk2022-17 to TL)the clinical peak discipline of Shanghai Pudong Heath Bureau(PWYgf2021-03)the top-notch innovative medical talents of Shanghai Pudong Health Bureau(2025PDWSYCBJ-03 to TL)the leading medical talent project of Shanghai Pudong Heath Bureau(PWR12020-07 to LS)。
文摘BACKGROUND:Circulating biomarkers for sepsis are lacking,and research on circular RNAs(circR NAs)as potential biomarkers of pneumonia-induced sepsis is limited.This study aims to investigate the diagnostic and prognostic potential of circRNAs in patients with pneumonia-induced sepsis.METHODS:This prospective cohort study included 40 healthy individuals,60 patients with pneumonia,and 80 patients with pneumonia-induced sepsis.CircRNAs identified through RNA-sequencing were validated using quantitative real-time polymerase chain reaction(qRT-PCR).Spearman correlation analysis was used to evaluate the associations between circRNAs,inflammatory markers,Sequential Organ Failure Assessment(SOFA)scores,and Acute Physiology and Chronic Health EvaluationⅡ(APACHEⅡ)scores.Receiver operating characteristic(ROC)curves analysis were used to assess the diagnostic performance of circRNAs,while ROC curves and Kaplan-Meier survival analysis were used to evaluate their prognostic value of 28-day mortality.RESULTS:qRT-PCR confirmed the significant upregulation of Circ-CTD-2281E23.2 and downregulation of Circ-0075723 and Circ-0008679 in sepsis patients.Spearman correlation analysis showed that Circ-CTD-2281E23.2 was positively correlated with inflammatory markers and severity scores,whereas Circ-0075723 and Circ-0008679 were negatively correlated with these parameters.The area under the curve(AUC)values for Circ-CTD-2281E23.2,Circ-0075723,and Circ-0008679 in diagnosing pneumonia-induced sepsis were 0.728,0.706,and 0.793,respectively.The combination of these circRNAs(AUC=0.846)and the combination with other clinical indicators(AUC=0.990)demostrated enhanced AUC values.The AUC values for Circ-CTD-2281E23.2 and Circ-0075723 in predicting 28-day mortality were 0.664 and 0.765,respectively.CONCLUSION:This study suggest the additional diagnostic and prognostic value of circRNAs in pneumonia-induced sepsis.Circ-CTD-2281E23.2,Circ-0075723,and Circ-0008679 exhibit diagnostic potential,with Circ-CTD-2281E23.2 and Circ-0075723 showing positive prognostic value for 28-day mortality in sepsis patients.
基金supported by the National Key Research and Development Program of China under Grant No.2022YFA1405000Innovation Program for Quantum Science and Technology under Grant No.2024ZD0300101the National Natural Science Foundation of China under Grant Nos.12274212,12174184,12347102。
文摘Active matter exhibits collective motions at various scales.Geometric confinement has been identified as an effective way to control and manipulate active fluids,with much attention given to external factors.However,the impact of the inherent properties of active particles on collective motion under confined conditions remains elusive.Here,we use a highly tunable active nematics model to study active systems under confinement,focusing on the effect of the self-driven speed of active particles.We identify three distinct states characterized by unique particle and flow fields within confined active nematic systems,among which circular rotation emerges as a collective motion involving rotational movement in both particle and flow fields.The theoretical phase diagram shows that increasing the self-driven speed of active particles significantly enhances the region of the circular rotation state and improves its stability.Our results provide insights into the formation of high quality vortices in confined active nematic systems.
基金supported by the National Natural Science Foundation of China(Nos.52201322,52222109,and 52071096)the Guangdong Basic and Applied Basic Research Foundation(Nos.2022B1515020036 and 2023A1515012144)the Natural Science Foundation of Guangzhou City(No.202201010055),China.
文摘Installing annular wave-energy converters(WECs)on the columns of floating wind platforms in the form of a coaxial-cylinder provides a convenient means of integration.Extant coaxial-cylinder-type wind-wave hybrid systems are mostly based on single-column platforms such as spars(single coaxial-cylinder hybrid system'hereafter).Systems based on multiple-column platforms such as semi-submersible platforms('multiple coaxial-cylinder hybrid systems'hereafter)are rarely seen or studied,despite their superiority in wave-power absorption due to the use of multiple WECs as well as in dynamic stability.This paper proposes a novel WindFloat-annular-WEC hybrid system,based on our study investigating its dynamic and power features,and optimizing the geometry and power take-off of the WECs.Our results show that the dynamic and power features of a multiple coaxial-cylinder hybrid system are different from those of a single coaxial-cylinder hybrid system,so the same optimization parameters cannot be directly applied.Flatter annular WECs absorb slightly more power in a wider wave-period range,but their geometry is confined by limitations in installation and structural strength.The overall effect of an oblique incident wave is greater intensity in the motions of the hybrid system in yaw and the direction perpendicular to propagation,although the difference is small and maybe negligible.
基金supported by Beijing Natural Science Foundation of China(Grant No.2244099)the China Postdoctoral Science Foundation(Grant No.2023T0025)the National Natural Science Foundation of China(Grant No.52074020).
文摘Layered rock formations are frequently encountered during the excavation of underground structures. The stability of such structures is influenced not only by the stress concentration caused by the cavities in the strata but also by the anisotropy of the layered rock mass. The interaction between them can lead to critical structural failure, such as rupture, collapse, or significant deformation within the adjacent rock mass, thereby jeopardizing operational safety. However, the coupling law and mechanism between the stress concentration resulting from the cavities and the anisotropy of a layered rock mass remain unclear. In this study, a uniaxial compression test was performed on shale specimens containing a circular hole to investigate the effects of layer inclination and circular holes on the mechanical properties, elastic energy storage, and failure behaviors of these specimens. The failure mechanism of the rock surrounding the hole was analyzed on the basis of the single plane of weakness theory and the Kirsch solution. The test results indicated pronounced anisotropy in the compressive strength, elastic modulus, and elastic strain energy of the specimens, with distinct “V”, “M” and “U”-shaped patterns correlated with varying layer inclination angles. In addition, the combined effect of stress concentration and layer inclination resulted in different failure types, which were classified into four groups according to their failure behavior. Theoretical analysis revealed that failure around circular holes in layered rock is affected by a range of variables, such as layer inclination, layer strength, lateral pressure coefficient, azimuth, and loading stress.
文摘Sustainable alternatives have grown more prevalent due to an urgent need to address climate change,environmental degradation,and the depletion of non-renewable resources.As an inexhaustible and renewable resource,biomass has become an attractive option for energy production within the framework of a circular economy that emphasizes resource efficiency and environmental sustainability.Various kinds and sources of biomass,from forestry waste and agricultural residue to animal dung and microalgae,are fully explored in this mini review,along with their potential for biofuel production in both developed and developing countries.The processes for thermochemical and biochemical conversion,the sustainability of using biomass,and the socioeconomic advantages,especially for African countries,are highlighted.Key case studies demonstrating the value and potential of biomass waste in promoting sustainable energy transitions worldwide are also discussed in this review.Despite its potential,the use of biomass is restricted due to challenges including low conversion efficiency,high transportation costs,seasonal variability,and insufficient advancements in technology.Nonetheless,biomass offers an innovative approach for developing an environmentally friendly,efficient,and low-carbon economy that promotes sustainable development and energy security.Holistic approaches,such as increased regional cooperation,capacity building,technical innovation,and policy reform,must be implemented to address existing challenges.
文摘Circular RNAs(circRNAs)are a distinct type of nonlinear and noncoding RNAs endogenously expressed by pre-mRNA back-splicing and crucial in transcriptional and posttranscriptional regulation.CircRNAs can regulate cellular and molecular pathways through various mechanisms,such as microRNA sponging.Numerous studies have indicated the regulatory roles of circRNAs in the osteogenic differentiation of stem cells(SCs)isolated from different sources.Dental tissue-derived mesenchymal SCs(MSCs)have received considerable attention in artificial bone engineering,in which SCs are used to manufacture functional bone tissues to repair bone defects.Recently,studies have reported the regulatory roles of circRNAs in the osteogenic differentiation of dental-derived MSCs,such as apical papillae,dental pulp,and dental follicle SCs.This review aimed to discuss the findings of studies evaluating the contribution of circRNAs to the osteogenic differentiation of dental-derived MSCs.
基金supported by the National Defense Basic Scientific Research Program of China(Grant No.JCKY2019427D002).
文摘Owing to eccentricity and inclination, circularity of a cylindrical workpiece cannot be measured precisely by a circularity measuring machine when the workpiece has a small dimension(diameter ≤ 3 mm). In this paper, with the aim of solving this problem, circularity metrology of a small cylindrical workpiece using a segmenting scanning method is analyzed. The cross-sectional circle of the cylinder is segmented into several equivalent arcs for measurement by a two-dimensional coordinate measuring machine(profilometer). The circularity contour is obtained by stitching together arc contours obtained by data processing of the coordinates. Different segmenting patterns for coordinate scanning are considered. Measurement results are presented for three segmentation patterns, with 8, 10, and 12 equal segments, respectively.These results are evaluated in terms of the matching coefficient between neighboring arc contours on circumferential stitching, the Euclidean distance between neighboring arc contours on radial stitching, and the curvature of the arcs. From these evaluations, it is found that as the number of segments is increased, the matching coefficient increases from 0.14 to 0.50, the Euclidean distance decreases from 32 nm to 26 nm,and the curvature becomes close to the standard value.
