A fast and simple method to extract phase-contrast images from interferograms is proposed, and its effectiveness is demonstrated through simulation and experiment. For x-ray differential phase contrast imaging, a stro...A fast and simple method to extract phase-contrast images from interferograms is proposed, and its effectiveness is demonstrated through simulation and experiment. For x-ray differential phase contrast imaging, a strong attenuation signal acts as an overwhelming background intensity that obscures the weak phase signal so that no obvious phase-gradient information is detectable in the raw image. By subtracting one interferogram from another, chosen at particular intervals,the phase signal can be isolated and magnified.展开更多
X-ray grating interferometer has attracted widely attention in the past years due to its capability in achieving x-ray phase contrast imaging with low brilliance source. However, the widely used phase stepping informa...X-ray grating interferometer has attracted widely attention in the past years due to its capability in achieving x-ray phase contrast imaging with low brilliance source. However, the widely used phase stepping information extraction method reduces system stability and prolongs data acquisition time by several times compared with conventional x-ray absorption- based imaging. The mechanical stepping can be avoided by using a staggered grating, but at the cost of low vertical spatial resolution. In this paper, employing a modified staggered grating and the angular signal radiography, we proposed a single-shot grating-based x-ray differential phase contrast imaging with decent vertical spatial resolution. The theoretical framework was deduced and proved by numerical experiments. Absorption, phase, and scattering computed tomography can be performed without phase stepping. Therefore, we believe this fast and highly stable imaging method with decent resolution would be widely applied in x-ray grating-based phase contrast imaging.展开更多
Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interfe...Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interference devices(SQUID),MEG based on optically pump magnetometer(OPM)has the advantages of higher sensitivity,better spatial resolution and lower cost.However,most of the current studies are clinical studies,and there is a lack of animal studies on MEG based on OPM technology.Pain,a multifaceted sensory and emotional phenomenon,induces intricate alterations in brain activity,exhibiting notable sex differences.Despite clinical revelations of pain-related neuronal activity through MEG,specific properties remain elusive,and comprehensive laboratory studies on pain-associated brain activity alterations are lacking.The aim of this study was to investigate the effects of inflammatory pain(induced by Complete Freund’s Adjuvant(CFA))on brain activity in a rat model using the MEG technique,to analysis changes in brain activity during pain perception,and to explore sex differences in pain-related MEG signaling.Methods This study utilized adult male and female Sprague-Dawley rats.Inflammatory pain was induced via intraplantar injection of CFA(100μl,50%in saline)in the left hind paw,with control groups receiving saline.Pain behavior was assessed using von Frey filaments at baseline and 1 h post-injection.For MEG recording,anesthetized rats had an OPM positioned on their head within a magnetic shield,undergoing two 15-minute sessions:a 5-minute baseline followed by a 10-minute mechanical stimulation phase.Data analysis included artifact removal and time-frequency analysis of spontaneous brain activity using accumulated spectrograms,generating spectrograms focused on the 4-30 Hz frequency range.Results MEG recordings in anesthetized rats during resting states and hind paw mechanical stimulation were compared,before and after saline/CFA injections.Mechanical stimulation elevated alpha activity in both male and female rats pre-and post-saline/CFA injections.Saline/CFA injections augmented average power in both sexes compared to pre-injection states.Remarkably,female rats exhibited higher average spectral power 1 h after CFA injection than after saline injection during resting states.Furthermore,despite comparable pain thresholds measured by classical pain behavioral tests post-CFA treatment,female rats displayed higher average power than males in the resting state after CFA injection.Conclusion These results imply an enhanced perception of inflammatory pain in female rats compared to their male counterparts.Our study exhibits sex differences in alpha activities following CFA injection,highlighting heightened brain alpha activity in female rats during acute inflammatory pain in the resting state.Our study provides a method for OPM-based MEG recordings to be used to study brain activity in anaesthetized animals.In addition,the findings of this study contribute to a deeper understanding of pain-related neural activity and pain sex differences.展开更多
Dental mesenchymal stem cells(DMSCs)are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differen...Dental mesenchymal stem cells(DMSCs)are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differentiation potential and self-renewal ability.The cellular microenvironment regulates the fate of stem cells and can be modified using various optimization techniques.These methods can influence the cellular microenvironment,activate disparate signaling pathways,and induce different biological effects.“Epigenetic regulation”refers to the process of influencing gene expression and regulating cell fate without altering DNA sequences,such as histone methylation.Histone methylation modifications regulate pivotal transcription factors governing DMSCs differentiation into osteo-/odontogenic lineages.The most important sites of histone methylation in tooth organization were found to be H3K4,H3K9,and H3K27.Histone methylation affects gene expression and regulates stem cell differentiation by maintaining a delicate balance between major trimethylation sites,generating distinct chromatin structures associated with specific downstream transcriptional states.Several crucial signaling pathways associated with osteogenic differentiation are susceptible to modulation via histone methylation modifications.A deeper understanding of the regulatory mechanisms governing histone methylation modifications in osteo-/odontogenic differentiation and immune-inflammatory responses of DMSCs will facilitate further investigation of the epigenetic regulation of histone methylation in DMSC-mediated tissue regeneration and inflammation.Here is a concise overview of the pivotal functions of epigenetic histone methylation at H3K4,H3K9,and H3K27 in the regulation of osteo-/odontogenic differentiation and renewal of DMSCs in both non-inflammatory and inflammatory microenvironments.This review summarizes the current research on these processes in the context of tissue regeneration and therapeutic interventions.展开更多
Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this sys...Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this system,its economic feasibility,water usage effectiveness(WUE),and carbon usage effectiveness(CUE)remain underexplored.This study introduces a comprehensive evaluation index designed to assess the applicability of the rack-level loop thermosyphon system across various computing hub nodes.The air wet bulb temperature Ta,w was identified as the most significant factor influencing the variability in the combination of PUE,CUE,and WUE values.The results indicate that the rack-level loop thermosyphon system achieves the highest score in Lanzhou(94.485)and the lowest in Beijing(89.261)based on the comprehensive evaluation index.The overall ranking of cities according to the comprehensive evaluation score is as follows:Gansu hub(Lanzhou)>Inner Mongolia hub(Hohhot)>Ningxia hub(Yinchuan)>Yangtze River Delta hub(Shanghai)>Chengdu Chongqing hub(Chongqing)>Guangdong-Hong Kong-Macao Greater Bay Area hub(Guangzhou)>Guizhou hub(Guiyang)>Beijing-Tianjin-Hebei hub(Beijing).Furthermore,Hohhot,Lanzhou,and Yinchuan consistently rank among the top three cities for comprehensive scores across all load rates,while Guiyang(at a 25%load rate),Guangzhou(at a 50%load rate),and Beijing(at 75%and 100%load rates)exhibited the lowest comprehensive scores.展开更多
Reasonable greening design can effectively alleviate campus heat environment issues.This study uses the ENVI-met numerical model,along with in-situ observations and simulations,to analyze the thermal environment under...Reasonable greening design can effectively alleviate campus heat environment issues.This study uses the ENVI-met numerical model,along with in-situ observations and simulations,to analyze the thermal environment under three different greening schemes in typical areas of the Guangzhou University campus.The results indicate that the outdoor thermal environment is significantly influenced by the underlying surface materials and vegetation.The temperature of brick-paved surface is 0.9℃higher than that of natural soil surfaces under tree shade.Numerical simulations further confirm that increasing vegetation coverage effectively reduces outdoor air temperature.When the greening rate increases to 40%,the outdoor average temperature decreases by 0.7℃and relative humidity increases by approximately 4%,while wind speed remains minimal change.The cooling effect of vegetation is found to extend vertically to an altitude of 13 m.As the greening rate increases from 15%to 40%,the Mean Radiant Temperature(MRT)decreases from 50.6℃to 28.9℃,which is lower than the average ambient temperature,indicating improved thermal conditions.The Physiological Equivalent Temperature(PET)decreases from 40.2℃to 30.0℃,with the proportion of the areas classified as″very hot″reducing by 36.8%,significantly improving thermal comfort across most areas.Therefore,changing the ground material and greening landscape design can effectively alter the outdoor wind and thermal environment of the campus,thereby enhancing the thermal comfort for the campus community.展开更多
Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studie...Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studies on collective behavior in small animals such as fish and insects are well-established,similar research on large wild animals remains challenging due to the limited availability of sufficient and systematic field data.Here,we aimed to explore the collective decision-making pattern and its sexual difference for the dimorphic Tibetan antelopes Pantholops hodgsonii(chiru)in Xizang Autonomous Region,China,by analyzing individual leadership distribution,as well as the joining process,considering factors such as calving stages and joining ranks.The distinct correlations of decision participants’ratio with group size and decision duration underscore the trade-off between accuracy and speed in decision-making.Male antelopes display a more democratic decision-making pattern,while females exhibit more prompt responses after calving at an early stage.This study uncovers a partially shared decision-making strategy among Tibetan antelopes,suggesting flexible self-organization in group decision processes aligned with animal life cycle progression.展开更多
The release of essential nutrients from soil minerals for plant growth in calcareous soils,facilitated by organic extractants,is critical in semi-arid areas,particularly for elements affected by high soil pH.This stud...The release of essential nutrients from soil minerals for plant growth in calcareous soils,facilitated by organic extractants,is critical in semi-arid areas,particularly for elements affected by high soil pH.This study aims to investigate the release of calcium(Ca),magnesium(Mg),and phosphorus(P)through the application of wood vinegar extract in surface calcareous soils in Borojerd City,Lorestan Province,Iran.The experiment was conducted using a completely randomized design with three replications.The treatments included soils from three different land uses:vineyard,wheat field,and rangeland,each treated with 1.00%wood vinegar solution.Cumulative measurements of the specified elements were recorded over 10 consecutive 0.5 h intervals.The release data were analyzed using four various kinetic models(Elovich equation,parabolic diffusion law,power function equation,and zero-order kinetics).The highest concentrations recorded were for Ca(39,500.00 mg/kg),Mg(5880.00 mg/kg),and P(5.00 mg/kg)in grape cultivation.The findings revealed a significant difference in Ca release between grape cultivation and rangeland(P<0.01),while the Mg release showed a significant difference between both grape cultivation and rangeland and wheat cultivation(P<0.01).Additionally,the cumulative release of P showed significant differences between grape cultivation and both wheat and rangeland(P<0.01).The results indicated that the zero-order kinetics provided the best fit for the data(R^(2)=0.99).The maximum initial release amount was observed in grape cultivation when applying the zero-order kinetics,while the highest release rate was achieved using the parabolic diffusion law across three applications.Wood vinegar had the capacity to degrade various clay minerals,including vermiculite,smectite,palygorskite,and,to some extent,illite,resulting in the release of associated elements.Consequently,it can be concluded that wood vinegar can be effectively utilized in grape cultivation as an agent for reducing soil acidity,thereby enhancing the availability of soil nutrients and decreasing reliance on chemical fertilizers.展开更多
The main purpose of this paper is to try to find all entire solutions of the Fermat type difference-differential equation[p1(z)f(z+c)]^(2)+[p2(z)f(z)+p3(z)f′(z)]^(2)=p(z);or[p1(z)f(z)]^(2)+[p2(z)f′(z)+p3(z)f(z+c)]^(...The main purpose of this paper is to try to find all entire solutions of the Fermat type difference-differential equation[p1(z)f(z+c)]^(2)+[p2(z)f(z)+p3(z)f′(z)]^(2)=p(z);or[p1(z)f(z)]^(2)+[p2(z)f′(z)+p3(z)f(z+c)]^(2)=p(z)or[p1(z)f′(z)]^(2)+[p2(z)f(z+c)+p3(z)f(z)]^(2)=p(z);where c is a nonzero complex number,p1;p2 and p3 are polynomials in C satisfying p1p3■0;and p is a nonzero irreducible polynomial in C.展开更多
This paper explores the construction methods of“Same Course with Different Structures”curriculum resources based on knowledge graphs and their applications in the field of education.By reviewing the theoretical foun...This paper explores the construction methods of“Same Course with Different Structures”curriculum resources based on knowledge graphs and their applications in the field of education.By reviewing the theoretical foundations of knowledge graph technology,the“Same Course with Different Structures”teaching model,and curriculum resource construction,and integrating existing literature,the paper analyzes the methods for constructing curriculum resources using knowledge graphs.The research finds that knowledge graphs can effectively integrate multi-source data,support personalized teaching and precision education,and provide both a scientific foundation and technical support for the development of curriculum resources within the“Same Course with Different Structures”framework.展开更多
In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error...In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error between the numerical solution and the exact solution is obtained,and then compared with the error formed by the difference method,it is concluded that the Lagrange interpolation method is more effective in solving the variable coefficient ordinary differential equation.展开更多
Planetary surfaces,shaped by billions of years of geologic evolution,display numerous impact craters whose distribution of size,density,and spatial arrangement reveals the celestial body's history.Identifying thes...Planetary surfaces,shaped by billions of years of geologic evolution,display numerous impact craters whose distribution of size,density,and spatial arrangement reveals the celestial body's history.Identifying these craters is essential for planetary science and is currently mainly achieved with deep learning-driven detection algorithms.However,because impact crater characteristics are substantially affected by the geologic environment,surface materials,and atmospheric conditions,the performance of deep learning models can be inconsistent between celestial bodies.In this paper,we first examine how the surface characteristics of the Moon,Mars,and Earth,along with the differences in their impact crater features,affect model performance.Then,we compare crater detection across celestial bodies by analyzing enhanced convolutional neural networks and U-shaped Convolutional Neural Network-based models to highlight how geology,data,and model design affect accuracy and generalization.Finally,we address current deep learning challenges,suggest directions for model improvement,such as multimodal data fusion and cross-planet learning and list available impact crater databases.This review can provide necessary technical support for deep space exploration and planetary science,as well as new ideas and directions for future research on automatic detection of impact craters on celestial body surfaces and on planetary geology.展开更多
Understanding the complex relationship between vegetation change and both natural and anthropogenic factors is a subject of global importance.However,comprehensive explanations of vegetation cover trends across China...Understanding the complex relationship between vegetation change and both natural and anthropogenic factors is a subject of global importance.However,comprehensive explanations of vegetation cover trends across China’s different regions and the dynamic roles of their drivers remain limited.This study analyzed national and regional vegetation change trends from 2000 to 2020 and evaluated the evolving impacts of natural and anthropogenic factors.Results indicate that 44.14%of China’s land experienced significant increase(P<0.05)in vegetation coverage.The Northeast(A1),Southwest(A5),and South China(A8)regions showed extremely significant increases in vegetation cover,with over 65%of vegetation exhibiting extremely significant growth(P<0.01).In contrast,less than 25%of vegetation in Inner Mongolia(A2),Northwest(A3),and the Qinghai-Tibetan Plateau(A4)subregions demonstrated an extremely significant increasing trend(P<0.01).Precipitation(q=0.766)and land use type(q=0.636)were the most influential natural and anthropogenic factors,respectively,with their interaction(q=0.838)dominating national vegetation patterns.On the west side of the Hu Line,vegetation dynamics were mainly limited by arid and semi-arid climates,with precipitation as the dominant factor,though land use measures have contributed to some vegetation improvement.Between 2000 and 2020,the influence of precipitation on vegetation cover increased in regions A3 and A4,with q-values rising by 26.73%and 101.13%,respectively.Additionally,soil type exerted a significant effect(P<0.001)on vegetation cover across all regions,being most pronounced in A2(q=0.692).On the east side of the Hu Line,vegetation growth benefited generally from warm and humid conditions,while local decline in urbanized areas was largely attributable to land use change and economic expansion.Concurrently anthropogenic factors such as land use and population density increasingly influenced vegetation dynamics in eastern urban areas of the Hu Line.Population density and GDP were the most influential factors affecting vegetation cover in region A8,with q-values of 0.443 and 0.380,respectively(P<0.001).Future efforts should maintain the benefits of large-scale ecological projects and harmonize the relationship between urban vegetation and anthropogenic influences.展开更多
Improving the comprehensive performance of anion exchange membranes(AEMs)has a decisive impact on the wide application of anion exchange membrane fuel cells(AEMFCs).Herein,we prepared a series of new poly(phenanthrene...Improving the comprehensive performance of anion exchange membranes(AEMs)has a decisive impact on the wide application of anion exchange membrane fuel cells(AEMFCs).Herein,we prepared a series of new poly(phenanthrene-co-p-terphenyl piperidinium)(PPTP3F_(x)-DIL)AEMs with different fluorinated monomers for high performance AEMFCs.The polymerization of fluorinated monomers with other aryl monomers can effectively promote the separation of microphase in the membrane.It also has a high OH-conductivity at a low swelling.The membrane(PPTP3F_(4)-DIL)prepared by polycondensation of 2,2,2-trifluoro-1-(p-tolyl)ethan 1-one monomer achieves a high conductivity of 168.5 mS cm^(-1)at 80℃.At the same time,the water uptake is 40.0%and the swelling ratio is 12.1%.In addition,these membranes also have good mechanical properties and alkaline stability.After 1440 h of treatment in a NaOH(2 M)solution at 80℃,PPTP3F_(x)-DIL still maintains excellent tensile strength(>30.3 MPa)and elongation at break(>43.4%),and the conductivity retention of the PPTP3F_(1)-DIL membrane is 90.3%.The PPTP3F_(4)-DIL-based single cell exhibits a high peak power density(918.1 mW cm^(-2))and excellent durability(100 h)at 80℃.Therefore,these PPTP3F_(x)-DIL membranes have a wide range of applications in AEMFCs.展开更多
In rock mass and mining engineering,shock waves induced by engineering disturbances significantly affect rock mass stability.To explore the dynamic mechanical behavior and energy dissipation mechanisms of single-fract...In rock mass and mining engineering,shock waves induced by engineering disturbances significantly affect rock mass stability.To explore the dynamic mechanical behavior and energy dissipation mechanisms of single-fractured composite rock masses under impact loading,a series of tests were conducted using a split Hopkinson pressure bar(SHPB)system with a 50 mm rod diameter.Specimens containing a single inclined fracture with seven different dip angles and located in different lithological layers were tested.The results show that both peak stress and peak strain exhibit a non-monotonic trend with increasing dip angleα-first decreasing,then increasing,reaching a minimum atα=45°.This behavior is attributed to enhanced energy concentration and dissipation in the fracture zone,where shear-dominated failure leads to more effective crack propagation and stress redistribution.Moreover,the proportion of crushing energy dissipation is significantly affected by the fracture dip angle,reaching a minimum atα=45°and a maximum atα=90°,indicating a transition from shear to tensile failure modes with increasing angle.Lithology also plays a crucial role:grey sandstone specimens absorbed more energy compared to yellow sandstone,implying higher impact resistance due to differences in microstructural cohesion.The evolution of fragment fractal dimension with increasing dip angle follows an"M-shaped"trend,reflecting changes in fragmentation intensity and failure mode.Notably,yellow sandstone tends to produce higher fractal dimensions,with larger mass but smaller volume of powdered debris,indicating more intense fragmentation.This study reveals the coupling effect of fracture dip angle and lithology on dynamic mechanical response and energy evolution,providing new insights into the failure mechanisms of layered composite rock masses under impact loading.展开更多
Nicotine,ethanol,and caffeine are the most common exogenous substances in the men’s living environment,but their effects on the cartilage quality in the father and offspring have not been reported.According to the av...Nicotine,ethanol,and caffeine are the most common exogenous substances in the men’s living environment,but their effects on the cartilage quality in the father and offspring have not been reported.According to the average daily intake of adult men,we constructed a male rat model of paternal mixed exposure(PME)to low-dose nicotine(0.1 mg/(kg·day)),ethanol(0.5 g/(kg·day)),and caffeine(7.5 mg/(kg·day))for 8 weeks.Then,the male rats mated with normal female rats to obtain offspring.The results showed that PME reduced the cartilage quality of paternal and offspring rats.Among them,the paternal cartilage was damaged by enhancing matrix degradation,while the offspring cartilage was damaged by reducing matrix synthesis.The cartilage damage in male offspring rats was more evident than in female offspring.It was further confirmed that differential GC regulation mechanisms were the main reasons for the intergenerational differential damage of paternal/offspring cartilage quality caused by PME.In addition,the androgen receptor(AR)and estrogen receptor beta(ERβ)mediated the sex difference of PME-induced fetal cartilage dysplasia by affecting the binding degree of GR/P300.This study provided a theoretical and experimental basis for guiding male healthy lifestyle and exploring early prevention and treatment strategies for paternal diseases.展开更多
The main purpose of this research is to optimize the hydrothermal performance of a dimpled tube by augmenting the surface area for heat transmission and thermal layer cracking.To achieve that,the impact of different d...The main purpose of this research is to optimize the hydrothermal performance of a dimpled tube by augmenting the surface area for heat transmission and thermal layer cracking.To achieve that,the impact of different dimple diameters and their distribution along the dimpled tube was investigated numerically using the ANSYS Fluent 2022 R1 software by considering two models,A and B.Both models consist of three regions;the first,second,and third have dimple diameters of 3,2,&1 mm,respectively.Model A included an in-line dimple arrangement,while model B involved a staggered dimple arrangement.The finite volume method(FVM)was used in the modeling techniques to address the turbulent flow problem,which ranged in this investigation from Re of 3000 to 8000.The cooling fluid used in this investigation is water,which concentrated primarily on single-phase flow conditions.The investigation results revealed that as the Re increased,all analyzed models showcased higher.A reduction in pressure drops,thermal resistance,Nu,and overall performance standards.Crucially,compared to the traditionalmodel,both suggested models demonstrated improved heat transmission capacities.Within all the models examined,the tube with dimples in(model B)as staggered showed the greatest enhancement in the Nu,which was almost double that of the conventional type.Model A and Model B have respective average total performance criteria of 1.23 and 1.34.展开更多
The development of an analytical method for determining the properties of quantum dots(QDs)is crucial for improving the optical performance of QD-based displays.Therefore,synchrotron-based X-ray photoelectron spectros...The development of an analytical method for determining the properties of quantum dots(QDs)is crucial for improving the optical performance of QD-based displays.Therefore,synchrotron-based X-ray photoelectron spectroscopy(XPS)is designed here to accurately characterize the chemical and structural differences between different QDs.This method enables the determination of the reason for the minimal differences between the optical properties of different QDs depending on the synthesis process,which is difficult to determine using conventional methods alone.Combined with model simulations,the XPS spectra obtained at different photon energies reveal the internal structures and chemical-state distributions of the QDs.In particular,the QD synthesized under optimal conditions demonstrates a relatively lower degree of oxidation of the core and more uniformly stacked ZnSe/ZnS shell layers.The internal structures and chemical-state distributions of QDs are closely related to their optical properties.Finally,the synchrotron-based XPS proposed here can be applied to compare nearly equivalent QDs with slightly different optical properties.展开更多
As emerging services continue to be explored,indoor communications geared towards different user requirements will face severe challenges such as larger penetration losses and more critical multipath issues,leading to...As emerging services continue to be explored,indoor communications geared towards different user requirements will face severe challenges such as larger penetration losses and more critical multipath issues,leading to difficulties in achieving flexible coverage.In this paper,we introduce transmissive reconfigurable intelligent surfaces(RISs)as intelligent passive auxiliary devices into indoor scenes,replacing conventional ultra-dense small cell and relay forwarding approaches to address these issues at low deployment and operation costs.Specifically,we study the optimization design of active and passive beamforming for the transmissive RISs-aided indoor multiuser downlink communication systems.This involves considering more realistic indoor congestion modeling and near-field propagation characteristics.The goal of our optimization is to minimize the total transmit power at the access point(AP)for different user service requirements,including quality-of-service(QoS)and wireless power transfer(WPT).Due to the nonconvex nature of the optimization problem,adaptive penalty coefficients are imported to solve it alternatively with closed-form solutions for both active and passive beamforming.Simulation results demonstrate that the use of transmissive RISs is indeed an efficient way to achieve flexible coverage in indoor scenarios.Furthermore,the proposed optimization algorithm has been proven to be effective and robust in achieving energy-saving transmission.展开更多
In 2022,Leukemia is the 13th most common diagnosis of cancer globally as per the source of the International Agency for Research on Cancer(IARC).Leukemia is still a threat and challenge for all regions because of 46.6...In 2022,Leukemia is the 13th most common diagnosis of cancer globally as per the source of the International Agency for Research on Cancer(IARC).Leukemia is still a threat and challenge for all regions because of 46.6%infection in Asia,and 22.1%and 14.7%infection rates in Europe and North America,respectively.To study the dynamics of Leukemia,the population of cells has been divided into three subpopulations of cells susceptible cells,infected cells,and immune cells.To investigate the memory effects and uncertainty in disease progression,leukemia modeling is developed using stochastic fractional delay differential equations(SFDDEs).The feasible properties of positivity,boundedness,and equilibria(i.e.,Leukemia Free Equilibrium(LFE)and Leukemia Present Equilibrium(LPE))of the model were studied rigorously.The local and global stabilities and sensitivity of the parameters around the equilibria under the assumption of reproduction numbers were investigated.To support the theoretical analysis of the model,the Grunwald Letnikov Nonstandard Finite Difference(GL-NSFD)method was used to simulate the results of each subpopulation with memory effect.Also,the positivity and boundedness of the proposed method were studied.Our results show how different methods can help control the cell population and give useful advice to decision-makers on ways to lower leukemia rates in communities.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61101175,61571305,and 61227802)
文摘A fast and simple method to extract phase-contrast images from interferograms is proposed, and its effectiveness is demonstrated through simulation and experiment. For x-ray differential phase contrast imaging, a strong attenuation signal acts as an overwhelming background intensity that obscures the weak phase signal so that no obvious phase-gradient information is detectable in the raw image. By subtracting one interferogram from another, chosen at particular intervals,the phase signal can be isolated and magnified.
基金supported by the National Natural Science Foundation of China(Grant Nos.11275204,11475175,and 11405175)the China Postdoctoral Science Foundation(Grant No.2017M612097)the Fundamental Research Funds for the Central Universities(Grant No.WK2310000065)
文摘X-ray grating interferometer has attracted widely attention in the past years due to its capability in achieving x-ray phase contrast imaging with low brilliance source. However, the widely used phase stepping information extraction method reduces system stability and prolongs data acquisition time by several times compared with conventional x-ray absorption- based imaging. The mechanical stepping can be avoided by using a staggered grating, but at the cost of low vertical spatial resolution. In this paper, employing a modified staggered grating and the angular signal radiography, we proposed a single-shot grating-based x-ray differential phase contrast imaging with decent vertical spatial resolution. The theoretical framework was deduced and proved by numerical experiments. Absorption, phase, and scattering computed tomography can be performed without phase stepping. Therefore, we believe this fast and highly stable imaging method with decent resolution would be widely applied in x-ray grating-based phase contrast imaging.
文摘Objective Magnetoencephalography(MEG),a non-invasive neuroimaging technique,meticulously captures the magnetic fields emanating from brain electrical activity.Compared with MEG based on superconducting quantum interference devices(SQUID),MEG based on optically pump magnetometer(OPM)has the advantages of higher sensitivity,better spatial resolution and lower cost.However,most of the current studies are clinical studies,and there is a lack of animal studies on MEG based on OPM technology.Pain,a multifaceted sensory and emotional phenomenon,induces intricate alterations in brain activity,exhibiting notable sex differences.Despite clinical revelations of pain-related neuronal activity through MEG,specific properties remain elusive,and comprehensive laboratory studies on pain-associated brain activity alterations are lacking.The aim of this study was to investigate the effects of inflammatory pain(induced by Complete Freund’s Adjuvant(CFA))on brain activity in a rat model using the MEG technique,to analysis changes in brain activity during pain perception,and to explore sex differences in pain-related MEG signaling.Methods This study utilized adult male and female Sprague-Dawley rats.Inflammatory pain was induced via intraplantar injection of CFA(100μl,50%in saline)in the left hind paw,with control groups receiving saline.Pain behavior was assessed using von Frey filaments at baseline and 1 h post-injection.For MEG recording,anesthetized rats had an OPM positioned on their head within a magnetic shield,undergoing two 15-minute sessions:a 5-minute baseline followed by a 10-minute mechanical stimulation phase.Data analysis included artifact removal and time-frequency analysis of spontaneous brain activity using accumulated spectrograms,generating spectrograms focused on the 4-30 Hz frequency range.Results MEG recordings in anesthetized rats during resting states and hind paw mechanical stimulation were compared,before and after saline/CFA injections.Mechanical stimulation elevated alpha activity in both male and female rats pre-and post-saline/CFA injections.Saline/CFA injections augmented average power in both sexes compared to pre-injection states.Remarkably,female rats exhibited higher average spectral power 1 h after CFA injection than after saline injection during resting states.Furthermore,despite comparable pain thresholds measured by classical pain behavioral tests post-CFA treatment,female rats displayed higher average power than males in the resting state after CFA injection.Conclusion These results imply an enhanced perception of inflammatory pain in female rats compared to their male counterparts.Our study exhibits sex differences in alpha activities following CFA injection,highlighting heightened brain alpha activity in female rats during acute inflammatory pain in the resting state.Our study provides a method for OPM-based MEG recordings to be used to study brain activity in anaesthetized animals.In addition,the findings of this study contribute to a deeper understanding of pain-related neural activity and pain sex differences.
基金supported by grants from the National Key Research and Development Program(2022YFA1104401)CAMS Innovation Fund for Medical Sciences(2019-I2M-5-031 to Z.P.F.)grants from Innovation Research Team Project of Beijing Stomatological Hospital,Capital Medical University(NO.CXTD202204 to Z.P.F.).
文摘Dental mesenchymal stem cells(DMSCs)are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differentiation potential and self-renewal ability.The cellular microenvironment regulates the fate of stem cells and can be modified using various optimization techniques.These methods can influence the cellular microenvironment,activate disparate signaling pathways,and induce different biological effects.“Epigenetic regulation”refers to the process of influencing gene expression and regulating cell fate without altering DNA sequences,such as histone methylation.Histone methylation modifications regulate pivotal transcription factors governing DMSCs differentiation into osteo-/odontogenic lineages.The most important sites of histone methylation in tooth organization were found to be H3K4,H3K9,and H3K27.Histone methylation affects gene expression and regulates stem cell differentiation by maintaining a delicate balance between major trimethylation sites,generating distinct chromatin structures associated with specific downstream transcriptional states.Several crucial signaling pathways associated with osteogenic differentiation are susceptible to modulation via histone methylation modifications.A deeper understanding of the regulatory mechanisms governing histone methylation modifications in osteo-/odontogenic differentiation and immune-inflammatory responses of DMSCs will facilitate further investigation of the epigenetic regulation of histone methylation in DMSC-mediated tissue regeneration and inflammation.Here is a concise overview of the pivotal functions of epigenetic histone methylation at H3K4,H3K9,and H3K27 in the regulation of osteo-/odontogenic differentiation and renewal of DMSCs in both non-inflammatory and inflammatory microenvironments.This review summarizes the current research on these processes in the context of tissue regeneration and therapeutic interventions.
基金supported by the Natural Science Foundation of Hunan Province,China(Grant Nos.2023JJ50178 and 2023JJ50194)the Excellent Youth Project of Hunan Provincial Department of Education(Grant No.23B0542).
文摘Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this system,its economic feasibility,water usage effectiveness(WUE),and carbon usage effectiveness(CUE)remain underexplored.This study introduces a comprehensive evaluation index designed to assess the applicability of the rack-level loop thermosyphon system across various computing hub nodes.The air wet bulb temperature Ta,w was identified as the most significant factor influencing the variability in the combination of PUE,CUE,and WUE values.The results indicate that the rack-level loop thermosyphon system achieves the highest score in Lanzhou(94.485)and the lowest in Beijing(89.261)based on the comprehensive evaluation index.The overall ranking of cities according to the comprehensive evaluation score is as follows:Gansu hub(Lanzhou)>Inner Mongolia hub(Hohhot)>Ningxia hub(Yinchuan)>Yangtze River Delta hub(Shanghai)>Chengdu Chongqing hub(Chongqing)>Guangdong-Hong Kong-Macao Greater Bay Area hub(Guangzhou)>Guizhou hub(Guiyang)>Beijing-Tianjin-Hebei hub(Beijing).Furthermore,Hohhot,Lanzhou,and Yinchuan consistently rank among the top three cities for comprehensive scores across all load rates,while Guiyang(at a 25%load rate),Guangzhou(at a 50%load rate),and Beijing(at 75%and 100%load rates)exhibited the lowest comprehensive scores.
基金Science and Technology Research Project of Guang-dong Meteorological Bureau(GRMC2022M21)Guangdong Basic and Applied Basic Research Foundation(2023A1515012240)Research Project of Guangzhou Meteor-ological Bureau(M202218)。
文摘Reasonable greening design can effectively alleviate campus heat environment issues.This study uses the ENVI-met numerical model,along with in-situ observations and simulations,to analyze the thermal environment under three different greening schemes in typical areas of the Guangzhou University campus.The results indicate that the outdoor thermal environment is significantly influenced by the underlying surface materials and vegetation.The temperature of brick-paved surface is 0.9℃higher than that of natural soil surfaces under tree shade.Numerical simulations further confirm that increasing vegetation coverage effectively reduces outdoor air temperature.When the greening rate increases to 40%,the outdoor average temperature decreases by 0.7℃and relative humidity increases by approximately 4%,while wind speed remains minimal change.The cooling effect of vegetation is found to extend vertically to an altitude of 13 m.As the greening rate increases from 15%to 40%,the Mean Radiant Temperature(MRT)decreases from 50.6℃to 28.9℃,which is lower than the average ambient temperature,indicating improved thermal conditions.The Physiological Equivalent Temperature(PET)decreases from 40.2℃to 30.0℃,with the proportion of the areas classified as″very hot″reducing by 36.8%,significantly improving thermal comfort across most areas.Therefore,changing the ground material and greening landscape design can effectively alter the outdoor wind and thermal environment of the campus,thereby enhancing the thermal comfort for the campus community.
基金supported by the National Natural Science Foundation of China(Grant no.32101237)the China Postdoctoral Science Foundation(Grant no.2021M691522)+1 种基金the National Key Research and Development Program(Grant no.2022YFC3202104)the Tibet Major Science and Technology Project(Grant no.XZ201901-GA-06).
文摘Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studies on collective behavior in small animals such as fish and insects are well-established,similar research on large wild animals remains challenging due to the limited availability of sufficient and systematic field data.Here,we aimed to explore the collective decision-making pattern and its sexual difference for the dimorphic Tibetan antelopes Pantholops hodgsonii(chiru)in Xizang Autonomous Region,China,by analyzing individual leadership distribution,as well as the joining process,considering factors such as calving stages and joining ranks.The distinct correlations of decision participants’ratio with group size and decision duration underscore the trade-off between accuracy and speed in decision-making.Male antelopes display a more democratic decision-making pattern,while females exhibit more prompt responses after calving at an early stage.This study uncovers a partially shared decision-making strategy among Tibetan antelopes,suggesting flexible self-organization in group decision processes aligned with animal life cycle progression.
文摘The release of essential nutrients from soil minerals for plant growth in calcareous soils,facilitated by organic extractants,is critical in semi-arid areas,particularly for elements affected by high soil pH.This study aims to investigate the release of calcium(Ca),magnesium(Mg),and phosphorus(P)through the application of wood vinegar extract in surface calcareous soils in Borojerd City,Lorestan Province,Iran.The experiment was conducted using a completely randomized design with three replications.The treatments included soils from three different land uses:vineyard,wheat field,and rangeland,each treated with 1.00%wood vinegar solution.Cumulative measurements of the specified elements were recorded over 10 consecutive 0.5 h intervals.The release data were analyzed using four various kinetic models(Elovich equation,parabolic diffusion law,power function equation,and zero-order kinetics).The highest concentrations recorded were for Ca(39,500.00 mg/kg),Mg(5880.00 mg/kg),and P(5.00 mg/kg)in grape cultivation.The findings revealed a significant difference in Ca release between grape cultivation and rangeland(P<0.01),while the Mg release showed a significant difference between both grape cultivation and rangeland and wheat cultivation(P<0.01).Additionally,the cumulative release of P showed significant differences between grape cultivation and both wheat and rangeland(P<0.01).The results indicated that the zero-order kinetics provided the best fit for the data(R^(2)=0.99).The maximum initial release amount was observed in grape cultivation when applying the zero-order kinetics,while the highest release rate was achieved using the parabolic diffusion law across three applications.Wood vinegar had the capacity to degrade various clay minerals,including vermiculite,smectite,palygorskite,and,to some extent,illite,resulting in the release of associated elements.Consequently,it can be concluded that wood vinegar can be effectively utilized in grape cultivation as an agent for reducing soil acidity,thereby enhancing the availability of soil nutrients and decreasing reliance on chemical fertilizers.
基金Supported by the National Natural Science Foundation of China(11871260,11761050)the Jiangxi Natural Science Foundation(#20232ACB201005)+1 种基金the Shandong Natural Science Foundation(#ZR2024MA024)Doctoral Startup Fund of Jiangxi Science and Technology Normal University(#2021BSQD30).
文摘The main purpose of this paper is to try to find all entire solutions of the Fermat type difference-differential equation[p1(z)f(z+c)]^(2)+[p2(z)f(z)+p3(z)f′(z)]^(2)=p(z);or[p1(z)f(z)]^(2)+[p2(z)f′(z)+p3(z)f(z+c)]^(2)=p(z)or[p1(z)f′(z)]^(2)+[p2(z)f(z+c)+p3(z)f(z)]^(2)=p(z);where c is a nonzero complex number,p1;p2 and p3 are polynomials in C satisfying p1p3■0;and p is a nonzero irreducible polynomial in C.
基金Educational and Teaching Reform Project of Beihua University:Research on the Construction of“Same Course with Different Structures”Course Resources Based on Knowledge Graphs。
文摘This paper explores the construction methods of“Same Course with Different Structures”curriculum resources based on knowledge graphs and their applications in the field of education.By reviewing the theoretical foundations of knowledge graph technology,the“Same Course with Different Structures”teaching model,and curriculum resource construction,and integrating existing literature,the paper analyzes the methods for constructing curriculum resources using knowledge graphs.The research finds that knowledge graphs can effectively integrate multi-source data,support personalized teaching and precision education,and provide both a scientific foundation and technical support for the development of curriculum resources within the“Same Course with Different Structures”framework.
文摘In order to solve the problem of the variable coefficient ordinary differen-tial equation on the bounded domain,the Lagrange interpolation method is used to approximate the exact solution of the equation,and the error between the numerical solution and the exact solution is obtained,and then compared with the error formed by the difference method,it is concluded that the Lagrange interpolation method is more effective in solving the variable coefficient ordinary differential equation.
基金funded by the National Natural Science Foundation of China(12363009 and 12103020)Natural Science Foundation of Jiangxi Province(20224BAB211011)+1 种基金Youth Talent Project of Science and Technology Plan of Ganzhou(2022CXRC9191 and 2023CYZ26970)Jiangxi Province Graduate Innovation Special Funds Project(YC2024-S529 and YC2023-S672).
文摘Planetary surfaces,shaped by billions of years of geologic evolution,display numerous impact craters whose distribution of size,density,and spatial arrangement reveals the celestial body's history.Identifying these craters is essential for planetary science and is currently mainly achieved with deep learning-driven detection algorithms.However,because impact crater characteristics are substantially affected by the geologic environment,surface materials,and atmospheric conditions,the performance of deep learning models can be inconsistent between celestial bodies.In this paper,we first examine how the surface characteristics of the Moon,Mars,and Earth,along with the differences in their impact crater features,affect model performance.Then,we compare crater detection across celestial bodies by analyzing enhanced convolutional neural networks and U-shaped Convolutional Neural Network-based models to highlight how geology,data,and model design affect accuracy and generalization.Finally,we address current deep learning challenges,suggest directions for model improvement,such as multimodal data fusion and cross-planet learning and list available impact crater databases.This review can provide necessary technical support for deep space exploration and planetary science,as well as new ideas and directions for future research on automatic detection of impact craters on celestial body surfaces and on planetary geology.
基金Under the auspices of the National Natural Science Foundation of China(No.32371863)Fundamental Research Funds for the Central Universities(No.2572025AW39)。
文摘Understanding the complex relationship between vegetation change and both natural and anthropogenic factors is a subject of global importance.However,comprehensive explanations of vegetation cover trends across China’s different regions and the dynamic roles of their drivers remain limited.This study analyzed national and regional vegetation change trends from 2000 to 2020 and evaluated the evolving impacts of natural and anthropogenic factors.Results indicate that 44.14%of China’s land experienced significant increase(P<0.05)in vegetation coverage.The Northeast(A1),Southwest(A5),and South China(A8)regions showed extremely significant increases in vegetation cover,with over 65%of vegetation exhibiting extremely significant growth(P<0.01).In contrast,less than 25%of vegetation in Inner Mongolia(A2),Northwest(A3),and the Qinghai-Tibetan Plateau(A4)subregions demonstrated an extremely significant increasing trend(P<0.01).Precipitation(q=0.766)and land use type(q=0.636)were the most influential natural and anthropogenic factors,respectively,with their interaction(q=0.838)dominating national vegetation patterns.On the west side of the Hu Line,vegetation dynamics were mainly limited by arid and semi-arid climates,with precipitation as the dominant factor,though land use measures have contributed to some vegetation improvement.Between 2000 and 2020,the influence of precipitation on vegetation cover increased in regions A3 and A4,with q-values rising by 26.73%and 101.13%,respectively.Additionally,soil type exerted a significant effect(P<0.001)on vegetation cover across all regions,being most pronounced in A2(q=0.692).On the east side of the Hu Line,vegetation growth benefited generally from warm and humid conditions,while local decline in urbanized areas was largely attributable to land use change and economic expansion.Concurrently anthropogenic factors such as land use and population density increasingly influenced vegetation dynamics in eastern urban areas of the Hu Line.Population density and GDP were the most influential factors affecting vegetation cover in region A8,with q-values of 0.443 and 0.380,respectively(P<0.001).Future efforts should maintain the benefits of large-scale ecological projects and harmonize the relationship between urban vegetation and anthropogenic influences.
基金support of the National Natural Science Foundation of China(Grant 22278340&22078272)。
文摘Improving the comprehensive performance of anion exchange membranes(AEMs)has a decisive impact on the wide application of anion exchange membrane fuel cells(AEMFCs).Herein,we prepared a series of new poly(phenanthrene-co-p-terphenyl piperidinium)(PPTP3F_(x)-DIL)AEMs with different fluorinated monomers for high performance AEMFCs.The polymerization of fluorinated monomers with other aryl monomers can effectively promote the separation of microphase in the membrane.It also has a high OH-conductivity at a low swelling.The membrane(PPTP3F_(4)-DIL)prepared by polycondensation of 2,2,2-trifluoro-1-(p-tolyl)ethan 1-one monomer achieves a high conductivity of 168.5 mS cm^(-1)at 80℃.At the same time,the water uptake is 40.0%and the swelling ratio is 12.1%.In addition,these membranes also have good mechanical properties and alkaline stability.After 1440 h of treatment in a NaOH(2 M)solution at 80℃,PPTP3F_(x)-DIL still maintains excellent tensile strength(>30.3 MPa)and elongation at break(>43.4%),and the conductivity retention of the PPTP3F_(1)-DIL membrane is 90.3%.The PPTP3F_(4)-DIL-based single cell exhibits a high peak power density(918.1 mW cm^(-2))and excellent durability(100 h)at 80℃.Therefore,these PPTP3F_(x)-DIL membranes have a wide range of applications in AEMFCs.
基金financially supported by the National Natural Science Foundation of China(No.52204137)the Outstanding Young Scientific and Technological Talents Project of Liaoning University of Science and Technology(NO.2023YQ10)+3 种基金the Education Department Foundation of Liaoning Province(NO.LJKQZ20222317)the Natural Science Foundation of Shandong Province(Grant No.ZR2020QE121,ZR202211080074)the upport Program for Youth Innovation and Entrepreneurship in Higher Education Institutions of Shandong Province(Grant No.2022KJ101)the Support Program for Youth Innovation and Entrepreneurship in Higher Education Institutions of Shandong Province(Grant No.2022KJ101)。
文摘In rock mass and mining engineering,shock waves induced by engineering disturbances significantly affect rock mass stability.To explore the dynamic mechanical behavior and energy dissipation mechanisms of single-fractured composite rock masses under impact loading,a series of tests were conducted using a split Hopkinson pressure bar(SHPB)system with a 50 mm rod diameter.Specimens containing a single inclined fracture with seven different dip angles and located in different lithological layers were tested.The results show that both peak stress and peak strain exhibit a non-monotonic trend with increasing dip angleα-first decreasing,then increasing,reaching a minimum atα=45°.This behavior is attributed to enhanced energy concentration and dissipation in the fracture zone,where shear-dominated failure leads to more effective crack propagation and stress redistribution.Moreover,the proportion of crushing energy dissipation is significantly affected by the fracture dip angle,reaching a minimum atα=45°and a maximum atα=90°,indicating a transition from shear to tensile failure modes with increasing angle.Lithology also plays a crucial role:grey sandstone specimens absorbed more energy compared to yellow sandstone,implying higher impact resistance due to differences in microstructural cohesion.The evolution of fragment fractal dimension with increasing dip angle follows an"M-shaped"trend,reflecting changes in fragmentation intensity and failure mode.Notably,yellow sandstone tends to produce higher fractal dimensions,with larger mass but smaller volume of powdered debris,indicating more intense fragmentation.This study reveals the coupling effect of fracture dip angle and lithology on dynamic mechanical response and energy evolution,providing new insights into the failure mechanisms of layered composite rock masses under impact loading.
基金supported by the National Natural Science Foundation of China(U22A20362,U23A20407,82030111,82104301)Hubei Province’s Outstanding Medical Academic Leader program.
文摘Nicotine,ethanol,and caffeine are the most common exogenous substances in the men’s living environment,but their effects on the cartilage quality in the father and offspring have not been reported.According to the average daily intake of adult men,we constructed a male rat model of paternal mixed exposure(PME)to low-dose nicotine(0.1 mg/(kg·day)),ethanol(0.5 g/(kg·day)),and caffeine(7.5 mg/(kg·day))for 8 weeks.Then,the male rats mated with normal female rats to obtain offspring.The results showed that PME reduced the cartilage quality of paternal and offspring rats.Among them,the paternal cartilage was damaged by enhancing matrix degradation,while the offspring cartilage was damaged by reducing matrix synthesis.The cartilage damage in male offspring rats was more evident than in female offspring.It was further confirmed that differential GC regulation mechanisms were the main reasons for the intergenerational differential damage of paternal/offspring cartilage quality caused by PME.In addition,the androgen receptor(AR)and estrogen receptor beta(ERβ)mediated the sex difference of PME-induced fetal cartilage dysplasia by affecting the binding degree of GR/P300.This study provided a theoretical and experimental basis for guiding male healthy lifestyle and exploring early prevention and treatment strategies for paternal diseases.
文摘The main purpose of this research is to optimize the hydrothermal performance of a dimpled tube by augmenting the surface area for heat transmission and thermal layer cracking.To achieve that,the impact of different dimple diameters and their distribution along the dimpled tube was investigated numerically using the ANSYS Fluent 2022 R1 software by considering two models,A and B.Both models consist of three regions;the first,second,and third have dimple diameters of 3,2,&1 mm,respectively.Model A included an in-line dimple arrangement,while model B involved a staggered dimple arrangement.The finite volume method(FVM)was used in the modeling techniques to address the turbulent flow problem,which ranged in this investigation from Re of 3000 to 8000.The cooling fluid used in this investigation is water,which concentrated primarily on single-phase flow conditions.The investigation results revealed that as the Re increased,all analyzed models showcased higher.A reduction in pressure drops,thermal resistance,Nu,and overall performance standards.Crucially,compared to the traditionalmodel,both suggested models demonstrated improved heat transmission capacities.Within all the models examined,the tube with dimples in(model B)as staggered showed the greatest enhancement in the Nu,which was almost double that of the conventional type.Model A and Model B have respective average total performance criteria of 1.23 and 1.34.
基金Advanced Light Source,which is a DOE Office of Science User Facility under contract no.DE-AC02-05CH11231the Basque Government for funding through a PhD Fellowship(Grant no.PRE_2018_2_0285)+1 种基金through Egonlabur Travel Fellowship(Grant no.EP_2018_1_0004)partially supported by an Early Career Award in the Condensed Phase and Interfacial Molecular Science Program,in the Chemical Sciences Geosciences and Biosciences Division of the Office of Basic Energy Sciences of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231.
文摘The development of an analytical method for determining the properties of quantum dots(QDs)is crucial for improving the optical performance of QD-based displays.Therefore,synchrotron-based X-ray photoelectron spectroscopy(XPS)is designed here to accurately characterize the chemical and structural differences between different QDs.This method enables the determination of the reason for the minimal differences between the optical properties of different QDs depending on the synthesis process,which is difficult to determine using conventional methods alone.Combined with model simulations,the XPS spectra obtained at different photon energies reveal the internal structures and chemical-state distributions of the QDs.In particular,the QD synthesized under optimal conditions demonstrates a relatively lower degree of oxidation of the core and more uniformly stacked ZnSe/ZnS shell layers.The internal structures and chemical-state distributions of QDs are closely related to their optical properties.Finally,the synchrotron-based XPS proposed here can be applied to compare nearly equivalent QDs with slightly different optical properties.
基金supported in part by the Natural Science Basic Research Plan in Shaanxi Province under Grant 2024JC-ZDXM-36in part by the Key Research and Development Program of Shaanxi Province under Grant 2023-YBGY-255+2 种基金in part by the Excellent Youth Science Foundation of Xi’an University of Science and Technology under Grant 2019YQ3-13in part by the Xi’an Key Laboratory of Network Convergence Communications under Grant 2022NCC-K102in part by the Fundamental Research Funds for the Central Universities under Grant QTZX23029。
文摘As emerging services continue to be explored,indoor communications geared towards different user requirements will face severe challenges such as larger penetration losses and more critical multipath issues,leading to difficulties in achieving flexible coverage.In this paper,we introduce transmissive reconfigurable intelligent surfaces(RISs)as intelligent passive auxiliary devices into indoor scenes,replacing conventional ultra-dense small cell and relay forwarding approaches to address these issues at low deployment and operation costs.Specifically,we study the optimization design of active and passive beamforming for the transmissive RISs-aided indoor multiuser downlink communication systems.This involves considering more realistic indoor congestion modeling and near-field propagation characteristics.The goal of our optimization is to minimize the total transmit power at the access point(AP)for different user service requirements,including quality-of-service(QoS)and wireless power transfer(WPT).Due to the nonconvex nature of the optimization problem,adaptive penalty coefficients are imported to solve it alternatively with closed-form solutions for both active and passive beamforming.Simulation results demonstrate that the use of transmissive RISs is indeed an efficient way to achieve flexible coverage in indoor scenarios.Furthermore,the proposed optimization algorithm has been proven to be effective and robust in achieving energy-saving transmission.
基金supported by the Fundacao para a Ciencia e Tecnologia,FCT,under the project https://doi.org/10.54499/UIDB/04674/2020(accessed on 1 January 2025).
文摘In 2022,Leukemia is the 13th most common diagnosis of cancer globally as per the source of the International Agency for Research on Cancer(IARC).Leukemia is still a threat and challenge for all regions because of 46.6%infection in Asia,and 22.1%and 14.7%infection rates in Europe and North America,respectively.To study the dynamics of Leukemia,the population of cells has been divided into three subpopulations of cells susceptible cells,infected cells,and immune cells.To investigate the memory effects and uncertainty in disease progression,leukemia modeling is developed using stochastic fractional delay differential equations(SFDDEs).The feasible properties of positivity,boundedness,and equilibria(i.e.,Leukemia Free Equilibrium(LFE)and Leukemia Present Equilibrium(LPE))of the model were studied rigorously.The local and global stabilities and sensitivity of the parameters around the equilibria under the assumption of reproduction numbers were investigated.To support the theoretical analysis of the model,the Grunwald Letnikov Nonstandard Finite Difference(GL-NSFD)method was used to simulate the results of each subpopulation with memory effect.Also,the positivity and boundedness of the proposed method were studied.Our results show how different methods can help control the cell population and give useful advice to decision-makers on ways to lower leukemia rates in communities.
