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Multi-stream signals separation based on space-time-isomeric (SPATIO) array using metasurface antennas

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Science China(Information Sciences) 2024年第2期67卷 181-200页

作者： Yangming LOU Liang JIN Huiming wang zhou ZHONG Junyan dai PLA Strategic Support Force Information Engineering University School of Information and Communications Engineering Xi'an Jiaotong University 3. State Key Laboratory of Millimeter WavesSoutheast University

In spatial domain signal processing, it is necessary to equip more antennas at the receiver to improve spatial demultiplexing capability. However, increasing the number of antennas under restricted space will reduce antenna spacing and raise the channel correlation, making the number of signal streams spatially demultiplexed much smaller than that of antennas. This paper proposes a method to design a space-timeisomeric(SPATIO) array based on metasurface antennas under wireless multipath conditions. Each antenna in this array has a different pattern and varies independently with time, reducing the channel correlation by superposing multipath at distinct positions and moments. Based on the SPATIO array, we present an array parameter design scheme based on infinity norm minimization, which can maximize the received energy of each stream while separating multi-stream received signals. Simulation results illustrate the performance of the SPATIO array for multi-stream signal reception. Compared with conventional multiple-input multipleoutput arrays, the proposed array can reduce the bit error rate by one order of magnitude under the same simulation conditions.

关键词： multiple-input multiple-output metasurface antenna space-time-isomeric array multipath channel degree of freedom

A hybrid physics-informed data-driven neural network for CO_(2) storage in depleted shale reservoirs

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Petroleum Science 2024年第1期21卷 286-301页

作者： Yan-Wei wang Zhen-Xue dai Gui-Sheng wang Li Chen Yu-zhou Xia Yu-Hao zhou College of Construction Engineering Jilin UniversityChangchun130026JilinChina Institute of Intelligent Simulation and Early Warning for Subsurface Environment Jilin UniversityChangchun130026JilinChina School of Energy Resources China University of GeosciencesBeijing100083China Department of Safety Environmental Protection and Quality ManagementShengli OilfieldSinopecDongying257000ShandongChina Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an710049ShaanxiChina College of Computer Science and Technology China University of Petroleum(East China)Qingdao266580ShandongChina Department of Physics University of FribourgFribourg1700Switzerland

To reduce CO_(2) emissions in response to global climate change,shale reservoirs could be ideal candidates for long-term carbon geo-sequestration involving multi-scale transport processes.However,most current CO_(2) sequestration models do not adequately consider multiple transport mechanisms.Moreover,the evaluation of CO_(2) storage processes usually involves laborious and time-consuming numerical simulations unsuitable for practical prediction and decision-making.In this paper,an integrated model involving gas diffusion,adsorption,dissolution,slip flow,and Darcy flow is proposed to accurately characterize CO_(2) storage in depleted shale reservoirs,supporting the establishment of a training database.On this basis,a hybrid physics-informed data-driven neural network(HPDNN)is developed as a deep learning surrogate for prediction and inversion.By incorporating multiple sources of scientific knowledge,the HPDNN can be configured with limited simulation resources,significantly accelerating the forward and inversion processes.Furthermore,the HPDNN can more intelligently predict injection performance,precisely perform reservoir parameter inversion,and reasonably evaluate the CO_(2) storage capacity under complicated scenarios.The validation and test results demonstrate that the HPDNN can ensure high accuracy and strong robustness across an extensive applicability range when dealing with field data with multiple noise sources.This study has tremendous potential to replace traditional modeling tools for predicting and making decisions about CO_(2) storage projects in depleted shale reservoirs.

关键词： Deep learning Physics-informed data-driven neural network Depleted shale reservoirs CO_(2)storage Transport mechanisms

Effect of Er_(30)Cu_(70) on microstructure and properties of sintered Nd-Fe-B by grain boundary reconstruction

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Journal of Rare Earths 2024年第2期42卷 345-353,I0004页

作者： Kai wang Yongtao dai Jianqiu Deng Jiang wang Huaiying zhou Qingrong Yao Weichao Huang Guangxi Key Laboratory of Information Materials Schoolof Materials Science and EngineeringGuilin University of Electronic TechnologyGuilin54004China China Rare Metals and Rare Earth(Guangxi)Jinyuan New Materials Co Ltd.Hezhou542603China

Usually it is generally believed that the Er element forms the Er_(2)Fe_(14)B phase,which will seriously deteriorate the magnetic properties.Distinctly,here we report the balance of corrosion resistance and coercivity in Nd-Fe-B sintered magnets through using simple Er_(30)Cu_(70) additive whose price is much lower than Dy and Tb.By reasonably controlling Er_(30)Cu_(70) addition,the corrosion resistance is improved at the minimum limit of reducing the magnetic properties.Through studying the influence mechanism of Er element,it is found that the main effect of Er elements is to replace the Nd elements at the edge of the main phase grains to form a(Er,Nd)_(2)Fe_(14)B shell with low H_(A),resulting in the reduction of magnetic properties.The improvement of corrosion resistance mainly comes from the more stable Cu element introduced at the grain boundary.At the same time,the target magnets also show different advantages under different heat treatment methods.Above findings may spur progress towards developing the lowcost permanent magnets that rival the commercial Nd-Fe-B counterpart.

关键词： Er_(30)Cu_(70)alloy Grain boundary reconstruction Magnetic properties Corrosion resistance Heat treatment Rare earths

Automatic diagnosis of diabetic retinopathy using vision transformer based on wide-field optical coherence tomography angiography

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Journal of Innovative Optical Health Sciences 2024年第2期17卷 35-44页

作者： Zenan zhou Huanhuan Yu Jiaqing Zhao Xiangning wang Qiang Wu Cuixia dai Shanghai Institute of Technology Shanghai P.R.China Shanghai Sixth People'sHospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai P.R.China

Diabetic retinopathy(DR)is one of the major causes of visual impairment in adults with diabetes.Optical coherence tomography angiography(OCTA)is nowadays widely used as the golden criterion for diagnosing DR.Recently,wide-field OCTA(WF-OCTA)provided more abundant information including that of the peripheral retinal degenerative changes and it can contribute in accurately diagnosing DR.The need for an automatic DR diagnostic system based on WF-OCTA pictures attracts more and more attention due to the large diabetic population and the prevalence of retinopathy cases.In this study,automatic diagnosis of DR using vision transformer was performed using WF-OCTA images(12 mm×12 mm single-scan)centered on the fovea as the dataset.WF-OCTA images were automatically classified into four classes:No DR,mild nonproliferative diabetic retinopathy(NPDR),moderate to severe NPDR,and proliferative diabetic retinopathy(PDR).The proposed method for detecting DR on the test set achieves accuracy of 99.55%,sensitivity of 99.49%,and specificity of 99.57%.The accuracy of the method for DR staging reaches up to 99.20%,which has been proven to be higher than that attained by classical convolutional neural network models.Results show that the automatic diagnosis of DR based on vision transformer and WF-OCTA pictures is more effective for detecting and staging DR.

关键词： Wide field optical coherence tomography angiography diabetic retinopathy vision transformer image classification

Effects of coal-fired power plants on soil microbial diversity and community structures

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Journal of Environmental Sciences 2024年第3期137卷 206-223页

作者： Bowen Sun Renbin Zhu Yu Shi Wanying Zhang Zeming zhou Dawei Ma Runfang wang Haitao dai Chenshuai Che Institute of Polar Environment&Anhui Key Laboratory of Polar Environment and Global Change School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 450046China State Grid Anhui Electric Power Research Institute Hefei 230601China

Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power plants.However,the effects of coal-fired power plants on soil microbial communities have received little attention through atmospheric pollutant deposition and coal-stacking.Here,we collected the samples of power plant soils(PS),coal-stacking soils(CSS)and agricultural soils(AS)around three coal-fired power plants and background control soils(BG)in Huainan,a typical mineral resource-based city in East China,and investigated the microbial diversity and community structures through a high-throughput sequencing technique.Coal-stacking significantly increased(p<0.05)the contents of total carbon,total nitrogen,total sulfur and Mo in the soils,whereas the deposition of atmospheric pollutants enhanced the levels of V,Cu,Zn and Pb.Proteobacteria,Actinobacteria,Thaumarchaeota,Thermoplasmata,Ascomycota and Basidiomycota were the dominant taxa in all soils.The bacterial community showed significant differences(p<0.05)among PS,CSS,AS and BG,whereas archaeal and fungal communities showed significant differences(p<0.01)according to soil samples around three coal-fired power plants.The predominant environmental variables affecting soil bacterial,archaeal and fungal communities were Mo-TN-TS,Cu-V-Mo,and organic matter(OM)-Mo,respectively.Certain soil microbial genera were closely related to multiple key factors associated with stacking coal and heavy metal deposition from power plants.This study provided useful insight into better understanding of the relationships between soil microbial communities and long-term disturbances from coal-fired power plants.

关键词： Coal-fired power plants Soil microbial communities Coal-stacking Heavy metals Environmental variables

Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement

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Journal of Forestry Research 2024年第2期35卷 146-162页

作者： Yuanyuan wang Xinzhu dai Xingling Chen Dan Zhang Guiqing Lin Yuanhang zhou Tianyi wang Yulong Cui Academy of Forestry Sciences of Changchun Bureau of Forestry and Landscaping of ChangchunChangchun 130117People’s Republic of China College of Landscape Architecture Changchun UniversityChangchun 130022People’s Republic of China Changchun South Lake Park Bureau of Forestry and Landscaping of ChangchunChangchun 130012People’s Republic of China

Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future.

关键词： Species diversity Forest characteristics Biomass carbon sink Forest-type effect Urbanization effect Urban forests

Cav3.2 channel regulates cerebral ischemia/reperfusion injury:a promising target for intervention

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Neural Regeneration Research 2024年第11期19卷 2480-2487页

作者： Feibiao dai Chengyun Hu Xue Li Zhetao Zhang Hongtao wang Wanjun zhou Jiawu wang Qingtian Geng Yongfei Dong Chaoliang Tang Graduate School Wannan Medical CollegeWuhuAnhui ProvinceChina Department of Anesthesiology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Core Facility Center for Medical Sciences The First Affiliated Hospital of USTC(Anhui Provincial Hospital)HefeiAnhui ProvinceChina Department of Pharmacy The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Neurosurgery The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina

Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury.Various calcium channels are involved in cerebral ischemia/reperfusion injury.Cav3.2 channel is a main subtype of T-type calcium channels.T-type calcium channel blockers,such as pimozide and mibefradil,have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury.However,the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear.Here,in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons.The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons.We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury.Cav3.2 knockout markedly reduced infarct volume and brain water content,and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury.Additionally,Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress,inflammatory response,and neuronal apoptosis.In the hippocampus of Cav3.2-knockout mice,calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury.These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling.Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.

关键词： calcineurin Cav3.2 channel cerebral ischemia/reperfusion hippocampus hypoxia/reoxygenation inflammatory response nuclear factor of activated T cells 3 oxidative stress primary hippocampal neurons stroke

Current status and challenges in the application of microbial PHA particles

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Particuology 2024年第4期87卷 286-302页

作者： Jiaxuan Liu Ziqi zhou Haoru Li Xinyu Yang Zeyu wang jian Xiao dai-Xu Wei Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationSchool of MedicineDepartment of Life Sciences and MedicineNorthwest UniversityXi'an710069China School of Clinical Medicine Qujing Medical CollegeQujing655000China School of Physics and Electronic Information Shangrao Normal UniversityShangrao334001China Zigong Affiliated Hospital of Southwest Medical University Zigong Psychiatric Research CenterZigong Institute of Brain ScienceZigong643002China

Polyhydroxyalkanoates(PHAs)are diversiform biopolyesters with a similar structure and different side chain groups,synthesized by a variety of microorganism.Due to their excellent biodegradability and biocompatibility,PHAs have been used for many applications,including medical implants,antibacterial agents and bioengineering.Nano-architecture is an emerging area for the use of PHAs.This review summarizes the current status and challenges of PHAs-based particles on the micro-and nano-scale,including their production,degradation,biological safety,and surface functionalization.We also focus on the applications of PHA particles in drug delivery systems,environment protection,tissue engi-neering,vaccine engineering,food science,biotechnology and cosmetics.Finally,the future development trends of PHAs-based particles are prospected.

关键词： Polyhydroxyalkanoates(PHAs) Particles Synthetic biology Tissue engineering

A new portable open-path instrument for ambient NH_(3) and on-road emission measurements

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Journal of Environmental Sciences 2024年第2期136卷 606-614页

作者： Wenhao dai Shanshan wang Sanbao Zhang Jian Zhu Chuanqi Gu Zhibin Sun Ruibin Xue Bin zhou Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Institute of Eco-Chongming(IEC) Shanghai 202162China Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China

Increased attentions to vehicle emission of NH_(3)have been paid since it is generally regarded as an important source in urban areas.Here,we developed a movable instrument based on Differential Optical Absorption Spectroscopy(DOAS)principle for detecting on-road NH_(3),which can avoid the losses in the sampling process attributed to the non-sampling methods.For this mobile DOAS,the temporal resolution,detection limit and relative error for NH_(3)were 1 min,2.29 ppbv and 4.57%±2.44%,respectively.By employed to the on-road measurements along the arterial highway in Shanghai,the spatial distributions of NH_(3)and NO were obtained,and their dependence of traffic and road conditions were studied.The slopes of linear regression between NH_(3)and NO were 0.40,0.02 and 0.07 on the Middle Ring Road,Outer Ring Road and Chongming Island Ring Road.It indicates that light gasoline vehicles(LGVs)were found to be the main contributor to NH_(3)emissions,while heavy-duty diesel vehicles(HDVs)mainly emitted NO.Based on the measured NH_(3)in the tunnel,the mileagebased NH_(3)emission factor per vehicle was estimated to be 17.9±6.3 mg/km.The reported open-path instrument can be broadly used in on-road pollutant monitoring or vehicle emissions,and the measurements can reveal the real situation of emission characteristics,even find the abnormal operations of vehicle catalyst system.

关键词： Ammonia Traffic emissions DOAS Emission factor Mobile measurements