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Visible-frequency nonvolatile reconfigurable Janus metasurfaces for dual-wavelength-switched and spin-asymmetric holograms

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Photonics Research 2024年第2期12卷 356-368页

作者： HUAN yuan ZHEQIANG zhong BIN ZHANG College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Big Data Analysis and Fusion Application Technology Engineering Laboratory of Sichuan Province Chengdu 610065China

Janus metasurface holography with asymmetric transmission characteristics provides new degrees of freedom for multiplexing technologies.However,earlier metasurfaces with asymmetrical transmission faced limitations in terms of tunability and multifunctionality.In this study,we propose a metasurface color holographic encryption scheme with dynamic switching and asymmetric transmission at visible frequencies using a low-loss nonvolatile optical phase-change material,Sb_(2)S_(3).Using a modified holographic optimization strategy,we achieved highfidelity asymmetric holographic imaging of a nanostructured metasurface.By controlling the incident direction and wavelength of visible light,as well as the level of crystallization of Sb_(2)S_(3),this reconfigurable metasurface enables the precise manipulation of tunable color holographic image displays.In particular,in the semi-crystalline state of Sb_(2)S_(3),the encoded information can be securely encrypted using a two-channel color-holographic image,whereas only a preset camouflaged image is displayed in the crystalline or amorphous state of Sb_(2)S_(3).The proposed multiencrypted Janus metasurface provides a potential approach for dynamic holographic displays with ultrahigh capacity,holographic encryption,and information storage.

关键词： holographic asymmetric visible

A Lightweight Network with Dual Encoder and Cross Feature Fusion for Cement Pavement Crack Detection

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 255-273页

作者： zhong Qu Guoqing Mu Bin yuan School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing400065China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

Automatic crack detection of cement pavement chiefly benefits from the rapid development of deep learning,with convolutional neural networks(CNN)playing an important role in this field.However,as the performance of crack detection in cement pavement improves,the depth and width of the network structure are significantly increased,which necessitates more computing power and storage space.This limitation hampers the practical implementation of crack detection models on various platforms,particularly portable devices like small mobile devices.To solve these problems,we propose a dual-encoder-based network architecture that focuses on extracting more comprehensive fracture feature information and combines cross-fusion modules and coordinated attention mechanisms formore efficient feature fusion.Firstly,we use small channel convolution to construct shallow feature extractionmodule(SFEM)to extract low-level feature information of cracks in cement pavement images,in order to obtainmore information about cracks in the shallowfeatures of images.In addition,we construct large kernel atrous convolution(LKAC)to enhance crack information,which incorporates coordination attention mechanism for non-crack information filtering,and large kernel atrous convolution with different cores,using different receptive fields to extract more detailed edge and context information.Finally,the three-stage feature map outputs from the shallow feature extraction module is cross-fused with the two-stage feature map outputs from the large kernel atrous convolution module,and the shallow feature and detailed edge feature are fully fused to obtain the final crack prediction map.We evaluate our method on three public crack datasets:DeepCrack,CFD,and Crack500.Experimental results on theDeepCrack dataset demonstrate the effectiveness of our proposed method compared to state-of-the-art crack detection methods,which achieves Precision(P)87.2%,Recall(R)87.7%,and F-score(F1)87.4%.Thanks to our lightweight crack detectionmodel,the parameter count of the mo

关键词： Shallow feature extraction module large kernel atrous convolution dual encoder lightweight network crack detection

In vivo label-free measurement of blood flow velocity symmetry based on dual line scanning third-harmonic generation microscopy excited at the 1700 nm window

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 61-68页

作者： hui Cheng Jincheng zhong Ping Qiu Ke Wang Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen 518060 P.R.China

Measurement of bloodflow velocity is key to understanding physiology and pathology in vivo.While most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the instantaneous bloodflow velocity distribution.This is mainly due to the lack of measurement technology with high spatial and temporal resolution.Here,we tackle this problem with our recently developed dual-wavelength line-scan third-harmonic generation(THG)imaging technology.Simultaneous acquisition of dual-wavelength THG line-scanning signals enables measurement of bloodflow velocities at two radially symmetric positions in both venules and arterioles in mouse brain in vivo.Our results clearly show that the instantaneous bloodflow velocity is not symmetric under general conditions.

关键词： 1700 nm-Window third-harmonic generation imaging blood flow velocity

Polyoxometalates-derived ternary metal oxides electrocatalyst for N_(2) reduction under ambient conditions

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Tungsten 2024年第2期6卷 428-437页

作者： Meng-Le Yang zhong-Xin Jin Xi-Xian Cao Xin-Ming Wang hui-yuan Ma Hai-Jun Pang Gui-Xin Yang The School of Material Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150040China

Accelerating the breaking of the nitrogen nonpolar bond(N≡N)is an important factor to improve the effi ciency of the electro-catalytic nitrogen reduction reaction(e-NRR).In this work,polyoxometalates-derived FeMo-based ternary oxide materials MoO_(2)-Mo_(4)O_(11)-FeMoO_(4)@X(abbreviated as MoFeO@X,X represents the synthesis temperature of 650,750 and 850℃)were designed and synthesized for e-NRR under ambient conditions.The scanning electron microscopy images of MoFeO@750 show an ellipsoidal-like structure(0.86×0.6μm).The relatively large specifi c surface area,formation of multiple interfaces,together with the synergistic eff ect of iron and molybdenum bimetals,would make MoFeO@X catalyst more easily absorb and activate N_(2)in the e-NRR.Expectedly,the synthesized MoFeO@750 shows an optimal NH_(3)production rate of 16.57μg·h^(−1)·mg cat.^(−1)and Faradaic effi ciency of 12.33%at−0.3 V versus reversible hydrogen electrode(νs.RHE),with outstanding electrochemical and structural stability.

关键词： Polyoxometalates Electrocatalytic nitrogen reduction reaction Ternary oxide Electrocatalyst

Granular Ionogel Particle Inks for 3D Printed Tough and Stretchable Ionotronics

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Research 2024年第1期2023卷 429-442页

作者： yuan Yao Yue hui Zhenhua Wang Hehao Chen Heng Zhu Nanjia Zhou Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024Zhejiang ProvinceChina Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024Zhejiang ProvinceChina School of Chemical Engineering and Advanced Materials the University of AdelaideAdelaide 5005South AustraliaAustralia State Key Laboratory of Fluid Power&Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceCenter for X-MechanicsDepartment of Engineering MechanicsZhejiang UniversityHangzhou 310027China

Ionogels have garnered great attention as promising soft conducting materials for the fabrication of flexible energy storage devices,soft actuators,and ionotronics.However,the leakage of the ionic liquids,weak mechanical strength,and poor manufacturability have greatly limited their reliability and applications.Here,we propose a new ionogel synthesis strategy by utilizing granular zwitterionic microparticles to stabilize ionic liquids.The ionic liquids swell the microparticles and physically crosslink microparticles via either electronic interaction or hydrogen bonding.Further introducing a photocurable acrylic monomer enables the fabrication of double-network(DN)ionogels with high stretchability(>600%)and ultrahigh toughness(fracture energy>10 kJ/m^(2)).The synthesized ionogels exhibit a wide working temperature of−60 to 90℃.By tuning the crosslinking density of microparticles and physical crosslinking strength of ionogels,we synthesize DN ionogel inks and print them into three-dimensional(3D)motifs.Several ionogelbased ionotronics are 3D printed as demonstrations,including strain gauges,humidity sensors,and ionic skins made of capacitive touch sensor arrays.Via covalently linking ionogels with silicone elastomers,we integrate the ionogel sensors onto pneumatic soft actuators and demonstrate their capacities in sensing large deformation.As our last demonstration,multimaterial direct ink writing is harnessed to fabricate highly stretchable and durable alternating-current electroluminescent devices with arbitrary structures.Our printable granular ionogel ink represents a versatile platform for the future manufacturing of ionotronics.

关键词： crosslinking utilizing gauge

Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis

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General Psychiatry 2024年第2期37卷 177-188页

作者： Meng-Di yuan Jun-Fa Liu Bao-Liang zhong Research Center for Psychological and Health Sciences China University of Geosciences(Wuhan)WuhanHubeiChina Department of Psychiatry Wuhan Mental Health CentreWuhanHubeiChina

Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in China.Methods We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese individuals.The risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),respectively.The‘metaprop’package in R V.4.1.2 was used to synthesise the prevalence.Results A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and 7.The combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),respectively.PGD and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),respectively.The GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its symptoms.Conclusions The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in China.This need is particularly pronounced in those who have lost their only child and those bereaved due to earthquakes.Further methodologically rigorous studies are needed to provide more accurate prevalence estimates.PROSPERO registration number CRD42023432553.

关键词： symptoms prevalence analysis

Numerical simulation of transient characteristics in a bulb turbine during the load rejection process

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Journal of Hydrodynamics 2024年第1期36卷 170-183页

作者： Yue Lu Yu-quan Zhang zhong-wei He yuan Zheng College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China College of Energy and Electrical Engineering Hohai UniversityNanjing210098China Huadong Engineering Corporation Ltd. Hangzhou311122China

To evaluate the safety of the bulb tubular turbine,the dynamic hydraulic characteristics of a hydropower station system during the load rejection process are studied through numerical simulations and a prototype test.In the developed model,a dynamic grid technology(DGT)controls the closure of the guide vane and the blade,whilst the moment balance equation and the user-defined function(UDF)provide the runner’s rotation speed.The 3-D transient simulation method can well predict the rotation speed and mass flow curves in the state of load rejection.The simulation outcomes of the system performance are basically consistent with the measurement data of the prototype.As observed,the runner is subjected to the reversely increased torque and axial force,the system is in a braking phase,and the maximum speed peaks at 144.6%of the rated speed.Moreover,the internal flow of the runner is greatly affected by the closure of the guide vane,and the draft tube forms an eccentric spiral vortex rope.It breaks downstream,aggravating the instability of the draft tube.Overall,the transient characteristics span for the first five seconds,demonstrating the importance of establishing an efficient governing controller.The obtained results are useful for designing the turbine’s flow channel with a double regulating function and comprehending the turbine’s transient characteristics.

关键词： Bulb tubular turbine load rejection numerical simulation dynamic grid prototype test

Efficacy of exercise rehabilitation for managing patients with Alzheimer's disease

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Neural Regeneration Research 2024年第10期19卷 2175-2188页

作者： Dan Li Jinning Jia Haibo Zeng Xiaoyan zhong hui Chen Chenju Yi Department of Pathology The First Affiliated Hospital of Gannan Medical UniversityGanzhouJiangxi ProvinceChina Department of Pathology Huichang County People’s HospitalGanzhouJiangxi ProvinceChina School of Life Sciences Faculty of ScienceUniversity of Technology SydneyUltimoNSWAustralia Research Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhenGuangdong ProvinceChina Shenzhen Key Laboratory of Chinese Medicine Active Substance Screening and Translational Research ShenzhenGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Brain Function and Disease GuangzhouGuangdong ProvinceChina

Alzheimer's disease(AD) is a progressive and degenerative neurological disease characterized by the deterioration of cognitive functions. While a definitive cure and optimal medication to impede disease progression are currently unavailable, a plethora of studies have highlighted the potential advantages of exercise rehabilitation for managing this condition. Those studies show that exercise rehabilitation can enhance cognitive function and improve the quality of life for individuals affected by AD. Therefore, exercise rehabilitation has been regarded as one of the most important strategies for managing patients with AD. Herein, we provide a comprehensive analysis of the currently available findings on exercise rehabilitation in patients with AD, with a focus on the exercise types which have shown efficacy when implemented alone or combined with other treatment methods, as well as the potential mechanisms underlying these positive effects. Specifically, we explain how exercise may improve the brain microenvironment and neuronal plasticity. In conclusion, exercise is a cost-effective intervention to enhance cognitive performance and improve quality of life in patients with mild to moderate cognitive dysfunction. Therefore, it can potentially become both a physical activity and a tailored intervention. This review may aid the development of more effective and individualized treatment strategies to address the challenges imposed by this debilitating disease, especially in low-and middle-income countries.

关键词： Alzheimer's disease cerebrovascular function cognitive function epigenetic regulation exercise hippocampal neurogenesis mitochondria neuroinflammation neuronal plasticity

Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens

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Food Science and Human Wellness 2024年第3期13卷 1567-1577页

作者： yuan yuan Shun zhong Zeyuan Deng Guangyan Li Jinwu Zhang Hongyan Li State Key Laboratory of Food Science and Resources Nanchang UniversityNanchang 330047China Nanchang Tongxin Zichao Biological Engineering Co. Ltd.Nanchang 330052China

The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods.

关键词： Bee pollen Nutrients Wall disruption Phenolic compounds In vitro digestion