Previous studies show that temporal irreversibility(TI),as an important indicator of the nonlinearity of time series,is almost uniformly overestimated in the daily air temperature anomaly series over China in NCEP rea...Previous studies show that temporal irreversibility(TI),as an important indicator of the nonlinearity of time series,is almost uniformly overestimated in the daily air temperature anomaly series over China in NCEP reanalysis data,as compared with station observations.Apart from this highly overestimated TI in the NCEP reanalysis,some other important atmospheric metrics,such as predictability and extreme events,might also be overestimated since there are close relations between nonlinearity and predictability/extreme events.In this study,these issues are fully addressed,i.e.,intrinsic predictability,prediction skill,and the number of extreme events.The results show that intrinsic predictability,prediction skill,and the occurrence number of extreme events are also almost uniformly overestimated in the NCEP reanalysis daily minimum and maximum air temperature anomaly series over China.Furthermore,these overestimations of intrinsic predictability,prediction skill,and the number of extreme events are only weakly correlated with the overestimated TI,which indicates that the quality of the NCEP reanalysis should be carefully considered when conclusions on both predictability and extreme events are derived.展开更多
Tendon calcification is a common clinical condition that frequently occurs as a complication after tendon injury and surgery,or as an expression of fibrodysplasia ossificans progressiva.This condition can be referred ...Tendon calcification is a common clinical condition that frequently occurs as a complication after tendon injury and surgery,or as an expression of fibrodysplasia ossificans progressiva.This condition can be referred to by various names in clinical practice and literature,including tendon ossification,tendon mineralization,heterotopic ossification,and calcific tendonitis.The exact pathogenesis of tendon calcification remains uncertain,but current mainstream research suggests that calcification is mostly cell mediated.To further elucidate the pathogenesis of tendon calcification and to better simulate the overall process,selecting appropriate experimental animal models is important.Numerous animal models have been utilized in various clinical studies,each with its own set of advantages and limitations.In this review,we have discussed the advancements made in research on animal models of tendon calcification,with a focus on the selection of experimental animals,the sites of injury in these models,and the methods employed for modeling.展开更多
Robust three-dimensional(3D)recognition across different viewing angles is crucial for dynamic applications such as autonomous navigation and augmented reality;however,the application of the technology remains challen...Robust three-dimensional(3D)recognition across different viewing angles is crucial for dynamic applications such as autonomous navigation and augmented reality;however,the application of the technology remains challenging owing to factors such as orientation,deformation,and noise.Wave-based analogous computing,particularly diffraction neural networks(DNNs),constitutes a scan-free,energy-efficient means of mitigating these issues with strong resilience to environmental disturbances.Herein,we present a real-time all-directional 3D object recognition and distortion correction system using a deep knowledge prior DNN.Our approach effectively addressed complex two-dimensional(2D)and 3D distortions by optimizing the metasurface parameters with minimal training data and refining them using DNNs.Experimental results demonstrate that the system can effectively rectify distortions and recognize objects in real time,even under varying perspectives and multiple complex distortions.In 3D recognition,the prior DNN reliably identifies both dynamic and static objects,maintaining stable performance despite arbitrary orientation changes,highlighting its adaptability to complex and dynamic environments.Our system can function either as a preprocessing tool for imaging platforms or as a stand-alone solution,facilitating 3D recognition tasks such as motion sensing and facial recognition.It offers a scalable solution for high-speed recognition tasks in dynamic and resource-constrained applications.展开更多
Porous organic polymers(POPs)are promising candidates for catalyzing the hydrogen evolution reaction(HER)and the oxygen reduction reaction(ORR)owing to their tunable porous structures and abundant chemical reaction ch...Porous organic polymers(POPs)are promising candidates for catalyzing the hydrogen evolution reaction(HER)and the oxygen reduction reaction(ORR)owing to their tunable porous structures and abundant chemical reaction channels/active centers.However,insufficient conductivities limit their practical applications in the HER/ORR.The challenge is to construct conductive POPs with highly efficient HER/ORR performance.Herein,a series of metal-free corrole-based donor–acceptor POPs(Cor-D–A-POPs)as bifunctional HER/ORR catalysts have been designed and constructed from 5,10,15-tris(p-aminophenyl)corrole(TPAPC)and 2,2’-bithiophene-5,5’-dialdehyde(BTDA)or 2,5-thiophenedialdehyde(TDA)with a donor–acceptor method.Compared with Cor-D–A-POPs using TDA as an electron donor(Cor-TDA-D–A-POPs),Cor-D–A-POPs using BTDA as an electron donor(Cor-BTDA-D–A-POPs)exhibit higher HER/ORR activities due to their more favorable charge transfer ability from the BTDA donor to the TPAPC acceptor.The integration of high surface area,rich accessible catalytic sites,and high conductivity makes Cor-BTDA-D–A-POP-1 constructed in a mixed solvent of n-butanol/mesitylene(1:1)exhibit optimal HER/ORR activities in alkaline solution,with a comparable HER overpotential of 0.10 V at 10 mA cm^(−2)and an ORR Tafel slope of 90.0 mV dec−1 to Pt/C(0.09 V and 88.0 mV dec^(−1)).Moreover,its HER/ORR stability is superior to that of Pt/C.The experimental results are consistent with density functional theory calculations.Therefore,the combination of suitable electron donors and electron acceptors can promote charge transfer within POPs and generate high activities for the HER/ORR.展开更多
高频超声换能器已成为现代医学诊断和治疗的有力工具.目前,大多数超声换能器使用压电陶瓷进行机电耦合,在高频(>20 MHz)下会发生周期性的电声转换,因此对材料可靠性要求较高.本文提出了一种结构调控策略,以提高铌酸钾钠(KNN)基无铅...高频超声换能器已成为现代医学诊断和治疗的有力工具.目前,大多数超声换能器使用压电陶瓷进行机电耦合,在高频(>20 MHz)下会发生周期性的电声转换,因此对材料可靠性要求较高.本文提出了一种结构调控策略,以提高铌酸钾钠(KNN)基无铅陶瓷的压电性与可靠性,并用于高频超声成像.该KNN基陶瓷具有增强的压电性(d33~550±20 pC N^(-1))及抗疲劳特性,同时针对其良好性能,我们从涉及宏观到微观的多项共存、完好微观结构与灵活畴翻转的多维度协同效应阐述其机理.该多维度协同效应抑制了疲劳过程中性能恶化裂纹的出现及空间电荷的聚集,从而减少了畴壁的钉扎,增强了抗疲劳性.此外,基于该高性能压电陶瓷制备的超声换能器具有高可靠性及温度稳定性(从室温到80℃,频带宽度几乎不变).我们利用该超声换能器扫描罗非鱼眼球结构测试了器件成像效果.相信通过结构策略实现性能提升的新方法可以促进KNN基超声器件在生物医学方面的应用.展开更多
基金funded by the National Natural Science Foundation of China[grant numbers 41475048,41675049,41705041]。
文摘Previous studies show that temporal irreversibility(TI),as an important indicator of the nonlinearity of time series,is almost uniformly overestimated in the daily air temperature anomaly series over China in NCEP reanalysis data,as compared with station observations.Apart from this highly overestimated TI in the NCEP reanalysis,some other important atmospheric metrics,such as predictability and extreme events,might also be overestimated since there are close relations between nonlinearity and predictability/extreme events.In this study,these issues are fully addressed,i.e.,intrinsic predictability,prediction skill,and the number of extreme events.The results show that intrinsic predictability,prediction skill,and the occurrence number of extreme events are also almost uniformly overestimated in the NCEP reanalysis daily minimum and maximum air temperature anomaly series over China.Furthermore,these overestimations of intrinsic predictability,prediction skill,and the number of extreme events are only weakly correlated with the overestimated TI,which indicates that the quality of the NCEP reanalysis should be carefully considered when conclusions on both predictability and extreme events are derived.
基金the Science and Technology Innovation Cooperation Special Programme of Sichuan Province,Grant/Award Number:2022YFS0609-C1Industry-University-Research Cooperation Foundation,Grant/Award Number:2021CXYZ01+2 种基金Luzhou Science and Technology Plan Project,Grant/Award Number:2021-SYF-25China Postdoctoral Science Foundation,Grant/Award Number:2023M732927Scientific Research Project of Southwest Medical University,Grant/Award Number:2021ZKMS051 and 2022QN018。
文摘Tendon calcification is a common clinical condition that frequently occurs as a complication after tendon injury and surgery,or as an expression of fibrodysplasia ossificans progressiva.This condition can be referred to by various names in clinical practice and literature,including tendon ossification,tendon mineralization,heterotopic ossification,and calcific tendonitis.The exact pathogenesis of tendon calcification remains uncertain,but current mainstream research suggests that calcification is mostly cell mediated.To further elucidate the pathogenesis of tendon calcification and to better simulate the overall process,selecting appropriate experimental animal models is important.Numerous animal models have been utilized in various clinical studies,each with its own set of advantages and limitations.In this review,we have discussed the advancements made in research on animal models of tendon calcification,with a focus on the selection of experimental animals,the sites of injury in these models,and the methods employed for modeling.
基金supported by the National Key Research and Development Program of China (Grant Nos. 2022YFA1404704, 2022YFA1405200, and 2022YFA1404902)the National Natural Science Foundation of China (NNSFC) (Grant Nos. 61975176 and 62071423)+3 种基金the Key Research and Development Program of Zhejiang Province (Grant Nos. 2022C01036 and 2024C01160)the Natural Science Foundation of Zhejiang Province (Grant No. LR23F010004)the Top-Notch Young Talent of Zhejiang Provincethe Fundamental Research Funds for the Central Universities
文摘Robust three-dimensional(3D)recognition across different viewing angles is crucial for dynamic applications such as autonomous navigation and augmented reality;however,the application of the technology remains challenging owing to factors such as orientation,deformation,and noise.Wave-based analogous computing,particularly diffraction neural networks(DNNs),constitutes a scan-free,energy-efficient means of mitigating these issues with strong resilience to environmental disturbances.Herein,we present a real-time all-directional 3D object recognition and distortion correction system using a deep knowledge prior DNN.Our approach effectively addressed complex two-dimensional(2D)and 3D distortions by optimizing the metasurface parameters with minimal training data and refining them using DNNs.Experimental results demonstrate that the system can effectively rectify distortions and recognize objects in real time,even under varying perspectives and multiple complex distortions.In 3D recognition,the prior DNN reliably identifies both dynamic and static objects,maintaining stable performance despite arbitrary orientation changes,highlighting its adaptability to complex and dynamic environments.Our system can function either as a preprocessing tool for imaging platforms or as a stand-alone solution,facilitating 3D recognition tasks such as motion sensing and facial recognition.It offers a scalable solution for high-speed recognition tasks in dynamic and resource-constrained applications.
基金supported by the National Natural Science Foundation of China(Grant No.52271251)the Henan Provincial Science and Technology Research Project(Grant No.222102230050)the Doctoral Startup Fund of Xinxiang Medical University(Grant No.XYBSKYZZ201507).
文摘Porous organic polymers(POPs)are promising candidates for catalyzing the hydrogen evolution reaction(HER)and the oxygen reduction reaction(ORR)owing to their tunable porous structures and abundant chemical reaction channels/active centers.However,insufficient conductivities limit their practical applications in the HER/ORR.The challenge is to construct conductive POPs with highly efficient HER/ORR performance.Herein,a series of metal-free corrole-based donor–acceptor POPs(Cor-D–A-POPs)as bifunctional HER/ORR catalysts have been designed and constructed from 5,10,15-tris(p-aminophenyl)corrole(TPAPC)and 2,2’-bithiophene-5,5’-dialdehyde(BTDA)or 2,5-thiophenedialdehyde(TDA)with a donor–acceptor method.Compared with Cor-D–A-POPs using TDA as an electron donor(Cor-TDA-D–A-POPs),Cor-D–A-POPs using BTDA as an electron donor(Cor-BTDA-D–A-POPs)exhibit higher HER/ORR activities due to their more favorable charge transfer ability from the BTDA donor to the TPAPC acceptor.The integration of high surface area,rich accessible catalytic sites,and high conductivity makes Cor-BTDA-D–A-POP-1 constructed in a mixed solvent of n-butanol/mesitylene(1:1)exhibit optimal HER/ORR activities in alkaline solution,with a comparable HER overpotential of 0.10 V at 10 mA cm^(−2)and an ORR Tafel slope of 90.0 mV dec−1 to Pt/C(0.09 V and 88.0 mV dec^(−1)).Moreover,its HER/ORR stability is superior to that of Pt/C.The experimental results are consistent with density functional theory calculations.Therefore,the combination of suitable electron donors and electron acceptors can promote charge transfer within POPs and generate high activities for the HER/ORR.
基金supported by the National Natural Science Foundation of China(NSFC 52202144,52061130216 and 52032007)the Key-Area Research and Development Program of Guangdong Province(2020B0109380001)+2 种基金the Central Funds Guiding the Local Science and Technology Development of Sichuan Province(2021ZYD0022)the Fundamental Research Funds for the Central Universities,Sichuan University(YJ2021153)the Newton Advanced Fellowship award(NAFR1201126)from the Royal Society。
文摘高频超声换能器已成为现代医学诊断和治疗的有力工具.目前,大多数超声换能器使用压电陶瓷进行机电耦合,在高频(>20 MHz)下会发生周期性的电声转换,因此对材料可靠性要求较高.本文提出了一种结构调控策略,以提高铌酸钾钠(KNN)基无铅陶瓷的压电性与可靠性,并用于高频超声成像.该KNN基陶瓷具有增强的压电性(d33~550±20 pC N^(-1))及抗疲劳特性,同时针对其良好性能,我们从涉及宏观到微观的多项共存、完好微观结构与灵活畴翻转的多维度协同效应阐述其机理.该多维度协同效应抑制了疲劳过程中性能恶化裂纹的出现及空间电荷的聚集,从而减少了畴壁的钉扎,增强了抗疲劳性.此外,基于该高性能压电陶瓷制备的超声换能器具有高可靠性及温度稳定性(从室温到80℃,频带宽度几乎不变).我们利用该超声换能器扫描罗非鱼眼球结构测试了器件成像效果.相信通过结构策略实现性能提升的新方法可以促进KNN基超声器件在生物医学方面的应用.
