Tailoring spatiotemporal dynamics of plasmonic vortices

Plasmonic vortices confining orbital angular momentums to surface have aroused wide research interest in the last decade.Recent advances of near-field microscopes have enabled the study on the spatiotemporal dynamics of plasmonic vortices,providing a better understanding of optical orbital angular momentums in the evanescent wave regime.However,these works only focused on the objective characterization of plasmonic vortex and have not achieved subjectively tailoring of its spatiotemporal dynamics for specific applications.Herein,it is demonstrated that the plasmonic vortices with the same topological charge can be endowed with distinct spatiotemporal dynamics by simply changing the coupler design.Based on a near-field scanning terahertz microscopy,the surface plasmon fields are directly obtained with ultrahigh spatiotemporal resolution,experimentally exhibiting the generation and evolution divergences during the whole lifetime of plasmonic vortices.The proposed strategy is straightforward and universal,which can be readily applied into visible or infrared frequencies,facilitating the development of plasmonic vortex related researches and applications.

Time-Domain Protection for Transmission Lines Connected to Wind Power Plant based on Model Matching and Hausdorff Distance

The system impedance instability,high-order harmonics,and frequency offset are main fault characteristics of wind power system.Moreover,the measurement angle of faulty phase is affected by rotation speed frequency component,which causes traditional directional protections based on angle comparison between voltage and current to operate incorrectly.In this paper,a time-domain protection for connected to wind power plant based on model matching is proposed,which compares the calculated current and the measured current to identify internal faults and external faults.Under external faults,the calculated current and measured current waveform are quite similar because the protected transmission lines is equivalent to a lumped parameter model and the model itself is not damaged.However,the similarity of calculated current and measured current is quite low,due to destroyed integrity of model under internal faults.Additionally,Hausdorff distance is introduced to obtain the similarity of the calculated current and measured current.Since the proposed protection scheme is applied in time domain,it is independent from current frequency offsets of wind energy system,high-order harmonics,and system impedance variations.Comprehensive case studies are undertaken through Power Systems Computer Aided Design(PSCAD),while simulation results verify the accuracy and efficiency of the proposed approach in fault identification.

On-chip terahertz orbital angular momentum demultiplexer

The terahertz regime is widely recognized as a fundamental domain with significant potential to address the demands of next-generation wireless communications.In parallel,mode division multiplexing based on orbital angular momentum(OAM)shows promise in enhancing bandwidth utilization,thereby expanding the overall communication channel capacity.In this study,we present both theoretical and experimental demonstrations of an on-chip terahertz OAM demultiplexer.This device effectively couples and steers seven incident terahertz vortex beams into distinct high-quality focusing surface plasmonic beams,and the focusing directions can be arbitrarily designated.The proposed design strategy integrates space-to-chip mode conversion,OAM recognition,and on-chip routing in a compact space with subwavelength thickness,exhibiting versatility and superior performance.

Reconfigurable and nonvolatile terahertz lithography-free photonic devices based on phase change films

High-performance terahertz(THz)devices with reconfigurable features are highly desirable in many promising THz applications.However,most of the existing reconfigurable THz elements are still limited to volatile responses,single functionality,and time-consuming multistep manufacturing procedures.In this paper,we report a lithography-free approach to create reconfigurable and nonvolatile THz components by exploring the reversible,nonvolatile,and continuous THz modulation capability of the phase change material Ge_(2)Sb_(2)Te_(5).As a proof of concept,THz gratings with significant Rayleigh anomalies and diffraction as well as ultrathin THz flat lenses with subwavelength and ultra-broadband focusing capabilities are designed and fabricated on ultrathin Ge_(2)Sb_(2)Te_(5)films using the presented photo-imprint strategy.Moreover,such a method can also be adopted to create more complex THz devices,such as Pancharatnam–Berry phase metasurfaces and grayscale holographic plates.With these findings,the proposed method will provide a promising solution to realize reconfigurable and nonvolatile THz elements.

Meta-optics inspired surface plasmon devices

Surface plasmons(SPs)are electromagnetic surface waves that propagate at the interface between a conductor and a dielectric.Due to their unique ability to concentrate light on two-dimensional platforms and produce very high local-field intensity,SPs have rapidly fueled a variety of fundamental advances and practical applications.In parallel,the development of metamaterials and metasurfaces has rapidly revolutionized the design concepts of traditional optical devices,fostering the exciting field of meta-optics.This review focuses on recent progress of meta-optics inspired SP devices,which are implemented by the careful design of subwavelength structures and the arrangement of their spatial distributions.Devices of general interest,including coupling devices,on-chip tailoring devices,and decoupling devices,as well as nascent SP applications empowered by sophisticated usage of meta-optics,are introduced and discussed.

Fast Protection for Collector Lines in Large-Scale Wind Farms Based on Random Matrix Theory

The impact of large-scale wind farms on power system stability should be carefully investigated,in which mal-functions usually exist in the collector line's relay protection.In order to solve this challenging problem,a novel time-domain protection scheme for collector lines,based on random matrix theory(RMT),is proposed in this paper.First,the collected currents are preprocessed to form time series data.Then,a real-time sliding time window is used to form a consecutive time series data matrix.Based on RMT,mean spectral radius(MSR)is used to analyze time series data characteristics after real-time calculations are performed.Case studies demonstrate that RMT is independent from fault locations and fault types.In particular,faulty and non-faulty collector lines can be accurately and efficiently identified compared with traditional protection schemes.

红景天苷对NMDA介导的小鼠视网膜神经节细胞损伤的保护作用

目的:探讨红景天苷(Sal)对视网膜神经节细胞(RGCs)凋亡的抑制作用。方法:实验研究。36只C57BL6J小鼠随机分为空白组、模型对照组、不同浓度Sal实验组,每组6只,均以右眼为实验眼。空白组仅注射0.9%PBS溶液,模型对照组和实验组玻璃体腔注射N-甲基-D-天(门)冬氨酸(NMDA)1.5μl建立RGCs损伤模型;建模前48h,模型对照组注射1.5μl0.9%PBS溶液,实验组玻璃体腔注射不同浓度Sal(0.1、0.4、2、8mmol/L,1.5μl)。建模5d后制备视网膜标本,观察视网膜RGCs存活及凋亡情况,WesternBlot法检测视网膜中Caspase-3、Caspase-8蛋白的表达。数据采用单因素方差分析。结果:HE染色显示空白组视网膜RGCs无变化,模型对照组RGCs显著减少,不同浓度Sal实验组RGCs细胞核染色数目较模型对照组逐渐增加,并呈浓度依赖性;经视网膜平铺片测定RGCs存活情况,发现空白组RGCs正常存活,模型对照组仅少量RGCs存活,不同浓度Sal组RGCs存活率较模型对照组提高,各组小鼠RGCs阳性细胞数比较差异有统计学意义(F=212.0,P<0.001)。同时,8mmol/L浓度的Sal实验组Caspase-3、Caspase-8蛋白表达明显低于模型对照组,差异有统计学意义(F=168.3,P<0.001)。结论:Sal可以抑制NMDA介导的RGCs凋亡,对RGCs损伤有保护作用。

浅谈程锦国主任医师从慢惊风论治小儿抽动障碍

儿童抽动障碍因其症状特点常就诊于眼科。程锦国主任医师认为儿童抽动障碍尤其是慢性抽动障碍、抽动秽语综合征与小儿"慢惊风"之病因病机一致,二者均以土虚木乘,脾虚肝旺为基本病机,生痰动风为主要病理表现,惊风、抽搐为具体体现形式。同时程锦国主任医师认为在治法和方药方面亦有可借鉴治疗慢惊风之经验,或自制疏肝健脾、化痰熄风方;或视病机之不同灵活组方,累获良效。现结合医案总结了儿童抽动障碍的临床特点及程锦国主任医师治疗本病的经验。

眼轮匝肌平行直刺联合眼周穴位针刺法治疗偏侧面肌痉挛的临床疗效

目的:观察眼轮匝肌平行直刺联合眼周穴位针刺法治疗偏侧面肌痉挛患者的疗效,为治疗面肌痉挛提供理论依据。方法:系列病例研究。收集2018年12月至2020年12月在温州医科大学附属眼视光医院中医眼科门诊诊断为偏侧面肌痉挛的患者60例,按照随机数字表法分为治疗组和对照组,每组30例。治疗组接受眼轮匝肌平行直刺联合眼周穴位针刺法;对照组口服盐酸硫必利片、银杏叶胶囊、甲钴胺胶囊。2组患者治疗2周后根据Cohen评分表评价面肌痉挛严重程度及频率。患者痉挛严重程度及频率分级在治疗前后的比较采用t检验或秩和检验。结果:治疗2周后,治疗组与对照组患者面肌痉挛分级程度均有一定的下降。与治疗前相比,治疗组患者痉挛强度及频率分级的比较差异有统计学意义(Z=-2.67,P=0.008;Z=-2.45,P=0.014);对照组虽然面肌痉挛强度有一定的下降,但治疗前后差异无统计学意义。治疗组较对照组痉挛强度及频率分级改善明显,差异有统计学意义(t=-2.04,P=0.042;t=-1.99,P=0.047);治疗组总有效率为87%;对照组总有效率为53%,2组差异有统计学意义(χ^(2)=11.81,P=0.008)。随访3个月后,治疗组中有1例复发,复发率为3%;对照组中有6例复发,复发率20%,2组差异有统计学意义(χ^(2)=4.04,P=0.044)。结论:眼轮匝肌平行直刺联合眼周穴位针刺法在治疗面肌痉挛方面有良好且确定的疗效,并且可以最大限度改善面肌痉挛症状,疗效优于传统治疗方法,适合临床应用。

胡臻主任应用升阳疗法治疗眼科疾病举隅

升阳疗法是治疗眼科疾病的常用治法,可配合益气、健脾、疏肝、活血、利水、清热、补肾等灵活应用。临床用药以升麻、葛根、羌活、防风、川芎、柴胡等最为多见。升阳疗法在干眼合并眼睑痉挛、中心性浆液性脉络膜视网膜病变、葡萄膜炎、动眼神经麻痹等疾病诊治中均获得较好疗效。现通过归纳总结胡臻主任升阳疗法理论及眼科疾病用药特点,并结合病案总结升阳疗法治疗眼科疾病经验。表明升阳疗法在治疗眼科疾病中应用广泛,疗效显著。

Nonvolatile reconfigurable dynamic Janus metasurfaces in the terahertz regime

Metasurfaces,especially tunable ones,have played a major role in controlling the amplitude,phase,and polarization of electromagnetic waves and attracted growing interest,with a view toward a new generation of miniaturized devices.However,to date,most existing reconfigurable devices are bounded in volatile nature with sustained external energy to maintain and single functionality,which restrict their further applications.Here,we demonstrate for the first time,to our knowledge,nonvolatile,reconfigurable,and dynamic Janus metasurfaces by incorporating phase-change material Ge_(2)Se_(2)Te_(5)(GST)in the terahertz(THz)regime.First,we experimentally show the reversible switching characteristic of GST on large areas by applying a single nanosecond laser pulse,which exhibits excellent contrast of THz properties in both states.Then,we present a multiplex metasurface scheme.In each metasurface,three sets of structures are adopted,in which two sets integrate GST.The effective structures can be reversely modulated by the amorphization and crystallization of GST.As a proof of concept,the dynamic beam splitter,bifocal metalens,dual-mode focusing optical vortex generators,and switchable metalens/focusing optical vortex generators are designed,fabricated,and experimentally characterized,and can be switched reversibly and repeatedly with the help of optical and thermal stimuli.Our scheme will pave the way toward the development of multifunctional and compact THz devices and may find use for applications in THz imaging,sensing,and communications.

眼轮匝肌平行刺法联合眼周穴位针刺治疗良性特发性眼睑痉挛疗效的观察

目的:观察眼轮匝肌平行刺法联合眼周穴位针刺治疗良性特发性眼睑痉挛的疗效。方法:系列病例研究。收集2019年1月至2020年12月就诊于温州医科大学附属眼视光医院中医眼科门诊良性特发性眼睑痉挛患者70例,随机分为观察组和对照组。观察组采用眼轮匝肌平行刺法联合眼周穴位针刺(眼轮匝肌平行刺法联合攒竹、丝竹空、太阳、风池等穴)治疗,对照组予眼周穴位针刺治疗。痉挛严重程度评分等级人数、痉挛频率评分等级人数、疗效比较使用卡方检验。结果:观察组35例中临床治愈3例,显效12例,有效17例,无效3例,总有效率为91%。对照组35例中临床治愈1例,显效5例,有效18例,无效11例,总有效率为69%,2组治疗效果比较差异有统计学意义(χ^(2)=8.48,P=0.037)。结论:眼轮匝肌平行刺法联合眼周穴位针刺治疗良性特发性眼睑痉挛疗效优于单纯眼周穴位针刺。

急性前葡萄膜炎中医体质与生存质量的相关性

目的:评估急性前葡萄膜炎患者中医体质与生存质量的相关性。方法:横断面研究。选取2014年12月至2017年12月于温州医科大学附属眼视光医院中医眼科专科就诊并经体质评分判定为病理体质的患者196例,应用中华生存质量量表进行生存质量评分。采用t检验及线性回归分析中医体质与生存质量评分各领域的相关性。结果:196例患者中单纯体质者147例,复合体质者49例。经广义线性回归分析,患者的不同体质类型及体质评分与中华生存质量量表评分有显著相关性,进一步分析发现体质评分与中华生存质量量表评分中的形、情有显著相关性(均P<0.05),与神无显著相关。经线性回归分析,不同类型中医体质中,气虚、痰湿、血瘀、阳虚、阴虚体质与中华生存质量量表中的形有显著相关性(均P<0.05);气郁体质与情有显著相关性(P=0.001);而湿热体质与形和情均有显著相关性(均P<0.001)。结论:急性前葡萄膜炎患者的不同中医体质与中医生存质量密切相关,且对形的影响最大。

Colonization of Penicillium oxalicum SL2 in Pb-contaminated paddy soil and its immobilization effect on soil Pb

Penicillium oxalicum SL2(SL2) is a previously screened Pb-tolerant fungus that can promote crops growth. The relationship between SL2 colonization and Pb immobilization was studied to provide a theoretical basis for microbial remediation of Pb-contaminated paddy soil.In this study, green fluorescent protein(GFP) labeled SL2 was inoculated into different Pbcontaminated paddy soils(S1-S6). The Pb extracted from the soil by HNO, EDTA and CaClwere used to characterize the available Pb. The results showed that the colonization of SL2was divided into lag phase(0-7 days), growth phase(7-30 days), and mortality phase(30-90days). SL2 colonized well in sandy soils rich in clay and total phosphorus with initial p H of 4.5-7.0. In addition, SL2 increased soil p H and decreased soil Eh, which was beneficial to immobilize Pb. In different soils, the highest percentages of CaCl-Pb, EDTA-Pb, and HNO3-Pb immobilized by SL2 were 34.34%-40.53%, 17.05%-20.11%, and 7.39%-15.62%, respectively.Pearson correlation analysis showed that the percentages of CaCl-Pb and EDTA-Pb immobilized by SL2 were significantly positively correlated with the number of SL2 during the growth phase. SL2 mainly immobilized Pb in the growth phase and a higher peak number of SL2 was beneficial to the immobilization of Pb.

基于中医学气血与络脉理论探析儿童青少年近视

近视是我国乃至全球重大公共卫生问题,中国儿童近视率居世界首位。近年来,中医药疗法特别是中医适宜技术在儿童青少年近视防控中发挥越来越重要的作用。一些学者对儿童青少年近视的中医病机提出了新的观点,推动了中医药防控近视的理论创新和发展。脉络膜、巩膜缺血缺氧学说是现代医学关于近视形成学说的重大发现,我们基于中医学络脉与现代医学微血管的同质性,以及现代医学缺血缺氧与中医学气血亏虚的密切联系,认为各种原因导致目中气血不足、目络亏虚失养,久之目络瘀滞,目中筋脉挛急、调节失灵,神光不能发越于远,是近视的中医病机之核心。据此,我们提出"气血不足,目络瘀滞"的近视形成假说,从气血与络脉理论角度探讨近视的病机,以期为中医药防控儿童青少年近视提供新的思路。