Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes

A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is pro-posed.The performance of the cavity is simulated and studied theoretically.Using thefinite-difference time-domain method,the parameters of the M-PCNC,including cavity thickness and width,lattice constant,and radii and numbers of holes,are optimized,with the quality factor Q and mode volume Vm as performance indicators.Mutual modulation of the lattice constant and hole radius enable the proposed M-PCNC to realize outstanding performance.The optimized cavity possesses a high quality factor Q 1.45105 and an ultra-small mode=×volume Vm 0.01(λ/n)[Zeng et al.,Opt Lett 2023:48;3981–3984]in the telecommunications wavelength range.Light can be progres-=sively squeezed in both the propagation direction and the perpendicular in-plane direction by a series of interlocked anti-slots and slots in the diamond-shaped hole structure.Thereby,the energy can be confined within a small mode volume to achieve an ultra-high Q/Vm ratio.

Small but mighty:Empowering sodium/potassium-ion battery performance with S-doped SnO_(2) quantum dots embedded in N,S codoped carbon fiber network

SnO_(2) has been extensively investigated as an anode material for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)due to its high Na/K storage capacity,high abundance,and low toxicity.However,the sluggish reaction kinetics,low electronic conductivity,and large volume changes during charge and discharge hinder the practical applications of SnO_(2)-based electrodes for SIBs and PIBs.Engineering rational structures with fast charge/ion transfer and robust stability is important to overcoming these challenges.Herein,S-doped SnO_(2)(S-SnO_(2))quantum dots(QDs)(≈3 nm)encapsulated in an N,S codoped carbon fiber networks(S-SnO_(2)-CFN)are rationally fabricated using a sequential freeze-drying,calcination,and S-doping strategy.Experimental analysis and density functional theory calculations reveal that the integration of S-SnO_(2) QDs with N,S codoped carbon fiber network remarkably decreases the adsorption energies of Na/K atoms in the interlayer of SnO_(2)-CFN,and the S doping can increase the conductivity of SnO_(2),thereby enhancing the ion transfer kinetics.The synergistic interaction between S-SnO_(2) QDs and N,S codoped carbon fiber network results in a composite with fast Na+/K+storage and extraordinary long-term cyclability.Specifically,the S-SnO_(2)-CFN delivers high rate capacities of 141.0 mAh g^(−1) at 20 A g^(−1) in SIBs and 102.8 mAh g^(−1) at 10 A g^(−1) in PIBs.Impressively,it delivers ultra-stable sodium storage up to 10,000 cycles at 5 A g^(−1) and potassium storage up to 5000 cycles at 2 A g^(−1).This study provides insights into constructing metal oxide-based carbon fiber network structures for high-performance electrochemical energy storage and conversion devices.

Neurotrophins and neural stem cells in posttraumatic brain injury repair

Traumatic brain injury(TBI)is the main cause of disability,mental health disorder,and even death,with its incidence and social costs rising steadily.Although different treatment strategies have been developed and tested to mitigate neurological decline,a definitive cure for these conditions remains elusive.Studies have revealed that vari-ous neurotrophins represented by the brain-derived neurotrophic factor are the key regulators of neuroinflammation,apoptosis,blood-brain barrier permeability,neurite regeneration,and memory function.These factors are instrumental in alleviating neu-roinflammation and promoting neuroregeneration.In addition,neural stem cells(NSC)contribute to nerve repair through inherent neuroprotective and immunomodulatory properties,the release of neurotrophins,the activation of endogenous NSCs,and in-tercellular signaling.Notably,innovative research proposals are emerging to combine BDNF and NSCs,enabling them to synergistically complement and promote each other in facilitating injury repair and improving neuron differentiation after TBI.In this review,we summarize the mechanism of neurotrophins in promoting neurogen-esis and restoring neural function after TBI,comprehensively explore the potential therapeutic effects of various neurotrophins in basic research on TBI,and investigate their interaction with NSCs.This endeavor aims to provide a valuable insight into the clinical treatment and transformation of neurotrophins in TBI,thereby promoting the progress of TBI therapeutics.

Using harmonic beam combining to generate pulse-burst in nonlinear optical laser

The ultrashort lasers working in pulse-burst mode reveal great machining performance in recent years. The number of pulses in bursts effects greatly on the removal rate and roughness. To generate a more equal amplitude of pulses in burst with linear polarization output and time gap adjustable, we propose a new method by the harmonic beam combining(HBC).The beam combining is commonly used in adding pulses into the output beam while maintaining the pulse waveform and beam quality. In the HBC, dichroic mirrors are used to combine laser pulses of fundamental wave(FW) into harmonic wave(HW), and nonlinear crystals are used to convert the FW into HW. Therefore, HBC can add arbitrarily more HW pulses to generate pulse-burst in linear polarization with simple structure. The amplitude of each pulse in bursts can be adjusted the same to increase the stability of the burst, the time gap of each pulse can be adjusted precisely by proper time delay. Because HBC adds pulses sequentially, the peak power density of the burst is the same as each pulse, pulses can be combined without concern of back-conversion which often occurs in high peak power density. In the demonstration, the extendibility of HBC was verified by combining two beams with a third beam. The combined efficiency rates were larger than 99%, and the beam quality of each beam was maintained at M^(2)≈1.4.

Therapeutic effect of Keap1-Nrf2-ARE pathway-related drugs on age-related eye diseases through anti-oxidative stress

Age-related eye diseases,including cataract,glaucoma,diabetic retinopathy(DR),and age-related macular degeneration(AMD),are the leading causes of vision loss in the world.Several studies have shown that the occurrence and development of these diseases have an important relationship with oxidative stress in the eye.The Keap1-Nrf2-ARE pathway is a classical pathway that resists oxidative stress and inflammation in the body.This pathway is also active in the development of age-related eye diseases.A variety of drugs have been shown to treat agerelated eye diseases through the Keap1-Nrf2-ARE(Kelch-like ECH-Associating protein 1-nuclear factor erythroid 2 related factor 2-antioxidant response element)pathway.This review describes the role of oxidative stress in the development of age-related eye diseases,the function and regulation of the Keap1-Nrf2-ARE pathway,and the therapeutic effects of drugs associated with this pathway on age-related eye diseases.

Clinical application of electrically evoked compound action potentials

ECAPs are the summary of multiple neurons’ spikes which could be recorded by a bidirectional stimulation-recording system via the cochlear implant,with the artifact elimination paradigms of forward-masking subtraction paradigm or alternating polarity paradigm.Three kinds of FDA approved cochlear implants support ECAP testing.This article is to summarize the clinical application of ECAP lest.ECAP test after insertion of electrode during implant operation has been widely used during cochlear implant surgery.In recent years.ECAP thresholds are also used to estimate the T levels and C levels helping programming.However,correlation between ECAP thresholds and psychophysical thresholds is affected by many factors.So far,ECAPs cannot yet be a good indicator of post-operative hearing and speech performance.

Reliability and validity of the Chinese version of the PedsQL Multidimensional Fatigue Scale in children with acute leukemia

Background:The PedsQL Multidimensional Fatigue Scale(PedsQL^(TM)MFS)is widely used to rate fatigue in children living in English-speaking countries.However,insufficient instruments are available to conduct parallel assessment on fatigue in parents and children in China.In this regard,an appropriate measurement method must be developed.Objectives:This study aims to determine the reliability and validity of the Chinese-language PedsQL^(TM)MFS.Methods:Children with cancer(n=125)and their parents were surveyed in Guangzhou,China.The parents of children aged 2e4 years completed the PedsQL^(TM)MFS proxy reports,whereas the other children and their parents completed the questionnaires by themselves.Results:The PedsQL^(TM)MFS-Chinese version demonstrated satisfactory internal consistency reliability(child self-report Cronbach's a=0.87;parent self-report Cronbach's a=0.93).The factor loadings of the items ranged from 0.78 to 0.87 for general fatigue,0.56e0.78 for sleep/rest fatigue,and 0.62e0.89 for cognitive fatigue.Conclusion:This study proves that the PedsQL^(TM)MFS-Chinese version is an effective tool for screening fatigue in Chinese children with cancer.

All-optical controlled-NOT logic gate achieving directional asymmetric transmission based on metasurface doublet

Optical logic gates play important roles in all-optical logic circuits,which lie at the heart of the next-generation optical computing technology.However,the intrinsic contradiction between compactness and robustness hinders the development in this field.Here,we propose a simple design principle that can possess multiple-input-output states according to the incident circular polarization and direction based on the metasurface doublet,which enables controlled-NOT logic gates in infrared region.Therefore,the directional asymmetric electromagnetic transmission can be achieved.As a proof of concept,a spin-dependent Janus metasurface is designed and experimentally verified that four distinct images corresponding to four input states can be captured in the far-field.In addition,since the design method is derived from geometric optics,it can be easily applied to other spectra.We believe that the proposed metasurface doublet may empower many potential applications in chiral imaging,chiroptical spectroscopy and optical computing.

Development and characteristics of a low rare-earth containing magnesium alloy with high strength-ductility synergy

In this study,we successfully developed a low RE containing Mg-3Y-2Gd-1Nd-0.5Zr(wt%)alloy with high strength-ductility synergy by combined processes of hot extrusion,hot rolling and ageing.This alloy exhibits an excellent strength-ductility balance(UTS of 345±2.0 MPa,TYS of 301±5.0 MPa and EL of 9.2±1.9%),which is better than that of many Mg-RE wrought alloys with higher RE concentration and even comparable to that of 6061 Al wrought alloy.A long-range chain-like structure consisting ofβphase,βH phase,βM phase and zig-zag atomic columns is observed for the first time in the studied alloy.The combined process of hot extrusion and hot rolling boosts the formation of deformed grains and low angle grain boundaries,and makes the deformed grains dominate in the alloy strengthening.Under this circumstance,the following ageing generates a novel heterogeneous structure comprising the long-range chain-like structure with broad interparticle spacing and the spacious precipitate-free zones in the deformed grains,which plays a key role in the concurrent strengthening and toughening of the alloy.The present study demonstrates that the deformed grains with long-range chain-like structures and precipitate-free zones is desirable microstructure for the low RE containing Mg alloys to achieve high strength-ductility synergy.

Large-Scale Energy Storage for Carbon Neutrality

The shift toward a dual-carbon strategy is expected to instigate extensive and profound changes across virtually all economic sectors and aspects of national life in China.The transformation and upgrading of energy systems and related infrastructure are particularly noteworthy.The future of energy supply will likely be dominated by renewable generation.One of the most significant challenges in this future landscape is the fluctuation and variability of wind and solar power,which often lead to a substantial amount of curtailed wind,solar,and hydropower.Such curtailment has shown an increasing trend,becoming a major obstacle to the swift deployment of renewable power generation.This challenge must be addressed to ensure the successful implementation of the dual-carbon strategy and the dominance of renewable energy in the future.

Transmission effects of high energy nanosecond lasers in laser-induced air plasma under different pressures

When a high energy nanosecond(ns)laser induces breakdown in the air,the plasma density generated in the rarefied atmosphere is much smaller than that at normal pressure.It is associated with a relatively lower absorption coefficient and reduces energy loss of the laser beam at low pressure.In this paper,the general transmission characterizations of a Joule level 10 ns 1064 nm focused laser beam are investigated both theoretically and experimentally under different pressures.The evolution of the electron density(n_(e)),the changes in electron temperature(T_(e))and the variation of laser intensity(I)are employed for numerical analyses in the simulation model.For experiments,four optical image transfer systems with focal length(f)of 200 mm are placed in a chamber and employed to focus the laser beam and produce plasmas at the focus.The results suggest that the transmittance increases obviously with the decreasing pressure and the plasma channels on the transmission path can be observed by the self-illumination.The simulation results agree well with the experimental data.The numerical model presents that the maximum n_e at the focus can reach 10^(19)cm^(-3),which is far below the critical density(n_(c)).As a result,the laser beam is not completely shielded by the plasmas.

The biosafety level-2 macromolecular crystallography beamline(BL10U2)at the Shanghai Synchrotron Radiation Facility

BL10U2 is an undulator-based macromolecular crystallography(MX)beamline located at the 3.5-GeV Shanghai Synchrotron Radiation Facility.BL10U2 is specifically designed for conducting routine and biosafety level-2(BSL-2)MX experiments utilizing high-flux tunable X-rays with energies from 7 to 18 keV,providing a beam spot size of 20μm(horizontal)×10μm(vertical)at the sample point.Certification by the Shanghai Pudong Municipal Health Commission confirmed the capability to perform BSL-2 MX experiments.The beamline is currently equipped with an Eiger X 16 M detector and two newly developed in-house high-precision diffractometers that can be switched to perform conventional or in situ crystal diffraction experiments.An automatic sample changer developed in-house allows fast sample exchange in less than 30 s,supporting high-throughput MX experimentation and rapid crystal screening.Data collection from both the diffractometer and detector was controlled by an in-house developed data collection software(Finback)with a user-friendly interface for convenient operation.This study presents a comprehensive overview of the facilities,experimental methods,and performance characteristics of the BL10U2 beamline.

Green Methanol—An Important Pathway to Realize Carbon Neutrality

1.Introduction The key to reaching China’s ambitious“dual-carbon”targets of achieving a carbon peak and carbon neutrality lies in the augmentation of renewable energy generation,particularly in the domain of solar and wind energy.In the context of China,solar energy manifests a periodic availability that is conducive to electricity generation spanning approximately 15%–20%of the annual duration,whereas wind energy exhibits an availability ranging from 20%to 25%on the basis of suitable weather.

BL02U1:the relocated macromolecular crystallography beamline at the Shanghai Synchrotron Radiation Facility

Macromolecular crystallography beamline BL17U1 at the Shanghai Synchrotron Radiation Facility has been relocated,upgraded,and given a new ID(BL02U1).It now delivers X-rays in the energy range of 6–16 keV,with a focused beam of 11.6μm×4.8μm and photon flux greater than 1012 phs/s.The high credibility and stability of the beam and good timing synchronization of the equipment significantly improve the experimental efficiency.Since June 2021,when it officially opened to users,over 4200 h of beamtime have been provided to over 200 research groups to collect data at the beamline.Its good performance and stable operation have led to the resolution of several structures based on data collected at the beamline.

The role of DNA methylation in the maintenance of phenotypic variation induced by grafting chimerism in Brassica

Grafting facilitates the interaction between heterologous cells with different genomes,resulting in abundant phenotypic variation,which provides opportunities for crop improvement.However,how grafting-induced variation occurs and is transmitted to progeny remains elusive.A graft chimera,especially a periclinal chimera,which has genetically distinct cell layers throughout the plant,is an excellent model to probe the molecular mechanisms of grafting-induced variation maintenance.Here we regenerated a plant from the T-cell layer of a periclinal chimera,TCC(where the apical meristem was artificially divided into three cell layers–from outside to inside,L1,L2,and L3;T=Tuber mustard,C=red Cabbage),named rTTT0(r=regenerated).Compared with the control(rsTTT,s=self-grafted),rTTT0 had multiple phenotypic variations,especially leaf shape variation,which could be maintained in sexual progeny.Transcriptomes were analyzed and 58 phenotypic variation-associated genes were identified.Whole-genome bisulfite sequencing analyses revealed that the methylome of rTTT0 was changed,and the CG methylation level was significantly increased by 8.74%.In rTTT0,the coding gene bodies are hypermethylated in the CG context,while their promoter regions are hypomethylated in the non-CG context.DNA methylation changes in the leaf shape variation-associated coding genes,ARF10,IAA20,ROF1,and TPR2,were maintained for five generations of rTTT0.Interestingly,grafting chimerism also affected transcription of the microRNA gene(MIR),among which the DNA methylation levels of the promoters of three MIRs associated with leaf shape variation were changed in rTTT0,and the DNA methylation modification of MIR319 was maintained to the fifth generation of selfed progeny of rTTT0(rTTT5).These findings demonstrate that DNA methylation of coding and non-coding genes plays an important role in heterologous cell interaction-induced variation formation and its transgenerational inheritance.

无阿片类药物麻醉在非插管胸腔镜手术中的应用

目的评价无阿片类药物麻醉在非插管胸腔镜手术中的安全性和可行性。方法选取2019年5月—2019年11月在胜利油田中心医院行胸腔镜下单侧肺叶切除术(肺叶、肺段楔形)患者60例作为研究对象。采用随机数字表法分为无阿片麻醉组和对照组,每组30例。无阿片麻醉组采取无阿片类药物麻醉诱导后置入喉罩保留自主呼吸,对照组行传统全身麻醉双腔气管插管。记录两组患者的麻醉满意度、手术视野暴露满意度、手术时间、苏醒时间、拔管(喉罩)时间、术毕主动下床活动时间和出院时间;记录术中及术后24 h内不良反应发生例数。结果两组的麻醉效果、手术视野暴露满意度比较,差异无统计学意义(P>0.05);两组术后苏醒时间、拔管时间、术毕下床活动时间和出院时间比较,无阿片麻醉组少于对照组(P<0.05);两组术中呛咳、低氧血症、二氧化碳蓄积发生例数比较,差异无统计学意义(P>0.05)。术中心血管不良事件无阿片麻醉组7例,对照组21例,两组比较,差异有统计学意义(P<0.05);两组术后呼吸抑制、躁动、头晕、皮肤瘙痒患者比较,无阿片麻醉组少于对照组(P<0.05);两组术后24 h内恶心、呕吐比较,差异无统计学意义(P>0.05),但术后6 h内无阿片麻醉组恶心和呕吐的发生少于对照组(P<0.05)。结论无阿片类药物麻醉应用于非插管胸腔镜手术安全可行,可减少术后不良反应,有利于患者的快速康复。

第二相对挤压态Mg-Zn-Er合金织构及力学性能的影响（英文）

研究不同的第二相对Mg-Zn-Er合金的织构及力学性能的影响。结果表明,准晶I相通过引起不连续动态再结晶机制(DDRX)而形成大量的等轴晶,进而弱化织构;而W相则通过连续动态再结晶机制(CDRX)对细化晶粒起到很重要的作用,且具有较高的织构强度。因此,含有I相的Mg-6Zn-1Er合金具有较高伸长率,为20.4%;而含有W相的Mg-2Zn-2Er合金则表现了更好的强度,其屈服强度(YS)约为247 MPa。

轧制态Mg-Zn-Er合金板材的显微组织及腐蚀行为

对轧制态Mg-x Zn-0.5Er (x=0.5, 2.0,3.0, 4.0,质量分数,%)合金的腐蚀行为和机理进行研究。结果表明,第二相与基体之间的电位差由第二相的种类和尺寸决定。Mg-0.5Zn-0.5Er合金基体中占主导地位的纳米尺寸W相引起合金局部尖锐点蚀。但是,随着粗大W相或I相体积分数的增加,腐蚀反应优先在粗大W相或I相附近发生,腐蚀更加均匀,腐蚀速率加快。长期浸泡(14 d)结果表明,合金耐蚀性由高到低的顺序为Mg-0.5Zn-0.5Er>Mg-2.0Zn-0.5Er> Mg-3.0Zn-0.5Er> Mg-4.0Zn-0.5Er。

基因修饰诱导骨髓间充质干细胞分化治疗视神经损伤

目的:探讨基因修饰诱导骨髓间充质干细胞分化治疗视神经损伤的效果。方法:将带有大鼠睫状神经营养因子(CNTF)编码序列的慢病毒转染进入从大鼠股骨中分离出的骨髓间充质干细胞。将采用钳夹视神经方法构建的视神经损伤模型大鼠随机分为对照组和研究组,分别于造模成功后第4、7、10、13d,研究组术眼玻璃体腔内注入经转染的骨髓间充质干细胞悬浮液,对照组术眼玻璃体腔注入等量生理盐水。造模成功后第14d,观察两组大鼠的光反射情况,视网膜神经节细胞数量及胶质原纤维酸性蛋白(GFAP)和Caspase-3蛋白表达水平。结果:研究组大鼠光反射恢复率明显高于对照组(83%vs25%,P<0.05),视网膜细胞结构相对整齐,可见少量空泡,而对照组大鼠视网膜细胞结构欠整齐,可见明显空泡,视网膜神经节细胞数明显减少,且对照组大鼠视网膜GFAP和Caspase-3蛋白表达水平均高于研究组。结论:基因修饰诱导骨髓间充质干细胞分化能够有效治疗大鼠视神经损伤。

CCK-8法检测蓝光和白光对ARPE-19细胞增殖的影响

目的:探讨蓝光和白光分别光照不同时间对人视网膜色素上皮(ARPE-19)细胞增殖的影响,为进一步检测光照损伤过程中相关因子的变化情况,研究光照损伤过程中的信号转导机制奠定基础。方法:收集生长状态良好的ARPE-19细胞进行实验,制作CCK-8标准曲线,确定实验合适的ARPE-19细胞密度及CCK-8试剂的反应时间。将细胞分为避光组、蓝光组、白光组,分别光照3、6、9h,再避光培养12h后采用CCK-8法检测不同光源光照不同时间对ARPE-19细胞增殖率的影响。结果:通过CCK-8标准曲线选择每孔细胞数量为20000个,CCK-8溶液作用4h后测量相应吸光度值。CCK-8检测结果示,避光组、蓝光组、白光组三组细胞光照不同时间细胞增殖率比较,差异有统计学意义(P<0.01)。蓝光组细胞光照3、6、9h,各时间点细胞增殖率比较,差异有统计学意义(P<0.001),且随着光照时间的延长,细胞增殖率逐渐降低。白光组细胞光照3、6、9h,各时间点细胞增殖率比较,差异有统计学意义(P<0.05),其中光照3h和6h细胞增殖率比较,差异有统计学意义(P<0.05),而光照9h分别与光照3、6h细胞增殖率比较,差异均无统计学意义(P=0.253、0.120)。白光光照3～6h细胞增殖率呈下降趋势,而光照6～9h细胞增殖率呈现上升趋势。相同光照时间,蓝光组和白光组细胞增殖率均低于避光组,且蓝光组细胞增殖率均低于白光组,差异均有统计学意义(P<0.05)。结论:光照能抑制ARPE-19细胞的增殖,其中蓝光光照细胞增殖率明显低于白光,且随光照时间的增长,细胞增殖率进一步降低。