Linear dichroism transition and polarization-sensitive photodetector of quasi-one-dimensional palladium bromide

Perpendicular optical reversal of the linear dichroism transition has promising applications in polarization-sensitive optoelectronic devices. We perform a systematical study on the in-plane optical anisotropy of quasi-one-dimensional PdBr_(2) by using combined measurements of the angle-resolved polarized Raman spectroscopy(ARPRS) and anisotropic optical absorption spectrum. The analyses of ARPRS data validate the anisotropic Raman properties of the PdBr_(2) flake.And anisotropic optical absorption spectrum of PdBr_(2) nanoflake demonstrates distinct optical linear dichroism reversal. Photodetector constructed by PdBr_(2) nanowire exhibits high responsivity of 747 A·W^(-1) and specific detectivity of 5.8×10^(12) Jones. And the photodetector demonstrates prominent polarization-sensitive photoresponsivity under 405-nm light irradiation with large photocurrent anisotropy ratio of 1.56, which is superior to those of most of previously reported quasi-one-dimensional counterparts. Our study offers fundamental insights into the strong optical anisotropy exhibited by PdBr_(2), establishing it as a promising candidate for miniaturization and integration trends of polarization-related applications.

Enhanced conductivity and weakened magnetism in Pb-doped Sr_(2)IrO_(4)

Group IV element Pb has been selected as the dopant to dope at the Sr site of Sr_(2)IrO_(4). It is exciting to find that the single-phase crystal structure could be maintained with a high Pb doping level of up to x=0.3 in Sr_(2-x)Pb_(x)IrO_(4). The mapping data obtained from energy-dispersive x-ray spectroscopy analyses give solid evidence that the Pb ions are uniformly distributed in the Sr_(2)IrO_(4) matrix. The incorporation of Pb leads to a moderate depression of the canted antiferromagnetic ordering state. The electrical conductivity could be greatly enhanced when the Pb doping content is higher than x=0.2.The present results give a fresh material base to explore new physics in doped Sr_(2)IrO_(4) systems.

The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

Boosting Chemodynamic Therapy by the Synergistic Effect of Co‑Catalyze and Photothermal Effect Triggered by the Second Near‑Infrared Light

In spite of the tumor microenvironments responsive cancer therapy based on Fenton reaction(i.e.,chemodynamic therapy,CDT)has been attracted more attentions in recent years,the limited Fenton reaction efficiency is the important obstacle to further application in clinic.Herein,we synthesized novel FeO/MoS2 nanocomposites modified by bovine serum albumin(FeO/MoS2-BSA)with boosted Fenton reaction efficiency by the synergistic effect of co-catalyze and photothermal effect of MoS2 nanosheets triggered by the second near-infrared(NIR II)light.In the tumor microenvironments,the MoS2 nanosheets not only can accelerate the conversion of Fe3+ions to Fe2+ions by Mo4+ions on their surface to improve Fenton reaction efficiency,but also endow FeO/MoS2-BSA with good photothermal performances for photothermal-enhanced CDT and photothermal therapy(PTT).Consequently,benefiting from the synergetic-enhanced CDT/PTT,the tumors are eradicated completely in vivo.This work provides innovative synergistic strategy for constructing nanocomposites for highly efficient CDT.

Research progress on the role of connective tissue growth factor in fibrosis of diabetic retinopathy

Diabetic retinopathy（DR） is one of the most important types of diabetic microangiopathy, which is a specific change of fundus lesions and is one of the most serious complications of diabetes. When DR develops to proliferative DR, the main factors of decreasing vision, and even blindness, include retinal detachment and vitreous hemorrhage caused by contraction of blood vessels by fiber membrane. Recent studies reported that the formation of fiber vascular membrane is closely related to retinal fibrosis. The connective tissue growth factor（CTGF） is a cytokine that is closely related to DR fibrosis. However, its mechanism is poorly understood. This paper summarizes the recent studies about CTGF on DR fibrosis for a comprehensive understanding of the role and mechanism of CTGF in PDR.

Refractive outcomes after vitrectomy combined with phacoemulsification of idiopathic macular holes

AIM:To report the refractive outcomes after vitrectomy combined with phacoemulsification and intraocular lens(IOL)implantation(phaco-vitrectomy)in idiopathic macular holes(IMH).METHODS:A total of 56 eyes with IMH(IMH group)that underwent phaco-vitrectomy and 44 eyes with age-related cataract(ARC group)that underwent cataract surgery were retrospectively reviewed.The best corrective visual acuity(BCVA),predicted refractive error(PRE),actual refractive error(ARE),axial length(AL),were measured in both groups before and 6 mo after operation.The power calculation of IOL and the predicted refractive error(PRE)were calculated according to the SRK/T formula.The difference of PRE and ARE between the two groups were compared and analyzed.RESULTS:In the IMH group,the diameters of macular holes were 271.73±75.85μm,the closure rate was 100%.The pre-and post-operative BCVA were 0.80±0.35 and 0.40±0.35 log MAR.The PRE of A-ultrasound and IOL Master in the IMH group was-0.27±0.25 and 0.10±0.66 D.The postoperative mean absolute prediction error(MAE)was observed to be 0.58±0.65 and 0.53±0.37 D in the IOL Master and A-ultrasound(P=0.758).The PRE and ARE of the IMH group were 0.10±0.66 D and-0.19±0.64 D(P=0.102).The PRE and ARE of the ARC group was-0.43±0.95 and-0.31±0.93 D(P=0.383).The difference between PRE and ARE was-0.33±0.81 and 0.09±0.64 D in the IMH and ARC groups(P=0.021).The proportion of myopic shift was 67.9%in the IMH group and 27.3%in the ARC group(P=0.004).CONCLUSION:The myopic shift can be observed in patients with IMH after phaco-vitrectomy.

Incomplete fluid-air exchange technique for idiopathic macular hole surgery

AIM: To explore an improved procedure involving incomplete fluid-air exchange for idiopathic macular hole(IMH), and the closure rate, visual function, and the visual field of macular holes(MHs) were evaluated.METHODS: This prospective randomized controlled study, included 40 eyes of 40 patients with IMH who were treated with pars plana vitrectomy and peeling of the internal limiting membrane. They were grouped by random digital table. Twenty-one eyes underwent incomplete fluidair exchange(IFA) and 19 eyes underwent traditional complete fluid-air exchange(CFA) as the control group. Outcomes included best-corrected visual acuity(BCVA), intraocular pressure, and optical coherence tomography, light adaptive electroretinography, and visual field evaluations.RESULTS: All MHs <400 μm were successfully closed. BCVAs before and 6 mo after surgery were 0.82±0.41 logMAR and 0.28±0.17 logMAR in IFA group and 0.86±0.34 logMAR and 0.34±0.23 logMAR in CFA group, respectively. The electroretinogram analysis of patients in IFA group revealed increases in b-wave amplitudes at 1, 3, and 6 mo after surgery. Additionally, patients in IFA group showed an amplitude increase of 28.6% from baseline at 6 mo(P<0.05), while no obvious improvements were noted in CFA group. Although there were no statistically significant improvements in either group, the IFA group showed a slight increase in mean sensitivity(P>0.05).CONCLUSION: IFA is a reliable method that offers comparable closure rate to CFA and facilitates improvements in visual function.

不同填充物联合玻璃体切除及内界膜剥除治疗特发性黄斑裂孔疗效比较

目的:探讨不同填充物联合玻璃体切除及内界膜剥除治疗特发性黄斑裂孔(IMH)的疗效及安全性。方法:回顾性研究。选择2018-07/2020-03本院眼科收治的IMH患者117例117眼作为研究对象,两组患者均行玻璃体切除联合内界膜剥除术,根据术中填充材料不同分为两组:采用空气填充者65眼;采用C_(3)F_(8)填充者52眼。于术前及术后1、2、3mo时进行复查,统计患者末次随访时裂孔闭合率、闭合形态、最佳矫正视力(BCVA)、黄斑中央视网膜厚度(CRT)、外界膜层(ELM)缺损直径、椭圆体带缺损直径、眼压、术后并发症发生情况。结果:空气填充组、C_(3)F_(8)填充组患者术后气体吸收时间分别为8.55±2.17、25.74±7.41d(P<0.05);空气填充组及C_(3)F_(8)填充组黄斑裂孔闭合率(95.4%vs 98.1%)和闭合孔形态比例比较均无差异(P>0.05)。两组患者术后3mo时BCVA和CRT较术前有差异(P<0.001),ELM缺损直径、椭圆体带缺损直径较术前降低(P<0.001),两组间BCVA、CRT、ELM缺损直径、椭圆体带缺损直径比较均无差异(P>0.05)。两组患者治疗前后眼压比较无差异(P>0.05),两组患者均未发生严重并发症。结论:玻璃体切除及内界膜剥除联合空气填充及C_(3)F_(8)填充治疗IMH疗效及安全性相当,临床可根据实际情况选择。

Narrow-band high-transmittance birefringent filter and its application in wide color gamut display

We propose a narrow-band birefringent filter and its application in wide color gamut.The birefringent filter consists of five phase retarders and two polarizers,and it has both narrow band and high transmittance.In the experiment,we fabricate the birefringent filter using quartz phase retarders and polarizers,and apply it in serval different displays.The color gamuts of displays are enhanced more than 30%NTSC(National Television System Committee),and the widest color gamuts that have been obtained are 126%NTSC in liquid crystal displays and 138%NTSC in organic light-emitting devices.Moreover,the deep blue light in spectrum of display can be reduced using the birefringent filter.The birefringent filter can be an efficient element to achieve wide color gamut display.

Simulation Analysis of Ammonia Leakage and Dispersion in a Large-Scale Refrigeration System

The use of ammonia in large-scale refrigeration systems(such as those used for a stadium)requires adequate ammonia leakage prevention mechanisms are put in place.In the present study,numerical simulations have been conducted to study the dispersion law in the ammonia machinery room of the refrigeration system for the 2022 Beijing Winter Olympics.The wind speed,and release location have been varied to investigate their effects on the dispersion profile.Different positions of the leakage points in the ammonia storage tank have been found to lead to different areas affected accordingly.In general,the dangerous region area decreases with an increase in the wind speed.However,when the wind is aligned with the leakage direction,this trend is reverted.The study may offer an effective method to predict the impact of ammonia dispersion and implement the safe operation of such large-scale systems.

螺杆空压机用多翼离心风机气动性能改进

为研究多翼离心风机原型机出口风速均匀性差机理,采用CFD数值模拟技术,计算风机内部气动性能及出口风速分布规律,并通过实验验证了计算模型和计算方法的准确性。计算结果显示该风机存在内部流场紊乱、叶道内涡旋多且蜗舌处回流严重等问题,最终造成风机出口均匀性差。在保证安装接口一致的前提下,通过优化风机进口集流器、叶片结构、叶片数量、蜗壳型线及扩压器等参数,改善了进气流道以及风扇与蜗壳匹配性,有效提升风机内部气动性能,消除涡流和回流现象。同时在扩压器进气口处增加整流破涡设计,进一步改善风机出口均匀性。实验结果表明:风机出口风速差值由10m/s降低至3m/s。

Oxidative damage of chronic PM2.5 exposure to rat lung tissue

Objective:To investigate the oxidative damage caused by chronic exposure to PM2.5 in rat lung tissues according to the PM2.5 concentration in the atmospheric environment.Methods:Forty healthy SD rats were randomly divided into 4 groups,the control group and the 5 mg/kg,10 mg/kg,20 mg/kg PM2.5 exposure groups.The rats in each group were administered by intratracheal instillation with 1ml/kg,2 times per week.After 8 weeks of exposure,the changes of lung histopathology,superoxide dismutase(SOD),malondialdehyde(MDA),catalase(CAT)and reduced glutathione/oxidized glutathione(GSH/GSSG)were detected.Results:Compared with the control group,the histopathological changes in the lung tissue of the three dose groups exposed to PM2.5 were significant.Masson staining showed obvious collagen fibrosis.The activities of SOD and CAT in the lung tissue of the exposed group were decreased,and the contents of MDA were increased with statistically significant(P<0.05),showing that the difference was the most obvious in the middle-dose group.The GSH/GSSG ratio in the lung tissue decreased,indicating that the degree of oxidative damage was aggravated.Conclusion:Chronic exposure to PM2.5 could induce oxidative stress in the lung tissue of rats and caused different degrees of oxidative damage.

Atom-referenced and stabilized soliton microcomb

For the applications of the frequency comb in microresonators,it is essential to obtain a fully frequency-stabilized microcomb laser source.In this study,we present a system for generating a fully atom-referenced stabilized soliton microcomb.The pump light around 1560.48 nm is locked to an ultra-low-expansion(ULE)cavity.This pump light is then frequency-doubled and referenced to the atomic transition of87Rb.The repetition rate of the soliton microcomb is injection-locked to an atomic-clockstabilized radio frequency(RF)source,leading to mHz stabilization at 1 s.As a result,all comb lines have been frequencystabilized based on the atomic reference and the ULE cavity,achieving a very high precision of approximately 18 Hz at 1 s,corresponding to the frequency stability of 9.5×10^(-14).Our approach provides a fully stabilized microcomb experiment scheme with no requirement of f-2f technique,which could be easily implemented and generalized to various photonic platforms,thus paving the way towards the ultraprecise optical sources for high precision spectroscopy.

Multi-layered roles of BBX proteins in plant growth and development

Light and phytohormone are external and internal cues that regulate plant growth and development throughout their life cycle.BBXs(B-box domain proteins)are a group of zinc finger proteins that not only directly govern the transcription of target genes but also associate with other factors to create a meticulous regulatory network to precisely regulate numerous aspects of growth and developmental processes in plants.Recent studies demonstrate that BBXs play pivotal roles in light-controlled plant growth and development.Besides,BBXs have been documented to regulate phytohormone-mediated physiological procedures.In this review,we summarize and highlight the multi-faced role of BBXs,with a focus in photomorphogenesis,photoperiodic flowering,shade avoidance,abiotic stress,and phytohormone-mediated growth and development in plant.

一种兼具程序性缓释双氢青蒿素和Fe^(2+)自供应能力的智能纳米药物用于肿瘤协同治疗

双氢青蒿素(DHA)作为一种新型的抗癌药物引起了全世界的广泛关注.然而,DHA的固有缺陷降低了其在血液系统中的运输效率,而肿瘤细胞中铁含量不足进一步导致疗效不佳.因此,构建一个可同时负载DHA和Fe^(3+)并在肿瘤微环境中特异性释放出DHA/Fe的纳米药物具有重大意义.本文报道了一种智能纳米药物CaCO_(3)@DHA@Fe^(3+)-TA@PEG(CDFP NPs)用于肿瘤协同治疗.Fe^(3+)-TA壳层的包覆赋予CDFP NPs良好的光热性能.此外,CDFP NPs在酸性的肿瘤微环境中可以快速降解并释放出TA,Fe^(3+),DHA和Ca^(2+).Fe^(3+)与TA反应生成Fe^(2+),Fe^(2+)与DHA相互作用生成高毒性的自由基.此外,在氧化应激状态下,Ca^(2+)过载导致线粒体功能紊乱,最终诱导肿瘤细胞死亡.在光热治疗,活性氧,Ca^(2+)过载的协同作用下,CDFP NPs在体内外均表现出良好的治疗效果.

Involvements of chloride ion in decolorization of Acid Orange 7 by activated peroxydisulfate or peroxymonosulfate oxidation

The effects of chloride anion （Cl-） （up to 1.0 mol/L） on the decolorization of a model compound,azo dye Acid Orange 7 （AO7）,by sulfate radical （SO4-） based-peroxydisulfate （PS） or peroxymonosulfate （PMS） oxidation under various activated conditions （UV 254 nm /PS,Thermal （70°C/PS,UV 254 nm /PMS,Co 2＋ /PMS） were investigated.Methanol and NH4 ＋ were used as quenching reagents to determine the contributions of active chlorine species （dichloride radical （Cl2-.） and hypochlorous acid （HClO））.The results indicated that the effects of Cl- on the reaction mechanism were different under various activated conditions.For UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl- concentration increased,probably due to the reaction between Cl- and SO4-.and the generation of Cl2-.or HClO.For UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/L.As Cl- concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with Cl- to form HClO.For Co2＋ /PMS,Cl- exhibited a significant inhibiting effect even at low concentration （ 0.01 mol/L）.When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co 2＋ was almost completely inhibited.Under this condition,HClO maybe played a major role in decolorization of AO7.The results implicated that chloride ion is an important factor in SO4-.-based degradation of organic contamination in chloride-containing water.

Frequency stabilization and tuning of breathing solitons in Si3N4 microresonators

Dissipative Kerr solitons offer broadband coherent and low-noise frequency combs and stable temporal pulse trains,having shown great potential applications in spectroscopy,communications,and metrology.Breathing solitons are a particular kind of dissipative Kerr soliton in which the pulse duration and peak intensity show periodic oscillation.Here we have investigated the breathing dissipative Kerr solitons in silicon nitride(Si3N4)microrings,while the breathing period shows uncertainties of around megahertz(MHz)order in both simulation and experiments.This instability is the main obstacle for future applications.By applying a modulated signal to the pump laser,the breathing frequency can be injection locked to the modulation frequency and tuned over tens of MHz with frequency noise significantly suppressed.Our demonstration offers an alternative knob for the control of soliton dynamics in microresonators and paves a new avenue towards practical applications of breathing solitons.

Fabrication of the high-Q Si_(3)N_(4) microresonators for soliton microcombs

The microresonator-based soliton microcomb has shown a promising future in many applications.In this work,we report the fabrication of high quality[Q]Si_(3)N_(4)microring resonators for soliton microcomb generation.By developing the fabri-cation process with crack isolation trenches and annealing,we can deposit thick stoichiometric Si3N4 film of 800 nm without cracks in the central area.The highest intrinsic Q of the Si_(3)N_(4)microring obtained in our experiments is about 6×10^(6),corresponding to a propagation loss as low as 0.058 dBm/cm.With such a high Q film,we fabricate microrings with the anomalous dispersion and demonstrate the generation of soliton microcombs with 100 mW on-chip pump power,with an optical parametric oscillation threshold of only 13.4 mW.Our Si_(3)N_(4)integrated chip provides an ideal platform for researches and applications of nonlinear photonics and integrated photonics.

Spectrally multiplexed and bright entangled photon pairs in a lithium niobate microresonator

On-chip bright quantum sources with multiplexing ability are extremely high in demand for integrated quantum networks with unprecedented scalability and complexity.Here,we demonstrate a bright and broadband biphoton quantum source with spectral multiplexing generated in a lithium niobate microresonator system.Without introducing the conventional domain poling,the on-chip microdisk produces photon pairs covering a broad bandwidth promised by natural phase matching in spontaneous parametric down conversion.Experimentally,the multiplexed photon pairs are characterized by 30 nm bandwidth limited by the filtering system,providing over 40 multiplexing channels with a 0.8 nm channel spacing.Meanwhile,the generation rate reaches 5.13 MHz/μW with a coincidence-to-accidental ratio up to 804,and the quantum source manifests a high purity with a heralded single photon correlation g^((2))_(H)(0)=0.0098±0.0021.Furthermore,the energy-time entanglement is demonstrated with an excellent interference visibility of 96.5%±2%.Such a quantum source at the telecommunication band paves the way for high-dimensional entanglement and future integrated quantum information systems.

Soliton formation and spectral translation into visible on CMOS-compatible 4H-silicon-carbide-oninsulator platform

Recent advancements in integrated soliton microcombs open the route to a wide range of chip-based communication,sensing,and metrology applications.The technology translation from laboratory demonstrations to real-world applications requires the fabrication process of photonics chips to be fully CMOS-compatible,such that the manufacturing can take advantage of the ongoing evolution of semiconductor technology at reduced cost and with high volume.Silicon nitride has become the leading CMOS platform for integrated soliton devices,however,it is an insulator and lacks intrinsic second-order nonlinearity for electro-optic modulation.Other materials have emerged such as AlN,LiNbO_(3),AlGaAs and GaP that exhibit simultaneous second-and third-order nonlinearities.Here,we show that silicon carbide(SiC)--already commercially deployed in nearly ubiquitous electrical power devices such as RF electronics,MOSFET,and MEMS due to its wide bandgap properties,excellent mechanical properties,piezoelectricity and chemical inertia--is a new competitive CMOS-compatible platform for nonlinear photonics.High-quality-factor microresonators(Q=4×10^(6))are fabricated on 4H-SiC-on-insulator thin films,where a single soliton microcomb is generated.In addition,we observe wide spectral translation of chaotic microcombs from near-infrared to visible due to the second-order nonlinearity of SiC.Our work highlights the prospects of SiC for future low-loss integrated nonlinear and quantum photonics that could harness electro-opto-mechanical interactions on a monolithic platform.