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Influence of Nd^(3+) concentration on mid-infrared emission in PbF_(2) crystal co-doped with Ho^(3+) and Nd^(3+) ions

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Journal of Rare Earths 2024年第3期42卷 479-487,I0002页

作者： Yan Chen Juncheng Tan Peixiong Zhang Weibi Zheng Lin Li Lianhan Zhang Zhen Li Yin Hang Zhenqiang Chen department of Optoelectronic Engineering Jinan UniversityGuangzhou510632China Guangdong Provincial Engineering Research Centerof Crystal and laser Technology.Guangzhou 510632China Research Center of laser Crystal Key Laboratory of High Power Laser MaterialsShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai201800China

A promising series of Ho_(y)Nd_(x)Pb_((1-x-y))F_2(x = 0, 0.01, 0.02, 0.03, 0.04;y = 0.02) crystals was grown by the Bridgman method. The influence of the Nd^(3+)ions concentration on mid-infrared(~2.0, ~2.9 and ~3.9 μm)fluorescence emissions of Ho^(3+)ions in the PbF_(2) crystal excited by 808 nm laser diode was investigated in this work. The energy transfer mechanism between Nd^(3+)ions and Ho~(3+)ions under different concentrations of the Nd^(3+)ions was systematically analyzed. The results show that the Nd^(3+)ions have good sensitization and deactivation effect on the Ho^(3+)ions to stimulate the mid-infrared fluorescence emissions. The experimental analysis proves that the sensitization efficiency of the Nd^(3+)ions is relatively stable at around 93.45% with varying Nd^(3+)-doping concentrations. Concentration dependence studies indicate that the concentration of the Nd^(3+)ions has significant influence on mid-infrared *** the doping concentration of the Nd^(3+)ions is up to 2.0 at%, the intensity of ~2.0, ~2.9 and ~3.9 μm emissions all reach the maximum. The output characteristics of a 3.9 μm laser are simulated, and it is found that with the increase of the Nd^(3+)-doping concentration, the peak power, pulse width, and peak energy all meet the trend of first increasing and then decreasing, and Ho_(0.02)Nd_(0.02)Pb_(0.96)F_(2) crystal displays the best performance. All the results show that the Nd^(3+)/Ho^(3+)co-doped PbF_(2) crystals might act as a useful optical medium for mid-infrared laser applications.

关键词： Crystal growth Mid-infrared PbF_(2) Rare earth ions

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Quantitative analysis of laser-generated ultrasonic wave characteristics and their correlation with grain size in polycrystalline materials

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Chinese Physics B 2024年第8期33卷 526-543页

作者：徐兆文白雪马健万壮壮王超群 laser Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250104China

Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was *** high energy of the pulsed laser with a large irradiation spot simultaneously generated ultrasonic longitudinal and shear waves at the epicenter under the slight ablation *** optimized denoising technique based on wavelet thresholding and variational mode decomposition was applied to reduce noise in shear waves with a low signal-to-noise *** approach for characterizing grain size was proposed using spectral central frequency ratio(SCFR)based on time-frequency *** results demonstrate that the generation regime of ultrasonic waves is not solely determined by the laser power density;even at high power densities,a high energy with a large spot can generate an ultrasonic waveform dominated by the thermoelastic *** is ascribed to the intensification of the thermoelastic effect with the proportional increase in laser irradiation spot area for a given laser power ***,both longitudinal and shear wave SCFRs are linearly related to grain size in polycrystalline materials;however,the shear wave SCFR is more sensitive to finer-grained *** study holds great significance for evaluating metal material properties using laser ultrasound.

关键词： laser-ultrasonics polycrystalline materials ultrasonic time-frequency characteristics grain size

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Decoupling of temporal/spatial broadening effects in Doppler wind LiDAR by 2D spectral analysis

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Chinese Physics B 2024年第3期33卷 447-452页

作者：刘珍张云鹏竹孝鹏刘继桥毕德仓陈卫标 Space laser Engineering department Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady ***,the measured spectral data are analyzed in the time dimension and frequency dimension to cope with the temporal wind shear and achieve the optimal accumulation time.A hardware-efficient algorithm combining the interpolation and cross-correlation is used to enhance the wind retrieval accuracy by reducing the frequency sampling interval and then reduce the spectral width calculation ***,the temporal broadening effect and spatial broadening effect are decoupled according to the strategy we developed.

关键词： Doppler wind LiDAR spectral analysis hardware efficiency spectrum broadening effects

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Design consideration of phthalocyanines as sensitizers for enhanced sono-photodynamic combinatorial therapy of cancer

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1077-1097页

作者： Lindokuhle Cindy Nene Heidi Abrahamse laser Research Centre Faculty of Health SciencesUniversity of JohannesburgDoornfontein 2028South Africa

Cancer remains one of the diseases with the highest incidence and mortality *** treatment modalities have demonstrated threatening drawbacks including invasiveness,noncontrollability,and development of resistance for some,including chemotherapy,radiation,and ***-photodynamic combinatorial therapy(SPDT)has been developed as an alternative treatment modality which offers a non-invasive and controllable therapeutic *** combines the mechanism of action of sonodynamic therapy(SDT),which uses ultrasound,and photodynamic therapy(PDT),which uses light,to activate a sensitizer and initiate cancer *** use of phthalocyanines(Pcs)as sensitizers for SPDT is gaining interest owing to their ability to induce intracellular oxidative stress and initiate toxicity under SDT and *** review discusses some of the structural prerequisites of Pcs which may influence their overall SPDT activities in cancer therapy.

关键词： Sonodynamic therapy Photodynamic therapy Combinatorial therapy Phthalocyanines Sensitizer Cancer

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Physics package based on intracavity laser cooling ^(87)Rb atoms for space cold atom microwave clock

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Chinese Physics B 2024年第7期33卷 22-26页

作者：邓思敏达任伟项静峰赵剑波李琳张迪万金银孟艳玲蒋小军李唐刘亮吕德胜 Aerospace laser Technology and System department Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Mechanics Chinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

This article proposes a new physics package to enhance the frequency stability of the space cold atom clock with the advantages of a microgravity environment. Clock working processes, including atom cooling, atomic state preparation,microwave interrogation, and transition probability detection, are integrated into the cylindrical microwave cavity to achieve a high-performance and compact physics package for the space cold atom clock. We present the detailed design and ground-test results of the cold atom clock physics package in this article, which demonstrates a frequency stability of 1.2×10^(-􀀀12) τ^(-1/2) with a Ramsey linewidth of 12.5 Hz, and a better performance is predicted with a 1 Hz or a narrower Ramsey linewidth in microgravity environment. The miniaturized cold atom clock based on intracavity cooling has great potential for achieving space high-precision time-frequency reference in the future.

关键词： atomic clock microgravity microwave cavity space station frequency stability

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Salicylic acid positively regulates maize defenses against lepidopteran insects

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Plant Diversity 2024年第4期46卷 519-529页

作者： Yohannes Besufekad Setotaw Jing Li Jinfeng Qi Canrong Ma Mou Zhang Cuilian Huang Lei Wang Jianqiang Wu department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China CAS Center for Excellence in Biotic interactions University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Plant Diversity and Specialty Crops Beijing 100093China

In response to insect attack,plants use intricate signaling pathways,including phytohormones,such as jasmonate(JA),ethylene(ET),and salicylic acid(SA),to activate ***(Zea mays)is one of the most important staple food crops around the *** studies have shown that the JA and ET signaling play important roles in maize defense against insects,but little is known about whether and how SA regulates maize resistance to insect *** this study,we ectopically expressed the NahG(salicylate hydroxylase)gene in maize plants(NahG maize)to block the accumulation of *** was found that compared with the wild-type(WT)maize,the NahG-maize exhibited decreased resistance to the generalist insects Spodoptera litura and Spodoptera frugiperda and the specialist Mythimna separata,and the compromised resistance in the NahG maize was associated with decreased levels of defensive metabolites benzoxazinoids(Bxs)and chlorogenic acid(CA).Quantification of simulated *** feedinginduced JA,JA-isoleucine conjugate(JA-Ile),and ET in the WT and NahG maize indicated that SA does not regulate JA or JA-Ile,but positively controls *** provide evidence suggesting that the SA pathway does not crosstalk with the JA or the ET signaling in regulating the accumulation of Bxs and *** analysis revealed that the bHLH,ERF,and WRKY transcription factors might be involved in SAregulated *** study uncovers a novel and important phytohormone pathway in maize defense against lepidopterous larvae.

关键词： Benzoxazinoids Salicylic acid Herbivory Maize Transcriptome

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On-chip ultrafast stackable dielectric laser positron accelerator

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Chinese Physics B 2024年第3期33卷 350-354页

作者：孙斌何阳帆潘晨浩樊思劼王度王少义赵宗清 department of Plasma Physics and Fusion Engineering School of Nuclear Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026China National Key Laboratory of Plasma Physics Research Center of Laser FusionChina Academy of Engineering PhysicsMianyang 621900China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of High Field laser Physics and Chinese Academy of sciences Center for Excellence in Ultra-Intense laser Science Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China department of Engineering Physics Tsinghua UniversityBeijing 100084China The Institute of Technological sciences Wuhan UniversityWuhan 430072China

We present a first on-chip positron accelerator based on dielectric laser *** innovative approach significantly reduces the physical dimensions of the positron acceleration apparatus,enhancing its feasibility for diverse *** utilizing a stacked acceleration structure and far-infrared laser technology,we are able to achieve a seven-stage acceleration structure that surpasses the distance and energy gain of using the previous dielectric laser acceleration ***,we are able to compress the positron beam to an ultrafast sub-femtosecond scale during the acceleration process,compared with the traditional methods,the positron beam is compressed to a greater *** also demonstrate the robustness of the stacked acceleration structure through the successful acceleration of the positron beam.

关键词： dielectric laser accelerator positron accelerator high gradient accelerator inverse Cherenkov effect

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Large-scale interplant exchange of macromolecules between soybean and dodder under nutrient stresses

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Plant Diversity 2024年第1期46卷 116-125页

作者： Jingxiong Zhang Shalan Li Wenxing Li Zerui Feng Shuhan Zhang Xijie Zheng Yuxing Xu Guojing Shen Man Zhao Guoyan Cao Xuna Wu Jianqiang Wu department of Economic Plants and Biotechnology Yunnan Key Laboratory for Wild Plant ResourcesKunming Institute of BotanyChinese Academy of SciencesKunming 650201China CAS Center for Excellence in Biotic interactions University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Conservation and Utilization of Bio-Resources in Yunnan and Center for Life Science School of Life SciencesYunnan UniversityKunming 650500China

Parasitic plants and their hosts communicate through haustorial *** deficiency is a common stress for plants,yet little is known about whether and how host plants and parasites communicate during adaptation to such nutrient *** this study,we used transcriptomics and proteomics to analyze how soybean(Glycine max)and its parasitizing dodder(Cuscuta australis)respond to nitrate and phosphate deficiency(-N and-P).After-N and-P treatment,the soybean and dodder plants exhibited substantial changes of transcriptome and proteome,although soybean plants showed very few transcriptional responses to-P and dodder did not show any transcriptional changes to either-N ***,large-scale interplant transport of mRNAs and proteins was *** the mobile mRNAs only comprised at most 0.2%of the transcriptomes,the foreign mobile proteins could reach 6.8%of the total proteins,suggesting that proteins may be the major forms of interplant ***,the interplant mobility of macromolecules was specifically affected by the nutrient regimes and the transport of these macromolecules was very likely independently *** study provides new insight into the communication between host plants and parasites under stress conditions.

关键词： Cuscuta Mobile molecules Nutrient deficiency Host plant-parasitic plant interaction Interplant transport Systemic signaling

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HvMPK4 phosphorylates HvWRKY1 to enhance its suppression of barley immunity to powdery mildew fungus

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Journal of Genetics and Genomics 2024年第3期51卷 313-325页

作者： Pengya Xue Ling Zhang Renchun Fan Yanan Li Xinyun Han Ting Qi Lifang Zhao Deshui Yu Qian-Hua Shen State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic interactions College of Advanced Agricultural SciencesUniversity of Chinese Academy of SciencesBeijing 100049China department of Nutritional sciences&Toxicology University of CaliforniaBerkeleyCA 94720USA Lushan Botanical Garden Chinese Academy of ScienceJiujiangJiangxi 332900China

Mitogen-activated protein kinase(MAPK)cascades play important roles in disease resistance in model plant ***,the functions of MAPK signaling pathways in crop disease resistance are largely *** we report the function of HvMKK1-HvMPK4-HvWRKY1 module in barley immune ***4 is identified to play a negative role in barley immune response against Bgh,as virus-induced gene silencing of HvMPK4 results in enhanced disease resistance whilst stably overexpressing HvMPK4 leads to super-susceptibility to Bgh ***,the barley MAPK kinase HvMKK1 is found to specifically interact with HvMPK4,and the activated HvMKK1^(DD) variant specifically phosphorylates HvMPK4 in ***,the transcription factor HvWRKY1 is identified to be a downstream target of HvMPK4 and phosphorylated by HvMPK4 in vitro in the presence of HvMKK1^(DD).Phosphorylation assay coupled with mutagenesis analyses identifies S122,T284,and S347 in HvWRKY1 as the major residues phosphorylated by ***1 is phosphorylated in barley at the early stages of Bgh infection,which enhances its suppression on barley immunity likely due to enhanced DNA-binding and transcriptional repression *** data suggest that the HvMKK1-HvMPK4 kinase pair acts upstream of HvWRKY1 to negatively regulate barley immunity against powdery mildew.

关键词： Barley MPK4 WRKY1 Phosphorylation Disease resistance Powdery mildew

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Design of an on‑chip wavelength conversion device assisted by an erbium‑ytterbium co‑doped waveguide amplifier

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Frontiers of Optoelectronics 2024年第2期17卷 51-60页

作者： Chen Zhou Xiwen He Mingyue Xiao Deyue Ma Weibiao Chen Zhiping Zhou School of Physical sciences University of Science and Technology of ChinaHefei 230026China Aerospace laser Technology and System department Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Hangzhou Aijie Optoelectronic Technology Co.Ltd. Hangzhou 311400China

In current documented studies,it has been observed that wavelength converters utilizing AlGaAsOI waveguides exhibit suboptimal on-chip wavelength conversion efficiency from the C-band to the 2μm band,generally falling below−20.0 *** address this issue,we present a novel wavelength conversion device assisted by a waveguide amplifier,incorporating both AlGaAs wavelength converter and erbium-ytterbium co-doped waveguide amplifier,thereby achieving a notable conversion efficiency exceeding 0 *** noteworthy enhancement in efficiency can be attributed to the specific dispersion design of the AlGaAs wavelength converter,which enables an upsurge in conversion efficiency to−15.54 dB under 100 mW of pump ***,the integration of an erbium-ytterbium co-doped waveguide amplifier facilitates a loss compensation of over 15 *** the use of external optical amplifiers,this device enables efficient and high-bandwidth wavelength conversion,showing promising applications in various fields,such as optical communication,sensing,imaging,and beyond.

关键词： Silicon-based optoelectronics Wavelength conversion Waveguide amplifier 2μm band

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