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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

Stability of the Phase Separation State for Compressible Navier-Stokes/Allen-Cahn System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 45-74页

作者： Ya-zhou chen Hakho Hong Xiao-ding Shi Department of Mathematics College of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing100029China Institute of Mathematics State Academy of SciencesPyongyangKorea

This paper is concerned with the large time behavior of the Cauchy problem for Navier-Stokes/AllenCahn system describing the interface motion of immiscible two-phase flow in 3-D. The existence and uniqueness of global solutions and the stability of the phase separation state are proved under the small initial perturbations. Moreover, the optimal time decay rates are obtained for higher-order spatial derivatives of density,velocity and phase. Our results imply that if the immiscible two-phase flow is initially located near the phase separation state, then under small perturbation conditions, the solution exists globally and decays algebraically to the complete separation state of the two-phase flow, that is, there will be no interface fracture, vacuum, shock wave, mass concentration at any time, and the interface thickness tends to zero as the time t → +∞.

关键词： Navier-Stokes/Allen-Cahn system existence uniqueness large time behavior decay rate

Overshoot phenomena:Observation and simulation

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Earth and Planetary Physics 2024年第2期8卷 391-399页

作者： Ting Feng MoRan Liu ShiMin He Xiang Wang chen zhou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

High-power O-mode radio waves can excite artificial instabilities in the F region,according to experiments conducted at the European Incoherent Scatter Science Association(EISCAT)heating *** main instabilities include the parametric decay instability(PDI),oscillating two-stream instability(OTSI),and thermal parametric instability(TPI).The PDI and OTSI not only compete with each other,but also compete with the TPI,leading to a two-stage overshoot phenomenon:a miniovershoot occurs on a millisecond time scale after pump-on,followed by the main *** gain insight into the miniovershoot via a generalized Zakharov model,whereas the main overshoot can be observed as an enhanced plasma line overshoot phenomenon in incoherent scatter radar *** can also observe that the zero-frequency ion line exists only in the initial heating period after a cold start and that the upshifted and downshifted ion lines behave irregularly in the *** simulation results show that competition between the PDI and OTSI leads to an initial peak,which we named the *** following processes,namely ion density caviton generation,and collapse and cascade in the development of the PDI,contribute to the miniovershoot phenomenon.

关键词： overshoot parametric decay instability oscillating two-stream instability competition

Noninvasive Diagnostic Technique for Nonalcoholic Fatty Liver Disease Based on Features of Tongue Images

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Chinese Journal of Integrative Medicine 2024年第3期30卷 203-212页

作者： WANG Rong-rui chen Jia-liang DUAN Shao-jie LU Ying-xi chen Ping zhou Yuan-chen YAO Shu-kun Graduate School of Beijing University of Chinese Medicine Beijing100029China Department of Gastroenterology China-Japan Friendship HospitalBeijing100029China Center of Integrative Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing100015China Nanjing Linkwah Micro-electronics Institute Beijing100191China Institute of Microelectronics Tsinghua UniversityBeijing100084China Peking University China-Japan Friendship School of Clinical Medicine Beijing100029China

Objective:To investigate a new noninvasive diagnostic model for nonalcoholic fatty liver disease(NAFLD) based on features of tongue ***:Healthy controls and volunteers confirmed to have NAFLD by liver ultrasound were recruited from China-Japan Friendship Hospital between September 2018 and May 2019,then the anthropometric indexes and sampled tongue images were *** tongue images were labeled by features,based on a brief protocol,without knowing any other clinical data,after a series of corrections and data *** algorithm was trained on images using labels and several anthropometric indexes for inputs,utilizing machine learning ***,a logistic regression algorithm and a decision tree model were constructed as 2 diagnostic models for ***:A total of 720 subjects were enrolled in this study,including 432 patients with NAFLD and 288 healthy *** them,482 were randomly allocated into the training set and 238 into the validation *** diagnostic model based on logistic regression exhibited excellent performance:in validation set,it achieved an accuracy of 86.98%,sensitivity of 91.43%,and specificity of 80.61%;with an area under the curve(AUC) of 0.93 [95% confidence interval(CI) 0.68–0.98].The decision tree model achieved an accuracy of 81.09%,sensitivity of 91.43%,and specificity of 66.33%;with an AUC of 0.89(95% CI 0.66–0.92) in validation ***:The features of tongue images were associated with *** the 2 diagnostic models,which would be convenient,noninvasive,lightweight,rapid,and inexpensive technical references for early screening,can accurately distinguish NAFLD and are worth further study.

关键词： nonalcoholic fatty liver disease noninvasive diagnosis tongue image tongue diagnosis Chinese medicine machine learning

A case study of continental shelf waves in the northwestern South China Sea induced by winter storms in 2021

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Acta Oceanologica Sinica 2024年第1期43卷 59-69页

作者： Junyi Li chen zhou Min Li Quanan Zheng Mingming Li Lingling Xie Laboratory of Coastal Ocean Variation and Disaster Prediction College of Ocean and MeteorologyGuangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environments in Continent Shelf Sea and Deep OceanDepartment of Education of Guangdong ProvinceZhanjiang 524088China Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural ResourcesBeijing 100081China Department of Atmospheric and Oceanic Science University of MarylandCollege ParkMaryland 20742USA

This study aims to investigate characteristics of continental shelf wave(CSW)on the northwestern continental shelf of the South China Sea(SCS)induced by winter storms in *** and cruise observations,tidal gauge data at stations Hong Kong,Zhapo and Qinglan and sea surface wind data from January 1 to February 28,2021 are used to examine the relationship between along-shelf wind and sea level *** events of CSWs driven by the along-shelf sea surface wind are detected from wavelet spectra of tidal gauge *** signals are triply peaked at periods of 56 h,94 h and 180 h,propagating along the coast with phase speed ranging from 6.9 m/s to18.9 m/*** dispersion relation shows their property of the Kelvin mode of *** develop a simple method to estimate amplitude of sea surface fluctuation by along-shelf *** results are comparable with the observation data,suggesting it is *** mode 2 CSWs fits very well with the mooring current velocity *** results from rare current help to understand wave-current interaction in the northwestern SCS.

关键词： continental shelf waves Ekman transport Kelvin mode wavelet analysis northwestern South China Sea

A review on electrocatalytic CO_(2) conversion via C-C and C-N coupling

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Carbon Energy 2024年第2期6卷 167-194页

作者： Zhuangzhi Zhang Sijun Li Zheng Zhang zhou chen Hua Wang Xianguang Meng Wenquan Cui Xiwei Qi Jiacheng Wang Hebei Provincial Laboratory of Inorganic Nonmetallic Materials College of Materials Science and EngineeringNorth China University of Science and TechnologyTangshanChina Key Laboratory of Luminescence Analysis and Molecular Sensing Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqingChina State Key Laboratory of New Textile Materials and Advanced Processing Technologies Hubei Key Laboratory of Biomass Fibers and Eco-Dyeing and FinishingCollege of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhanChina College of Materials Xiamen UniversityXiamenChina Hebei Iron and Steel Laboratory TangshanChina Hebei Key Laboratory for Environment Photocatalytic and Electrocatalytic Materials College of Chemical EngineeringNorth China University of Science and TechnologyTangshanChina College of Metallurgy and Energy North China University of Science and TechnologyTangshanChina State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghaiChina Institute of Electrochemistry School of Materials Science and EngineeringTaizhou UniversityTaizhouChina

Electrochemical C-C and C-N coupling reactions with the conversion of abundant and inexpensive small molecules,such as CO_(2) and nitrogencontaining species,are considered a promising route for increasing the value of CO_(2) reduction *** development of high-performance catalysts is the key to the both electrocatalytic *** this review,we present a systematic summary of the reaction systems for electrocatalytic CO_(2) reduction,along with the coupling mechanisms of C-C and C-N bonds over outstanding electrocatalytic materials recently *** key intermediate species and reaction pathways related to the coupling as well as the catalyst-structure relationship will be also discussed,aiming to provide insights and guidance for designing efficient CO_(2) reduction systems.

关键词： C-C coupling C-N coupling CO_(2) conversion electrocatalysis urea synthesis

Sharp Interface Limit for the One-dimensional Compressible Navier-Stokes/Allen-Cahn System with Composite Waves

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Acta Mathematicae Applicatae Sinica 2024年

作者： Ya-zhou chen Yi PENG Xiao-ding SHI School of Mathematics and Physics Beijing University of Chemical Technology

This paper is concerned with the sharp interface limit of Cauchy problem for the one-dimensional compressible Navier-Stokes/Allen-Cahn system with a composite wave consisting of the superposition of a rarefaction wave and a shock wave. Under the assumption that the viscosity coefficient and the reciprocal of mobility coefficient are directly proportional to the interface thickness, we first convert the sharp interface limit of the system into the large time behavior of the composite wave via a natural scaling. Then we prove that the composite wave is asymptotically stable under the small initial perturbations and the small strength of the rarefaction and shock wave. Finally, we show the solution of the Cauchy problem exists for all time, and converges to the composite wave solution of the corresponding Euler equations as the thickness of the interface tends to zero. The proof is mainly based on the energy method and the relative entropy.

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Dual neovascular targets of vascular endothelial growth factor receptors and platelet-derived growth factor receptor ameliorate thioacetamide induced liver fibrosis in rats

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Portal Hypertension & Cirrhosis 2024年第1期3卷 1-13页

作者： Bin Xiong Yaowei Bai Jiacheng Liu Tongqiang Li Yingliang Wang chen zhou Department of Interventional Radiology The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdongChina Department of Radiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiChina Hubei Province Key Laboratory of Molecular Imaging WuhanHubeiChina

Aims:Neovascularization plays a crucial role in liver fibrosis(LF),and blocking vascular endothelial growth factor receptors(VEGFR)has been shown to improve *** aim of our study was to investigate the role of dual neovascularization targets,VEGFR,and platelet-derived growth factor receptor(PDGFR),in ameliorating ***:In vitro,we observed the effects of apatinib(APA)(a VEGFR inhibitor)and donafenib(DON)(a VEGFR and PDGFR inhibitor)on the activation,proliferation,and apoptosis of hepatic stellate cells(HSCs)from rats and *** vivo,we established a thioacetamide(TAA)-induced liver fibrosis rat model to explore the antifibrosis effect of APA and *** used the method of random table to randomly divide the rats into 4 *** detected the expression of angiogenesis-related proteins using Western blot and ***:APA and DON inhibited the proliferation and activation of HSCs,promoted apoptosis of HSCs,and arrested the S phase of the cell cycle in *** also found that DON had a stronger inhibitory effect on *** vivo,APA and DON ameliorated liver fibrosis,reduced collagen deposition andα-SMA expression in rats,and DON had a stronger improvement *** and DON downregulated the expression of VEGFR2 while inhibiting the phosphorylation of Akt and ERK1/*** can act through both VEGF and PDGF pathways,whereas APA can only act through the VEGF ***:Antiangiogenesis is a promising approach for the treatment of *** with a single-target drug(APA),the dual-target drug(DON)can achieve better therapeutic effects.

关键词： antiangiogenesis apatinib donafenib fibrosis

Wide hybridizations reveal the robustness of functional centromeres in Triticum-Aegilops species complex lines

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Journal of Genetics and Genomics 2024年第5期51卷 570-573页

作者： Yuhong Huang Qinghua Shi chen zhou Chunhui Wang Yang Liu Congyang Yi Handong Su Fangpu Han State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Bejing 100049China National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubei430070China

The Triticum-Aegilops complex groups demonstrated high cross-affinity with each other to overcome the barriers of distant hybridization(Loureiro et al.,2023).Distant hybridization involves two distinct yet closely related events:hybridization and genome *** studies have indicated that bursts of transposable elements(TEs)can occur as a consequence or concomitant to hybridization or genome duplication(Parisod et al.,2010).This raises an important scientific question regarding how the TEs-rich centromere region copes with genomic shock(McClintock,1984).The Triticum-Aegilops species complexes,particularly in the F1,So,and subsequent early generations resulting from successive selfcrossing,offer an opportunity to investigate whether the centromere environment undergoes reconstruction and the associated mechanisms that maintain genomic stability.

关键词： centromere Triticum complex