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Ultrafast optical investigation of carrier and spin dynamics in low-dimensional perovskites

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Science China(Technological Sciences) 2024年第1期67卷 2-18页

作者： fu JinYue JIANG ying FANG HongHua Key Laboratory for Micro-Nano Physics and Technology of Hunan Province School of Physics and ElectronicsHunan UniversityChangsha 410012China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Low-dimensional perovskite(PVK)materials have attracted significant research interest,because of their quantum-confined effect,tunable band gap structures,and higher stability than that of three-dimensional(3D)PVKs.In semiconductor optoelectronic devices,high speed and small size are closely interlinked.The development of high-speed devices requires researchers to fully understand the properties of materials,especially the dynamic processes such as carrier recombination,separation,and transport,which often play a crucial role in the performance of devices.As an indispensable part of dynamic research,spin relaxation is also of great significance in studying the properties of materials and explore possible applications.Lead halide PVK materials have strong spin-orbit coupling(SOC),which provides a basis for information storage and processing by using spin degrees of freedom.Therefore,studying the carrier and spin dynamics of low-dimensional PVKs is an effective way to understand the internal properties of low-dimensional PVKs clearly.This paper summarizes the latest research progress on the ultrafast carrier and spin dynamics in low-dimensional PVKs,to comprehensively understand their carrier and spin behaviors and present an outlook for relevant studies in this area.

关键词： low-dimensional perovskites carrier dynamics spin dynamics optoelectronic devices

Recursive filtering of multi-rate cyber-physical systems with unknown inputs under adaptive event-triggered mechanisms

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 250-259页

作者： ying SUN Miaomiao fu Jingyang MAO Guoliang WEI Business School University of Shanghai for Science and TechnologyShanghai200093China Shanghai Caoyang Vocational School Shanghai200333China School of Electrical and Electronic Engineering Shanghai Institute of TechnologyShanghai201418China School of Intelligent Emergency Management University of Shanghai for Science and TechnologyShanghai200093China

Cyber-physical systems(CPSs)take on the characteristics of both multiple rates of information collection and processing and the dependency on information exchanges.The purpose of this paper is to develop a joint recursive filtering scheme that estimates both unknown inputs and system states for multi-rate CPSs with unknown inputs.In cyberspace,the information transmission between the local joint filter and the sensors is governed by an adaptive event-triggered strategy.furthermore,the desired parameters of joint filters are determined by a set of algebraic matrix equations in a recursive way,and a sufficient condition verifying the boundedness of filtering error covariance is found by resorting to some algebraic operation.A state fusion estimation scheme that uses local state estimation is proposed based on the covariance intersection(CI)based fusion conception.Lastly,an illustrative example demonstrates the effectiveness of the proposed adaptive event-triggered recursive filtering algorithm.

关键词： Cyber-physical systems Multi-rate Joint recursive filtering Adaptive event-triggered mechanisms Unknown inputs

Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils

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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen ying-Shun Zhu fu-San Chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China Institute of High Energy Physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and serpentine.However,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications difficult.Compared with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical studies.In this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are presented.The analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current density.Then,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

ELABELA-derived peptide ELA13 attenuates kidney fibrosis by inhibiting the Smad and ERK signaling pathways

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 341-353页

作者： Zhibin YAN ying SHI Runling YANG Jijun XUE Caiyun fu Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou310018China State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University Lanzhou 730000China Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical Sciences&Research Unit of Peptide ScienceChinese Academy of Medical Sciences2019RU066Lanzhou UniversityLanzhou 730000China

Kidney fibrosis is an inevitable result of various chronic kidney diseases(CKDs)and significantly contributes to end-stage renal failure.Currently,there is no specific treatment available for renal fibrosis.ELA13(amino acid sequence:RRCMPLHSRVPFP)is a conserved region of ELABELA in all vertebrates;however,its biological activity has been very little studied.In the present study,we evaluated the therapeutic effect of ELA13 on transforming growth factor-β1(TGF-β1)-treated NRK-52E cells and unilateral ureteral occlusion(UUO)mice.Our results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum,and reduce the expression of fibrosis biomarkers confirmed by Masson staining,immunohistochemistry,real-time polymerase chain reaction(RT-PCR),and western blot.Inflammation biomarkers were increased after UUO and decreased by administration of ELA13.furthermore,we found that the levels of essential molecules in the mothers against decapentaplegic(Smad)and extracellular signal-regulated kinase(ERK)pathways were reduced by ELA13 treatment in vivo and in vitro.In conclusion,ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.

关键词： ELA13 Kidney fibrosis Inflammation Smad Extracllular signal-regulated kinase(ERK)

Hierarchical vectorization for facial images

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Computational Visual Media 2024年第1期10卷 97-118页

作者： Qian fu Linlin Liu Fei Hou ying He School of Computer Science and Engineering Nanyang Technological University639798SingaporeSingapore Data61 Commonwealth Scientific and Industrial Research OrganisationSydney2015Australia Interdisciplinary Graduate School Nanyang Technological University and Alibaba Group639798SingaporeSingapore State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

The explosive growth of social media means portrait editing and retouching are in high demand.While portraits are commonly captured and stored as raster images,editing raster images is non-trivial and requires the user to be highly skilled.Aiming at developing intuitive and easy-to-use portrait editing tools,we propose a novel vectorization method that can automatically convert raster images into a 3-tier hierarchical representation.The base layer consists of a set of sparse diffusion curves(DCs)which characterize salient geometric features and low-frequency colors,providing a means for semantic color transfer and facial expression editing.The middle level encodes specular highlights and shadows as large,editable Poisson regions(PRs)and allows the user to directly adjust illumination by tuning the strength and changing the shapes of PRs.The top level contains two types of pixel-sized PRs for high-frequency residuals and fine details such as pimples and pigmentation.We train a deep generative model that can produce high-frequency residuals automatically.Thanks to the inherent meaning in vector primitives,editing portraits becomes easy and intuitive.In particular,our method supports color transfer,facial expression editing,highlight and shadow editing,and automatic retouching.To quantitatively evaluate the results,we extend the commonly used FLIP metric(which measures color and feature differences between two images)to consider illumination.The new metric,illumination-sensitive FLIP,can effectively capture salient changes in color transfer results,and is more consistent with human perception than FLIP and other quality measures for portrait images.We evaluate our method on the FFHQR dataset and show it to be effective for common portrait editing tasks,such as retouching,light editing,color transfer,and expression editing.

关键词： face editing vectorization Poisson editing color transfer illumination editing expression editing

Hydroxysafflor yellow A induced ferroptosis of Osteosarcoma cancer cells by HIF-1α/HK2 and SLC7A11 pathway

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Oncology Research 2024年第5期32卷 899-910页

作者： YIWEN ZHU LIU YANG ying YU ying XIONG PING XIAO XIAO fu XIN LUO Department of Rehabilitation Medicine The Second Affiliated Hospital of Nanchang UniversityNanchang330006China Department of General Practice The Second Affiliated Hospital of Nanchang UniversityNanchang330006China

Osteosarcoma is a very serious primary bone cancer with a high death rate and a dismal prognosis.Since there is no permanent therapy for this condition,it is necessary to develop a cure.Therefore,this investigation was carried out to assess the impacts and biological functions of hydroxysafflor yellow A(HYSA)in osteosarcoma cell lines(MG63).In this investigational study,MG63 cells were utilized.Microarray experiments,quantitative polymerase chain reaction(qPCR),immunofluorescent staining,extracellular acidification rate(ECAR),oxygen consumption rate(OCR),glucose consumption,lactate production,and ATP levels,proliferation assay,5-Ethynyl-2′-deoxyuridine(EDU)staining,and Western blot were performed.In MG63 cells,HYSA lowered cell proliferation and metastasis rates,suppressed EDU cell number,and enhanced caspase-3/9 activity levels.HYSA reduced the Warburg effect and induced ferroptosis(FPT)in MG63 cells.Inhibiting ferroptosis diminished HYSA’s anti-cancer activities in MG63 cells.The stimulation of the HIF-1α/SLC7A11 pathway decreased HYSA’s anti-cancer activities in MG63 cells.HIF-1αis one target spot for HYSA in a model of osteosarcoma cancer(OC).HYSA altered HIF-1α’s thermophoretic activity;following binding with HYSA,HIF-1α’s melting point increased from~55°C to~60°C.HYSA significantly enhanced the thermal stability of exogenous WT HIF-1αwhile not affecting Mut HIF-1α,suggesting that ARG-311,GLY-312,GLN-347,and GLN-387 may be involved in the interaction between HIF-1αand HYSA.Conclusively,our study revealed that HYSA induced FPT and reduced the Warburg effect of OC through mitochondrial damage by HIF-1α/HK2/SLC7A11 pathway.HYSA is a possible therapeutic option for OC or other cancers.

关键词： Hydroxysafflor yellow A Osteosarcoma HIF-1α FPT

Analysis of amino acid enantiomers in ambient aerosols:Effects and removal of coexistent aerosol matrix

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Journal of Environmental Sciences 2024年第3期137卷 732-740页

作者： ying Li Xiaoying Li Libin Wu Luhan Shi ShanWang Pingqing fu yingyi Zhang Senchao Lai The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China now at Hong Kong University of Science and Technology Hong Kong 00852China

Amino acids(AAs)including D-and L-enantiomers are a group of organic nitrogen species in ambient aerosol.Due to the low abundances of AAs(level of ng/m^(3))and the matrix effects by coexistent components,it is challenging to quantify AA enantiomers in ambient aerosols especially under pollution conditions.In this study,we present an optimized method for analyzing AA enantiomers in atmospheric aerosol samples including a pretreatment process and the detection by high performance liquid chromatography coupled to a fuorescence detector(HPLC-FLD).Matrix effects caused by coexistent chemicals on AA enantiomers analysis in ambient aerosol samples were investigated especially for those collected in pollution episodes.The results revealed that the determination of AA enantiomers is significantly affected by the coexistent organic carbon(as a proxy of organic matter)and water-soluble ion of NH_(4)^(+).To remove the matrix effects,we applied a pretreatment using the solid phase extraction column coupled with alkaline adjustment to sample extract.After pretreatment,18 AAs including 6 pairs of D-and L-enantiomers(i.e.,leucine,isoleucine,valine,alanine,serine,and aspartic acid)can be successfully separated and quantified in aerosol samples by HPLC-FLD.The recoveries are in the range of 67%-106%.This method was successfully applied to the urban aerosol samples from pollution and non-pollution periods for AA enantiomers determination.We suggest that the concentrations of D-AAs and the ratio of D-AA/L-AA are indicative of the contribution of bacterial sources and the infuence of biomass burning.

关键词： Amino acid enantiomers Atmospheric aerosol Organic carbon Ammonia Chiral ratio

Revealing the role of CCoAOMT1: fine-tuning bHLH transcription factors for optimal anther development

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Science China(Life Sciences) 2024年第3期67卷 565-578页

作者： Zesen Lai Jianzheng Wang ying fu Menghan Wang Hong Ma Shiqing Peng Fang Chang State Key Laboratory of Genetic Engineering Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering and Institute of Biodiversity SciencesInstitute of Plant BiologySchool of Life SciencesFudan UniversityShanghai 200438China School of Tropical Agriculture and Forestry Agriculture-Rural Affairs and Rural RevitalizationHainan UniversityHaikou 570228China Key Laboratory of Biology and Genetic Resources of Tropical Crops Ministry of AgricultureInstitute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikou 571101China Department of Biology Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPA 16802USA

The tapetum,a crucial innermost layer encompassing male reproductive cells within the anther wall,plays a pivotal role in normal pollen development.The transcription factors (TFs) bHLH010/089/091 redundantly facilitate the rapid nuclear accumulation of DYSfuNCTIONAL TAPETUM 1,a gatekeeper TF in the tapetum.Nevertheless,the regulatory mechanisms governing the activity of bHLH010/089/091 remain unknown.In this study,we reveal that caffeoyl coenzyme A O-methyltransferase 1 (CCoAOMT1) is a negative regulator affecting the nuclear localization and function of bHLH010 and bHLH089,probably through their K259 site.Our findings underscore that CCoAOMT1 promotes the nuclear export and degradation of bHLH010 and bHLH089.Intriguingly,elevated CCoAOMT1 expression resulted in defective pollen development,mirroring the phenotype observed in bhlh010 bhlh089 mutants.Moreover,our investigation revealed that the K259A mutation in the bHLH089 protein disrupted its translocation from the nucleus to the cytosol and impeded its degradation induced by CCoAOMT1.Importantly,transgenic plants with the probHLH089::bHLH089^(K259A)construct failed to rescue proper pollen development or gene expression in bhlh010 bhlh089 mutants.Collectively,these findings emphasize the need to maintain balanced TF homeostasis for male fertility.They firmly establish CCoAOMT1 as a pivotal regulator that is instrumental in achieving equilibrium between the induction of the tapetum transcriptional network and ensuring appropriate anther development.

关键词： anther development nuclear localization bHLH O-methyltransferase transcription factor homeostasis

A Video Captioning Method by Semantic Topic-Guided Generation

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Computers, Materials & Continua 2024年第1期78卷 1071-1093页

作者： Ou Ye Xinli Wei Zhenhua Yu Yan fu ying Yang College of Computer Science and Technology Xi’an University of Science and TechnologyXi’an710054China

In the video captioning methods based on an encoder-decoder,limited visual features are extracted by an encoder,and a natural sentence of the video content is generated using a decoder.However,this kind ofmethod is dependent on a single video input source and few visual labels,and there is a problem with semantic alignment between video contents and generated natural sentences,which are not suitable for accurately comprehending and describing the video contents.To address this issue,this paper proposes a video captioning method by semantic topic-guided generation.First,a 3D convolutional neural network is utilized to extract the spatiotemporal features of videos during the encoding.Then,the semantic topics of video data are extracted using the visual labels retrieved from similar video data.In the decoding,a decoder is constructed by combining a novel Enhance-TopK sampling algorithm with a Generative Pre-trained Transformer-2 deep neural network,which decreases the influence of“deviation”in the semantic mapping process between videos and texts by jointly decoding a baseline and semantic topics of video contents.During this process,the designed Enhance-TopK sampling algorithm can alleviate a long-tail problem by dynamically adjusting the probability distribution of the predicted words.Finally,the experiments are conducted on two publicly used Microsoft Research Video Description andMicrosoft Research-Video to Text datasets.The experimental results demonstrate that the proposed method outperforms several state-of-art approaches.Specifically,the performance indicators Bilingual Evaluation Understudy,Metric for Evaluation of Translation with Explicit Ordering,Recall Oriented Understudy for Gisting Evaluation-longest common subsequence,and Consensus-based Image Description Evaluation of the proposed method are improved by 1.2%,0.1%,0.3%,and 2.4% on the Microsoft Research Video Description dataset,and 0.1%,1.0%,0.1%,and 2.8% on the Microsoft Research-Video to Text dataset,respectively,compared with the existing video c

关键词： Video captioning encoder-decoder semantic topic jointly decoding Enhance-TopK sampling