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On the detection of closed orbits in time-dependent systems by using double-pulse lasers

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communications in Theoretical Physics 2020年第9期72卷 111-117页

作者： S U Khan m L du Institute of Theoretical Physics Chinese Academy of Sciences.Beijing 100190China University of chinese Academy of Sciences Beijing100049China

In the photodetachment of atoms or negative ions by a double-pulse laser, the first pulse of the double-pulse laser generates waves and the delayed second pulse may detect them. The phenomenon of the excitation and detection of waves by a double-pulse laser can be used to identify the closed orbits in the system. We demonstrate this phenomenon with a negative hydrogen ion(H^-) by analyzing the total population excited by a double-pulse laser in a timedependent field for different physical parameters. By analyzing the total excited population using a double-pulse laser, we can uncover all the closed orbits existing in the system. We demonstrate that this can be realized by scanning the first pulse position and the time delay between the two pulses.

关键词： double-pulse laser detection of closed orbits photodetachment spectra time-dependent systems

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

conserved RB functions in development and tumor suppression

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Protein & cell 2011年第11期2卷 864-878页

作者： Gabriel m.Gordon Wei du Ben may Department for cancer Research University of ChicagoChicagoIL 60637USA

The variety of human cancers in which the retinoblastoma protein pRb is inactivated reflects both its broad importance for tumor suppression and its multitude of cellular *** evidence indicates that pRb contributes to a diversity of cellular functions,including cell proliferation,differentiation,cell death,and genome *** performs these diverse functions through the formation of large complexes that include E2F transcription factors and chromatin *** this review we will discuss some of the recent advances made in understanding the structure and function of pRb as they relate to tumor suppression,and highlight research using Drosophila melanogaster that reveals important,evolutionarily conserved functions of the RB family.

关键词： RB E2F Drosophila Rbf cell cycle chromatin modification

Predicting glass structure by physics-informed machine learning

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npj computational materials 2022年第1期8卷 1839-1847页

作者： mikkel L.Bødker mathieu Bauchy Tao du John c.mauro morten m.Smedskjaer Department of chemistry and Bioscience Aalborg University9220AalborgDenmark Physics of AmoRphous and Inorganic Solids Laboratory(PARISlab) Department of Civil and Environmental EngineeringUniversity of CaliforniaLos AngelesCA90095USA Department of materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA

machine learning(mL)is emerging as a powerful tool to predict the properties of materials,including *** mL models with knowledge of how glass composition affects short-range atomic structure has the potential to enhance the ability of composition-property models to extrapolate accurately outside of their training ***,we introduce an approach wherein statistical mechanics informs a mL model that can predict the non-linear composition-structure relations in oxide *** combined model offers an improved prediction compared to models relying solely on statistical physics or machine learning ***,we show that the combined model accurately both interpolates and extrapolates the structure of Na_(2)O–SiO_(2)***,the model is able to extrapolate predictions outside its training set,which is evidenced by the fact that it is able to predict the structure of a glass series that was kept fully hidden from the model during its training.

关键词： glasses structure glass

coating behavior and surface hardening of Pd_(77)cu_6Si_(17) thin film metallic glass on AZ31 magnesium alloy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 898-905页

作者： X.H.du Y.c.cHANG H.J.PEI B.Y.cHEN m.c.KUO J.c.HUANG School of materials Sciences and Engineering Shenyang Aerospace University Department of materials and Optoelectronic Science National Sun Yat-Sen University Department of materials Engineering Kun Shan University

Pd77cu6Si17(PcS) thin film metallic glasses(TFmGs) with high glass forming ability and hardness were selected as a hard coating for improving the surface hardness of AZ31 magnesium alloy. Both microindentation and nanoindentation tests were conducted on specimens with various PcS film thicknesses from 30 to 2000 nm. The apparent hardness and the relative indentation depth(β) were integrated using a quantitative model. The interaction parameters involved and relative hardness values were extracted from iterative calculations. According to the results, surface hardness can be enhanced greatly by PcS TFmGs in the shallow region, followed by gradual decrease with increasing β ratio. In addition, specimens with thinner coatings(e.g., 200nm) showed greater substrate-film interaction and those with thick coatings(e.g., 2000nm) became prone to film cracking. The optimum TFmG coating thickness in this study was estimated to be around 200 nm.

关键词： Thin film metallic glass(TFmG) magnesium alloy Sputtering process Nanoindentation coating thickness

Preparation of Amorphous Film on Ni-S Alloy by Electroplating method

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chinese chemical Letters 1998年第11期9卷 0-0,0-0页

作者： du, m Gao, RJ Wei, XJ Ocean Univ Qingdao Coll Chem & Chem Engn Qingdao 266003 Peoples R China NE Univ Technol Dept Nonferrrous Met Shenyang 110006 Peoples R China

Beginning from the formation of amorphous alloy film and its use of proAnse, this paper obtains the Ni-S amorphous alloy film by electroplating method using a bath containing Na2S2O3, and considers the deposition conditions in detail. The composition of Ni-S alloy film changes with the cathodic current density, Na2S2O3 content in the bath solution and bath pH, but the structure of the film is detendned by the sulphur content in the deposit. X-ray diffraction (XRD) patterns show that films containing about 15-30% sulphur consist of amorphous alloy. In addition, the process of Ni-S alloy film deposition and the relation between the plating conditions and deposits were studied.

关键词： Ni-S alloy electroplating amorphous structure

Prognostic Evaluation for Oral Squamous cell carcinoma:A Novel method Based on m6A methylation Regulators

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current medical Science 2022年第4期42卷 841-846页

作者： Li XU cheng YU Xi-jin du Department of Stomatology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:This study aimed to examine a novel method for prognostic evaluation of patients with oral squamous cell carcinoma(OScc)based on the expression of heterogeneous nuclear ribonucleoprotein c(HNRNPc),YTH domain-binding protein 2(YTHDF2),and methyltransferase 14(mETTL14).methods:We obtained the RNA sequence and clinical information of OScc patients from The cancer Genome Atlas *** optical method was established by the least absolute shrinkage and selection operator cox regression algorithm,which was used to calculate the risk score of every *** addition,all samples(n=239)were classified into high-risk(n=119)and low-risk(n=120)groups,and the overall survival(OS)time and clinical characteristics were compared between ***,bioinformatics analysis was carried *** set enrichment analysis was performed to investigate the signaling pathways of HNRNPc,YTHDF2,and ***:The two groups showed significantly different OS time,tumor grades,tumor stages,and pathologic T stages(Pceiver operating characteristic analysis identified that our method was effective and it was more accurate than use of age,gender,tumor grade,tumor stage,pathologic T stage,and pathologic N stage in OScc prognostic *** set enrichment analysis revealed that HNRNPc,YTHDF2,and mETTL14 were mainly associated with ubiquitin-mediated proteolysis,cell cycle,RNA degradation,and spliceosome signaling ***:The method based on the expression of HNRNPc,YTHDF2,and mETTL14 can predict the prognosis of patients with OScc independently,and its prognostic value is better than that of clinicopathological characteristic indicators.

关键词： oral squamous cell carcinoma m6A methylation regulators RNA modification prognostic prediction The cancer Genome Atlas

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo centro de Biología molecular Severo Ochoa(cBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

Intrinsically scale-free ferroelectricity in two-dimensional m_(2)X_(2)Y_(6)

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Nano Research 2022年第4期15卷 3704-3710页

作者： Xin Jin Lei Tao Yu-Yang Zhang Jinbo Pan Shixuan du Institute of Physics&University of chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China Songshan Lake materials Laboratory Dongguan 523808China cAS Key Laboratory of Vacuum Physics Beijing 100049China

Discovery of novel two-dimensional(2D)ferroelectric materials and understanding the mechanism are of vital importance for the design of nanoscale ferroelectric ***,we report the distinct geometric evolution mechanism of the newly reported m_(2)Ge_(2)Y_(6)monolayers and find out a large group of 2D ferroelectric candidates based on this *** origination of the ferroelectricity of m_(2)Ge_(2)Y_(6)is the vertical displacement of Ge-dimer in the same direction driven by a soft phonon mode of the centrosymmetric ***,we find another centrosymmetric configuration which is dynamically stable but higher in energy comparing with the ferroelectric *** metastable centrosymmetric phase of m_(2)Ge_(2)Y_(6)monolayers allows a new two-step ferroelectric switching path and may induce novel domain ***,the ferroelectric m_(2)Ge_(2)Y_(6)monolayers exhibit independently switchable dipoles and maintain their ferroelectricity after contacting with graphene electrodes,indicating their high application potentials in high-density ***,16 ferroelectric(FE)m_(2)Ge_(2)Y_(6)and 65 potential FE m2Sn2Y6 monolayers are identified through high-throughput *** findings provide a new strategy for future discovery of novel 2D ferroelectric materials and also platforms for experimental design of related functional devices.

关键词： two-dimensional(2D)materials mechanism of ferroelectricity scale-free ferroelectricity