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Genetic and epigenetic control of transfer cell development in plants

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Journal of Genetics and Genomics 2016年第9期43卷 533-539页

作者： Jing Yuan perry Bateman Jose Gutierrez-Marcos State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of Sciences School of Life Sciences University of Warwick

The inter-cellular translocation of nutrients in plant is mediated by highly specialized transfer cells （TCs）. TCs share similar functional and structural features across a wide range of plant species, including location at plant exchange surfaces, rich in secondary wall ingrowths, facilitation of nutrient flow, and passage of select molecules. The fate of endosperm TCs is determined in the TC fate acquisition stage （TCF）, before the structure features are formed in the TC differentiation stage （TCD）. At present, the molecular basis of TC development in plants remains largely unknown. In this review, we summarize the important roles of the signaling molecules in different development phases, such as sugars in TCF and phytohormones in TCD, and discuss the genetic and epigenetic factors, including TC-specific genes and endogenous plant peptides, and their crosstalk with these signaling molecules as a complex regulatory network in regulation of TC develonment in olants.

关键词： Transfer cells Differentiation Signals and genes network

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Tunable fiber Bragg grating filters realized by chirp rate tuning with a cantilever beam

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Frontiers of Optoelectronics 2010年第1期3卷 71-77页

作者： Xinyong DONG perry Ping SHUM Institute of Optoelectronic Technology China Jiliang University Network Technology Research Centre Nanyang Technological University

An efficient scheme to change the chirp rate of a fiber Bragg grating(FBG) has been developed based on a specially-designed cantilever beam with the beam-bending method. It allows, to date, the largest tuning range of 36 nm in reflection bandwidth of a chirped-FBG(CFBG) while keeping the center wavelength nearly fixed during the tuning process. Using this method, bandwidth-tunable fiber grating filters with tunable chromatic dispersion or differential group delay have been demonstrated. Channel spacing-tunable multi-wavelength filters based on both sampled- and superimposed-CFBGs have also been realized. Moreover, tuning of the bandwidth and channel spacing is continuous with this scheme that makes the achieved devices more flexible.

关键词： optical filter fiber Bragg grating multiwavelength filter bandwidth-tunable filter

Id1 has a physiological role in regulating early B lymphopoiesis

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Cellular & Molecular Immunology 2011年第1期8卷 41-49页

作者： Shawn W Cochrane Ying Zhao S Scott perry Thomas Urbaniak Xiao-Hong Sun Immunobiology and Cancer Research Program Oklahoma Medical Research FoundationOklahoma CityOKUSA Department of Cell Biology University of Oklahoma Health Sciences CenterOklahoma CityOKUSA

Basic helix–loop–helix E proteins play critical roles in B-cell development by stimulating B cell-specific gene expression and immunoglobulin gene *** function of E proteins can be effectively suppressed by their naturally occurring inhibitors,Id1 to *** expression of Id1 has been shown to block B-cell development at the early pro-B cell ***,whether Id1 plays a physiological role in controlling B lymphopoiesis was not *** Id1-deficient mice do not exhibit significant abnormalities in steady-state B lymphopoiesis,we detected more robust B-cell engraftment in transplant recipients of Id1-deficient bone marrow compared to those of wild-type donor *** culture,Id1 ablation dramatically enhances B-lineage cell production without any marked effects on myeloid ***,Id1 expression was found in pro-B but not pre-B cells as measured by enhanced green fluorescent protein(EGFP)fluorescence and by quantitative reverse *** loss of Id1 did not alter the number of B-cell colonies generated from whole bone marrow or the proliferation rate of developing B cells,B-cell colonies were detectable at a much earlier time point and the size of the colonies were ***,we infer that Id1-deficient progenitors possess higher potential to differentiate to the pre-B cell stage when a proliferative burst *** together,we present evidence to suggest that Id1 plays a physiological role in restraining the developmental progression,which may be important for proper B-cell differentiation in the bone marrow.

关键词： Id1 helix-loop-helix E2A B cell differentiation

Time-slot multiplexing based bandwidth enhancement for fiber distributed acoustic sensing

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Science China(Information Sciences) 2022年第1期65卷 292-293页

作者： Hao LI Cunzheng FAN Tao LIU Yujia LIU Zhijun YAN perry SHUM Qizhen SUN National Engineering Laboratory for Next Generation Internet Access System Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Sicence and Technology Department of Electrical and Electronic Engineering Southern University of Science and Technology

Dear editor,The phase-sensitive optical time-domain reflectometry(φ-OTDR) has been demonstrated as the most common technique in fiber distributed acoustic sensing(DAS). However,traditional φ-OTDR based DAS suffered from the inherent trade-off between the maximum frequency response and the distance which can be characterized by distance bandwidth product(DBP), since the time interval of the probe pulses should be larger than the pulse round-trip flight time.

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The host type I interferon response to viral and bacterial infections

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Cell Research 2005年第6期15卷 407-422页

作者： Andrea K. perry Department of Microbiology Immunology and Molecular Genetics University of California Los Angeles Los Angeles CA 90095 USA

Type I interferons (IFN) are well studied cytokines with anti-viral and immune-modulating functions. Type I IFNsare produced following viral infections, but until recently, the mechanisms of viral recognition leading to IFN productionwere largely unknown. Toll like receptors (TLRs) have emerged as key transducers of type I IFN during viral infectionsby recognizing various viral components. Furthermore, much progress has been made in defining the signaling path-ways downstream of TLRs for type I IFN production. TLR7 and TLR9 have become apparent as universally importantin inducing type I IFN during infection with most viruses, particularly by plasmacytoid dendritic cells. New intracellularviral pattern recognition receptors leading to type I IFN production have been identified. Many bacteria can also inducethe up-regulation of these cytokines. Interestingly, recent studies have found a detrimental effect on host cells if type IIFN is produced during infection with the intracellular gram-positive bacterial pathogen, Listeria monocytogenes. Thisreview will discuss the recent advances made in defining the signaling pathways leading to type I IFN production.

关键词： type I interferons Toll-like receptors pattern-recognition receptors virus infections Listeria monocytogenes signaling mechanisms.

An optical fiber network oracle for NP-complete problems

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Light(Science & Applications) 2014年第1期3卷 304-308页

作者： Kan Wu Javier Garcia de Abajo Cesare Soci perry Ping Shum Nikolay I Zheludev Centre for Disruptive Photonic Technologies Nanyang Technological UniversitySingapore 637371Singapore Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK IQFR-CSIC 28006 MadridSpain

The modern information society is enabled by photonic fiber networks characterized by huge coverage and great complexity and ranging in size from transcontinental submarine telecommunication cables to fiber to the home and local *** world-wide network has yet to match the complexity of the human brain,which contains a hundred billion neurons,each with thousands of synaptic connections on ***,it already exceeds the complexity of brains from primitive organisms,i.e.,the honey bee,which has a brain containing approximately one million *** this study,we present a discussion of the computing potential of optical networks as information *** a simple fiber network,we provide a proof-of-principle demonstration that this network can be treated as an optical oracle for the Hamiltonian path problem,the famous mathematical complexity problem of finding whether a set of towns can be travelled via a path in which each town is visited only *** of a Hamiltonian path is achieved by monitoring the delay of an optical pulse that interrogates the network,and this delay will be equal to the sum of the travel times needed to visit all of the nodes(towns).We argue that the optical oracle could solve this NP-complete problem hundreds of times faster than brute-force ***,we discuss secure communication applications for the optical oracle and propose possible implementation in silicon photonics and plasmonic networks.

关键词： Hamiltonian path problem NP complete optical oracle

Posttranslational modifications of α-tubulin in alzheimer disease

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Translational Neurodegeneration 2015年第1期4卷 59-67页

作者： Fan Zhang Bo Su Chunyu Wang Sandra L.Siedlak Siddhartha Mondragon-Rodriguez Hyoung-gon Lee Xinglong Wang George perry Xiongwei Zhu Department of Pathology Case Western Reserve UniversityClevelandOH 44121USA Department of Neurosurgery Shandong Provincial HospitalShandong UniversityJinan 250012China Department of Neurobiology Shandong UniversityJinan 250012China Department of Neurology the Second Xiangya HospitalCentral South UniversityChangshaHunan 410011China Departamento de Neurobiología del Desarrollo y Neurofisiología Instituto de NeurobiologíaUniversidad Nacional Autónoma de México QuerétaroQuerétaro MéxicoD.F.Mexico The University of Texas at San Antonio One UTSA CircleSan AntonioTX 78249USA 2103 Cornell Road ClevelandOH 44106USA

Background:In Alzheimer disease(AD),hyperphosphorylation of tau proteins results in microtubule destabilization and cytoskeletal *** prior ultra-morphometric studies documented a clear reduction in microtubules in pyramidal neurons in AD compared to controls,however,this reduction did not coincide with the presence of paired helical *** latter suggests the presence of compensatory mechanism(s)that stabilize microtubule dynamics despite the loss of tau binding and *** are composed of tubulin dimers which are subject to posttranslational modifications that affect the stability and function of ***:In this study,we performed a detailed analysis on changes in the posttranslational modifications in tubulin in postmortem human brain tissues from AD patients and age-matched controls by immunoblot and ***:Consistent with our previous study,we found decreased levels ofα-tubulin in AD *** of tubulin with various posttranslational modifications such as polyglutamylation,tyrosination,and detyrosination were also proportionally reduced in AD brain,but,interestingly,there was an increase in the proportion of the acetylatedα-tubulin in the remainingα-*** distribution was changed from predominantly in the processes to be more accumulated in the cell *** number of processes containing polyglutamylated tubulin was well preserved in AD *** there was a cell autonomous detrimental effect of NFTs on tubulin,this is likely a gradual and slow process,and there was no selective loss of acetylated or polyglutamylated tubulin in NFT-bearing ***:Overall,we suggest that the specific changes in tubulin modification in AD brain likely represent a compensatory response.

关键词： Acetylation Alzheimer disease Polyglutamylation Tau Tubulin

Dynamics of cavity soliton driven by chirped optical pulses in Kerr resonators

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Frontiers of Optoelectronics 2022年第1期15卷 156-163页

作者： Jianxing Pan Chaoyu Xu Zhichao Wu Jing Zhang Tianye Huang perry Ping Shum School of Mechanical Engineering and Electronic Information China University of Geosciences(Wuhan)Wuhan 430074China Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China

Recent researches have demonstrated that pulsed driving is an effective method to increase the temporal overlap between cavity soliton(CS)and pump field,thereby increasing the pump-to-comb conversion *** amplitude-modulated inhomogeneity of the background wave causes the solitons to drift toward edges of the driving *** eliminate the mul-tiple temporal trapping positions,induced by the spontaneous symmetry breaking,we propose the chirped pulse driving for deterministic single soliton *** theoretically explain the physical mechanism of the chirp pulse driving,as the combination of amplitude and phase *** numerical simulations demonstrate the chirp is responsible for the single soliton generation.A detailed investigation for dynamics of CSs sustained by chirped pulses,shows the recovery of spontaneous symmetry *** addition,the desynchronized chirped pulse driving is also considered *** a weak chirp parameter,the desynchronization-dependent trapping position diagram is divided into multiple areas including two CSs,a single CS,two oscillating CSs,and no *** a sufficient chirp parameter considered,the trapping position curve becomes a monotonous function of the desynchronized drift velocity,which indicates deterministic single soliton generation.

关键词： Cavity soliton(CS) Chirped pulse driving Deterministic single soliton

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Fiber structures and material science in optical fiber magnetic field sensors

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Frontiers of Optoelectronics 2022年第3期15卷 55-71页

作者： Jing Zhang Chen Wang Yunkang Chen Yudiao Xiang Tianye Huang perry Ping Shum Zhichao Wu School of Mechanical Engineering and Electronic Information China University of Geosciences(Wuhan)Wuhan 430074China Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China

Magnetic feld sensing plays an important role in many felds of scientifc research and engineering *** from the advantages of optical fbers,the optical fber-based magnetic feld sensors demonstrate characteristics of light weight,small size,remote controllability,reliable security,and wide dynamic *** paper provides an overview of the basic principles,development,and applications of optical fber magnetic feld *** sensing mechanisms of fber grating,interferometric and evanescent feld fber are discussed in *** fuid materials,magneto-strictive materials,and magneto-optical materials used in optical fber sensing systems are also *** applications of optical fber magnetic feld sensors as current sensors,geomagnetic monitoring,and quasi-distributed magnetic sensors are *** addition,challenges and future development directions are analyzed.

关键词： Optical fber magnetic feld sensors Optical fber structures Magnetically sensitive materials Optical fber current sensors Geomagnetic monitoring Distributed magnetic felds sensors

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