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A special kind of local structure in the CMB intensity maps: duel peak structure

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Chinese Journal of Astronomy and Astrophysics 2009年第3期9卷 302-306页

作者： Hao liu ti-pei li Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate School of Chinese Academy of Sciences Beijing 100039 China Department of Physics ＆ Center for Astrophysics Tsinghua University Beijing 100084 China Department of Engineering Physics ＆ Center for Astrophysics Tsinghua University Beijing100084 China

We study the local structure of Cosmic Microwave Background （CMB） temperature maps released by the Wilkinson Microwave Anisotropy Probe （WMAP） team, and find a new kind of structure, which can be described as follows： a peak （or valley） of average temperature is often followed by a peak of temperature fluctuation that is 4° away. This structure is important for the following reasons： both the well known cold spot detected by Cruz et al. and the hot spot detected by Vielva et al. with the same technology （the third spot in their article） have such structure; more spots that are similar to them can be found on CMB maps and they also tend to be significant cold/hot spots; if we change the 4° characteristic into an artificial one, such as 3° or 5°, there will be less ＂similar spots＂, and the temperature peaks or valleys will be less significant. The presented ＂sim- ilar spots＂ have passed a strict consistency test which requires them to be significant on at least three different CMB temperature maps. We hope that this article could arouse some interest in the relationship of average temperature with temperature fluctuation in local areas; meanwhile, we are also trying to find an explanation for it which might be important to CMB observation and theory.

关键词： cosmic microwave background -- cosmology observations - methods data analysis

Evolution of dark energy–dark matter-coupled expanding universe

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Chinese Science Bulletin 2014年第33期59卷 4473-4477页

作者： ti-pei li Mei Wu Department of Physics Center for Astrophysics Tsinghua University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences

The present universe is dominated by repulsive dark energy. It is natural that the coupling between the dark energy and the attractive gravity has to be taken into account in studying the evolution of our universe. Here, we induce an evolution equation for dark energy–dark mattercoupled universe. The solutions of the dynamic equation provide a specific picture of cosmic evolution, which is well compatible with current observed evolution histories of both Hubble parameter and equation of state parameter of dark energy. In this picture, the already observed universe has undergone through three epochs—the epoch of equilibrium between gravity and dark energy at cosmological redshifts z [ 1, the phase transition epoch at z between about 0.5 and 1, and the present acceleration epoch starting from z ' 0:5. The expected matter-dominated deceleration epoch has not been seen yet, which requires future deep observations to look back upon more early universe.

关键词：膨胀宇宙暗能量耦合暗物质演变演化方程动力学方程吸引力

An unusual timing and spectral state of a black hole microquasar XTE J1550-564

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Chinese Journal of Astronomy and Astrophysics 2009年第2期9卷 179-190页

作者： Ying-Kang Jin Shuang-Nan Zhang ti-pei li Department of Engineering Physics and Center for Astrophysics Tsinghua University Beijing 100084 China Department of Physics and Center for Astrophysics Tsinghua University Beijing 100084 China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

An unusual timing and spectral state of a black hole microquasar XTE J1550- 564 observed with RXTE is analyzed. Millisecond variabilities are found, which are significantly shorter than the minimum possible time scale in the light curves of black hole binaries, as suggested by Sunyaev ＆ Revnivtsev （2000）. The X-ray spectral fitting result indicates that there is an unusual soft component in the spectrum, which may be responsible for the millisecond variabilities. The millisecond variabilities as well as the unusual soft spectral component should be produced from some small, but independent active regions in the accretion disk.

关键词： methods data analysis -- X-rays binaries -- X-rays individual (XTEJ1550-564)

timing in the time Domain: Cygnus X-1

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Chinese Journal of Astronomy and Astrophysics 2001年第4期1卷 313-332页

作者： ti-pei li (Department of Physics and Center for Astrophysics, Tsinghua University, Beijing 100084 High Energy Astrophysics Lab., Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039)E-mail:litp@*** Department of Physics and Center for Astrophysics Tsinghua University Beijing 100084 High Energy Astrophysics Lab. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039

Quantities characterizing temporal property, e.g., power density, coherence, and time lag, can be defined and calculated directly in the time domain without using the Fourier transformation. Spectral hardness, variability duration, and correlation between different characteristic quamtities on different time scale can be studied in the time domain as well. The temporal analysis technique in the time domain is a powerful tool, particularly in studying rapid variability on short time scales (or in high frequencies). Results of studying variabilities of X-rays from Cyg X-1 with the analysis technique in the time domain and RXTE data reveal valuable clues to understanding production and propagation processes of X-rays and structure of accretion disk in the black hole system.

关键词： methods: data analysis - stars: individual (Cygnus X-1) - X-rays: stars

Uniqueness Problem for the Backward Differential Equation of a Continuous-State Branching Process

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1825-1836页

作者： pei Sen li Zeng Hu li School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100872P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

The distributional properties of a multi-dimensional continuous-state branching process are determined by its cumulant semigroup,which is defined by the backward differential *** provide a proof of the assertion of Rhyzhov and Skorokhod(Theory ***.,1970)on the uniqueness of the solutions to the equation,which is based on a characterization of the process as the pathwise unique solution to a system of stochastic equations.

关键词： Continuous-state branching process multi-dimensional backward differential equation stochastic equation generator

Post-transcriptional regulation of DEAD-box RNA helicases in hematopoietic malignancies

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Genes & Diseases 2024年第5期11卷 315-323页

作者： Jiankun Fan Zhigang li li pei Yu Hou Institute of life Sciences Chongqing Medical UniversityChongqing 400016China Department of Hematology Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China

Hematopoiesis represents a meticulously regulated and dynamic biological *** aberrations affecting blood cells,induced by various factors,frequently give rise to hematological *** instances are often accompanied by a multitude of abnormal post-transcriptional regulatory events,including RNA alternative splicing,RNA localization,RNA degradation,and ***,post-transcriptional regulation plays a pivotal role in preserving hematopoietic *** DEAD-Box RNA helicase genes emerge as crucial post-transcriptional regulatory factors,intricately involved in sustaining normal hematopoiesis through diverse mechanisms such as RNA alternative splicing,RNA modification,and ribosome *** review consolidates the existing knowledge on the role of DEAD-box RNA helicases in regulating normal hematopoiesis and underscores the pathogenicity of mutant DEADBox RNA helicases in malignant *** is placed on elucidating both the positive and negative contributions of DEAD-box RNA helicases within the hematopoietic system.

关键词： DEAD-box RNA helicase Hemopoietic system Post-transcriptional regulation Ribosomes assembly RNA alternative splicing

Nano metal-photosensitizer based on Aza-BODIPY-Cu complex for CDT-enhanced dual phototherapy

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Chinese Chemical Letters 2024年第7期35卷 296-300页

作者： Wenjuan Jin Zelong Chen Yi Wang Jiaxuan li Jiahui li Yuxin pei Zhichao pei College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China

Chemodynamic therapy(CDT)combined with dual phototherapy(photothermal therapy(PTT)and photodynamic therapy(PDT))is an efficient way to synergistically improve anti-tumor ***,the combination of multiple modes often makes the composition of the system more complex,which is not conducive to clinical *** this study,a dual phototherapy ligand carboxyl-modified Aza-BODIPY(BOD-COOH)and metal active center Cu^(2+)were used to construct multiple-modes metalphotosensitizer nanoparticles(BOD-Cu NPs)via one-step coordination self-assembly for combination therapy of CDT/PDT/*** order to improve delivery efficiency,the targeted hydrophilic molecule pyridinemodified glucose derivative(G-Py)was synthesized and coated onto the BOD-Cu NPs to form a glycosylated nano metal-photosensitizer BOD-Cu@G by electrostatic *** Cu^(2+)in BOD-Cu@G could not only be used as a coordination node for metal-driven self-assembly but also consume intracellular glutathione(GSH),and then catalyze Fenton-like reaction to generate hydroxyl radical(·OH)for *** vitro and in vivo studies revealed that BOD-Cu@G could achieve excellent anti-tumor efficiency by CDTenhanced dual phototherapy.

关键词： Nano metal-photosensitizer Aza-BODIPY-Cu Coordination self-assembly Chemodynamic therapy Dual phototherapy

mRNA vaccine technology for infectious diseases and beyond

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Science China(life Sciences) 2024年第10期67卷 2267-2270页

作者： pei Hao Xiao li Xuan li Wu Zhong Key Laboratory of Molecular Virology and Immunology Shanghai Institute of Immunity and InfectionChinese Academy of SciencesShanghai 200031China Changchun Veterinary Research Institute Chinese Academy of Agricultural SciencesChangchun 130122China Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China National Engineering Research Center for the Emergency Drug Beijing Institute of Pharmacology and ToxicologyBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The rise of mRNA vaccine technology Vaccines stand as one of the most significant medical advancements,playing a crucial role in the prevention of infectious diseases and the improvement of global *** triumph of smallpox vaccination stands as a towering achievement in the annals of healthcare,leading to the complete elimination of a oncedevastating disease and showcasing the efficacy of vaccination methods.

关键词： methods vaccination prevention

Spacelike Framed Curves with lightlike Components and Singularities of Their Evolutes and Focal Surfaces in Minkowski 3-space

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1521-1532页

作者： Peng Cheng li Dong He pei Xin ZHAO School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of Mathematics Harbin Institute of TechnologyWeihai 264209P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski *** is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike ***,we show a new geometric invariant to characterise singularities of the focal ***,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关键词： Evolutes focal surfaces spacelike framed curves singularities