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Is Dark Matter Made up of Xons?

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Journal of Modern Physics 2013年第8期4卷 121-125页

作者： Jean-Paul Auffray ex courant institute of mathematical sciences New York University New York USA

Three months before his untimely death in Paris in July 1912, Henri Poincaré formulated the conjecture that Planck’s action element could (should) be regarded as constituting a “véritable atome”, i.e. an “atom of motion”, whose integrity arises from the fact that the “points” it contains are equivalent to one another from the standpoint of probability. In this paper we investigate the possibility that this conjecture provides a clue to the origin and nature of dark matter.

关键词： Smolin Poincaré Action Space Vacuum Scale Relativity Nottale Dark Matter Xons

Approximating the Gaussian as a Sum of exponentials and its Applications to the Fast Gauss Transform

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Communications in Computational Physics 2022年第1期31卷 1-26页

作者： Shidong Jiang Leslie Greengard Department of mathematical sciences New Jersey Institute of TechnologyNewarkNJ 07102USA courant institute of mathematical sciences New York UniversityNew YorkNY 10012USA Center for Computational Mathematics Flatiron InstituteSimons FoundationNew YorkNY 10010USA

We develop efficient and accurate sum-of-exponential(SOE)approximations for the Gaussian using rational approximation of the exponential function on the negative real *** digit accuracy can be obtained with eight terms and ten digit accuracy can be obtained with twelve *** representation is of potential interest in approximation theory but we focus here on its use in accelerating the fast Gauss transform(FGT)in one and two *** one-dimensional scheme is particularly straightforward and easy to implement,requiring only twenty-four lines of MATLAB *** two-dimensional version requires some care with data structures,but is significantly more efficient than existing *** a detailed presentation of the theoretical foundations,we demonstrate the performance of the fast transforms with several numerical experiments.

关键词： Fast Gauss transform sum-of-exponential approximation best rational approximation model reduction

The Faddeev knots as stable solitons: existence theorems

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Science China Mathematics 2004年第2期47卷 187-197页

作者： LIN Fanghua & YANG Yisongcourant institute of mathematical sciences, New York University, New York, New York 10012, U. S. A.School of Mathematics, institute for Advanced Study, Princeton, New Jersey 08540, U. S. A. Department of Mathematics, Polytechnic University, Brooklyn, New York 11201, U. S. A. courant institute of mathematical sciences New York University New York U S A School of Mathematics Institute for Advanced Study Princeton U S A Department of Mathematics Polytechnic University Brooklyn U S A

The problem of existence of knot-like solitons as the energy-minimizing configurations in the Faddeev model, topologically characterized by an Hopf invariant, Q, is considered. It is proved that, in the full space situation, there exists an infinite set S of integers so that for any m ∈ S, the Faddeev energy, E, has a minimizer among the class Q = m; in the bounded domain situation, the same existence theorem holds when S is the set of all integers. One of the important technical results is that E and Q satisfy the sublinear inequality E ≤ C|Q|3/4, where C > 0 is a universal constant, which explains why knotted (clustered soliton) configurations are preferred over widely separated unknotted (multisoliton) configurations when |Q| is sufficiently large.

关键词： knots, Hopf invariant, minimization, solitons.

<i>E</i>Infinity, the Zero Set, Absolute Space and the Photon Spin

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Journal of Modern Physics 2015年第5期6卷 536-545页

作者： Jean-Paul Auffray ex: courant institute of mathematical sciences New York University New York USA ex: American institute of Physics New York USA

As defined and used in General Relativity calculations, spacetime is a strictly classical construct which does not incorporate in any way, shape or form the concept of quantum. While reviewing the efforts that Alexandria theoretician M. S. El Naschie has made to resolve the dichotomy, we discovered that his E infinity theory contains a Cantor set which has characteristics specified by Isaac Newton for Absolute space. We show that this unexpected connection leads to an understanding of the mysterious origin of the one and only attribute that all particles listed in the Standard Model of Elementary Particles possess—including notably the photon—and which has remained unexplained hitherto: spin. This most rewarding result reinforces our belief in the relevance of the E infinity basic concepts in relation to our own Xonic Quantum Physics (XQP) which places dynamical action rather spacetime and energy at the core of the System of the World.

关键词： Quantum Foam E Infinity Xonic Quantum Physics Newton Absolute Space Photon Spin

Si-Miao-Yong-An Decoction alleviates thromboangiitis obliterans by regulating miR-548j-5p/IL-17A signaling pathway

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Chinese Journal of Natural Medicines 2024年第6期22卷 541-553页

作者： CHU Chu SUN Shangwen ZHANG Zhen WU Qi LI Haoyang LIANG Gang MIAO Xiuming JIANG Haiqiang GAO Yan ZHANG Yunhong WANG Bin LI Xia Innovative institute of Chinese Medicine and Pharmacy Shandong University of Traditional Chinese MedicineJinan 250355China National Key Laboratory for Innovation and Transformation of Luobing Theory The Key Laboratory of Cardiovascular Remod-eling and Function ResearchChinese Ministry of EducationChinese National Health Commission and Chinese Academy of Medical SciencesDepartment of CardiologyQilu Hospital of Shandong UniversityJinan 250012China School of Clinical and Basic Medical sciences Shandong First Medical University&Shandong Academy of Medical SciencesJinan 271016China Affiliated Hospital of Shandong University of Traditional Chinese Medicine Jinan 250014China International Business School Tianjin Foreign Studies UniversityTianjin 300204China institute of Pharmaceutical Research Shandong University of Traditional Chinese MedicineJinan 250355China

Thromboangiitis obliterans(TAO)is a rare,chronic,progressive,and segmental inflammatory disease characterized by a high rate of amputation,significantly compromising the quality of life of ***-Miao-Yong-An decoction(SMYA),a tradition-al prescription,exhibits anti-inflammatory,anti-thrombotic,and various other pharmacological ***,it was fully proved to be effective for TAO therapy,but the specific therapeutic effect of SMYA on TAO has been ***,deep unveiling the mechanism of SMYA in TAO for identifying clinical therapeutic targets is extremely *** this study,we observed elev-ated levels of IL-17A in the peripheral blood mononuclear cells(PBMCs)of TAO patients,whereas the expression of miR-548j-5p was significantly decreased.A negative correlation between the levels of miR-548j-5p and IL-17A was also *** vitro ex-periments showed that overexpression of miR-548j-5p led to a decrease in IL-17A levels,whereas downregulation of miR-548j-5p showed the opposite *** a dual luciferase assay,we confirmed that miR-548j-5p directly targets ***,serum containing SMYA effectively decreased IL-17A levels by increasing the expression of *** importantly,the results of in vivo tests indicated that SMYA mitigated the development of TAO by inhibiting IL-17A through the upregulation of miR-548j-5p in vascular *** conclusion,SMYA significantly enhances the expression of miR-548j-5p,thereby reducing the levels of the target gene IL-17A and alleviating *** research not only identifies novel targets and pathways for the clinical diagnosis and treatment of TAO but also advances the innovation in traditional Chinese medicine through the elucidation of the SMYA/miR-548j-5p/IL-17A regulatory axis in the pathogenesis of TAO.

关键词： Thromboangiitis obliterans IL-17A Inflammation miR-548j-5p Si-Miao-Yong-An Decoction

Polariton lasing in Mie-resonant perovskite nanocavity

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Opto-Electronic Advances 2024年第4期7卷 27-42页

作者： Mikhail A.Masharin Daria Khmelevskaia Valeriy I.Kondratiev Daria I.Markina Anton D.Utyushev Dmitriy M.Dolgintsev Alexey D.Dmitriev Vanik A.Shahnazaryan Anatoly P.Pushkarev Furkan Isik Ivan V.Iorsh Ivan A.Shelykh Hilmi V.Demir Anton K.Samusev Sergey V.Makarov UNAM-institute of Materials Science and Nanotechnology National Nanotechnology Research CenterDepartment of Electrical and Electronics EngineeringDepartment of PhysicsBilkent UniversityAnkara 06800Turkey ITMO University School of Physics and EngineeringSt.Petersburg 197101Russia Abrikosov Center for Theoretical Physics MIPTDolgoprudnyiMoscow Region 141701Russia LUMINOUS!Center of excellence for Semiconductor Lighting and Displays School of Electrical and Electronic EngineeringSchool of Physical and Mathematical SciencesSchool of Materials Science and EngineeringNanyang Technological UniversitySingapore 639798Singapore Department of Physics Engineering Physics and AstronomyQueen’s UniversityKingstonOntario K7L 3N6Canada Science institute University of IcelandDunhagi 3IS-107ReykjavikIceland experimentelle Physik 2 Technische Universität DortmundDortmund 44227Germany Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China

Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the *** of the main obstacles for the development of single-particle nanolasers with all three dimensions shorter than the emitting wavelength in the visible range is the high lasing thresholds and the resulting *** we ex-ploit exciton-polariton condensation and mirror-image Mie modes in a cuboid CsPbBr3 nanoparticle to achieve coherent emission at the visible wavelength of around 0.53μm from its ultra-small(≈0.007μm3 or≈λ3/20)semiconductor *** polaritonic nature of the emission from the nanocavity localized in all three dimensions is proven by direct com-parison with corresponding one-dimensional and two-dimensional waveguiding systems with similar material *** a deeply subwavelength nanolaser is enabled not only by the high values for exciton binding energy(≈35 meV),re-fractive index(>2.5 at low temperature),and luminescence quantum yield of CsPbBr3,but also by the optimization of po-laritons condensation on the Mie resonances with quality factors improved by the metallic ***,the key parameters for optimal lasing conditions are intermode free spectral range and phonons spectrum in CsPbBr3,which govern polaritons condensation *** chemically synthesized colloidal CsPbBr3 nanolasers can be potentially de-posited on arbitrary surfaces,which makes them a versatile tool for integration with various on-chip systems.

关键词： nanolaser perovskite polariton Mie resonance exciton-polariton

Effective Maxwell Equations from Time-dependent Density Functional Theory

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Acta Mathematica Sinica,English Series 2011年第2期27卷 339-368页

作者： Weinan E Jianfeng LU Xu YANG Department of Mathematics and Program in Applied and Computational Mathematics Princeton University Princeton NJ 08544 USA Beijing International Center for mathematical Research and School of mathematical sciences Peking University Beijing 100871 P. R. China Department of Mathematics Courant Institute of Mathematical Sciences New York University New York NY 10012 USA

The behavior of interacting electrons in a perfect crystal under macroscopic external electric and magnetic fields is studied. Effective Maxwell equations for the macroscopic electric and magnetic fields are derived starting from time-dependent density functional theory. Effective permittivity and permeability coefficients are obtained.

关键词： Time-dependent density functional theory Maxwell equations effective permittivity electromagnetic fields

(Ba,K)Fe_(2)As_(2)铁基超导多芯线材的晶间耦合强化与性能提高

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Science China Materials 2024年第1期67卷 301-310页

作者：郭文文姚超熊颢杨鹏涂畅马衍伟 Key Laboratory of Applied Superconductivity Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of sciences Beijing 100049China institute of Electrical Engineering and Advanced Electromagnetic Drive Technology Qilu ZhongkeJinan 250013China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

铁基超导材料在高场超导磁体领域具有很大的应用潜力,而研究具有高传输临界电流密度的多芯复合包套线材对于其实际应用至关重要.本研究基于粉末装管法,结合孔型轧制工艺和热等静压烧结工艺制备了多芯Cu/Ag复合包套(Ba,K)Fe_(2)As_(2)(Ba... 详细信息

铁基超导材料在高场超导磁体领域具有很大的应用潜力,而研究具有高传输临界电流密度的多芯复合包套线材对于其实际应用至关重要.本研究基于粉末装管法,结合孔型轧制工艺和热等静压烧结工艺制备了多芯Cu/Ag复合包套(Ba,K)Fe_(2)As_(2)(Ba-122)超导线材.通过对不同直径线材中Ba-122超导芯的质量密度、晶粒取向、晶粒尺寸、元素分布与线材的电流传输性能之间的关系进行系统研究,我们发现线径较小的样品中超导晶粒间的耦合得到了显著增强,其传输临界电流密度在4.2 K,10 T下达到3.3×10^(4)A cm^(-2),同时由于晶粒尺寸和超导芯丝的均匀性得到改善,其电流传输的一致性(n值)也获得有效提高.本研究为制备高性能、高度均匀的铁基超导多芯线材提供了一种可规模化的工艺路线,对促进铁基超导材料的高场强电应用有重要意义.

关键词：热等静压烧结孔型轧制晶粒取向临界电流密度晶粒间质量密度晶粒尺寸工艺路线

Surface-derived phosphate layer on NiFe-layered double hydroxide realizes stable seawater oxidation at the current density of 1 A·cm^(−2)

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Nano Research 2024年第7期17卷 5786-5794页

作者： Chaoxin Yang Zhengwei Cai Jie Liang Kai Dong Zixiao Li Hang Sun Shengjun Sun Dongdong Zheng Hui Zhang Yongsong Luo Yongchao Yao Yan Wang Yuchun Ren Qian Liu Luming Li Wei Chu Xuping Sun Bo Tang College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014China institute of Fundamental and Frontier sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Science and Environmental Studies Faculty of Liberal Arts and Social Sciencethe Education University of Hong KongHong Kong 999077China institute for Advanced Study Chengdu UniversityChengdu 610106China Laoshan Laboratory Qingdao 266237China

Seawater electrolysis,especially in coastlines,is widely considered as a sustainable way of making clean and high-purity H2 from renewable energy;however,the practical viability is challenged severely by the limited anode durability resulting from side reactions of chlorine ***,we report an effective Cl^(−) blocking barrier of NiFe-layer double hydroxide(NiFe-LDH)to harmful chlorine chemistry during alkaline seawater oxidation(ASO),a pre-formed surface-derived NiFe-phosphate(Pi)***,the PO_(4)^(3−)-enriched outer-layer is capable of physically and electrostatically inhibiting Cl−adsorption,which protects active Ni^(3+)sites during *** NiFe-LDH with the NiFe-Pi outer-layer(NiFe-LDH@NiFe-Pi)exhibits higher current densities(j)and lower overpotentials to afford 1 A·cm^(−2)(η1000 of 370 mV versusη1000 of 420 mV)than the NiFe-LDH in 1 M KOH+***,the NiFe-LDH@NiFe-Pi also demonstrates longer-term electrochemical durability than NiFe-LDH,attaining 100-h duration at the j of 1 A·cm^(−2).Additionally,the importance of surface-derived PO_(4)^(3−)-enriched outer-layer in protecting the active centers,γ-NiOOH,is explained by ex situ characterizations and in situ electrochemical spectroscopic studies.

关键词： seawater oxidation phosphate outer-layer layered double hydroxide electrostatic repulsion in situ Raman