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Uncovering Hidden Spin of Scalar Fields with Higher-Order Derivative Lagrangian:On the Wave Spin in Drifted and Dissipative Fields
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作者 Shuo Xin Mengxiang Xie Jie Ren 《Chinese Physics Letters》 2025年第6期70-77,共8页
Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand ... Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand elastic longitudinal waves,which are of irrotational curl-free nature without vorticity and can be describedby scalar fields.Moreover,the conventional theory cannot even answer the question of whether wave spin existsin dissipative fields,given the ubiquitous dissipation in reality.Here,to resolve the seeming paradox and answerthe challenging question,we uncover the origin of wave spin in scalar fields beyond traditional formalism byclarifying that the presence of higher-order derivatives in scalar field Lagrangians can give rise to non-vanishingwave spin.For“spinless”scalar fields of only first-order derivatives,we can make the hidden wave spin emergeby revealing a latent field that leads to the original field through a time derivative,thus giving higher-order termsin Lagrangian.Based on the standard Noether theorem approach,we exemplify the wave spin for unconventionaldrifted acoustic fields,and even for dissipative media,in scalar fields with higher-order derivative Lagrangian.The results would prompt people to build more comprehensive and fundamental understandings of structuralwave spin in classical fields. 展开更多
关键词 higher order derivative Lagrangian hidden spin acousticand elastic longitudinal waveswhich acoustic waves wave spin spin angular momentum scalar fields
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GFFD: Generalized free-form deformation with scalar fields 被引量:1
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作者 秦绪佳 华炜 +2 位作者 方向 鲍虎军 彭群生 《Journal of Zhejiang University Science》 EI CSCD 2003年第6期623-629,共7页
The novel free-form deformation (FFD) technique presented in the paper uses scalar fields definedby skeletons with arbitrary topology. The technique embeds objects into the scalar field by assigning a field value to e... The novel free-form deformation (FFD) technique presented in the paper uses scalar fields definedby skeletons with arbitrary topology. The technique embeds objects into the scalar field by assigning a field value to each point of the objects. When the space of the skeleton is changed, the distribution of the scalar field changes accordingly, which implicitly defines a deformation of the space. The generality of skeletons assures that the technique can freely define deformable regions to produce a broader range of shape deformations. 展开更多
关键词 FFD Computer aided geometric design(CAGD) Computer aided design(CAD) scalar field
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Dynamic of Scalar Bosons in Aharonov-Bohm Magnetic Field
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作者 Frédéric D. Y. Zongo 《Journal of Applied Mathematics and Physics》 2024年第1期268-276,共9页
We study the dynamic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the differential equation that governs this dynamic. Secondly, we use variational techniques to show that the follo... We study the dynamic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the differential equation that governs this dynamic. Secondly, we use variational techniques to show that the following Schrödinger-Newton equation: , where A is an Aharonov-Bohm magnetic potential, has a unique ground-state solution. 展开更多
关键词 scalar Boson Aharonov-Bohm Magnetic field Schrödinger-Newton Equation Ground-State Solution
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Novel Localized Excitations of Nonlinear Coupled Scalar Fields
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作者 LI Jin-Hua WU Huang-Jiao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1365-1372,共8页
Some extended solution mapping relations of the nonlinear coupled scalar field and the well-known φ^4 model are presented. Simultaneously, inspired by the new solutions of the famous φ^4 model recently proposed by J... Some extended solution mapping relations of the nonlinear coupled scalar field and the well-known φ^4 model are presented. Simultaneously, inspired by the new solutions of the famous φ^4 model recently proposed by Jia, Huang and Lou, five kinds of new localized excitations of the nonlinear coupled scaiar field (NCSF) system are obtained. 展开更多
关键词 nonlinear coupled scalar field solitary wave structure mapping and deformation approach
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Quantum Electrodynamics(QED)Driving Longitudinal Scalar Wave(LSW)Descriptions and Their Physics and Mathematical Equations
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作者 Bahman Zohuri Mehdi Abedi-Varaki 《Journal of Energy and Power Engineering》 2025年第2期45-53,共9页
QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interes... QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interest in the theoretical and experimental exploration of LSW(longitudinal scalar waves)solutions that are often omitted in CED(classical electrodynamics)but may have physical significance in nontrivial vacuum conditions.This paper delves into the theoretical foundation of LSW,their role in QED,and the associated mathematical equations governing their dynamics. 展开更多
关键词 QED LSW scalar fields Klein-Gordon equation QFT Feynman diagrams scalar bosons electromagnetic field interaction quantum mechanics Fourier transform
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Real scalar field scattering in the nearly extremal Schwarzschild de Sitter space 被引量:3
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作者 郭广海 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期140-143,共4页
Reasonable approximations are introduced to investigate the real scalar field scattering in the nearly extremal Schwarzschild-de Sitter (SdS) space. The approximations naturally lead to the invertible x(r) and the... Reasonable approximations are introduced to investigate the real scalar field scattering in the nearly extremal Schwarzschild-de Sitter (SdS) space. The approximations naturally lead to the invertible x(r) and the global replacement of the true potential by a PSshl-Teller one. Meanwhile, the Schr6dinger-like wave equation is transformed into a solvable form. Our numerical solutions to the wave equation show that the wave is characteristically similar to the harmonic under the tortoise coordinate x, while the wave piles up near the two horizons and the wavelength tends to its maximum as the potential approaches to the peak under the radial coordinate τ. 展开更多
关键词 scalar field Poshl-Teller potential near extremal SdS space
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Real scalar field scattering with polynomial approximation around Schwarzschild–de Sitter black-hole 被引量:2
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作者 刘墨林 刘宏亚 +1 位作者 张敬飞 于飞 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1633-1639,共7页
As one of the fitting methods, the polynomial approximation is effective to process sophisticated problem. In this paper, we employ this approach to handle the scattering of scalar field around the Schwarzschild-de Si... As one of the fitting methods, the polynomial approximation is effective to process sophisticated problem. In this paper, we employ this approach to handle the scattering of scalar field around the Schwarzschild-de Sitter blackhole. The complicated relationship between tortoise coordinate and radial coordinate is replaced by the approximate polynomial. The Schroedinger-like equation, the real boundary conditions and the polynomial approximation construct a full Sturm Liouville type problem. Then this boundary value problem can be solved numerically for two limiting cases: the first one is the Nariai black-hole whose horizons are close to each other, the second one is the black-hole with the horizons widely separated. Compared with previous results (Brevik and Tian), the field near the event horizon and cosmological horizon can have a better description. 展开更多
关键词 Hawking radiation scalar field polynomial approximation boundary conditions
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A CONDITIONAL RANDOM FIELDS APPROACH TO BIOMEDICAL NAMED ENTITY RECOGNITION 被引量:4
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作者 Wang Haochang Zhao Tiejun Li Sheng Yu Hao 《Journal of Electronics(China)》 2007年第6期838-844,共7页
Named entity recognition is a fundamental task in biomedical data mining. In this letter, a named entity recognition system based on CRFs (Conditional Random Fields) for biomedical texts is presented. The system mak... Named entity recognition is a fundamental task in biomedical data mining. In this letter, a named entity recognition system based on CRFs (Conditional Random Fields) for biomedical texts is presented. The system makes extensive use of a diverse set of features, including local features, full text features and external resource features. All features incorporated in this system are described in detail, and the impacts of different feature sets on the performance of the system are evaluated. In order to improve the performance of system, post-processing modules are exploited to deal with the abbreviation phenomena, cascaded named entity and boundary errors identification. Evaluation on this system proved that the feature selection has important impact on the system performance, and the post-processing explored has an important contribution on system performance to achieve better resuits. 展开更多
关键词 Conditional Random fields (CRFs) Named entity recognition Feature selection post-processing
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Finite Time Domain Dynamics of Scalar Fields
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作者 Emmanouil George Thrapsaniotis 《Journal of Applied Mathematics and Physics》 2025年第2期454-464,共11页
In the present paper, we study the finite time domain dynamics of a scalar field interacting with external sources. We expand both the scalar field and the corresponding Hamiltonian in annihilation and creation operat... In the present paper, we study the finite time domain dynamics of a scalar field interacting with external sources. We expand both the scalar field and the corresponding Hamiltonian in annihilation and creation operators and evaluate the relevant path integral. So, we get the Green function within a finite time interval. We apply the solution to the relevant Cauchy problem and further, we study the dynamics of scalar fields coupled with electromagnetic fields via perturbative methods. 展开更多
关键词 scalar fields Finite Time Evolution Electromagnetic field Perturbative Methods
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Effects of Interaction Between Gravitation and Nonlinear Electrodynamics On Scalar Field Evolution 被引量:1
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作者 陈菊华 王永久 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第5期813-816,共4页
In this paper we investigate the scalar field evolution in the dyadosphere spacetime by using the third-order WKB approximation. We find that the coupling term between the gravitation and the nonlinear electrodynamics... In this paper we investigate the scalar field evolution in the dyadosphere spacetime by using the third-order WKB approximation. We find that the coupling term between the gravitation and the nonlinear electrodynamics makes the scalar field decay more quickly and it also makes the scalar field oscillate more slowly. On the o'ther words, this coupling term takes effect on the scalar field evolution as a damping factor. At the same time these effects become more obvious for the scalar field with higher angle quantum number. 展开更多
关键词 scalar field nonlinear electrodynamics dyadosphere spacetime
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Reconstruction of Scalar Field Dark Energy Models in Kaluza-Klein Universe 被引量:1
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作者 M.Sharif Abdul Jawad 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第8期183-188,共6页
This paper is devoted to study the modified holographic dark energy model by taking its different aspects in the t/at Kaiuza-Klein universe. We construct the equation of state parameter which evolutes the universe fro... This paper is devoted to study the modified holographic dark energy model by taking its different aspects in the t/at Kaiuza-Klein universe. We construct the equation of state parameter which evolutes the universe from quintessence region towards the vacuum. It is found that the modified holographic model exhibits instability against small perturbations in the early epoch of the universe but becomes stable in the later times. We also develop its correspondence with some scalar field dark energy models. It is interesting to mention here that ail the results are consistent with the present observations. 展开更多
关键词 Kaluza-Klein cosmology modified holographic dark energy scalar field models
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Generalized Ghost Pilgrim Scalar Field Models of Dark Energy
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作者 Abdul Jawad Ujjal Debnath Fazal Batool 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第11期590-596,共7页
We assume generalized ghost Pilgrim dark energy(GGPDE) model in the presence of cold dark matter in flat FRW universe.With suitable choice of interaction term between GGPDE and cold dark matter,we investigate the natu... We assume generalized ghost Pilgrim dark energy(GGPDE) model in the presence of cold dark matter in flat FRW universe.With suitable choice of interaction term between GGPDE and cold dark matter,we investigate the nature of equation of state parameter for GGPDE.Also,we investigate the natures of dynamical scalar field models(such as quintessence,tachyon,k-essence,and dilaton dark energy) and concerned potentials through the correspondence phenomenon between GGPDE and these models. 展开更多
关键词 GENERALIZED GHOST PILGRIM DARK energy scalar field
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Weak cosmic censorship conjecture in the nonlinear electrodynamics black hole under the charged scalar field
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作者 Tianhao Bai Wei Hong +1 位作者 Benrong Mu Jun Tao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第1期89-95,共7页
In this paper,we study the thermodynamics and the weak cosmic censorship conjecture of the nonlinear electrodynamics black hole under the scattering of a charged complex scalar field.According to the energy and charge... In this paper,we study the thermodynamics and the weak cosmic censorship conjecture of the nonlinear electrodynamics black hole under the scattering of a charged complex scalar field.According to the energy and charge fluxes of the scalar field,the variations of this black hole’s energy and charge can be calculated during an infinitesimal time interval.With scalar field scattering,the variation of the black hole is calculated in the extended and normal phase spaces.In the normal phase space,the cosmological constant and the normalization parameter are fixed,and the first and second laws of thermodynamics can also be satisfied.In the extended phase space,the cosmological constant and the normalization parameter are considered as thermodynamic variables,and the first law of thermodynamics is valid,but the second law of thermodynamics is not valid.Furthermore,the weak cosmic censorship conjecture is both valid in the extended and normal phase spaces. 展开更多
关键词 nonlinear ELECTRODYNAMICS black hole WEAK COSMIC CENSORSHIP CONJECTURE complex scalar field thermodynamics
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Exact Static Plane Symmetric Soliton-Like Solutions to the Nonlinear Interacting Electromagnetic and Scalar Field Equations in General Relativity 被引量:1
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作者 Arnaud Edouard Yamadjako Alain Adomou +2 位作者 Yélomè J. F. Kpomahou Jonas Edou Siaka Massou 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第1期164-177,共14页
This research work is related to soliton solutions considered as models that can describe the complex configuration of elementary particles from the study of the interactions of their fields. It is interested in the i... This research work is related to soliton solutions considered as models that can describe the complex configuration of elementary particles from the study of the interactions of their fields. It is interested in the interaction of fields between two different elementary particles by expressing their physical properties. For that, we have obtained, exact static plane symmetric soliton-like solutions to the nonlinear equations of interacting electromagnetic and scalar fields taking into account the own gravitational field of elementary particles using the calibrated invariance function <i>P</i>(<i>I</i>). It has been proved that all solutions of the Einstein, nonlinear electromagnetic and scalar field equations are regular with the localized energy density. Moreover, the total charge of particles is finite and the total energy of the interaction fields is bounded. It have been emphasized the importance to the own gravitational field of elementary particles and the role of the nonlinearity of fields in the determination of these solutions. In flat space-time, soliton-like solutions exist but the total energy of the interaction fields is equal to zero. We have also shown that in the linear case, soliton-like solutions are absent. 展开更多
关键词 scalar ELECTROMAGNETIC Gravitational fields Interaction’s Description of Elementary Particles
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Resonant frequencies of massless scalar field in rotating black-brane spacetime
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作者 荆继良 潘启沅 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期1985-1989,共5页
This paper investigates the resonant frequencies of the massless scalar field in the near extremal Kerr-like black-brane spacetime. It is shown that the different angular quantum number will present different resonant... This paper investigates the resonant frequencies of the massless scalar field in the near extremal Kerr-like black-brane spacetime. It is shown that the different angular quantum number will present different resonant frequencies. It is also shown that the real part of the resonant frequencies increases as the compact dimensions parameter μi increases, but the magnitude of the imaginary part decreases as μi increases. 展开更多
关键词 resonant frequency black brane scalar field
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STUDY OF EXPLICIT ANALYTIC SOLUTIONS FOR THE NONLINEAR COUPLED SCALAR FIELD EQUATIONS
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作者 YAN Zhen-ya(闫振亚) +1 位作者 ZHANG Hong-qing(张鸿庆) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第6期637-641,共5页
By using two different transformations, several types of exact analytic solutions for a class of nonlinear coupled scalar field equation are obtained, which contain soliton solutions, singular solitary wave solutions ... By using two different transformations, several types of exact analytic solutions for a class of nonlinear coupled scalar field equation are obtained, which contain soliton solutions, singular solitary wave solutions and triangle function solutions. These results can be applied to other nonlinear equations. In addition, parts of conclusions in some references are corrected. 展开更多
关键词 nonlinear coupled scalar field equation analytic solution soliton solution periodic solution
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Interacting tachyonic scalar field
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作者 A Kundu S D Pathak V K Ojha 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第2期102-107,共6页
We discuss the coupling between dark energy and matter by considering a homogeneous tachyonic scalar field as a candidate for dark energy.We obtained the functional form of scale factor by assuming that the coupling s... We discuss the coupling between dark energy and matter by considering a homogeneous tachyonic scalar field as a candidate for dark energy.We obtained the functional form of scale factor by assuming that the coupling strength depends linearly on the Hubble parameter and energy density.We also estimated the cosmic age of the Universe for different values of coupling constant. 展开更多
关键词 dark energy dark matter scalar field achyonic scalar field
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A comparison of phantom linear scalar field and non-linear Born-Infeld scalar field
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作者 周建华 陆惠卿 +1 位作者 方伟 魏晨星 《Journal of Shanghai University(English Edition)》 CAS 2008年第5期405-409,共5页
This paper studies phantom linear scalar field (LSF) and phantom non-linear Born-Infeld (NLBI) scalar field with square potential of the form V(Ф) =1/2m^2Ф^2. The equation of state parameter w(z), and evolut... This paper studies phantom linear scalar field (LSF) and phantom non-linear Born-Infeld (NLBI) scalar field with square potential of the form V(Ф) =1/2m^2Ф^2. The equation of state parameter w(z), and evolution of scale factor a(t) in both phantom LSF and phantom NLBI scalar model are explored. The age of universe Hot and the transition redshift Z are obtained. The Gold data set of 157-SN-Ia is used to constrain parameters of the two models by numerical calculation. The phantom LSF is slightly better than the phantom NLBI type scalar field model for a large m. Although a smaller m corresponding to a slower rolling of field Ф better fits the observation data, the difference between phantom NLBI scalar field and phantom LSF is not distinct in this case. 展开更多
关键词 dark energy phantom non-linear Born-Infeld (NLBI) type scalar field phantom linear scalar field (LSF)
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Complex frequencies of a massless scalar field in loop quantum black hole spacetime
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作者 陈菊华 王永久 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期48-53,共6页
Recently, considerable progress has been made in understanding the early universe by loop quantum cosmology. Modesto et al. investigated the loop quantum black hole (LQBH)using improved semiclassical analysis and th... Recently, considerable progress has been made in understanding the early universe by loop quantum cosmology. Modesto et al. investigated the loop quantum black hole (LQBH)using improved semiclassical analysis and they found that the LQBH has two horizons, an event horizon and a Cauchy horizon, just like the Reissner-NordstrSm black hole. This paper focuses on the dynamical evolution of a massless scalar wave in the LQBH background. By investigating the relation between the complex frequencies of the massless scalar field and the LQBH parameters using the numerical method, we find that the polymeric parameter P makes the massless scalar field decay more quickly and makes the ground scalar wave oscillate slowly. However, the polymeric parameter P causes the frequency of the high harmonic massless scalar wave to shift according to its value. We also find that the loop quantum gravity area gap parameter a0 causes the massless scalar field to decay more slowly and makes the period of the massless scalar field wave become longer. In the complex ω plane, the frequency curves move counterclockwise when the polymeric parameter P increases and this spiral effect is more obvious for a higher harmonic scalar wave. 展开更多
关键词 complex frequencies massless scalar field loop quantum black hole spacetime
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<i>L<sub>p</sub></i>-Estimations of Vector Fields in Unbounded Domains
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作者 Alexey V. Kalinin Alla A. Tyukhtina Artem A. Zhidkov 《Applied Mathematics》 2012年第1期45-51,共7页
Some new estimations of scalar products of vector fields in unbounded domains are investigated. Lp-estimations for the vector fields were proved in special weighted functional spaces. The paper generalizes our earlier... Some new estimations of scalar products of vector fields in unbounded domains are investigated. Lp-estimations for the vector fields were proved in special weighted functional spaces. The paper generalizes our earlier results for bounded domains. Estimations for scalar products make it possible to investigate wide classes of mathematical physics problems in physically inhomogeneous domains. Such estimations allow studying issues of correctness for problems with non-smooth coefficients. The paper analyses solvability of stationary set of Maxwell equations in inhomogeneous unbounded domains based on the proved Lp-estimations. 展开更多
关键词 Estimations scalar Product Vector field Functional Spaces Maxwell Equations SOLVABILITY Inhomogeneous Domains
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