Results 91 to 100 of about 131,499 (275)

On the Integrability of the SIR Epidemic Model with Vital Dynamics

Advances in Mathematical Physics, 2020
In this paper, we study the SIR epidemic model with vital dynamics Ṡ=−βSI+μN−S,İ=βSI−γ+μI,Ṙ=γI−μR, from the point of view of integrability. In the case of the death/birth rate μ=0, the SIR model is integrable, and we provide its general solutions by ...
Ding Chen
doaj   +1 more source

The physics and the mixed Hodge structure of Feynman integrals [PDF]

, 2014
This expository text is an invitation to the relation between quantum field theory Feynman integrals and periods. We first describe the relation between the Feynman parametrization of loop amplitudes and world-line methods, by explaining that the first ...
Vanhove, Pierre
core   +1 more source

Counterion Dependent Side‐Chain Relaxation Stiffens a Chemically Doped Thienothiophene Copolymer

Advanced Functional Materials, EarlyView.
Oxidation of a thienothiophene copolymer, p(g3TT‐T2), via different doping strategies and dopant molecules resulted in materials with similar oxidation levels and a high electrical conductivity of ≈100 S cm−1. However, mechanical properties varied significantly, with sub‐glass transition temperatures and elastic moduli spanning from –44°C to –3°C and ...
Mariavittoria Craighero, Meghna Jha, Elsa Veronica Flores‐Vela, Joost Kimpel, Andreas Schaefer, Jiali Guo, Jesika Asatryan, Alberto Peinador Veiga, Shuichi Haraguchi, Per‐Anders Carlsson, Jaime Martín, Mariano Campoy‐Quiles, Christian Müller   +12 more
wiley   +1 more source

First integrals and phase portraits of planar polynomial differential cubic systems with invariant straight lines of total multiplicity eight

Electronic Journal of Qualitative Theory of Differential Equations, 2017
In the article [C. Bujac, J. Llibre, N. Vulpe, Qual. Theory Dyn. Syst. 15(2016), 327–348] for the family of cubic differential systems with the maximum number of invariant straight lines, i.e.
Cristina Bujac, Nicolae Vulpe
doaj   +1 more source

On the existence of polynomial first integrals of quadratic homogeneous systems of ordinary differential equations

, 2000
We consider systems of ordinary differential equations with quadratic homogeneous right hand side. We give a new simple proof of a result already obtained in [8,10] which gives the necessary conditions for the existence of polynomial first integrals. The
Tsygvintsev, Alexei
core   +4 more sources

Imaging of Biphoton States: Fundamentals and Applications

Advanced Functional Materials, EarlyView.
Quantum states of two photons exhibit a rich polarization and spatial structure, which provides a fundamental resource of strongly correlated and entangled states. This review analyzes the physics of these intriguing properties and explores the various techniques and technologies available to measure them, including the state of the art of their ...
Alessio D'Errico, Ebrahim Karimi
wiley   +1 more source

KdV hierarchies and quantum Novikov's equations [PDF]

Open Communications in Nonlinear Mathematical Physics
This paper begins with a review of the well-known KdV hierarchy, the $N$-th Novikov equation, and its finite hierarchy in the classical commutative case. This finite hierarchy consists of $N$ compatible integrable polynomial dynamical systems in $\mathbb{
V. M. Buchstaber, A. V. Mikhailov
doaj   +1 more source

Nucleation‐Controlled Reconstruction of CuOx for Selective CO2 Electroreduction

Advanced Functional Materials, EarlyView.
The ratio of oxygen vacancies (Ov) and exposed Cu2O (111)/(200) of CuOx precatalyst is modulated by nucleation control of Cu(OH)2 precursor. Low Ov ratio and high ratio of Cu2O (111)/(200) in slow‐nucleated CuOx reconstructs to high‐coordinated oxide‐derived copper (OD‐Cu) during electrochemical CO2 reduction reaction (CO2RR) and exhibits enhanced ...
Ying Ying Ch'ng, Zhipeng Ma, Ming Zhang, Shujie Zhou, Varun Kundi, Priyank Vijaya Kumar, Wenyu Zhong, Yuwei Yang, Jitraporn Vongsvivut, Qinfen Gu, Xiaoxuan Luo, Lixue Jiang, Rahman Daiyan, Zhaojun Han, Rose Amal   +14 more
wiley   +1 more source

Multiplex Modular Nanorobotic Systems with Catalytic Activity under Magnetic Navigation

Advanced Functional Materials, EarlyView.
We present modular nanorobots composed of a magnetic propulsion module and different extension modules carrying functional activities, assembled via DNA base pairing. The system integrates propulsion, optical tracking, enzymatic catalysis, and cell docking in a programmable manner.
Voichita Mihali, Xinan Huang, Lucie Motyckova, Nicolas Moreno Gomez, Michal Skowicki, Cora‐Ann Schoenenberger, Peer Fischer, Cornelia G. Palivan   +7 more
wiley   +1 more source

An Adaptive Pseudospectral Method for Fractional Order Boundary Value Problems

Abstract and Applied Analysis, 2012
An adaptive pseudospectral method is presented for solving a class of multiterm fractional boundary value problems (FBVP) which involve Caputo-type fractional derivatives. The multiterm FBVP is first converted into a singular Volterra integrodifferential
Mohammad Maleki, Ishak Hashim, Majid Tavassoli Kajani, Saeid Abbasbandy   +3 more
doaj   +1 more source