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Publications of Alexander A. Kiselev    :chronological  alphabetical  combined listing:

%% Papers Published   
@article{fds374493,
   Author = {Gong, Y and Kiselev, A},
   Title = {A simple reaction-diffusion system as a possible model for
             the origin of chemotaxis.},
   Journal = {Journal of biological dynamics},
   Volume = {17},
   Number = {1},
   Pages = {2260833},
   Year = {2023},
   Month = {December},
   url = {http://dx.doi.org/10.1080/17513758.2023.2260833},
   Abstract = {Chemotaxis is a directed cell movement in response to
             external chemical stimuli. In this paper, we propose a
             simple model for the origin of chemotaxis - namely how a
             directed movement in response to an external chemical signal
             may occur based on purely reaction-diffusion equations
             reflecting inner working of the cells. The model is inspired
             by the well-studied role of the rho-GTPase Cdc42 regulator
             of cell polarity, in particular in yeast cells. We analyse
             several versions of the model to better understand its
             analytic properties and prove global regularity in one and
             two dimensions. Using computer simulations, we demonstrate
             that in the framework of this model, at least in certain
             parameter regimes, the speed of the directed movement
             appears to be proportional to the size of the gradient of
             signalling chemical. This coincides with the form of the
             chemical drift in the most studied mean field model of
             chemotaxis, the Keller-Segel equation.},
   Doi = {10.1080/17513758.2023.2260833},
   Key = {fds374493}
}

@article{fds374494,
   Author = {Kiselev, A and Luo, X},
   Title = {Illposedness of C2 Vortex Patches},
   Journal = {Archive for Rational Mechanics and Analysis},
   Volume = {247},
   Number = {3},
   Year = {2023},
   Month = {June},
   url = {http://dx.doi.org/10.1007/s00205-023-01892-7},
   Abstract = {It is well known that vortex patches are wellposed in C1,α
             if 0 < α< 1 . In this paper, we prove the illposedness of
             C2 vortex patches. The setup is to consider the vortex
             patches in Sobolev spaces W2,p where the curvature of the
             boundary is Lp integrable. In this setting, we show the
             persistence of W2,p regularity when 1 < p< ∞ and construct
             C2 initial patch data for which the curvature of the patch
             boundary becomes unbounded immediately for t> 0 , though it
             regains C2 regularity precisely at all integer times without
             being time periodic. The key ingredient is the evolution
             equation for the curvature, the dominant term in which turns
             out to be linear and dispersive.},
   Doi = {10.1007/s00205-023-01892-7},
   Key = {fds374494}
}

@article{fds374495,
   Author = {Kiselev, A and Luo, X},
   Title = {On Nonexistence of Splash Singularities for the α -SQG
             Patches},
   Journal = {Journal of Nonlinear Science},
   Volume = {33},
   Number = {2},
   Year = {2023},
   Month = {April},
   url = {http://dx.doi.org/10.1007/s00332-023-09893-2},
   Abstract = {In this paper, we consider patch solutions to the α-SQG
             equation and derive new criteria for the absence of splash
             singularity where different patches or parts of the same
             patch collide in finite time. Our criterion refines a result
             due to Gancedo and Strain Gancedo and Strain (2014),
             providing a condition on the growth of curvature of the
             patch necessary for the splash and an exponential in time
             lower bound on the distance between patches with bounded
             curvature.},
   Doi = {10.1007/s00332-023-09893-2},
   Key = {fds374495}
}

@article{fds368885,
   Author = {Kiselev, A and Yao, Y},
   Title = {Small Scale Formations in the Incompressible Porous Media
             Equation},
   Journal = {Archive for Rational Mechanics and Analysis},
   Volume = {247},
   Number = {1},
   Year = {2023},
   Month = {February},
   url = {http://dx.doi.org/10.1007/s00205-022-01830-z},
   Abstract = {We construct examples of solutions to the incompressible
             porous media (IPM) equation that must exhibit infinite in
             time growth of derivatives provided they remain smooth. As
             an application, this allows us to obtain nonlinear
             instability for a class of stratified steady states of
             IPM.},
   Doi = {10.1007/s00205-022-01830-z},
   Key = {fds368885}
}

@article{fds374496,
   Author = {Kiselev, A and Nazarov, F and Ryzhik, L and Yao, Y},
   Title = {Chemotaxis and reactions in biology},
   Journal = {Journal of the European Mathematical Society},
   Volume = {25},
   Number = {7},
   Pages = {2641-2696},
   Year = {2023},
   Month = {January},
   url = {http://dx.doi.org/10.4171/JEMS/1247},
   Abstract = {Chemotaxis plays a crucial role in a variety of processes in
             biology and ecology. Quite often it acts to improve
             efficiency of biological reactions. One example is the
             immune system signalling, where infected tissues release
             chemokines attracting monocytes to fight invading bacteria.
             Another example is reproduction, where eggs release
             pheromones that attract sperm. A macro scale example is
             flower scent appealing to pollinators. In this paper we
             consider a system of PDEs designed to model such processes.
             Our interest is to quantify the effect of chemotaxis on
             reaction rates compared to pure reaction-diffusion. We limit
             consideration to surface chemotaxis, which is well motivated
             from the point of view of many applications. Our results
             provide the first insight into situations where chemotaxis
             can be crucial for reaction success, and where its effect is
             likely to be limited. The proofs are based on new analytical
             tools; a significant part of the paper is dedicated to
             building up the linear machinery that can be useful in more
             general settings. In particular, we establish precise
             estimates on the rates of convergence to the ground state
             for a class of Fokker–Planck operators with potentials
             that grow at a logarithmic rate at infinity. These estimates
             are made possible by a new sharp weak weighted Poincaré
             inequality.},
   Doi = {10.4171/JEMS/1247},
   Key = {fds374496}
}

@article{fds366478,
   Author = {Kiselev, A and Tan, C},
   Title = {The Flow of Polynomial Roots Under Differentiation},
   Journal = {Annals of PDE},
   Volume = {8},
   Number = {2},
   Year = {2022},
   Month = {December},
   url = {http://dx.doi.org/10.1007/s40818-022-00135-4},
   Abstract = {The question about behavior of gaps between zeros of
             polynomials under differentiation is classical and goes back
             to Marcel Riesz. Recently, Stefan Steinerberger [42]
             formally derived a nonlocal nonlinear partial differential
             equation which models dynamics of roots of polynomials under
             differentiation. In this paper, we connect rigorously
             solutions of Steinerberger’s PDE and evolution of roots
             under differentiation for a class of trigonometric
             polynomials. Namely, we prove that the distribution of the
             zeros of the derivatives of a polynomial and the
             corresponding solutions of the PDE remain close for all
             times. The global in time control follows from the analysis
             of the propagation of errors equation, which turns out to be
             a nonlinear fractional heat equation with the main term
             similar to the modulated discretized fractional Laplacian (-
             Δ) 1 / 2.},
   Doi = {10.1007/s40818-022-00135-4},
   Key = {fds366478}
}

@article{fds367156,
   Author = {Gong, Y and He, S and Kiselev, A},
   Title = {Random Search in Fluid Flow Aided by Chemotaxis.},
   Journal = {Bulletin of mathematical biology},
   Volume = {84},
   Number = {7},
   Pages = {71},
   Year = {2022},
   Month = {June},
   url = {http://dx.doi.org/10.1007/s11538-022-01024-4},
   Abstract = {In this paper, we consider the dynamics of a 2D
             target-searching agent performing Brownian motion under the
             influence of fluid shear flow and chemical attraction. The
             analysis is motivated by numerous situations in biology
             where these effects are present, such as broadcast spawning
             of marine animals and other reproduction processes or
             workings of the immune systems. We rigorously characterize
             the limit of the expected hit time in the large flow
             amplitude limit as corresponding to the effective
             one-dimensional problem. We also perform numerical
             computations to characterize the finer properties of the
             expected duration of the search. The numerical experiments
             show many interesting features of the process and in
             particular existence of the optimal value of the shear flow
             that minimizes the expected target hit time and outperforms
             the large flow limit.},
   Doi = {10.1007/s11538-022-01024-4},
   Key = {fds367156}
}

@article{fds368303,
   Author = {Chouliara, D and Gong, Y and He, S and Kiselev, A and Lim, J and Melikechi,
             O and Powers, K},
   Title = {Hitting time of Brownian motion subject to shear
             flow},
   Journal = {Involve},
   Volume = {15},
   Number = {1},
   Pages = {131-140},
   Year = {2022},
   Month = {January},
   url = {http://dx.doi.org/10.2140/involve.2022.15.131},
   Abstract = {The 2-dimensional motion of a particle subject to Brownian
             motion and ambient shear flow transportation is considered.
             Numerical experiments are carried out to explore the
             relation between the shear strength, box size, and the
             particle’s expected first hitting time of a given target.
             The simulation is motivated by biological settings such as
             reproduction processes and the workings of the immune
             system. As the shear strength grows, the expected first
             hitting time converges to the expected first hitting time of
             the 1-dimensional Brownian motion. The dependence of the
             hitting time on the shearing rate is monotone, and only the
             form of the shear flow close to the target appears to play a
             role. Numerical experiments also show that the expected
             hitting time drops significantly even for quite small values
             of shear rate near the target.},
   Doi = {10.2140/involve.2022.15.131},
   Key = {fds368303}
}

@article{fds368304,
   Author = {Kiselev, A and Tan, C},
   Title = {GLOBAL REGULARITY FOR A NONLOCAL PDE DESCRIBING EVOLUTION OF
             POLYNOMIAL ROOTS UNDER DIFFERENTIATION},
   Journal = {SIAM Journal on Mathematical Analysis},
   Volume = {54},
   Number = {3},
   Pages = {3161-3191},
   Year = {2022},
   Month = {January},
   url = {http://dx.doi.org/10.1137/21M1422859},
   Abstract = {In this paper, we analyze a nonlocal nonlinear partial
             differential equation formally derived by Steinerberger
             [Proc. Amer. Math. Soc., 147 (2019), pp. 4733-4744] to model
             dynamics of roots of polynomials under differentiation. This
             partial differential equation is critical and bears striking
             resemblance to hydrodynamic models used to describe
             collective behavior of agents (such as birds, fish, or
             robots) in mathematical biology. We consider a periodic
             setting and show global regularity and exponential in time
             convergence to uniform density for solutions corresponding
             to strictly positive smooth initial data.},
   Doi = {10.1137/21M1422859},
   Key = {fds368304}
}

@article{fds361462,
   Author = {Kiselev, A and Luo, X},
   Title = {On nonexistence of splash singularities for the $α$-SQG
             patches},
   Year = {2021},
   Month = {November},
   Abstract = {In this paper, we consider patch solutions to the
             $\alpha$-SQG equation and derive new criteria for the
             absence of splash singularity where different patches or
             parts of the same patch collide in finite time. Our
             criterion refines a result due to Gancedo and Strain
             \cite{GS}, providing a condition on the growth of curvature
             of the patch necessary for the splash and an exponential in
             time lower bound on the distance between patches with
             bounded curvature.},
   Key = {fds361462}
}

@article{fds358295,
   Author = {He, S and Kiselev, A},
   Title = {Boundary layer models of the Hou-Luo scenario},
   Journal = {Journal of Differential Equations},
   Volume = {298},
   Pages = {182-204},
   Year = {2021},
   Month = {October},
   url = {http://dx.doi.org/10.1016/j.jde.2021.07.007},
   Abstract = {Finite time blow up vs global regularity question for 3D
             Euler equation of fluid mechanics is a major open problem.
             Several years ago, Luo and Hou [16] proposed a new finite
             time blow up scenario based on extensive numerical
             simulations. The scenario is axi-symmetric and features fast
             growth of vorticity near a ring of hyperbolic points of the
             flow located at the boundary of a cylinder containing the
             fluid. An important role is played by a small boundary layer
             where intense growth is observed. Several simplified models
             of the scenario have been considered, all leading to finite
             time blow up [3,2,9,13,11,15]. In this paper, we propose two
             models that are designed specifically to gain insight in the
             evolution of fluid near the hyperbolic stagnation point of
             the flow located at the boundary. One model focuses on
             analysis of the depletion of nonlinearity effect present in
             the problem. Solutions to this model are shown to be
             globally regular. The second model can be seen as an attempt
             to capture the velocity field near the boundary to the next
             order of accuracy compared with the one-dimensional models
             such as [3,2]. Solutions to this model blow up in finite
             time.},
   Doi = {10.1016/j.jde.2021.07.007},
   Key = {fds358295}
}

@article{fds361650,
   Author = {Gong, Y and He, S and Kiselev, A},
   Title = {Random search in fluid flow aided by chemotaxis},
   Year = {2021},
   Month = {July},
   Abstract = {In this paper, we consider the dynamics of a 2D
             target-searching agent performing Brownian motion under the
             influence of fluid shear flow and chemical attraction. The
             analysis is motivated by numerous situations in biology
             where these effects are present, such as broadcast spawning
             of marine animals and other reproduction processes or
             workings of the immune systems. We rigorously characterize
             the limit of the expected hit time in the large flow
             amplitude limit as corresponding to the effective
             one-dimensional problem. We also perform numerical
             computations to characterize the finer properties of the
             expected duration of the search. The numerical experiments
             show many interesting features of the process, and in
             particular existence of the optimal value of the shear flow
             that minimizes the expected target hit time and outperforms
             the large flow limit.},
   Key = {fds361650}
}

@article{fds361651,
   Author = {Gong, Y and Kiselev, A},
   Title = {Chemotactic Reaction Enhancement in One Dimension},
   Year = {2021},
   Month = {March},
   Abstract = {Chemotaxis, the directional locomotion of cells towards a
             source of a chemical gradient, is an integral part of many
             biological processes - for example, bacteria motion,
             single-cell or multicellular organisms development, immune
             response, etc. Chemotaxis directs bacteria's movement to
             find food (e.g., glucose) by swimming toward the highest
             concentration of food molecules. In multicellular organisms,
             chemotaxis is critical to early development (e.g., movement
             of sperm towards the egg during fertilization). Chemotaxis
             also helps mobilize phagocytic and immune cells at sites of
             infection, tissue injury, and thus facilitates immune
             reactions. In this paper, we study a PDE system that
             describes such biological processes in one dimension, which
             may correspond to a thin channel, the setting relevant in
             many applications: for example, spermatozoa progression to
             the ovum inside a Fallopian tube or immune response in a
             blood vessel.},
   Key = {fds361651}
}

@article{fds361348,
   Author = {Kiselev, A and Yao, Y},
   Title = {Small scale formations in the incompressible porous media
             equation},
   Year = {2021},
   Month = {February},
   Abstract = {We construct examples of solutions to the incompressible
             porous media (IPM) equation that must exhibit infinite in
             time growth of derivatives provided they remain smooth. As
             an application, this allows us to obtain nonlinear
             instability for a class of stratified steady states of
             IPM.},
   Key = {fds361348}
}

@article{fds356022,
   Author = {He, S and Kiselev, A},
   Title = {Small-scale creation for solutions of the sqg
             equation},
   Journal = {Duke Mathematical Journal},
   Volume = {170},
   Number = {5},
   Pages = {1027-1041},
   Publisher = {Duke University Press},
   Year = {2021},
   Month = {January},
   url = {http://dx.doi.org/10.1215/00127094-2020-0064},
   Abstract = {We construct examples of solutions to the conservative
             surface quasigeostrophic (SQG) equation that must either
             exhibit infinite-in-Time growth of derivatives or blow up in
             finite time.},
   Doi = {10.1215/00127094-2020-0064},
   Key = {fds356022}
}

@article{fds361594,
   Author = {Kiselev, A and Tan, C},
   Title = {The Flow of Polynomial Roots Under Differentiation},
   Year = {2020},
   Month = {December},
   Abstract = {The question about the behavior of gaps between zeros of
             polynomials under differentiation is classical and goes back
             to Marcel Riesz. In this paper, we analyze a nonlocal
             nonlinear partial differential equation formally derived by
             Stefan Steinerberger to model dynamics of roots of
             polynomials under differentiation. Interestingly, the same
             equation has also been recently obtained formally by Dimitri
             Shlyakhtenko and Terence Tao as the evolution equation for
             free fractional convolution of a measure - an object in free
             probability that is also related to minor processes for
             random matrices. The partial differential equation bears
             striking resemblance to hydrodynamic models used to describe
             the collective behavior of agents (such as birds, fish or
             robots) in mathematical biology. We consider periodic
             setting and show global regularity and exponential in time
             convergence to uniform density for solutions corresponding
             to strictly positive smooth initial data. In the second part
             of the paper we connect rigorously solutions of the
             Steinerberger's PDE and evolution of roots under
             differentiation for a class of trigonometric polynomials.
             Namely, we prove that the distribution of the zeros of the
             derivatives of a polynomial and the corresponding solutions
             of the PDE remain close for all times. The global in time
             control follows from the analysis of the propagation of
             errors equation, which turns out to be a nonlinear
             fractional heat equation with the main term similar to the
             modulated discretized fractional Laplacian
             $(-\Delta)^{1/2}$.},
   Key = {fds361594}
}

@article{fds361463,
   Author = {Kiselev, A and Nazarov, F and Ryzhik, L and Yao, Y},
   Title = {Chemotaxis and Reactions in Biology},
   Year = {2020},
   Month = {April},
   Abstract = {Chemotaxis plays a crucial role in a variety of processes in
             biology and ecology. Quite often it acts to improve
             efficiency of biological reactions. One example is the
             immune system signalling, where infected tissues release
             chemokines attracting monocytes to fight invading bacteria.
             Another example is reproduction, where eggs release
             pheromones that attract sperm. A macro scale example is
             flower scent appealing to pollinators. In this paper we
             consider a system of PDE designed to model such processes.
             Our interest is to quantify the effect of chemotaxis on
             reaction rates compared to pure reaction-diffusion. We limit
             consideration to surface chemotaxis, which is well motivated
             from the point of view of many applications. Our results
             provide the first insight into situations where chemotaxis
             can be crucial for reaction success, and where its effect is
             likely to be limited. The proofs are based on new analytical
             tools; a significant part of the paper is dedicated to
             building up the linear machinery that can be useful in more
             general settings. In particular we establish precise
             estimates on the rates of convergence to ground state for a
             class of Fokker-Planck operators with potentials that grow
             at a logarithmic rate at infinity. These estimates are made
             possible by a new sharp weak weighted Poincar\'e inequality
             improving in particular a result of Bobkov and
             Ledoux.},
   Key = {fds361463}
}

@article{fds376401,
   Author = {Kiselev, AA},
   Title = {Small Scale Creation in Active Scalars},
   Volume = {2272},
   Pages = {125-161},
   Booktitle = {Lecture Notes in Mathematics},
   Year = {2020},
   Month = {January},
   url = {http://dx.doi.org/10.1007/978-3-030-54899-5_4},
   Abstract = {The focus of the course is on small scale formation in
             solutions of the incompressible Euler equation of fluid
             dynamics and associated models. We first review the
             regularity results and examples of small scale growth in two
             dimensions. Then we discuss a specific singular scenario for
             the three-dimensional Euler equation discovered by Hou and
             Luo, and analyze some associated models. Finally, we will
             also talk about the surface quasi-geostrophic (SQG)
             equation, and construct an example of singularity formation
             in the modified SQG patch solutions as well as examples of
             unbounded growth of derivatives for the smooth
             solutions.},
   Doi = {10.1007/978-3-030-54899-5_4},
   Key = {fds376401}
}

@article{fds357911,
   Author = {Kiselev, AA},
   Title = {Small Scale Creation in Active Scalars},
   Journal = {PROGRESS IN MATHEMATICAL FLUID DYNAMICS},
   Volume = {2272},
   Pages = {123-159},
   Booktitle = {Lecture Notes in Mathematics},
   Year = {2020},
   ISBN = {978-3-030-54898-8},
   url = {http://dx.doi.org/10.1007/978-3-030-54899-5_4},
   Abstract = {The focus of the course is on small scale formation in
             solutions of the incompressible Euler equation of fluid
             dynamics and associated models. We first review the
             regularity results and examples of small scale growth in two
             dimensions. Then we discuss a specific singular scenario for
             the three-dimensional Euler equation discovered by Hou and
             Luo, and analyze some associated models. Finally, we will
             also talk about the surface quasi-geostrophic (SQG)
             equation, and construct an example of singularity formation
             in the modified SQG patch solutions as well as examples of
             unbounded growth of derivatives for the smooth
             solutions.},
   Doi = {10.1007/978-3-030-54899-5_4},
   Key = {fds357911}
}

@article{fds341002,
   Author = {Kiselev, A and Li, C},
   Title = {Global regularity and fast small-scale formation for Euler
             patch equation in a smooth domain},
   Journal = {Communications in Partial Differential Equations},
   Volume = {44},
   Number = {4},
   Pages = {279-308},
   Year = {2019},
   Month = {April},
   url = {http://dx.doi.org/10.1080/03605302.2018.1546318},
   Abstract = {It is well known that the Euler vortex patch in R 2 will
             remain regular if it is regular enough initially. In bounded
             domains, the regularity theory for patch solutions is less
             complete. In this article, we study Euler vortex patches in
             a general smooth bounded domain. We prove global in time
             regularity by providing an upper bound on the growth of
             curvature of the patch boundary. For a special symmetric
             scenario, we construct an example of double exponential
             curvature growth, showing that our upper bound is
             qualitatively sharp.},
   Doi = {10.1080/03605302.2018.1546318},
   Key = {fds341002}
}

@article{fds340353,
   Author = {Do, T and Kiselev, A and Xu, X},
   Title = {Stability of Blowup for a 1D Model of Axisymmetric 3D Euler
             Equation},
   Journal = {Journal of Nonlinear Science},
   Volume = {28},
   Number = {6},
   Pages = {2127-2152},
   Publisher = {Springer Nature America, Inc},
   Year = {2018},
   Month = {December},
   url = {http://dx.doi.org/10.1007/s00332-016-9340-7},
   Abstract = {The question of the global regularity versus finite- time
             blowup in solutions of the 3D incompressible Euler equation
             is a major open problem of modern applied analysis. In this
             paper, we study a class of one-dimensional models of the
             axisymmetric hyperbolic boundary blow-up scenario for the 3D
             Euler equation proposed by Hou and Luo (Multiscale Model
             Simul 12:1722–1776, 2014) based on extensive numerical
             simulations. These models generalize the 1D Hou–Luo model
             suggested in Hou and Luo Luo and Hou (2014), for which
             finite-time blowup has been established in Choi et al.
             (arXiv preprint. arXiv:1407.4776, 2014). The main new
             aspects of this work are twofold. First, we establish
             finite-time blowup for a model that is a closer
             approximation of the three-dimensional case than the
             original Hou–Luo model, in the sense that it contains
             relevant lower-order terms in the Biot–Savart law that
             have been discarded in Hou and Luo Choi et al. (2014).
             Secondly, we show that the blow-up mechanism is quite
             robust, by considering a broader family of models with the
             same main term as in the Hou–Luo model. Such blow-up
             stability result may be useful in further work on
             understanding the 3D hyperbolic blow-up scenario.},
   Doi = {10.1007/s00332-016-9340-7},
   Key = {fds340353}
}

@article{fds340371,
   Author = {Kiselev, A},
   Title = {Special Issue Editorial: Small Scales and Singularity
             Formation in Fluid Dynamics},
   Journal = {Journal of Nonlinear Science},
   Volume = {28},
   Number = {6},
   Pages = {2047-2050},
   Publisher = {Springer Nature America, Inc},
   Year = {2018},
   Month = {December},
   url = {http://dx.doi.org/10.1007/s00332-018-9452-3},
   Doi = {10.1007/s00332-018-9452-3},
   Key = {fds340371}
}

@article{fds335539,
   Author = {Do, T and Kiselev, A and Ryzhik, L and Tan, C},
   Title = {Global Regularity for the Fractional Euler Alignment
             System},
   Journal = {Archive for Rational Mechanics and Analysis},
   Volume = {228},
   Number = {1},
   Pages = {1-37},
   Publisher = {Springer Nature},
   Year = {2018},
   Month = {April},
   url = {http://dx.doi.org/10.1007/s00205-017-1184-2},
   Abstract = {We study a pressureless Euler system with a non-linear
             density-dependent alignment term, originating in the
             Cucker–Smale swarming models. The alignment term is
             dissipative in the sense that it tends to equilibrate the
             velocities. Its density dependence is natural: the alignment
             rate increases in the areas of high density due to species
             discomfort. The diffusive term has the order of a fractional
             Laplacian (-∂xx)α/2,α∈(0,1). The corresponding Burgers
             equation with a linear dissipation of this type develops
             shocks in a finite time. We show that the alignment
             nonlinearity enhances the dissipation, and the solutions are
             globally regular for all α∈ (0 , 1). To the best of our
             knowledge, this is the first example of such regularization
             due to the non-local nonlinear modulation of
             dissipation.},
   Doi = {10.1007/s00205-017-1184-2},
   Key = {fds335539}
}

@article{fds330278,
   Author = {Kiselev, A and Tan, C},
   Title = {Finite time blow up in the hyperbolic Boussinesq
             system},
   Journal = {Advances in Mathematics},
   Volume = {325},
   Pages = {34-55},
   Publisher = {Elsevier BV},
   Year = {2018},
   Month = {February},
   url = {http://dx.doi.org/10.1016/j.aim.2017.11.019},
   Abstract = {In recent work of Luo and Hou [10], a new scenario for
             finite time blow up in solutions of 3D Euler equation has
             been proposed. The scenario involves a ring of hyperbolic
             points of the flow located at the boundary of a cylinder. In
             this paper, we propose a two dimensional model that we call
             “hyperbolic Boussinesq system”. This model is designed
             to provide insight into the hyperbolic point blow up
             scenario. The model features an incompressible velocity
             vector field, a simplified Biot–Savart law, and a
             simplified term modeling buoyancy. We prove that finite time
             blow up happens for a natural class of initial
             data.},
   Doi = {10.1016/j.aim.2017.11.019},
   Key = {fds330278}
}

@article{fds340825,
   Author = {Kiselev, A and Tan, C},
   Title = {Global regularity for 1D eulerian dynamics with singular
             interaction forces},
   Journal = {SIAM Journal on Mathematical Analysis},
   Volume = {50},
   Number = {6},
   Pages = {6208-6229},
   Publisher = {Society for Industrial & Applied Mathematics
             (SIAM)},
   Year = {2018},
   Month = {January},
   url = {http://dx.doi.org/10.1137/17M1141515},
   Abstract = {The Euler-Poisson-alignment (EPA) system appears in
             mathematical biology and is used to model, in a hydrodynamic
             limit, a set of agents interacting through mutual
             attraction/repulsion as well as alignment forces. We
             consider one-dimensional EPA system with a class of singular
             alignment terms as well as natural attraction/repulsion
             terms. The singularity of the alignment kernel produces an
             interesting effect regularizing the solutions of the
             equation and leading to global regularity for wide range of
             initial data. This was recently observed in [Do et al.,
             Arch. Ration. Mech. Anal., 228(2018), pp. 1-37]. Our goal in
             this paper is to generalize the result and to incorporate
             the attractive/repulsive potential. We prove that global
             regularity persists for these more general
             models.},
   Doi = {10.1137/17M1141515},
   Key = {fds340825}
}

@article{fds330279,
   Author = {Choi, K and Hou, TY and Kiselev, A and Luo, G and Sverak, V and Yao,
             Y},
   Title = {On the Finite-Time Blowup of a One-Dimensional Model for the
             Three-Dimensional Axisymmetric Euler Equations},
   Journal = {Communications on Pure and Applied Mathematics},
   Volume = {70},
   Number = {11},
   Pages = {2218-2243},
   Publisher = {WILEY},
   Year = {2017},
   Month = {November},
   url = {http://dx.doi.org/10.1002/cpa.21697},
   Abstract = {In connection with the recent proposal for possible
             singularity formation at the boundary for solutions of
             three-dimensional axisymmetric incompressible Euler's
             equations (Luo and Hou, Proc. Natl. Acad. Sci. USA (2014)),
             we study models for the dynamics at the boundary and show
             that they exhibit a finite-time blowup from smooth data. ©
             2017 Wiley Periodicals, Inc.},
   Doi = {10.1002/cpa.21697},
   Key = {fds330279}
}

@article{fds330280,
   Author = {Kiselev, A and Yao, Y and Zlatoš, A},
   Title = {Local Regularity for the Modified SQG Patch
             Equation},
   Journal = {Communications on Pure and Applied Mathematics},
   Volume = {70},
   Number = {7},
   Pages = {1253-1315},
   Publisher = {WILEY},
   Year = {2017},
   Month = {July},
   url = {http://dx.doi.org/10.1002/cpa.21677},
   Abstract = {We study the patch dynamics on the whole plane and on the
             half-plane for a family of active scalars called modified
             surface quasi-geostrophic (SQG) equations. These involve a
             parameter α that appears in the power of the kernel in
             their Biot-Savart laws and describes the degree of
             regularity of the equation. The values α=0 and α=½
             correspond to the two-dimensional Euler and SQG equations,
             respectively. We establish here local-in-time regularity for
             these models, for all α ∊ (0,½) on the whole plane and
             for all small α > 0 on the half-plane. We use the latter
             result in [16], where we show existence of regular initial
             data on the half-plane that lead to a finite-time
             singularity.© 2016 Wiley Periodicals, Inc.},
   Doi = {10.1002/cpa.21677},
   Key = {fds330280}
}

@article{fds330282,
   Author = {Kiselev, A and Xu, X},
   Title = {Suppression of Chemotactic Explosion by Mixing},
   Journal = {Archive for Rational Mechanics and Analysis},
   Volume = {222},
   Number = {2},
   Pages = {1077-1112},
   Publisher = {Springer Nature},
   Year = {2016},
   Month = {November},
   url = {http://dx.doi.org/10.1007/s00205-016-1017-8},
   Abstract = {Chemotaxis plays a crucial role in a variety of processes in
             biology and ecology. In many instances, processes involving
             chemical attraction take place in fluids. One of the most
             studied PDE models of chemotaxis is given by the
             Keller–Segel equation, which describes a population
             density of bacteria or mold which is attracted chemically to
             substance they secrete. Solutions of the Keller–Segel
             equation can exhibit dramatic collapsing behavior, where
             density concentrates positive mass in a measure zero region.
             A natural question is whether the presence of fluid flow can
             affect singularity formation by mixing the bacteria thus
             making concentration harder to achieve. In this paper, we
             consider the parabolic-elliptic Keller–Segel equation in
             two and three dimensions with an additional advection term
             modeling ambient fluid flow. We prove that for any initial
             data, there exist incompressible fluid flows such that the
             solution to the equation stays globally regular. On the
             other hand, it is well known that when the fluid flow is
             absent, there exists initial data leading to finite time
             blow up. Thus the presence of fluid flow can prevent the
             singularity formation. We discuss two classes of flows that
             have the explosion arresting property. Both classes are
             known as very efficient mixers. The first class are the
             relaxation enhancing (RE) flows of (Ann Math:643–674,
             2008). These flows are stationary. The second class of flows
             are the Yao–Zlatos near-optimal mixing flows (Mixing and
             un-mixing by incompressible flows. arXiv:1407.4163, 2014),
             which are time dependent. The proof is based on the
             nonlinear version of the relaxation enhancement construction
             of (Ann Math:643–674, 2008), and on some variations of the
             global regularity estimate for the Keller–Segel
             model.},
   Doi = {10.1007/s00205-016-1017-8},
   Key = {fds330282}
}

@article{fds330283,
   Author = {Popov, IY and Kurasov, PA and Naboko, SN and Kiselev, AA and Ryzhkov,
             AE and Yafyasov, AM and Miroshnichenko, GP and Karpeshina, YE and Kruglov, VI and Pankratova, TF and Popov, AI},
   Title = {A distinguished mathematical physicist Boris S.
             Pavlov},
   Journal = {Nanosystems: Physics, Chemistry, Mathematics},
   Pages = {782-788},
   Publisher = {ITMO University},
   Year = {2016},
   Month = {October},
   url = {http://dx.doi.org/10.17586/2220-8054-2016-7-5-782-788},
   Doi = {10.17586/2220-8054-2016-7-5-782-788},
   Key = {fds330283}
}

@article{fds330281,
   Author = {Kiselev, A and Ryzhik, L and Yao, Y and Zlatoš, A},
   Title = {Finite time singularity for the modified SQG patch
             equation},
   Journal = {Annals of Mathematics},
   Volume = {184},
   Number = {3},
   Pages = {909-948},
   Publisher = {Annals of Mathematics, Princeton U},
   Year = {2016},
   Month = {January},
   url = {http://dx.doi.org/10.4007/annals.2016.184.3.7},
   Abstract = {It is well known that the incompressible Euler equations in
             two dimensions have globally regular solutions. The inviscid
             surface quasi-geostrophic (SQG) equation has a Biot-Savart
             law that is one derivative less regular than in the Euler
             case, and the question of global regularity for its
             solutions is still open. We study here the patch dynamics in
             the half-plane for a family of active scalars that
             interpolates between these two equations, via a parameter α
             ε [0, 1/2] appearing in the kernels of their Biot-Savart
             laws. The values α = 0 and α = 1/2 correspond to the 2D
             Euler and SQG cases, respectively. We prove global in time
             regularity for the 2D Euler patch model, even if the patches
             initially touch the boundary of the half-plane. On the other
             hand, for any suffciently small α > 0, we exhibit initial
             data that lead to a singularity in finite time. Thus, these
             results show a phase transition in the behavior of solutions
             to these equations and provide a rigorous foundation for
             classifying the 2D Euler equations as critical.},
   Doi = {10.4007/annals.2016.184.3.7},
   Key = {fds330281}
}

@article{fds330284,
   Author = {Kiselev, A and Zlatoš, A},
   Title = {Blow up for the 2D Euler equation on some bounded
             domains},
   Journal = {Journal of Differential Equations},
   Volume = {259},
   Number = {7},
   Pages = {3490-3494},
   Publisher = {Elsevier BV},
   Year = {2015},
   Month = {October},
   url = {http://dx.doi.org/10.1016/j.jde.2015.04.027},
   Abstract = {We find a smooth solution of the 2D Euler equation on a
             bounded domain which exists and is unique in a natural class
             locally in time, but blows up in finite time in the sense of
             its vorticity losing continuity. The domain's boundary is
             smooth except at two points, which are interior
             cusps.},
   Doi = {10.1016/j.jde.2015.04.027},
   Key = {fds330284}
}

@article{fds330285,
   Author = {Choi, K and Kiselev, A and Yao, Y},
   Title = {Finite Time Blow Up for a 1D Model of 2D Boussinesq
             System},
   Journal = {Communications in Mathematical Physics},
   Volume = {334},
   Number = {3},
   Pages = {1667-1679},
   Publisher = {Springer Nature},
   Year = {2015},
   Month = {March},
   url = {http://dx.doi.org/10.1007/s00220-014-2146-2},
   Abstract = {The 2D conservative Boussinesq system describes inviscid,
             incompressible, buoyant fluid flow in a gravity field. The
             possibility of finite time blow up for solutions of this
             system is a classical problem of mathematical hydrodynamics.
             We consider a 1D model of the 2D Boussinesq system motivated
             by a particular finite time blow up scenario. We prove that
             finite time blow up is possible for the solutions to the
             model system.},
   Doi = {10.1007/s00220-014-2146-2},
   Key = {fds330285}
}

@article{fds361422,
   Author = {Choi, K and Hou, TY and Kiselev, A and Luo, G and Sverak, V and Yao,
             Y},
   Title = {On the Finite-Time Blowup of a 1D Model for the 3D
             Axisymmetric Euler Equations},
   Year = {2014},
   Month = {July},
   Abstract = {In connection with the recent proposal for possible
             singularity formation at the boundary for solutions of 3d
             axi-symmetric incompressible Euler's equations (Luo and Hou,
             2013), we study models for the dynamics at the boundary and
             show that they exhibit a finite-time blow-up from smooth
             data.},
   Key = {fds361422}
}

@article{fds330286,
   Author = {Kiselev, A and Šverák, V},
   Title = {Small scale creation for solutions of the incompressible
             two-dimensional Euler equation},
   Journal = {Annals of Mathematics},
   Volume = {180},
   Number = {3},
   Pages = {1205-1220},
   Publisher = {Annals of Mathematics, Princeton U},
   Year = {2014},
   Month = {January},
   url = {http://dx.doi.org/10.4007/annals.2014.180.3.9},
   Abstract = {We construct an initial data for the two-dimensional Euler
             equation in a disk for which the gradient of vorticity
             exhibits double exponential growth in time for all times.
             This estimate is known to be sharp - the double exponential
             growth is the fastest possible growth rate. © 2014
             Department of Mathematics, Princeton University.},
   Doi = {10.4007/annals.2014.180.3.9},
   Key = {fds330286}
}

@article{fds330287,
   Author = {Iyer, G and Kiselev, A and Xu, X},
   Title = {Lower bounds on the mix norm of passive scalars advected by
             incompressible enstrophy-constrained flows},
   Journal = {Nonlinearity},
   Volume = {27},
   Number = {5},
   Pages = {973-985},
   Publisher = {IOP Publishing},
   Year = {2014},
   Month = {January},
   url = {http://dx.doi.org/10.1088/0951-7715/27/5/973},
   Abstract = {Consider a diffusion-free passive scalar θ being mixed by
             an incompressible flow u on the torus d. Our aim is to study
             how well this scalar can be mixed under an enstrophy
             constraint on the advecting velocity field. Our main result
             shows that the mix-norm (∥ θ (t)∥H-1) is bounded below
             by an exponential function of time. The exponential decay
             rate we obtain is not universal and depends on the size of
             the support of the initial data. We also perform numerical
             simulations and confirm that the numerically observed decay
             rate scales similarly to the rigorous lower bound, at least
             for a significant initial period of time. The main idea
             behind our proof is to use the recent work of Crippa and De
             Lellis (2008 J. Reine Angew. Math. 616 15-46) making
             progress towards the resolution of Bressan's rearrangement
             cost conjecture. © 2014 IOP Publishing Ltd & London
             Mathematical Society.},
   Doi = {10.1088/0951-7715/27/5/973},
   Key = {fds330287}
}

@article{fds330288,
   Author = {Dabkowski, M and Kiselev, A and Silvestre, L and Vicol,
             V},
   Title = {Global well-posedness of slightly supercritical active
             scalar equations},
   Journal = {Analysis and PDE},
   Volume = {7},
   Number = {1},
   Pages = {43-72},
   Publisher = {Mathematical Sciences Publishers},
   Year = {2014},
   Month = {January},
   url = {http://dx.doi.org/10.2140/apde.2014.7.43},
   Abstract = {The paper is devoted to the study of slightly supercritical
             active scalars with nonlocal diffusion. We prove global
             regularity for the surface quasigeostrophic (SQG) and
             Burgers equations, when the diffusion term is supercritical
             by a symbol with roughly logarithmic behavior at infinity.
             We show that the result is sharp for the Burgers equation.
             We also prove global regularity for a slightly supercritical
             two-dimensional Euler equation. Our main tool is a nonlocal
             maximum principle which controls a certain modulus of
             continuity of the solutions. ©2014 Mathematical Sciences
             Publishers.},
   Doi = {10.2140/apde.2014.7.43},
   Key = {fds330288}
}

@article{fds330289,
   Author = {Kiselev, A and Nazarov, F},
   Title = {A simple energy pump for the surface quasi-geostrophic
             equation},
   Journal = {Nonlinear Partial Differential Equations: The Abel Symposium
             2010},
   Pages = {175-179},
   Publisher = {Springer Berlin Heidelberg},
   Year = {2012},
   Month = {December},
   url = {http://dx.doi.org/10.1007/978-3-642-25361-4_9},
   Abstract = {We consider the question of growth of high order Sobolev
             norms of solutions of the conservative surface
             quasi-geostrophic equation. We show that if s > 0 is large
             then for every given A there exists initial data with a norm
             that is small in Hs such that the Hs norm of corresponding
             solution at some time exceeds A. The idea of the
             construction is quasilinear. We use a small perturbation of
             a stable shear flow. The shear flow can be shown to create
             small scales in the perturbation part of the flow. The
             control is lost once the nonlinear effects become too large.
             © Springer-Verlag Berlin Heidelberg 2012.},
   Doi = {10.1007/978-3-642-25361-4_9},
   Key = {fds330289}
}

@article{fds330290,
   Author = {Kiselev, A and Ryzhik, L},
   Title = {Biomixing by chemotaxis and efficiency of biological
             reactions: The critical reaction case},
   Journal = {Journal of Mathematical Physics},
   Volume = {53},
   Number = {11},
   Pages = {115609-115609},
   Publisher = {AIP Publishing},
   Year = {2012},
   Month = {November},
   url = {http://dx.doi.org/10.1063/1.4742858},
   Abstract = {Many phenomena in biology involve both reactions and
             chemotaxis. These processes can clearly influence each
             other, and chemotaxis can play an important role in
             sustaining and speeding up the reaction. In continuation of
             our work [A. Kiselev and L. Ryzhik, "Biomixing by chemotaxis
             and enhancement of biological reactions," Comm. Partial
             Differential Equations37, 298-318 (2012)]10.1080/03605302.2011.589879,
             we consider a model with a single density function involving
             diffusion, advection, chemotaxis, and absorbing reaction.
             The model is motivated, in particular, by the studies of
             coral broadcast spawning, where experimental observations of
             the efficiency of fertilization rates significantly exceed
             the data obtained from numerical models that do not take
             chemotaxis (attraction of sperm gametes by a chemical
             secreted by egg gametes) into account. We consider the case
             of the weakly coupled quadratic reaction term, which is the
             most natural from the biological point of view and was left
             open in Kiselev and Ryzhik ["Biomixing by chemotaxis and
             enhancement of biological reactions," Comm. Partial
             Differential Equations37, 298-318 (2012)]10.1080/03605302.2011.589879.
             The result is that similarly to Kiselev and Ryzhik
             ["Biomixing by chemotaxis and enhancement of biological
             reactions," Comm. Partial Differential Equations37, 298-318
             (2012)]10.1080/03605302.2011.589879, the chemotaxis plays a
             crucial role in ensuring efficiency of reaction. However,
             mathematically, the picture is quite different in the
             quadratic reaction case and is more subtle. The reaction is
             now complete even in the absence of chemotaxis, but the
             timescales are very different. Without chemotaxis, the
             reaction is very slow, especially for the weak reaction
             coupling. With chemotaxis, the timescale and efficiency of
             reaction are independent of the coupling parameter. © 2012
             American Institute of Physics.},
   Doi = {10.1063/1.4742858},
   Key = {fds330290}
}

@article{fds330291,
   Author = {Dabkowski, M and Kiselev, A and Vicol, V},
   Title = {Global well-posedness for a slightly supercritical surface
             quasi-geostrophic equation},
   Journal = {Nonlinearity},
   Volume = {25},
   Number = {5},
   Pages = {1525-1535},
   Publisher = {IOP Publishing},
   Year = {2012},
   Month = {May},
   url = {http://dx.doi.org/10.1088/0951-7715/25/5/1525},
   Abstract = {We use a non-local maximum principle to prove the global
             existence of smooth solutions for a slightly supercritical
             surface quasi-geostrophic equation. By this we mean that the
             velocity field u is obtained from the active scalar by a
             Fourier multiplier with symbol iζ ⊥|ζ| -1m(|ζ|), where
             m is a smooth increasing function that grows slower than log
             log|ζ| as |ζ| → ∞. © 2012 IOP Publishing Ltd & London
             Mathematical Society.},
   Doi = {10.1088/0951-7715/25/5/1525},
   Key = {fds330291}
}

@article{fds330292,
   Author = {Kiselev, A and Ryzhik, L},
   Title = {Biomixing by Chemotaxis and Enhancement of Biological
             Reactions},
   Journal = {Communications in Partial Differential Equations},
   Volume = {37},
   Number = {2},
   Pages = {298-318},
   Publisher = {Informa UK Limited},
   Year = {2012},
   Month = {February},
   url = {http://dx.doi.org/10.1080/03605302.2011.589879},
   Abstract = {Many phenomena in biology involve both reactions and
             chemotaxis. These processes can clearly influence each
             other, and chemotaxis can play an important role in
             sustaining and speeding up the reaction. However, to the
             best of our knowledge, the question of reaction enhancement
             by chemotaxis has not yet received extensive treatment
             either analytically or numerically. We consider a model with
             a single density function involving diffusion, advection,
             chemotaxis, and absorbing reaction. The model is motivated,
             in particular, by studies of coral broadcast spawning, where
             experimental observations of the efficiency of fertilization
             rates significantly exceed the data obtained from numerical
             models that do not take chemotaxis (attraction of sperm
             gametes by a chemical secreted by egg gametes) into account.
             We prove that in the framework of our model, chemotaxis
             plays a crucial role. There is a rigid limit to how much the
             fertilization efficiency can be enhanced if there is no
             chemotaxis but only advection and diffusion. On the other
             hand, when chemotaxis is present, the fertilization rate can
             be arbitrarily close to being complete provided that the
             chemotactic attraction is sufficiently strong. Moreover, an
             interesting feature of the estimates on fertilization rate
             and timescales in the chemotactic case is that they do not
             depend on the amplitude of the reaction term. © 2012
             Copyright Taylor and Francis Group, LLC.},
   Doi = {10.1080/03605302.2011.589879},
   Key = {fds330292}
}

@article{fds330293,
   Author = {Kiselev, A},
   Title = {Nonlocal maximum principles for active scalars},
   Journal = {Advances in Mathematics},
   Volume = {227},
   Number = {5},
   Pages = {1806-1826},
   Publisher = {Elsevier BV},
   Year = {2011},
   Month = {August},
   url = {http://dx.doi.org/10.1016/j.aim.2011.03.019},
   Abstract = {Active scalars appear in many problems of fluid dynamics.
             The most common examples of active scalar equations are 2D
             Euler, Burgers, and 2D surface quasi-geostrophic equations.
             Many questions about regularity and properties of solutions
             of these equations remain open. We develop the idea of
             nonlocal maximum principle introduced in Kiselev, Nazarov
             and Volberg (2007) [19], formulating a more general
             criterion and providing new applications. The most
             interesting application is finite time regularization of
             weak solutions in the supercritical regime. © 2011 Elsevier
             Inc.},
   Doi = {10.1016/j.aim.2011.03.019},
   Key = {fds330293}
}

@article{fds330294,
   Author = {Kiselev, A and Nazarov, F},
   Title = {Variation on a theme of caffarelli and vasseur},
   Journal = {Journal of Mathematical Sciences},
   Volume = {166},
   Number = {1},
   Pages = {31-39},
   Publisher = {Springer Nature},
   Year = {2010},
   Month = {March},
   url = {http://dx.doi.org/10.1007/s10958-010-9842-z},
   Abstract = {Recently, using DiGiorgi-type techniques, Caffarelli and
             Vasseur have shown that a certain class of weak solutions to
             the drift diffusion equation with initial data in L2 gain
             Ḧolder continuity, provided that the BMO norm of the drift
             velocity is bounded uniformly in time. We show a related
             result: a uniform bound on the BMO norm of a smooth velocity
             implies a uniform bound on the Cβ norm of the solution for
             some β > 0. We apply elementary tools involving the control
             of Ḧolder norms by using test functions. In particular,
             our approach offers a third proof of the global regularity
             for the critical surface quasigeostrophic (SQG) equation in
             addition to the two proofs obtained earlier. Bibliography: 6
             titles. © 2010 Springer Science+Business Media,
             Inc.},
   Doi = {10.1007/s10958-010-9842-z},
   Key = {fds330294}
}

@article{fds330295,
   Author = {Kiselev, A and Nazarov, F},
   Title = {Global regularity for the critical dispersive dissipative
             surface quasi-geostrophic equation},
   Journal = {Nonlinearity},
   Volume = {23},
   Number = {3},
   Pages = {549-554},
   Publisher = {IOP Publishing},
   Year = {2010},
   Month = {February},
   url = {http://dx.doi.org/10.1088/0951-7715/23/3/006},
   Abstract = {We consider the surface quasi-geostrophic equation with
             dispersive forcing and critical dissipation. We prove the
             global existence of smooth solutions given sufficiently
             smooth initial data. This is done using a maximum principle
             for the solutions involving conservation of a certain family
             of moduli of continuity. © 2010 IOP Publishing Ltd and
             London Mathematical Society.},
   Doi = {10.1088/0951-7715/23/3/006},
   Key = {fds330295}
}

@article{fds330296,
   Author = {Berestycki, H and Kiselev, A and Novikov, A and Ryzhik,
             L},
   Title = {The explosion problem in a flow},
   Journal = {Journal d'Analyse Mathematique},
   Volume = {110},
   Number = {1},
   Pages = {31-65},
   Publisher = {Springer Nature},
   Year = {2010},
   Month = {January},
   url = {http://dx.doi.org/10.1007/s11854-010-0002-7},
   Abstract = {We consider the explosion problem in an incompressible flow
             introduced in [5]. We use a novel Lp - L∞ estimate for
             elliptic advection-diffusion problems to show that the
             explosion threshold obeys a positive lower bound which is
             uniform in the advecting flow. We also identify the flows
             for which the explosion threshold tends to infinity as their
             amplitude grows and obtain an effective description of the
             explosion threshold in the strong flow asymptotics in
             two-dimensional cellular flows. © 2010 Hebrew University
             Magnes Press.},
   Doi = {10.1007/s11854-010-0002-7},
   Key = {fds330296}
}

@article{fds330297,
   Author = {Kiselev, A},
   Title = {Regularity and blow up for active scalars},
   Journal = {Mathematical Modelling of Natural Phenomena},
   Volume = {5},
   Number = {4},
   Pages = {225-255},
   Publisher = {E D P SCIENCES},
   Year = {2010},
   Month = {January},
   url = {http://dx.doi.org/10.1051/mmnp/20105410},
   Abstract = {We review some recent results for a class of fluid mechanics
             equations called active scalars, with fractional
             dissipation. Our main examples are the surface
             quasi-geostrophic equation, the Burgers equation, and the
             Cordoba-Cordoba-Fontelos model. We discuss nonlocal maximum
             principle methods which allow to prove existence of global
             regular solutions for the critical dissipation. We also
             recall what is known about the possibility of finite time
             blow up in the supercritical regime. © EDP Sciences,
             2010.},
   Doi = {10.1051/mmnp/20105410},
   Key = {fds330297}
}

@article{fds330298,
   Author = {Kim, A and Kiselev, A},
   Title = {Absolutely continuous spectrum of discrete Schrödinger
             operators with slowly oscillating potentials},
   Journal = {Mathematische Nachrichten},
   Volume = {282},
   Number = {4},
   Pages = {552-568},
   Publisher = {WILEY},
   Year = {2009},
   Month = {April},
   url = {http://dx.doi.org/10.1002/mana.200810754},
   Abstract = {We show that when a potential bn of a discrete Schrödinger
             operator, defined on l2(Z{double-struck}+), slowly
             oscillates satisfying the conditions bn ∈ l∞ and ∂bn =
             bn+1 - bn ∈ lp, p < 2, then all solutions of the equation
             Ju = Eu are bounded near infinity at almost every E ∈ [-2
             + lim supn→∞ bn, 2 + lim supn→∞ bn] ∩ [-2 + lim
             infn→∞bn, 2 + lim infn→∞bn]. We derive an asymptotic
             formula for generalized eigenfunctions in this case. As a
             corollary, the absolutely continuous spectrum of the
             corresponding Jacobi operator is essentially supported on
             the same interval of E. © 2009 WILEY-VCH Verlag GmbH & Co.
             KGaA, Weinheim.},
   Doi = {10.1002/mana.200810754},
   Key = {fds330298}
}

@article{fds331091,
   Author = {Kiselev, A},
   Title = {Some recent results on the critical surface
             quasi-geostrophic equation: A review},
   Journal = {HYPERBOLIC PROBLEMS: THEORY, NUMERICS AND APPLICATIONS, PART
             1},
   Volume = {67},
   Pages = {105-122},
   Publisher = {AMER MATHEMATICAL SOC},
   Editor = {Tadmor, E and Liu, J and Tzavaras, A},
   Year = {2009},
   Month = {January},
   ISBN = {978-0-8218-4729-9},
   Key = {fds331091}
}

@article{fds331092,
   Author = {Kiselev, A},
   Title = {Diffusion and Mixing in Fluid Flow: A Review},
   Pages = {357-369},
   Publisher = {Springer Netherlands},
   Year = {2009},
   ISBN = {9789048128099},
   url = {http://dx.doi.org/10.1007/978-90-481-2810-5_24},
   Doi = {10.1007/978-90-481-2810-5_24},
   Key = {fds331092}
}

@article{fds330300,
   Author = {Kiselev, A and Shterenberg, R and Zlatoš, A},
   Title = {Relaxation enhancement by time-periodic flows},
   Journal = {Indiana University Mathematics Journal},
   Volume = {57},
   Number = {5},
   Pages = {2137-2152},
   Publisher = {Indiana University Mathematics Journal},
   Year = {2008},
   Month = {December},
   url = {http://dx.doi.org/10.1512/iumj.2008.57.3349},
   Abstract = {We study enhancement of diffusive mixing by fast
             incompressible time-periodic flows. The class of
             relaxation-enhancing flows that are especially efficient in
             speeding up mixing has been introduced in [2]. The
             relaxation-enhancing property of a flow has been shown to be
             intimately related to the properties of the dynamical system
             it generates. In particular, time-independent flows u such
             that the operator u · ▽ has sufficiently smooth
             eigenfunctions are not relaxation-enhancing. Here we extend
             results of [2] to time-periodic flows u(x, t) and, in
             particular, show that there exist flows such that for each
             fixed time the flow is Hamiltonian, but the resulting
             time-dependent flow is relaxation-enhancing. Thus we confirm
             the physical intuition that time dependence of a flow may
             aid mixing. We also provide an extension of our results to
             the case of a nonlinear diffusion model. The proofs are
             based on a general criterion for the decay of a semigroup
             generated by an operator of the form Γ + iAL(t) with a
             negative unbounded self-adjoint operator Γ, a time-periodic
             self-adjoint operator-valued function L(t), and a parameter
             A ≫ 1.},
   Doi = {10.1512/iumj.2008.57.3349},
   Key = {fds330300}
}

@article{fds330299,
   Author = {Kiselev, A and Nazarov, F and Shterenberg, R},
   Title = {Blow up and regularity for fractal burgers
             equation},
   Journal = {Dynamics of Partial Differential Equations},
   Volume = {5},
   Number = {3},
   Pages = {211-240},
   Publisher = {International Press of Boston},
   Year = {2008},
   Month = {January},
   url = {http://dx.doi.org/10.4310/DPDE.2008.v5.n3.a2},
   Abstract = {The paper is a comprehensive study of the existence,
             uniqueness, blow up and regularity properties of solutions
             of the Burgers equation with fractional dissipation. We
             prove existence of the finite time blow up for the power of
             Laplacian α < 1/2, and global existence as well as
             analyticity of solution for α ≥ 1/2. We also prove the
             existence of solutions with very rough initial data uo ∈
             Lp, 1 < p < ∞. Many of the results can be extended to a
             more general class of equations, including the surface
             quasi-geostrophic equation. ©2008 International
             Press.},
   Doi = {10.4310/DPDE.2008.v5.n3.a2},
   Key = {fds330299}
}

@article{fds331093,
   Author = {Constantin, P and Kiselev, A and Ryzhik, L and Zlatoš,
             A},
   Title = {Diusion and mixing in fluid flow},
   Journal = {Annals of Mathematics},
   Volume = {168},
   Number = {2},
   Pages = {643-674},
   Publisher = {Annals of Mathematics, Princeton U},
   Year = {2008},
   Month = {January},
   url = {http://dx.doi.org/10.4007/annals.2008.168.643},
   Abstract = {We study enhancement of diffusive mixing on a compact
             Riemannian manifold by a fast incompressible flow. Our main
             result is a sharp description of the class of flows that
             make the deviation of the solution from its average
             arbitrarily small in an arbitrarily short time, provided
             that the flow amplitude is large enough. The necessary and
             suffcient condition on such flows is expressed naturally in
             terms of the spectral properties of the dynamical system
             associated with the flow. In particular, we find that weakly
             mixing flows always enhance dissipation in this sense. The
             proofs are based on a general criterion for the decay of the
             semigroup generated by an operator of the form Γ + iAL with
             a negative unbounded self-adjoint operator Γ, a
             self-adjoint operator L, and parameter A » 1. In
             particular, they employ the RAGE theorem describing
             evolution of a quantum state belonging to the continuous
             spectral subspace of the hamiltonian (related to a classical
             theorem of Wiener on Fourier transforms of measures).
             Applications to quenching in reaction-diffusion equations
             are also considered.},
   Doi = {10.4007/annals.2008.168.643},
   Key = {fds331093}
}

@article{fds330301,
   Author = {Kiselev, A and Nazarov, F and Volberg, A},
   Title = {Global well-posedness for the critical 2D dissipative
             quasi-geostrophic equation},
   Journal = {Inventiones Mathematicae},
   Volume = {167},
   Number = {3},
   Pages = {445-453},
   Publisher = {Springer Nature},
   Year = {2007},
   Month = {March},
   url = {http://dx.doi.org/10.1007/s00222-006-0020-3},
   Abstract = {We give an elementary proof of the global well-posedness for
             the critical 2D dissipative quasi-geostrophic equation. The
             argument is based on a non-local maximum principle involving
             appropriate moduli of continuity. © 2006
             Springer-Verlag.},
   Doi = {10.1007/s00222-006-0020-3},
   Key = {fds330301}
}

@article{fds331946,
   Author = {Denisov, SA and Kiselev, A},
   Title = {Spectral properties of schrodinger operators with decaying
             potentials},
   Journal = {SPECTRAL THEORY AND MATHEMATICAL PHYSICS: A FESTSCHRIFT IN
             HONOR OF BARRY SIMON'S 60TH BIRTHDAY},
   Volume = {76},
   Pages = {565-589},
   Publisher = {AMER MATHEMATICAL SOC},
   Editor = {Gesztesy, F and Deift, P and Galvez, C and Perry, P and Schlag,
             W},
   Year = {2007},
   Month = {January},
   Key = {fds331946}
}

@article{fds330302,
   Author = {Kiselev, A and Zlatoš, A},
   Title = {Quenching of combustion by shear flows},
   Journal = {Duke Mathematical Journal},
   Volume = {132},
   Number = {1},
   Pages = {49-72},
   Publisher = {Duke University Press},
   Year = {2006},
   Month = {March},
   url = {http://dx.doi.org/10.1215/S0012-7094-06-13212-X},
   Abstract = {We consider a model describing premixed combustion in the
             presence of fluid flow: a reaction-diffusion equation with
             passive advection and ignition-type nonlinearity. What kinds
             of velocity profiles are capable of quenching (suppressing)
             any given flame, provided the velocity's amplitude is
             adequately large? Even for shear flows, the solution turns
             out to be surprisingly subtle. In this article we provide a
             sharp characterization of quenching for shear flows; the
             flow can quench any initial data if and only if the velocity
             profile does not have an interval larger than a certain
             critical size where it is identically constant. The
             efficiency of quenching depends strongly on the geometry and
             scaling of the flow. We discuss the cases of slowly and
             quickly varying flows, proving rigorously scaling laws that
             have been observed earlier in numerical experiments. The
             results require new estimates on the behavior of the
             solutions to the advection-enhanced diffusion equation (also
             known as passive scalar in physical literature), a classical
             model describing a wealth of phenomena in nature. The
             technique involves probabilistic and partial-differential-equation
             (PDE) estimates, in particular, applications of Malliavin
             calculus and the central limit theorem for
             martingales.},
   Doi = {10.1215/S0012-7094-06-13212-X},
   Key = {fds330302}
}

@article{fds330303,
   Author = {Fannjiang, A and Kiselev, A and Ryzhik, L},
   Title = {Quenching of reaction by cellular flows},
   Journal = {Geometric and Functional Analysis},
   Volume = {16},
   Number = {1},
   Pages = {40-69},
   Publisher = {Springer Nature},
   Year = {2006},
   Month = {February},
   url = {http://dx.doi.org/10.1007/s00039-006-0554-y},
   Abstract = {We consider a reaction-diffusion equation in a cellular
             flow. We prove that in the strong flow regime there are two
             possible scenarios for the initial data that is compactly
             supported and the size of the support is large enough. If
             the flow cells are large compared to the reaction length
             scale, propagating fronts will always form. For small cell
             size, any finitely supported initial data will be quenched
             by a sufficiently strong flow. We estimate that the flow
             amplitude required to quench the initial data of support L 0
             is A > CL 04 ln(L 0). The essence of the problem is the
             question about the decay of the L ∞-norm of a solution to
             the advection-diffusion equation, and the relation between
             this rate of decay and the properties of the Hamiltonian
             system generated by the two-dimensional incompressible fluid
             flow. © Birkhäuser Verlag.},
   Doi = {10.1007/s00039-006-0554-y},
   Key = {fds330303}
}

@article{fds330304,
   Author = {Andrzejewski, D and Butzlaff, E and Kiselev, A and Markely,
             LRA},
   Title = {Enhancement of combustion by drift in a coupled
             reaction-diffusion model},
   Journal = {Communications in Mathematical Sciences},
   Volume = {4},
   Number = {1},
   Pages = {213-225},
   Publisher = {International Press of Boston},
   Year = {2006},
   url = {http://dx.doi.org/10.4310/cms.2006.v4.n1.a8},
   Doi = {10.4310/cms.2006.v4.n1.a8},
   Key = {fds330304}
}

@article{fds330305,
   Author = {Berestycki, H and Hamel, F and Kiselev, A and Ryzhik,
             L},
   Title = {Quenching and propagation in KPP reaction-diffusion
             equations with a heat loss},
   Journal = {Archive for Rational Mechanics and Analysis},
   Volume = {178},
   Number = {1},
   Pages = {57-80},
   Publisher = {Springer Nature},
   Year = {2005},
   Month = {October},
   url = {http://dx.doi.org/10.1007/s00205-005-0367-4},
   Abstract = {We consider a reaction-diffusion system of KPP type in a
             shear flow and with a non-zero heat-loss parameter. We
             establish criteria for the flame blow-off and propagation,
             and identify the propagation speed in terms of the
             exponential decay of the initial data. We prove the
             existence of travelling fronts for all speeds c>max(0,c*) in
             the case Le=1, where c* ∈ ℝ. This seems to be one of the
             first non-perturbative results on the existence of fronts
             for the thermo-diffusive system in higher dimensions. ©
             Springer-Verlag (2005).},
   Doi = {10.1007/s00205-005-0367-4},
   Key = {fds330305}
}

@article{fds330306,
   Author = {Kiselev, A and Zlatoš, A},
   Title = {On discrete models of the Euler equation},
   Journal = {International Mathematics Research Notices},
   Number = {38},
   Pages = {2315-2339},
   Year = {2005},
   Month = {August},
   url = {http://dx.doi.org/10.1155/imrn.2005.2315},
   Doi = {10.1155/imrn.2005.2315},
   Key = {fds330306}
}

@article{fds330307,
   Author = {Kiselev, A},
   Title = {Imbedded singular continuous spectrum for Schrödinger
             operators},
   Journal = {Journal of the American Mathematical Society},
   Volume = {18},
   Number = {3},
   Pages = {571-603},
   Year = {2005},
   Month = {July},
   url = {http://dx.doi.org/10.1090/S0894-0347-05-00489-3},
   Doi = {10.1090/S0894-0347-05-00489-3},
   Key = {fds330307}
}

@article{fds330308,
   Author = {Germinet, F and Kiselev, A and Tcheremchantsev,
             S},
   Title = {Transfer matrices and transport for Schrödinger
             operators},
   Journal = {Annales de l’institut Fourier},
   Volume = {54},
   Number = {3},
   Pages = {787-830},
   Publisher = {Cellule MathDoc/CEDRAM},
   Year = {2004},
   url = {http://dx.doi.org/10.5802/aif.2034},
   Doi = {10.5802/aif.2034},
   Key = {fds330308}
}

@article{fds330309,
   Author = {Constantin, P and Kiselev, A and Ryzhik, L},
   Title = {Fronts in Reactive Convection: Bounds, Stability, and
             Instability},
   Journal = {Communications on Pure and Applied Mathematics},
   Volume = {56},
   Number = {12},
   Pages = {1781-1803},
   Publisher = {WILEY},
   Year = {2003},
   Month = {December},
   url = {http://dx.doi.org/10.1002/cpa.10110},
   Abstract = {This paper examines a simplified active combustion model in
             which the reaction influences the flow. We consider front
             propagation in a reactive Boussinesq system in an infinite
             vertical strip. Nonlinear stability of planar fronts is
             established for narrow domains when the Rayleigh number is
             not too large. Planar fronts are shown to be linearly
             unstable with respect to long-wavelength perturbations if
             the Rayleigh number is sufficiently large. We also prove
             uniform bounds on the bulk burning rate and the Nusselt
             number in the KPP reaction case. © 2003 Wiley Periodicals,
             Inc.},
   Doi = {10.1002/cpa.10110},
   Key = {fds330309}
}

@article{fds330310,
   Author = {Vladimirova, N and Constantin, P and Kiselev, A and Ruchayskiy, O and Ryzhik, L},
   Title = {Flame enhancement and quenching in fluid
             flows},
   Journal = {Combustion Theory and Modelling},
   Volume = {7},
   Number = {3},
   Pages = {487-508},
   Publisher = {Informa UK Limited},
   Year = {2003},
   Month = {September},
   url = {http://dx.doi.org/10.1088/1364-7830/7/3/303},
   Abstract = {We perform direct numerical simulations of an advected
             scalar field which diffuses and reacts according to a
             nonlinear reaction law. The objective is to study how the
             bulk burning rate of the reaction is affected by an imposed
             flow. In particular, we are interested in comparing the
             numerical results with recently predicted analytical upper
             and lower bounds. We focus on the reaction enhancement and
             quenching phenomena for two classes of imposed model flows
             with different geometries: periodic shear flow and cellular
             flow. We are primarily interested in the fast advection
             regime. We find that the bulk burning rate v in a shear flow
             satisfies v ∼ aU + b where U is the typical flow velocity
             and a is a constant depending on the relationship between
             the oscillation length scale of the flow and laminar front
             thickness. For cellular flow, we obtain v ∼ U1/4. We also
             study the flame extinction (quenching) for an ignition-type
             reaction law and compactly supported initial data for the
             scalar field. We find that in a shear flow the flame of size
             W can be typically quenched by a flow with amplitude U ∼
             αW. The constant α depends on the geometry of the flow and
             tends to infinity if the flow profile has a plateau larger
             than a critical size. In a cellular flow, we find that the
             advection strength required for quenching is U ∼ W4 if the
             cell size is smaller than a critical value.},
   Doi = {10.1088/1364-7830/7/3/303},
   Key = {fds330310}
}

@article{fds330312,
   Author = {Kiselev, A and Last, Y and Simon, B},
   Title = {Stability of singular spectral types under decaying
             pertubations},
   Journal = {Journal of Functional Analysis},
   Volume = {198},
   Number = {1},
   Pages = {1-27},
   Publisher = {Elsevier BV},
   Year = {2003},
   Month = {February},
   url = {http://dx.doi.org/10.1016/S0022-1236(02)00053-8},
   Abstract = {We look at invariance of a.e. boundary condition spectral
             behavior under perturbations, W , of half-line, continuum or
             discrete Schrödinger operators. We extend the results of
             del Rio, Simon, Stolz from compactly supported W's to
             suitable short-range W. We also discuss invariance of the
             local Hausdroff dimension of spectral measures under such
             pertubations. © 2002 Elsevier Science (USA). All rights
             reserved.},
   Doi = {10.1016/S0022-1236(02)00053-8},
   Key = {fds330312}
}

@article{fds330311,
   Author = {Christ, M and Kiselev, A},
   Title = {Absolutely continuous spectrum of Stark operators},
   Journal = {Arkiv for Matematik},
   Volume = {41},
   Number = {1},
   Pages = {1-33},
   Publisher = {International Press of Boston},
   Year = {2003},
   Month = {January},
   url = {http://dx.doi.org/10.1007/BF02384565},
   Abstract = {We prove several new results on the absolutely continuous
             spectra of perturbed one-dimensional Stark operators. First,
             we find new classes of perturbations, characterized mainly
             by smoothness conditions, which preserve purely absolutely
             continuous spectrum. Then we establish stability of the
             absolutely continuous spectrum in more general situations,
             where imbedded singular spectrum may occur. We present two
             kinds of optimal conditions for the stability of absolutely
             continuous spectrum: decay and smoothness. In the decay
             direction, we show that a sufficient (in the power scale)
             condition is |q(x)| ≤ C(1 + |x|)-1/4-ε; in the smoothness
             direction, a sufficient condition in Holder classes is q ∈
             C1/2+ε(R). On the other hand, we show that there exist
             potentials which both satisfy |q(x)| ≤ C(1 + |x|)-1/4 and
             belong to C1/2(R) for which the spectrum becomes purely
             singular on the whole real axis, so that the above results
             are optimal within the scales considered.},
   Doi = {10.1007/BF02384565},
   Key = {fds330311}
}

@article{fds330313,
   Author = {Killip, R and Kiselev, A and Last, Y},
   Title = {Dynamical upper bounds on wavepacket spreading},
   Journal = {American Journal of Mathematics},
   Volume = {125},
   Number = {5},
   Pages = {1165-1198},
   Publisher = {Johns Hopkins University Press},
   Year = {2003},
   Month = {January},
   url = {http://dx.doi.org/10.1353/ajm.2003.0031},
   Abstract = {We derive a general upper bound on the spreading rate of
             wavepackets in the framework of Sohrödinger time evolution.
             Our result consists of showing that a portion of the
             wavepacket cannot escape outside a ball whose size grows
             dynamically in time, where the rate of this growth is
             determined by properties of the spectral measure and by
             spatial properties of solutions of an associated
             time-independent Schrödinger equation. We also derive a new
             lower bound on the spreading rate, which is strongly
             connected with our upper bound. We apply these new bounds to
             the Fibonacci Hamiltonian - the most studied one-dimensional
             model of quasicrystals. As a result, we obtain for this
             model upper and lower dynamical bounds establishing
             wavepacket spreading rates which are intermediate between
             ballistic transport and localization. The bounds have the
             same qualitative behavior in the limit of large
             coupling.},
   Doi = {10.1353/ajm.2003.0031},
   Key = {fds330313}
}

@article{fds330315,
   Author = {Gesztesy, F and Kiselev, A and Makarov, KA},
   Title = {Uniqueness results for matrix-valued Schrödinger, Jacobi,
             and Dirac-type operators},
   Journal = {Mathematische Nachrichten},
   Volume = {239-240},
   Number = {1},
   Pages = {103-145},
   Publisher = {WILEY},
   Year = {2002},
   Month = {August},
   url = {http://dx.doi.org/10.1002/1522-2616(200206)239:1<103::AID-MANA103>3.0.CO;2-F},
   Abstract = {Let g(z,x) denote the diagonal Green's matrix of a
             self-adjoint m × m matrix-valued Schrödinger operator H =
             -d2/dx2Im + Q in L2(ℝ)m, m ∈ ℕ. One of the principal
             results proven in this paper states that for a fixed x0 ∈
             ℝ and z ∈ ℂ+, g(z,x0) and g′(z,x0) uniquely
             determine the matrix-valued m × m potential Q(x) for a.e. x
             ∈ ℝ. We also prove the following local version of this
             result. Let gj(z,x), j = 1, 2 be the diagonal Green's
             matrices of the self-adjoint Schrödinger operators Hj =
             -d2/dx2Im + Qj in L2(ℝ)m. Suppose that for fixed a > 0 and
             x0 ∈ ℝ, ∥g1(z,x0) - g2(z,x0)∥ℂm×m +
             ∥g′1(z,x0) - g′2(z,x0)∥ℂm×m = |z|→∞
             O(e-2Im(z1/2)a) for z inside a cone along the imaginary axis
             with vertex zero and opening angle less than π/2, excluding
             the real axis. Then Q1(x) = Q2(x) for a.e. x ∈ [x0 - a,x0
             + a]. Analogous results are proved for matrix-valued Jacobi
             and Dirac-type operators.},
   Doi = {10.1002/1522-2616(200206)239:1<103::AID-MANA103>3.0.CO;2-F},
   Key = {fds330315}
}

@article{fds330314,
   Author = {Christ, M and Kiselev, A},
   Title = {Scattering and wave operators for one-dimensional
             Schrödinger operators with slowly decaying nonsmooth
             potentials},
   Journal = {Geometric and Functional Analysis},
   Volume = {12},
   Number = {6},
   Pages = {1174-1234},
   Publisher = {Springer Nature},
   Year = {2002},
   Month = {January},
   url = {http://dx.doi.org/10.1007/s00039-002-1174-9},
   Abstract = {We prove existence of modified wave operators for
             one-dimensional Schrödinger equations with potential in
             LP(ℝ). p < 2. If in addition the potential is
             conditionally integrable, then the usual Möller wave
             operators exist. We also prove asymptotic completeness of
             these wave operators for some classes of random potentials,
             and for almost every boundary condition for any given
             potential.},
   Doi = {10.1007/s00039-002-1174-9},
   Key = {fds330314}
}

@article{fds330316,
   Author = {Constantin, P and Kiselev, A and Ryzhik, L},
   Title = {Quenching of flames by fluid advection},
   Journal = {Communications on Pure and Applied Mathematics},
   Volume = {54},
   Number = {11},
   Pages = {1320-1342},
   Publisher = {WILEY},
   Year = {2001},
   Month = {November},
   url = {http://dx.doi.org/10.1002/cpa.3000},
   Abstract = {We consider a simple scalar reaction-advection-diffusion
             equation with ignition-type nonlinearity and discuss the
             following question: What kinds of velocity profiles are
             capable of quenching any given flame, provided the
             velocity's amplitude is adequately large? Even for shear
             flows, the answer turns out to be surprisingly subtle. If
             the velocity profile changes in space so that it is nowhere
             identically constant (or if it is identically constant only
             in a region of small measure), then the flow can quench any
             initial data. But if the velocity profile is identically
             constant in a sizable region, then the ensuing flow is
             incapable of quenching large enough flames, no matter how
             much larger the amplitude of this velocity is. The constancy
             region must be wider across than a couple of laminar
             propagating front widths. The proof uses a linear PDE
             associated to the nonlinear problem, and quenching follows
             when the PDE is hypoelliptic. The techniques used allow the
             derivation of new, nearly optimal bounds on the speed of
             traveling-wave solutions. © 2001 John Wiley & Sons,
             Inc.},
   Doi = {10.1002/cpa.3000},
   Key = {fds330316}
}

@article{fds330317,
   Author = {Kiselev, A and Ryzhik, L},
   Title = {An upper bound for the bulk burning rate for
             systems},
   Journal = {Nonlinearity},
   Volume = {14},
   Number = {5},
   Pages = {1297-1310},
   Publisher = {IOP Publishing},
   Year = {2001},
   Month = {September},
   url = {http://dx.doi.org/10.1088/0951-7715/14/5/319},
   Abstract = {We consider a system of reaction-diffusion equations with
             passive advection term and Lewis number Le not equal to one.
             Such systems are used to describe chemical reactions in a
             flow in a situation where temperature and material
             diffusivities are not equal. It is expected that the fluid
             advection will distort the reaction front, increasing the
             area of reaction and thus speeding up the reaction process.
             While a variety of estimates on the influence of the flow on
             reaction are available for a single reaction-diffusion
             equation (corresponding to the case of Lewis number equal to
             one), the case of the system is largely open. We prove a
             general upper bound on the reaction rate in such systems in
             terms of the reaction rate for a single reaction-diffusion
             equation, showing that the long-time average of reaction
             rate with Le ≠ 1 does not exceed the Le = 1 case. Thus the
             upper estimates derived for Le = 1 apply to the systems.
             Both front-like and compact initial data (hot blob) are
             considered.},
   Doi = {10.1088/0951-7715/14/5/319},
   Key = {fds330317}
}

@article{fds330320,
   Author = {Christ, M and Kiselev, A},
   Title = {WKB asymptotic behavior of almost all generalized
             eigenfunctions for one-dimensional Schrödinger operators
             with slowly decaying potentials},
   Journal = {Journal of Functional Analysis},
   Volume = {179},
   Number = {2},
   Pages = {426-447},
   Publisher = {Elsevier BV},
   Year = {2001},
   Month = {February},
   url = {http://dx.doi.org/10.1006/jfan.2000.3688},
   Abstract = {We prove the WKB asymptotic behavior of solutions of the
             differential equation -d2u/dx2+V(x)u=Eu for a.e. E>A where
             V=V1+V2, V1∈Lp(R), and V2 is bounded from above with
             A=limsupx→∞V(x), while V′2(x)∈Lp(R), 1≤p<2. These
             results imply that Schrödinger operators with such
             potentials have absolutely continuous spectrum on (A, ∞).
             We also establish WKB asymptotic behavior of solutions for
             some energy-dependent potentials. © 2001 Academic
             Press.},
   Doi = {10.1006/jfan.2000.3688},
   Key = {fds330320}
}

@article{fds330321,
   Author = {Christ, M and Kiselev, A},
   Title = {Maximal functions associated to filtrations},
   Journal = {Journal of Functional Analysis},
   Volume = {179},
   Number = {2},
   Pages = {409-425},
   Publisher = {Elsevier BV},
   Year = {2001},
   Month = {February},
   url = {http://dx.doi.org/10.1006/jfan.2000.3687},
   Abstract = {Let T be a bounded linear, or sublinear, operator from Lp(Y)
             to Lq(X). A maximal operator T*f(x)=supjT(f·χYj)(x) is
             associated to any sequence of subsets Yj of Y. Under the
             hypotheses that q>p and the sets Yj are nested, we prove
             that T* is also bounded. Classical theorems of Menshov and
             Zygmund are obtained as corollaries. Multilinear
             generalizations of this theorem are also established. These
             results are motivated by applications to the spectral
             analysis of Schrödinger operators. © 2001 Academic
             Press.},
   Doi = {10.1006/jfan.2000.3687},
   Key = {fds330321}
}

@article{fds330318,
   Author = {Kiselev, A and Ryzhik, L},
   Title = {Enhancement of the traveling front speeds in
             reaction-diffusion equations with advection},
   Journal = {Annales de l'Institut Henri Poincare (C) Analyse Non
             Lineaire},
   Volume = {18},
   Number = {3},
   Pages = {309-358},
   Publisher = {Elsevier BV},
   Year = {2001},
   Month = {January},
   url = {http://dx.doi.org/10.1016/S0294-1449(01)00068-3},
   Abstract = {We establish rigorous lower bounds on the speed of traveling
             fronts and on the bulk burning rate in reaction-diffusion
             equation with passive advection. The non-linearity is
             assumed to be of either KPP or ignition type. We consider
             two main classes of flows. Percolating flows, which are
             characterized by the presence of long tubes of streamlines
             mixing hot and cold material, lead to strong speed-up of
             burning which is linear in the amplitude of the flow, U. On
             the other hand the cellular flows, which have closed
             streamlines, are shown to produce weaker increase in
             reaction. For such flows we get a lower bound which grows as
             U1/5 for a large amplitude of the flow. © 2001 Éditions
             scientifiques et médicales Elsevier SAS.},
   Doi = {10.1016/S0294-1449(01)00068-3},
   Key = {fds330318}
}

@article{fds330319,
   Author = {Christ, M and Kiselev, A},
   Title = {WKB and spectral analysis of one-dimensional Schrödinger
             operators with slowly varying potentials},
   Journal = {Communications in Mathematical Physics},
   Volume = {218},
   Number = {2},
   Pages = {245-262},
   Publisher = {Springer Nature},
   Year = {2001},
   Month = {January},
   url = {http://dx.doi.org/10.1007/PL00005556},
   Abstract = {Consider a Schrödinger operator on L2 of the line, or of a
             half line with appropriate boundary conditions. If the
             potential tends to zero and is a finite sum of terms, each
             of which has a derivative of some order in L1 + Lp for some
             exponent p < 2, then an essential support of the the
             absolutely continuous spectrum equals ℝ+. Almost every
             generalized eigenfunction is bounded, and satisfies certain
             WKB-type asymptotics at infinity. If moreover these
             derivatives belong to Lp with respect to a weight |x|γ with
             γ > 0, then the Hausdorff dimension of the singular
             component of the spectral measure is strictly less than
             one.},
   Doi = {10.1007/PL00005556},
   Key = {fds330319}
}

@article{fds330322,
   Author = {Kiselev, A},
   Title = {Absolutely continuous spectrum of perturbed stark
             operators},
   Journal = {Transactions of the American Mathematical
             Society},
   Volume = {352},
   Number = {1},
   Pages = {243-256},
   Year = {2000},
   Month = {January},
   url = {http://dx.doi.org/10.1090/s0002-9947-99-02450-2},
   Abstract = {We prove new results on the stability of the absolutely
             continuous spectrum for perturbed Stark operators with
             decaying or satisfying certain smoothness assumption
             perturbation. We show that the absolutely continuous
             spectrum of the Stark operator is stable if the perturbing
             potential decays at the rate (1 + x)-1/3-ε or if it is
             continuously differentiate with derivative from the Holder
             space Ca(R), with any α > 0. © 1999 American Mathematical
             Society.},
   Doi = {10.1090/s0002-9947-99-02450-2},
   Key = {fds330322}
}

@article{fds330323,
   Author = {Constantin, P and Kiselev, A and Oberman, A and Ryzhik,
             L},
   Title = {Bulk burning rate in passive-reactive diffusion},
   Journal = {Archive for Rational Mechanics and Analysis},
   Volume = {154},
   Number = {1},
   Pages = {53-91},
   Publisher = {Springer Nature},
   Year = {2000},
   Month = {January},
   url = {http://dx.doi.org/10.1007/s002050000090},
   Abstract = {We consider a passive scalar that is advected by a
             prescribed mean zero divergence-free velocity field,
             diffuses, and reacts according to a KPP-type nonlinear
             reaction. We introduce a quantity, the bulk burning rate,
             that makes both mathematical and physical sense in general
             situations and extends the often ill-defined notion of front
             speed. We establish rigorous lower bounds for the bulk
             burning rate that are linear in the amplitude of the
             advecting velocity for a large class of flows. These
             "percolating" flows are characterized by the presence of
             tubes of streamlines connecting distant regions of burned
             and unburned material and generalize shear flows. The bound
             contains geometric information on the velocity streamlines
             and degenerates when these oscillate on scales that are
             finer than the width of the laminar burning region. We give
             also examples of very different kind of flows, cellular
             flows with closed streamlines, and rigorously prove that
             these can produce only sub-linear enhancement of the bulk
             burning rate.},
   Doi = {10.1007/s002050000090},
   Key = {fds330323}
}

@article{fds330324,
   Author = {Kiselev, A and Last, Y},
   Title = {Solutions, spectrum, and dynamics for schrödinger operators
             on infinite domains},
   Journal = {Duke Mathematical Journal},
   Volume = {102},
   Number = {1},
   Pages = {125-150},
   Publisher = {Duke University Press},
   Year = {2000},
   Month = {January},
   url = {http://dx.doi.org/10.1215/S0012-7094-00-10215-3},
   Doi = {10.1215/S0012-7094-00-10215-3},
   Key = {fds330324}
}

@article{fds330326,
   Author = {Kiselev, A and Remling, C and Simon, B},
   Title = {Effective perturbation methods for one-dimensional
             Schrödinger operators},
   Journal = {Journal of Differential Equations},
   Volume = {151},
   Number = {2},
   Pages = {290-312},
   Publisher = {Elsevier BV},
   Year = {1999},
   Month = {January},
   url = {http://dx.doi.org/10.1006/jdeq.1998.3514},
   Doi = {10.1006/jdeq.1998.3514},
   Key = {fds330326}
}

@article{fds330325,
   Author = {Kiselev, A},
   Title = {An interpolation theorem related to the A.E. convergence of
             integral operators},
   Journal = {Proceedings of the American Mathematical
             Society},
   Volume = {127},
   Number = {6},
   Pages = {1781-1785},
   Year = {1999},
   Month = {January},
   url = {http://dx.doi.org/10.1090/s0002-9939-99-04681-x},
   Abstract = {We show that for integral operators of general form the norm
             bounds in Lorentz spaces imply certain norm bounds for the
             maximal function. As a consequence, the a.e. convergence for
             the integral operators on Lorentz spaces follows from the
             appropriate norm estimates. ©1999 American Mathematical
             Society.},
   Doi = {10.1090/s0002-9939-99-04681-x},
   Key = {fds330325}
}

@article{fds330327,
   Author = {Christ, M and Kiselev, A},
   Title = {Absolutely continuous spectrum for one-dimensional
             Schrödinger operators with slowly decaying potentials: Some
             optimal results},
   Journal = {Journal of the American Mathematical Society},
   Volume = {11},
   Number = {4},
   Pages = {771-797},
   Year = {1998},
   Month = {January},
   url = {http://dx.doi.org/10.1090/s0894-0347-98-00276-8},
   Doi = {10.1090/s0894-0347-98-00276-8},
   Key = {fds330327}
}

@article{fds330328,
   Author = {Kiselev, A},
   Title = {Stability of the absolutely continuous spectrum of the
             Schrödinger equation under slowly decaying perturbations
             and A.E. convergence of integral operators},
   Journal = {Duke Mathematical Journal},
   Volume = {94},
   Number = {3},
   Pages = {619-646},
   Publisher = {Duke University Press},
   Year = {1998},
   Month = {January},
   url = {http://dx.doi.org/10.1215/S0012-7094-98-09425-X},
   Doi = {10.1215/S0012-7094-98-09425-X},
   Key = {fds330328}
}

@article{fds330329,
   Author = {Kiselev, A and Last, Y and Simon, B},
   Title = {Modified prüfer and EFGP transforms and the spectral
             analysis of one dimensional schrödinger
             operators},
   Journal = {Communications in Mathematical Physics},
   Volume = {194},
   Number = {1},
   Pages = {1-45},
   Publisher = {Springer Nature},
   Year = {1998},
   Month = {January},
   url = {http://dx.doi.org/10.1007/s002200050346},
   Doi = {10.1007/s002200050346},
   Key = {fds330329}
}

@article{fds330330,
   Author = {Kiselev, A},
   Title = {Some examples in one-dimensional "geometric" scattering on
             manifolds},
   Journal = {Journal of Mathematical Analysis and Applications},
   Volume = {212},
   Number = {1},
   Pages = {263-280},
   Publisher = {Elsevier BV},
   Year = {1997},
   Month = {August},
   url = {http://dx.doi.org/10.1006/jmaa.1997.5497},
   Abstract = {We consider "geometric" scattering for a Laplace-Beltrami
             operator on a compact Riemannian manifold inserted between
             "wires," that is, two half-lines. We discuss applicability
             and correctness of this model. With an example, we show that
             such a scattering problem may exhibit unusual properties:
             the transition coefficient has a sequence of sharp peaks
             which become more and more distant at high energy and
             otherwise turns to zero. © 1997 Academic
             Press.},
   Doi = {10.1006/jmaa.1997.5497},
   Key = {fds330330}
}

@article{fds330331,
   Author = {Christ, M and Kiselev, A and Remling, C},
   Title = {The absolutely continuous spectrum of one-dimensional
             Schrödinger operators with decaying potentials},
   Journal = {Mathematical Research Letters},
   Volume = {4},
   Number = {5},
   Pages = {719-723},
   Publisher = {International Press of Boston},
   Year = {1997},
   Month = {January},
   url = {http://dx.doi.org/10.4310/MRL.1997.v4.n5.a9},
   Doi = {10.4310/MRL.1997.v4.n5.a9},
   Key = {fds330331}
}

@article{fds330332,
   Author = {Kiselev, A},
   Title = {Absolutely continuous spectrum of one-dimensional
             Schrödinger operators and Jacobi matrices with slowly
             decreasing potentials},
   Journal = {Communications in Mathematical Physics},
   Volume = {179},
   Number = {2},
   Pages = {377-399},
   Publisher = {Springer Nature},
   Year = {1996},
   Month = {January},
   url = {http://dx.doi.org/10.1007/bf02102594},
   Abstract = {We prove that for any one-dimensional Schrödinger operator
             with potential V(x) satisfying decay condition |V(x)| ≦
             Cx-3/4-ε, the absolutely continuous spectrum fills the
             whole positive semi-axis. The description of the set in ℝ+
             on which the singular part of the spectral measure might be
             supported is also given. Analogous results hold for Jacobi
             matrices.},
   Doi = {10.1007/bf02102594},
   Key = {fds330332}
}

@article{fds330333,
   Author = {Kiselev, AA and Popov, IY},
   Title = {Indefinite metric and scattering by a domain with a small
             hole},
   Journal = {Mathematical Notes},
   Volume = {58},
   Number = {6},
   Pages = {1276-1285},
   Publisher = {Springer Nature},
   Year = {1995},
   Month = {January},
   url = {http://dx.doi.org/10.1007/BF02304886},
   Abstract = {For the problem of plane waves scattered by a domain with a
             small hole, we suggest a model based on the theory of
             self-adjoint extensions of symmetric operators in a space
             with indefinite metric. For two-dimensional problems of
             scattering on a line with a hole and on a semi-ellipse
             connected by a hole with a half-plane, we justify the choice
             of extension that guarantees the coincidence of the model
             solution with the solution of the “actual” problem in
             the far zone with a high degree of accuracy. © 1996, Plenum
             Publishing Corporation. All rights reserved.},
   Doi = {10.1007/BF02304886},
   Key = {fds330333}
}

@article{fds330334,
   Author = {Kiselev, A and Simon, B},
   Title = {Rank one perturbations with infinitesimal
             coupling},
   Journal = {Journal of Functional Analysis},
   Volume = {130},
   Number = {2},
   Pages = {345-356},
   Publisher = {Elsevier BV},
   Year = {1995},
   Month = {January},
   url = {http://dx.doi.org/10.1006/jfan.1995.1074},
   Abstract = {We consider a positive self-adjoint operator A and formal
             rank one perturbations B = A + α(φ, ·)φ, where φ ∈
             H-2(A) but φ ∉ H-1 (A), with Hs(A) the usual scale of
             spaces. We show that B can be defined for such φ and what
             are essentially negative infinitesimal values of α. In a
             sense we will make precise, every rank one perturbation is
             one of three forms: (i) φ ∈ H-1(A), α ∈ R; (ii) φ ∈
             H-1, α = ∞; or (iii) the new type we consider here. ©
             1995 Academic Press Limited.},
   Doi = {10.1006/jfan.1995.1074},
   Key = {fds330334}
}

@article{fds357912,
   Author = {Kiselev, AA and Pavlov, BS},
   Title = {Eigenfrequencies and eigenfunctions of the Laplacian for
             Neumann boundary conditions in a system of two coupled
             cavities},
   Journal = {Theoretical and Mathematical Physics},
   Volume = {100},
   Number = {3},
   Pages = {1065-1074},
   Year = {1994},
   Month = {September},
   url = {http://dx.doi.org/10.1007/BF01018571},
   Abstract = {A model Laplacian with Neumann boundary conditions (Neumann
             problem) in a system of two cavities joined by a thin
             channel is investigated. An expression is obtained for the
             resolvent and also the first terms in the asymptotic
             expansions of the eigenvalues and eigenfunctions with
             respect to the small coupling parameter. © 1995 Plenum
             Publishing Corporation.},
   Doi = {10.1007/BF01018571},
   Key = {fds357912}
}

@article{fds357913,
   Author = {Kiselev, AA and Pavlov, BS},
   Title = {Essential spectrum of the Laplacian for the Neumann problem
             in a model region of complicated structure},
   Journal = {Theoretical and Mathematical Physics},
   Volume = {99},
   Number = {1},
   Pages = {383-395},
   Year = {1994},
   Month = {April},
   url = {http://dx.doi.org/10.1007/BF01018792},
   Abstract = {A class of regions in which the Laplacian for the Neumann
             problem has an essential spectrum is considered. The
             connection between the geometrical characteristics of the
             region and spectral properties of the Laplacian for the
             Neumann problem is studied in specific examples. © 1994
             Plenum Publishing Corporation.},
   Doi = {10.1007/BF01018792},
   Key = {fds357913}
}

 

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