Results 41 to 50 of about 14,465,781 (332)
Twisted Alexander Polynomials and Symplectic Structures [PDF]
American Journal of Mathematics, 2008 Let N be a closed, oriented 3-manifold. A folklore conjecture states that S 1 × N admits a symplectic structure only if N admits a fibration over the circle. The purpose of this paper is to provide evidence to this conjecture studying suitable twisted Alexander polynomials of N , and showing that their behavior is the same as of those of fibered 3 ...
Friedl, Stefan, Vidussi, Stefano
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Twist and lock: nutshell structures for high strength and energy absorption
Royal Society Open Science, 2021 Nutshells achieve remarkable properties by optimizing structure and chemistry at different hierarchical levels. Probing nutshells from the cellular down to the nano- and molecular level by microchemical and nanomechanical imaging techniques reveals ...
Nannan Xiao +7 more
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Theoretical and Applied Mechanics Letters, 2018 : Twist structures have diverse applications, ranging from dragline, electrical cable, and intelligent structure. Among these applications, tension deformation can't be avoided during the fabrication and working processes, which often leads to the twist ...
Hexin Cui +3 more
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Filopodia rotate and coil by actively generating twist in their actin shaft
Nature Communications, 2022 The authors show how tubular surface structures in all cell types, have the ability to twist and perform rotary sweeping motion to explore the extracellular environment. This has implications for migration, sensing and cell communication.
Natascha Leijnse +11 more
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Moiré effects in graphene-hBN heterostructures
Physical Review Research, 2020 Encapsulating graphene in hexagonal boron nitride (hBN) has several advantages: The highest mobilities reported to date are achieved in this way, and precise nanostructuring of graphene becomes feasible through the protective hBN layers.
Yongping Du +3 more
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Twisted Jacobi manifolds, twisted Dirac–Jacobi structures and quasi-Jacobi bialgebroids [PDF]
Journal of Physics A: Mathematical and General, 2006 We study twisted Jacobi manifolds, a concept that we had introduced in a previous Note. Twisted Jacobi manifolds can be characterized using twisted Dirac-Jacobi, which are sub-bundles of Courant-Jacobi algebroids. We show that each twisted Jacobi manifold has an associated Lie algebroid with a 1-cocycle.
Costa, J. M. Nunes da, Petalidou, F.
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B-Meson Distribution Amplitudes of Geometric Twist vs. Dynamical Twist
, 2005 Two- and three-particle distribution amplitudes of heavy pseudoscalar mesons of well-defined geometric twist are introduced. They are obtained from appropriately parametrized vacuum-to-meson matrix elements by applying those twist projectors which ...
A. G. Grozin +6 more
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Parity-time symmetry meets photonics: A new twist in non-Hermitian optics [PDF]
, 2017 In the past decade, the concept of parity-time symmetry, originally introduced in non-Hermitian extensions of quantum mechanical theories, has come into thinking of photonics, providing a fertile ground for studying, observing, and utilizing some of the ...
S. Longhi
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Minimal Surfaces, Screw Dislocations and Twist Grain Boundaries
, 1999 Large twist-angle grain boundaries in layered structures are often described by Scherk's first surface whereas small twist-angle grain boundaries are usually described in terms of an array of screw dislocations.
A. R. Day +12 more
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Twisted waveguide accelerating structure [PDF]
AIP Conference Proceedings, 2001 Regular straight hollow waveguides have phase velocities of propagating electromagnetic waves greater than the free-space speed of light. However, it has been found that, if the waveguide is twisted, the phase velocities of the waveguide modes become slower.
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