Results 41 to 50 of about 129,718 (286)

Palatini Formalism of 5-Dimensional Kaluza-Klein Theory

, 2005
The Einstein field equations can be derived in $n$ dimensions ($n>2$) by the variations of the Palatini action. The Killing reduction of 5-dimensional Palatini action is studied on the assumption that pentads and Lorentz connections are preserved by the ...
de Vega H. J., JIANBING SHAO, Krauss L., Kremer G. N., Liang C., MUXIN HAN, Polchinski J., Romano D., Vollick D. N., Yang X., YONGGE MA, YOU DING   +11 more
core   +1 more source

Characterizing Affine Vector Fields on Pseudo-Riemannian Manifolds

Axioms
We study the characteristics of affine vector fields on pseudo-Riemannian manifolds and provide tensorial formulas that characterize these vector fields.
Norah Alshehri, Mohammed Guediri
doaj   +1 more source

A Geometric characterization of Finsler manifolds of constant curvature K=1

International Journal of Mathematics and Mathematical Sciences, 2000
We prove that a Finsler manifold 𝔽m is of constant curvature K=1 if and only if the unit horizontal Liouville vector field is a Killing vector field on the indicatrix bundle IM of 𝔽m.
A. Bejancu, H. R. Farran
doaj   +1 more source

Connecting and Closed Geodesics of a Kropina Metric

Advanced Nonlinear Studies, 2021
We prove some results about existence of connecting and closed geodesics in a manifold endowed with a Kropina metric. These have applications to both null geodesics of spacetimes endowed with a null Killing vector field and Zermelo’s navigation problem ...
Caponio Erasmo, Giannoni Fabio, Masiello Antonio, Suhr Stefan   +3 more
doaj   +1 more source

Charged particle in higher dimensional weakly charged rotating black hole spacetime

, 2010
We study charged particle motion in weakly charged higher dimensional black holes. To describe the electromagnetic field we use a test field approximation and use the higher dimensional Kerr-NUT-(A)dS metric as a background geometry. It is shown that for
Frolov, Valeri P., Krtous, Pavel
core   +1 more source

A Twisting Electrovac Solution of Type II with the Cosmological Constant [PDF]

, 2000
An exact solution of the current-free Einstein-Maxwell equations with the cosmological constant is presented. It is of Petrov type II, and its double principal null vector is geodesic, shear-free, expanding, and twisting.
D. Kramer, J. K. Kowalczyński, J. Leroy, K. Bajer   +3 more
core   +2 more sources

Peroxidasin enables melanoma immune escape by inhibiting natural killer cell cytotoxicity

Molecular Oncology, EarlyView.
Peroxidasin (PXDN) is secreted by melanoma cells and binds the NK cell receptor NKG2D, thereby suppressing NK cell activation and cytotoxicity. PXDN depletion restores NKG2D signaling and enables effective NK cell–mediated melanoma killing. These findings identify PXDN as a previously unrecognized immune evasion factor and a potential target to improve
Hsu‐Min Sung, David Bickel, Lena C. M. Krause, Daria Ezeriņa, Christian Ickes, Julian Wojtachnia, Christine S. Gibhardt, Magdalena Shumanska, Khadija Wahni, Andrea Paluschkiwitz, Julia Malo Pueyo, Ekaterina Baranova, Wim Vranken, Hedwig Stanisz, Ioana Stejerean‐Todoran, Michael P. Schön, Joris Messens, Ivan Bogeski   +17 more
wiley   +1 more source

On Finsler spacetimes with a timelike Killing vector field

, 2018
We study Finsler spacetimes and Killing vector fields taking care of the fact that the generalized metric tensor associated to the Lorentz-Finsler function $L$ is in general well defined only on a subset of the slit tangent bundle.
Caponio, Erasmo, Stancarone, Giuseppe
core   +1 more source

Conformal Killing Vector Fields of Riemannian Manifolds

Dhaka University Journal of Science, 2022
The main aim of this article to study about vector fields of manifold and how these vector fields will be Killing and Conformal Killing vector fields. Conformal transformation of Weyl rescaling which is conformally related to metrices from g to g, Levi-Civita connection Δ , Lie derivative, torsion with tensor concept of manifold N in a multi-linear map
Md Shapan Miah, Khondokar M Ahmed
openaire   +1 more source

Drug‐Free Thrombolysis Mediated by Physically Activated Micro/Nanoparticles

Advanced Functional Materials, EarlyView.
Overview of particle‐mediated thrombolytic effects (thermal, mechanical, and chemical) and their activating physical stimuli (light, ultrasound, and magnetic field) in drug‐free thrombolysis. ABSTRACT Thrombus‐associated disorders rank among the world's leading causes of death, with ischemic heart disease and stroke as the main contributors.
Pierre Sarfati, Yoann Lalatonne, Cédric Chauvierre   +2 more
wiley   +1 more source