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13 papers found.
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Surface counterterms and regularized holographic complexity

The holographic complexity is UV divergent. As a finite complexity, we propose a “regularized complexity” by employing a similar method to the holographic renor-malization. We add codimension-two boundary counterterms which do not contain any boundary stress tensor information. It means that we subtract only non-dynamic back-ground and all the dynamic information of holographic ...

Diffusion and butterfly velocity at finite density

We study diffusion and butterfly velocity (v B ) in two holographic models, linear axion and axion-dilaton model, with a momentum relaxation parameter (β) at finite density or chemical potential (μ). Axion-dilaton model is particularly interesting since it shows linear-T -resistivity, which may have something to do with the universal bound of diffusion. At finite density, there are ...

Homes’ law in holographic superconductor with Q-lattices

Homes’ law, ρ s = Cσ DC T c , is an empirical law satisfied by various superconductors with a material independent universal constant C, where ρ s is the superfluid density at zero temperature, T c is the critical temperature, and σ DC is the electric DC conductivity in the normal state close to T c . We study Homes’ law in holographic superconductor with Q-lattices and find that ...

Ward identity and Homes’ law in a holographic superconductor with momentum relaxation

We study three properties of a holographic superconductor related to conductivities, where momentum relaxation plays an important role. First, we find that there are constraints between electric, thermoelectric and thermal conductivities. The constraints are analytically derived by the Ward identities regarding diffeomorphism from field theory perspective. We confirm them by ...

A simple holographic superconductor with momentum relaxation

We study a holographic superconductor model with momentum relaxation due to massless scalar fields linear to spatial coordinates(ψ I = βδ Ii x i ), where β is the strength of momentum relaxation. In addition to the original superconductor induced by the chemical potential(μ) at β = 0, there exists a new type of superconductor induced by β even at μ = 0. It may imply a new ‘pairing’ ...

Thermoelectric conductivities at finite magnetic field and the Nernst effect

We study the thermoelectric conductivities of a strongly correlated system in the presence of a magnetic field by the gauge/gravity duality. We consider a class of Einstein-Maxwell-Dilaton theories with axion fields imposing momentum relaxation. General analytic formulas for the direct current (DC) conductivities and the Nernst signal are derived in terms of the black hole horizon ...

Coherent/incoherent metal transition in a holographic model

We study AC electric (σ), thermoelectric (α), and thermal \( \left(\overline{\kappa}\right) \) conductivities in a holographic model, which is based on 3+1 dimensional Einstein-Maxwell-scalar action. There is momentum relaxation due to massless scalar fields linear to spatial coordinate. The model has three field theory parameters: temperature (T), chemical potential (μ), and ...

DP2: Distributed 3D image segmentation using micro-labor workforce

Summary: This application note describes a new scalable semi-automatic approach, the Dual Point Decision Process, for segmentation of 3D structures contained in 3D microscopy. The segmentation problem is distributed to many individual workers such that each receives only simple questions regarding whether two points in an image are placed on the same object. A large pool of ...

Coenzyme Q10 ameliorates oxidative stress and prevents mitochondrial alteration in ischemic retinal injury

protein expression in ischemic retina. In addition, the CoQ10 significantly blocked activation of astroglial and Dongwook Lee and Keun-Young Kim have contributed equally to this work. - Elevated

The open string membrane paradigm with external electromagnetic fields

We study the effective geometry felt by the fluctuations of open strings living on the worldvolume of probe D-branes in the presence of background electromagnetic fields. This is captured by an effective action consisting of a Maxwell term and a topological term, with the role of the metric played by the open string metric. Studying generalized Eddington-Finkelstein coordinates for ...

Non-equilibrium physics at a holographic chiral phase transition

The D3/D7 system holographically describes an \( \mathcal{N} = 2 \) gauge theory which spontaneously breaks a chiral symmetry by the formation of a quark condensate in the presence of a magnetic field. At finite temperature it displays a first order phase transition. We study out of equilibrium dynamics associated with this transition by placing probe D7 branes in a geometry ...

Potential Energy Landscape and Robustness of a Gene Regulatory Network: Toggle Switch

Finding a multidimensional potential landscape is the key for addressing important global issues, such as the robustness of cellular networks. We have uncovered the underlying potential energy landscape of a simple gene regulatory network: a toggle switch. This was realized by explicitly constructing the steady state probability of the gene switch in the protein concentration space ...

Brimonidine Blocks Glutamate Excitotoxicity-Induced Oxidative Stress and Preserves Mitochondrial Transcription Factor A in Ischemic Retinal Injury

Glutamate excitotoxicity-induced oxidative stress have been linked to mitochondrial dysfunction in retinal ischemia and optic neuropathies including glaucoma. Brimonindine (BMD), an alpha 2-adrenergic receptor agonist, contributes to the neuroprotection of retinal ganglion cells (RGCs) against glutamate excitotoxicity or oxidative stress. However, the molecular mechanisms of ...