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Erratum To: Functional And Evolutionary Analyses Of The Mir156 And Mir529 Families In Land Plants.
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Inside an asymptotically flat hairy black hole
We study the interior of a recently constructed family of asymptotically
flat, charged black holes that develop (charged) scalar hair as one increases
their charge at fixed mass. Inside the horizon, these black holes resemble the
interior of a holographic superconductor. There are analogs of the Josephson
oscillations of the scalar field, and the final Kasner singularity depends very
sensitively on the black hole parameters near the onset of the instability. In
an Appendix, we give a general argument that Cauchy horizons cannot exist in a
large class of stationary black holes with scalar hair
Emergent Gauge Fields in Holographic Superconductors
Holographic superconductors have been studied so far in the absence of
dynamical electromagnetic fields, namely in the limit in which they coincide
with holographic superfluids. It is possible, however, to introduce dynamical
gauge fields if a Neumann-type boundary condition is imposed on the
AdS-boundary. In 3+1 dimensions, the dual theory is a 2+1 dimensional CFT whose
spectrum contains a massless gauge field, signaling the emergence of a gauge
symmetry. We study the impact of a dynamical gauge field in vortex
configurations where it is known to significantly affect the energetics and
phase transitions. We calculate the critical magnetic fields H_c1 and H_c2,
obtaining that holographic superconductors are of Type II (H_c1 < H_c2). We
extend the study to 4+1 dimensions where the gauge field does not appear as an
emergent phenomena, but can be introduced, by a proper renormalization, as an
external dynamical field. We also compare our predictions with those arising
from a Ginzburg-Landau theory and identify the generic properties of Abrikosov
vortices in holographic models.Comment: 19 pages, 14 figures, few comments added, version published in JHE
The phases of deuterium at extreme densities
We consider deuterium compressed to higher than atomic, but lower than
nuclear densities. At such densities deuterium is a superconducting quantum
liquid. Generically, two superconducting phases compete, a "ferromagnetic" and
a "nematic" one. We provide a power counting argument suggesting that the
dominant interactions in the deuteron liquid are perturbative (but screened)
Coulomb interactions. At very high densities the ground state is determined by
very small nuclear interaction effects that probably favor the ferromagnetic
phase. At lower densities the symmetry of the theory is effectively enhanced to
SU(3), and the quantum liquid enters a novel phase, neither ferromagnetic nor
nematic. Our results can serve as a starting point for investigations of the
phase dynamics of deuteron liquids, as well as exploration of the stability and
dynamics of the rich variety of topological objects that may occur in phases of
the deuteron quantum liquid, which range from Alice strings to spin skyrmions
to Z_2 vortices.Comment: 9 pages, 6 figures; v2: fixed typo
Magnetic Response in the Holographic Insulator/Superconductor Transition
We study the magnetic response of holographic superconductors exhibiting an
insulating "normal" phase. These materials can be realized as a CFT
compactified on a circle, which is dual to the AdS Soliton geometry. We study
the response under i) magnetic fields and ii) a Wilson line on the circle.
Magnetic fields lead to formation of vortices and allows one to infer that the
superconductor is of type II. The response to a Wilson line is in the form of
Aharonov-Bohm-like effects. These are suppressed in the holographic
conductor/superconductor transition but, instead, they are unsuppressed for the
insulator case. Holography, thus, predicts that generically insulators display
stronger Aharonov-Bohm effects than conductors. In the fluid-mechanical limit
the AdS Soliton is interpreted as a supersolid. Our results imply that
supersolids display unsuppressed Aharonov-Bohm (or "Sagnac") effects - stronger
than in superfluids.Comment: 31 pages, 24 figures; discussion on vortex lattice, few comments and
references added; article published in JHE
State-space Manifold and Rotating Black Holes
We study a class of fluctuating higher dimensional black hole configurations
obtained in string theory/ -theory compactifications. We explore the
intrinsic Riemannian geometric nature of Gaussian fluctuations arising from the
Hessian of the coarse graining entropy, defined over an ensemble of brane
microstates. It has been shown that the state-space geometry spanned by the set
of invariant parameters is non-degenerate, regular and has a negative scalar
curvature for the rotating Myers-Perry black holes, Kaluza-Klein black holes,
supersymmetric black holes, - configurations and the
associated BMPV black holes. Interestingly, these solutions demonstrate that
the principal components of the state-space metric tensor admit a positive
definite form, while the off diagonal components do not. Furthermore, the ratio
of diagonal components weakens relatively faster than the off diagonal
components, and thus they swiftly come into an equilibrium statistical
configuration. Novel aspects of the scaling property suggest that the
brane-brane statistical pair correlation functions divulge an asymmetric
nature, in comparison with the others. This approach indicates that all above
configurations are effectively attractive and stable, on an arbitrary
hyper-surface of the state-space manifolds. It is nevertheless noticed that
there exists an intriguing relationship between non-ideal inter-brane
statistical interactions and phase transitions. The ramifications thus
described are consistent with the existing picture of the microscopic CFTs. We
conclude with an extended discussion of the implications of this work for the
physics of black holes in string theory.Comment: 44 pages, Keywords: Rotating Black Holes; State-space Geometry;
Statistical Configurations, String Theory, M-Theory. PACS numbers: 04.70.-s
Physics of black holes; 04.70.Bw Classical black holes; 04.70.Dy Quantum
aspects of black holes, evaporation, thermodynamics; 04.50.Gh
Higher-dimensional black holes, black strings, and related objects. Edited
the bibliograph
An assessment of the integration between corporate social responsibility practices and management systems in Brazil aiming at sustainability in enterprises
The concept of corporate social responsibility (CSR) is associated with the idea that every organization should integrate environmental, economic and social issues as part of their organizational philosophy. In companies with a higher degree of development in terms of CSR, sustainable practices are integrated into management systems. When focusing on Latin America, this integration may be at its first steps, but there is a vacuum in the literature in this field. Based on this reality, this paper aims to evaluate the integration between CSR practices and management systems in companies in Brazil based on experts’ perceptions. Employing a conceptual model covering how stakeholder demands are incorporated in organizational practices using a continuous improvement approach, we performed a survey with experts in the area. Results revealed opportunities for improvements in all CSR practices evaluated, most of which were considered by the experts to have been implemented only superficially. In a comparative analysis, two practices stood out in relation to the others: reporting of CSR results to stakeholders and evaluation of the performance of CSR activities using pre-established indicators. Practices associated with planning of CSR activities are the most superficially implemented, adversely affecting CSR performance. The authors believe that the findings of this study could be useful for business managers and academics as guidance towards improved CSR efforts
First discovery of Holocene cryptotephra in Amazonia
The use of volcanic ash layers for dating and correlation (tephrochronology) is widely applied in the study of past environmental changes. We describe the first cryptotephra (non-visible volcanic ash horizon) to be identified in the Amazon basin, which is tentatively attributed to a source in the Ecuadorian Eastern Cordillera (0–1°S, 78-79°W), some 500-600 km away from our field site in the Peruvian Amazon. Our discovery 1) indicates that the Amazon basin has been subject to volcanic ash fallout during the recent past; 2) highlights the opportunities for using cryptotephras to date palaeoenvironmental records in the Amazon basin and 3) indicates that cryptotephra layers are preserved in a dynamic Amazonian peatland, suggesting that similar layers are likely to be present in other peat sequences that are important for palaeoenvironmental reconstruction. The discovery of cryptotephra in an Amazonian peatland provides a baseline for further investigation of Amazonian tephrochronology and the potential impacts of volcanism on vegetation
Objetos virtuais de aprendizagem: contribuições para o processo de aprendizagem em saúde e enfermagem
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