166 research outputs found
Searching for the dual of the Maxwell-Chern-Simons model minimally coupled to dynamical U(1) charged matter
The possibility of dual equivalence between the self-dual and the
Maxwell-Chern-Simons (MCS) models when the latter is coupled to dynamical, U(1)
fermionic charged matter is examined. The proper coupling in the self-dual
model is then disclosed using the iterative gauge embedding approach. We found
that the self-dual potential needs to couple directly to the Chern-Kernel of
the source in order to establish this equivalence besides the need for a
self-interaction term to render the matter sector unchanged.Comment: 4 pages, RevTeX, new references, accepted for publication on Phys.
Lett.
Radiative processes as a condensation phenomenon and the physical meaning of deformed canonical structures
Working with well known models in we discuss the physics behind the
deformation of the canonical structure of these theories. A new deformation is
constructed linking the massless scalar field theory with the self-dual theory.
This is the exact dual of the known deformation connecting the Maxwell theory
with the Maxwell-Chern-Simons theory. Duality is used to establish a web of
relations between the mentioned theories and a physical picture of the
deformation procedure is suggested.Comment: revtex4 file, 16 page
Instanton Cosmology and Domain Walls from M-theory and String Theory
The recent proposal by Hawking and Turok for obtaining an open inflationary
universe from singular instantons makes use of low-energy effective Lagrangians
describing gravity coupled to scalars and non-propagating antisymmetric
tensors. In this paper we derive some exact results for Lagrangians of this
type, obtained from spherical compactifications of M-theory and string theory.
In the case of the S^7 compactification of M-theory, we give a detailed
discussion of the cosmological solutions. We also show that the
lower-dimensional Lagrangians admit domain-wall solutions, which preserve one
half of the supersymmetry, and which approach AdS spacetimes near their
horizons.Comment: 51 pages, Latex (3 times). Discussion and references adde
Supergravity Solutions for BI Dyons
We construct partially localized supergravity counterpart solutions to the
1/2 supersymmetric non-threshold and the 1/4 supersymmetric threshold bound
state BI dyons in the D3-brane Dirac-Born-Infeld theory. Such supergravity
solutions have all the parameters of the BI dyons. By applying the IIA/IIB
T-duality transformations to these supergravity solutions, we obtain the
supergravity counterpart solutions to 1/2 and 1/4 supersymmetric BIons carrying
electric and magnetic charges of the worldvolume U(1) gauge field in the
Dirac-Born-Infeld theory in other dimensions.Comment: 17 pages, REVTeX, revised version to appear in Phys. Rev.
The Public Repository of Xenografts enables discovery and randomized phase II-like trials in mice
More than 90% of drugs with preclinical activity fail in human trials, largely due to insufficient efficacy. We hypothesized that adequately powered trials of patient-derived xenografts (PDX) in mice could efficiently define therapeutic activity across heterogeneous tumors. To address this hypothesis, we established a large, publicly available repository of well-characterized leukemia and lymphoma PDXs that undergo orthotopic engraftment, called the Public Repository of Xenografts (PRoXe). PRoXe includes all de-identified information relevant to the primary specimens and the PDXs derived from them. Using this repository, we demonstrate that large studies of acute leukemia PDXs that mimic human randomized clinical trials can characterize drug efficacy and generate transcriptional, functional, and proteomic biomarkers in both treatment-naive and relapsed/refractory disease
Diving into the vertical dimension of elasmobranch movement ecology
Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first global synthesis of vertical habitat use by elasmobranchs from data obtained by deployment of 989 biotelemetry tags on 38 elasmobranch species. Elasmobranchs displayed high intra- and interspecific variability in vertical movement patterns. Substantial vertical overlap was observed for many epipelagic elasmobranchs, indicating an increased likelihood to display spatial overlap, biologically interact, and share similar risk to anthropogenic threats that vary on a vertical gradient. We highlight the critical next steps toward incorporating vertical movement into global management and monitoring strategies for elasmobranchs, emphasizing the need to address geographic and taxonomic biases in deployments and to concurrently consider both horizontal and vertical movements
Georeferenced database generation with the purpose of hydrologic molding in reservoirs of the hydrographic basin of Jaguaribe river in the state of Ceará, Brazil
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