2,744 research outputs found
Exact dynamical AdS black holes and wormholes with a Klein-Gordon field
We present several classes of exact solutions in the Einstein-Klein-Gordon
system with a cosmological constant. The spacetime has spherical, plane, or
hyperbolic symmetry and the higher-dimensional solutions are obtained in a
closed form only in the plane symmetric case. Among them, the class-I solution
represents an asymptotically locally anti-de Sitter (AdS) dynamical black hole
or wormhole. In four and higher dimensions, the generalized Misner-Sharp
quasi-local mass blows up at AdS infinity, inferring that the spacetime is only
locally AdS. In three dimensions, the scalar field becomes trivial and the
solution reduces to the BTZ black hole.Comment: 11 pages, 2 figures, 2 tables; v2, results strengthened, argument on
trapping horizon corrected; v3, argument on locally AdS property added,
accepted for publication in Physical Review
Generalized Bayesian Record Linkage and Regression with Exact Error Propagation
Record linkage (de-duplication or entity resolution) is the process of
merging noisy databases to remove duplicate entities. While record linkage
removes duplicate entities from such databases, the downstream task is any
inferential, predictive, or post-linkage task on the linked data. One goal of
the downstream task is obtaining a larger reference data set, allowing one to
perform more accurate statistical analyses. In addition, there is inherent
record linkage uncertainty passed to the downstream task. Motivated by the
above, we propose a generalized Bayesian record linkage method and consider
multiple regression analysis as the downstream task. Records are linked via a
random partition model, which allows for a wide class to be considered. In
addition, we jointly model the record linkage and downstream task, which allows
one to account for the record linkage uncertainty exactly. Moreover, one is
able to generate a feedback propagation mechanism of the information from the
proposed Bayesian record linkage model into the downstream task. This feedback
effect is essential to eliminate potential biases that can jeopardize resulting
downstream task. We apply our methodology to multiple linear regression, and
illustrate empirically that the "feedback effect" is able to improve the
performance of record linkage.Comment: 18 pages, 5 figure
GTI-space : the space of generalized topological indices
A new extension of the generalized topological indices (GTI) approach is carried out torepresent 'simple' and 'composite' topological indices (TIs) in an unified way. Thisapproach defines a GTI-space from which both simple and composite TIs represent particular subspaces. Accordingly, simple TIs such as Wiener, Balaban, Zagreb, Harary and Randićconnectivity indices are expressed by means of the same GTI representation introduced for composite TIs such as hyper-Wiener, molecular topological index (MTI), Gutman index andreverse MTI. Using GTI-space approach we easily identify mathematical relations between some composite and simple indices, such as the relationship between hyper-Wiener and Wiener index and the relation between MTI and first Zagreb index. The relation of the GTI space with the sub-structural cluster expansion of property/activity is also analysed and some routes for the applications of this approach to QSPR/QSAR are also given
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Air quality investigations of the Sandia National Laboratories Sol se Mete Aerial Cable Facility
The air quality implications of the test and evaluation activities at the Sandia National Laboratories Sol se Mete Aerial Cable Facility are examined. All facets of the activity that affect air quality are considered. Air contaminants produced directly include exhaust products of rocket motors used to accelerate test articles, dust and gas from chemical explosives, and exhaust gases from electricity generators in the test arenas. Air contaminants produced indirectly include fugitive dust and exhaust contaminants from vehicles used to transport personnel and material to the test area, and effluents produced by equipment used to heat the project buildings. Both the ongoing program and the proposed changes in the program are considered. Using a reliable estimate of th maximum annual testing level, the quantities of contaminants released by project activities ar computed either from known characteristics of test items or from EPA-approved emission factors Atmospheric concentrations of air contaminants are predicted using EPA dispersion models. The predicted quantities and concentrations are evaluated in relation to Federal, New Mexico, an Bernalillo County air quality regulations and the human health and safety standards of the American Conference of Governmental Industrial Hygienists
The Effect of Air on Granular Size Separation in a Vibrated Granular Bed
Using high-speed video and magnetic resonance imaging (MRI) we study the
motion of a large sphere in a vertically vibrated bed of smaller grains. As
previously reported we find a non-monotonic density dependence of the rise and
sink time of the large sphere. We find that this density dependence is solely
due to air drag. We investigate in detail how the motion of the intruder sphere
is influenced by size of the background particles, initial vertical position in
the bed, ambient pressure and convection. We explain our results in the
framework of a simple model and find quantitative agreement in key aspects with
numerical simulations to the model equations.Comment: 14 pages, 16 figures, submitted to PRE, corrected typos, slight
change
Progress toward curing HIV infection with hematopoietic cell transplantation.
HIV-1 infection afflicts more than 35 million people worldwide, according to 2014 estimates from the World Health Organization. For those individuals who have access to antiretroviral therapy, these drugs can effectively suppress, but not cure, HIV-1 infection. Indeed, the only documented case for an HIV/AIDS cure was a patient with HIV-1 and acute myeloid leukemia who received allogeneic hematopoietic cell transplantation (HCT) from a graft that carried the HIV-resistant CCR5-∆32/∆32 mutation. Other attempts to establish a cure for HIV/AIDS using HCT in patients with HIV-1 and malignancy have yielded mixed results, as encouraging evidence for virus eradication in a few cases has been offset by poor clinical outcomes due to the underlying cancer or other complications. Such clinical strategies have relied on HIV-resistant hematopoietic stem and progenitor cells that harbor the natural CCR5-∆32/∆32 mutation or that have been genetically modified for HIV-resistance. Nevertheless, HCT with HIV-resistant cord blood remains a promising option, particularly with inventories of CCR5-∆32/∆32 units or with genetically modified, human leukocyte antigen-matched cord blood
Weighted ergodic theorems for Banach-Kantorovich lattice
In the present paper we prove weighted ergodic theorems and multiparameter
weighted ergodic theorems for positive contractions acting on
. Our main tool is the use of methods of
measurable bundles of Banach-Kantorovich lattices.Comment: 11 page
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