3,654 research outputs found
Vortex equations in abelian gauged sigma-models
We consider nonlinear gauged sigma-models with Kahler domain and target. For
a special choice of potential these models admit Bogomolny (or self-duality)
equations -- the so-called vortex equations. We find the moduli space and
energy spectrum of the solutions of these equations when the gauge group is a
torus T^n, the domain is compact, and the target is C^n or CP^n. We also obtain
a large family of solutions when the target is a compact Kahler toric manifold.Comment: v2: 60 pages, more details than in CMP versio
The quantum equivariant cohomology of toric manifolds through mirror symmetry
Using mirror symmetry as described by Hori and Vafa, we compute the quantum
equivariant cohomology ring of toric manifolds. This ring arises naturally in
topological gauged sigma-models and is related to the Hamiltonian Gromov-Witten
invariants of the target manifold.Comment: 13 pages; v2: added comments and references, published versio
Experimental observation of a complex periodic window
The existence of a special periodic window in the two-dimensional parameter
space of an experimental Chua's circuit is reported. One of the main reasons
that makes such a window special is that the observation of one implies that
other similar periodic windows must exist for other parameter values. However,
such a window has never been experimentally observed, since its size in
parameter space decreases exponentially with the period of the periodic
attractor. This property imposes clear limitations for its experimental
detection.Comment: 4.2 pages, 4 figure
A spiral structure in the disk of EX Draconis on the rise to outburst maximum
We report on the R-band eclipse mapping analysis of high-speed photometry of
the dwarf nova EX Dra on the rise to the maximum of the November 1995 outburst.
The eclipse map shows a one-armed spiral structure of ~180 degrees in azimuth,
extending in radius from R ~0.2 to 0.43 R_{L1} (where R_{L1} is the distance
from the disk center to the inner Lagrangian point), that contributes about 22
per cent of the total flux of the eclipse map. The spiral structure is
stationary in a reference frame co-rotating with the binary and is stable for a
timescale of at least 5 binary orbits. The comparison of the eclipse maps on
the rise and in quiescence suggests that the outbursts of EX Dra may be driven
by episodes of enhanced mass-transfer from the secondary star. Possible
explanations for the nature of the spiral structure are discussed.Comment: To appear in the Astrophysical Journal Letters; 8 pages, 2 figures;
coded with AAS latex styl
Bronquiolite: Avanços Recentes
A bronquiolite e a infecção respiratória aguda das vias aéreas inferiores mais frequente em criançascom idade inferior a 24 meses, responsável por morbimortalidade significativa, incluindo complicações
frequentes na fase aguda e a longo prazo. A
heterogeneidade da abordagem desta patologia e a dificuldade em reduzir o seu peso nos indices de saúde pública, vem motivando investigação contínua e legitimou a publicação recente (2006) pela
Academia Americana de Pediatria (AAP) de normas de actuação, chamando-se a atenção para os resultados de uma metanálise realizada pela Cochrane Collaboration e para a existência de diversos fenotipos
de apresentação c1ínica.Os autores abordam alguns aspectos epidemiológicos,
c1ínicos (nomeadamente as complicações)
e, sobretudo, de terapêutica, com base em estudos recentes, elaborando uma proposta concretade actuação
Tilted excitation implies odd periodic resonances
This work was supported by the Brazilian agencies FAPESP and CNPq. MSB also acknowledges the Engineering and Physical Sciences Research Council grant Ref. EP/I032606/1. GID thanks Felipe A. C. Pereira for fruitful discussions.Peer reviewedPostprin
Structured and unstructured data integration with electronic medical records
Medicine is a field with high volatility of changes. Everyday new discoveries and procedures are tested with the sole goal of providing a better-quality life to patients. With the evolution of computer science, multiple fields saw an increase of productivity and solutions that could be implemented. More specifically, in medicine new techniques started being tested in order to understand how the systems and practices used can reach higher performances, while maintaining the predefined high standards of quality. For many years data generated in hospital was collected and stored yet few tools were implemented to extract knowledge or any type of advantage. One of the areas that successfully implemented in medicine was the usage of data processing tools and techniques to further extract information regarding the high abundance of data generated in a daily basis, in this field of work. This data can be stored in different ways which leads to multiple approaches on how to deals with it. The sole purpose of this paper is to give an overview of some case studies where structured and unstructured data was used, joint and separately and the value of it.info:eu-repo/semantics/publishedVersio
Revision of the Portuguese catalog of tsunamis
Catastrophic tsunamis are described in historical sources for all regions around the Gulf of Cadiz, at least since 60 BC. Most of the known events are associated with moderate to large earthquakes and among them the better studied is 1 November 1755. We present here a review of the events which effects, on the coasts of the Portuguese mainland and Madeira Island, are well described in historical documents or have been measured by tide gauges since the installation of these instruments. For a few we include new relevant information for the assessment of the tsunami generation or effects, and we discard events that are included in existing compilations but are not supported by quality historical sources or instrumental records. We quote the most relevant quantitative descriptions of tsunami effects on the Portuguese coast, including in all pertinent cases a critical review of the coeval sources, to establish a homogenous event list. When available, instrumental information is presented. We complement all this information with a summary of the conclusions established by paleo-tsunami research
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