70 research outputs found
Prognostic implications of left ventricular hypertrophy
Left ventricular hypertrophy (LVH) was one of the earliest studied echocardiographic characteristics of the left ventricle. As the myriad of measurable metrics has multiplied over recent years, this reliable and relevant variable can often be overlooked. In this paper, we discuss appropriate techniques for accurate analysis, underlying pathophysiology, and the contributions from various risk factors. The prognostic implications of LVH on stroke, serious arrhythmias, and sudden cardiac death are reviewed. Finally, we examine the effect of therapy to reduce LVH and the resultant clinical outcomes. (C) 2018 Elsevier Inc. All rights reserved
Exact Cosmological Solutions of Gravitational Theories
A global picture is drawn tying together most exact cosmological solutions of
gravitational theories in four or more spacetime dimensions.Comment: 11 latex article style page
Quantum gauge models without classical Higgs mechanism
We examine the status of massive gauge theories, such as those usually
obtained by spontaneous symmetry breakdown, from the viewpoint of causal
(Epstein-Glaser) renormalization. The BRS formulation of gauge invariance in
this framework, starting from canonical quantization of massive (as well as
massless) vector bosons as fundamental entities, and proceeding perturbatively,
allows one to rederive the reductive group symmetry of interactions, the need
for scalar fields in gauge theory, and the covariant derivative. Thus the
presence of higgs particles is explained without recourse to a
Higgs(-Englert-Brout-Guralnik-Hagen-Kibble) mechanism. Along the way, we dispel
doubts about the compatibility of causal gauge invariance with grand unified
theories.Comment: 20 pages in two-column EPJC format, shortened version accepted for
publication. For more details, consult version
Phenomenology of the Interplay between IR-Improved DGLAP-CS Theory and NLO ME Matched Parton Shower MC Precision
We present the current status of the application of our approach of {\it
exact} amplitude-based resummation in quantum field theory to precision QCD
calculations, by realistic MC event generator methods, as needed for precision
LHC physics.In this ongoing program of research, we discuss recent results as
they relate to the interplay of the attendant IR-Improved DGLAP-CS theory of
one of us and the precision of exact NLO matrix element matched parton shower
MC's in the Herwig6.5 environment in relation to recent LHC experimental
observations. There continues to be reason for optimism in the attendant
comparison of theory and experiment.Comment: 11 pages, 3 figures; now 12 pages, 4 figures -- explanatory material
added and title changed for publication in Phys. Lett.
Status and Prospects of Top-Quark Physics
The top quark is the heaviest elementary particle observed to date. Its large
mass of about 173 GeV/c^2 makes the top quark act differently than other
elementary fermions, as it decays before it hadronises, passing its spin
information on to its decay products. In addition, the top quark plays an
important role in higher-order loop corrections to standard model processes,
which makes the top quark mass a crucial parameter for precision tests of the
electroweak theory. The top quark is also a powerful probe for new phenomena
beyond the standard model. During the time of discovery at the Tevatron in 1995
only a few properties of the top quark could be measured. In recent years,
since the start of Tevatron Run II, the field of top-quark physics has changed
and entered a precision era. This report summarises the latest measurements and
studies of top-quark properties and gives prospects for future measurements at
the Large Hadron Collider (LHC).Comment: 76 pages, 35 figures, submitted to Progress in Particle and Nuclear
Physic
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