170 research outputs found
Deformed Galilei symmetry
A particular deformation of central extended Galilei group is considered. It
is shown that the deformation influences the rules of constructing the composed
systems while one particle states remain basically unaffected. In particular
the mass appeared to be non additive.Comment: 14 pages LaTeX2e fil
Notes on the morphology of the tricuspid valve in the adult human heart
Rapid progress in the field of interventional cardiology has caused research in
the field of morphometry of the heart to be in constant demand [7–10, 12]. In
this study, performed on a group of 75 adult human hearts, the authors have
attempted to assess the form and number of the main and accessory cusps in
the tricuspid valve. We have classified particular forms into 8 groups, depending
on the number of cusps and we have divided the cusps into 3 main groups,
depending on the support of the chordae tendineae
Basic axes of human heart in correlation with heart mass and right ventricular wall thickness
A comparison of the data published in anatomy textbooks and anthropological
tables does not reveal any change in basic heart dimensions during the period since
the beginning of the 20th century to nowadays. However, normal values of many
other parameters have changed up to 30% over the same period. These changes
may be caused by the acceleration phenomenon or the extension of average lifespan.
The progress of laboratory medicine methodology permitted the introduction of
new biochemical tests in myocardial infarct diagnosis, such as myoglobin and
troponins T and I measurement, as well as better understanding of cardiac metabolism.
Parameters describing the direction and intensity of metabolic changes
are substrate extraction and metabolic equilibrium. The expression describing
metabolic equilibrium contains heart mass value. Therefore, as studying heart
mass in vivo is not possible, it may be important to study it in vitro.
The study was performed on a group of 107 formalin-fixed human hearts. The
organs came from adults of both sexes: 30 women and 77 men, aged 18 to
90 years. None of the hearts carried signs of macroscopic developmental abnormalities
or pathologic changes
Jordanian Quantum Deformations of D=4 Anti-de-Sitter and Poincare Superalgebras
We consider a superextension of the extended Jordanian twist, describing
nonstandard quantization of anti-de-Sitter () superalgebra in
the form of Hopf superalgebra. The super-Jordanian twisting function and
corresponding basic coproduct formulae for the generators of are
given in explicit form. The nonlinear transformation of the classical
superalgebra basis not modifying the defining algebraic relations but
simplifying coproducts and antipodes is proposed. Our physical application is
to interpret the new super-Jordanian deformation of superalgebra as
deformed D=4 supersymmetries. Subsequently we perform suitable
contraction of quantum Jordanian superalgebra and obtain new
-deformation of D=4 Poincare superalgebra, with the bosonic sector
describing the light cone -deformation of Poincare symmetries.Comment: LaTeX,13 pages, comments and references added, to be published in
Eur.Phys.J.
Proper holomorphic mappings between symmetrized ellipsoids
We characterize the existence of proper holomorphic mappings in the special
class of bounded -balanced domains in , called the
symmetrized ellipsoids. Using this result we conclude that there are no
non-trivial proper holomorphic self-mappings in the class of symmetrized
ellipsoids. We also describe the automorphism groupof these domains.Comment: 10 pages, some modification
On the unitarity of higher-dervative and nonlocal theories
We consider two simple models of higher-derivative and nonlocal quantu
systems.It is shown that, contrary to some claims found in literature, they can
be made unitary.Comment: 8 pages, no figure
Septomarginal trabecula and anterior papillary muscle in primate hearts: developmental issues
The septomarginal trabecula is present in all human hearts as well as in thehearts of other primates. It usually connects the interventricular septum withthe anterior papillary muscle, although there are many variations in how this isachieved. The object of the analyses was to estimate the bilateral topography ofthe septomarginal trabecula and the anterior papillary muscle in the context ofthe ontogeny and phylogeny of primates. A total of 138 hearts were examinedfrom number of different non-human primates. The presence of the septomarginaltrabecula was confirmed in 94.9% of cases, although not in the hearts ofLemur varius. Four configurations could be distinguished by defining the locationof the septomarginal trabecula and its relation to the anterior papillary muscle.For the hearts of the Strepsirrhini and the majority of Platyrrhini neither structurewas related, whereas in all examined representatives of Hominoidea they hadfused and created morphologically varying forms. On the basis of these results,a concept was developed for the sequence of changes which the topography ofthe septomarginal trabecula and the anterior papillary muscle undergo duringontogeny and phylogeny
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