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Biomarkers of Inflammation and Fibrosis in Kawasaki Disease Patients Years After Initial Presentation With Low Ejection Fraction.
Background Coronary artery aneurysms and myocarditis are well-recognized complications of Kawasaki disease (KD) but no systematic evaluation of the consequences of myocarditis has been performed in the subset presenting with low ejection fraction (EF). We postulated that more severe myocardial inflammation as evidenced by low EF during the acute phase could lead to late myocardial fibrosis. Methods and Results We measured the carboxyterminal propeptide of procollagen type I (PIPC), soluble suppressor of tumorigenicity 2, galectin-3 (Gal-3), growth-differentiation factor-15, and calprotectin by ELISA in late convalescent blood samples from 16 KD patients who had an EF ≤55% on their initial echocardiogram. Results were compared with samples from sex- and age-matched KD patients with initial EF >60%. In the univariate analysis, the median Gal-3 and PIPC levels in the low EF group were significantly higher than those in the normal EF group (Gal-3: low EF 6.216 versus normal EF 4.976 mg/dL P=0.038, PIPC: low EF 427.4 versus normal EF 265.2 mg/dL, P=0.01). In a multivariable analysis, there were significant differences for Gal-3 and PIPC levels between the low and normal EF groups, adjusting for age, sex, and worst z score. Conclusions Convalescent KD patients with a history of low EF during the acute illness had significantly elevated levels of Gal-3 and PIPC when compared with matched-control KD patients with normal EF. These findings raise concern for myocardial fibrosis as a potential late sequela of the more severe myocarditis experienced by a subset of KD patients during the acute phase
Comment on Reparametrization Invariance of Quark-Lepton Complementarity
We study the complementarity between quark and lepton mixing angles (QLC),
the sum of an angle in quark mixing and the corresponding angle in lepton
mixing is . Experimentally in the standard PDG parametrization, two such
relations exist approximately. These QLC relations are accidental which only
manifest themselves in the PDG parametrization. We propose reparametrization
invariant expressions for the complementarity relations in terms of the
magnitude of the elements in the quark and lepton mixing matrices. In the exact
QLC limit, it is found that and . Expressions with deviations
from exact complementarity are obtained. Implications of these relations are
also discussed.Comment: 5 pages and 1 figure. Implications for recent Daya-Bay neutrino data
on theta_{13} discusse
Systematic search for successful lepton mixing patterns with nonzero theta_13
We perform a systematic search for simple but viable lepton mixing patterns.
Our main criterion is that the mixing matrix can be parameterized by three
rotation angles, which are simple fractions of pi. These simple rotation angles
possess exact expressions for their sines and cosines, and often arise in the
flavor symmetry models. All possible parameterizations of the mixing matrix are
taken into account. In total, twenty successful mixing patterns are found to be
consistent with the latest neutrino oscillation data (including the recent T2K
results) in the CP conserving case, whereas fifteen mixing patterns are allowed
in the maximal CP violating case. Potential radiative corrections to the
constant mixing patterns are also calculated by solving the renormalization
group equations.Comment: 10 pages, 4 figures, 2 tables; version to be published in Nuclear
Physics
Single-Particle Spin-Orbit Strengths of the Nucleon and Hyperons by SU6 Quark-Model
The quark-model hyperon-nucleon interaction suggests an important
antisymmetric spin-orbit component. It is generated from a color analogue of
the Fermi-Breit interaction dominating in the one-gluon exchange process
between quarks. We discuss the strength S_B of the single-particle spin-orbit
potential, following the Scheerbaum's prescription. Using the SU6 quark-model
baryon-baryon interaction which was recently developed by the Kyoto-Niigata
group, we calculate NN, Lambda N and Sigma N G-matrices in symmetric nuclear
matter and apply them to estimate the strength S_B. The ratio of S_B to the
nucleon strength S_N =~ -40 MeV*fm^5 is (S_Lambda)/(S_N) =~ 1/5 and
(S_Sigma)/(S_N) =~ 1/2 in the Born approximation. The G-matrix calculation of
the model FSS modifies S_Lambda to (S_Lambda)/(S_N) =~ 1/12. For S_N and
S_Sigma, the effect of the short-range correlation is comparatively weak
against meson-exchange potentials with a short-range repulsive core. The
significant reduction of the Lambda single-particle potential arises from the
combined effect of the antisymmetric LS force, the flavor-symmetry breaking
originating from the strange to up-down quark-mass difference, as well as the
effect of the short-range correlation. The density dependence of S_B is also
examined.Comment: 26 page
Relatively large theta13 and nearly maximal theta23 from the approximate S3 symmetry of lepton mass matrices
We apply the permutation symmetry S_3 to both charged-lepton and neutrino
mass matrices, and suggest a useful symmetry-breaking scheme, in which the
flavor symmetry is explicitly broken down via S_3 -> Z_3 -> nothing in the
charged-lepton sector and via S_3 -> Z_2 -> nothing in the neutrino sector.
Such a two-stage breaking scenario is reasonable in the sense that both Z_3 and
Z_2 are the subgroups of S_3, while Z_3 and Z_2 only have a trivial subgroup.
In this scenario, we can obtain a relatively large value of the smallest
neutrino mixing angle, e.g., theta_{13} ~ 9^\circ, which is compatible with the
recent result from T2K experiment and will be precisely measured in the ongoing
Double Chooz and Daya Bay reactor neutrino experiments. Moreover, the maximal
atmospheric mixing angle theta_{23} ~ 45^\circ can also be obtained while the
best-fit value of solar mixing angle theta_{12} ~ 34^\circ is assumed, which
cannot be achieved in previous S_3 symmetry models.Comment: 15 pages, no figures, minor changes, matches the published versio
Principal series of finite subgroups of SU(3)
We attempt to give a complete description of the "exceptional" finite
subgroups Sigma(36x3), Sigma(72x3) and Sigma(216x3) of SU(3), with the aim to
make them amenable to model building for fermion masses and mixing. The
information on these groups which we derive contains conjugacy classes, proper
normal subgroups, irreducible representations, character tables and tensor
products of their three-dimensional irreducible representations. We show that,
for these three exceptional groups, usage of their principal series, i.e.
ascending chains of normal subgroups, greatly facilitates the computations and
illuminates the relationship between the groups. As a preparation and testing
ground for the usage of principal series, we study first the dihedral-like
groups Delta(27) and Delta(54) because both are members of the principal series
of the three groups discussed in the paper.Comment: 43 pages, no figures; typos corrected, clarifications and references
added, version matches publication in J. Phys.
TFH Mixing Patterns, Large and Flavor Symmetry
We perform a comprehensive analysis of the Toorop-Feruglio-Hagedorn (TFH)
mixing patterns within the family symmetry . The general neutrino
mass matrix for the TFH mixing and its symmetry properties are investigated.
The possible realizations of the TFH mixing in are analyzed in the
minimalist approach. We propose two dynamical models which produce the TFH
mixing patterns at leading order. The full flavor symmetries are
and
respectively. The next to leading order terms introduce corrections of order
to the three mixing angles in both models. The allowed mixing
patterns are studied under the condition that the Klein four subgroups and the
cyclic subgroups with are preserved in the neutrino and the
charged lepton sector respectively. We suggest that the deformed tri-bimaximal
mixing is a good leading order approximation to understanding a largish reactor
angle.Comment: 43 pages, 2 figure
Trimaximal neutrino mixing from vacuum alignment in A4 and S4 models
Recent T2K results indicate a sizeable reactor angle theta_13 which would
rule out exact tri-bimaximal lepton mixing. We study the vacuum alignment of
the Altarelli-Feruglio A4 family symmetry model including additional flavons in
the 1' and 1" representations and show that it leads to trimaximal mixing in
which the second column of the lepton mixing matrix consists of the column
vector (1,1,1)^T/sqrt{3}, with a potentially large reactor angle. In order to
limit the reactor angle and control the higher order corrections, we propose a
renormalisable S4 model in which the 1' and 1" flavons of A4 are unified into a
doublet of S4 which is spontaneously broken to A4 by a flavon which enters the
neutrino sector at higher order. We study the vacuum alignment in the S4 model
and show that it predicts accurate trimaximal mixing with approximate
tri-bimaximal mixing, leading to a new mixing sum rule testable in future
neutrino experiments. Both A4 and S4 models preserve form dominance and hence
predict zero leptogenesis, up to renormalisation group corrections.Comment: 24 pages, 2 figures, version to be published in JHE
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