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A One Health Approach to Hypertrophic Cardiomyopathy.
Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease in humans and results in significant morbidity and mortality. Research over the past 25 years has contributed enormous insight into this inherited disease particularly in the areas of genetics, molecular mechanisms, and pathophysiology. Our understanding continues to be limited by the heterogeneity of clinical presentations with various genetic mutations associated with HCM. Transgenic mouse models have been utilized especially studying the genotypic and phenotypic interactions. However, mice possess intrinsic cardiac and hemodynamic differences compared to humans and have limitations preventing their direct translation. Other animal models of HCM have been studied or generated in part to overcome these limitations. HCM in cats shows strikingly similar molecular, histopathological, and genetic similarities to human HCM, and offers an important translational opportunity for the study of this disease. Recently, inherited left ventricular hypertrophy in rhesus macaques was identified and collaborative investigations have been conducted to begin to develop a non-human primate HCM model. These naturally-occurring large-animal models may aid in advancing our understanding of HCM and developing novel therapeutic approaches to this disease. This review will highlight the features of HCM in humans and the relevant available and developing animal models of this condition
NMR relaxation and resistivity from rattling phonons in pyrochlore superconductors
We calculate the temperature dependence of NMR relaxation rate and electrical
resistivity for coupling to a local, strongly anharmonic phonon mode. We argue
that the two-phonon Raman process is dominating NMR relaxation. Due to the
strong anharmonicity of the phonon an unusual temperature dependence is found
having a low temperature peak and becoming constant towards higher
temperatures. The electrical resistivity is found to vary like T^2 at low
temperatures and following a sqrt{T} behavior at high temperatures. Both
results are in qualitative agreement with recent observations on
beta-pyrochlore oxide superconductors.Comment: 4 pages, 4 figures; new version with some minor additional
clarifications; accepted for publication in Phys. Rev. Let
Phonon Spectroscopy by Electric Measurements of Coupled Quantum Dots
We propose phonon spectroscopy by electric measurements of the
low-temperature conductance of coupled-quantum dots, specifically employing
dephasing of the quantum electronic transport by the phonons. The setup we
consider consists of a T-shaped double-quantum-dot (DQD) system in which only
one of the dots (dot 1) is connected to external leads and the other (dot 2) is
coupled solely to the first one. For noninteracting electrons, the differential
conductance of such a system vanishes at a voltage located in-between the
energies of the bonding and the anti-bonding states, due to destructive
interference. When electron-phonon (e-ph) on the DQD is invoked, we find that,
at low temperatures, phonon emission taking place on dot 1 does not affect the
interference, while phonon emission from dot 2 suppresses it. The amount of
this suppression, as a function of the bias voltage, follows the effective e-ph
coupling reflecting the phonon density of states and can be used for phonon
spectroscopy.Comment: 9 pages, 6 figure
Density-Matrix Renormalization Group Study of Trapped Imbalanced Fermi Condensates
The density-matrix renormalization group is employed to investigate a
harmonically-trapped imbalanced Fermi condensate based on a one-dimensional
attractive Hubbard model. The obtained density profile shows a flattened
population difference of spin-up and spin-down components at the center of the
trap, and exhibits phase separation between the condensate and unpaired
majority atoms for a certain range of the interaction and population imabalance
. The two-particle density matrix reveals that the sign of the order
parameter changes periodically, demonstrating the realization of the
Fulde-Ferrell-Larkin-Ovchinnikov phase. The minority spin atoms contribute to
the quasi-condensate up to at least . Possible experimental
situations to test our predictions are discussed.Comment: 4 pages, 3 figures; added references; accepted for publication in
Phys. Rev. Let
Nonunitary quantum circuit
A quantum circuit is generalized to a nonunitary one whose constituents are
nonunitary gates operated by quantum measurement. It is shown that a specific
type of one-qubit nonunitary gates, the controlled-NOT gate, as well as all
one-qubit unitary gates constitute a universal set of gates for the nonunitary
quantum circuit, without the necessity of introducing ancilla qubits. A
reversing measurement scheme is used to improve the probability of successful
nonunitary gate operation. A quantum NAND gate and Abrams-Lloyd's nonlinear
gate are analyzed as examples. Our nonunitary circuit can be used to reduce the
qubit overhead needed to ensure fault-tolerant quantum computation.Comment: 19 pages, 6 figures; added a referenc
Einstein--de Haas Effect in Dipolar Bose-Einstein Condensates
The general properties of the order parameter for a dipolar spinor
Bose-Einstein condensate are discussed based on symmetries of interactions. An
initially spin-polarized dipolar condensate is shown to dynamically generate a
non-singular vortex via spin-orbit interactions -- a phenomenon reminiscent of
the Einstein--de Haas effect in ferromagnets.Comment: 4 pages, 4 figures; Final versio
Pressure-induced changes in the optical properties of quasi-one-dimensional -NaVO
The pressure-induced changes in the optical properties of
-NaVO single crystals at room temperature were studied
by polarization-dependent Raman and far-infrared reflectivity measurements
under high pressure. From the changes in the Raman- and infrared-active phonon
modes in the pressure range 9 - 12 GPa a transfer of charge between the
different V sites can be inferred. The importance of electron-phonon coupling
in the low-pressure regime is discussed.Comment: 7 pages, 5 figure
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