101 research outputs found
Effective three-body interactions for bosons in a double-well confinement
When describing the low-energy physics of bosons in a double-well potential
with a high barrier between the wells and sufficiently weak atom-atom
interactions, one can to a good approximation ignore the high energy states and
thereby obtain an effective two-mode model. Here, we show that the regime in
which the two-mode model is valid can be extended by adding an on-site
three-body interaction term and a three-body interaction-induced tunneling term
to the two-mode Hamiltonian. These terms effectively account for virtual
transitions to the higher energy states. We determine appropriate strengths of
the three-body terms by an optimization of the minimal value of the wave
function overlap within a certain time window. Considering different initial
states with three or four atoms, we find that the resulting model accurately
captures the dynamics of the system for parameters where the two-mode model
without the three-body terms is poor. We also investigate the dependence of the
strengths of the three-body terms on the barrier height and the atom-atom
interaction strength. The optimal three-body interaction strengths depend on
the initial state of the system.Comment: 8 pages, 6 figure
Local Unitary Classification of Arbitrary Dimensional Multipartite Pure States
We propose a practical entanglement classification scheme for general
multipartite pure states in arbitrary dimensions under local unitary
equivalence by exploiting the high order singular value decomposition technique
and local symmetries of the states. By virtue of this scheme, the method of
determining the local unitary equivalence of -qubit states proposed by Kraus
is extended to the case for arbitrary dimensional multipartite states.Comment: 10 pages; published in Phys. Rev. Let
miRNAs Reshape Immunity and Inflammatory Responses in Bacterial Infection
Pathogenic bacteria cause various infections worldwide, especially in immunocompromised and other susceptible individuals, and are also associated with high infant mortality rates in developing countries. MicroRNAs (miRNAs), small non-coding RNAs with evolutionarily conserved sequences, are expressed in various tissues and cells that play key part in various physiological and pathologic processes. Increasing evidence implies roles for miRNAs in bacterial infectious diseases by modulating inflammatory responses, cell penetration, tissue remodeling, and innate and adaptive immunity. This review highlights some recent intriguing findings, ranging from the correlation between aberrant expression of miRNAs with bacterial infection progression to their profound impact on host immune responses. Harnessing of dysregulated miRNAs in bacterial infection may be an approach to improving the diagnosis, prevention and therapy of infectious diseases
Dynamics of quasiholes and quasiparticles at the edges of small lattices
We study quench dynamics of bosonic fractional quantum Hall systems in small
lattices with cylindrical boundary conditions and low particle density. The
states studied have quasiholes or quasiparticles relative to the bosonic
Laughlin state at half filling. Pinning potentials are placed at edge sites (or
sites close to the edges) and are then turned off. Because the edges of
fractional quantum Hall systems host chiral edge modes, we expect chiral
dynamics, with motion in one direction for positive potentials pinning
quasiholes, and motion in the other direction for negative potentials pinning
quasiparticles. We numerically show that chiral motion of the density
distribution is observed and robust for the case with positive potentials
(quasiholes), but that there is no noticeable chiral motion for negative
potentials (quasiparticles). The comparison of the numerical ground states with
model lattice Laughlin wavefunctions suggests that both positive and negative
potentials do create and pin anyons that are not necessarily well-separated on
small lattices. Initializing the dynamics with the model state also shows the
lack of chiral dynamics of quasiparticles. Our results suggest that, in small
lattices with low particle density, quasiparticles are strongly adversely
affected in dynamical processes, whereas quasiholes are dynamically robust.Comment: 13 pages, 10 figure
Global optimization for quantum dynamics of few-fermion systems
Quantum state preparation is vital to quantum computation and quantum
information processing tasks. In adiabatic state preparation, the target state
is theoretically obtained with nearly perfect fidelity if the control parameter
is tuned slowly enough. As this, however, leads to slow dynamics, it is often
desirable to be able to do processes faster. In this work, we employ two global
optimization methods to estimate the quantum speed limit for few-fermion
systems confined in a one-dimensional harmonic trap. Such systems can be
produced experimentally in a well controlled manner. We determine the optimized
control fields and achieve a reduction in the ramping time of more than a
factor of four compared to linear ramping. We also investigate how robust the
fidelity is to small variations of the control fields away from the optimized
shapes.Comment: 8 pages, 5 figures, 1 tabl
3D LiDAR Aided GNSS NLOS Mitigation for Reliable GNSS-RTK Positioning in Urban Canyons
GNSS and LiDAR odometry are complementary as they provide absolute and
relative positioning, respectively. Their integration in a loosely-coupled
manner is straightforward but is challenged in urban canyons due to the GNSS
signal reflections. Recent proposed 3D LiDAR-aided (3DLA) GNSS methods employ
the point cloud map to identify the non-line-of-sight (NLOS) reception of GNSS
signals. This facilitates the GNSS receiver to obtain improved urban
positioning but not achieve a sub-meter level. GNSS real-time kinematics (RTK)
uses carrier phase measurements to obtain decimeter-level positioning. In urban
areas, the GNSS RTK is not only challenged by multipath and NLOS-affected
measurement but also suffers from signal blockage by the building. The latter
will impose a challenge in solving the ambiguity within the carrier phase
measurements. In the other words, the model observability of the ambiguity
resolution (AR) is greatly decreased. This paper proposes to generate virtual
satellite (VS) measurements using the selected LiDAR landmarks from the
accumulated 3D point cloud maps (PCM). These LiDAR-PCM-made VS measurements are
tightly-coupled with GNSS pseudorange and carrier phase measurements. Thus, the
VS measurements can provide complementary constraints, meaning providing
low-elevation-angle measurements in the across-street directions. The
implementation is done using factor graph optimization to solve an accurate
float solution of the ambiguity before it is fed into LAMBDA. The effectiveness
of the proposed method has been validated by the evaluation conducted on our
recently open-sourced challenging dataset, UrbanNav. The result shows the fix
rate of the proposed 3DLA GNSS RTK is about 30% while the conventional GNSS-RTK
only achieves about 14%. In addition, the proposed method achieves sub-meter
positioning accuracy in most of the data collected in challenging urban areas
Transient receptor potential channel 1 deficiency impairs host defense and proinflammatory responses to bacterial infection by regulating protein kinase Cα signaling
Transient receptor potential channel 1 (TRPC1) is a nonselective cation channel that is required for Ca2+ homeostasis necessary for cellular functions. However, whether TRPC1 is involved in infectious disease remains unknown. Here, we report a novel function for TRPC1 in host defense against Gram-negative bacteria. TRPC1-/- mice exhibited decreased survival, severe lung injury, and systemic bacterial dissemination upon infection. Furthermore, silencing of TRPC1 showed decreased Ca2+ entry, reduced proinflammatory cytokines, and lowered bacterial clearance. Importantly, TRPC1 functioned as an endogenous Ca2+ entry channel critical for proinflammatory cytokine production in both alveolar macrophages and epithelial cells. We further identified that bacterium-mediated activation of TRPC1 was dependent on Toll-like receptor 4 (TLR4), which induced endoplasmic reticulum (ER) store depletion. After activation of phospholipase Cγ (PLC-γ), TRPC1 mediated Ca2+ entry and triggered protein kinase Cα (PKC-α) activity to facilitate nuclear translocation of NF-kB/Jun N-terminal protein kinase (JNK) and augment the proinflammatory response, leading to tissue damage and eventually mortality. These findings reveal that TRPC1 is required for host defense against bacterial infections through the TLR4-TRPC1-PKCγ signaling circuit.Fil: Zhou, Xikun. University Of North Dakota; Estados Unidos. West China Hospital Of Sichuan University; ChinaFil: Ye, Yan. University Of North Dakota; Estados UnidosFil: Sun, Yuyang. University Of North Dakota; Estados UnidosFil: Li, Xuefeng. West China Hospital Of Sichuan University; China. University Of North Dakota; Estados UnidosFil: Wang, Wenxue. University Of North Dakota; Estados UnidosFil: Privratsky, Breanna. University Of North Dakota; Estados UnidosFil: Tan, Shirui. University Of North Dakota; Estados UnidosFil: Zhou, Zongguang. West China Hospital Of Sichuan University; ChinaFil: Huang, Canhua. West China Hospital Of Sichuan University; ChinaFil: Wei, Yu-Quan. West China Hospital Of Sichuan University; ChinaFil: Birnbaumer, Lutz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. National Institute Of Environmental Health Sciences; Estados UnidosFil: Singh, Brij B.. University Of North Dakota; Estados UnidosFil: Wu, Min. University Of North Dakota; Estados Unido
The Parametric Symmetry and Numbers of the Entangled Class of 2 \times M \times N System
We present in the work two intriguing results in the entanglement
classification of pure and true tripartite entangled state of under stochastic local operation and classical communication. (i) the
internal symmetric properties of the nonlocal parameters in the continuous
entangled class; (ii) the analytic expression for the total numbers of the true
and pure entangled class states. These properties help
people to know more of the nature of the entangled system.Comment: 12 pages, 5 figure
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