9,773 research outputs found
Gauge-invariant implementation of the Abelian Higgs model on optical lattices
We present a gauge-invariant effective action for the Abelian Higgs model
(scalar electrodynamics) with a chemical potential on a 1+1 dimensional
lattice. This formulation provides an expansion in the hopping parameter
which we test with Monte Carlo simulations for a broad range of the
inverse gauge coupling and small values of the scalar
self-coupling . In the opposite limit of infinitely large ,
the partition function can be written as a traced product of local tensors
which allows us to write exact blocking formulas. Their numerical
implementation requires truncations but there is no sign problem for arbitrary
values of . We show that the time continuum limit of the blocked transfer
matrix can be obtained numerically and, in the limit of infinite
and with a spin-1 truncation, the small volume energy spectrum is identical to
the low energy spectrum of a two-species Bose-Hubbard model in the limit of
large onsite repulsion. We extend this procedure for finite and
derive a spin-1 approximation of the Hamiltonian. It involves new terms
corresponding to transitions among the two species in the Bose-Hubbard model.
We propose an optical lattice implementation involving a ladder structure.Comment: 10 pages, 9 figure
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Endothelial toll-like receptor 4 maintains lung integrity via epigenetic suppression of p16INK4a.
We previously reported that the canonical innate immune receptor toll-like receptor 4 (TLR4) is critical in maintaining lung integrity. However, the molecular mechanisms via which TLR4 mediates its effect remained unclear. In the present study, we identified distinct contributions of lung endothelial cells (Ec) and epithelial cells TLR4 to pulmonary homeostasis using genetic-specific, lung- and cell-targeted in vivo methods. Emphysema was significantly prevented via the reconstituting of human TLR4 expression in the lung Ec of TLR4-/- mice. Lung Ec-silencing of TLR4 in wild-type mice induced emphysema, highlighting the specific and distinct role of Ec-expressed TLR4 in maintaining lung integrity. We also identified a previously unrecognized role of TLR4 in preventing expression of p16INK4a , a senescence-associated gene. Lung Ec-p16INK4a -silencing prevented TLR4-/- induced emphysema, revealing a new functional role for p16INK4a in lungs. TLR4 suppressed endogenous p16INK4a expression via HDAC2-mediated deacetylation of histone H4. These findings suggest a novel role for TLR4 in maintaining of lung homeostasis via epigenetic regulation of senescence-related gene expression
Systematic investigation of the rotational bands in nuclei with using a particle-number conserving method based on a cranked shell model
The rotational bands in nuclei with are investigated
systematically by using a cranked shell model (CSM) with the pairing
correlations treated by a particle-number conserving (PNC) method, in which the
blocking effects are taken into account exactly. By fitting the experimental
single-particle spectra in these nuclei, a new set of Nilsson parameters
( and ) and deformation parameters ( and
) are proposed. The experimental kinematic moments of inertia
for the rotational bands in even-even, odd- and odd-odd nuclei, and the
bandhead energies of the 1-quasiparticle bands in odd- nuclei, are
reproduced quite well by the PNC-CSM calculations. By analyzing the
-dependence of the occupation probability of each cranked Nilsson
orbital near the Fermi surface and the contributions of valence orbitals in
each major shell to the angular momentum alignment, the upbending mechanism in
this region is understood clearly.Comment: 21 pages, 24 figures, extended version of arXiv: 1101.3607 (Phys.
Rev. C83, 011304R); added refs.; added Fig. 4 and discussions; Phys. Rev. C,
in pres
Multi-Mode Online Knowledge Distillation for Self-Supervised Visual Representation Learning
Self-supervised learning (SSL) has made remarkable progress in visual
representation learning. Some studies combine SSL with knowledge distillation
(SSL-KD) to boost the representation learning performance of small models. In
this study, we propose a Multi-mode Online Knowledge Distillation method (MOKD)
to boost self-supervised visual representation learning. Different from
existing SSL-KD methods that transfer knowledge from a static pre-trained
teacher to a student, in MOKD, two different models learn collaboratively in a
self-supervised manner. Specifically, MOKD consists of two distillation modes:
self-distillation and cross-distillation modes. Among them, self-distillation
performs self-supervised learning for each model independently, while
cross-distillation realizes knowledge interaction between different models. In
cross-distillation, a cross-attention feature search strategy is proposed to
enhance the semantic feature alignment between different models. As a result,
the two models can absorb knowledge from each other to boost their
representation learning performance. Extensive experimental results on
different backbones and datasets demonstrate that two heterogeneous models can
benefit from MOKD and outperform their independently trained baseline. In
addition, MOKD also outperforms existing SSL-KD methods for both the student
and teacher models.Comment: Accepted by CVPR 202
A Review of Modeling and Diagnostic Techniques for Eccentricity Fault in Electric Machines
Research on the modeling and fault diagnosis of rotor eccentricities has been conducted during the past two decades. A variety of diagnostic theories and methods have been proposed based on different mechanisms, and there are reviews following either one type of electric machines or one type of eccentricity. Nonetheless, the research routes of modeling and diagnosis are common, regardless of machine or eccentricity types. This article tends to review all the possible modeling and diagnostic approaches for all common types of electric machines with eccentricities and provide suggestions on future research roadmap. The paper indicates that a reliable low-cost non-intrusive real-time online visualized diagnostic method is the trend. Observer-based diagnostic strategies are thought promising for the continued research
Nuclear superfluidity for antimagnetic rotation in Cd and Cd
The effect of nuclear superfluidity on antimagnetic rotation bands in
Cd and Cd are investigated by the cranked shell model with the
pairing correlations and the blocking effects treated by a particle-number
conserving method. The experimental moments of inertia and the reduced
transition values are excellently reproduced. The nuclear superfluidity is
essential to reproduce the experimental moments of inertia. The two-shears-like
mechanism for the antimagnetic rotation is investigated by examining the shears
angle, i.e., the closing of the two proton hole angular momenta, and its
sensitive dependence on the nuclear superfluidity is revealed.Comment: 14 pages, 4 figure
Effects of different nutrient solutions on the acclimatisation of in vitro Caladium plantlets using a simplified hydroponic system
An efficient acclimatisation protocol is critical to improve the survival rate and promote growth of in vitro plantlets. Herein, tissue-cultured plantlets of ‘Red Flash’ caladium (Caladium × hortulanum Birdsey) were treated with deionised water and three nutrient solutions including Japanese garden formula (JG), South China Agriculture University formula B for leafy vegetables (SCAU-B) and Hoagland solution in a simplified hydroponic system under indoor environmental conditions. The results showed that all the plantlets survived after 30 days of hydroponic culture, and the three nutrient solutions showed significant positive effects on the plant growth and the content of chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, soluble sugar and soluble protein compared to the deionised water treatment. No significant difference was recorded for the other growth parameters except the average leaf number per plantlet among the nutrient solution treatments. For the analysed physiological parameters, the plantlets treated by SCAU-B contained significantly higher content than those of the Hoagland treatment except the protein content. No significant difference was found between the JG and the SCAU-B treatment except the carotenoid content, and between the JG and the Hoagland treatment except the protein content. The plantlets acclimatised in the nutrient solutions also had a good performance when transferred to plastic pots. These results implied that water alone was not capable of maintaining healthy growth of in vitro caladium plantlets, and hydroponics approach using the three nutrient solutions could be a feasible method for acclimatisation of the plantlets
Rotation and alignment of high- orbitals in transfermium nuclei
The structure of nuclei with is investigated systematically by the
Cranked Shell Model (CSM) with pairing correlations treated by a
Particle-Number Conserving (PNC) method. In the PNC method, the particle number
is conserved and the Pauli blocking effects are taken into account exactly. By
fitting the experimental single-particle spectra in these nuclei, a new set of
Nilsson parameters ( and ) is proposed. The experimental kinematic
moments of inertia and the band-head energies are reproduced quite well by the
PNC-CSM calculations. The band crossing, the effects of high- intruder
orbitals and deformation are discussed in detail.Comment: To appear in the Proceedings of the International Nuclear Physics
Conference (INPC2013), June 2-7, 2013, Florence, Ital
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