3,629 research outputs found
Lie bialgebra structures on the twisted Heisenberg-Virasoro algebra
In this paper we investigate Lie bialgebra structures on the twisted
Heisenberg-Virasoro algebra. With the classifications of Lie bialgebra
structures on the Virasoro algebra, we determined such structures on the
twisted Heisenberg-Virasoro algebra. Moreover, some general and useful results
are obtained. With our methods and results we also can easily to determine such
structures on some Lie algebras related to the twisted Heisenberg-Virasoro
algebra.Comment: Latex 18page. arXiv admin note: text overlap with arXiv:0901.133
A note on the proof of magnetic flux quantization from ODLRO
It is noticed that the excellent proof of the connection of magnetic flux
quantization and off-diagonal long range order (ODLRO) presented recently by
Nieh, Su and Zhao suffers from an imperfection, namely, the f-factors in the
case of finite translation do not satisfy , which was employed
in the proof. A corrected proof is proposed to remedy this point.Comment: 6 pages, LATEX, no figure
A Unified Query-based Paradigm for Camouflaged Instance Segmentation
Due to the high similarity between camouflaged instances and the background,
the recently proposed camouflaged instance segmentation (CIS) faces challenges
in accurate localization and instance segmentation. To this end, inspired by
query-based transformers, we propose a unified query-based multi-task learning
framework for camouflaged instance segmentation, termed UQFormer, which builds
a set of mask queries and a set of boundary queries to learn a shared composed
query representation and efficiently integrates global camouflaged object
region and boundary cues, for simultaneous instance segmentation and instance
boundary detection in camouflaged scenarios. Specifically, we design a composed
query learning paradigm that learns a shared representation to capture object
region and boundary features by the cross-attention interaction of mask queries
and boundary queries in the designed multi-scale unified learning transformer
decoder. Then, we present a transformer-based multi-task learning framework for
simultaneous camouflaged instance segmentation and camouflaged instance
boundary detection based on the learned composed query representation, which
also forces the model to learn a strong instance-level query representation.
Notably, our model views the instance segmentation as a query-based direct set
prediction problem, without other post-processing such as non-maximal
suppression. Compared with 14 state-of-the-art approaches, our UQFormer
significantly improves the performance of camouflaged instance segmentation.
Our code will be available at https://github.com/dongbo811/UQFormer.Comment: This paper has been accepted by ACM MM202
Chronic Stress Facilitates the Development of Deep Venous Thrombosis
The increasing pressure of modern social life intensifies the impact of stress on the development of cardiovascular diseases, which include deep venous thrombosis (DVT). Renal sympathetic denervation has been applied as one of the clinical approaches for the treatment of drug-resistant hypertension. In addition, the close relationship between oxidative stress and cardiovascular diseases has been well documented. The present study is designed to explore the mechanism by which the renal sympathetic nerve system and the oxidative stress affect the blood coagulation system in the development of DVT. Chronic foot shock model in rats was applied to mimic a state of physiological stress similar to humans. Our results showed that chronic foot shock procedure could promote DVT which may be through the activation of platelets aggregation. The aggravation of DVT and activation of platelets were alleviated by renal sympathetic denervation or antioxidant (Tempol) treatment. Concurrently, the denervation treatment could also reduce the levels of circulating oxidation factors in rats. These results demonstrate that both the renal sympathetic nerve system and the oxidative stress contribute to the development of DVT in response to chronic stress, which may provide novel strategy for treatment of clinic DVT patients
[3,5-Bis(benzyloxy)phenyl]methanol
In the title compound, C21H20O3, the two terminal phenyl rings are each approximately perpendicular to the central benzene ring, making dihedral angles of 84.40 (16) and 75.12 (15)°. The H atom of the hydroxy group is disordered over two positions with equal occupancies. The molecules are linked by O—H⋯O hydrogen bonds, forming a chain along the a axis
Quench of a Single-Layer ReBCO CORC Cable with Non-Uniform Terminal Contact Resistance
ReBCO conductor-on-round-core (CORC) cable has become a promising candidate for high temperature superconducting (HTS) power applications, due to its great mechanical strength, high current carrying capacity, high flexibility, and low ac losses. However, ReBCO coated conductors are at risk of quenching, which significantly affects the thermal stability and reliability of the CORC cable. Three-dimensional (3-D) numerical study on the quench behavior of the CORC cable remains a challenge, for its complex geometry is difficult to cope with. In this paper, a 3-D time-dependent multi-physics quench model based on the T-A formulation has been developed. Three modules are coupled in this model; the T-A formulation model, a heat transfer model, and an equivalent circuit model. The quench behavior of a single-layer ReBCO CORC cable with non-uniform terminal contact resistances has been studied, when a hotspot is imposed on one of the tapes to induce a local quench. Results show that, the CORC cable has the highest MQE; in other words, it is the most stable situation, when the hotspot-induced quench occurs on the tape with the middle value of terminal contact resistance
Observing parity-time symmetry in diffusive systems
Phase modulation has scarcely been mentioned in diffusive systems since the
diffusion process does not carry momentum like waves. Recently, the
non-Hermitian physics provides a new perspective for understanding diffusion
and shows prospects in the phase regulation of heat flow, for example, the
discovery of anti-parity-time (APT) symmetry in diffusive systems. The precise
control of thermal phase however remains elusive hitherto and can hardly be
realized in APT-symmetric thermal systems due to the existence of phase
oscillation. Here we construct the counterpart of APT-symmetric diffusive
systems, i.e., PT-symmetric diffusive systems, which can achieve complete
suppression of thermal phase oscillation. We find the real coupling of
diffusive fields can be readily established through a strong convective
background, where the decay-rate detuning is enabled by thermal metamaterial
design. Moreover, we observe phase transition of PT symmetry breaking in
diffusive systems with the symmetry-determined amplitude distribution and phase
regulation of coupled temperature fields. Our work uncovers the existence of
PT-symmetry in dissipative energy exchanges and provides a unique approach for
harnessing the mass transfer of particles, the wave propagation in strongly
scattering systems as well as thermal conduction
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