9,335 research outputs found
Steady Bell state generation via magnon-photon coupling
We show that parity-time () symmetry can be spontaneously
broken in the recently reported energy level attraction of magnons and cavity
photons. In the -broken phase, magnon and photon form a
high-fidelity Bell state with maximum entanglement. This entanglement is steady
and robust against the perturbation of environment, in contrast to the general
wisdom that expects instability of the hybridized state when the symmetry is
broken. This anomaly is further understood by the compete of non-Hermitian
evolution and particle number conservation of the hybridized system. As a
comparison, neither -symmetry broken nor steady magnon-photon
entanglement is observed inside the normal level repulsion case. Our results
may open a novel window to utilize magnon-photon entanglement as a resource for
quantum technologies.Comment: 5 pages, 4 figure
Heavy- and light-flavor symmetry partners of the , the and the from light-meson exchange saturation
The spectrum of the charmed meson-(anti)meson system is a fundamental tool
for disentangling the nature of a few exotic hadrons, including the recently
discovered tetraquark, the , or the , the
nature of which is still not clear after almost two decades of its discovery.
Here we consider that the charmed meson-(anti)meson short-range interaction is
described by the exchange of light-mesons (, , ). The
effects of light-meson exchanges are recast into a simple contact-range theory
by means of a saturation procedure, resulting in a compact description of the
two-hadron interaction. From this, if the were to be an isoscalar
molecule, then there should exist an isoscalar partner,
as constrained by heavy-quark spin symmetry. Yet, within our model, the most
attractive two charmed meson configurations are the isovector
molecule and its sextet and flavor partners. Finally,
we find a tension between the molecular descriptions of the and that
of the and , where most parameter choices suggest that if
the is purely molecular then the overbinds (or conversely,
if the is a molecule the does not bind). This might be
consequential for determining the nature of these states.Comment: 13 pages, 4 table
肾上腺素在膝关节镜手术中的应用
Objective: To explore the preparation method of epinephrine for knee arthroscopy, and to find the best temperature and concentration. Methods: A total of 60 cases of knee arthroscopy in our department, from September 2011 to January 2013, was divided into 6 groups. Condition for group A: low temperature (8℃), and low concentration (3000ml saline+0.5ml epinephrine); Group B:low temperature, but high concentration (3000ml saline+1ml epinephrine); Group C: normal temperature (23℃), and low concentration; Group D: normal temperature (23℃), and high concentration; Group E: heating (37℃),but low concentration; Group F: heating (37℃),and high concentration. Each group was used for the operation, and the effect of hemostasis and the changes of vital signs of the patients were observed during the operation. Results: The bleeding amounts in Group C and Group E were more than other groups, and the red blood cell counts increased significantly in the flushing fluid of the two groups. The effect of hemostasis in Group A, B, D and F was good. The patients in Group A, B, C, and D experienced a rapid rise or fall in temperature due to massive application of douching fluid. The patients in Group F didn’t experience much interference. Conclusion: The application of heating epinephrine imposes less interference to the patients’ vital signs during knee arthroscopy. Moreover, the effect of hemostasis is good, and the safety of the operation improved. It is worth to be popularized.目的 探讨膝关节镜手术中肾上腺素关节灌注液的配制方法,寻找最佳配制温度及浓度。方法 将我科2011年9月—2013年1月进行的60例膝关节镜手术随机分为6组:A组为低温(8℃)、低浓度组(3000ml生理盐水+0.5ml肾上腺素),B组为低温高浓度组(3000ml生理盐水+1ml肾上腺素),C组为常温(23℃)低浓度组,D组为常温高浓度组,E组为加温(37℃)低浓度组,F组为加温高浓度组,术中将各组分别于手术中灌注,观察患者术中的止血效果及患者生命体征的变化。结果 C组及E组患者术中出血较多,冲洗液中红细胞计数较其他组明显增加;A组、B组、D组、F组患者术中止血效果良好,术野清晰,但A组、B组、C组、D组患者因大量灌洗液的应用,患者体温均产生了不同程度的波动;F组对患者的生命体征干扰较少,效果良好。结论 膝关节镜手术中应用加温后的肾上腺素关节灌洗液对患者的生命体征干扰较少,术中止血效果好,提高了手术的安全性,值得推广
Interactive Speech and Noise Modeling for Speech Enhancement
Speech enhancement is challenging because of the diversity of background
noise types. Most of the existing methods are focused on modelling the speech
rather than the noise. In this paper, we propose a novel idea to model speech
and noise simultaneously in a two-branch convolutional neural network, namely
SN-Net. In SN-Net, the two branches predict speech and noise, respectively.
Instead of information fusion only at the final output layer, interaction
modules are introduced at several intermediate feature domains between the two
branches to benefit each other. Such an interaction can leverage features
learned from one branch to counteract the undesired part and restore the
missing component of the other and thus enhance their discrimination
capabilities. We also design a feature extraction module, namely
residual-convolution-and-attention (RA), to capture the correlations along
temporal and frequency dimensions for both the speech and the noises.
Evaluations on public datasets show that the interaction module plays a key
role in simultaneous modeling and the SN-Net outperforms the state-of-the-art
by a large margin on various evaluation metrics. The proposed SN-Net also shows
superior performance for speaker separation.Comment: AAAI 2021 (Accepted
Impacts of changed litter inputs on soil CO2 efflux in three forest types in central south China
The pentaquark and its partners in the molecular picture
The LHCb collaboration has detected a new hidden-charm pentaquark with the
quantum numbers of a baryon: the . In the
molecular picture this pentaquark will be interpreted as a
molecule. Here we briefly comment on the relation of the new with the . We find that the
and both accept a
common molecular description in terms of the same parameters, which predicts
the existence of a few additional , ,
and pentaquarks composed of a
charmed antimeson and an antitriplet charmed baryon. The most robust of these
predicted pentaquarks is a with a mass in the
range, while other two interesting ones are a
and a , the later basically at
the same mass as the , with which it might mix owing
to isospin symmetry breaking effects.Comment: 5 pages, 1 tabl
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