734 research outputs found
Determination of impact parameter in high-energy heavy-ion collisions via deep learning
In this study, Au+Au collisions with the impact parameter of fm at GeV are simulated by the AMPT model to
provide the preliminary final-state information. After transforming these
information into appropriate input data (the energy spectra of final-state
charged hadrons), we construct a deep neural network (DNN) and a convolutional
neural network (CNN) to connect final-state observables with impact parameters.
The results show that both the DNN and CNN can reconstruct the impact
parameters with a mean absolute error about fm with CNN behaving slightly
better. Then, we test the neural networks for different beam energies and
pseudorapidity ranges in this task. It turns out that these two models work
well for both low and high energies. But when making test for a larger
pseudorapidity window, we observe that the CNN shows higher prediction accuracy
than the DNN. With the method of Grad-CAM, we shed light on the `attention'
mechanism of the CNN model
6-Formyl-2-naphthyl cis-1,5,7-trimethyl-2,4-dioxo-3-azabicyclo[3.3.1]nonane-7-carboxylate
In the title compound, C23H23NO5, the C5N ring adopts an envelope conformation with a C atom as the flap, whilst the saturated C6 ring fused to it adopts a chair conformation. In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds generate R
2
2(8) loops
Detecting Chiral Magnetic Effect via Deep Learning
The search of chiral magnetic effect (CME) in heavy-ion collisions has
attracted long-term attentions. Multiple observables have been proposed but all
suffer from obstacles due to large background contaminations. In this Letter,
we construct an observable-independent CME-meter based on a deep convolutional
neural network. After trained over data set generated by a multiphase transport
model, the CME-meter shows high accuracy in recognizing the CME-featured charge
separation from the final-state pion spectra. It also exhibits remarkable
robustness to diverse conditions including different collision energies,
centralities, and elliptic flow backgrounds. In a transfer learning manner, the
CME-meter is validated in isobaric collision systems, showing good
transferability among different colliding systems. Based on variational
approaches, we utilize the DeepDream method to derive the most responsive
CME-spectra that demonstrates the physical contents the machine learns.Comment: 7 pages, 10 figure
Epimedium brevicornu Maxim extract shows protective activity against Alzheimer's disease in mice
Purpose: To investigate the protective effect of Epimedium brevicornu Maxim extract (EBME) against Alzheimer's disease in 3xTg-AD mice.
Methods: The cognitive function of 3xTg-AD mice was assessed using Morris water maze test. The levels of amyloid beta deposits and NeuN in the mouse hippocampus were evaluated by immunohistochemistry. Brain neurotrophic-derived factor (BDNF) and tyrosine kinase B (TrkB) expressions were examined by western blot analysis.
Results: EBME treatment significantly ameliorated learning and memory deficits in AD mice, as shown by the increased time spent in the target zone during probe tests. Compared with the 3xTg-AD mice (8.4 ± 1.1 s), the escape latency in animals treated with 600 mg/kg EBME (21.5 ± 1.1 s) was significantly increased (p < 0.01). In addition, EBME significantly decreased Aβ deposits, increased NeuN-positive cells, and upregulated the expressions of BDNF (1.5 ± 0.2, p < 0.05) and TrkB (1.6 ± 0.2, p < 0.05) in the 3xTg AD mice.
Conclusion: EBME treatment may be a useful therapeutic strategy for managing memory impairment
Experimental investigation of the non-Markovian dynamics of classical and quantum correlations
We experimentally investigate the dynamics of classical and quantum
correlations of a Bell diagonal state in a non-Markovian dephasing environment.
The sudden transition from classical to quantum decoherence regime is observed
during the dynamics of such kind of Bell diagonal state. Due to the refocusing
effect of the overall relative phase, the quantum correlation revives from near
zero and then decays again in the subsequent evolution. However, the
non-Markovian effect is too weak to revive the classical correlation, which
remains constant in the same evolution range. With the implementation of an
optical operation, the sudden transition from quantum to classical
revival regime is obtained and correlation echoes are formed. Our method can be
used to control the revival time of correlations, which would be important in
quantum memory.Comment: extended revision, accepted for publication in Physical Review
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