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Acalypha wilkesiana L - A potential anti-stearoyl-CoA desaturase agent: Insilico and network pharmacology studies

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Intelligent Pharmacy

Intelligent Pharmacy 2024年第4期2卷 540-553页

作者： Oyebamiji, Abel Kolawole Akintelu, Sunday Adewale Ebenezer, Oluwakemi Semire, Banjo Babalola, Jonathan Oyebamiji Industrial Chemistry Programme Bowen University Osun State Iwo Nigeria School of Chemistry and Chemical Engineering Beijing Institute of Technology Beijing 100811 China Department of Physics University of Alberta Edmonton T6G 2E1 AB Canada Computational Chemistry Research Laboratory Department of Pure and Applied Chemistry Ladoke Akintola University of Technology P.M.B. 4000 Oyo State Ogbomoso Nigeria Department of Chemistry University of Ibadan Oyo State Ibadan Nigeria

The activity of Seborrheic dermatitis on the skin of children still remains of the dermatoses of male and female babies in the early days of their existence. Acalypha wilkesiana L have been employed by mothers to combat Seborrheic dermatitis, yet, the descriptors responsible for such activity as well as the nonbonding interactions between the selected phytochemicals and stearoyl-CoA desaturase has not been explored. The studied compounds were optimized using Spartan'14 software as well as molecular operating environments (MOE) for docking, Cytoscape software for compound-protein interaction network, Gromacs for molecular dynamic simulation as well ADMETSar for pharmacokinetics studies. The selected compounds proved to have anti-stearoyl-CoA desaturase properties via the calculated descriptors obtained from the chemical compounds obtained from Acalypha wilkesiana L as well as from the result from molecular modeling studies. The Pharmacokinetics results were observed and reported appropriately. © 2023 The Authors

关键词： Acalypha wilkesiana DFT Insilico Seborrheic dermatitis

Tunneling Valley Hall Effect Driven by Tilted Dirac Fermions

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Physical Review Letters 2023年第24期131卷 246301-246301页

作者： Shu-Hui Zhang Ding-Fu Shao Zi-An Wang Jin Yang Wen Yang Evgeny Y. Tsymbal College of Mathematics and Physics Beijing University of Chemical Technology Beijing 100029 China Key Laboratory of Materials Physics Institute of Solid State Physics HFIPS Chinese Academy of Sciences Hefei 230031 China University of Science and Technology of China Hefei 230026 China Beijing Computational Science Research Center Beijing 100193 China Department of Physics and Astronomy & Nebraska Center for Materials and Nanoscience University of Nebraska Lincoln Nebraska 68588-0299 USA

Valleytronics is a research field utilizing a valley degree of freedom of electrons for information processing and storage. A strong valley polarization is critical for realistic valleytronic applications. Here, we predict a tunneling valley Hall effect (TVHE) driven by tilted Dirac fermions in all-in-one tunnel junctions based on a two-dimensional (2D) valley material. Different doping of the electrode and spacer regions in these tunnel junctions results in momentum filtering of the tunneling Dirac fermions, generating a strong transverse valley Hall current dependent on the Dirac-cone tilting. Using the parameters of an existing 2D valley material, we demonstrate that such a strong TVHE can host a giant valley Hall angle even in the absence of the Berry curvature. Finally, we predict that resonant tunneling can occur in a tunnel junction with properly engineered device parameters such as the spacer width and transport direction, providing significant enhancement of the valley Hall angle. Our work opens a new approach to generate valley polarization in realistic valleytronic systems.

关键词： Dirac fermions Valley degrees of freedom 2-dimensional systems Junctions

Heisenberg and Heisenberg-like representations via Hilbert-space-bundle geometry in the non-Hermitian regime

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Physical Review A 2025年第5期111卷 052213-052213页

作者： Chia-Yi Ju Adam Miranowicz Jacob Barnett Guang-Yin Chen Franco Nori Department of Physics National Sun Yat-sen University Kaohsiung 80424 Taiwan Center for Theoretical and Computational Physics National Sun Yat-sen University Kaohsiung 80424 Taiwan Physics Division National Center for Theoretical Sciences Taipei 106319 Taiwan Institute of Spintronics and Quantum Information Faculty of Physics and Astronomy Adam Mickiewicz University 61-614 Poznań Poland Center for Quantum Computing RIKEN Wakoshi Saitama 351-0198 Japan Basque Center for Applied Mathematics Alameda de Mazarredo 14 48009 Bilbao Bizkaia Spain Department of Physics National Chung Hsing University Taichung 40227 Taiwan Department of Physics University of Michigan Ann Arbor Michigan 48109-1040 USA

The equivalence between the Schrödinger and Heisenberg representations is a cornerstone of quantum mechanics. However, this relationship remains unclear in the non-Hermitian regime, particularly when the Hamiltonian is time dependent. In this paper, we address this gap by establishing the connection between the two representations, incorporating the metric of the Hilbert space bundle. We not only demonstrate the consistency between the Schrödinger and Heisenberg representations but also present a Heisenberg-like representation grounded in the generalized vielbein formalism, which provides a clear and intuitive geometric interpretation. Unlike the standard Heisenberg representation, where the metric of the Hilbert space is encoded solely in the dual states, the Heisenberg-like representation distributes the metric information between both the states and the dual states. Despite this distinction, it retains the same Heisenberg equation of motion for operators. Within this formalism, the Hamiltonian is replaced by a Hermitian counterpart, while the “non-Hermiticity” is transferred to the operators. Moreover, this approach extends to regimes with a dynamical metric (beyond the pseudo-Hermitian framework) and to systems governed by time-dependent Hamiltonians.

关键词： Hilbert spaces

Machine-learning interatomic potential for molecular dynamics simulation of ferroelectric KNbO3 perovskite

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arXiv 2022年

作者： Thong, Hao-Cheng Wang, XiaoYang Wang, Han Zhang, Linfeng Wang, Ke Xu, Ben State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing100084 China Graduate School China Academy of Engineering Physics Beijing100193 China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Huayuan Road 6 Beijing100088 China Beijing Institute of Big Data Research Beijing100871 China

Ferroelectric perovskites have been ubiquitously applied in piezoelectric devices for decades, among which, eco-friendly lead-free (K,Na)NbO3-based materials have been recently demonstrated to be an excellent candidate for sustainable development. Molecular dynamics is a versatile theoretical calculation approach for the investigation of the dynamical properties of ferroelectric perovskites. However, molecular dynamics simulation of ferroelectric perovskites has been limited to simple systems, since the conventional construction of interatomic potential is rather difficult and inefficient. In the present study, we construct a machine-learning interatomic potential of KNbO3 (as a representative system of (K,Na)NbO3) by using a deep neural network model. Including first-principles calculation data into the training dataset ensures the quantum-mechanics accuracy of the interatomic potential. The molecular dynamics based on machine-learning interatomic potential shows good agreement with the first-principles calculations, which can accurately predict multiple fundamental properties, e.g., atomic force, energy, elastic properties, and phonon dispersion. In addition, the interatomic potential exhibits satisfactory performance in the simulation of domain wall and temperature-dependent phase transition. The construction of interatomic potential based on machine learning could potentially be transferred to other ferroelectric perovskites and consequently benefits the theoretical study of ferroelectrics. © 2022, CC BY.

关键词： Molecular dynamics

Phase-dependent cross sections of deuteron-triton fusion in dichromatic intense fields with high-frequency limit

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arXiv 2021年

作者： Lv, Wenjuan Duan, Hao Liu, Jie Graduate School China Academy of Engineering Physics Beijing100193 China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing100088 China Institute of Applied Physics and Computational Mathematics Beijing100088 China CAPT HEDPS IFSA Collaborative Innovation Center of MoE Peking University Beijing100871 China

We investigate the influence of strong dichromatic laser fields(i.e. 1ω-2ω and 1ω-3ω) with high-frequency limit on the cross sections of deuteron-triton(DT) fusion in Kramers-Henneberger(KH) frame. We focus on the transitions of phase-dependent effects depending on a dimensionless quantity nd, which equals the ratio of the quiver oscillation amplitude to the geometrical touching radius of the deuteron and triton as defined in our previous research. Theoretical calculations show that the angle-dependent as well as phase-dependent Coulomb barrier penetrabilities can be enhanced in dichromatic intense fields, and the corresponding angle-averaged penetrabilities and the fusion cross sections increase significantly compared with field-free case. Moreover, we find that there are twice shifts of the peak in the cross sections whenever the frequency becomes sufficiently low or the intensity sufficiently high. The reason for the first shift is the angle-dependence effects for sub-barrier fusion, while the second shift is due to the accumulation of over-barrier fusion, these mechanisms are analyzed in detail in this paper. Copyright © 2021, The Authors. All rights reserved.

关键词： Deuterium

Kinetic modelling and reactivity of liquid nitromethane under detonation conditions

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Communications chemistry 2025年第1期8卷 188页

作者： Teng Zhang Lang Chen Kun Yang Bin Zhang Tuo Yang Yao Long Jianying Lu Danyang Liu Jun Chen Beijing Institute of Technology Beijing China. Beijing Institute of Technology Beijing China. chenlang@***. Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing China. Beijing Institute of Technology Beijing China. liudy@***. Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing China. jun_chen@***. HEDPS Center for Applied Physics and Technology and College of Engineering Peking University Beijing China. jun_chen@***.

Liquid nitromethane (NM) may undergo detonation under accidental stimuli, making kinetic modeling crucial for assessing the safety risks associated with its detonation. This study employs first-principles molecular dynamics to investigate chemical behavior of nitromethane under high temperature (>2000 K) and pressure (>1 GPa) conditions, revealing five previously unidentified intermediates (CHNOH, CHNOH, CHNOH, CHONO, NOCHNO) and establishing a nitromethane chemical kinetic model which include 543 elementary reactions and 79 species, which is successfully applied in the prediction of nitromethane detonation characteristics. The calculated detonation pressure (13.5 GPa) and reaction zone time (46 ns) are in agreement with the experimental values (11.5-12.0 GPa; 50-53 ns). We also uncover the delayed response mechanism in pure nitromethane detonation. The major pollutants, many CO (34.8%), and small amount of NH (1.7%), HCN (1.0%), etc. in nitromethane detonation products are found. These findings advance the fundamental understanding of nitromethane's detonation reaction kinetics.

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Study on coupling of smooth particle method with finite elements based on mesh-particle matching degree

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International Journal of Safety and Security Engineering 2019年第3期9卷 261-268页

作者： Liu, Jun Wang, Pei He, Anmin Institute of Applied Physics and Computational Mathematics Beijing China

In this paper, a new algorithm coupling the finite element and smooth particle methods is proposed. It is an improved algorithm based on the hybrid coupling method. By calculating the mesh-particle matching degree, the new method can better deal with a poor mesh-particle matching relationship. The coupling algorithm can also ensure the transmission of tension and shear stress and the natural disconnection of the contact surface. The comparison of impact simulation shows that the algorithm can deal with mesh-particle separation and re-compaction better, and the coupling interface force is smooth and non-oscillatory. Finally, the new coupling algorithm is applied to the detonation driving problem, and the calculated results are in good agreement with the experimental results. © 2019 WIT Press

关键词： Shear stress

An Efficient Quantum Circuit for Block Encoding a Pairing Hamiltonian

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arXiv 2024年

作者： Liu, Diyi Du, Weijie Lin, Lin Vary, James P. Yang, Chao Department of Mathematics University of Minnesota Twin CitiesMN United States Department of Physics Iowa State University of Minnesota AmesIA United States Department of Mathematics University of California BerkeleyCA United States Applied Mathematics and Computational Research Division Lawrence Berkeley National Laboratory BerkeleyCA United States

We present an efficient quantum circuit for block encoding pairing Hamiltonians often studied in nuclear physics. Our block encoding scheme does not require mapping the creation and annihilation operators to the Pauli operators and representing the Hamiltonian as a linear combination of unitaries. Instead, we show how to encode the Hamiltonian directly using controlled swap operations. We analyze the gate complexity of the block encoding circuit and show that it scales polynomially with respect to the number of qubits required to represent a quantum state associated with the pairing Hamiltonian. We also show how the block encoding circuit can be combined with the quantum singular value transformation to construct an efficient quantum circuit for approximating the density of states of a pairing Hamiltonian. The techniques presented can be extended to encode more general second-quantized *** Codes 68Q12, 81P68 © 2024, CC BY.

关键词： Hamiltonians

Test of electric charge conservation in dark matter direct detection experiment

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arXiv 2025年

作者： Zhang, Z.H. Geng, X.P. Hu, J.W. Zhang, Z.H. Beijing Normal University at Zhuhai Zhuhai519087 China Institute of Applied Physics and Computational Mathematics Beijing100094 China Beijing Honest Technology Co. Ltd Beijing100083 China China Nuclear Power Technology Research Institute Co. Ltd Shenzhen518000 China

Electric charge conservation (ECC) is typically taken as an axiom in the standard model. Searching for small violations with high-performance experiments could lead us to new physics. In this work, we tested "invisible" electric charge nonconservation (ECNC) events with 1.16 ton·year electron recoil data from the XENON-nT experiment. There was no statistically significant signal, and the ECNC limit was updated to τ(e− → νe + ν¯e + νe) > 4.34 × 1027 yr. This work increases the limit by two orders of magnitude and shows that dark matter direct detection experiments have great potential for further ECC testing. Copyright © 2025, The Authors. All rights reserved.

关键词： Dark Matter