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1.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4230-4237, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467737

RESUMO

This study aimed to explore the mechanism of Xiaoyao San(XYS) in the treatment of three diseases of liver depression and spleen deficiency, ie, depression, breast hyperplasia, and functional dyspepsia, and to provide a theoretical basis for the interpretation of the scientific connotation of "treating different diseases with the same method" of traditional Chinese medicines. Traditional Chinese medicine systems pharmacology database and analysis platform(TCMSP) was used to screen the active components of XYS which underwent principal component analysis(PCA) with the available drugs for these three diseases to determine the corresponding biological activities. The targets of XYS on depression, breast hyperplasia, and functional dyspepsia were obtained from GeneCards, TTD, CTD, and DrugBank databases. Cytoscape was used to plot the "individual herbal medicine-active components-potential targets" network. The resulting key targets were subjected to Kyoto encyclopedia of genes and genomes(KEGG) pathway analysis and gene ontology(GO) enrichment analysis. A total of 121 active components of XYS and 38 common targets in the treatment of depression, breast hyperplasia, and functional dyspepsia were collected. The key biological pathways were identified, including advanced glycation and products(AGEs)-receptor for advanced glycation and products(RAGE) signaling pathway in diabetic complications, HIF-1 signaling pathway, and cancer-related pathways. The key targets of XYS in the treatment of depression, breast hyperplasia, and functional dyspepsia included IL6, IL4, and TNF, and the key components were kaempferol, quercetin, aloe-emodin, etc. As revealed by the molecular docking, a strong affinity was observed between the key components and the key targets, which confirmed the results. The therapeutic efficacy of XYS in the treatment of diseases of liver depression and spleen deficiency was presumedly achieved by reducing the inflammatory reactions. The current findings are expected to provide novel research ideas and approaches to classify the scientific connotation of "treating different diseases with the same method" of Chinese medicines, as well as a theoretical basis for understanding the mechanism of XYS and exploring its clinical applications.


Assuntos
Medicamentos de Ervas Chinesas , Dispepsia , Depressão/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Dispepsia/tratamento farmacológico , Humanos , Hiperplasia/tratamento farmacológico , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular
2.
Sci Rep ; 10(1): 20426, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33235215

RESUMO

We solve the quasi-bound state-energy spectra and wavefunctions of an NPN-type graphene quantum dot under a perpendicular magnetic field. The evolution of the quasi-bound state spectra under the magnetic field is investigated using a Wentzel-Kramers-Brillouin approximation. In numerical calculations, we also show that the twofold energy degeneracy of the opposite angular momenta breaks under a weak magnetic field. As the magnetic field strengthens, this phenomenon produces an observable splitting of the energy spectrum. Our results demonstrate the relation between the quasi-bound state-energy spectrum in graphene quantum dots and magnetic field strength, which is relevant to recent measurements in scanning tunneling microscopy.

3.
Opt Express ; 26(6): 7034-7042, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29609389

RESUMO

We propose a scheme to measure the quantum state of photons in a cavity. The proposal is based on the concept of quantum weak values and applies equally well to both the solid-state circuit and atomic cavity quantum electrodynamics (QED) systems. The proposed scheme allows us to access directly the superposition components in Fock state basis, rather than the Wigner function as usual in phase space. Moreover, the separate access feature held in the direct scheme does not require a global reconstruction for the quantum state, which provides a particular advantage beyond the conventional method of quantum state tomography.

4.
Sci Rep ; 8(1): 531, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29323255

RESUMO

In this work we present a large-deviation analysis for the counting statistics of atomic spontaneous emissions continuously detected in finite-bandwidth non-Markovian environment. We show that the statistics of the spontaneous emissions depends on the time interval (τ) of successive detections, which can result in big differences such as dynamical phase transition. This feature excludes the idea of regarding the spontaneous emissions as detection-free objective events. Possible experiment is briefly discussed in connection with the state-of-the-art optical cavity set-up.

5.
Sci Rep ; 7(1): 2576, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28566725

RESUMO

Within the framework of Boltzmann equation, we present a k · p theory based study for the low-field mobilities of InSb nanowires (InSb NWs) with relatively large cross sectional sizes (with diameters up to 51.8 nm). For such type of large size nanowires, the intersubband electron-phonon scattering is of crucial importance to affect the scattering rate and then the mobility. In our simulation, the lowest 15 electron subbands and 50 transverse modes of phonons are carefully accounted for. We find that, up to the 51.84 nm diameter, the mobility monotonously increases with the diameter, not yet showing any saturated behavior. We also find that, while the bulk InSb mobility is considerably higher than the bulk Si, the small size (e.g. ~3 nm diameter) nanowires from both materials have similar magnitude of mobilities. This implies, importantly, that the mobility of the InSb NWs would decrease faster than the SiNWs as we reduce the cross sectional size of the nanowires.

6.
J Phys Condens Matter ; 29(19): 195301, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28287397

RESUMO

The Josephson supercurrent through a hybrid Majorana-quantum dot-Majorana junction is investigated. We particularly analyze the effect of spin-selective coupling between the Majorana and quantum dot states, which only emerges in the topological phase and will influence the current through bent junctions and/or in the presence of magnetic fields in the quantum dot. We find that the characteristic behavior of the supercurrent through this system is quite counterintuitive, differing remarkably from the resonant tunneling, e.g. through the similar (normal phase) superconductor-quantum dot-superconductor junction. Our analysis is carried out under the influence of the full set-up parameters and for both the [Formula: see text] and [Formula: see text] periodic currents. The present study is expected to be relevant to the future exploration of applications of Majorana-nanowire circuits.

7.
Sci Rep ; 6: 20286, 2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26838670

RESUMO

In this work we revisit the important and controversial concept of quantum weak values, aiming to provide a simplified understanding to its associated physics and the origin of anomaly. Taking the Stern-Gerlach setup as a working system, we base our analysis on an exact treatment in terms of quantum Bayesian approach. We also make particular connection with a very recent work, where the anomaly of the weak values was claimed from the pure statistics in association with "disturbance" and "post-selection", rather than the unique quantum nature. Our analysis resolves the related controversies through a clear and quantitative way.

8.
Sci Rep ; 6: 20492, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26841968

RESUMO

Developing efficient framework for quantum measurements is of essential importance to quantum science and technology. In this work, for the important superconducting circuit-QED setup, we present a rigorous and analytic solution for the effective quantum trajectory equation (QTE) after polaron transformation and converted to the form of Stratonovich calculus. We find that the solution is a generalization of the elegant quantum Bayesian approach developed in arXiv:1111.4016 by Korotokov and currently applied to circuit-QED measurements. The new result improves both the diagonal and off-diagonal elements of the qubit density matrix, via amending the distribution probabilities of the output currents and several important phase factors. Compared to numerical integration of the QTE, the resultant quantum Bayesian rule promises higher efficiency to update the measured state, and allows more efficient and analytical studies for some interesting problems such as quantum weak values, past quantum state, and quantum state smoothing. The method of this work opens also a new way to obtain quantum Bayesian formulas for other systems and in more complicated cases.

9.
J Chem Phys ; 143(19): 194107, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26590527

RESUMO

In this work, the recently introduced quantum trajectory mean-field (QTMF) approach is implemented and employed to explore photodissociation dynamics of diazirinone (N2CO), which are based on the high-level ab initio calculation. For comparison, the photodissociation process has been simulated as well with the fewest-switches surface hopping (FSSH) and the ab initio multiple spawning (AIMS) methods. Overall, the dynamical behavior predicted by the three methods is consistent. The N2CO photodissociation at λ > 335 nm is an ultrafast process and the two C-N bonds are broken in a stepwise way, giving birth to CO and N2 as the final products in the ground state. Meanwhile, some noticeable differences were found in the QTMF, FSSH, and AIMS simulated time constants for fission of the C-N bonds, excited-state lifetime, and nonadiabatic transition ratios in different intersection regions. These have been discussed in detail. The present study provides a clear evidence that direct ab initio QTMF approach is one of the reliable tools for simulating nonadiabatic dynamics processes.

10.
Sci Rep ; 4: 7527, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25516433

RESUMO

We revisit the spin-injected field effect transistor (spin-FET) in a framework of the lattice model by applying the recursive lattice Green's function approach. In the one-dimensional case the results of simulations in coherent regime reveal noticeable differences from the celebrated Datta-Das model, which lead us to an improved treatment with generalized result. The simulations also allow us to address inelastic scattering and lateral confinement effects in the control of spins. These issues are very important in the spin-FET device.

11.
J Chem Phys ; 140(24): 244111, 2014 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-24985622

RESUMO

Beyond the second-order Born approximation, we propose an improved master equation approach to quantum transport under self-consistent Born approximation. The basic idea is to replace the free Green's function in the tunneling self-energy diagram by an effective reduced propagator under the Born approximation. This simple modification has remarkable consequences. It not only recovers the exact results for quantum transport through noninteracting systems under arbitrary voltages, but also predicts the challenging nonequilibrium Kondo effect. Compared to the nonequilibrium Green's function technique that formulates the calculation of specific correlation functions, the master equation approach contains richer dynamical information to allow more efficient studies for such as the shot noise and full counting statistics.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(1 Pt 1): 011144, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21867149

RESUMO

We investigate the dynamic quantum tunneling between two attractors of a mesoscopic driven Duffing oscillator. We find that, in addition to inducing a remarkable quantum shift of the bifurcation point, the mesoscopic nature also results in a perfect linear scaling behavior for the tunneling rate with the driving distance to the shifted bifurcation point.


Assuntos
Oscilometria/métodos , Algoritmos , Análise de Fourier , Modelos Estatísticos , Nanotecnologia/métodos , Teoria Quântica , Fatores de Tempo
13.
J Phys Condens Matter ; 21(38): 385801, 2009 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-21832377

RESUMO

Quantum measurement will inevitably cause backaction on the measured system, resulting in the well-known dephasing and relaxation. In this paper, in the context of solid-state qubit measurement by a mesoscopic detector, we show that an alternative backaction known as renormalization is important under some circumstances. This effect is largely overlooked in the theory of quantum measurement.

14.
J Chem Phys ; 126(13): 134113, 2007 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-17430022

RESUMO

A hierarchical equations of motion formalism for a quantum dissipation system in a grand canonical bath ensemble surrounding is constructed on the basis of the calculus-on-path-integral algorithm, together with the parametrization of arbitrary non-Markovian bath that satisfies fluctuation-dissipation theorem. The influence functionals for both the fermion or boson bath interaction are found to be of the same path integral expression as the canonical bath, assuming they all satisfy the Gaussian statistics. However, the equation of motion formalism is different due to the fluctuation-dissipation theories that are distinct and used explicitly. The implications of the present work to quantum transport through molecular wires and electron transfer in complex molecular systems are discussed.

15.
Phys Rev Lett ; 94(6): 066803, 2005 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-15783765

RESUMO

In this work we first derive a generalized conditional master equation for quantum measurement by a mesoscopic detector, then study the readout characteristics of qubit measurement where a number of remarkable new features are found. The work would, in particular, highlight the qubit spontaneous relaxation effect induced by the measurement itself rather than an external thermal bath.

16.
J Chem Phys ; 122(4): 41103, 2005 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-15740228

RESUMO

An exact quantum master equation formalism is constructed for the efficient evaluation of quantum non-Markovian dissipation beyond the weak system-bath interaction regime in the presence of time-dependent external field. A novel truncation scheme is further proposed and compared with other approaches to close the resulting hierarchically coupled equations of motion. The interplay between system-bath interaction strength, non-Markovian property, and required level of hierarchy is also demonstrated with the aid of simple spin-boson systems.

17.
J Agric Food Chem ; 50(10): 2926-30, 2002 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-11982421

RESUMO

Raspberries are rich in phenolic phytochemicals. To study the health benefits of raspberries, four fresh raspberry varieties (Heritage, Kiwigold, Goldie, and Anne) were evaluated for total antioxidant and antiproliferative activities. The total amount of phenolics and flavonoids for each of the four raspberry varieties was determined. The Heritage raspberry variety had the highest total phenolic content (512.7 +/- 4.7 mg/100 g of raspberry) of the varieties measured followed by Kiwigold (451.1 +/- 4.5 mg/100 g of raspberry), Goldie (427.5 +/- 7.5 mg/100 g of raspberry), and Anne (359.2 +/- 3.4 mg/100 g of raspberry). Similarly, the Heritage raspberry variety contained the highest total flavonoids (103.4 +/- 2.0 mg/100 g of raspberry) of the varieties tested, followed by Kiwigold (87.3 +/- 1.8 mg/100 g of raspberry), Goldie (84.2 +/- 1.8 mg/100 g of raspberry), and Anne (63.5 +/- 0.7 mg/100 g of raspberry). The color of the raspberry juice correlated well to the total phenolic, flavonoid, and anthocyanin contents of the raspberry. Heritage had the highest a/b ratio and the darkest colored juice, and the Anne variety showed the lowest phytochemical content and the palest color. Heritage raspberry variety had the highest total antioxidant activity, followed by Kiwigold and Goldie, and the Anne raspberry variety had the lowest antioxidant activity of the varieties tested. The proliferation of HepG(2) human liver cancer cells was significantly inhibited in a dose-dependent manner after exposure to the raspberry extracts. The extract equivalent to 50 mg of Goldie, Heritage, and Kiwigold fruit inhibited the proliferation of those cells by 89.4 +/- 0.1, 88 +/- 0.2, and 87.6 +/- 1.0%, respectively. Anne had the lowest antiproliferative activity of the varieties measured but still exhibited a significant inhibition of 70.3+/- 1.2% with an extract equivalent to 50 mg of fruit. The antioxidant activity of the raspberry was directly related to the total amount of phenolics and flavonoids found in the raspberry (p < 0.01). No relationship was found between antiproliferative activity and the total amount of phenolics/flavonoids found in the same raspberry (p > 0.05).


Assuntos
Antioxidantes/análise , Flavonoides/análise , Frutas/química , Fenóis/análise , Antocianinas/análise , Divisão Celular/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/patologia , Pigmentação , Extratos Vegetais/farmacologia , Especificidade da Espécie , Células Tumorais Cultivadas
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