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One of the main challenges in developing high-performance quantum batteries is the self-discharging process, where energy is dissipated from a quantum battery into the environment. In this work, we investigate the influence of non-Markovian noises on the performance of a quantum battery. Our results demonstrate that adding auxiliary qubits to a quantum battery system can effectively suppress the self-discharging process, leading to an improvement in both the steady-state energy and extractable work. We reveal that the physical mechanism inhibiting the self-discharging process is the formation of system-environment bound states, rather than an increase in non-Markovianity. Our results could be of both theoretical and experimental interest in exploring the ability of quantum batteries to maintain long stored energy in the environment.
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The competition between on-site electronic correlation and local crystal field stands out as a captivating topic in research. However, its physical ramifications often get overshadowed by influences of strong periodic potential and orbital hybridization. The present study reveals this competition may become more pronounced or even dominant in two-dimensional systems, driven by the combined effects of dimensional confinement and orbital anisotropy. This leads to electronic orbital reconstruction in certain perovskite superlattices or thin films. To explore the emerging physics, we investigate the interfacial orbital disorder-order transition with an effective Hamiltonian and how to modulate this transition through strains.
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BACKGROUND: Liver injury is common in severe acute pancreatitis (SAP). Excessive autophagy often leads to an imbalance of homeostasis in hepatocytes, which induces lipid peroxidation and mitochondrial iron deposition and ultimately leads to ferroptosis. Our previous study found that milk fat globule epidermal growth factor 8 (MFG-E8) alleviates acinar cell damage during SAP via binding to αvß3/5 integrins. MFG-E8 also seems to mitigate pancreatic fibrosis via inhibiting chaperone-mediated autophagy. AIM: To speculate whether MFG-E8 could also alleviate SAP induced liver injury by restoring the abnormal autophagy flux. METHODS: SAP was induced in mice by 2 hly intraperitoneal injections of 4.0 g/kg L-arginine or 7 hly injections of 50 µg/kg cerulein plus lipopolysaccharide. mfge8-knockout mice were used to study the effect of MFG-E8 deficiency on SAP-induced liver injury. Cilengitide, a specific αvß3/5 integrin inhibitor, was used to investigate the possible mechanism of MFG-E8. RESULTS: The results showed that MFG-E8 deficiency aggravated SAP-induced liver injury in mice, enhanced autophagy flux in hepatocyte, and worsened the degree of ferroptosis. Exogenous MFG-E8 reduced SAP-induced liver injury in a dose-dependent manner. Mechanistically, MFG-E8 mitigated excessive autophagy and inhibited ferroptosis in liver cells. Cilengitide abolished MFG-E8's beneficial effects in SAP-induced liver injury. CONCLUSION: MFG-E8 acts as an endogenous protective mediator in SAP-induced liver injury. MFG-E8 alleviates the excessive autophagy and inhibits ferroptosis in hepatocytes by binding to integrin αVß3/5.
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Doença Hepática Crônica Induzida por Substâncias e Drogas , Ferroptose , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Pancreatite , Camundongos , Animais , Fator VIII , Pancreatite/induzido quimicamente , Pancreatite/complicações , Doença Aguda , Hepatócitos/metabolismo , Autofagia , Família de Proteínas EGF , Proteínas do Leite/metabolismo , Proteínas do Leite/farmacologiaRESUMO
We propose a mechanism to simultaneously enhance quantum cooling and entanglement via coupling an auxiliary microwave cavity to a magnomechanical cavity. The auxiliary cavity acts as a dissipative cold reservoir that can efficiently cool multiple localized modes in the primary system via beam-splitter interactions, which enables us to obtain strong quantum cooling and entanglement. We analyze the stability of the system and determine the optimal parameter regime for cooling and entanglement under the auxiliary-microwave-cavity-assisted (AMCA) scheme. The maximum cooling enhancement rate of the magnon mode can reach 98.53%, which clearly reveals that the magnomechanical cooling is significantly improved in the presence of the AMCA. More importantly, the dual-mode entanglement of the system can also be significantly enhanced by AMCA in the full parameter region, where the initial magnon-phonon entanglement can be maximally enhanced by a factor of about 11. Another important result of the AMCA is that it also increases the robustness of the entanglement against temperature. Our approach provides a promising platform for the experimental realization of entanglement and quantum information processing based on cavity magnomechanics.
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Anisotropic plasmonic metasurfaces have attracted broad research interest since they possess novel optical properties superior to natural materials and their tremendous design flexibility. However, the realization of multi-wavelength selective plasmonic metasurfaces that have emerged as promising candidates to uncover multichannel optical devices remains a challenge associated with weak modulation depths and narrow operation bandwidth. Herein, we propose and numerically demonstrate near-infrared multi-wavelength selective passive plasmonic switching (PPS) that encompasses high ON/OFF ratios and strong modulation depths via multiple Fano resonances (FRs) in anisotropic plasmonic metasurfaces. Specifically, the double FRs can be fulfilled and dedicated to establishing tailorable near-infrared dual-wavelength PPS. The multiple FRs mediated by in-plane mirror asymmetries cause the emergence of triple-wavelength PPS, whereas the multiple FRs governed by in-plane rotational asymmetries avail the implementation of the quasi-bound states in the continuum-endowed multi-wavelength PPS with the ability to unfold a tunable broad bandwidth. In addition, the strong polarization effects with in-plane anisotropic properties further validate the existence of the polarization-resolved multi-wavelength PPS. Our results provide an alternative approach to foster the achievement of multifunctional meta-devices in optical communication and information processing.
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Rydberg excitons, the solid-state counterparts of Rydberg atoms, have sparked considerable interest with regard to the harnessing of their quantum application potentials, but realizing their spatial confinement and manipulation poses a major challenge. Lately, the rise of two-dimensional moiré superlattices with highly tunable periodic potentials provides a possible pathway. Here, we experimentally demonstrate this capability through the spectroscopic evidence of Rydberg moiré excitons (XRM), which are moiré-trapped Rydberg excitons in monolayer semiconductor tungsten diselenide adjacent to twisted bilayer graphene. In the strong coupling regime, the XRM manifest as multiple energy splittings, pronounced red shift, and narrowed linewidth in the reflectance spectra, highlighting their charge-transfer character wherein electron-hole separation is enforced by strongly asymmetric interlayer Coulomb interactions. Our findings establish the excitonic Rydberg states as candidates for exploitation in quantum technologies.
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Floquet engineering plays a key role in realizing novel dynamical topological states. The conventional Floquet engineering, however, only applies to time-periodic non-dissipative Hermitian systems, and for the open quantum systems, non-Hermitian processes usually occur. So far, it remains unclear how to characterize the topological phases of time-periodic open quantum systems via the frequency space Floquet Hamiltonian. Here, we propose the non-Floquet theory to solve the problem and illustrate it by a continuously time-periodic non-Hermitian bipartite chain. In non-Floquet theory, a temporal non-unitary transformation is exercised on the Floquet states, and the transformed Floquet spectrum restores the form of the Wannier-Stark ladder. Besides, we also show that different choices of the starting points of the driving period can result in different localization behavior, effects of which can reversely be utilized to design quantum detectors of phases in dissipative oscillating fields. Our methods are capable of describing topological features in dynamical open quantum systems with various driving types and can find its applications to construct new types of dynamical topological materials.
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We study a non-Hermitian chiral topological superconductor system on two dimensional square lattice, from which we obtained a rich topological phase diagram and established an exact relationship between topological charge flow of exceptional points in generalized Brillouin zone and change of topological properties. Its rich topological phase diagram is the result of competition between anisotropy and non-Hermitian effect. This system belongs to class D according to AZ classification of non-Hermitian systems. Each topological phase can be characterized by a 2DZnumber, which indicates the number of chiral edge modes, and two 1DZ2numbers, which indicate the existence of zero modes at edge dislocations.
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The superfluid properties of attractive Hubbard model in dice lattice are investigated. It is found that three superfluid order parameters increase as the interaction increases. When the filling factor falls into the flat band, due to the infinite large density of states, the resultant superfluid order parameters are proportional to interaction strength, which is in striking contrast with the exponentially small counterparts in usual superfluid (or superconductor). When the interaction is weak, and the filling factor is near the bottom of the lowest band (or the top of highest band), the superfluid density is determined by the effective mass of the lowest (or highest) single-particle band. When the interaction is strong and filling factor is small, the superfluid density is inversely proportional to interaction strength, which is related to effective mass of tightly bound pairs. In the strong interaction limit and finite filling, the asymptotic behaviors of superfluid density can be captured by a parabolic function of filling factor. Furthermore, when the filling is in flat band, the superfluid density shows a logarithmic singularity as the interaction approaches zero. In addition, there exist three undamped collective modes for strong interactions. The lowest excitation is gapless phonon, which is characterized by the total density oscillations. The two others are gapped Leggett modes, which correspond relative density fluctuations between sublattices. The collective modes are also reflected in the two-particle spectral functions by sharp peaks. Furthermore, it is found that the two-particle spectral functions satisfy an exact sum-rule, which is directly related to the filling factor (or density of particle). The sum-rule of the spectral functions may be useful to distinguish between the hole-doped and particle-doped superfluid (superconductor) in experiments.
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We investigate the first-order metal-ferromagnetic insulator phase transition on the puckered honeycomb lattice, combining the cellular dynamical mean field theory with the continuous-time quantum Monte Carlo method. By analyzing the interplay among intrinsic spin-orbit coupling (SOC), Rashba SOC and on-site interaction, we show that the ferromagnetic (FM) order and the antiferromagnetic (AFM) order occur in different regimes. Rashba SOC allows the electron spin flipping, which leads to the phase transition from the metal to FM insulator induced by the increasing on-site interaction. In contrast to the usual continuous metal-antiferromagnetic insulator phase transition, we find that the metal-ferromagnetic insulator transition is first-order by computing the double occupancy. Furthermore, the complete phase diagrams of the Rashba SOC, on-site interaction and temperature are also demonstrated.
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BACKGROUND: Whether to use a T-tube for biliary anastomosis during orthotopic liver transplantation (OLT) remains a debatable question. Some surgeons chose to use a T-tube because they believed that it reduces the incidence of biliary strictures. Advances in surgical techniques during the last decades have significantly decreased the overall incidence of postoperative biliary complications. Whether using a T-tube during OLT is still associated with the reduced incidence of biliary strictures needs to be re-evaluated. AIM: To provide an updated systematic review and meta-analysis on using a T-tube during adult OLT. METHODS: In the electronic databases MEDLINE, PubMed, Scopus, ClinicalTrials.gov, the Cochrane Library, the Cochrane Hepato-Biliary Group Controlled Trails Register, and the Cochrane Central Register of Controlled Trials, we identified 17 studies (eight randomized controlled trials and nine comparative studies) from January 1995 to October 2020. The data of the studies before and after 2010 were separately extracted. We chose the overall biliary complications, bile leaks or fistulas, biliary strictures (anastomotic or non-anastomotic), and cholangitis as outcomes. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to describe the results of the outcomes. Furthermore, the test for overall effect (Z) was used to test the difference between OR and 1, where P ≤ 0.05 indicated a significant difference between OR value and 1. RESULTS: A total of 1053 subjects before 2010 and 1346 subjects after 2010 were included in this meta-analysis. The pooled results showed that using a T-tube reduced the incidence of postoperative biliary strictures in studies before 2010 (P = 0.012, OR = 0.62, 95%CI: 0.42-0.90), while the same benefit was not seen in studies after 2010 (P = 0.60, OR = 0.76, 95%CI: 0.27-2.12). No significant difference in the incidence of overall biliary complications (P = 0.37, OR = 1.41, 95%CI: 0.66-2.98), bile leaks (P = 0.89, OR = 1.04, 95%CI: 0.63-1.70), and cholangitis (P = 0.27, OR = 2.00, 95%CI: 0.59-6.84) was observed between using and not using a T-tube before 2010. However, using a T-tube appeared to increase the incidence of overall biliary complications (P = 0.049, OR = 1.49, 95%CI: 1.00-2.22), bile leaks (P = 0.048, OR = 1.91, 95%CI: 1.01-3.64), and cholangitis (P = 0.02, OR = 7.21, 95%CI: 1.37-38.00) after 2010. A random-effects model was used in biliary strictures (after 2010), overall biliary complications (before 2010), and cholangitis (before 2010) due to their heterogeneity (I 2 = 62.3%, 85.4%, and 53.6%, respectively). In the sensitivity analysis (only RCTs included), bile leak (P = 0.66) lost the significance after 2010 and a random-effects model was used in overall biliary complications (before 2010), cholangitis (before 2010), bile leaks (after 2010), and biliary strictures (after 2010) because of their heterogeneity (I 2 = 92.2%, 65.6%, 50.9%, and 80.3%, respectively). CONCLUSION: In conclusion, the evidence gathered in our updated meta-analysis showed that the studies published in the last decade did not provide enough evidence to support the routine use of T-tube in adults during OLT.
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Procedimentos Cirúrgicos do Sistema Biliar , Sistema Biliar , Transplante de Fígado , Procedimentos de Cirurgia Plástica , Adulto , Anastomose Cirúrgica , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Humanos , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgiaRESUMO
The extensive proliferation of recent coronavirus (COVID-19), all over the world, is the outcome of social interactions through massive transportation, gatherings and population growth. To disrupt the widespread of COVID-19, a mechanism for social distancing is indispensable. Also, to predict the effectiveness and quantity of social distancing for a particular social network, with a certain contagion, a generalized model is needed. In this manuscript, we propose a social distancing mediated generalized model to predict the pandemic spread of COVID-19. By considering growth rate as a temporal harmonic function damped with social distancing in generalized Richard model and by using the data of confirmed COVID-19 cases in China, USA and India, we find that, with time, the cumulative spread grows more rapidly due to weak social distancing as compared to the stronger social distancing, where it is explicitly decreasing. Furthermore, we predict the possible outcomes with various social distancing scenarios by considering highest growth rate as an initial state, and illustrate that the increase in social distancing tremendously decreases growth rate, even it tends to reach zero in lockdown regimes. Our findings not only provide epidemic growth scenarios as a function of social distancing but also provide a modified growth model to predict controlled information flow in any network.
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We investigate ergodic time scales in single-particle tracking by introducing a covariance measure Ω(Δ;t) for the time-averaged relative square displacement recorded in lag-time Δ at elapsed time t. The present model is established in the generalized Langevin equation with a power-law memory function. The ratio Ω(Δ;Δ)/Ω(Δ;t) is shown to obey a universal scaling law for long but finite times and is used to extract the effective ergodic time. We derive a finite-time-averaged Green-Kubo relation and find that, to control the deviations in measurement results from ensemble averages, the ratio Δ/t must be neither too small nor close to unity. Our paper connects the experimental self-averaging property of a tracer with the theoretic velocity autocorrelation function and sheds light on the transition to ergodicity.
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We investigate the charging process of open quantum battery in the weak system-environment coupling regime. A method to improve the performance of open quantum battery in a reservoir environment, which described by a band-gap environment model or a two-Lorentzian environment model, is proposed by manipulating the spectral density of environment. We find that the optimal quantum battery, characterized by fast charging time and large ergotropy, in the band-gap environment can be obtained by increasing the weights of two Lorentzians and the spectral width of the second Lorentzian, which is in sharp contrast to the quantum battery in two-Lorentzian environment. Then we extend our discussion to multiple coupled reservoir environments, which are composed of N coupled dissipative cavities. We show that, the performance of quantum battery can be enhanced by increasing the coupling strength between the nearest-neighbor environments and decreasing the size of the environments. In particular, to fully charge and extract the total stored energy as work for quantum battery can be achieved by manipulating the coupling strength between the nearest-neighbor environments. Our results provide a practical approach for the realization of the optimal quantum batteries in future experiments.
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We demonstrate the existence of finite-component multicriticality in a qubit-boson model where biased qubits collectively coupled to a single-mode bosonic field. The interplay between biases and boson-qubit coupling produces a rich phase diagram which shows multiple superradiant phases and phase boundaries of different orders. In particular, multiple phases become indistinguishable in appropriate bias configurations, which is the signature of multicriticality. A series of universality classes characterizing these multicritical points are identified. Moreover, we present a trapped-ion realization with the potential to explore multicritical phenomena experimentally using a small number of ions. The results open a novel way to probe multicritical universality classes in experiments.
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Floquet Majorana edge modes capture the topological features of periodically driven p-wave superconductors. We present a Kitaev chain with multiple time periodic driving terms. Our results demonstrate how multiple driving will affect Floquet bands in frequency space, leading to more robust Floquet Majorana edge modes against driving frequency ω in comparison with the single driving scenario. Meanwhile, we have proposed how to predict Majorana edge modes via the Zak phase of Floquet bands. Besides, in contrast to the cases with single driving term, where the constant phase can be gauged out by properly choosing the initial time, we have shown the relative phase between multiple driving can not be gauged out and will play a dominant role in deciding topological phase transitions. For the sake of completeness, we also investigate the high frequency limit. Analytical results on effective Hamiltonian can be obtained via Magnus expansion and relative phase induced topological transitions can be shown explicitly.
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We investigate the topological supersolid states of dipolar Fermi gases trapped in a spin-dependent 2D optical lattice. Our results show that topological supersolid states can be achieved via the combination of topological superfluid states with the stripe order. Different from the general held belief that supersolid state in fermionic system can only survive with simultaneous coexistence of the repulsive and attractive dipolar interaction. We demonstrate that it can be maintained when the dipolar interaction is attractive in both x and y direction. By adjusting the ratio of hopping amplitude between different directions and dipolar interaction strength U, the system will undergo a phase transition among p x + ip y superfluid state, p y -wave superfluid state, and the topological supersolid state. The supersolid state in the attractive environment is proved to be stable by the positive sign of the inverse compressibility. We also design an experimental protocol to realize the staggered next-next-nearest-neighbor hopping via the laser assisted tunneling technique, which is the key to simulate the spin-dependent potential.
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We provide a unified and exact framework for the variance-based uncertainty relations. This unified framework not only recovers some well-known previous uncertainty relations, but also fixes the deficiencies of them. Utilizing the unified framework, we can construct the new uncertainty relations in both product and sum form for two and more incompatible observables with any tightness we require. Moreover, one can even construct uncertainty equalities to exactly express the uncertainty relation by the unified framework, and the framework is therefore exact in describing the uncertainty relation. Some applications have been provided to illustrate the importance of this unified and exact framework. Also, we show that the contradiction between uncertainty relation and non-Hermitian operator, i.e., most of uncertainty relations will be violated when applied to non-Hermitian operators, can be fixed by this unified and exact framework.
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BACKGROUND: Acute pancreatitis (AP) is often associated with intestinal injury, which in turn exaggerates the progression of AP. Our recent study has shown that a low level of serum irisin, a novel exercise-induced hormone, is associated with poor outcomes in patients with AP and irisin administration protects against experimental AP. However, the role of irisin in intestinal injury in AP has not been evaluated. AIM: To investigate the effect of irisin administration on intestinal injury in experimental AP. METHODS: AP was induced in male adult mice by two hourly intraperitoneal injections of L-arginine. At 2 h after the last injection of L-arginine, irisin (50 or 250 µg/kg body weight) or 1 mL normal saline (vehicle) was administered through intraperitoneal injection. The animals were sacrificed at 72 h after the induction of AP. Intestinal injury, apoptosis, oxidative and endoplasmic reticulum (ER) stress were evaluated. RESULTS: Administration of irisin significantly mitigated intestinal damage, reduced apoptosis, and attenuated oxidative and ER stress in AP mice. In addition, irisin treatment also effectively downregulated serum tumor necrosis factor-alpha and interleukin-6 levels and alleviated injury in the pancreas, liver and lung of AP mice. CONCLUSION: Irisin-mediated multiple physiological events attenuate intestinal injury following an episode of AP. Irisin has a great potential to be further developed as an effective treatment for patients with AP.
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Estresse do Retículo Endoplasmático , Fibronectinas/farmacologia , Estresse Oxidativo , Pancreatite/tratamento farmacológico , Animais , Apoptose , Arginina , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Interleucina-6/metabolismo , Intestinos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pâncreas/metabolismo , Pancreatite/induzido quimicamente , Fator de Necrose Tumoral alfa/metabolismoRESUMO
We propose a new scheme for creating three-dimensional Skyrmions in a ferromagnetic spin-1 Bose-Einstein condensate by manipulating a multipole magnetic field and a pair of counter-propagating laser beams. The result shows that a three-dimensional Skyrmion with topological number Q = 2 can be created by a sextupole magnetic field and the laser beams. Meanwhile, the vortex ring and knot structure in the Skyrmion are found. The topological number can be calculated analytically in our model, which implies that the method can be extended to create Skyrmions with arbitrary topological number. As the examples, three-dimensional Skyrmions with Q = 3, 4 are also demonstrated and are distinguishable by the density distributions with a specific quantization axis. These topological objects have the potential to be realized in ferromagnetic spin-1 Bose-Einstein condensates experimentally.