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Genuine Einstein-Podolsky-Rosen steering of generalized three-qubit states via unsharp measurements
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作者 陈玉玉 郭奋卓 +1 位作者 魏士慧 温巧燕 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期215-225,共11页
We aim to explore all possible scenarios of(1→2)(where one wing is untrusted and the others two wings are trusted)and(2→1)(where two wings are untrusted,and one wing is trusted)genuine tripartite Einstein-Podolsky-R... We aim to explore all possible scenarios of(1→2)(where one wing is untrusted and the others two wings are trusted)and(2→1)(where two wings are untrusted,and one wing is trusted)genuine tripartite Einstein-Podolsky-Rosen(EPR)steering.The generalized Greenberger-Horne-Zeilinger(GHZ)state is shared between three spatially separated parties,Alice,Bob and Charlie.In both(1→2)and(2→1),we discuss the untrusted party and trusted party performing a sequence of unsharp measurements,respectively.For each scenario,we deduce an upper bound on the number of sequential observers who can demonstrate genuine EPR steering through the quantum violation of tripartite steering inequality.The results show that the maximum number of observers for the generalized GHZ states can be the same with that of the maximally GHZ state in a certain range of state parameters.Moreover,both the sharpness parameters range and the state parameters range in the scenario of(1→2)steering are larger than those in the scenario of(2→1)steering. 展开更多
关键词 quantum information quantum steering generalized Greenberger-Horne-Zeilinger(GHZ)state
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Effect of atmospheric turbulence on entangled orbital angular momentum three-qubit state 被引量:5
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作者 闫香 张鹏飞 +3 位作者 张京会 冯晓星 乔春红 范承玉 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期148-151,共4页
The entangled orbital angular momentum(OAM) three photons propagating in Kolmogorov weak turbulence are investigated. Here, the single phase screen model is used to study the entanglement evolution of OAM photons. T... The entangled orbital angular momentum(OAM) three photons propagating in Kolmogorov weak turbulence are investigated. Here, the single phase screen model is used to study the entanglement evolution of OAM photons. The results indicate that the entangled OAM three-qubit state with higher OAM modes will be more robust against turbulence.Furthermore, it is found that the entangled OAM three-qubit state has a higher overall transmission for small OAM values. 展开更多
关键词 three-qubit state turbulence atmosphere Kolmogorov turbulence
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Quantum Information Splitting of an Arbitrary Three-Qubit State by Using Cluster States and Bell States 被引量:2
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作者 LI Yuan-Hua LIU Jun-Chang NIE Yi-You 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第3期421-425,共5页
A new application of cluster states is investigated for quantum information splitting (QIS) of an arbitrary three-qubit state. In our scheme, a four-qubit cluster state and a Bell state are shared by a sender (Alic... A new application of cluster states is investigated for quantum information splitting (QIS) of an arbitrary three-qubit state. In our scheme, a four-qubit cluster state and a Bell state are shared by a sender (Alice), a controller (Charlie), and a receiver (Bob). Both the sender and controller only need to perform Bell-state measurements (BSMs), the receiver can reconstruct the arbitrary three-qubit state by performing some appropriately unitary transformations on his qubits after he knows the measured results of both the sender and the controller. This QIS scheme is deterministic. 展开更多
关键词 quantum information quantum information splitting cluster states arbitrary three-qubit state Bell-state measurement
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Probabilistic Controlled Teleportation of an Arbitrary Three-Qubit State 被引量:1
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作者 ZHA Xin-Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期637-639,共3页
Recently Jiang et al.[Chin.Phys.Lett.24 (2007) 1144] gave a scheme for probabilistic controlled tele-portation of a triplet W state from the sender Alice to the distant receiver Bob.The m controlled qubits are sharedb... Recently Jiang et al.[Chin.Phys.Lett.24 (2007) 1144] gave a scheme for probabilistic controlled tele-portation of a triplet W state from the sender Alice to the distant receiver Bob.The m controlled qubits are sharedby m(s_1,s_2,...,s_m) spatially-separated supervisors.Based on transformation operator,we can extend to teleporting anarbitrary three-qubit state.The relation between the transformation operators and the Bob's unitary transformation isalso obtained. 展开更多
关键词 controlled teleportation three-qubit state transformation operator
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Deterministic remote state preparation of arbitrary three-qubit state through noisy cluster-GHZ channel
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作者 Zhihang Xu Yuzhen Wei +1 位作者 Cong Jiang Min Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期133-142,共10页
We propose a novel scheme for remote state preparation of an arbitrary three-qubit state with unit success probability,utilizing a nine-qubit cluster-GHZ state without introducing auxiliary qubits.Furthermore,we proce... We propose a novel scheme for remote state preparation of an arbitrary three-qubit state with unit success probability,utilizing a nine-qubit cluster-GHZ state without introducing auxiliary qubits.Furthermore,we proceed to investigate the effects of different quantum noises(e.g.,amplitude-damping,phase-damping,bit-flip and phase-flip noises)on the systems.The fidelity results of three-qubit target state are presented,which are usually used to illustrate how close the output state is to the target state.To compare the different effects between the four common types of quantum noises,the fidelities under one specific identical target state are also calculated and discussed.It is found that the fidelity of the phase-flip noisy channel drops the fastest through the four types of noisy channels,while the fidelity is found to always maintain at 1 in bit-flip noisy channel. 展开更多
关键词 deterministic remote state preparation arbitrary three-qubit state cluster state quantum noises
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Efficient remote preparation of arbitrary twoand three-qubit states via the χ state 被引量:2
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作者 马松雅 罗明星 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期100-106,共7页
The application of χ state are investigated in remote state preparation (RSP). By constructing useful measurement bases with the aid of Hurwitz matrix equation, we propose several RSP schemes of arbitrary two- and ... The application of χ state are investigated in remote state preparation (RSP). By constructing useful measurement bases with the aid of Hurwitz matrix equation, we propose several RSP schemes of arbitrary two- and three-qubit states via the χ state as the entangled resource. It is shown that the original state can be successfully prepared with the probability 100% and 50% for real coefficients and complex coefficients, respectively. For the latter case, the special ensembles with unit success probability are discussed by the permutation group. It is worth mentioning that the novel measurement bases have no restrictions on the coefficients of the prepared state, which means that the proposed schemes are more applicable. 展开更多
关键词 χ state remote state preparation Hurwitz matrix equation measurement basis permutation group
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Deterministic joint remote state preparation of arbitrary two-and three-qubit states 被引量:1
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作者 王媛 计新 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期92-96,共5页
We propose a novel deterministic protocol that two senders are capable of remotely preparing arbitrary two-and three-qubit states for a remote receiver using EPR pairs and GHZ state as the quantum channel.Compared wit... We propose a novel deterministic protocol that two senders are capable of remotely preparing arbitrary two-and three-qubit states for a remote receiver using EPR pairs and GHZ state as the quantum channel.Compared with the existing deterministic protocols [An et al.2011 Phys.Lett.A 375 3570 and Chen et al.2012 J.Phys.A:Math.Theor.45 055303],the quantum resources and classical information in our scheme are decreased,and the whole operation process is simplified. 展开更多
关键词 joint remote state preparation EPR pairs GHZ state
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Invariants for a Class of Nongeneric Three-Qubit States
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作者 SUN Bao-Zhi FEI Shao-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1007-1010,共4页
We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations are presented for a class of non-generic three-qubit mixed states.... We investigate the equivalence of quantum states under local unitary transformations. A complete set of invariants under local unitary transformations are presented for a class of non-generic three-qubit mixed states. It is shown that two such states in this class are locally equivalent if and only if all these invariants have equal values for them. 展开更多
关键词 INVARIANT quantum state local unitary transformation
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Number-chaotic State光场与原子相互作用耦合系统中的量子关联
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作者 格日乐 张燕 +1 位作者 呼斯楞 萨楚尔夫 《量子光学学报》 北大核心 2024年第3期82-91,共10页
在强度关联耦合(IDC)条件下,对单模Number-chaotic State光场与两个二能级原子相互作用系统中的纠缠与量子关联动力学演化特性进行了探究。着重研究了多光子跃迁和强度耦合参数对纠缠与量子关联特性的影响。结果表明,当量子纠缠为零时,... 在强度关联耦合(IDC)条件下,对单模Number-chaotic State光场与两个二能级原子相互作用系统中的纠缠与量子关联动力学演化特性进行了探究。着重研究了多光子跃迁和强度耦合参数对纠缠与量子关联特性的影响。结果表明,当量子纠缠为零时,原子间仍然存在着一定的量子关联效应。随光场光子数的增大,纠缠与量子关联演化的周期均变短,光子跃迁数增大将使得量子纠缠与量子关联的演化呈现无规振荡形式。 展开更多
关键词 量子光学 量子关联 量子纠缠 Number-chaotic state光场 多光子跃迁
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Morphology and valence state evolution of Cu:Unraveling the impact on nitric oxide electroreduction 被引量:1
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作者 Ting Sun Fengyu Gao +4 位作者 Ya Wang Honghong Yi Qingjun Yu Shunzheng Zhao Xiaolong Tang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期276-286,共11页
Ammonia(NH3)serves as a critical component in the fertilizer industry and fume gas denitrification.However,the conventional NH3production process,namely the Haber-Bosch process,leads to considerable energy consumption... Ammonia(NH3)serves as a critical component in the fertilizer industry and fume gas denitrification.However,the conventional NH3production process,namely the Haber-Bosch process,leads to considerable energy consumption and waste gas emissions.To address this,electrocatalytic nitric oxide reduction reaction(NORR)has emerged as a promising strategy to bridge NH3consumption to NH3production,harnessing renewable electricity for a sustainable future.Copper(Cu)stands out as a prominent electrocatalyst for NO reduction,given its exceptional NH3yield and selectivity.However,a crucial aspect that remains insufficiently explored is the effects of morphology and valence states of Cu on the NORR performance.In this investigation,we synthesized CuO nanowires(CuO-NF)and Cu nanocubes(Cu-NF)as cathodes through an in situ growth method.Remarkably,CuO-NF exhibited an impressive NH3yield of 0.50±0.02 mg cm^(-2)h^(-1)at-0.6 V vs.reversible hydrogen electrode(RHE)with faradaic efficiency of29,68%±1,35%,surpassing that of Cu-NF(0.17±0.01 mg cm^(-2)h^(-1),16.18%±1.40%).Throughout the electroreduction process,secondary cubes were generated on the CuO-NF surface,preserving their nanosheet cluster morphology,sustained by an abundant supply of subsurface oxygen(s-O)even after an extended duration of 10 h,until s-O depletion ensued.Conversely,Cu-NF exhibited inadequate s-O content,leading to rapid crystal collapse within the same timeframe.The distinctive current-potential relationship,akin to a volcano-type curve,was attributed to distinct NO hydrogenation mechanisms.Further Tafel analysis revealed the exchange current density(i0)and standard heterogeneous rate constant(k0)for CuO-NF,yielding 3.44×10^(-6)A cm^(-2)and 3.77×10^(-6)cm^(-2)s^(-1)when NORR was driven by overpotentials.These findings revealed the potential of CuO-NF for NO reduction and provided insights into the intricate interplay between crystal morphology,valence states,and electrochemical performance. 展开更多
关键词 NORR Ammonia Synthesis COPPER MORPHOLOGY Valence states Mechanism
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Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases 被引量:1
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作者 Yating ZHAO Ming XUE +2 位作者 Jing JIANG Xiao-Ming HU Anning HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期619-638,共20页
Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss pos... Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are available.The RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of precipitation.This dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the simulation.Inaccuracy in reproducing large-scale circulation and environmental conditions is another contributing factor.The too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great Plains.The simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as well.Therefore,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios. 展开更多
关键词 NARCCAP Central United states PRECIPITATION low-level jet large-scale environment diurnal variation
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Thermal safety boundary of lithium-ion battery at different state of charge 被引量:1
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作者 Hang Wu Siqi Chen +8 位作者 Yan Hong Chengshan Xu Yuejiu Zheng Changyong Jin Kaixin Chen Yafei He Xuning Feng Xuezhe Wei Haifeng Dai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期59-72,共14页
Thermal runaway(TR)is a critical issue hindering the large-scale application of lithium-ion batteries(LIBs).Understanding the thermal safety behavior of LIBs at the cell and module level under different state of charg... Thermal runaway(TR)is a critical issue hindering the large-scale application of lithium-ion batteries(LIBs).Understanding the thermal safety behavior of LIBs at the cell and module level under different state of charges(SOCs)has significant implications for reinforcing the thermal safety design of the lithium-ion battery module.This study first investigates the thermal safety boundary(TSB)correspondence at the cells and modules level under the guidance of a newly proposed concept,safe electric quantity boundary(SEQB).A reasonable thermal runaway propagation(TRP)judgment indicator,peak heat transfer power(PHTP),is proposed to predict whether TRP occurs.Moreover,a validated 3D model is used to quantitatively clarify the TSB at different SOCs from the perspective of PHTP,TR trigger temperature,SOC,and the full cycle life.Besides,three different TRP transfer modes are discovered.The interconversion relationship of three different TRP modes is investigated from the perspective of PHTP.This paper explores the TSB of LIBs under different SOCs at both cell and module levels for the first time,which has great significance in guiding the thermal safety design of battery systems. 展开更多
关键词 Lithium-ion battery Battery safety Thermal runaway state of charge Numerical analysis
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Pixelated non-volatile programmable photonic integrated circuits with 20-level intermediate states 被引量:1
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作者 Wenyu Chen Shiyuan Liu Jinlong Zhu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期477-487,共11页
Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum information.In this ... Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum information.In this paper,we propose pixelated programmable Si_(3)N_(4)PICs with record-high 20-level intermediate states at 785 nm wavelength.Such flexibility in phase or amplitude modulation is achieved by a programmable Sb_(2)S_(3)matrix,the footprint of whose elements can be as small as 1.2μm,limited only by the optical diffraction limit of anin-house developed pulsed laser writing system.We believe our work lays the foundation for laser-writing ultra-high-level(20 levels and even more)programmable photonic systems and metasurfaces based on phase change materials,which could catalyze diverse applications such as programmable neuromorphic photonics,biosensing,optical computing,photonic quantum computing,and reconfigurable metasurfaces. 展开更多
关键词 programmable photonic integrated circuits phase change materials multi-level intermediate states metasurfaces
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Semi-analytical solution for drained expansion analysis of a hollow cylinder of critical state soils 被引量:1
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作者 He Yang Jialiang Zhang +1 位作者 Haisui Yu Peizhi Zhuang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2326-2340,共15页
The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by ... The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material points.As a result,this problem cannot be solved by the common self-similar-based similarity techniques.This paper proposes a novel,exact solution for rigorous drained expansion analysis of a hollow cylinder of critical state soils.Considering stress-dependent elastic moduli of soils,new analytical stress and displacement solutions for the nonself-similar problem are developed taking the small strain assumption in the elastic zone.In the plastic zone,the cavity expansion response is formulated into a set of first-order partial differential equations(PDEs)with the combination use of Eulerian and Lagrangian descriptions,and a novel solution algorithm is developed to efficiently solve this complex boundary value problem.The solution is presented in a general form and thus can be useful for a wide range of soils.With the new solution,the non-self-similar nature induced by the finite outer boundary is clearly demonstrated and highlighted,which is found to be greatly different to the behaviour of cavity expansion in infinite soil mass.The present solution may serve as a benchmark for verifying the performance of advanced numerical techniques with critical state soil models and be used to capture the finite boundary effect for pressuremeter tests in small-sized calibration chambers. 展开更多
关键词 Cavity expansion Drained analysis Boundary effect Critical state soil Non-self-similar Eulerian-Lagrangian approach
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Three-qubit海森堡XYZ各向异性自旋链系统QMA熵不确定度的量子调控
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作者 刘科洋 周清平 《原子与分子物理学报》 北大核心 2024年第6期109-116,共8页
本文研究了three-qubit海森堡XYZ各向异性自旋链系统各项参数和外加磁场对量子存储支撑(Quantum memory assisted,QMA)熵不确定度及其下限的调控行为,以及对被测系统与存储系统之间量子纠缠的影响.结果表明:增大系统的Dzyaloshinski-Mor... 本文研究了three-qubit海森堡XYZ各向异性自旋链系统各项参数和外加磁场对量子存储支撑(Quantum memory assisted,QMA)熵不确定度及其下限的调控行为,以及对被测系统与存储系统之间量子纠缠的影响.结果表明:增大系统的Dzyaloshinski-Moriya(DM)相互作用强度、降低系统温度、增大沿Z正方向磁场强度可以提高被测系统与存储系统之间的量子纠缠,降低系统QMA熵不确定度及其下限,被测系统与存储系统之间的量子纠缠与QMA熵不确定度及其下限呈类反相关. 展开更多
关键词 three-qubit海森堡XYZ各向异性自旋链 QMA熵不确定度 DM相互作用 平方负性纠缠
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Association of DNA methylation/demethylation with the functional outcome of stroke in a hyperinflammatory state 被引量:1
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作者 Yubo Wang Ling Zhang +6 位作者 Tianjie Lyu Lu Cui Shunying Zhao Xuechun Wang Meng Wang Yongjun Wang Zixiao Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2229-2239,共11页
Inflammation is closely related to stroke prognosis, and high inflammation status leads to poor functional outcome in stroke. DNA methylation is involved in the pathogenesis and prognosis of stroke. However, the effec... Inflammation is closely related to stroke prognosis, and high inflammation status leads to poor functional outcome in stroke. DNA methylation is involved in the pathogenesis and prognosis of stroke. However, the effect of DNA methylation on stroke at high levels of inflammation is unclear. In this study, we constructed a hyperinflammatory cerebral ischemia mouse model and investigated the effect of hypomethylation and hypermethylation on the functional outcome. We constructed a mouse model of transient middle cerebral artery occlusion and treated the mice with lipopolysaccharide to induce a hyperinflammatory state. To investigate the effect of DNA methylation on stroke, we used small molecule inhibitors to restrain the function of key DNA methylation and demethylation enzymes. 2,3,5-Triphenyltetrazolium chloride staining, neurological function scores, neurobehavioral tests, enzyme-linked immunosorbent assay, quantitative reverse transcription PCR and western blot assay were used to evaluate the effects after stroke in mice. We assessed changes in the global methylation status by measuring DNA 5-mc and DNA 5-hmc levels in peripheral blood after the use of the inhibitor. In the group treated with the DNA methylation inhibitor, brain tissue 2,3,5-triphenyltetrazolium chloride staining showed an increase in infarct volume, which was accompanied by a decrease in neurological scores and worsening of neurobehavioral performance. The levels of inflammatory factors interleukin 6 and interleukin-1 beta in ischemic brain tissue and plasma were elevated, indicating increased inflammation. Related inflammatory pathway exploration showed significant overactivation of nuclear factor kappa B. These results suggested that inhibiting DNA methylation led to poor functional outcome in mice with high inflammation following stroke. Further, the effects were reversed by inhibition of DNA demethylation. Our findings suggest that DNA methylation regulates the inflammatory response in stroke and has an important role in the functional outcome of hyperinflammatory stroke. 展开更多
关键词 DNA demethylation DNA methylation DNMT3A functional outcome hyperinflammatory state INTERLEUKIN NEUROINFLAMMATION STROKE TET2
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Whole-process case management effects on mental state and selfcare ability in patients with liver cancer 被引量:1
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作者 Man-Di Ju Qin Qin Meng Li 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期833-841,共9页
BACKGROUND Regarding the incidence of malignant tumors in China,the incidence of liver cancer ranks fourth,second only to lung,gastric,and esophageal cancers.The case fatality rate ranks third after lung and cervical ... BACKGROUND Regarding the incidence of malignant tumors in China,the incidence of liver cancer ranks fourth,second only to lung,gastric,and esophageal cancers.The case fatality rate ranks third after lung and cervical cancer.In a previous study,the whole-process management model was applied to patients with breast cancer,which effectively reduced their negative emotions and improved treatment adherence and nursing satisfaction.METHODS In this single-center,randomized,controlled study,60 randomly selected patients with liver cancer who had been admitted to our hospital from January 2021 to January 2022 were randomly divided into an observation group(n=30),who received whole-process case management on the basis of routine nursing mea-sures,and a control group(n=30),who were given routine nursing measures.We compared differences between the two groups in terms of anxiety,depression,the level of hope,self-care ability,symptom distress,sleep quality,and quality of life.RESULTS Post-intervention,Hamilton anxiety scale,Hamilton depression scale,memory symptom assessment scale,and Pittsburgh sleep quality index scores in both groups were lower than those pre-intervention,and the observation group had lower scores than the control group(P<0.05).Herth hope index,self-care ability assessment scale-revision in Chinese,and quality of life measurement scale for patients with liver cancer scores in both groups were higher than those pre-intervention,with higher scores in the observation group compared with the control group(P<0.05).CONCLUSION Whole-process case management can effectively reduce anxiety and depression in patients with liver cancer,alleviate symptoms and problems,and improve the level of hope,self-care ability,sleep quality,and quality of life,as well as provide feasible nursing alternatives for patients with liver cancer. 展开更多
关键词 Liver cancer Mental state Self-care ability Whole-process case management Life quality NURSING
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Machine-learning-assisted efficient reconstruction of the quantum states generated from the Sagnac polarization-entangled photon source
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作者 毛梦辉 周唯 +3 位作者 李新慧 杨然 龚彦晓 祝世宁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期50-54,共5页
Neural networks are becoming ubiquitous in various areas of physics as a successful machine learning(ML)technique for addressing different tasks.Based on ML technique,we propose and experimentally demonstrate an effic... Neural networks are becoming ubiquitous in various areas of physics as a successful machine learning(ML)technique for addressing different tasks.Based on ML technique,we propose and experimentally demonstrate an efficient method for state reconstruction of the widely used Sagnac polarization-entangled photon source.By properly modeling the target states,a multi-output fully connected neural network is well trained using only six of the sixteen measurement bases in standard tomography technique,and hence our method reduces the resource consumption without loss of accuracy.We demonstrate the ability of the neural network to predict state parameters with a high precision by using both simulated and experimental data.Explicitly,the mean absolute error for all the parameters is below 0.05 for the simulated data and a mean fidelity of 0.99 is achieved for experimentally generated states.Our method could be generalized to estimate other kinds of states,as well as other quantum information tasks. 展开更多
关键词 machine learning state estimation quantum state tomography polarization-entangled photon source
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Target layer state estimation in multi-layer complex dynamical networks considering nonlinear node dynamics
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作者 吴亚勇 王欣伟 蒋国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期245-252,共8页
In many engineering networks, only a part of target state variables are required to be estimated.On the other hand,multi-layer complex network exists widely in practical situations.In this paper, the state estimation ... In many engineering networks, only a part of target state variables are required to be estimated.On the other hand,multi-layer complex network exists widely in practical situations.In this paper, the state estimation of target state variables in multi-layer complex dynamical networks with nonlinear node dynamics is studied.A suitable functional state observer is constructed with the limited measurement.The parameters of the designed functional observer are obtained from the algebraic method and the stability of the functional observer is proven by the Lyapunov theorem.Some necessary conditions that need to be satisfied for the design of the functional state observer are obtained.Different from previous studies, in the multi-layer complex dynamical network with nonlinear node dynamics, the proposed method can estimate the state of target variables on some layers directly instead of estimating all the individual states.Thus, it can greatly reduce the placement of observers and computational cost.Numerical simulations with the three-layer complex dynamical network composed of three-dimensional nonlinear dynamical nodes are developed to verify the effectiveness of the method. 展开更多
关键词 multi-layer complex dynamical network nonlinear node dynamics target state estimation functional state observer
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Topological edge and corner states of valley photonic crystals with zipper-like boundary conditions
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作者 沈云峰 许孝芳 +2 位作者 孙铭 周文佶 常雅箐 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期480-491,共12页
We present a stable valley photonic crystal(VPC)unit cell with C_(3v)symmetric quasi-ring-shaped dielectric columns and realize its topological phase transition by breaking mirror symmetry.Based on this unit cell stru... We present a stable valley photonic crystal(VPC)unit cell with C_(3v)symmetric quasi-ring-shaped dielectric columns and realize its topological phase transition by breaking mirror symmetry.Based on this unit cell structure,topological edge states(TESs)and topological corner states(TCSs)are realized.We obtain a new type of wave transmission mode based on photonic crystal zipper-like boundaries and apply it to a beam splitter assembled from rectangular photonic crystals(PCs).The constructed beam splitter structure is compact and possesses frequency separation functions.In addition,we construct a box-shaped triangular PC structures with zipper-like boundaries and discover phenomena of TCSs in the corners,comparing its corner states with those formed by other boundaries.Based on this,we explore the regularities of the electric field patterns of TESs and TCSs,explain the connection between the characteristic frequencies and locality of TCSs,which helps better control photons and ensures low power consumption of the system. 展开更多
关键词 valley photonic crystal topological edge states topological corner states higher-order topological insulators topological phase transition
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