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1.
iScience ; 27(5): 109722, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38689639

RESUMO

Quantum thermodynamic process involves manipulating and controlling quantum states to extract energy or perform computational tasks with high efficiency. There is still no efficient general method to theoretically quantify the effect of the quantumness of coherence and entanglement in work extraction. In this work, we propose a thermodynamics speed to quantify the extracting work. We show that the coherence of quantum systems can speed up work extracting with respect to some cyclic evolution beyond all incoherent states. We further show the genuine entanglement of quantum systems may speed up work extracting beyond any bi-separable states. This provides a new thermodynamic method to witness entangled systems with physical quantities.

2.
Phys Rev Lett ; 131(3): 030402, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37540858

RESUMO

The quantum battery capacity is introduced in this Letter as a figure of merit that expresses the potential of a quantum system to store and supply energy. It is defined as the difference between the highest and the lowest energy that can be reached by means of the unitary evolution of the system. This function is closely connected to the ergotropy, but it does not depend on the temporary level of energy of the system. The capacity of a quantum battery can be directly linked with the entropy of the battery state, as well as with measures of coherence and entanglement.

3.
Zhongguo Gu Shang ; 36(3): 209-15, 2023 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-36946010

RESUMO

OBJECTIVE: To investigate the application of 3D printing percutaneous surgical guide plate in closed reduction and cannulated screw internal fixation of femoral neck fracture. METHODS: The clinical data of 12 patients with femoral neck fracture from March 2019 to March 2022 were retrospectively analyzed. Patients were divided into observation group and control group according to different operation plans, with 6 cases in each group. The observation group received percutaneous operation guide plate assisted closed reduction and hollow screw internal fixation, while the control group received closed reduction and hollow compression screw internal fixation. The operation time, intraoperative blood loss, fluoroscopy times, and Kirschner needle puncture times were compared between two groups. The location of screws were recordedon postoperative X-ray films, follow-up time, time of complete fracture healing, Harris score of hip joint and the incidence of complications were recorded on postoperative X-ray films. RESULTS: The operation time of observation group (32.17±6.18) min was shorter than that of control group (53.83±7.31) min (P<0.05). The amount of intraoperative bleeding in the observation group (18.33±2.94) ml was less than that in the control group (38.17±5.56) ml(P<0.05). The times of fluoroscopy in the observation group (7.50±1.05) were less than those in the control group (21.00±4.82) (P<0.05). The number of Kirschner needle punctures (8.00±0.63) in observation group was less than that in control group (32.67±3.08) (P<0.05). The follow-up time was(12.88±0.74) months in observation group and (12.83±0.72) months in control group, there was no significant difference between two groups (P>0.05). One year after operation, Harris score of hip joint in the observation group was(82.00±4.52) points, while that in the control group was(81.00±3.41) points, there was no significant difference between two groups(P>0.05). The time of complete fracture healing in the observation group was (7.50±1.05) months, while that in the control group was (7.67±1.21) months, there was no significant difference between two groups(P>0.05). The parallelism of the screws in the observation group was (0.50±0.11) ° and (0.76±0.15) °, which were lower than that in the control group (1.57±0.31) ° and (1.87±0.21) ° (P<0.05). The screw distribution area ratio (0.13±0.02) cm2 in the observation group was higher than that in the control group (0.08±0.01) cm2 (P<0.05). No complications such as necrosis of femoral head, nonunion of fracture, shortening of femoral neck and withdrawal of internal fixation occurred in both groups. CONCLUSION: The application of 3D printing percutaneous surgical guide plate improves the accuracy and safety of closed reduction and cannulated screw internal fixation for femoral neck fracture. It has the advantages of minimally invasive, reducing radiation exposure, fast and accurate, shortening the operation time and reducing intraoperative bleeding.


Assuntos
Fraturas do Colo Femoral , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas , Parafusos Ósseos , Impressão Tridimensional
4.
iScience ; 25(3): 103972, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35281726

RESUMO

Quantum entanglement has shown distinguished features beyond any classical state. Many methods have been presented to verify unknown entanglement with the complete information about the density matrices by quantum state tomography. In this work, we aim to identify unknown entanglement with only partial information of the state space. The witness consists of a generalized Greenberger-Horne-Zeilinger-like paradox expressed by Pauli observables, and a nonlinear entanglement witness expressed by density matrix elements. First, we verify unknown bipartite entanglement and study the robustness of entanglement witnesses against the white noise. Second, we generalize such verification to partially unknown multipartite entangled states, including the Greenberger-Horne-Zeilinger-type and W-type states. Third, we give a quantum-information application related to the quantum zero-knowledge proof. It further provides a useful method in blindly verifying universal quantum computation resources. These results may be interesting in entanglement theories, quantum communication, and quantum networks.

5.
Rep Prog Phys ; 85(5)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-34883470

RESUMO

Bell's theorem proves that quantum theory is inconsistent with local physical models. It has propelled research in the foundations of quantum theory and quantum information science. As a fundamental feature of quantum theory, it impacts predictions far beyond the traditional scenario of the Einstein-Podolsky-Rosen paradox. In the last decade, the investigation of nonlocality has moved beyond Bell's theorem to consider more sophisticated experiments that involve several independent sources which distribute shares of physical systems among many parties in a network. Network scenarios, and the nonlocal correlations that they give rise to, lead to phenomena that have no counterpart in traditional Bell experiments, thus presenting a formidable conceptual and practical challenge. This review discusses the main concepts, methods, results and future challenges in the emerging topic of Bell nonlocality in networks.

6.
Entropy (Basel) ; 23(2)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513817

RESUMO

The Nash equilibrium plays a crucial role in game theory. Most of results are based on classical resources. Our goal in this paper is to explore multipartite zero-sum game with quantum settings. We find that in two different settings there is no strategy for a tripartite classical game being fair. Interestingly, this is resolved by providing dynamic zero-sum quantum games using single quantum state. Moreover, the gains of some players may be changed dynamically in terms of the committed state. Both quantum games are robust against the preparation noise and measurement errors.

7.
Med Sci Monit ; 26: e920943, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32248202

RESUMO

BACKGROUND Bone morphogenetic proteins (BMPs) are widely involved in cancer development. However, a wealth of conflicting data raises the question of whether BMPs serve as oncogenes or as cancer suppressors. MATERIAL AND METHODS By integrating multi-omics data across cancers, we comprehensively analyzed the genomic and pharmacogenomic landscape of BMP genes across cancers. RESULTS Surprisingly, our data indicate that BMPs are globally downregulated in cancers. Further genetics and epigenetics analyses show that this abnormal expression is driven by copy number variations, especially heterozygous amplification. We next assessed the BMP-associated pathways and demonstrated that they suppress cell cycle and estrogen hormone pathways. Bone morphogenetic protein interacts with 58 compounds, and their dysfunction can induce drug sensitivity. CONCLUSIONS Our results define the landscape of the BMP family at a systems level and open potential therapeutic opportunities for cancer patients.


Assuntos
Proteínas Morfogenéticas Ósseas , Neoplasias/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas Morfogenéticas Ósseas/fisiologia , Variações do Número de Cópias de DNA , Humanos , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/fisiologia
8.
Phys Rev Lett ; 124(9): 092001, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32202853

RESUMO

We report a calculation of the perturbative matching coefficients for the transverse-momentum-dependent parton distribution functions for quark at the next-to-next-to-next-to-leading order in QCD, which involves calculation of nonstandard Feynman integrals with rapidity divergence. We introduce a set of generalized integration-by-parts equations, which allows an algorithmic evaluation of such integrals using the machinery of modern Feynman integral calculation.

9.
Zhongguo Gu Shang ; 31(12): 1156-1163, 2018 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-30583659

RESUMO

OBJECTIVE: Meta-analysis was used to compare the clinical efficacy of high tibial osteotomy(HTO) and unicondylar arthroplasty (UKA) in the treatment of medial compartment osteoarthritis (MIOA) and provide a better surgical choice for patients with MIOA. METHODS: The Cochrane Library (Issue 6, 2017), PubMed, Ovid, ELSIVE, CNKI and Wanfang databases were searched by a computer. Literatures on HTO and UKA for MIOA from January 1, 1970 to June 30, 2017, including complications, knee joint score, knee mobility, revision rate and excellent and good rate, were searched and screened out according to the inclusion criteria, and strict quality evaluation was carried out. RevMan 5.0 software provided by Cochrane collaboration network was used to conduct the meta-analysis of the included research results and to test the heterogeneity of the data. RESULTS: Total 13 articles met the inclusion criteria, and the total sample size was 1 043. Among them, 462 were HTO treatment group and 581 were UKA treatment group. By comparison between HTO treatment group and UKA treatment group, there were significant differences in the contralateral deterioration rate[WMD=3.21, 95%CI(1.13, 9.10)], pre-operative knee range of motion[WMD=6.55, 95%CI(1.44, 11.66)], Lysholm knee score[WMD=-3.15, 95%CI(-4.77, -1.53)], complications[WMD=2.78, 95%CI(1.52, 5.11], revision rate[WMD=1.81, 95%CI(1.17, 2.80)], the rate of excellent and good[WMD=0.49, 95%CI(0.30, 0.80)], and femorotibial angle changes[WMD=-2.37, 95%CI, (-3.63, -1.11)](P<0.05). There were no significant differences between the HTO treatment group and the UKA treatment group in patellofemoral deterioration rate[WMD=1.59, 95%CI(0.65, 3.84)] and the free walking speed[WMD=-0.02, 95%CI(-0.09, 0.04)](P>0.05). CONCLUSIONS: Based on the limited data, high tibial osteotomy is a better choice for the treatment of medial compartment osteoarthritis in the comparison of short and medium-term clinical outcomes, and long-term clinical outcomes may need further study.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Osteotomia , Humanos , Articulação do Joelho , Tíbia/cirurgia , Resultado do Tratamento
10.
Phys Rev Lett ; 120(14): 140402, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29694137

RESUMO

The correlations in quantum networks have attracted strong interest with new types of violations of the locality. The standard Bell inequalities cannot characterize the multipartite correlations that are generated by multiple sources. The main problem is that no computationally efficient method is available for constructing useful Bell inequalities for general quantum networks. In this work, we show a significant improvement by presenting new, explicit Bell-type inequalities for general networks including cyclic networks. These nonlinear inequalities are related to the matching problem of an equivalent unweighted bipartite graph that allows constructing a polynomial-time algorithm. For the quantum resources consisting of bipartite entangled pure states and generalized Greenberger-Horne-Zeilinger (GHZ) states, we prove the generic nonmultilocality of quantum networks with multiple independent observers using new Bell inequalities. The violations are maximal with respect to the presented Tsirelson's bound for Einstein-Podolsky-Rosen states and GHZ states. Moreover, these violations hold for Werner states or some general noisy states. Our results suggest that the presented Bell inequalities can be used to characterize experimental quantum networks.

11.
Sci Rep ; 8: 46957, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29553139

RESUMO

This corrects the article DOI: 10.1038/srep07627.

12.
Phys Rev Lett ; 120(10): 102001, 2018 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-29570336

RESUMO

The energy-energy correlation (EEC) between two detectors in e^{+}e^{-} annihilation was computed analytically at leading order in QCD almost 40 years ago, and numerically at next-to-leading order (NLO) starting in the 1980s. We present the first analytical result for the EEC at NLO, which is remarkably simple, and facilitates analytical study of the perturbative structure of the EEC. We provide the expansion of the EEC in the collinear and back-to-back regions through next-to-leading power, information which should aid resummation in these regions.

13.
Sci Rep ; 7: 46302, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28406240

RESUMO

Quantum cryptography is commonly used to generate fresh secure keys with quantum signal transmission for instant use between two parties. However, research shows that the relatively low key generation rate hinders its practical use where a symmetric cryptography component consumes the shared key. That is, the security of the symmetric cryptography demands frequent rate of key updates, which leads to a higher consumption of the internal one-time-pad communication bandwidth, since it requires the length of the key to be as long as that of the secret. In order to alleviate these issues, we develop a matrix algorithm for fast and simple high-capacity quantum cryptography. Our scheme can achieve secure private communication with fresh keys generated from Fibonacci- and Lucas- valued orbital angular momentum (OAM) states for the seed to construct recursive Fibonacci and Lucas matrices. Moreover, the proposed matrix algorithm for quantum cryptography can ultimately be simplified to matrix multiplication, which is implemented and optimized in modern computers. Most importantly, considerably information capacity can be improved effectively and efficiently by the recursive property of Fibonacci and Lucas matrices, thereby avoiding the restriction of physical conditions, such as the communication bandwidth.

14.
Sci Rep ; 7(1): 1234, 2017 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-28450701

RESUMO

The qudit system may offer great flexibilities for quantum information processing. We investigate the possibility of realizing elementary quantum gates between two high-dimensional atoms in distant cavities coupled by an optical fiber. We show that highly reliable special swap gate is achievable by different detuning. The numerical simulation shows that the proposed elementary gate is robust against the atomic spontaneous decay, photon leakage of cavities and optical fibers by choosing the experimental parameters appropriately.

15.
Sci Rep ; 6: 31350, 2016 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-27515908

RESUMO

With prevalent attacks in communication, sharing a secret between communicating parties is an ongoing challenge. Moreover, it is important to integrate quantum solutions with classical secret sharing schemes with low computational cost for the real world use. This paper proposes a novel hybrid threshold adaptable quantum secret sharing scheme, using an m-bonacci orbital angular momentum (OAM) pump, Lagrange interpolation polynomials, and reverse Huffman-Fibonacci-tree coding. To be exact, we employ entangled states prepared by m-bonacci sequences to detect eavesdropping. Meanwhile, we encode m-bonacci sequences in Lagrange interpolation polynomials to generate the shares of a secret with reverse Huffman-Fibonacci-tree coding. The advantages of the proposed scheme is that it can detect eavesdropping without joint quantum operations, and permits secret sharing for an arbitrary but no less than threshold-value number of classical participants with much lower bandwidth. Also, in comparison with existing quantum secret sharing schemes, it still works when there are dynamic changes, such as the unavailability of some quantum channel, the arrival of new participants and the departure of participants. Finally, we provide security analysis of the new hybrid quantum secret sharing scheme and discuss its useful features for modern applications.

16.
Sci Rep ; 6: 29939, 2016 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-27424767

RESUMO

Most of previous quantum computations only take use of one degree of freedom (DoF) of photons. An experimental system may possess various DoFs simultaneously. In this paper, with the weak cross-Kerr nonlinearity, we investigate the parallel quantum computation dependent on photonic systems with two DoFs. We construct nearly deterministic controlled-not (CNOT) gates operating on the polarization spatial DoFs of the two-photon or one-photon system. These CNOT gates show that two photonic DoFs can be encoded as independent qubits without auxiliary DoF in theory. Only the coherent states are required. Thus one half of quantum simulation resources may be saved in quantum applications if more complicated circuits are involved. Hence, one may trade off the implementation complexity and simulation resources by using different photonic systems. These CNOT gates are also used to complete various applications including the quantum teleportation and quantum superdense coding.

17.
Sci Rep ; 6: 25977, 2016 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-27174302

RESUMO

Quantum systems are important resources for quantum computer. Different from previous encoding forms using quantum systems with one degree of freedom (DoF) or two DoFs, we investigate the possibility of photon systems encoding with three DoFs consisting of the polarization DoF and two spatial DoFs. By exploring the optical circular birefringence induced by an NV center in a diamond embedded in the photonic crystal cavity, we propose several hybrid controlled-NOT (hybrid CNOT) gates operating on the two-photon or one-photon system. These hybrid CNOT gates show that three DoFs may be encoded as independent qubits without auxiliary DoFs. Our result provides a useful way to reduce quantum simulation resources by exploring complex quantum systems for quantum applications requiring large qubit systems.

18.
Sci Rep ; 5: 16716, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26568078

RESUMO

Quantum computation offers potential advantages in solving a number of interesting and difficult problems. Several controlled logic gates, the elemental building blocks of quantum computer, have been realized with various physical systems. A general technique was recently proposed that significantly reduces the realization complexity of multiple-control logic gates by harnessing multi-level information carriers. We present implementations of a key quantum circuit: the three-qubit Toffoli gate. By exploring the optical selection rules of one-sided optical microcavities, a Toffoli gate may be realized on all combinations of photon and quantum spins in the QD-cavity. The three general controlled-NOT gates are involved using an auxiliary photon with two degrees of freedom. Our results show that photons and quantum spins may be used alternatively in quantum information processing.

19.
Sci Rep ; 5: 13255, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26272869

RESUMO

Universal quantum logic gates are important elements for a quantum computer. In contrast to previous constructions of qubit systems, we investigate the possibility of ququart systems (four-dimensional states) dependent on two DOFs of photon systems. We propose some useful one-parameter four-dimensional quantum transformations for the construction of universal ququart logic gates. The interface between the spin of a photon and an electron spin confined in a quantum dot embedded in a microcavity is applied to build universal ququart logic gates on the photon system with two freedoms. Our elementary controlled-ququart gates cost no more than 8 CNOT gates in a qubit system, which is far less than the 104 CNOT gates required for a general four-qubit logic gate. The ququart logic is also used to generate useful hyperentanglements and hyperentanglement-assisted quantum error-correcting code, which may be available in modern physical technology.

20.
Sci Rep ; 5: 11169, 2015 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-26095049

RESUMO

Quantum switch is a primitive element in quantum network communication. In contrast to previous switch schemes on one degree of freedom (DOF) of quantum systems, we consider controlled switches of photon system with two DOFs. These controlled photon switches are constructed by exploring the optical selection rules derived from the quantum-dot spins in one-sided optical microcavities. Several double controlled-NOT gate on different joint systems are greatly simplified with an auxiliary DOF of the controlling photon. The photon switches show that two DOFs of photons can be independently transmitted in quantum networks. This result reduces the quantum resources for quantum network communication.

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