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1.
World J Clin Cases ; 9(30): 8999-9010, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34786383

RESUMO

BACKGROUND: Stroke has a great influence on the patient's mental health, and reasonable psychological adjustment and disease perception can promote the recovery of mental health. AIM: To explore the relationships among resilience, coping style, and uncertainty in illness of stroke patients. METHODS: A retrospective study was used to investigate 154 stroke patients who were diagnosed and treated at eight medical institutes in Henan province, China from October to December 2019. We used the Mishel Uncertainty in Illness Scale, the Connor-Davidson Resilience Scale, and the Medical Coping Modes Questionnaire to test the uncertainty in illness, resilience, and coping style, respectively. RESULTS: Resilience had a significant moderating role in the correlation between coping style and unpredictability and information deficiency for uncertainty in illness (P < 0.05). Further, the tenacity and strength dimensions of resilience mediated the correlation between the confrontation coping style and complexity, respectively (P < 0.05). The strength dimension of resilience mediated the correlation between an avoidance coping style and the unpredictability of uncertainty in illness (P < 0.05), as well as correlated with resignation, complexity, and unpredictability (P < 0.05). CONCLUSION: Resilience has moderating and mediating roles in the associations between coping style and uncertainty in illness, indicating that it is vital to improve resilience and consider positive coping styles for stroke patients in the prevention and control of uncertainty in illness.

2.
Front Oncol ; 11: 705866, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660273

RESUMO

Introduction: The aim of this study is to rigorously review the efficacy and safety of olanzapine in chemotherapy-induced nausea and vomiting (CINV) settings including (1) at 5- and 10-mg doses, and (2) the setting of highly emetogenic chemotherapy (HEC) and moderately emetogenic chemotherapy (MEC). Methods: Embase, Pubmed, and Cochrane Library were searched from the establishment of the database through April 18, 2021. The primary efficacy endpoints were the rate of complete response (CR; no emesis and no rescue), in the acute (0-24 h post-chemotherapy), delayed (24-120 h post-chemotherapy), and overall (0-120 h post-chemotherapy) phases. The secondary efficacy endpoints were the rates of complete control (CC, no nausea, and no emesis), for each phase. Safety endpoints were the rate of somnolence, as assessed by Common Terminology Criteria for Adverse Events (CTCAE) criteria. The Mantel-Haenszel, random, or fixed-effect analysis model was used to compute risk ratios and accompanying 95% confidence intervals for each endpoint. For endpoints that statistically favored one arm, absolute risk differences were computed to assess whether there is a 10% or greater difference, used as the threshold for clinical significance by MASCC/ESMO. Result: Nine studies reported the use of 10 mg olanzapine to prevent CINV; three studies reported the use of 5 mg olanzapine to prevent CINV. When olanzapine was administered at 10 mg for HEC patients, the six endpoints were statistically and clinically better than the control group. For MEC patients, four out of six endpoints were better than the control group. When olanzapine is administered at 5 mg for MEC patients, four endpoints have statistical and clinical advantages. The sedative effects of 10 and 5 mg olanzapine were statistically more significant than those of the control group. The sedative effect of the 10-mg olanzapine group was more significant than that of the 5-mg olanzapine group, both statistically and clinically. Conclusion: 5 mg olanzapine may be as effective as 10 mg olanzapine for patients with HEC and MEC, and its sedative effect is lower than 10 mg olanzapine. Fewer studies on 5 mg olanzapine have led to uncertain data. In the future, more randomized controlled trials of 5 mg olanzapine are needed to study the balance between the effectiveness and safety of olanzapine.

3.
Opt Express ; 29(8): 11773-11783, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984952

RESUMO

We propose a scheme to generate squeezed states of magnon and phonon modes and verify squeezing transfer between different modes of distinct frequencies in a cavity magnomechanical system which is composed of a microwave cavity and a yttrium iron garnet sphere. We present that by activating the magnetostrictive force in the ferrimagnet, realized by driving the magnon mode with red-detuned and blue-detuned microwave fields, the driven magnon mode can be prepared in a squeezed state. Moreover, the squeezing can be transferred to the cavity mode via the cavity-magnon beamsplitter interaction with strong magnomechanical coupling. We show that under the weak coupling regime, large mechanical squeezing of phonon mode can be achieved, which verifies that our scheme can find the existence of quantum effects at macroscopic scales. Furthermore, distinct parameter regimes for obtaining large squeezing of the magnons and phonons are given, which is the principal feature of our scheme. The considered scheme can be extended to hybrid optical systems, and can facilitate the advancement for realization of strong mechanical squeezing in cavity magnomechanical systems.

4.
IEEE Trans Cybern ; 51(2): 927-937, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31094698

RESUMO

In this paper, the output synchronization problem for complex dynamical networks (CDNs) with multiple output or output derivative couplings is discussed in detail. Under the help of Lyapunov functional and inequality techniques, an output synchronization criterion is presented for CDNs with multiple output couplings (CDNMOCs). To ensure the output synchronization of CDNMOCs, an adaptive control scheme is also devised. Similarly, we also take into account the adaptive output synchronization and output synchronization of CDNs with multiple output derivative couplings. At last, several numerical examples are designed to testify the effectiveness of the proposed results.

5.
IEEE Trans Cybern ; 51(7): 3845-3857, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31634149

RESUMO

In this article, two kinds of complex dynamical networks (CDNs) with state and derivative coupling are investigated, respectively. First, some important concepts about finite-time passivity (FTP), finite-time output strict passivity, and finite-time input strict passivity are introduced. By making use of state-feedback controllers and adaptive state-feedback controllers, several sufficient conditions are given to guarantee the FTP of these two network models. On the other hand, based on the obtained FTP results, some finite-time synchronization criteria for the CDNs with state and derivative coupling are gained. Finally, two simulation examples are proposed to verify the availability of the derived results.

6.
Opt Express ; 28(20): 28942-28953, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114802

RESUMO

The dissipative squeezing mechanism is an effective method to generate the strong squeezing, which is important in the precision metrology. Here, we propose a practical method to achieve arbitrary bosonic squeezing via introducing frequency modulation into the coupled harmonic resonator model. We analyze the effect of frequency modulation and give the analytical and numerical squeezing results, respectively. To measure the accurate dynamic squeezing in our proposal, we give a more general defination of the relative squeezing degree. Finally, the proposed method is extended to generate the strong mechanical squeezing (>3 dB) in a practical optomechanical system consisting of a graphene mechanical oscillator coupled to a superconducting microwave cavity. The result indicates that the strong mechanical squeezing can be effectively achieved even when the mechanical oscillator is not initially in its ground state. The proposed method expands the study on nonclassical state and does not need the bichromatic microwave driving technology.

7.
Opt Lett ; 45(9): 2604-2607, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32356827

RESUMO

We propose a scheme to enhance the single- and two-photon blockade effects significantly in a nonlinear hybrid optomechanical system with optical parametric amplification (OPA). The scheme does not rely on strong single-photon optomechanical coupling and can eliminate the disadvantages of suppressing multi-photon excitation incompletely. Through analyzing the single-photon blockade (1PB) mechanism and optimizing the system parameters, we obtain a perfect 1PB with a high occupancy probability of single-photon excitation, which means that a high-quality and efficient single-photon source can be generated. Moreover, we find that not only the two-photon blockade (2PB) effect is significantly enhanced, but also the region where 2PB occurs is widened when OPA exists, where we also derive the optimal parameter condition to maximize two-photon emission and higher photon excitations intensely suppressed at the same time.

8.
Polymers (Basel) ; 12(2)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054073

RESUMO

Semi-alicyclic colorless and transparent polyimide (CPI) films usually suffer from the high linear coefficients of thermal expansion (CTEs) due to the intrinsic thermo-sensitive alicyclic segments in the polymers. A series of semi-alicyclic CPI films containing rigid-rod amide moieties were successfully prepared in the current work in order to reduce the CTEs of the CPI films while maintaining their original optical transparency and solution-processability. For this purpose, two alicyclic dianhydrides, hydrogenated pyromellitic anhydride (HPMDA, I), and hydrogenated 3,3',4,4'-biphenyltetracarboxylic dianhydride (HBPDA, II) were polymerized with two amide-bridged aromatic diamines, 2-methyl-4,4'-diaminobenzanilide (MeDABA, a) and 2-chloro-4,4'-diaminobenzanilide (ClDABA, b) respectively to afford four CPI resins. The derived CPI resins were all soluble in polar aprotic solvents, including N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc). Flexible and tough CPI films were successfully prepared by casing the PI solutions onto glass substrates followed by thermally cured at elevated temperatures from 80 °C to 250 °C. The MeDABA derived PI-Ia (HPMDA-MeDABA) and PI-IIa (HBPDA-MeDABA) exhibited superior optical transparency compared to those derived from ClDABA (PI-Ib and PI-IIb). PI-Ia and PI-IIa showed the optical transmittances of 82.3% and 85.8% at the wavelength of 400 nm with a thickness around 25 µm, respectively. Introduction of rigid-rod amide moiety endowed the HPMDA-PI films good thermal stability at elevated temperatures with the CTE values of 33.4 × 10-6/K for PI-Ia and 27.7 × 10-6/K for PI-Ib in the temperature range of 50-250 °C. Comparatively, the HBPDA-PI films exhibited much higher CTE values. In addition, the HPMDA-PI films exhibited good thermal stability with the 5% weight loss temperatures (T5%) higher than 430 °C and glass transition temperatures (Tg) in the range of 349-351 °C.

9.
Opt Express ; 27(21): 29581-29593, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684217

RESUMO

We present a proposal to generate robust optomechanical entanglement induced by the blue-detuning laser and the mechanical gain in a double-cavity optomechanical system. We show that the stability of the system can be obtained by introducing a cavity mode driven by the red-detuning laser in the blue-detuning regime. In contrast to the red-detuning regime, we find that the entanglement in the blue-detuning regime is extremely robust to temperature. The cavity mode driven by the blue-detuning laser can control indirectly the optomechanical entanglement between mechanical resonator and cavity mode driven by the red-detuning laser. Moreover, the entanglement between two cavity modes without direct coupling can also be achieved in our system. Although the entanglement is weak, it is robust to temperature, and meanwhile, the optomechanical entanglement is hardly affected by the temperature when the damping rate of the mechanical oscillator is close to zero. Furthermore, the entanglement amplification at high temperature can be achieved by adjusting the mechanical gain appropriately. Our proposal provides an efficient way to achieve robust optomechanical entanglement in the blue-detuning regime and entanglement amplification in optomechanical system with mechanical gain.

10.
Opt Express ; 27(16): 22855-22867, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510570

RESUMO

We present a scheme for the electromagnetically induced transparency (EIT)-like nonlinear ground-state cooling in a double-cavity optomechanical system in which an optical cavity mode is coupled parametrically to the square of the position of a mechanical oscillator, an additional auxiliary cavity is coupled to the optomechanical cavity. The optimum cooling conditions is derived, based on which the heating process can be well suppressed and the mechanical resonator can be cooled with an optimal effect to near its ground state through EIT-like cooling mechanism even in unresolved sideband regime. It is demonstrated by numerical simulations that not only the average phonon number of steady state is lower than that of single-cavity optomechanical system, but also the cooling rate is greatly faster than that of the linear optomechanical coupling due to the two-phonon cooling process in the quadratic coupling. Also, the ground-state cooling is achievable even with a relatively weak quadratic coupling strengthby tunning the coupling between two cavities to reach the optimum cooling conditions, thus provides an solution for overcoming the limitations of weak quadratic coupling rate in experiments. The proposed approach provides a platform for quantum manipulation of macroscopic mechanical devices beyond the resolved sideband limit and linear coupling regime.

11.
Opt Express ; 26(13): 16250-16264, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119459

RESUMO

Experimental realization of the Kitaev model is a greatly attractive topic due to the potential applications to build robust qubits against decoherence in topological quantum computation. In this work, we investigate the charged whispering-gallery microcavity array model and simulate the normal Kitaev chain under this mechanism in the first time. We find that the system reveals profound connections with the normal Kitaev chain and its some derivatives, and the topological property of the system depends on effective optomechanical coupling strength deeply. In optomechanically induced Kitaev topologically nontrivial phase, compared to the normal Kitaev chain in the Majorana basis, the novel and distinct structure of charged whispering-gallery microcavity array model leads to controllable photonic and phononic edge localization. Furthermore, we also simulate the extended Kitaev chain and show that two topologically different nontrivial phases of the system allow one to realize more freewheeling controllable photonic and phononic edge localization. Our model offers an alternative approach to correlate with other more complicated one-dimensional noninteracting spinless topological systems relevant to the p-wave superconducting pairing.

12.
Opt Express ; 26(5): 6143-6157, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29529808

RESUMO

A scheme is proposed to cool a rotating mirror close to its ground state in a double-Laguerre-Gaussian-cavity optomechanical system, where an auxiliary cavity and a two-level atomic ensemble simultaneously couple to the original optomechanical cavity. By choosing parameters reasonably, we find that the cooling process of the rotating mirror can be strengthened greatly while the heating process can be suppressed effectively. We show that the proposed ground-state cooling scheme can work well no matter whether in the weak or strong coupling regime for the atomic ensemble and original cavity. Compared with previous related schemes, our scheme works in the unresolved sideband regime with fewer strict limitations for the auxiliary systems.

13.
Sci Rep ; 7(1): 2545, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28566715

RESUMO

We propose a scheme to show that the system consisting of two macroscopic oscillators separated in space which are coupled through Coulomb interaction displays the classical-to-quantum transition behavior under the action of optomechanical coupling interaction. Once the optomechanical coupling interaction disappears, the entanglement between the two separated oscillators disappears accordingly and the system will return to classical world even though there exists sufficiently strong Coulomb coupling between the oscillators. In addition, resorting to the squeezing of the cavity field generated by an optical parametric amplifier inside the cavity, we discuss the effect of squeezed light driving on this classical-to-quantum transition behavior instead of injecting the squeezed field directly. The results of numerical simulation show that the present scheme is feasible and practical and has stronger robustness against the environment temperature compared with previous schemes in current experimentally feasible regimes. The scheme might possibly help us to further clarify and grasp the classical-quantum boundary.

14.
Sci Rep ; 6: 38559, 2016 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-27917939

RESUMO

We study the physical properties of double-cavity optomechanical system in which the mechanical resonator interacts with one of the coupled cavities and another cavity is used as an auxiliary cavity. The model can be expected to achieve the strong optomechanical coupling strength and overcome the optomechanical cavity decay, simultaneously. Through the coherent auxiliary cavity interferences, the steady-state squeezing of mechanical resonator can be generated in highly unresolved sideband regime. The validity of the scheme is assessed by numerical simulation and theoretical analysis of the steady-state variance of the mechanical displacement quadrature. The scheme provides a platform for the mechanical squeezing beyond the resolved sideband limit and solves the restricted experimental bounds at present.

15.
Sci Rep ; 6: 33404, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27624534

RESUMO

We propose a scheme for the creation of robust entanglement between a movable mirror and atomic ensemble at the macroscopic level in coupled optomechanical system. We numerically simulate the degree of entanglement of the bipartite macroscopic entanglement and show that it depends on the coupling strength between the cavities and is robust with respect to the certain environment temperature. Inspiringly and surprisingly, according to the reported relation between the mechanical damping rate and the mechanical frequency of the movable mirror, the numerical simulation result shows that such bipartite macroscopic entanglement persists for environment temperature up to 170 K, which breaks the liquid nitrogen cooling and liquid helium cooling and largely lowers down the experiment cost. We also investigate the entanglement transfer based on this coupled system. The scheme can be used for the realization of quantum memories for continuous variable quantum information processing and quantum-limited displacement measurements.

16.
Sci Rep ; 6: 30929, 2016 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-27499169

RESUMO

We propose an effective scheme of shortcuts to adiabaticity for generating a three-dimensional entanglement of two atoms trapped in a cavity using the transitionless quantum driving (TQD) approach. The key point of this approach is to construct an effective Hamiltonian that drives the dynamics of a system along instantaneous eigenstates of a reference Hamiltonian to reproduce the same final state as that of an adiabatic process within a much shorter time. In this paper, the shortcuts to adiabatic passage are constructed by introducing two auxiliary excited levels in each atom and applying extra cavity modes and classical fields to drive the relevant transitions. Thereby, the three-dimensional entanglement is obtained with a faster rate than that in the adiabatic passage. Moreover, the influences of atomic spontaneous emission and photon loss on the fidelity are discussed by numerical simulation. The results show that the speed of entanglement implementation is greatly improved by the use of adiabatic shortcuts and that this entanglement implementation is robust against decoherence. This will be beneficial to the preparation of high-dimensional entanglement in experiment and provides the necessary conditions for the application of high-dimensional entangled states in quantum information processing.

17.
Sci Rep ; 6: 24421, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27091072

RESUMO

Quantum squeezing of mechanical resonator is important for studying the macroscopic quantum effects and the precision metrology of weak forces. Here we give a theoretical study of a hybrid atom-optomechanical system in which the steady-state squeezing of the mechanical resonator can be generated via the mechanical nonlinearity and cavity cooling process. The validity of the scheme is assessed by simulating the steady-state variance of the mechanical displacement quadrature numerically. The scheme is robust against dissipation of the optical cavity, and the steady-state squeezing can be effectively generated in a highly dissipative cavity.

18.
Sci Rep ; 5: 11321, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26225781

RESUMO

Teleportation of unitary operations can be viewed as a quantum remote control. The remote realization of robust multiqubit logic gates among distant long-lived qubit registers is a key challenge for quantum computation and quantum information processing. Here we propose a simple and deterministic scheme for teleportation of a Toffoli gate among three spatially separated electron spin qubits in optical microcavities by using local linear optical operations, an auxiliary electron spin, two circularly-polarized entangled photon pairs, photon measurements, and classical communication. We assess the feasibility of the scheme and show that the scheme can be achieved with high average fidelity under the current technology. The scheme opens promising perspectives for constructing long-distance quantum communication and quantum computation networks with solid-state qubits.

19.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 27(2): 143-5, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21315041

RESUMO

AIM: To construct chimeric adenoviral vector Ad5/11 carrying reporter gene eGFP and human endostatin-K5. METHODS: Chimeric adenoviral backbone vector expressing eGFP was generated by overlap PCR and homologous recombination in E.coli BJ5183. Then chimeric adenoviral vector Ad5/11-E1-CMV-endo-K5/E3-CMV-eGFP carrying eGFP and human endostatin-K5 was constructed by co-transfecting Pac I linearized chimeric adenoviral backbone and adenoviral E1 shuttle vector expressing human endostatin-K5 into HEK 293 cells. The expression of eGFP was observed under fluorescent microscope. The expression of human endostain-K5 in U87MG cells infected by chimeric adenoviral vector was detected by RT-PCR. The infection efficiency between chimeric adenovirus and unmodified control adenovirus for human glioblastoma cell line A172 and breast cancer cell line MDA-MB-231 in vitro was evaluated by the comparison of the expression of eGFP. RESULTS: Chimeric adenovirus Ad5/11-E1-CMV-endo-K5/E3-CMV-eGFP could successfully express eGFP and endostatin-K5. Chimeric adenoviral vector significantly enhances the infection efficiency for human glioblastoma cell line A172 and breast cancer cell line MDA-MB-231 compared with unmodified adenoviral vector Ad5 E1-CMV-eGFP. CONCLUSION: Chimeric adenoviral vector Ad5/11-E1-CMV-endo-K5/E3-CMV-eGFP can significantly improve the infection efficiency for human glioblastoma cell line A172 and breast cancer cell line MDA-MB-231.


Assuntos
Adenoviridae/genética , Endostatinas/genética , Endostatinas/metabolismo , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica/genética , Técnicas de Transferência de Genes , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos
20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 41(2): 199-202, 217, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20506634

RESUMO

OBJECTIVE: To construct red fluorescent protein (DsRed) and mouse vascular endothelial growth factor (mVEGF) lentiviral expression vector in order to obtain the DsRed and VEGF expression in 293T cells. METHODS: The mVEGF was amplified from the lungs of fetal mouse by RT-PCR. The IRES-DsRed was obtained from plasmid pLV-tTRKRAB-red which contains IRES-DsRed sequence by PCR. Then they were cloned into lentiviral expression vector pTK-208. Human embryonic kidney 293T cells were co-transfected with the three plasmids by lipofectamine, and the expression of DsRed was examined under fluorescent microscope 24 h and 48 h after transfection. 48 h and 72 h later the viral supernatant was used to infect 293T cells, the expression of DsRed was examined under fluorescent microscope and Western blot assays was used to examine the expression of mVEGF in cells and the culture medium. RESULTS: The recombinant lentiviral vector pTK208-mVEGF-IRES-DsRed was constructed, the virus titres were above 10(6) PFU/mL in the supernatant. After infection, DsRed and mVEGF proteins were successfully expressed in 293T cells. CONCLUSION: The lentiviral vector pTK208-mVEGF-IRES-DsRed contains DsRed and mVEGF were successfully constructed and expressed in 293T cells, it could provide a basis for further researches on the pathophysiological mechanism of VEGF and lay the foundation of gene therapy.


Assuntos
Vetores Genéticos/genética , Lentivirus/genética , Transfecção , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Embrião de Mamíferos , Células HEK293 , Humanos , Lentivirus/metabolismo , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Camundongos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Fator A de Crescimento do Endotélio Vascular/genética
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