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61.
Myocardial infarction (MI) is the leading cause of premature death among adults. Cardiomyocyte death and dysfunction of the remaining viable cardiomyocytes are the main pathological factors of heart failure after MI. Mitochondrial complexes are emerging as critical mediators for the regulation of cardiomyocyte function. However, the precise roles of mitochondrial complex subunits in heart failure after MI remain unclear. Here, we show that NADH:ubiquinone oxidoreductase core subunit S1 (Ndufs1) expression is decreased in the hearts of heart failure patients and mice with myocardial infarction. Furthermore, we found that cardiac-specific Ndufs1 overexpression alleviates cardiac dysfunction and myocardial fibrosis in the healing phase of MI. Our results demonstrated that Ndufs1 overexpression alleviates MI/hypoxia-induced ROS production and ROS-related apoptosis. Moreover, upregulation of Ndufs1 expression improved the reduced activity of complex I and impaired mitochondrial respiratory function caused by MI/hypoxia. Given that mitochondrial function and cardiomyocyte apoptosis are closely related to heart failure after MI, the results of this study suggest that targeting Ndufs1 may be a potential therapeutic strategy to improve cardiac function in patients with heart failure.Subject terms: Heart failure, Myocardial infarction, Myocardial infarction  相似文献   
62.
Inspired by the chiral structure from mode interaction, a chiral terahertz metamaterial and its complementary structure with the coexistence of asymmetric transmission and circular dichroism response are designed. The asymmetric transmission happens in the presence of electric and magnetic modes perpendicular to each other, resulting from intrinsic chirality under normal incidence. Circular dichroism exists in the presence of electric and magnetic modes parallel to each other under oblique incidence because of extrinsic chirality. Both asymmetric transmission and circular dichroism are enhanced by complementary structures, benefitting from the coupling between adjacent units. The maximum of chiral parameter κ can achieve 450, which is one hundred times higher than previously reported. The chiral response can be tuned by the incident angle and is sensitive to the environmental refractive index. The results highlight the potential applications of these metamaterials in chiral sensing and polarization transformation devices.  相似文献   
63.
Optimal creation of photon Fock states is of importance for quantum information processing and state engineering.Here an efficient strategy is presented for speeding up generation of photon Fock state in a superconducting circuit via counterdiabatic driving.A transmon qubit is dispersively coupled to a quantized electrical field.We address a ∧-configuration interaction between the composite system and classical drivings.Based on two Gaussian-shaped drivings,a single-photon Fock state can be generated adiabatically.Instead of adding an auxiliary counterdiabatic driving,our concern is to modify these two Rabi drivings in the framework of shortcut to adiabaticity.Thus an accelerated operation with high efficiency can be realized in a much shorter time.Compared with the adiabatic counterpart,the shortcut-based operation is significantly insusceptible to decoherence effects.The scheme could offer a promising way to deterministically prepare photon Fock states with superconducting quantum circuits.  相似文献   
64.
In this paper we obtain the discrete integrable self-dual network hierarchy associated with a discrete spectral problem. On the basis of the theory of algebraic curves, the continuous flow and discrete flow related to the discrete self-dual network hierarchy are straightened using the Abel-Jacobi coordinates. The meromorphic function and the Baker-Akhiezer function are introduced on the hyperelliptic curve. Quasi-periodic solutions of the discrete self-dual network hierarchy are constructed with the help of the asymptotic properties and the algebra-geometric characters of the meromorphic function, the Baker-Akhiezer function and the hyperelliptic curve.  相似文献   
65.
La0.67Ca0.33MnO3 particle films with an average particle size of ~150 nm were grown on single-crystal silicon substrate using pulsed electron deposition technique and then focused ion beam was introduced to fabricate nanobridge in size of 300 × 900 nm on the particle film. The magneto-transport properties of both samples were studied. For the film, there is only one resistance peak at 182 K in temperature-dependent resistance (RT) curves, which is far lower than ferromagnetic–paramagnetic transition temperature (T C) of 250 K. When compared to the film, double peaks were observed in both RT curves and magnetoresistance dependent on temperature (MR–T) curves of the nanobridge, one peak is at 186 K, which is very close to metal–insulator transition temperature (T P) of film, the other one is at 250 K, which is close to the T C of film, and these two peaks caused separately by grain and grain boundary (GB), which demonstrated that the electrical transport behavior of grain was separated from that of GB.  相似文献   
66.
The electronic and superconducting properties of Fe_(1-δ)Se single-crystal flakes grown hydrothermally are studied by the transport measurements under zero and high magnetic fields up to 38.5 T. The results contrast sharply with those previously reported for nematically ordered Fe Se by chemical-vapor-transport(CVT) growth. No signature of the electronic nematicity, but an evident metal-to-nonmetal crossover with increasing temperature,is detected in the normal state of the present hydrothermal samples. Interestingly, a higher superconducting critical temperature T_c of 13.2 K is observed compared to a suppressed T_c of 9 K in the presence of the nematicity in the CVT Fe Se. Moreover, the upper critical field in the zero-temperature limit is found to be isotropic with respect to the field direction and to reach a higher value of ~42 T, which breaks the Pauli limit by a factor of 1.8.  相似文献   
67.
Lu YG  Zhang Y  Dong YW 《Ultrasonics》2006,44(Z1):e1419-e1422
Based on Jacobson's molecular free length theory in liquids and the relationship between ultrasonic velocity and the molecular free length in organic liquids, this paper deduces the equations for pressure coefficient and temperature coefficient of ultrasonic velocity and nonlinear acoustic parameter B/A in both of organic liquid and organic liquid binary mixtures. These nonlinear acoustic parameters are evaluated against the measured results and data from other sources. The equations reveal the connections between the nonlinear acoustic parameters and some internal structural of the medium or mixtures e.g. the sizes of molecule, several thermodynamic physical parameters and outside status e.g. condition of pressure and temperature of the liquid or liquid mixture. With the equations the nonlinear acoustic parameter B/A of organic liquid binary mixtures, which is impossible to know without the nonlinear acoustic parameter B/A of the tow components before, can be calculated based on the structural and physical parameters of organic liquid and organic liquid binary mixtures.  相似文献   
68.
MgO:Eu3+ nanocrystals with average diameter around 15 nm were prepared via a facile combustion method under a weak reductive atmosphere at temperature as low as 300°C. The photoluminescence spectra showed that the MgO:Eu3+ nanocrystals emit white light, the hypersensitive transition (5 D 07 F j of Eu3+) emission was prominent in the emission spectra resulting from the noinversion symmetry local site at which Eu3+ ions were located. Two kinds of luminescence sites of Eu3+ are identified by means of the fluorescence decay and site-selective spectroscopy. The excitation and absorption spectra indicated that the absorption of surface state decreased with the increase of Eu3+ concentration, meaning that the surface defect decreased through Eu3+ doping for some of them located at the disordered sites near the surface or absorbed at the surface of MgO host. Meanwhile, absorptivity and CIE chromaticity coordinates of all samples were measured; the results were in accordance with the excitation and absorption spectra and photoluminescence spectra, respectively.  相似文献   
69.
B2O3-P2O5-SiO2 (BPS) three-dimensional (3D) high-organized polystyrene (PS) opals and inverse opals with large domain were fabricated and characterized.  相似文献   
70.
We firstly give a nonlocal method for generating pair coherent state with two traveling wave fields in distinct districts. The experimental scheme proposed is based on a two-mode photon number matching process, which employs weak cross-Kerr media and on/off detection. Then we discuss the details for implementing this scheme, showing that it is robust against the low quantum efficiency of photon detectors and offers nearly perfect pair coherent states. Finally, we show how a two-mode Schrödinger cat state and a generalized two-mode correlated photon number state can be prepared via this matching process.  相似文献   
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