Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title> <jats:p>Copper ions can promote amyloid diseases that are associated with amyloid peptides, such as type 2 diabetes (T2D), Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS). However, the underlying molecular mechanism remains obscure. Here we present that Cu<jats:sup>2+</jats:sup> is able to specifically bind to the backbone of T2D-related human islet amyloid polypeptide (hIAPP) by forming a ring structure, which causes the reduction of Cu<jats:sup>2+</jats:sup> to Cu<jats:sup>+</jats:sup> to produce reactive oxygen species (ROS) and the modulation of hIAPP aggregation. Nuclear magnetic resonance spectroscopy showed that Cu<jats:sup>2+</jats:sup> bound to the backbone of a turn region, His18-Ser21, which is critical for hIAPP aggregation. <jats:italic>Ab initio</jats:italic> calculations and X-ray absorption fine structure analyses revealed that Cu<jats:sup>2+</jats:sup> simultaneously bound with both the amide nitrogen and carbonyl oxygen on the peptide backbone, resulting in a ring structure, and causing the reduction of Cu<jats:sup>2+</jats:sup> to Cu<jats:sup>+</jats:sup> to form a hIAPP-Cu<jats:sup>+</jats:sup> complex. 2’,7’-Dichlorodihydrofluorescin diacetate fluorescence measurements further indicated that this complex led to enhanced ROS levels in rat insulinoma cells. Additionally, thioflavin T fluorescence and atomic force microscopy measurements denoted that the backbone-Cu ring structure largely modulated hIAPP aggregation, including the inhibition of hIAPP fibrillation and the promotion of peptide oligomerization. These findings shed new light on the molecular mechanism of Cu<jats:sup>2+</jats:sup>-induced amyloid toxicity involving both the enhancement of ROS and the modulation of hIAPP aggregation.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In II. OPTICAL THEORY OF FILM, Eq.(6) should be&lt;br/&gt;L=D$\sqrt {1 - \frac{{(1 - {n^2})}}{{s{in^2}{\theta _m}}}} $&lt;br/&gt;All subsequent derivations are given based on the correct Eq.(6), so the conclusions in the paper are not affected by the errata.”</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Influence of acceleration of electron on relativistic nonlinear Thomson scattering in tightly focused linearly polarized laser pulses is investigated for the first time. In the framework of classical electrodynamics, it is deduced and found that the more severe the change of the electron transverse acceleration, the stronger the asymmetry of the radiation angle distribution and the greater the transverse acceleration, the greater the radiation energy. Tightly focused, ultrashort, and high-intensity lasers lead to violent electron acceleration processes, resulting in a bifurcated radiation structure with asymmetry and higher energy. Additionally, the change of the initial phase of the laser brings about the periodic change of the acceleration, which in turn makes the radiation change periodically with the initial phase. In other cases, the radiation is in a symmetrical double-peak structure. These phenomena will help us to modulate radiation with more energy collimation.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>All-inorganic, hole-transporting-layer-free CsPbIBr<jats:sub>2</jats:sub> perovskite solar cells have great development potential, but their device performance needs to be further improved. Recently, metal nanostructures have been successfully applied in the field of solar cells to improve their performance. Nano Ag-enhanced power conversion efficiency in one CsPbIBr<jats:sub>2</jats:sub> perovskite solar cell utilizing the localized surface plasmon of Ag nanoparticles on the surface has been researched experimentally and simulatively in this paper. The Localized Surface Plasmon Resonance of Ag NPs has a near-field enhancement effect, which is expected to improve the light absorption of CsPbIBr<jats:sub>2</jats:sub> perovskite photovoltaic devices. In addition, Ag nanoparticles possess the forward scattering effect to the incident light, which can also improve the performance of CsPbIBr<jats:sub>2</jats:sub>-based perovskite photovoltaic devices. Directly assembling Ag nanoparticles (with a size of about 150 nm) on the surface of FTO, it is found when the particle surface coverage is 10%, the CsPbIBr<jats:sub>2</jats:sub> perovskite photovoltaic device achieves the champion PCE of 2. 7%, which is 9. 76% higher than that of the control group. Without changing any existing structure of the ready-made solar cell, this facile and efficient method has huger applications. To our best knowledge, this paper is the first report on nano Ag-enhanced photoelectric conversion efficiency in this kind of CsPbIBr<jats:sub>2</jats:sub> perovskite solar cell.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The growing worldwide energy needs call for developing novel materials for energy applications. <jats:italic>Ab initio</jats:italic> density functional theory (DFT) calculations allow the understanding and prediction of material properties at the atomic scale, thus, play an important role on the energy materials design. Due to the fast progress of computer power and development of calculation methodologies, DFT-based calculations have greatly improved its predictive power, and are now leading to a paradigm shift towards theory-driven materials design. The aim of this perspective is to introduce the advances in DFT calculations which accelerate energy materials design. We first present state-of-the-art DFT methods for accurate simulation of various key properties of energy materials. Then we show examples of how these advances lead to the discovery of new energy materials for photovoltaic, photocatalytic, thermoelectric, and battery applications. The challenges and future research directions in computational design of energy materials are highlighted at the end.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In this paper, by employing the complexification method and velocity resonant principle to $N$-solitons of the (2+1)-dimensional generalized KDKK equation, we obtain the soliton molecules, $T$-breather molecules, $T$-breather-$L$-soliton molecules and some interaction solutions when $N\leq6$. Dynamical behaviors of these solutions are discussed analytically and graphically. The method adopted can be effectively used to construct soliton molecules and $T$-breather molecules of other nonlinear evolution equations. The results obtained may be helpful for experts to study the related phenomena in oceanography and atmospheric science.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>High-dimensional quantum systems, such as qutrits (quantum three-level systems), have multiple accessible energy levels beyond the two-level qubits. Therefore, qutrits could offer a larger state space to improve the efficiency of quantum computation. Here, we demonstrate a high-fidelity iSWAP-like gate operation on a frequency-tunable superconducting qutrits system. The superconducting quantum system consists of two qutrits that are coupled via a resonator with fixed qutrit-resonator coupling strengths. Through designing the frequency pulse profile and optimizing the parameter values, the gate error could be suppressed below 1.5 ×10<jats:sup>-3</jats:sup>. To bear out the feasibility of the proposal, we have conducted our study with experimentally accessible parameters. As the resonator could mediate the interaction between the irrelevant qutrits, the presented approach could also be used to couple multiple qutrits together, providing a good platform for quantum information processing.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>An ocean-acoustic joint model is developed for the study of acoustic propagation uncertainty in internal wave environments. The internal waves are numerically produced by tidal forcing over a continental slope using an ocean model. Three parameters (i.e., internal wave, source depth, and water depth) contribute to the dynamic waveguide environments, and result in stochastic sound fields. The sensitivity of the transmission loss (TL) to environment parameters, statistical characteristics of the TL variation, and the associated physical mechanisms are investigated by the Sobol sensitivity analysis method, the Monte Carlo sampling, and the coupled normal mode theory, respectively. The results show that the TL is most sensitive to the source depth in the near field, resulted from the initial amplitudes of higher-order modes; while in the middle and the far fields, the internal waves are responsible for more than 80% of the total acoustic propagation contribution. In addition, the standard deviation of the TL in the near field and the shallow layer is smaller than in the middle and far fields and the deep layer.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>The structural, magnetic, and magnetocaloric effects (MCE) of Tm<jats:sub>1-<jats:italic>x</jats:italic> </jats:sub>Er<jats:sub> <jats:italic>x</jats:italic> </jats:sub>CuAl (<jats:italic>x</jats:italic> = 0.25, 0.5, and 0.75) compounds were investigated. The compounds undergo a second-order phase transition originating from the ferromagnetic to paramagnetic transition around 3.2 K, 5 K and 6 K, respectively. The maximum magnetic entropy change (-Δ<jats:italic>S</jats:italic> <jats:sub> <jats:italic>M</jats:italic> </jats:sub> <jats:sup> <jats:italic>max</jats:italic> </jats:sup> of Tm<jats:sub>1-<jats:italic>x</jats:italic> </jats:sub>Er<jats:sub> <jats:italic>x</jats:italic> </jats:sub>CuAl (<jats:italic>x</jats:italic> = 0.25, 0.5, and 0.75) are 17.1 J kg<jats:sup>-1</jats:sup>K<jats:sup>-1</jats:sup>, 18.1 J kg<jats:sup>-1</jats:sup>K<jats:sup>-1</jats:sup>, and 17.5 J kg<jats:sup>-1</jats:sup>K<jats:sup>-1</jats:sup> under the magnetic field change of 0-2 T, with corresponding <jats:italic>RC</jats:italic> of 131 J kg<jats:sup>-1</jats:sup>, 136 J kg<jats:sup>-1</jats:sup> and 126 J kg<jats:sup>-1</jats:sup>, respectively. The increase of -Δ<jats:italic>S</jats:italic> <jats:sub> <jats:italic>M</jats:italic> </jats:sub> <jats:sup> <jats:italic>max</jats:italic> </jats:sup> for Tm<jats:sub>0.5</jats:sub>Er<jats:sub>0.5</jats:sub>CuAl may be relevant to the change of magnetic moment distribution of Er and stress coming from element substitution. This work has provided several compounds that enrich the family of giant MCE materials in the cryogenic region.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>Photoreflectance (PR) spectroscopy is a powerful and nondestructive experimental technique to explore interband transitions of semiconductors. In most PR systems, the photon energy of the pumping beam is usually chosen to be higher than the bandgap energy of the sample. To the best of our knowledge, the highest energy of pumping laser in reported PR systems is 5.08 eV(244 nm), not yet in the vacuum ultraviolet (VUV) region. In this work, we report the design and construction of PR system pumped by VUV laser of 7.0 eV(177.3nm). At the same time, dual-modulated technique is applied and a dual channel lock-in-amplifier is integrated in the system for efficient PR measurement. The system’s performance is verified by the PR spectroscopy measurement of well-studied semiconductors, which testifies its ability to probe critical-point energies of the electronic band in semiconductors from ultraviolet to near-infrared spectral region.</jats:p>