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Proton pump inhibitors (PPIs) are often prescribed in association with clopidogrel and aspirin to patients with myocardial infraction (MI), but their effects on heart is controversial. The purpose of this study was to investigate the effects and potential mechanism of omeprazole (OME) and esomeprazole (ESO) in myocardial ischemia reperfusion (I/R) injury. In the present study, mice were treated with OME, ESO or vehicle for 3 weeks and then subjected to myocardial I/R or sham surgery. At 1 day after surgery, echocardiography was performed to access cardiac injury. Hematoxylin and eosin (HE) staining was performed to evaluate cardiomyocyte morphology. The IL1β was evaluated by Immunohistochemistry (IHC). Elisa was used to detect cTnt content in serum. The expression of CD86, CD206, CHOP, ATF6, eIF2α and p eIF2α were determined by Western blot (WB). The result showed that ESO markedly improved the left ventricular ejection fraction (LVEF), shortening fraction (FS), suppressed inflammatory infiltration, endoplasmic reticulum stress (ERS) and decreased proinflammatory macrophages in I/R hearts, while OME had no significant effects on cardiac function, inflammation and ERS in the I/R heart. In conclusion, ESO but not OME pretreatment reduces the proportion of proinflammatory macrophages, inhibits endoplasmic reticulum stress, and alleviates I/R injury in mice, indicating that ESO maybe a more proper PPI than OME for application in I/R injury.

Silver electrodes are commonly used as a conductive layer for electromagnetic devices. It has the advantages of good conductivity, easy processing, and good bonding with a ceramic matrix. However, the low melting point (961 °C) results in a decrease in electrical conductivity and migration of silver ions under an electric field when it works at high temperatures. Using a dense coating layer on the silver surface is a feasible way to effectively prevent the performance fluctuation or failure of the electrodes without sacrificing its wave-transmitting performance. Calcium-magnesium-silicon glass-ceramic (CaMgSi2O6) is a diopside material that has been widely used in electronic packaging materials. However, CaMgSi2O6 glass-ceramics (CMS) are facing tough challenges, such as high sintering temperature and insufficient density after sintering, which significantly confine its applications. In this study, CaO, MgO, B2O3, and SiO2 were used as raw materials to manufacture a uniform glass coating on the silver and Al2O3 ceramics surface via 3D printing technology followed by high-temperature sintering. The dielectric and thermal properties of the glass/ceramic layer prepared with various CaO-MgO-B2O3-SiO2 components were studied, and the protective effect of the glass-ceramic coating on the silver substrate at high temperatures were evaluated. It was found that the viscosity of the paste and the surface density of the coating increase with the increase of solid contents. The 3D-printed coating shows well-bonded interfaces between the Ag layer, the CMS coating, and the Al2O3 substrate. The diffusion depth was 2.5 μm, and no obvious pores and cracks can be detected. According to the high density and well-bonded glass coating, the silver was well protected from the corrosion environment. Increasing the sintering temperature and extending the sintering time is beneficial to form the crystallinity and the densification effect. This study provides an effective method to manufacture a corrosive-resistant coating on an electrically conductive substrate with outstanding dielectric performances.

Video platform is not only a social tool, but also an educational tool.The survey found that Vietnamese Chinese learners widely use YouTube to learn Chinese. However, there is not much research on it. Under the guidance of constructivism, language acquisition theory and immersion theory, this study aims to explore the effectiveness of using YouTube for Chinese teaching. Through the comprehensive methods of questionnaire survey and teaching experiment, the study found that the use of YouTube teaching has a positive impact on Chinese learning. They generally believe that YouTube creates a more real language environment, which is conducive to Chinese learning.

Heart failure is a condition caused by a variety of pathophysiological factors. One important pathological change of chronic heart failure is myocardial hypertrophy. In recent years, several studies have found that dysregulated microRNAs are involved in regulating the pathological process of heart failure. In this study, cardiac hypertrophy models were constructed using isoproterenol (ISO)-/angiotensin-II (Ang-II) to explore the role of miR-384-5p in cardiac hypertrophy and its molecular mechanism in vivo and in vitro. Echocardiography, invasive pressure-volume analysis and hematoxylin-eosin staining were used to explore cardiac structure and function. ALPK3 mRNA and protein expression were detected using quantitative reverse transcription polymerase chain reaction (RT-qPCR) and western blot analysis and miR-384-5p expression were assessed via RT-qPCR. Our findings determined that miR-384-5p was notably decreased in cardiac hypertrophic tissues and cells, and overexpression of miR-384-5p could ameliorate pressure overload. Furthermore, ALPK3 was determined to downregulate the ALPK3 expression to aggravate cardiomyocyte hypertrophy. Our findings provided a potential therapeutic target for the treatment of cardiac hypertrophy.

Hot/cold pressing is a very common process in powder metallurgy and polymer industry, in which powders are compacted at a temperature/pressure high enough to induce sintering and creeping processes, and make the materials much denser and stronger. In this study, we extent this strategy to the synthesis of carbon nanotube (CNT) nanocomposites, yet with the high compressive stress generated naturally during the ultra-filtration process. Employing dead filtration, which is traditionally employed to extract solids from solution in water treatment process, we fabricate CNTs/PVA nanocomposites with high CNTs loading. It was found that this process not only greatly accelerates the filtration, but also generates significant in-situ pressure on the nanocomposites during its formation. Such pressure can compress the nanocomposites in-situ from the very onset of the formation of the nanocomposites and at molecular scale, which makes the nanocomposites densely compacted and eventually translates to very high mechanical properties even at high CNTs concentrations of up to ∼90 vol%. The tensile strength and Young's modulus can be increased by 435% and 859%, respectively, and the toughness is comparable with the nacre at similar content of inorganic constituent.

The inverse Heusler compound Ti 2 CrSn with L 2 1 phase is predicted to be antiferromagnetic semiconductor with an indirect gap of 0.2 eV based on first principles and Boltzmann transport theory. The semiconducting character is stable within a large strain from −6% to 6%. The Cr, Ti 1 and Ti 2 moments all show a linear change behavior within the strain range of −6% ∼ 6%, however, the total zero moment is robust within that strain range. It should be a potential candidate for applying to magnetic tunnel junction device. The total zero moment originates from the fully occupied 9 orbitals for both up and down spin directions below the Fermi level. The spin dependent 3d hybridization feature is found that for up spin states the hybridization between Cr and Ti 2 is dominant while for down spin states the hybridization between Ti 1 and Ti 2 is dominant, however, there is no clear indication of hybridization between Cr and Ti 1 . The gap origin of the spin up (down) direction is that the 3d hybridization of Cr − Ti 2 ( Ti 1 − Ti 2 ) forms the bonding three degenerate t 2 g as well as two degenerate e g below the Fermi level, and also corresponding antibonding states of them above the Fermi level. This hybridization character also can be seen from the electron density difference that only the region between Cr and Ti 2 , and between Ti 1 and Ti 2 show clear electrons accumulation suggesting strong interaction. The calculated value of thermoelectric power factor is near to that of Bi 2 Te 3 , marking its potential application values in thermoelectric field.

Electroosmosis has been extensively employed as an effective method for the dewatering treatment of soils and thus the reinforcement of weak soils. At the microscopic level, this treatment process is inherently complex due to in situ chemical and electrochemical reactions, migration of ions and particles, and the dependence of zeta potential of various particles on the local pH value in the soil. This complexity has hindered further understanding of mechanisms underlying the electroosmosis technology. Here, we design an external electric field in which alternating pulse wave potentials were partially used to adjust the pH value of the soil and manipulate the dynamics of in situ formed nanoparticles and their interconnectivity. The experimental results reveal that the in situ formation of Ca-rich particles, instead of water drainage, may serve as the main mechanism underlying the observed soil reinforcement when using calcium chloride as the treatment electrolyte. The interconnectivity of such particles ma...

Controlling the water content in soil is crucial for the load bearing capacity of soil. In the past few decades, electroosmosis has been proved to be a versatile strategy to consolidate soil in situ. However, the efficiency of this electrochemical technique needs to be further improved for practical application. This study was designed to test the hypothesis that the incorporation of nanoparticles (NPs) during electroosmosis can significantly facilitate the migration of water molecules under an external electric field and thus improve the physical properties of the treated soil. In addition, the number of anodes per cathode was explored as another method to improve the efficiency of electroosmosis in dewatering and strengthening soil. The results from the designed laboratory experiments confirmed the benefits of increasing the number of anodes or adding positively charged SiO2@Al2O3 core–shell NPs, in increasing the dewatering rate and improving the cohesion, internal friction angle, and microstructure of the treated soil (Lake Silt). The finite element method based simulation results agreed well with the experimental observations and suggested that the NPs can promote the water migration under an electric field.

Graphene oxide (GO) is increasingly used in various applications, and the implications of this nano-sized material entering the natural environment are of great interest. GO is highly soluble in water, and its accumulation in soil could significantly alter the physical and mechanical properties of the soil. In this laboratory study, we mixed GO with a soil (clayey sand, SC) to systematically study the engineering properties and microstructure of the modified soil. The experimental results reveal that the physical and mechanical properties and microstructure of clayey sand can be significantly changed by the addition of a minute quantity of GO. The liquid limit and plasticity index of the soil steadily increased (up to a GO concentration of 0.08 wt%), whereas the plastic limit did not change significantly. The addition of GO (up to 0.08 wt%) into the soil generally decreased the soil's void ratio under a given hydrostatic consolidation pressure, while increasing its undrained shear strength. Such remarkable modifications of soil by minute amounts of GO can be attributed to the extremely high specific surface area of GO and its stable dispersion in water.

The electronic band structure and valley splitting of the WSe2/NiCl2 heterostructure have been investigated by density functional theory and Berry curvature calculations. We demonstrate that the valley polarization of monolayer WSe2 is induced due to the magnetic proximity effect caused by the single layer of ferromagnetic NiCl2. The magnitude of valley splitting depends on the stacking configurations of WSe2/NiCl2, and the maximum value of valley splitting reaches −11.87 meV. Large valley splitting can be achieved by adjusting the layer spacing and constructing a NiCl2/WSe2/NiCl2 heterojunction with Ni spins arranged in parallel between two NiCl2 sheets. The valley-contrasting Berry curvature between the K and K′ valleys suggests that the WSe2/NiCl2-based heterostructure could potentially be used as a valleytronic device to realize the valley-polarized anomalous Hall effect as both spin and valley filter.

To avoid the floods in urban pavement system, the use of permeable pavement is increasingly considered as an effective way to optimize the existing sealed pavement. Porous Asphalt (PA) has constituted the permeable pavement infrastructure for years, which can realize the fast infiltration and precipitation of surface water through layers. But the poor durability is the main obstacle inhibits the application of conventional PA. The substitution of the innovative Polyurethane binder can perform excellent mechanical property as well as the permeability. Apart from it, the filtration property is found effectively to reduce the quantity of particulate matter (PM) flooded by the rainfall. In this study, the filtration and clogging behavior of PU-bonded pavement under different concentration gradient of PM are quantified. Both filtration property and hydraulic conductivity are predicted by numerical modelling and adopted as comparative indexes. Results indicate that PU-Bonded permeable pavement has significant hydraulic conductivity and the effective absorptive-filtration performance for the contaminant of flow. The numerical modelling can well conduct the prediction of filtration and clogging performance of permeable pavement.

This paper focus on the issue of recognition of facial expressions in video sequences and propose a local-with-global method, which is based on local enhanced motion history image and CNN-RNN networks. On the one hand, traditional motion history image method is improved by using detected human facial landmarks as attention areas to boost local value in difference image calculation, so that the action of crucial facial unit can be captured effectively, then the generated LEMHI is fed into a CNN network for categorization. On the other hand, a CNN-LSTM model is used as an global feature extractor and classifier for video emotion recognition. Finally, a random search weighted summation strategy is selected as our late-fusion fashion to final predication. Experiments on AFEW, CK+ and MMI datasets using subject-independent validation scheme demonstrate that the integrated framework achieves a better performance than state-of-arts methods.

The thermodynamic, electronic and magnetic properties of Ni2MnX (X=Ge, Sn, Sb) Heusler alloys are investigated using the quasi-hormonic Debye model and the first principles calculation based on the density-functional-theory. The calculated results of the temperature dependent bulk modulus, coefficient of thermal expansion and the P–V relation for Ni2MnX (X=Ge, Sn, Sb) indicate that the bonding strength becomes stronger along the sequence of Ni2MnSb→Ni2MnSn→Ni2MnGe. The slower change trend of temperature dependent heat capacity of Ni2MnGe than that of Ni2MnSn and Ni2MnSb stems from the larger contribution of electronic heat capacity and smaller contribution of lattice heat capacity compared to the other two alloys. The ferromagnetic coupling order between the Ni and Mn is confirmed by our first principles calculations. The total moments in one primitive cell for the three alloys are all about 4.0 μB which are mainly carried by Mn atom with about 3.5 μB as can be seen from the magnetization density distribution.

In this work, a 3-D porous carbon nanotube sponge (CNTS) was embedded within a shape memory polymer (SMPs) matrix. We demonstrate complete infiltration and filling of the SMPs into the CNTS by capillary force without any damage to the CNTS structure. With only ~0.2 wt% carbon nanotube loading, the glass transition temperature is increased by ~20 °C, indicating strong interaction between CNTS and the SMPs matrix. Further, we find that the uniform distribution of the carbon nanotubes in the nanocomposite results in high electrical conductivity, and thus highly effective electricity triggering capability. The carbon nanotube sponge shape memory polymer (CNTS/SMPs) nanocomposite could be triggered within ~10 seconds by the application of ~10 volts. Results from finite element simulations showed good agreement with the experimental results, and indicated that for our system the interface thermal energy loss does not have a significant effect on the heating rate of the polymer matrix.

A microporous metal-organic framework (MOF), cobalt-based zeolitic imidazolate framework-67 (ZIF-67), was synthesized by the combination of solvent-free hand-mill and microwave irradiation, without any organic solvent and within 30 minutes. The hand-milling process can mix the reactants well by the virtue of high moisture/water absorption capacity of reactants. In addition, the outstanding electromagnetic wave absorption capability of cobalt leads to efficient conversion to MOF structures before carbonization. The obtained ZIF-67 possesses high surface area and micropore volume.

In a mine locomotive wireless network, multiple locomotives move along a tunnel and communicate with access points (APs) on the side of this tunnel. The underground working environment is not safe and thus it is important to maintain high quality communication links. We consider throughput maximization for a mine locomotive wireless network with successive interference cancellation (SIC) and power control. We define time segments such that within each segment, the set of locomotives that can communicate with an AP is fixed and the distance from each locomotive to this AP can be approximated as a constant. To maximize throughput for each segment, we first prove the existence of optimal solutions that satisfy certain features on SIC decoding order and SINR under SIC. Then we can formulate a linear programming problem to obtain optimal solutions. We further propose a concept of the maximum SIC set to reduce problem size and obtain a polynomial complexity algorithm. Simulation results show that our algorithm can increase throughput significantly by comparing with the algorithm using SIC only (no power control) and comparing with the algorithm without using SIC and power control.

In this paper, we analyze the effects of frequency offset to Weighted fractional Fourier transform (WFRFT) system under the time frequency fading channel. The expression of signal-to-interference ratio (SIR) due to ICI and ISI is derived for the first time. The bit error rate (BER) performance of BPSK modulation scheme of single-carrier (SC), OFDM and WFRFT-OFDM systems are simulated respectively. Simulation results show that when carrier offset exists, WFRFT system has superiority over both SC and OFDM systems by choosing an optimal fractional order.

Landau theory is used to describe the ferroelectric trigonal phase of Boracites. The temperature dependence of the principal reciprocal susceptibility is obtained. The calculated result shows that at the Curie temperature Tc, the spontaneous polarization jumps. The component of the principal reciprocal susceptibility perpendicular to polarization jumps but the component parallel to polarization does not. A possible experimental scheme for the measurement of the principal reciprocal susceptibility components is presented.

In this Letter a unified nonuniform cylindrical finite-difference–time-domain (NU-CFDTD) algorithm is utilized for the analysis and design of cylindrical millimeter-wave integrated circuits (CMICs). It is shown that the algorithm is efficient in coding and flexible in treating various materials and discontinuities without adding computational resources compared with the traditional FDTD method. A visual mesh generator, CylinMesh, is developed to generate nonuniform meshes and input parameter files for practical cylindrical MIC analysis and design. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 33: 256–262, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10291

The paper presents an efficient non-uniform, orthogonal mesh generation algorithm for the analysis and design of cylindrical microwave devices and integrated circuits using the cylindrical finite-difference time-domain (CFDTD) methods. By using this algorithm, we can easily generate a suitable CFDTD grid which is fitting for the developed CFDTD Maxwell's solver.

The traditional approach of implementing FDTD techniques is to develop different sets of update relations that accommodate for different computational regions, for example, normal FDTD and absorbing boundary condition (ABC) regions. In particular, when a perfectly matched layer (PML) is used for termination of computational grids, we have to deal with a number of field regions in terms of PML faces, edges, and corners which adds a tremendous work load and complexity to the programming environment. This paper aims to develop an efficient approach to analyze and design cylindrical MMICs. In it, we present a unified non-uniform cylindrical finite difference time domain (NU-CFDTD) algorithm in conjunction with an anisotropic perfectly matched layer (APML) ABC in a stretched-coordinate mapping system. The algorithm uses only one set of update equations to handle all computational regions, no matter if they are normal FDTD or PML regions. We determine a non-uniform grid pattern depending on the circuit density for a specific structure to save computational resources, while remaining satisfactory accuracy. In particular, the present algorithm can characterize different material regions by simply assigning different material parameters.

The Hg2CuTi-type structure is found to be preferable energy wise than the Cu2MnAl-type structure for full-Heusler Cr2MnAl and exhibits half-metallic ferromagnetism based on first principles. The calculations for the mixed compounds with disorder between B and D sublattices reveal that the case of exchanging one atom maintains the half-metallicity while the case of exchanging two atoms loses it. The electronic structures of the atoms at sites A or C are affected mainly by the nearest-neighboring coordination while that of the atoms at site B are determined by the next-nearest-neighboring coordination.